No full-text available
To read the full-text of this research,
you can request a copy directly from the author.
Biodiversity and Ecosystem Function: The Debate Deepens
Abstract
One of the tenets of the conservation movement has been that areas containing many species--those of high biodiversity--are
particularly worth saving, since ecosystems of high diversity show improved ecosystem function. As Grime explains in his Perspective,
this tenet is being replaced by another view, which is bolstered by three reports in this week's issue (pages
1296,
1300, and
1302). These studies all show that it is actually the specific features of the species in an ecosystem that determine its function--not
their number.
... The predicted three C-S-R strategies of Grime (1977) further provided basis for the functional approach related to aquatic macrophyte, namely Competitive (C), Stress-tolerant (S), and Ruderal (R) strategy that were complemented with a fourth strategy by Kautsky (1988). The fourth strategy came out of the division of the stress-tolerant into two types namely stunted (S) and biomass-storer (B) ( Fig. 1) according to high or low disturbance, respectively (Kautsky, 1988;Arthaud et al., 2012). ...
... The functional approach for stream periphyton started with construction of functional groups based on the history strategies of competitors, stress tolerators, and ruderals (C-S-R) of Grime (1977). From these, four groups were assembled namely competitive taxa, competitive-stress-tolerant, stress-tolerant, and ruderal (Fig. 1). ...
... Research on the functional ecology on phytoplankton has followed a similar approach as has been done on terrestrial plants: i.e., competitors (C), stress tolerators (S), and ruderals (R) (Grime, 1977). Using this principle, Reynolds (1984) separated pelagic algae based on the strategies of C-invasive, S-acquisitive, R-attuning species. ...
In this review we provide an overview of functional traits for freshwater communities, includ- ing macrophytes, periphyton, phytoplankton, fish, macroinvertebrates, and more thoroughly testate amoebae, rotifers, cladocerans, and copepods. Our approach provides a synopsis of functional traits of these groups, which is emerging as a valuable tool in evaluating environmental changes and anthropogenic influences. For the zooplankton community gather- ing information on traits remains a work in progress. Employing a standardized schema when selecting functional traits across zooplankton groups is a non- optional task; this is especially the case for rotifers because to their diversity of forms and feeding strate- gies. The role of microcrustaceans in trophic chains has highlighted importance of traits for this group, thus providing clues to their ecosystem effects. Here we aim at providing a framework for functional trait selection in aquatic communities prioritizing life strategies in resources acquisition, habitat preference, and life span and reproduction. Notwithstanding, the assembly of a framework of traits remains in pro- gress and with it, is the taking shape of multiple and varying functions and services that the diverse com- munities are constantly providing within freshwater ecosystems.
... First, N addition directly weakens ecosystem stability (i.e., N enrichment directly affects mean biomass production and its interannual variability) (Isbell et al., 2013;Seabloom et al., 2021). Second, N addition weakens ecosystem stability through affecting biodiversity (species richness, phylogenetic diversity and dominance) (Cadotte et al., 2012;Grime, 1997;Hautier et al., 2014;Hautier et al., 2015). Third, N addition weakens ecosystem stability by directly decreasing species asynchrony (Hautier et al., 2014;Muraina et al., 2021), population stability (Song et al., 2019;Zhang et al., 2019) and dominant species stability (Grime, 1997;Ma et al., 2017;Polley et al., 2007;Song et al., 2019). ...
... Second, N addition weakens ecosystem stability through affecting biodiversity (species richness, phylogenetic diversity and dominance) (Cadotte et al., 2012;Grime, 1997;Hautier et al., 2014;Hautier et al., 2015). Third, N addition weakens ecosystem stability by directly decreasing species asynchrony (Hautier et al., 2014;Muraina et al., 2021), population stability (Song et al., 2019;Zhang et al., 2019) and dominant species stability (Grime, 1997;Ma et al., 2017;Polley et al., 2007;Song et al., 2019). Fourth, N addition indirectly reduces species asynchrony and population stability by changing biodiversity, which weakens ecosystem stability (Hautier et al., 2020;Muraina et al., 2021;Smith and Knapp, 2003;Zhang et al., 2019). ...
... Our study is a local study for a specific grassland ecosystem, likely making the implications limited. In addition, species richness might impact ecosystem stability through a way that we did not detect in the current study (Grime, 1997;Isbell et al., 2017), for example, by promoting and maintaining the structure diversification of ecosystem (Grime, 1997). ...
