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Temporary wetlands: challenges and solutions to conserving a ‘disappearing’ ecosystem
... Vernal pools are small, temporary wetlands that are hydrologically isolated and fill up with water each spring to form pools that a variety of amphibians and invertebrates depend on for habitat and reproduction (Karraker and Gibbs 2009;Calhoun and deMaynadier 2008). The temporary nature of vernal pools keeps them free of fish and reduces the populations of other predators, providing feeding and resting places for amphibians and allowing them to breed with greater success (Calhoun et al. 2017;Rothenberger and Baranovic 2021;Hofmeister et al. 2022;Luymes and Chow-Fraser Samantha R. Kurkowski srkurkow@mtu.edu 1.6 kg P annually from vernal pools into the surrounding forests (Capps et al. 2015). ...
... Although vernal pools are vital to forests and wildlife, management and conservation of these features is lacking due to their temporary nature, small size, and the extent to which they are integrated into the forest matrix (Calhoun et al. 2003). The wide inter-annual variability in hydrologic conditions also makes it difficult to locate them, as pools may not always be inundated in spring, especially during dry years, and they are typically dry in the summer (Calhoun et al. 2017). These challenges will become increasingly difficult as climate change alters precipitation patterns and droughts become more frequent (Cartwright et al. 2022). ...
... Considering the forest surrounding vernal pools as well as the pools themselves is equally important in maintaining functional vernal pools, as amphibians and other vernal pool users spend most of their life in the upland leaf litter after mating, and canopy cover helps vernal pools persist longer into the summer by reducing evaporation rates (Richter et al. 2013;Gibbons 2003). Without proper protection, vernal pools are vulnerable to land use changes, climate change, forestry and agricultural operations, and urbanization (Preisser et al. 2000;Burne and Griffin 2005;Calhoun et al. 2017). ...
Vernal pools are small, ephemeral wetlands that become inundated each spring and provide many ecosystem services, including providing critical habitat to amphibians and invertebrates as their temporary nature keeps them free of fish. We collected data on vernal pool characteristics throughout five Great Lakes National Parks: Pictured Rocks National Lakeshore, Sleeping Bear Dunes National Lakeshore, Apostle Islands National Lakeshore, Isle Royale National Park, and Voyagers National Parks. Our goals were to characterize and assess how vernal pools vary within and across the five national parks, and determine which characteristics are most correlated with the presence of vernal pool indicator species. We sampled 139 pools during spring of 2021 and 2022 where we collected data on pool characteristics related to hydrology, soils, vegetation, geomorphology, and indicator species. We found that vernal pool substrate and forest type does vary between the different parks. Many vernal pool qualities are driven by the type of substrate they occur on and overstory canopy species and amount of tree cover. We also created a classification system that most highly correlated to indicator species presence and can be used in remote sensing products, resulting in a three-class system based on overstory species composition: Deciduous, Coniferous, and Open. Indicator species were more likely to occur in pools with either a deciduous or open canopy than pools with a coniferous canopy. This information can be used to inform land managers within the Great Lakes of vernal pool characteristics they can expect, and which pools are hotspots for indicator species.
... Temporary wetlands are intermittently inundated aquatic habitats that differ in the length and predictability of the hydroperiod (i.e., the duration, frequency, and timing of the aquatic phase; Calhoun et al. 2017). They are among the most endangered wetland types (Calhoun et al. 2017), especially in lowlands, because they have disappeared or deteriorated due to ecosystem conversion, mostly from intensive agriculture and river regulation (Brown 1998, Boix et al. 2016, Merta et al. 2016. ...
... Temporary wetlands are intermittently inundated aquatic habitats that differ in the length and predictability of the hydroperiod (i.e., the duration, frequency, and timing of the aquatic phase; Calhoun et al. 2017). They are among the most endangered wetland types (Calhoun et al. 2017), especially in lowlands, because they have disappeared or deteriorated due to ecosystem conversion, mostly from intensive agriculture and river regulation (Brown 1998, Boix et al. 2016, Merta et al. 2016. The composition of the aquatic invertebrate community in temporarily inundated habitats changes during the hydroperiod. ...
... Ephemeral wetlands are intermittently flooded (i.e., standing water is periodically present but without a seasonal pattern; van der Valk 2012), mainly influenced by weather (precipitation and evaporation), making their occurrence and the length of hydroperiods highly unpredictable. Moreover, they are patchily distributed (Schernhammer et al. 2020) and because of plowing are only visible in their aquatic phase within croplands, making their detection and maintenance difficult (Merta et al. 2016, Calhoun et al. 2017. ...
While it is well known that the temporal dynamics of aquatic invertebrate communities are influenced by the length of hydroperiods, only temporary wetlands with relatively long hydroperiods have been well studied. In contrast, few studies have focused on ephemeral wetlands, primarily represented by extremely ephemeral rock pools. In Central Europe, many ephemeral wetlands develop spontaneously directly on arable land, often on the sites of former natural wetlands that have been drained and converted to agricultural land. Here, we focused on aquatic invertebrates in ten ephemeral pools on arable land in southern Moravia, which were studied from inundation to desiccation. Despite relatively short hydroperiods of 5 to 11 weeks, we observed significant changes in community composition, including species replacement. Dynamics differed between macroinvertebrates and microcrustaceans and between different macroinvertebrate feeding and dispersal groups. Predation pressure increased over time and was highest during drying. Passive dispersers were most abundant during the middle phase, while the abundance of active dispersers increased throughout the hydroperiod. Because we did not detect a significant effect of any environmental factor on community change over time, we suppose, that the dynamic was driven by differences in species traits and biotic interactions rather than by the changing environment. This study fills a gap in our knowledge of the temporal dynamics of aquatic invertebrate communities in temporary wetlands by investigating wetlands with short, but not extremely ephemeral, hydroperiods.
... Globally temporary endorheic wetlands make up many surface waters in both arid and semi-arid regions such as Australia, Africa, Europe, and North America (Roshier et al., 2001;Calhoun et al., 2017;Mpakairi et al., 2022a). Endorheic depressions in wetlands referred to as pans in South Africa are also common in France (with vernal pools representing 0.05 % of the natural habitat), Europe and the USA. ...
... Temporary pans vary in size and hydroperiods (Williams, 2012). The hydroperiod is the main driver of these pan systems, often resulting in a unique biotic community characterised by a number of specialist plant and animal species only found within these t systems (Calhoun, 2017;Kochi et al., 2020;Brendonck et al., 2022). Anthropogenic effects such Mungenge et al. ...
... Freshwater systems are threatened globally by overexploitation, pollution, and destruction and/or degradation of habitat (Dudgeon et al., 2006;De Villiers, 2007;Reid et al., 2019). This is problematic as wetlands are often biodiversity hotspots that support high densities and diversities of wildlife (Calhoun, 2017). Nutrient enrichment (particularly phosphorous and nitrogen) associated with anthropogenic activities can therefore alter algal production within aquatic ecosystems and have detrimental consequences on these systems (Chislock et al., 2013). ...
Temporary pans are susceptible to various anthropogenic effects such as pollution, resource extraction, and land use intensification. However, given their small endorheic nature, they are almost entirely influenced by activities close to their internally drained catchments. Human–mediated nutrient enrichment within the pans can lead to eutrophication, resulting in increased primary productivity and decreased associated alpha diversity. The Khakhea–Bray Transboundary Aquifer region and the pan systems that characterise the area are understudied area with no records available of the biodiversity therein. Additionally, the pans are a major water source for the people in these areas. This study assessed differences in nutrients (i.e., ammonium, phosphates) and their effect on chlorophyll–a (chl–a) concentrations in pans along a disturbance gradient in the Khakhea–Bray Transboundary Aquifer region, South Africa. Physicochemical variables, nutrients, and chl–a were measured from 33 pans representing variable anthropogenic exposure during the cool–dry season in May 2022. Five environmental variables (i.e., temperature, pH, dissolved oxygen, ammonium, and phosphates) showed significant differences between the undisturbed and disturbed pans. The disturbed pans generally had elevated pH, ammonium, phosphates and dissolved oxygen compared to the undisturbed pans. A strong positive relationship was observed between chl–a and temperature, pH, dissolved oxygen, phosphates and ammonium. Chlorophyll–a concentration increased as surface area, and the distance from kraals, buildings and latrines decreased. Anthropogenic activities were found to have an overall effect on the pan water quality within the Khakhea–Bray Transboundary Aquifer region. Therefore, continuous monitoring strategies should be established to better understand the nutrient dynamics through time and the effect that this may have on productivity and diversity in these small endorheic systems.
... The smaller, temporarily ponded wetlands that were once much more common in the PPR landscape provide many important ecosystem services due to their unique properties [60]. For example, these smaller wetlands are the primary contributors to groundwater recharge to an aquifer [24,140] because they store and quickly lose water to groundwater. ...
... This is especially important under current climate conditions when many larger wetlands have remained at or near their spill point which limits their water-storage capacity. In addition to water storage, smaller wetlands are disproportionately important for their geochemical functions as well [60]. For example, smaller wetland basins have proportionally larger reactive zones, which make them more efficient in biogeochemical cycling [15]. ...
... However, in the future, climate warming will likely shift wetlands towards a dry state, which will disproportionately influence smaller wetlands. Currently, the smaller temporarily ponded wetlands continue to be the most vulnerable to future losses and are perhaps the most valuable for maintaining wetland landscape multifunctionality [13,15,24,60]. While it is hard to predict all of the potential climate and land-use scenarios and how they might alter prairie-pothole wetland ecosystems in the future, understanding the vulnerabilities of these systems to potential changes is an important consideration for proactive conservation planning strategies. ...
The homogenization of freshwater ecosystems and their biological communities has emerged as a prevalent and concerning phenomenon because of the loss of ecosystem multifunctionality. The millions of prairie-pothole wetlands scattered across the Prairie Pothole Region (hereafter PPR) provide critical ecosystem functions at local, regional, and continental scales. However, an estimated loss of 50% of historical wetlands and the widespread conversion of grasslands to cropland make the PPR a heavily modified landscape. Therefore, it is essential to understand the current and potential future stressors affecting prairie-pothole wetland ecosystems in order to conserve and restore their functions. Here, we describe a conceptual model that illustrates how (a) historical wetland losses, (b) anthropogenic landscape modifications, and (c) climate change interact and have altered the variability among remaining depressional wetland ecosystems (i.e., ecosystem homogenization) in the PPR. We reviewed the existing literature to provide examples of wetland ecosystem homogenization, provide implications for wetland management, and identify informational gaps that require further study. We found evidence for spatial, hydrological, chemical, and biological homogenization of prairie-pothole wetlands. Our findings indicate that the maintenance of wetland ecosystem multifunctionality is dependent on the preservation and restoration of heterogenous wetland complexes, especially the restoration of small wetland basins.
... Numerous unlisted but declining species and common species also depend on the global conservation of geographically isolated wetland habitats. However, like other small aquatic habitats, geographically isolated wetlands have few legal protections [8]. Historical and current wetland loss and degradation have made the restoration of geographically isolated wetlands a high priority for the conservation of pond-breeding amphibians [9,10]. ...
... Pond-breeding amphibians are resilient to these stochastic disturbances, provided that abundant wetlands are available across the landscape, in relative proximity to one another, and represent a range of hydroperiods [6,10,[20][21][22]. Historical and current destruction of wetlands disproportionately affects geographically isolated wetlands [3,8,[23][24][25]. Some land management and agricultural practices, including ditching and (or) draining, intensive site preparation, intensive livestock grazing, as well as fire exclusion, among others, have also contributed to past and current degradation of wetland conditions [3,8]. ...
... Historical and current destruction of wetlands disproportionately affects geographically isolated wetlands [3,8,[23][24][25]. Some land management and agricultural practices, including ditching and (or) draining, intensive site preparation, intensive livestock grazing, as well as fire exclusion, among others, have also contributed to past and current degradation of wetland conditions [3,8]. Given these pervasive threats and the historical destruction of many geographically isolated wetlands, restoring remaining habitat is essential for the conservation of pond-breeding amphibians [6,8,9]. ...
Geographically isolated wetlands provide a critical habitat for pond-breeding amphibians, a taxa of broad conservation concern. Global wetland loss and degradation has made restoration essential for amphibian conservation. Restoration goals typically include recovering the wetlands’ physiochemical, hydrological, and ecological functions. However, for pond-breeding amphibians, successful restoration should also result in sustained populations, which is difficult to assess and infrequently reported. In this paper, we review the available evidence that restoration of geographically isolated wetlands promotes pond-breeding amphibian occupancy and population persistence. We provide an overview of restoration practices addressing hydrology, vegetation, and ecological processes within these unique environments and across spatial scales. We then summarize the evidence, and discuss the limitations, for evaluating successful restoration within the context of amphibian conservation across these categories. Finally, we provide recommendations for researchers and practitioners to leverage prior successes and establish systematic data collection and dissemination. Moving restoration of wetlands for amphibian conservation forward will require more robust data collection and reporting.