Increased nitrogen (N) deposition is known to reduce the ecosystem stability, while the underlying mechanisms are still controversial. We conducted an 8-year multi-level N addition experiment in a temperate semi-arid grassland to identify the mechanisms (biodiversity, species asynchrony, population stability and dominant species stability) driving the N-induced loss of temporal stability of aboveground net primary productivity (ANPP). We found that N addition decreased ecosystem, population, and dominant species stability; decreased species richness and phylogenetic diversity; increased species dominance; but had nonsignificant effects on community-wide species asynchrony. Structural equation model revealed that N-induced loss of ecosystem stability was mainly driven by the loss of dominant species stability and the reduction in population stability. Moreover, species relative instability was negatively related with species relative production and the slopes increase with N addition, indicating that N addition weakened the stabilizing effect of dominant species on ecosystem function. Overall, our results highlight that the dominant species control the temporal stability of ANPP in grassland ecosystem under N addition, and support ‘dominance management’ as an effective strategy for conserving ecosystem functioning in grassland under N deposition.
... Being interested in understanding nature as it is, Grime was highly critical of the new wave of biodiversity-ecosystem functioning experiments that started in the 1990s (Grime, 1997). As a consequence, we added to the main experiment a so-called dominance experiment where only nine dominant species were used as pool to form all monocultures, all two-species mixtures and more species-rich communities, with all species equally represented at all diversity levels. ...
... Since the mid-1990s there has been considerable effort, vigorously driven and supported by several 'establishment' ecologists, to demonstrate that plant species richness is one of the main drivers of ecosystem functioning. Grime took a different view and one that I have consistently shared (meaning that we, along with Michael Huston, unwittingly ended up together and on the same side of a somewhat polarizing debate in the late 1990s), which is that while species richness may indeed play a role in driving ecosystems, the effects of richness are inconsistent and often not large and are frequently overridden by other drivers, and that the importance of species richness as a major ecosystem driver was being heavily oversold (Grime, 1997;Huston et al., 2000;Wardle et al., 2000). Grime's biggest and longest lasting scientific contribution to this debate was his 'mass ratio' hypothesis (Grime, 1998), proposing that ecosystems should be driven primarily by the traits of the dominant species, and which provides a convincing and plausible reasoning as to why plant community composition rather than species richness may be a powerful driver of ecosystem functioning. ...
Perhaps as much as any other scientist in the 20th century, J.P. Grime transformed the study of plant ecology and helped shepherd the field toward international prominence as a nexus of ideas related to global environmental change. Editors at the Journal of Ecology asked a group of senior plant ecologists to comment on Grime's scientific legacy.
This commentary piece includes individual responses of 14 scientists from around the world attesting to Grime's foundational role in plant functional ecology, including his knack for sparking controversy, his unique approach to theory formulation involving clever experiments and standardized trait measurements of large numbers of species, and the continued impact of his work on ecological science and policy.
... High biodiversity is a term that is frequently used by authors of inventory studies wishing to stress the significance of their results (Grime, 1997). Authors are aware that the more "biodiverse" a locality appears, the greater its perceived contribution to global biodiversity, and consequently the greater the likelihood that it will receive attention from conservation-planners (Grime, 1997). ...
... High biodiversity is a term that is frequently used by authors of inventory studies wishing to stress the significance of their results (Grime, 1997). Authors are aware that the more "biodiverse" a locality appears, the greater its perceived contribution to global biodiversity, and consequently the greater the likelihood that it will receive attention from conservation-planners (Grime, 1997). However the employment of the term "high biodiversity" and the more hyperbolic "mega-diversity", whilst understood as concepts even by non-specialists, does not follow any formal guidelines (Kaennel, 1998), even though it can greatly influence decision-makers, many of whom may lack formal biological training of their own. ...
Global conservation resources are limited and as a result donors and funders are forced to make difficult decisions as to which areas are in most urgent need of support. Biodiversity can play a key role in these choices, but many other factors must be considered. In order to assist with such decisions we present a simple index that can be employed by non-scientists in poorly sampled countries, using the reptile fauna of 55 protected and two unprotected areas of Paraguay as a case study. This index can be applied at multiple taxonomic and geographic levels to minimize biases generated by uneven sampling. We offer words of caution on unsupported claims of high biodiversity, and highlight how the use of inaccurate terminology, although well-intentioned, can be detrimental to national or local conservation efforts. Results show that the top two areas of conservation priority in Paraguay are currently unprotected, and current investment of resources is ineffective and insufficient for long term protection of Paraguay’s globally and nationally threatened reptiles.