... Although "NFW" has gradually gained acceptance in academia for emphasizing the geographical location rather than falsely generalizing the hydrological isolation of these waters (Mushet et al., 2015;Calhoun et al., 2017a;Lane et al., 2018), it is used inconsistently and often accompanied by "GIWs", even in the recent research literature and government documents (e.g., U.S. Environmental Protection Agency, 2015). Other terms including but not limited to "small water bodies" (Biggs et al., 2017), "neglected freshwater habitats" (Hunter et al., 2017), "temporary wetlands" (Calhoun et al., 2017b), "vulnerable waters" , and "wetlandscapes" (Thorslund et al., 2017;Ghajarnia et al., 2020) are used or partially used in studying similar small wetlands, but often with a specific focus on wetland attributes (e.g., size, perimeter-area-volume relationship, and hydroperiod), functions (e.g., flood attenuation, nutrient retention, and biodiversity support), and study scales (e.g., individual wetlands, wetlands across landscapes, and wetlands at watershed and regional scales), respectively. Such marked heterogeneity has been crossvalidated by several reviews and calls for improved research and collaborative utilization of these wetland systems (Hunter et al., 2017;Chen et al., 2019;Golden et al., 2019;Sayer et al., 2020), which indicate the prevailing perspectives at local and regional scales --NFWs are studied with different emphases under different motivations, depending upon where they are located and what we are interested in. ...
... We present here a vision for global collaboration, and outline four pathways that will enhance our understanding and sustainable use of these wetland systems across regions --from classification and simulation as theoretical and technical bases, to improved legislative/regulative support via mutual learning of governments, and bidirectionally reinforced education and science ( Figure 3). These recommendations, particularly for countries with similar geo-climatic settings and socioeconomic development levels (due to better opportunities to learn from each other), can complement existing frameworks of NFW utilization and protection for governments and agencies (Calhoun et al., 2017b;Golden et al., 2017;Hunter et al., 2017;Chen et al., 2019;Swartz and Miller, 2021), and have potential to galvanize broader international collaborations on sustainable wetland use. ...
... Schematic diagram of four activity areas to further the NFW typology framework and to promote collaboration and sustainable NFW use at global scales.Classification.NFWs have heterogeneous naming criteria in different geographical settings, e.g., relating to hydroperiod for temporary ponds(Calhoun et al., 2017b), landforms for karst ponds(Hill et al., 2018), structures for chainof-ponds (Williams et al., 2020), and purpose for farm ponds(Takeuchi et al., 2016) (Figure 1a). Previous studies have attempted semantic mediation among the terms used(Mushet et al., 2015; Leibowitz, 2015; ...
Non-floodplain wetlands (NFWs) are important but vulnerable inland freshwater systems that are receiving increased attention and protection worldwide. However, a lack of consistent terminology, incohesive research objectives, and inherent heterogeneity in existing knowledge hinder cross-regional information sharing and global collaboration. To address this challenge and facilitate future management decisions, we synthesized recent work to understand the state of NFW science and explore new opportunities for research and sustainable NFW use globally. Results from our synthesis show that although NFWs have been widely studied across all continents, regional biases exist in the literature. We hypothesize these biases in the literature stem from terminology rather than real geographical bias around existence and functionality. To confirm this observation, we explored a set of geographically representative NFW regions around the world and characteristics of research focal areas. We conclude that there is more that unites NFW research and management efforts than we might otherwise appreciate. Furthermore, opportunities for cross-regional information sharing and global collaboration exist, but a unified terminology will be needed, as will a focus on wetland functionality. Based on these findings, we discuss four pathways that aid in better collaboration, including improved cohesion in classification and terminology, and unified approaches to modeling and simulation. In turn, legislative objectives must be informed by science to drive conservation and management priorities. Finally, an educational pathway serves to integrate the measures and to promote new technologies that aid in our collective understanding of NFWs. Our resulting framework from NFW synthesis serves to encourage interdisciplinary collaboration and sustainable use and conservation of wetland systems globally.
... A spatially explicit inventory is essential to manage temporary wetlands on a landscape scale effectively [8,18]. Atmospheric conditions, the spatial resolution of the sensor being used [19], the cryptic nature of wetlands, and their short hydroperiods can limit the remote detection of small wetlands, as explained above. ...
... In conclusion, wetland inventories still need to be improved in many regions worldwide (e.g., China, South America, and Russia); additionally, small and ephemeral wetlands are often ignored or not identified in those areas where inventories have already been conducted [17,18]. Their small size, short hydroperiod, or severe disturbance-most of them has been transformed into farmland-make these ponds undetectable by most remote sensing systems. ...
Mediterranean temporary ponds are a priority habitat according to the Natura 2000 network of the European Union, and complete inventories of these ecosystems are therefore needed. Their small size, short hydroperiod, or severe disturbance make these ponds undetectable by most remote sensing systems. Here we show, for the first time, that the distributed hydrologic model IBER+ detects ephemeral and even extinct wetlands by fully exploiting the available digital elevation model and resolving many microtopographic features at drainage basin scales of about 1000 km2. This paper aims to implement a methodology for siting flood-prone areas that can potentially host a temporary wetland, validating the results with historical orthophotos and existing wetlands inventories. Our model succeeds in dryland endorheic catchments of the Upper Guadalquivir Basin: it has detected 89% of the previously catalogued wetlands and found four new unknown wetlands. In addition, we have found that 24% of the detected wetlands have disappeared because of global change. Subsequently, environmental managers could use the proposed methodology to locate wetlands quickly and cheaply. Finding wetlands would help monitor their conservation and restore them if needed.
... Research to date has generally focused on soil organic C (SOC) of permanently saturated wetlands, where anoxia and subsequently slow decomposition are strong environmental drivers of SOC storage. However, a considerable yet frequently overlooked subset of wetlands are seasonally saturated and therefore experience dry, oxic conditions annually (e.g., vernal pools, Delmarva bays, prairie potholes) (Zedler 2003;Brooks 2005;Calhoun et al. 2017). Under the existing understanding of wetland SOC storage, periodic drying of seasonally saturated wetlands might be expected to stimulate C emissions and SOC loss (Miao et al. 2017). ...
... The role of global wetlands as a future C sink or source is uncertain, as climate and land use change alter wetland area and biogeochemical processing (e.g., Dahl 2011;Kolka et al. 2018;Moomaw et al. 2018). While the wetlands in this study are relatively small in area, up to one-fifth of wetland area in this region experiences seasonally dynamic hydrology (MD iMAP 2016), and seasonally saturated wetlands are globally ubiquitous (Calhoun et al. 2017). Therefore, the seasonally saturated areas of many small wetlands are likely to have a large cumulative impact on SOC stocks at the landscape scale. ...
Wetlands store significant soil organic carbon (SOC) globally due to anoxic conditions that suppress SOC loss. However, stored SOC may become vulnerable to decomposition where climate and land use change alter wetland hydrology. Seasonally saturated wetlands experience fluctuating hydrologic conditions that could promote physicochemical mechanisms known to stabilize terrestrial SOC. These wetlands are therefore likely to be important for SOC storage at the landscape-scale. This study examined physicochemical stabilization of SOC within five seasonally saturated wetlands across a hydrologic gradient from the frequently saturated basin edge to the rarely saturated upland. At each wetland, we monitored water level and collected soil samples from the top two mineral horizons across five transect points to quantify physical protection of SOC in aggregates and organo-mineral associations between SOC and iron (Fe). As expected, both SOC concentrations and SOC stocks from 10–50 cm decreased across the transect from frequently saturated soils to rarely saturated soils. However, SOC stocks from 0–10 cm increased along this gradient, indicating diverging SOC dynamics throughout the soil profile. The majority of SOC was associated with macroaggregates across the transect, suggesting that macroaggregates are likely to physically protect wetland SOC during seasonal drying. By contrast, Fe-associated SOC was low across the transect, though modest accumulations of Fe (5 mg Fe g−1 soil) were observed in the transition zone where saturation was most dynamic throughout the year. Our results suggest that SOC stabilization occurs via physical protection within macroaggregates and, to a lesser extent, organo-mineral associations during dry periods in and around seasonally saturated wetlands. As climate scenarios predict intensified wet and dry cycles in many wetlands, understanding SOC stabilization is critical to predicting vulnerability to future change.
... Other issues, such as insufficient legislative policy, conflicts of interest, and insufficient funding, contributed significantly to the overall complexities of wetland management. According to Calhoun et al. (2017), one significant challenge was the lack of coordination and communication among different stakeholders involved in wetland management. Additionally, these multiple gaps are linked to the absence of a specific institution responsible for the management of these highly vulnerable ecosystems. ...
Wetland ecosystems and the fisheries that depend on them are vital to the survival of million individuals in poor nations. Although this habitat is contracting because of heavy pressure brought on by the expansion of the population and the increase of human activity in Cameroon. Yet it is crucial to evaluate the management practices used to ensure its durability. In this study, we look into wetland stakeholders' perspectives. Therefore, it is important to assess the management to make a strategic suggestion for the formulation of a national strategy. Totaling, 277 individuals were interviewed from the Rio del Rey, Ebogo, Barombi, and the Cameroonian portion of Ntem wetlands, and Dschang's municipal lake. The samples were taken utilizing a structured questionnaire between 4 February and 20 July 2001, when fishing was at its peak. Results show that 95.6% of management actors believe that this ecosystem is significant and valuable (χ 2 =21.965; ddl = 15; P=0.015); furthermore, the results show that 86.7% of respondents are unaware of any laws or other legal instruments that are currently in effect. From one site to another, there were substantial differences in how local management committees were seen (χ 2 =27.29; P<0.05). Additionally, various institutional issues discussed include the following: weak institutional cooperation (28%)> inadequate legislative policy (24%)> conflicts of interest (21%)> inadequate funding (18%)> lack of political will on the part of the authorities (6%%)> inadequately qualified people (3%). The study also shows that Cameroon's wetland suffers from a lack of adequate restrictions. Consequently, it is essential to implement wetland management strategy.
... These habitats include floodplains that may be closely associated with semi-permanent and permanent bodies of water, dry riverbeds that periodically become raging rivers, or completely isolated from permanent bodies of water and includes small rainwater pools that may exist for only a few weeks out of the year (Polačik & Podrabsky, 2015). Nevertheless, temporary wetlands play important role to enhance biodiversity and provide aesthetic, biogeochemical, and hydrologic functions (Calhoun et al., 2016). In fact, some fish species have evolved to stay in seasonal habitats, even require the periodic drying of their seasonal habitat and there is a relationship between the species composition with seasonal changes (Wolter & Bischoff, 2001;Okogwu, 2010;Tang et al., 2018). ...
Ephemeral waters, the temporary aquatic environment become an interesting habitat to explore extremophile organism, include phytoplankton. Furthermore, the waters have an acidic condition or low pH that impact to metabolisms, community structure, and diversity of phytoplankton. This study was conducted on June until August 2022 in Bangka Regency, Bangka Belitung Archipelago Province, Indonesia. We analyzed the phytoplankton presence at acidic ephemeral waters to indicated their potential as primary producer in food web, bioindicator, and ecological succession agent. This study was conducted by exploration method of phytoplankton diversity. The research observed and found five class and twelve genera that consist of class Chlorophyceae (genera Enteromorpha, Ankistrodesmus, Prasiola, Pleurococcus, and Coleochaete), class Rhodophyceae (genera Lemanea), class Diatoms (genera Diatoma, Synedra, and Navicula), class Xanthophyceae (genera Ophiocytium), and class Cyanobacteria (genera Oscillatoria and Anabaena). The class Chlorophyceae, genera Enteromorpha were the highest community at the both of acidic waters and they could survive at pH 3.52 + 0.5 to 3.71 + 0.8. Abstrak Perairan ephemeral, lingkungan perairan musiman menjadi suatu habitat yang menarik untuk mengeksplorasi organisme ekstremofil, termasuk fitoplankton. Lebih jauh lagi, perairan tersebut memiliki kondisi asam atau pH rendah yang berdampak pada metabolisme, struktur komunitas, dan diversitas fitoplankton. Penelitian ini dilaksanakan pada Juni hingga Agustus 2022 di Kabupaten Bangka, Provinsi Kepulauan Bangka Belitung, Indonesia. Kami menganalisis keberadaan fitoplankton di perairan ephemeral asam untuk mengindikasikan potensi fitoplankton sebagai produsen utama, bioindikator dan agen suksesi lingkungan. Penelitian ini dilaksanakan dengan metode eksplorasi diversitas fitoplankton. Penelitian ini mengobservasi dan menemukan lima kelas dan dua belas genus yang terdiri atas Enteromorpha adalah komunitas tertinggi pada kedua perairan asam dan mampu bertahan pada pH 3.52 + 0.5 to 3.71 + 0.8.