... In the case of yellow rattle, negative biodiversity-productivity relationships are likely rooted in species identity effects (e.g. shifts in mean trait values), which can confound the positive impact of biodiversity gains (Grime, 1997). Yellow rattle is a hemi-parasitic plant with a wide host range, but with a preference for targeting grass species (Jiang et al., 2010;Westbury, 2004). ...
Cost‐effective strategies to increase biodiversity are a fundamental requirement to reconcile conservation and food production in agricultural landscapes. Key for the implementation of such strategies is an accurate quantification of both their benefits and potential associated trade‐offs.
We therefore assessed, in a commercially managed grassland, biodiversity responses to two low‐cost management interventions and their mediating effects on ecosystem services.
In a 6‐year experiment, we showed that a one‐time seed bank activation treatment had strong initial impacts on biodiversity, increasing plant richness in year 1 by 61%. Long‐term effects, which were also driven by the second management intervention, the propagation of the keystone species yellow rattle, were weaker but nonetheless substantial. These positive biodiversity responses improved ecosystem multifunctionality through additive positive effects of richness, evenness and phylogenetic distinctiveness on nectar production and structural habitat complexity.
In contrast, hay biomass production was negatively affected by both management interventions, resulting in a multilevel trade‐off between biomass production competing with biodiversity conservation and the provisioning of other ecosystem services.
Synthesis and applications . In this study, we demonstrate that the maximisation of either biodiversity or biomass production requires largely different land management practices. The evaluation of this trade‐off, however, is strongly dependent on its social, economic and ecological context and requires clearly defined land management priorities for both food production and biodiversity conservation.
... Some prior studies focused on plant communities have similarly found ecosystem functioning to be incorrectly attributed to plant α diversity when other characteristics of plant communities (e.g., biomass, functional groups) were omitted from analyses [64,65]. Indeed, a recent analysis demonstrated that plant diversityecosystem function relationships are noncausal associations and that ecosystem functions are instead driven by functional traits of the resident species [66]. ...
Ecosystem functions and services are under threat from anthropogenic global change at a planetary scale. Microorganisms are the dominant drivers of nearly all ecosystem functions and therefore ecosystem-scale responses are dependent on responses of resident microbial communities. However, the specific characteristics of microbial communities that contribute to ecosystem stability under anthropogenic stress are unknown. We evaluated bacterial drivers of ecosystem stability by generating wide experimental gradients of bacterial diversity in soils, applying stress to the soils, and measuring responses of several microbial-mediated ecosystem processes, including C and N cycling rates and soil enzyme activities. Some processes (e.g., C mineralization) exhibited positive correlations with bacterial diversity and losses of diversity resulted in reduced stability of nearly all processes. However, comprehensive evaluation of all potential bacterial drivers of the processes revealed that bacterial α diversity per se was never among the most important predictors of ecosystem functions. Instead, key predictors included total microbial biomass, 16S gene abundance, bacterial ASV membership, and abundances of specific prokaryotic taxa and functional groups (e.g., nitrifying taxa). These results suggest that bacterial α diversity may be a useful indicator of soil ecosystem function and stability, but that other characteristics of bacterial communities are stronger statistical predictors of ecosystem function and better reflect the biological mechanisms by which microbial communities influence ecosystems. Overall, our results provide insight into the role of microorganisms in supporting ecosystem function and stability by identifying specific characteristics of bacterial communities that are critical for understanding and predicting ecosystem responses to global change.
... Our results for naturally occurring freshwater mussel assemblages show some similarities and differences with smallscale BEF experiments and observations from other natural systems. Similar to BEF experiments, we found that random loss of species and species identity both can have strong effects on ecosystem functions contributed by assemblages of mussels, although interpretation of these effects in experimental settings remains contentious (Grime 1997, Huston 1997, Wardle et al. 2000, Loreau et al. 2001. Our data reflect the distribution of species biomass in natural systems, which buffered the effects of random species loss on standing-stock biomass and N-recycling in different ways. ...
Positive biodiversity–ecosystem functioning (BEF) relationships observed in experiments can be challenging to identify in natural communities. Freshwater animal communities are disproportionately harmed by global change that results in accelerated species loss. Understanding how animal-mediated ecosystems functions may change as a result of global change can help determine whether biodiversity or species-specific conservation will be effective at maintaining function. Unionid mussels represent half of imperiled species in freshwater ecosystems globally and perform important ecological functions such as water filtration and nutrient recycling. We explored BEF relationships for 22 naturally assembled mussel aggregations spanning three river basins. We used the Price equation to partition the contributions of species richness, composition, and context dependent interactions to two functions of interests: spatially-explicit standing-stock biomass (indirect proxy for function) and species-specific nitrogen (N) excretion rates (direct measure of N recycling). Random and non-random species loss each reduced biomass and N recycling. Many rare species with low contributions to biomass contributed to standing-stock biomass in all basins. Widespread species had variable function across sites, such that context dependent effects (CDEs) outweighed richness effects on standing-stock biomass in two basins, and were similar to richness effects in the third. Richness effects outweighed CDEs for N recycling. Thus, many species contributed a low proportion to overall N-recycling; a product we attribute to the high evenness and functional effect trait diversity associated with these communities. The loss of low-functioning species reduced the function of persisting species. This novel result using observational data adds evidence that positive species interactions, such as interspecific facilitation, may be a mechanism by which biodiversity enhances ecosystem functions. Our work stresses the importance of evaluating species-specific contributions to functions in diverse systems, such as nutrient cycling when maintaining specific animal-mediated functions is a management goal because indirect proxies may not completely characterize BEF relationships.
... Moreover, this aspect is extensively integrated into the monitoring programs due to the long-term variations of the sludges, caused by the implementation and modification of treatments in the sewage plants (Calabretta et al., 2008). Since the ecosystem processes are influenced by the functional characteristics of the organisms, rather than by taxonomic identity (Grime, 1997), the use of structural features of macrofaunal communities alone might give misleading information regarding the function performed by macrofaunal communities that sustain an ecological system (Díaz and Cabido, 2001). Therefore, the monitoring program, in the framework of ecosystem-based management needs to balance the expected outcomes due to various anthropogenic activities and requires metrics, indices, and systematic methods able to assess the variation of ecosystem functioning due to anthropogenic contaminations (Mangano et al., 2017). ...
Sewage discharges represent a very common source of anthropogenic impact in coastal areas, contributing to generate a high intake of organic matter with consequent reduction of oxygen in the water column and sediments. Among the coastal benthic communities, macrofaunal community is widely involved in the main ecological processes, therefore environmental alterations that threaten these communities, affect their stability over time, and consequently their resistance and resilience.
The main objective of this Ph.D. project was to evaluate both on a spatial and temporal scale, structural, functional, and trophic variations of the coastal macrofaunal community, influenced by the sewage discharge of urban and domestic wastewater in the Gulf of Trieste (North Adriatic Sea). The sampled macrofauna was investigated through new analytical approaches that can best highlight the community response with all its characteristics as well as its change towards a functioning evaluation of the target ecosystem. In general, the community was characterized by high biodiversity values in conjunction with the presence of stress-tolerant species which suggested that the communities are subject to a moderate level of stress. Through the functional traits analysis, the expression of traits related to semi-continuous reproduction, sediment transporters, and sub-surface depositories were increased by moving from the most distant stations to those closest to the main discharge pipeline, suggesting the presence of a continuous wastewater supply. On the contrary, in the more distant stations, a greater expression of the suspension feeder was observed, indicating the presence of lower inputs of organic matter. However, from the analysis of functional richness and β-diversity emerged that following improvement of the plant, which took place over the years studied, the community responded with an increase in the number of species, particularly in the stations near the sewage discharge loading. Furthermore, the bioturbation and bio-irrigation potential were not directly connected with the variation of allochthonous substance but rather with the granulometric characteristics of the area. On the contrary, macrofaunal secondary production also seems to have been influenced by the presence of sewage discharge. High values of the P/B̅ ratio were calculated at the stations furthest from the sewage pipelines and a negative relationship was observed between biomass and trophic efficiency (TE) values. Therefore, it appears that sewage discharge induces an increase in TE at stations close to the pipelines. In our case, the sewage discharge has determined the presence of tolerant species with small size, low biomass, high reproduction, and growth rate, which seem to have allowed a greater transfer efficiency of energy at higher trophic levels.