... Mountains, also called the world's "water towers," provide vital resources to a significant portion of the global population as a result of their high biodiversity at genetic, species, and ecosystem levels, and half of human population is dependent on mountain resources for various reasons and largely due to water needs (Egan & Price, 2017;Körner & Ohsawa, 2005). However, according to recent studied, high mountain ecosystems are more sensitive to climate change and will be more affected (Acuña et al., 2017;Beniston, 1994;Bolpagni et al., 2013;Calhoun et al., 2017;Cramer et al., 2018;Guisan et al., 1995;Kienast et al., 1998;Theurillat & Guisan, 2001). In relation to this, in the twentieth century, high-temperature averages were monitored in mountainous ecosystems due to global warming (Egan & Price, 2017). ...
Ephemeral streams are important habitats that support biodiversity, especially in mountainous ecosystems in arid and semi-arid regions, and are among those that will be most affected by global climate change. This study aimed to examine the trends in plant species diversity of ephemeral stream beds and their relationship with environmental variables (aspect, elevation, soil) in the eastern Mediterranean region.
For this purpose, 40 sample plots were applied in the valley cross sections of the ephemeral stream beds (valley bottom, side and ridge) on two main slopes (north and south) in 2019. The abundance values of plant species were determined and the number of individuals in each sample plot was counted. In addition, soil samples were taken at a depth of 0–30 cm and analyzed. With the data obtained, the importance value index of all species was calculated, and the diversity and species richness of the sample plots were determined.
A total of 130 plant taxa were identified in the study area. The most dominant species were Astragalus kurdicus (IVI value: 25.97), Helichrysum plicatum (21.94), Taeniatherum caput-medusae subsp. crinitum (15.51), Hordeum bulbosum (15.33), Bromus erectus (15.32), and Minuartia juniperina (14.14). Both plant richness and endemism rate showed a significant relationship with increasing elevation. Plant diversity values of south-facing slopes were higher (2.23) than those of north-facing slopes (2.21). In addition, we found that phosphorus is an important factor in the distribution of plant species along the ephemeral stream beds, and as the amount of phosphorus increases, species richness and diversity also increase.
... Inland ephemeral wetlands support a high level of biodiversity and provide valuable habitat for endemic and rare species (Capon 2003;Deil 2005). Despite their ecological, social, and economic significance, the quality and number of ephemeral wetlands is threatened by intensive anthropogenic pressures resulting in their rapid disappearance (Deil 2005;Calhoun et al. 2017). The driving factors of climate change and human population growth have tremendous potential for altering rainfall and runoff patterns. ...
Ephemeral wetlands are important ecologically but are often jurisdictionally complex and under-studied. Forms of local knowledge, including local ecological knowledge (LEK) and farmer knowledge, are increasingly recognised as able to complement other scientific knowledge for planning and management. This paper contributes to the discussion on the value and potential use of local knowledge by considering the Cowal system, an ephemeral wetland in dryland Australia. The Cowal system’s hydrological regime is highly variable, with drying and wetting cycles influenced by distant rainfall events. There is limited historical scientific data available for the system. Semi-structured interviews were undertaken with local landholders who privately own the land within the Cowal system. The aggregated results showcase their knowledge and understanding of the ecological functions of the Cowal system, highlight some current ephemeral wetland management activities and indicate their concerns for the future. LEK is shown to be a valuable source of historical and planning data. For example, their combined memories and family records of the Cowal system provide the only historical record of the timeline of the wetland’s filling and drying, and support their concerns about the alteration of the natural hydrological regime because of developments in the catchment area. The research suggests that LEK should be actively sought by scientists, managers, and planners of wetlands, especially where baseline and systems information is scant.
... These freshwater ecosystems are characterized by fluctuating hydrology, switching between dry and wet states in response to seasonally varying rainfall and evapotranspiration rates. Like other globally distributed wetland types, seasonal wetlands are disappearing (Dahl 2014;Davidson 2014;Calhoun et al. 2017;Evans et al. 2017) and those that remain are at landscape scales. For this reason, they experience direct and indirect effects of agricultural management (Swain et al. 2013), which may affect wetland size, shape, and connectivity (Johnston and McIntyre 2019), as well as plant community structure and species composition (Teuber et al. 2013;Medley et al. 2015;Boughton et al. 2016; Moges et al. 2017). ...
... The hydrology of seasonal pools, ponds, wet meadows, and flooded grasslands depends on the amount of precipitation; therefore, a decrease in accumulated rain determines the shortening of hydroperiods. Most of these ecosystems act as reservoirs of desiccation-tolerant species that are well adapted to the dry and wet phases (Williams 1997(Williams , 1998Calhoun et al. 2017; Thorat and Nath 2018). Small lentic environments such as potholes, wet meadows, and pools can support a great variety of both invertebrate and vertebrate species that avoid large permanent systems due to the presence of large predators (Wellborn et al. 1996;Heino et al. 2015). ...
Herbivores in wetlands are key organisms that shape the structure and composition of wetland plant communities (algae and vascular plants). The detritus produced by herbivory contributes to nutrient cycling and provides important resources for other organisms in the ecosystem. Due to their importance we decided to survey a set of 12 seasonal wetlands located in Andean Patagonian forests. We registered biotic and abiotic variables of each wetland and the diversity and abundance of herbivores. We found two groups of wetlands: short and long hydroperiod. Despite this, the structure of the communities was not related with hydroperiod length as well as the abundance and species composition. In particular, the abundance of herbivores was explained by chlorophyll, pH, dissolved oxygen, among others. Their diversity and abundance was (in decreasing order): rotifers, copepods, cladocerans, caddisflies, and amphibians. Probably the species found in these wetlands are well adapted to different hydroperiod regimens and even in short hydroperiods can complete their life cycle. The results found here do not match with the model of hydroperiod gradient, however other variables not measured here such as diversity and abundance of aquatic plants or predation by invertebrates could impact the composition and abundance of herbivores in these wetlands.
... about 59% less than that from the totally centralized system. This is caused by the recycling usage of gray water for irrigation, as well as greater nutrient retention and purification in more ditches and ponds through such processes as sedimentation, plant uptake, and microorganism consumption 31,32 . The wider variability of gray WF compared to green and blue WF is due to the uncertainty of the nutrient retention capability of ditches and ponds. ...
Rice farming threatens freshwater resources, while also being increasingly vulnerable to drought due to climate change. Rice farming needs to become more sustainable and resilient to climate change by improving irrigation drainage systems. Small water bodies, used to store drainage water and supply irrigation in traditional rice farming systems have gradually been abandoned in recent decades. This has resulted in a higher water footprint (WF) associated with rice farming due to increased freshwater usage and wastewater release, also leaving rice production more vulnerable to extreme weather events. Here, we propose how protecting and reactivating small water bodies for rice irri- gation and drainage can decrease rice production WF in China by 30%, save 9% of China’s freshwater consumption, increase irrigation self-sufficiency from 3% to 31%, and alleviate yield loss in dry years by 2–3%. These findings show that redesigning rice irrigation drainage systems can help meet water scarcity challenges posed by climate change.
... In the 21st century, as satellite remote sensing (RS) and Geographic Information System (GIS) technologies continue to evolve, they have proven to be invaluable tools in wetland distribution research. These technologies provide cost-effective solutions for monitoring shifts in wetland landscapes and contribute significantly to their effective management [18][19][20][21][22][23][24]. Numerous researchers are currently employing technology and wetland landscape ecology methods to investigate the evolutionary features of the wetland landscape pattern and the climate response to wetland changes. ...
Wetlands are vital ecosystems in the Tibetan plateau that play a crucial role in water conservation, flood storage, and biodiversity maintenance. They are sensitive to climate change and typically have high ecological and environmental quality levels due to minimal human disturbance. This study aimed to quantify landscape pattern changes within Nagqu Hangcuo National Wetland Park (NNWP) and identify the impact of climate on wetland change. Using remote sensing data from six periods (1990, 1995, 2000, 2005, 2010, and 2015), dynamic change analysis, landscape pattern analysis, and correlation analysis were employed to determine the evolutionary features of the wetland landscape and explore their relationship with climatic factors. The results showed that the total wetland area increased from 15.11 km2 in 1990 to 15.23 km2 in 2015. The meadow area increased the most among landscape types, primarily converted from swamps. The frag-mentation of NNWP’s landscape increased while diversity decreased and shape became more complex over 25 years. Meadows were more sensitive to climatic factors than other landscape types with correlation coefficients between wetland separation and sunshine duration being more significant than other climatic factors. Therefore, it is imperative to monitor landscape pattern changes and the effects of climate change to better protect wetland parks through long-term planning, suitable mechanisms, and advanced technology.
... Without clear definitions of what delineates these smaller habitat features, it is even more challenging to create public awareness, enact legislation, and enforce protection [15]. Furthermore, regulatory frameworks tend to focus on larger habitats, and protections for individual habitat features such as temporary water bodies and ancient and/or veteran trees are inconsistent and tend to lack rigor. ...
Loss of insect biodiversity is widespread, and in forests habitat loss is one of the major drivers responsible. Integrative forest management must consider the preservation and promotion of key habitat features that provide essential microhabitats and resources to conserve biodiversity alongside ecosystem functions and services.
... Wetlands can vary greatly in extent over seasonal timescales (Davidson et al., 2018). Temporary or ephemeral wetlands, that is wetlands where surface water largely disappears annually or with an undefined pattern, perform a range of biological, biogeochemical and hydrological functions within the landscape (Allen et al., 2020;Calhoun et al., 2017;Zedler, 2003). The cyclical drying and rewetting plays an important role in enhancing biodiversity and provides a habitat for many protected flora and fauna. ...
Characterizing ephemeral karstic wetlands through hydrological modelling is key for sustainable protection of their ecosystems and to understand and mitigate the impact of flooding events. UISCEmod is a new open-source software for modelling water level time series, focused on ephemeral karstic wetlands, that requires minimal input information. UISCEmod contains both experimental and lumped hydrological models, and the calibration process is automated following a Bayesian approach. The main outputs of UISCEmod include volume, stage, inflow and outflow model time series, calibrated model parameters, and the associated uncertainties. UISCEmod was evaluated at 16 representative sites in Ireland obtaining Nash-Sutcliffe Efficiency (NSE) and Kling-Gupta Efficiency (KGE) above 0.85 for both stage and volume time series for most of the sites, showing its potential for covering the need for a simple, pragmatic, and flexible framework for modelling water levels in ephemeral karstic wetlands with relatively limited input data requirements.
... These freshwater ecosystems are characterized by fluctuating hydrology, switching between dry and wet states in response to seasonally varying rainfall and evapotranspiration rates. Like other globally distributed wetland types, seasonal wetlands are disappearing (Dahl 2014;Davidson 2014;Calhoun et al. 2017;Evans et al. 2017) and those that remain are at landscape scales. For this reason, they experience direct and indirect effects of agricultural management (Swain et al. 2013), which may affect wetland size, shape, and connectivity (Johnston and McIntyre 2019), as well as plant community structure and species composition (Teuber et al. 2013;Medley et al. 2015;Boughton et al. 2016; Moges et al. 2017). ...
Seasonally inundated wetlands are threatened ecosystems worldwide and increasingly important targets for wetland restoration programs. However, restoring such ecosystems is difficult, as it requires mimicking the historical shifts between dry and flooded states. In this study, we evaluate the responses of agriculturally impacted seasonal wetlands to pasture-scale hydrological restoration. We selected 15 seasonal wetlands in central Florida (10 within restoration easements and five in unrestored pastures) and excluded cattle from five of the restored wetlands. We monitored each wetland from 2011 to 2016 to document potential changes in water levels, plant species richness, beta diversity, floristic quality, and cover of obligate wetland species. Vegetation responses to restoration were gradual and subtle, becoming detectable only five years following restoration. By 2016, restored wetlands had significantly lower cover of facultative upland species and higher cover of obligate wetland species. Species richness was higher in unrestored wetlands due to the presence of many facultative upland species. Beta diversity within wetlands and floristic quality based on coefficient of conservatism were not affected by restoration. We did not find strong effects of cattle exclusion on post-restoration diversity metrics, but we observed a large increase in the native grass, Panicum hemitomon Schult. This study showed mixed outcomes when measured against the goals of restoring wetland communities. It also highlighted the need for more active restoration approaches to regain historical communities or promote target species (e.g. Coleataenia abscissa (Swallen) LeBlond). We emphasize the need for costly restoration activities to be coupled with long-term monitoring to assess success.
... In all models, the fractions representing shared effects were generally large. Although both groups of variables significantly influence the spatial patterns of snail assemblages, the climatic variables appeared to explain the variation more effectively than did the local environmental variables ( (Calhoun et al., 2017;Hotaling et al., 2017;Stenert et al., 2020). Plain. ...