Overall, community analyses both on a spatial and temporal scale have shown a good degree of resilience to environmental variations induced by the pronounced contribution of organic matter, as well as different patterns of organic matter use in terms of secondary production, productivity, and TE. These aspects (P, P/B̅ and TE) were also treated for the first time in the context of macrozoobenthic communities subject to the influence of sewage and organic enrichment.
The variety of methods applied suggest how the use of integrated approaches that consider macrofaunal communities, analyzing them both from a structural and functional-trophic point of view, can provide useful tools to better understand, monitor and evaluate the functioning of coastal ecosystems, including to multiple disturbing factors.
... More precisely, stress is defined by chemical or physical constraints that negatively affect plant growth and community productivity, such as cold temperature, and low light, water and nutrients availability, whereas, disturbance is defined as any biotic or physical constraint (e.g. grazing, burning, flooding) that destroys plant biomass (Grime , 1997. noted that nutrient-poor ecosystems that do not show other kinds of stress (like heathlands on sandy soils in temperate regions) can accumulate a high amount of biomass with time in case of low disturbance. ...
The interactions between plants along environmental gradients are not only the results of how plants affect their neighbours and how their neighbours respond to these effects, but also of how plants respond to environmental stresses. Related studies either involve different species or different ecotypes, which are populations of a species growing in different environments with specific adaptations. In this thesis, our main objective was to assess how both plant stress-tolerance and plant competitive and facilitative abilities drive plant-plant interactions along different stress gradients. First, we investigated the relationship between plant stress-tolerance and plant competitive and response abilities in a context where competitive interactions dominate: along a water gradient driven by differences in water availability between calcareous and siliceous substrates in the Gironde department (South-Western France). Then, the relationship between plant stress-tolerance and plant facilitative effect and response abilities was explored in a context where facilitative interactions dominate: in sites polluted by large amounts of heavy-metals in soils in the Pyrenees mountains (South France), along metal pollution gradients. We conducted experimental approaches (reciprocal transplant experiments and common garden experiments) at the interspecific and intraspecific levels. We also calculated appropriate indices to quantify the relative contributions of environmental stress and biotic interactions in determining the outcome of plant-plant interactions in both systems. Our results demonstrated a trade-off between stress tolerance and competitive effect and response abilities along the water gradient. Drought-tolerant species were better able to withstand stress, while stress-intolerant species were better able to withstand competition. Additionally, competitive effects were higher in plant communities dominated by stress- intolerant competitive species. A trade-off between stress tolerance and facilitative response abilities was also found in metal-polluted sites, as the less metal-tolerant species and ecotypes were more facilitated than the more metal-tolerant species and ecotypes. In contrast, we found a positive correlation instead of a functional trade-off between stress tolerance and plant facilitative abilities, since the most stress-tolerant ecotypes had greater facilitative effects on neighbouring species than the less stress-tolerant ecotypes. Finally, with respect to the indices used, we found that environmental stresses had a greater influence in determining the outcome of plant-plant interactions than the competitive effect of neighbours along the water gradient and a greater influence than the facilitative effect of neighbours at the highest pollution level.
... Seed parasitism (while still inside the vines) was higher for the latter. Imminent loss of biological diversity and the risk of the acceleration of this loss, brings out the need to objectively evaluate the role of biodiversity in ecosystem function, productivity and stability (Aizen and Feisinger 1994;Didham et al. 1996;Grime 1997). The effect of biodiversity in ecosystem viability requires sophisticated equipment, perhaps as a result of this it is only being considered in few studies (Richardson and Cowling 1993;Hooper and Vitousek 1997;Tilman et al. 1997). ...
The general objective of this Symposium was to build on the best science and technology available to assure that the data and information produced in future inventory and monitoring programs are comparable, quality assured, available, and adequate for their intended purposes, thereby providing a reliable framework for characterization, assessment, and management of forest ecosystems in North America. Central to the syntheses delivered in this Symposium was the conclusion that a fundamental improvement in the approaches used for inventorying and monitoring ecosystem resources is required to meet current and future environmental uncertainties. Specific actions were proposed to address these challenges. These strategic actions are described in the last chapter of these proceedings.
... A clonal species like Triglochin could concentrate N over a large area, translocating N between shoots and roots, creating long-lived nutrientenriched patches and contributing significantly to spatial variability in available N (Baye, 2007;Do, 2018). The differential ability of plant species to compete for nutrients within nutrientrich patches created by Triglochin could shift species abundances and increase diversity (Grime, 1997). As Triglochin shoots die back by mid-summer, they could decompose faster and release more nutrients than surrounding species because of their high N content (Quested et al., 2003). ...