A central goal of community ecology and biogeography involves understanding the spatial patterns of organisms and their underlying mechanisms. Understanding how the structure of wetland biomes vary throughout geographical or climatic gradients has critical implications for the ecological restoration and management of wetlands. However, the geographical patterns of snails in freshwater wetlands and the relative contributions of climatic and local environment variables remain poorly elucidated.
We investigated 126 freshwater wetlands across four ecoregions (Da Xing'an Mountains, Songnen Plain, Sanjiang Plain and Changbai Mountains) in Northeast China, and collected 105578 individual snails (Mollusca: Gastropoda) belonging to 17 families, 34 genera and 64 species.
Overall, snail richness and functional alpha diversity was higher in the wetlands of the Sanjiang Plain than the other three regions. Multivariate analyses results revealed that the taxonomic, functional and phylogenetic structures of snail assemblages differed significantly across the four regions. Higher taxonomic dissimilarities, as well as functional and phylogenetic dissimilarities existed between the wetlands of the Songnen Plain and the other three regions.
The variations in taxonomic, functional and phylogenetic structures of snail assemblages were predominantly explained by climatic variables rather than by local environmental variables. For taxonomic structure, salinity explained the greatest variation among all variables, whereas precipitation seasonality explained the greatest variation for functional and phylogenetic structure.
Considering extant patterns in assemblage structure and its predictors, aggravated salinization and seasonality of precipitation are expected to act as powerful factors shaping future assemblages. Also, climate‐related factors cause changes and spatial distribution of invertebrate assemblages of freshwater wetlands should be considered to formulate differentiated strategy for biodiversity conservation.
... On the other hand, combining empirical information about landscape structure and species dispersal abilities with theoretical simulations may represent a straightforward approach to guiding management decisions (Brooker et al., 1999;Haddad et al., 2017b;Resasco et al., 2017). Landscapes in general, and particularly pondscapes, are in a threatening scenario due to global change and human activities (Wood et al., 2003;Calhoun et al., 2017;Hill et al., 2021). The present contribution attempts to advance those landscape features that may support biodiversity and should be explicitly considered both for understanding the ecological mechanisms and preserving biodiversity. ...
The spatial isolation gradient of communities and the gradient in the species dispersal ability are recognized as determinants of biodiversity in metacommunities. In spite of this, mean field models, spatially explicit models, and experiments were mainly focused on idealized spatial arrangements of communities leaving aside the combining role of dispersal and isolation gradients in metacommunity processes. Consequently, we have an incipient understanding of the role of the real spatial arrangement of communities on biodiversity patterns. We focus on six metacommunities for which confident information about the spatial arrangement of water bodies is available. Using coalescent metacommunity models and null models that randomize the location of water bodies, we estimated the potential effect of the landscape on biodiversity and its dependence on species dispersal ability. At extremely low or high dispersal abilities, the location of ponds does not influence diversity because different communities are equally affected by the low or high incoming dispersal. At intermediate dispersal abilities, peripheral communities present a much lower richness and higher beta diversity than central communities. Moreover, metacommunities from real landscapes host more biodiversity than randomized landscapes, a result that is determined by the heterogeneity in the geographic isolation of communities. In a dispersal gradient, mass effects systematically increase the local richness and decrease beta diversity. However, the spatial arrangement of patches only has a large importance in metacommunity processes at intermediate dispersal abilities, which ensures access to central locations but limits dispersal in isolated communities. The ongoing reduction in spatial extent and simplification of the landscape may consequently undermine the metacommunity processes that support biodiversity, something that should be explicitly considered in preserving and restoring strategies.
... The swamps and temporary wetlands where many of these animals inhabit have been drastically destroyed, due to deforestation, drainage, and landfilling resulting from agricultural and urban expansion (Loureiro et al. 2018;Castro and Polaz 2020). Loss of temporary wetlands from land alterations has significant ecological and social consequences (Calhoun et al. 2017), but freshwater research, policy, and conservation have historically neglected these habitats, focusing instead on larger water bodies and flagship species (Junk et al. 2014;Grasel et al. 2018;Hill et al. 2021). ...
Leptopanchax opalescens is a critically endangered small annual fish. Reproductive traits of this species were studied to improve our understanding of the strategies that facilitate the occupation of temporary wetlands. We compiled egg diameter and maximum total length data from 136 neotropical killifishes (Rivulidae) to establish comparisons between species with different life histories. We tested the hypothesis that annual killifishes have smaller body sizes and eggs than non-annual killifishes, which may be associated with different life spans and embryonic diapause. Fish were collected from the Guandu River Hydrographic Region (southeastern Brazil). DNA barcoding was employed to confirm the species’ identity. The phases of gonadal development and spawn type were described using histological techniques. Egg size and fecundity were determined. Females with batch spawning and males with continuous spawning were detected. The batch fecundity ranged from 22 to 32 vitellogenic oocytes (mean 27 ± 7 SD). Maximum body size was similar between the two life cycles (p = 0.24), but egg size was smaller for annual killifishes (p < 0.001). Spawning in batches, synchronous modal development of oocytes, continued production of sperm in males, and a complex process of embryonic diapause are reproductive traits that favor the resilience of L. opalescens and other annual fish in temporary wetlands. We conclude that body size is not related to lifespan and that factors underlying the selection of different egg sizes between annual and non-annual killifish species may be associated with different life history strategies to deal with stressful habitats.
... Also alarming is the decline in the wetland cover of the metropolis. Healthy and functioning wetlands play important roles such as flood regulation, water purification, and habitat for diverse species, among other services (Calhoun et al., 2017;Camacho-Valdez et al., 2014;Clarkson et al., 2013;Ivčević et al., 2021), which are critical to a safe and resilient city. Given that wetlands and low-lying areas of the metropolis frequently received runoff water and floods during the peak of the wet season, common wetland vegetation such as grasses and shrubs grew sparsely in these areas. ...
Green spaces are fast depleting in many urban areas across the world. This contributes to carbon dioxide emissions and affects the local climate and well-being of city residents. Yet, there is limited empirical research on the spatio-temporal patterns of change in urban green spaces and linkages to human well-being, especially in coastal cities where urban green spaces additionally act as critical flood controls. This paper assesses the changing pattern of green space cover in Cape Coast Metropolis and the factors associated with the perceived well-being of residents. Using a mixed-methods design, we obtained open-source geospatial data and gathered primary data through field observations, and in-depth and semi-structured interviews. These data were analysed using geospatial, statistical, and textual techniques. The results show that, from 1991 to 2018, the metropolis lost 26.57 sq.km (21.66%) of its green space cover. The major land use change observed is the conversion of green spaces and wetlands into built-up areas. The well-being of residents related to green space use in the metropolis is associated with individuals' age and gender; the presence of good quality green space, its accessibility, and perceived importance; frequency of visits; and the time spent in the green space. The findings suggest the need for the integration of nature into urban development planning and policy, and enforcement of development controls to protect green spaces and enhance the well-being of residents.
... El recambio calculado en ambas escalas mostró índices de Whittaker globales más altos que los reportados previamente a nivel regional para los humedales costeros de Lima (Aponte 2018), lo que significa que el humedal presentó un mayor recambio en su interior que el observado entre todos los demás humedales de la costa de Lima. Esto, junto con el valor más alto de especies por hectárea para la región, demuestran que este hábitat merece atención para su conservación, incluso por encima de áreas de mayor tamaño, tal como se ha hipotetizado para ecosistemas pequeños (Calhoun et al. 2017). Los estudios sobre lugares de descanso de aves migratorias y conjuntos de plantas raras muestran que los pequeños humedales son áreas críticas para la existencia continua de ambos grupos (McCulloch et al. 2003, Richardson et al. 2015, lo que aporta más evidencias sobre la necesidad de conservación de estos ecosistemas. ...
Wetlands in the developing world are disappearing due to bad management and urban growth, threatening the birdlife that inhabits them. The Huacho-Hualmay-Carquin wetland is located on Peru’s central coast, it has recently begun to be researched. Yet, it’s already losing ground to urbanization and public beachside development. 12 bird censuses (with two simultaneous transects: “supralittoral” and “urban”) were conducted; bird diversity and its correlation with 2 thermal-related oceanic parameters of the South Pacific (SST and ICEN) were calculated. Seventy-eight bird species were found, with abundances as high as 19,000 individuals. Species richness and abundance were higher in the supralittoral transect, while diversity was higher in the urban transect. We found correlations between the alpha diversity and abundance with both the SST and ICEN. This ecosystem exhibits high bird diversity and demonstrates the importance of studying small wetlands, as means of developing better management and conservation strategies in the region.
... Scattered ponds are important parts of the mosaic of cultural landscapes that provide suitable habitats for many species, including amphibians (Calhoun et al., 2017;Cogălniceanu et al., 2012;Hartel and von Wehrden, 2013). From a conservation point of view, these ponds and the amphibian species inhabiting them deserve considerable attention because they are vulnerable elements of the landscape in the era of global change (Blaustein and Kiesecker, 2002;Nori et al., 2015). ...
"As habitat loss poses challenge to conservation, it is becoming increasingly important to address questions about the extent to which connectivity between habitat patches is changing, and how this affects the local population of different species in these patches. The objective of our research was to monitor ponds and the pond-breeding amphibian species in a protected area. Therefore, we conducted day and night surveys, and compare the data collected in 2022 with the results of the latest available survey (2019), to simulate the patch occupancy of amphibian species over a 25-year timeframe. We found that combining the species occupancy data collected from both day and night surveys lead to higher patch occupancy values and higher number of registered individuals, compared to data collected only during daytime. The number of ponds decreased from 2019 to 2022, and further habitat loss could result in the disappearance of the local population if the area continues to dry out. Climate and landscape change could be major contributors to habitat loss in the future, therefore, in order to ensure the persistence of these local populations, we recommend the development of climate and habitat scenarios, and the planning of conservation measures based on these scenarios. Keywords: amphibian conservation, Transylvanian Plain, SPOM"
... Temporary ponds are one of the most common water bodies in the world (Downing et al., 2006;Wetzel, 1990), and a type of ecosystem that harbours high biological diversity (Calhoun et al., 2017). ...
• Many aquatic invertebrates that inhabit temporary ponds produce resting forms to overcome the dry period, building up the egg bank. When the wet phase returns, the resting forms hatch and the community is restored, and then pioneer species may have a major influence on how the pond community will assemble. We aimed to evaluate the diversity of an initial pond metacommunity by comparing the early active metacommunity collected in the field and the egg bank metacommunity (by carrying out a hatching experiment) of 32 Mediterranean temporary ponds. We hypothesised that both metacommunities would be similar but also that species turnover may play an important role, and that γ diversity would be similar with both approaches.
• After the identification and counting of rotifers and crustaceans in both metacommunities (i.e. the field vs. the experiment) we performed a Partial Triadic Analysis comparing the field metacommunity with those corresponding to each of the eight times the hatching experiment was checked for hatchlings. Furthermore, we compared the field and experimental metacommunities with a PROTEST analysis and identified the taxa responsible for differences between metacommunities with a SIMPER analysis. We assessed γ diversity using a size-based rarefaction curve and an evenness profile and explored β diversity and its components (turnover and nestedness) for the two metacommunities.
• Our experimental results showed differences in the temporal pattern of emergence between groups of organisms, with copepods, rotifers, and anostracans appearing first, but ostracods and rotifers reaching the highest diversity at the end of the experiment. The active and experimental pioneer metacommunities were similar according to a Procrustes analysis. Nevertheless, β diversity was high in both metacommunities and the differences among ponds and between both assemblages were mostly explained by species turnover.
• Both the active and experimental pond metacommunities showed some exclusive species that may be more difficult to uncover with only one type of approach. Furthermore, the high β diversity observed indicates that each temporary pond is an important contributor to γ diversity in the metacommunity.
• These results show that hatching experiments provide information that is complementary to standard sampling of the active community, and consequently is a useful tool to uncover pond biodiversity.
... Fishless, ephemeral wetlands are the preferred breeding habitat for many amphibian species including northern leopard frogs (Kendell, 2002). However, over recent decades, the abundance and quality of ephemeral wetlands across the landscape have declined due to anthropogenic impacts including climate change, draining for agricultural purposes, and introduction of exotic species (Calhoun et al., 2017). These changes may force amphibians to breed in suboptimal habitat, thereby altering their in- ...
The role of parasites can change depending on the food web community. Predators, for instance, can amplify or dilute parasite effects on their hosts. Likewise, exposure to parasites or predators at one life stage can have long‐term consequences on individual performance and survival, which can influence population and disease dynamics. To understand how predators affect amphibian parasite infections across life stages, we manipulated exposure of northern leopard frog (Rana pipiens) tadpoles to three predators (crayfish [Orconectes rusticus], bluegill [Lepomis macrochirus], or mosquitofish [Gambusia affinis]) and to trematode parasites (Echinostoma spp.) in mesocosms and followed juveniles in outdoor terrestrial enclosures through overwintering. Parasites and predators both had strong impacts on metamorphosis with bluegill and parasites individually reducing metamorph survival. However, when fish were present, the negative effects of parasites on survival was not apparent, likely because fish altered community composition via increased algal food resources. Bluegill also reduced snail abundance, which could explain reduced abundance of parasites in surviving metamorphs. Bluegill and parasite exposure increased mass at metamorphosis, which increased metamorph jumping, swimming, and feeding performance, suggesting that larger frogs would experience better terrestrial survival. Effects on size at metamorphosis persisted in the terrestrial environment but did not influence overwintering survival. Based on our results, we constructed stage‐structured population models to evaluate the lethal and sublethal effects of bluegill and parasites on population dynamics. Our models suggested that positive effects of bluegill and parasites on body size may have greater effects on population growth than the direct effects of mortality. This study illustrates how predators can alter the outcome of parasitic infections and highlights the need for long‐term experiments that investigate how changes in host–parasite systems alter population dynamics. We show that some predators reduce parasite effects and have indirect positive effects on surviving individuals potentially increasing host population persistence. Using an amphibian‐trematode model system, our study demonstrates that predators can alter the outcome of parasitic infections and highlights the need for long‐term experiments that investigate how changes in host‐parasite systems alter population dynamics. Predator identity matters; some predators reduce parasite effects and have indirect positive effects on surviving individuals increasing host population persistence.
... One of the main problems encountered affects the reduction and disappearance of biological diversity, a consequence of habitat modification, usually due to the conversion and degradation of wetlands [17]. The objectives in these cases are to promote the reduction of ecosystem stress through the identification of environmental problems in a diagnostic analysis, then Eng 2022, 3 388 establishing strategic action programs [18]. Normally, among the programmed strategies, public awareness campaigns are carried out to increase environmental awareness directed at different levels of society [19][20][21], including parliamentary workshops for politicians, training events for local government officials, scientific conferences, and the participation of scientists in research and reporting to university and high school students, sometimes conducting environmental camps [22]. ...
The LIFE SALINAS project, co-financed by the European Union, aims for the conservation and improvement of the protected area named the Regional Park of Las Salinas and Arenales de San Pedro del Pinatar (Region of Murcia, Spain). The main objectives are, among others, to stop the erosion of the dunes in front of a 500 m long beach and to expand the breeding habitat of aquatic birds. Between the dune and the beach, a barrier was placed to protect the dune from the effects of storms. The dunes were fenced, placed with sand traps and revegetation was carried out with native species in the most degraded areas. Within the salt pans, 1800 m of new sandy dikes were built to separate the salt ponds. The results have been the recovery of the dune ecosystem and the increase in the population of nesting aquatic birds and other species, as well as an increase in the quality and production of salt.
... Numerous studies have revealed the need to conserve and restore the spatial connectivity of wetlands in addition to simply maintaining wetlands in the landscape (e.g., Gibbs, 2000;Calhoun et al., 2017;Verheijen et al., 2018Verheijen et al., , 2020. This reflects an understanding of the importance of processes external to wetland habitat characteristics (e.g., hydrology, vegetative structure) that link wetland communities on the landscape, in addition to the unique characteristics internal to individual wetlands. ...
Wetland ecosystems are diverse, productive habitats that are essential reservoirs of biodiversity. Not only are they home to numerous wetland-specialist species, but they also provide food, water, and shelter that support terrestrial wildlife populations. However, like observed patterns of biodiversity loss, wetland habitats have experienced widespread loss and degradation. In order to conserve and restore wetlands, and thereby the biodiversity they support, it is important to understand how biodiversity in wetland habitats is maintained. Habitat heterogeneity and connectivity are thought to be predominate drivers of wetland biodiversity. We quantified temporal coherence (i.e., spatial synchrony) of wetland invertebrate communities using intra-class correlations among 16 wetlands sampled continuously over 24 years to better understand the relative influences wetland heterogeneity (i.e., internal processes specific to individual wetlands and spatial connectivity and external processes occurring on the landscape) on wetland biodiversity. We found that while wetlands with different ponded-water regimes (temporarily ponded or permanently ponded) often hosted different invertebrate communities, temporal shifts in invertebrate composition were synchronous. We also found the relative importance of internal versus external forces in determining community assembly vary depending on a wetland’s hydrologic function and climate influences. Our results confirm that heterogeneity and spatial connectivity of wetland landscapes are important drivers of wetland biodiversity.
... As such, a habitat structure of high vertical complexity qualifies as a 'keystone structure' for bird conservation in the eastern QTP (Tews et al., 2004;Manning et al., 2006). Keystone structures have been related to bird abundance and diversity in several habitat types, such as forests (Basile et al., 2021) or wetlands (Calhoun et al., 2017). Agricultural landscapes are known to host artificial keystone structures that positively contribute to biodiversity (Poschlod and Braun-Reichert, 2017), but their relevance in pastoral landscapes has been so far overlooked. ...
The post-2020 global biodiversity framework calls for a transformative change in food systems. Promoting agricultural multifunctionality is a viable approach to this sustainability transformation. The eastern Qinghai–Tibetan Plateau (QTP) is both one of the world’s largest livestock grazing systems and a hotspot of endemic birds in Asia. In this research, we aim to investigate the impact of livestock grazing on alpine bird assemblages at the local scale (alpha diversity) and their variation across the pastoral landscape (beta diversity). In the study area Nyanpo Yutse, we conducted surveys of 126 bird sample plots during two breeding seasons to acquire bird assemblage data. Meanwhile, we employed unmanned aerial vehicles to measure 2D and 3D habitat features within the 150-m radius. We investigated the key habitat variables driving the spatial distributions of both alpha and beta diversities of birds. Particularly, we partitioned beta diversity into its turnover and nestedness components and tested their patterns across sites of four levels of livestock grazing intensities (LGIs). Our results found no significant correlation between LGIs with species richness of birds, while 2D and 3D habitat complexity and built structure were positively correlated with alpha diversity (p < 0.05). At the landscape scale, pairwise LGI differences had no significant correlation (p > 0.05) with any pairwise beta diversity. The ordination plotting detected distinguished habitat preferences among 12 common birds and eight endemic birds. The multiple-site beta diversity of the 126 plots showed high species turnover (>0.871) where LGI was lower than 1.065 sheep units/ha, indicating the importance of moderate grazing for the conservation of diverse avian assemblages at the landscape scale. Our study demonstrated that extensive pastoralism is important for both maintaining the mosaic landscape and conserving avian biodiversity on the eastern QTP. We unveiled one of the ecological mechanisms through which synergies can be realized to support both agricultural production and biodiversity conservation in the Tibetan grazing system.
... Temporary wetlands branded by frequent aridity (typically completely parched, at least yearly) result in a distinct, highly specialised cluster of prevalent uncommon vegetation and species . Temporary wetlands have been documented across all geographies, including Antarctica (Antarctic liquefy ponds), and in a wide range of terrain contexts; nonetheless, temporary wetlands describe spatial distinctions since varied typologies are abundant in the area (Zedler, 2003;Williams, 2006;Calhoun et al., 2017). According to a global estimate, temporary water enclosed 0.81 million km2 in a recent period (i.e., 2015). ...
Temporary wetlands (TW) are distinguished by a distinct collection of uncommon and specialised flora and fauna species, modest size, periodical drying, and plentiful water during the flood season. The Indian subcontinent is home to a diverse range of freshwater, saline, and marine wetlands. The bulk of the inward wetlands are manmade or transitory, and they have traditionally been used by regional human groups. Most limnological research in India have focused on large, permanent bodies of water, pond ecosystems, and associated temporary wetlands.Furthermore, numerous Temporary Wetlands (TW) in Tamil Nadu State (TNS) offer significant potential for ecosystem service applications but are not yet well documented. Due to a lack of study, the existing survey explores the Ecological status (ES), distribution of Temporary Wetlands (TW), and individual wetland human disturbance score (HDS) in the Central Tamil Nadu district (CTND) in India. Seventy-five selected wetlands were surveyed using a variety of approaches in three districts: Karur, Namakkal, and Trichy. During the summer, all wetlands were hydrologically separated and parched.The TW size ranged from 1 to 10 acres, with 80 percent located in rural regions, 12 percent in semi-urban areas, and 8 percent in metropolitan areas. Wetland degradation was highest in Trichy district wetlands (TDW) at 76 percent Mid Impact (MI), followed by Namakkal district wetlands (NDW) at 36 percent MI, and Karur district wetlands (KDW) at 20 percent MI. Wetland degradation is often caused by landscape disturbance, buffer zone modification, hydrological alteration, pollution, and ecosystem alteration. The current study provides baseline facts on the biological state and distribution of Temporary Wetlands in CTND, which could help in the creation of provincial wetland management strategy. This method will fit other sections of TW and detect ecological status and human effect on wetlands, which will improve TW conservation and management decisions.
... This study further highlights the fact that the ecological footprint of an ephemeral breeding pool on the landscape is far greater than its size and hydroperiod would suggest. Ephemeral wetlands support distinct suites of plant and animal species, including vertebrate and invertebrate animals, many of which are declining or vulnerable and under threat from accelerating land development (Calhoun et al., 2017). The uncertainty and inconsistency surrounding regulatory protections of wetlands in the United States are only heightened for ephemeral wetlands (Waters et al., 2019). ...
Biotic and abiotic factors drive assortative mixing (preference for or sorting with individuals with similar characteristics) in animal populations on a landscape, with implications for dispersal, population structuring, and other ecological and evolutionary processes. However, patterns and generative mechanisms of assortative mixing are overlooked in amphibians outside of specific life history events such as reproduction. The aims of this project were to determine whether there is assortative mixing by size and life history category in eastern spadefoots (Scaphiopus holbrookii), whether these patterns are preserved across time and spatial scale, and quantify the nature and relative role of various habitat and soil features in explaining observed patterns in spatial organization of individuals. We conducted field surveys in southeastern Virginia, USA, in 2016 and 2017 during nonbreeding periods to create spatial networks of S. holbrookii. We quantified spatial assortativity by size and life history stage and evaluated the roles of multiple landscape features in explaining spatial organization of S. holbrookii. We found that S. holbrookii sorted spatially by size and sex outside of breeding periods, with juveniles and adults less likely to sort with each other. Within each life history stage, S. holbrookii sorted by size. These patterns were similar across time and spatial scale. Soil and habitat types had no effect on assortativity. Instead, the distance to nearest breeding pool, wetland, and meadow were related to life history stage assortativity, as well as size assortativity in males and subadults. Adult males and females displayed affinity for breeding pools and meadows and avoidance of other types of wetlands, while subadults and nonbreeding adults showed opposite patterns compared with breeding adults. Our results indicate that (1) previously established guidelines for the minimum size of buffer zones to protect wetland-breeding amphibians may be inadequate, (2) nonbreeding wetlands may be important core habitat for subadults, and (3) the upland spatial organization of amphibians may be used to predict locations of undetected breeding pools.
... Due to their natural heterogeneity, SWEs play a pivotal ecological role. First, they participate in hydrological and biogeochemical processes [2,7]. Second, they are considered a biodiversity hotspot, being an incredibly wide habitat with high species diversity [6,8]. ...
Small standing-Water Ecosystems (SWEs), despite their pivotal ecological role due to their participation in hydrogeological processes and their richness in biodiversity, seem to be often overlooked by the scientific community. In this study, the vascular plant diversity in some representative SWEs, that host a peculiar assemblage of plant and animal species, was investigated in relation to the disturbance effects of a wild horse population. A total of 50 plots, equally distributed in small and large SWEs, were surveyed and a level of disturbance was attributed to each plot. We found greater species richness in small and undisturbed SWEs, which suggests the negative impact of horse grazing on the richness of plant species in this type of habitat. Significant differences in plant assemblage were found according to the disturbance level, whereas, contrary to what was observed for species richness, no differences were detected based on their size. The diversity indices, used to evaluate the richness and diversity in these areas, recorded the highest values for small and undisturbed areas. This result highlights that the disturbance of the horse grazing plays a pivotal role in affecting the diversity and richness of species in the SWEs. These findings suggest that SWE systems should be analyzed considering these areas as unique in order to allow the conservation of the plant richness and biodiversity of the SWE systems in conjunction with the protection of horses.
Vernal pools are small temporary wetlands occurring in shallow depressions usually filled with precipitation in autumn and winter. They will dry seasonally, which makes them fishless ponds devoid of large aquatic predators. These ephemeral ponds are less studied compared to other freshwater ecosystems, such as lakes, although they are considered biodiversity hotspots. The aim was to study the use of vernal pools by birds and bats and compare this to permanent wetlands. We expected higher bat activity and bird abundance in vernal pools than permanent wetlands, and that is related to the spatial and temporal fluctuations of the emerging flying insects. However, no difference in bird abundance, diversity or community was found between the habitats. Regarding bats, the activity of Myotis spp was generally higher at lakes than vernal pools, while the activity of Eptesicus nilssonii increased during the study period regardless of habitat type. No relationship was found between the emergence of insects and the occurrence of bird and bats. Although, vernal pools were not more attractive habitats compared to lakes, they still form an important, largely neglected, diverse habitat type within the boreal landscape.
Accurate, unbiased wetland inventories are critical to monitor and protect wetlands from future harm or land conversion. However, most wetland inventories are constructed through manual image interpretation or automated classification of multi-band imagery and are biased towards wetlands that are easy to directly detect in aerial and satellite imagery. Wetlands that are obscured by forest canopy, that occur ephemerally, and that have no visible standing water are, therefore, often missing from wetland maps. To aid in the detection of these cryptic wetlands, we developed the Wetland Intrinsic Potential (WIP) tool, based on a wetland-indicator framework commonly used on the ground to detect wetlands through the presence of hydrophytic vegetation, hydrology, and hydric soils. Our tool uses a random forest model with spatially explicit input variables that represent all three wetland indicators, including novel multi-scale topographic indicators that represent the processes that drive wetland formation, to derive a map of wetland probability. With the ability to include multi-scale topographic indicators that help identify cryptic wetlands, the WIP tool can identify areas conducive to wetland formation while providing a flexible approach that can be adapted to diverse landscapes. For a study area in the Hoh River watershed in western Washington, USA, classification of the output probability with a threshold of 0.5 provided an overall accuracy of 91.97 %. Compared to the National Wetlands Inventory, the classified WIP tool output identified over 2 times the wetland area and reduced errors of omission from 47.5 % to 14.1 % but increased errors of commission from 1.9 % to 10.5 %. The WIP tool is implemented as an ArcGIS toolbox using a combination of R and Python scripts.
Ponds, the most numerous freshwater habitats globally, are becoming increasingly recognized as being important for rare, endemic and endangered species, owing to the high levels of biodiversity they support and their role in ecosystem services. However, they remain largely overlooked and widely excluded from policies that might protect them. Even though their size and permanence are highly important for their legal protection, these two characteristics are not precisely and universally defined in theory and in international legal documents.
International legislative frameworks do not seem to provide global, comprehensive, or detailed protection of ponds as significant and widespread habitats. On the contrary, they safeguard only fragmentary small water bodies – either by protecting certain types or only those that are parts of larger protected areas. Also, pondscapes are not specifically recognized as forms in need of legal protection.
In this paper, the complexity of the legal protection of ponds is presented, followed by recommendations. These should be transformed into legal norms, and given their number and complexity be presented within a single, unique convention that would specifically address the protection of ponds globally. This type of protection would be the most effective legal tool.
The widespread acceleration of freshwater salinisation due to human activities, such as pollution , resource extraction and urbanisation coupled with climate change, poses a significant threat to aquatic ecosystems. Limited work has been directed towards salinisation effects in temporary wetland systems. These systems are characterised by unique crustacean communities reliant on dormant egg production. We assessed salinisation effects on temporary wetland crustacean communities from semi-arid pans in the Khakhea-Bray Transboundary Aquifer region of South Africa using a laboratory-based approach. Sediment from pans containing crustacean resting eggs was exposed to water with varying salinities (0-10 ppt), and emergent hatchlings were assessed over a 30-day hydroperiod. At salinities of 2.5 ppt and above, there were significant decreases in emergent taxa richness and abundance. Spinicaudata and Ostracoda were the most sensitive taxa to high salini-ties. Cladocera, Copepoda, Notostraca and Anostraca hatchlings had shallower decreases with salinity, but hatchability still fell rapidly. There was a limited effect on community hatching phenology dynamics from salinity, with all taxa showing reduced hatch-ability over time overall, with the exception of Cla-docera which exhibited a clear unimodal response, peaking around 20 days post-inundation. This suggests that the main impact of salinisation in these systems will be reductions in hatching success and hence reduced recruitment, leading to changes in predation pressures, food web structure and functioning of these ecosystems, with implications for associated ecosystem services.
Large branchiopods are a key component of the fauna of temporary ponds and play an important role in the functioning of these vulnerable ecosystems. Owing to the establishment of new settlements and agricultural expansion, temporary ponds in Tanzania are disappearing at an alarming rate whilst little is known about their diversity and ecology. We contrasted temporary ponds from a protected area with those in communal lands to detect associations between land-use types and large branchiopod community structure. Six large branchiopod species were collected, five of which have been previously reported from Southern Africa, whilst one turned out to be new to science: Streptocephalus manyarensis n.sp. Kafula and Brendonck (2023). The clam shrimp Cyzicus sp., fairy shrimps Streptocephalus lamellifer Thiele (1900) and S. bourquinii Hamer and Appleton (1993) were the most abundant and widely occurring. Variation in large branchiopod community structure was explained by the presence of Nothobranchius killifish and orthophosphate concentration. The large branchiopod community structure was different in settlement and protected areas. Our study on the occurrence and structure of large branchiopod communities in relation to land-use types serves as a base for formulation of guidelines and management tools to regulate land-use practices adjacent to temporary pond ecosystems.
Habitat restoration frequently focuses on reaching an idealized steady state, but this is unrealistic for disturbance‐dependent ecosystems where temporal variability is inherent and habitat conditions are expected to fluctuate. Understanding the ways in which the outcomes of restoration change over time in disturbance‐dependent ecosystems can better inform adaptive management plans and increase the likelihood that restoration efforts will be effective. We conducted a decade‐long restoration experiment to test how restoration efforts to increase disturbance levels impact habitat quality and populations of an endangered butterfly over time. We show that changes in plant communities as a response to disturbance vary depending on time since restoration, with target host plants initially increasing and peaking several years post‐restoration but then declining. In the absence of further disturbance, butterfly population sizes follow a similar pattern, with population declines concurrent with declines in host plants. Due to this non‐linear response, management actions within disturbance‐dependent ecosystems need to include long‐term monitoring in order to accurately capture changes in habitat response, as well as active, adaptive planning that shifts according to current system stability. Restoration efforts within these dynamic habitats are more likely to succeed when temporal variability is explicitly tracked and multiple cycles of restoration are considered as part of management actions. This article is protected by copyright. All rights reserved.
Citation: Millikin, A.R.; Coster, S.S.; Welsh, A.B.; Anderson, J.T. Pool Age and Local Habitat Are Associated with Effective Number of Breeders in Spotted Salamander Populations Colonizing Created Vernal Pools. Diversity 2023, 15, 124. https:// Abstract: Population genetics can reveal whether colonization of created habitats has been successful and inform future strategies for habitat creation. We used genetic analysis to investigate spotted salamander (Ambystoma maculatum) colonization of created vernal pools and explored the impact of habitat characteristics on the genetic diversity and connectivity of the pools. Our first objective was to examine genetic structure, differentiation, diversity, and potential for a founder effect. Our second objective was to determine if habitat characteristics were associated with effective number of breeders, relatedness, or genetic diversity. We sampled spotted salamander larvae in 31 created vernal pools (1-5 years old) in Monongahela National Forest (WV) in May and June 2015 and 2016. The youngest pools exhibited genetic differentiation, a founder effect, and low effective number of breeders. Effective number of breeders was positively associated with pool age, vegetation cover, pool diameter, and sample size. Vegetation cover was also negatively associated with relatedness. Genetic diversity did not have strong environmental predictors. Our results indicated the effective number of breeders increased and genetic differentiation decreased within 4-5 years of pool creation, a sign of rapid colonization and potential population establishment. Our research also showed that higher vegetative cover within the pool and larger pool diameters could impact habitat quality and should be incorporated into future pool creation.
Wetlands are essential for life on Earth, but at the same time the most threatened environments due to the gradual alterations associated with climate change and human action. The botanical studies on wetland higher plants carried out in Italy from 1950 until today are analysed in this survey. The 1,265 contributions resulting from this study are analysed from a historical, geographical, and content point of view. Most of the scientific contributions were published in the 1980s and 1990s, often by the same research groups and on a local scale. The predominant research theme is the inventory. Most papers are mainly focused on lakes and rivers. The results of this literature survey point to the need to continue and intensify these studies, especially in southern Italy and in temporary wetlands. It is essential to make the huge amount of data resting in drawers or included in scientific reports but not published in scientific journals readily accessible. This could also be achieved through online geographical databases.
Accurate, un-biased wetland inventories are critical to monitor and protect wetlands from future harm or land conversion. However, most wetland inventories are constructed through manual image interpretation or automated classification of multi-band imagery and are biased towards wetlands that are easy to detect directly in aerial and satellite imagery. Wetlands that are obscured by forest canopy, occur ephemerally, and those without visible standing water are, therefore, often missing from wetland maps. To aid in detection of these cryptic wetlands, we developed the Wetland Intrinsic Potential tool, based on a wetland indicator framework commonly used on the ground to detect wetlands through the presence of hydrophytic vegetation, hydrology, and hydric soils. Our tool uses a random forest model with spatially explicit input variables that represent all three wetland indicators, including novel multi-scale topographic indicators that represent the processes that drive wetland formation, to derive a map of wetland probability. With the ability to include multi-scale topographic indicators, the WIP tool can identify areas conducive to wetland formation and provides a flexible approach that can be adapted to diverse landscapes. For a study area in the Hoh River Basin in Western Washington, USA, classification of the output probability with a threshold of 0.5 provided an overall accuracy of 91.97 %. Compared to the National Wetland Inventory, the classified WIP-tool output increased areas classified as wetland by 160 % and reduced errors of omission from 47.5 % to 14.1 %, but increased errors of commission from 1.9 % to 10.5 %. The WIP tool is implemented using a combination of R and python scripts in ArcGIS.
Small wetlands have a high conservation value due to their importance as biodiversity hot spots. Despite this, they are nowadays at risk due to global change variables. We surveyed a set of seasonal wetlands located in Andean Patagonian forests which are the less studied aquatic systems. The wetlands selected presented different degrees of human impact, and some of them were geographically close and others were faraway and insulated. We registered environmental variables and the diversity and abundance of common pond animals in each wetland. Wetlands were described performing a principal component analysis considering the environmental variables. The main explanatory variables were dissolved organic carbon, water color, total nitrogen, and depth of the wetlands. The diversity of the aquatic organisms was studied using the Shannon index, and the relationship between environmental variables and aquatic organism was analyzed using canonical correspondence analysis (CCA). The rotifers showed the greatest diversity in the zooplankton assemblage, and the trichopterans were the most diverse of the benthic groups studied. The CCA showed that different variables explained the distribution of zooplankton and caddisfly/amphibian larvae assemblages. Each wetland presented a particular assemblage of species, and shared few species among them. Despite the differences in human impact and geographical distance, none of these factors appears to influence the diversity of these wetlands. We postulate that the high environmental heterogeneity found in these wetlands drives the diversity and abundance pattern of the aquatic biota observed.
Leptopanchax opalescens is a critically endangered small annual fish. Reproductive traits of this species were studied to improve our understanding of the strategies that facilitate the occupation of temporary wetlands. We compiled egg diameter and maximum total length data from 136 neotropical killifishes (Rivulidae) to establish comparisons between species with different life histories. We tested the hypothesis that annual killifishes have smaller body sizes and eggs than non-annual killifishes, which may be associated with different life spans and embryonic diapause. Fish were collected from the Guandu River Hydrographic Region (southeastern Brazil). DNA barcoding was employed to confirm the species’ identity. The phases of gonadal development and spawn type were described using histological techniques. Egg size and fecundity were determined. Females with batch spawning and males with continuous spawning were detected. The batch fecundity ranged from 22 to 32 vitellogenic oocytes (mean 27 ± 7 SD). Maximum body size was similar between the two life cycles (p = 0.24), but egg size was smaller for annual killifishes (p < 0.001). Spawning in batches, synchronous modal development of oocytes, continued production of sperm in males, and a complex process of embryonic diapause are reproductive traits that favor the resilience of L. opalescens and other annual fish in temporary wetlands. We conclude that body size is not related to lifespan and that factors underlying the selection of different egg sizes between annual and non-annual killifish species may be associated with different life history strategies to deal with stressful habitats.
Ponds are aquatic habitats defined by their small size. Although small they are found on every continent, they are disproportionately rich in aquatic biodiversity, benefit terrestrial wildlife and have important ecosystem function benefits. One of these benefits might be carbon sequestration, a possibility suggested by (1) their abundance, (2) the intensity of their biogeochemical activity. Whilst greenhouse gas fluxes from ponds have been monitored widely, quantifying the stocks of organic carbon buried in sediment is a gap in our knowledge. Here we summarise measures of organic carbon in pond sediments cores from a diverse range of lowland ponds in England. We estimate a general measure of 9.38 kg OC in a 1 m² × 20 cm block of pond sediment and scale this up to an overall estimate for Great Britain of 2.63 million tons of OC in pond sediment, with 95% CI of 1.41 to 3.84 million tons. The relationship between sediment carbon and gas fluxes remains a significant unknown.
Les friches industrielles représentent de réelles opportunités pour la création d’espaces naturels mais les méthodes de restauration et d’évaluation des bénéfices environnementaux de ces opérations sont très lacunaires. L’objectif de cette thèse a été, au travers d’un cas d’étude, de palier à ce manque. Les résultats obtenus mettent en évidence que la restauration des technosols de friches industrielles nécessite une approche pluri-compartimentale (végétation et sol) et que les méthodes utilisées actuellement en restauration des sols sont moins efficaces dans des milieux aussi dégradés. Une approche pluridisciplinaire alliant outils d’évaluation économique et indicateurs écologiques a été ajustée permettant l’évaluation des bénéfices environnementaux de tels projets. Des adaptations sont cependant encore nécessaires dans la récolte de données, la sélection des indicateurs et la conception de la méthode pour garantir une meilleure prise en compte du compartiment sol, optimiser l’intégration des objectifs du projet de restauration et des potentiels impacts de la restauration sur les populations locales.
The Italian rice agroecosystem plays a key role in the European production and provides a unique range of rice varieties. As productive man-made wetlands, rice paddies are strategic and economic components in the habitat provision for migratory wildlife at the European scale. However, the characteristic of being a “temporary wetland” causes the creation of an ecological trap for a number of living organisms. For this reason, agricultural practices adopted for the management of rice paddies are essential to move towards more sustainable cultivations capable of promoting biodiversity and to minimising negative environmental impacts. This study proposes an ecologically-oriented strategy to implement a circular and self-regulating farming system designed considering the role of constructed wetlands in providing ecosystem services in rice agroecosystems. It demonstrates the economic feasibility and benefits provided by a self-regulating biosystem based on an integrated wetland for a small-size rice farm of the Vercelli province (Piedmont Region, Italy). The study was conducted in collaboration with the rice farm, which already experiments with organic farming techniques. The investigation focuses on the current management structure of the farm and develops an ecologically-oriented business strategy to sustain local biodiversity. This strategy rediscovers and improves the traditional co-culture technique through the development of a permanent pond. It explores the potential benefits generated by the approach, in terms of biodiversity conservation, biological control of pests and weeds and habitat provision for wildlife. The study presents a real case study of economic sustainability of the business strategy through financial analysis. The findings highlight promising economic outcomes compared to the conventional rice cultivation systems. The diversification of marketing strategy and the reduction of operating costs are key factors in the success of the strategy. The ecologically-oriented design methodology presented in this article can easily be applied to other small-scale farms in the agrifood sector.
Botswana constitutes a major gap in our knowledge of the distribution of Ostracoda in the region of Southern Africa, restraining thorough biogeographic interpretations. We combine records from previously published surveys along with our own field collections to provide a collation of living and fossil (Late Pleistocene to Holocene) Ostracoda recorded in Botswana. Our survey yielded 17 species, of which nine species have not been recorded before in the country. Including the present update, 54 species (45 living and nine fossil or subfossil) belonging to 22 genera of five families (with 76% species belonging to the family Cyprididae) are currently reported from Botswana. Yet, 23 taxa are left in open nomenclature, indicating the urgent need for sound systematic studies on harmonizing taxonomy of Southern African ostracods, especially of those inhabiting small temporary waterbodies, considered as threatened with extinction before being properly described or discovered. This updated checklist provides detailed information about the distribution and habitat of each recorded species. Species richness, distribution patterns, and diversity of ostracod species regionally and in different freshwater ecoregions are also discussed. We found low alpha (site) diversity (mean 3.3 species per site) and a significant difference in species composition and beta diversity of the Okavango ecoregion versus the Kalahari and Zambezian Lowveld ecoregions.
Inundation area is a major control on the ecosystem services provisioned by geographically isolated wetlands. Despite its importance, there has not been any comprehensive study to map out the seasonal inundation characteristics of geographically isolated wetlands over the continental United States (CONUS). This study fills the aforementioned gap by evaluating the seasonality or the long-term intra-annual variations of wetland inundation in ten wetlandscapes across the CONUS. We also assess the consistency of these intra-annual variations. Finally, we evaluate the extent to which the seasonality can be explained based on widely available hydrologic fluxes. Our findings highlight significant intra-annual variations of inundation within most wetlandscapes, with a standard deviation of the long-term averaged monthly inundation area ranging from 15 % to 151 % of its mean across the wetlandscapes. Stark differences in inundation seasonality are observed between snow-affected vs. rain-fed wetlandscapes. The former usually shows the maximum monthly inundation in April following spring snowmelt, while the latter experiences the maximum in February. Although the magnitude of inundation fraction has changed over time in several wetlandscapes, the seasonality of these wetlands shows remarkable constancy. Overall, commonly available regional hydrologic fluxes (e.g., rainfall, snowmelt, and evapotranspiration) are found to be able to explain the inundation seasonality at wetlandscape scale with determination coefficients greater than 0.57 in 7 out of 10 wetlandscapes. Our methodology and presented results may be used to map inundation seasonality and consequently account for its impact on wetland functions.
Mediterranean regions are biodiversity hotspots whose landscapes are characterized by evergreen sclerophyllous vegetation, mild-wet winters, and hot-dry summers. In the Northern Hemisphere, they occur in the Mediterranean Basin and California regions. In these areas, whose habitats are heavily shaped by centuries of anthropic activities, the main effects of climate change include a decrease in precipitation and change in its regime, a pronounced warming, an increase in frequency of extreme temperature events, and altered and intensified fire regimes. Climate change poses a double challenge to the regeneration from seeds of Mediterranean plants. Warmer winters mainly affect the seed germination phase by limiting “typical” Mediterranean cold-cued germination in autumn/winter and reducing overwinter dormancy release for those species whose seeds germinate in spring. Harsher summers are detrimental for the establishment phase, compromising seedling survival. However, evidence of phenotypic plasticity in some Mediterranean plants suggests potential adaptation to a changing climate in the short- to medium-term for species of these regions.
Playas are the dominant wetland type on the Southern High Plains of Texas and capture runoff during periods of heavy rainfall. Observing the hydrologic functions of playa is important to evaluate their ecological services, which include encouragement of species biodiversity and recharge of the underlying High Plains (Ogallala) Aquifer. Ten pairs of playas were chosen in 10 counties on the Texas Southern High Plains. Each pair included 1 playa surrounded by natural grassland (not in the Natural Resources Conservation Service’s Conservation Reserve Program) and 1 playa surrounded by cultivated cropland. Instrumentation at each playa allowed calculation of changes in free water evaporation and water stored over time during the hydroperiods, defined as continuous durations of surface water storage in the playa basins, caused by one or more rainfall events that generated sufficient runoff flows to reach and fill the playas. A water budget model calculated daily infiltration flux through the playa bottoms. Six cropland playas and 3 grassland playas had significant hydroperiods with associated consistent instrumentation operation during the 6-year study across the years 2005 to 2011. The average observed infiltration flux rates were approximately 10 millimeters/day (range 2 to 20 millimeters/day) and 3 millimeters/day (range 1 to 5 millimeters/day) for the cropland and grassland playas, respectively. The preliminary results may be influenced by the presence of eroded sediments from the surrounding cropland, but more runoff events are needed to differentiate between the impacts of playa floor soils and variations in rainfall and playa watershed characteristics that contribute to the hydroperiods. Citation: Ganesan G, Rainwater K, Gitz D, Hall N, Zartman R, Hudnall W, Smith L. 2016. Comparison of infiltration flux in playa lakes n grassland and cropland basins, Southern High Plains of Texas. Texas Water Journal. 7(1):25-39. Available from: https://doi.org/10.21423/twj.v7i1.7007.
Effective natural resource policy depends on knowing what is needed to sustain a resource and building the capacity to identify, develop, and implement flexible policies. This retrospective case study applies resilience concepts to a 16-year citizen science program and vernal pool regulatory development process in Maine, USA. We describe how citizen science improved adaptive capacities for innovative and effective policies to regulate vernal pools. We identified two core program elements that allowed people to act within narrow windows of opportunity for policy transformation, including (1) the simultaneous generation of useful, credible scientific knowledge and construction of networks among diverse institutions, and (2) the formation of diverse leadership that promoted individual and collective abilities to identify problems and propose policy solutions. If citizen science program leaders want to promote social-ecological systems resilience and natural resource policies as outcomes, we recommend they create a system for internal project evaluation, publish scientific studies using citizen science data, pursue resources for program sustainability, and plan for leadership diversity and informal networks to foster adaptive governance.
Given the complexity and multiplicity of goals in natural resource governance, it is not surprising that policy debates are often characterized by contention and competition. Yet at times adversaries join together to collaborate to find creative solutions not easily achieved in polarizing forums. We employed qualitative interviews and a quantitative network analysis to investigate a collaborative network that formed to develop a resolution to a challenging natural resource management problem, the conservation of vernal pools. We found that power had become distributed among members, trust had formed across core interests, and social learning had resulted in shared understanding and joint solutions. Furthermore, institutions such as who and when new members joined, norms of inclusion and openness, and the use of small working groups helped create the observed patterns of power, trust, and learning.
Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bodies to create spatial and temporal heterogeneity in the timing, flow paths, and magnitude of network connectivity. These attributes signal a critical role for GIWs in sustaining a portfolio of landscape functions, but legal protections remain weak despite preferential loss from many landscapes. GIWs lack persistent surface water connections, but this condition does not imply the absence of hydrological, biogeochemical, and biological exchanges with nearby and downstream waters. Although hydrological and biogeochemical connectivity is often episodic or slow (e.g., via groundwater), hydrologic continuity and limited evaporative solute enrichment suggest both flow generation and solute and sediment retention. Similarly, whereas biological connectivity usually requires overland dispersal, numerous organisms, including many rare or threatened species, use both GIWs and downstream waters at different times or life stages, suggesting that GIWs are critical elements of landscape habitat mosaics. Indeed, weaker hydrologic connectivity with downstream waters and constrained biological connectivity with other landscape elements are precisely what enhances some GIW functions and enables others. Based on analysis of wetland geography and synthesis of wetland functions, we argue that sustaining landscape functions requires conserving the entire continuum of wetland connectivity, including GIWs.
Linderiella baetica n. sp. (Anostraca, Chirocephalidae), is described from a temperate Mediterranean climate, episodic temporary fresh water body in Puerto Real (Cádiz, South Spain). Linderiella baetica n. sp. is characterized by the display of the shape of the basomedial outgrowth on the male second antenna, margin structure of praepipods, structure of medial margin of en do pod, penis basal projections, horn-like process on the inner side of the female antenna, female genital somites and of a combination of morphological features involving egg morphology. The study includes a morphological analysis using optical and scanning electron microscopes. Based on the diff erential diagnosis, a dichotomous key for males, females and resting eggs to Linderiella species is proposed. The diagnosis is complemented with phenology of the species and accompanying fauna and aquatic vegetation, and physico-chemical evolution of water along monitoring. © Publications Scientifiques du Muséum national d'Histoire naturelle, Paris.
Earth’s climate is changing, and by the end of the 21st century in Europe, average temperatures are likely to have risen by at least 2 °C, and more likely 4 °C, with associated effects on patterns of precipitation and the frequency of extreme weather events. Attention among policy-makers is divided about how to minimise the change, how to mitigate its effects, how to maintain the natural resources on which societies depend and how to adapt human societies to the changes. Natural systems are still seen, through a long tradition of conservation management that is largely species-based, as amenable to adaptive management, and biodiversity, mostly perceived as the richness of plant and vertebrate communities, often forms a focus for planning. We argue that prediction of particular species changes will be possible only in a minority of cases but that prediction of trends in general structure and operation of four generic freshwater ecosystems (erosive rivers, depositional floodplain rivers, shallow lakes and deep lakes) in three broad zones of Europe (Mediterranean, Central and Arctic-Boreal) is practicable. Maintenance and rehabilitation of ecological structures and operations will inevitably and incidentally embrace restoration of appropriate levels of species biodiversity. Using expert judgement, based on an extensive literature, we have outlined, primarily for lay policy makers, the pristine features of these systems, their states under current human impacts, how these states are likely to alter with a warming of 2 °C to 4 °C and what might be done to mitigate this. We have avoided technical terms in the interests of communication, and although we have included full referencing as in academic papers, we have eliminated degrees of detail that could confuse broad policy-making.
Evidence is mounting that evolutionary change can occur rapidly and may be an important means by which species escape extinction in the face of global change. Consequently, biologists need to incorporate evolutionary thinking into management decisions in conservation and restoration ecology. Here, we review the genetic and demographic properties that influence the ability of populations to adapt to rapidly changing selective pressures. To illustrate how evolutionary thinking can influence conservation and restoration strategies, we compare the potential of two California plant communities (vernal pools and blue oak woodlands) to evolve in response to global change. We then suggest ways in which restoration biologists can manipulate the genetic architecture of target populations to increase their ability to adapt to changing conditions. While there may not be any universal rules regarding the adaptive potential of species, an understanding of the various processes involved in microevolution will increase the short- and long-term success of conservation and restoration efforts.
We explore the category “geographically isolated wetlands” (GIWs; i.e., wetlands completely surrounded by uplands at the local scale) as used in the wetland sciences. As currently used, the GIW category (1) hampers scientific efforts by obscuring important hydrological and ecological differences among multiple wetland functional types, (2) aggregates wetlands in a manner not reflective of regulatory and management information needs, (3) implies wetlands so described are in some way “isolated,” an often incorrect implication, (4) is inconsistent with more broadly used and accepted concepts of “geographic isolation,” and (5) has injected unnecessary confusion into scientific investigations and discussions. Instead, we suggest other wetland classification systems offer more informative alternatives. For example, hydrogeomorphic (HGM) classes based on well-established scientific definitions account for wetland functional diversity thereby facilitating explorations into questions of connectivity without an a priori designation of “isolation.” Additionally, an HGM-type approach could be used in combination with terms reflective of current regulatory or policymaking needs. For those rare cases in which the condition of being surrounded by uplands is the relevant distinguishing characteristic, use of terminology that does not unnecessarily imply isolation (e.g., “upland embedded wetlands”) would help alleviate much confusion caused by the “geographically isolated wetlands” misnomer.
Genetic pollution of a native species through hybridization with an invasive species poses an insidious conservation threat. To expose genetic pollution, molecular methods employing multilocus data are required. We present a case study of genetic pollution via hybridization of a native crested newt species, Triturus cristatus, by the invasive Triturus carnifex on the Veluwe in the Netherlands. We sequenced 50 nuclear markers by next generation sequencing and one mitochondrial marker by Sanger sequencing for four populations from the native range of both parent species and eleven ponds on the Veluwe. We use three population genetic approaches (HIest, BAPS and Structure) to determine the genetic composition of the Veluwe newts based on all nuclear markers, a subset of 18 diagnostic markers and the complementary 32 non-diagnostic markers, with and without parental populations. BAPS underestimates genetic pollution, whereas Structure is comparatively accurate compared to HIest, although Structure’s relative advantage decreases with the diagnosticity of the markers. Data simulation confirms these findings. Genetic composition of the Veluwe ponds ranges from completely native, via different degrees of genetic admixture, to completely invasive. The observed hybrid zone appears to be bimodal, suggesting negative selection against hybrids. A genetic footprint of the native species is present in invasive populations, evidencing that the invasive locally replaced the native species. Genetic pollution is currently confined to a small area, but the possibility of further expansion cannot be excluded. Removal of genetic pollution will not be easy. We emphasize the need for legal guidance to manage genetic pollution.
Quantifying spatial and temporal heterogeneity in ecosystem processes presents a challenge for con-serving ecosystem function across landscapes. In particular, many ecosystems contain small features that play larger roles in ecosystem processes than their size would indicate; thus, they may represent ''hotspots'' of activity relative to their surroundings. Biogeochemical hotspots are characterized as small features within a landscape that show comparatively high chemical reaction rates. In northeastern forests in North America, vernal pools are abundant, small features that typically fill in spring with snow melt and precipitation and dry by the end of summer. Ephemeral flooding alters soil moisture and the depth of the soil's oxic/anoxic boundary, which may affect biogeochemical processes. We studied the ef-fects of vernal pools on leaf-litter decomposition rates, soil enzyme activity, and denitrification in vernal pools to assess whether they function as bio-geochemical hotspots. Our results indicate that seasonal inundation enhanced leaf-litter decompo-sition, denitrification, and enzyme activity in vernal pools relative to adjacent forest sites. Leaves in sea-sonally flooded areas decomposed faster than leaves in terra firme forest sites. Flooding also influenced the C, N, and P stoichiometry of decomposing leaf litter and explained the variance in microbial extracellular enzyme activity for phosphatase, b-D-glucosidase, and b-N-acetylglucosaminidase. Addi-tionally, denitrification rates were enhanced by seasonal flooding across all of the study pools. Col-lectively, these data suggest that vernal pool eco-systems may function as hotspots of leaf-litter decomposition and denitrification and play a signif-icant role in decomposition and nutrient dynamics relative to their size.
Vernal pools provide critical breeding habitat for amphibians adapted to temporary waters, but they seldom receive the same level of protection as permanent wetlands. In response to continued degradation and loss of pools, man-agers often attempt to mitigate losses through pool creation or restoration. However, mitigation efforts often fail to provide suitable aquatic habitat for vernal pool amphibians. We review the literature on pool creation in northeastern and central North America, highlighting how and why constructed pools often fail to support amphibian-related objectives. We recom-mend that practitioners consider the complex ecology of pool ecosystems and the historical and current distribution of pools and other wetlands in their local context before designing pool mitigation projects. Using vernal pool creation as a mitigation option should be a last resort (i.e., when elimination of natural pools is unavoidable). Monitoring should be target-specific and conducted for at least 5 years. Topographic, geologic, and other local factors affecting pool hydrology and ecology vary regionally; pool creation remains an imperfect science that will only advance by documenting failures and successes. We recommend an adaptive management approach to vernal pool creation in which the effectiveness of techniques is evaluated and refined based on research.
A detailed redescription of Chirocephalus tauricus Pesta, 1921 is provided, and two new fairy shrimp taxa belonging to the “diaphanus” and “bairdi” groups (Brtek, 1995), Chirocephalus algidus sp. nov. and C. brteki sp. nov., are described and discussed. The new species were collected in Turkey, respectively from Alagöl, a temporary pool close to the glacial Lake Karagöl on Mount Bolkar, Taurus, 3100 m a.s.l. (border of Nigde province), and from Lake Alan Gölü, 600 m a.s.l., a shallow lake on the border of Izmir province, close to the village of Bozalan. A number of morphological features (related to the first antenna, mandibles, first maxilla and some notopods) are also illustrated and discussed in relation to their taxonomic and phylogenetic importance.
Small natural features (SNFs), landscape elements that influence species persistence and ecological functioning on a much larger scale than one would expect from their size, can also offer a greater rate of return on conservation investment compared to that of larger natural features or more broad-based conservation. However, their size and perceived lack of significance also makes them more vulnerable to threats and destruction. We examine the management of SNFs and conservation of the associated ecosystem services they generate from an economics perspective. Using the economic concept of market failure, we identify three key themes that explain prevailing threats to SNFs and characterize impediments to and opportunities for SNF management: (1) the degree to which benefits derived from the feature spillover, beyond the feature itself (spatially and temporally); (2) the availability and quality of information about the feature and those who most directly influence its management; and (3) the existence and enforcement of property rights and legal standing of the feature. We argue that the efficacy of alternative SNF management approaches is highly case dependent and relies on four key components: (1) the specific ecosystem services of interest; (2) the amount of redundancy of the SNF on the landscape and the level of connectivity required by the SNF in order to provide ecosystem services; (3) the particular market failures that need correcting and their scope and extent; and (4) the magnitude and distribution of management costs.
Temporary streams and rivers support biodiversity and provide valuable goods and services, especially in arid and semi-arid landscapes. However, temporary streams and rivers are being degraded at alarming rates owing to development, hydromorphological alteration, and disposal of waste water, among other stressors, and pressure will likely increase under global change. Here we propose that it is key to manage temporary streams and rivers as a unique ecohydrological type and not as a permanent waterway or a terrestrial ecosystem. Nevertheless, two challenges hinder this goal. First, data availability on intermittent low regimes and associated biotas is currently scarce. As a consequence, flow-ecology relationships in temporary waterways are largely unknown, and appropriate metrics to define and monitor their ecological status are missing. Second, the ecological and social values of temporary streams and rivers are often underestimated, being regarded as secondary ecosystems relative to permanent waterways. To conserve temporary streams and rivers, ecologists need to define them as unique ecosystems and conservation targets, and practitioners need to systematically collect biological and hydrological data in these ecosystems. Innovative approaches at the intersection of ecology, citizen science, and management, can also contribute to their management and conservation by: i) mapping them, ii) informing people about their ecological values, iii) safeguarding them from further human threats, iv) preserving their flow regime when managing reservoirs, wastewater treatment plants, and water abstraction activities, and v) restoring physically-degraded temporary reaches (e.g. due to gravel mining and off-road use) or reaches that have lost historical flows due to increasing drought severity, diversions, and groundwater overuse.
Rocky outcrops are geological features that encompass a wide variety of physical environments, including escarp-ments, overhangs, cliffs, tors, boulder-heaps and insular domes (inselbergs). They support high levels of species diversity and endemism, and provide stable micro-climates for thousands of years. They provide critical breeding sites for many top order mammalian and avian predators; nesting sites for colonial species such as seabirds, bats and swifts and ecological refuges for ancient lineages. Rock overhangs and caves also provide important insights into our ecological past where they contain the remains of extinct species. Because rocky environments are generally less fertile, steep-sided and less accessible than the surrounding landscape, they are typically less prone to human disturbances. Nonetheless, many rocky outcrops, particularly in commodity production landscapes, face a variety of threats including soil compaction and erosion caused by livestock; nutrient enrichment and weed invasion ; introduced predators; and physical damage caused by recreational and quarrying activities. Even rocky outcrops in seemingly pristine environments may be affected by altered fire regimes, air pollution (including acid rain) and potentially climate change. In agricultural landscapes, various approaches have been taken to conserve rocky outcrops, including land acquisition for conservation, fencing from livestock and private land conservation agreements with landholders. In more intact landscapes, targeted actions to conserve rock-dwelling fauna include limiting human access to critical breeding sites, baiting to reduce pressure from introduced predators, restoring rock microhabitat and translocation of endangered species. Future management actions will need to involve better inventory of the biophysical attributes and fine-scale mapping to improve the awareness of these small natural features.
In this chapter, we perform a comparison of the invertebrate assemblages of the 15 wetland types included in the book using nine faunal groups (mollusks, leeches, large branchiopods, malacostracans, odonates, the so-called EPT taxa (Ephemeroptera, Plecoptera, Trichoptera), hemipterans, coleopterans, and dipterans). Family level was used in order to avoid some biogeographic biases and because it is the lowest taxon that was reliably reported by authors across all habitats. Tables comparing assemblage composition of each wetland type were provided for each fauna group. Richness patterns of the nine analyzed taxonomic groups clearly distinguished between high- and low-richness wetland types. Additionally, we proposed some conceptual models in order to explain how the Pool of Taxa available to colonize specific wetland types are determined by biogeography, climate, and habitat history, and how environmental factors operate filter the taxa present in a wetland type (i.e., hydroregime, wetland size, predation, etc.).
Ecological relationships and processes vary across species’ geographic distributions, life stages and spatial, and temporal scales. Montane landscapes are characterized by low wetland densities, rugged topographies, and cold climates. Consequently, aquatic-dependent and low-vagility ectothermic species (e.g., pool-breeding amphibians) may exhibit unique ecological associations in montane landscapes. We evaluated the relative importance of breeding- and landscape-scale features associated with spotted salamander (Ambystoma maculatum) and wood frog (Lithobates sylvaticus) wetland occupancy in Maine's Upper Montane-Alpine Zone ecoregion, and we determined whether models performed better when the inclusive landscape-scale covariates were estimated with topography-weighted or circular buffers. We surveyed 135 potential breeding sites during May 2013–June 2014 and evaluated environmental relationships with multi-season implicit dynamics occupancy models. Breeding site occupancy by both species was influenced solely by breeding-scale habitat features. Spotted salamander occupancy probabilities increased with previous or current beaver (Castor canadensis) presence, and models generally were better supported when the inclusive landscape-scale covariates were estimated with topography-weighted rather than circular buffers. Wood frog occupancy probabilities increased with site area and percent shallows, but neither buffer type was better supported than the other. Model rank order and support varied between buffer types, but model inferences did not. Our results suggest pool-breeding amphibian conservation in montane Maine include measures to maintain beaver populations and large wetlands with proportionally large areas of shallows ≤1-m deep. Inconsistencies between our study and previous studies substantiate the value of region-specific research for augmenting species’ conservation management plans and suggest the application of out-of-region inferences may promote ineffective conservation.