Selectively planting native species could guide ecosystem development toward wetland restoration targets, once we understand how influential species function, alone and in combination. Knowing that Triglochin concinna (arrow grass, Juncaceae) accumulates N in its perennial roots, we asked how it would influence N dynamics on an excavated salt marsh plain at Tijuana Estuary, in southern California. We hypothesized that it would (a) accumulate N in roots and shoots, (b) reduce biomass of other marsh plain plants or, alternatively, (c) share N with neighbors as its litter decomposed and released N. We used 15N stable isotope enrichment to quantify N transfer between Triglochin and the marsh plain’s seven-species halophyte assemblage in field and greenhouse experiments. We also examined the effect of Triglochin on individual marsh plain species’ biomass and N accumulation. Triglochin had low shoot biomass (0.96 ± 0.5 g m−2 in field plots and 17.64 ± 2.2 g m−2 in greenhouse pots), high root:shoot ratios (4.3 in the field and 2.0 in the greenhouse), and high tissue N content (1.9 ± 0.2% in the field and 1.7 ± 0.1% in the greenhouse). Two productive perennials, Sarcocornia pacifica (pickleweed) and Frankenia salina (alkali heath), outgrew Triglochin; yet these biomass dominants produced 44%–45% less shoot biomass in greenhouse pots with Triglochin than without. However, we did not find this reduction in the field where roots were unconfined. In the greenhouse, δ15N values were higher for species grown with 15N-enriched Triglochin, indicating that this species made N available to its neighbors. The δ15N values for plants grown in the field exceeded background levels, also indicating that the marsh plain assemblage took up N released by Triglochin. We conclude that Triglochin can influence the restoration of salt marsh vegetation by accumulating N and releasing its tissue N to neighbors as leaves and roots decompose, while simultaneously reducing the biomass of neighbors. The seasonally deciduous Triglochin is low in shoot biomass, yet competitively superior in N uptake. Because this often-ignored species has limited tidal dispersal, we suggest restoration plantings, including tests of its ability to facilitate diversity where S. pacifica, the marsh plain dominant, might otherwise form monocultures.
... Efforts to determine the relationship between biodiversity and the stability o f ecological function are at the heart o f a long-standing debate in ecology (McCann 2000). While demonstration o f the diversity-stability link has been elusive (Grime 1997;Naeem 2002aNaeem , 2002b, mounting evidence supports the hypothesis that biodiversity loss could Sankaran and McNaughton 1999;Tilman 1996;Tilman and Downing 1994). Therefore, in this era o f rapid climate change, increasing natural resource exploitation, and accelerating species extinctions Smith et al. 1993;Vitousek et al. 1997 Northern forestry and carabids: the case for concern about old-growth species. ...
Boreal forests of Canada, and elsewhere, are increasingly stressed by multiple, potentially interacting disturbances. In addition to natural disturbances like wildfire, anthropogenic stressors associated with increasing demands for natural resources have become critical elements of the disturbance regime in many areas. Thus, biodiversity conservation and sustainable forest management will increasingly depend on our understanding of the cumulative ecological consequences of disturbance. I examined the combined effects of wildfire and industrial forestry practices on boreal mixed-wood ground beetles and saproxylic beetles, and on the ecological function of one saproxylic species. Ground beetle responses to the individual and combined effects of wildfire, forest harvesting and herbicide-use were species-specific, but disturbance combinations led to a greater decrease in the compositional variability of the entire ground beetle assemblage. For saproxylic beetle assemblages, the combination o f wildfire and forest harvesting (postfire salvage logging) reduced species richness and altered species composition to a greater extent that either disturbance alone. Postfire salvage logging also altered the trophic structure o f the saproxylic beetle assemblage and was particularly detrimental for wood- and bark boring species. Through a series of experiments, the abundance of one such species, Monochamus scutellatus scutellatus, was linked to decomposition processes in burned forests. Together, the results of these studies suggest that disturbance combinations should be avoided whenever possible because they may impact not only beetle diversity, but also decomposition processes in forests recovering from wildfire.
... The removal of species critical for an ecosystem leads to a loss of resilience, leading to an equilibrium shift in the ecosystem (Holling, 1986;Chapin et al., 1997;Grime, 1997;Tilman et al., 1997). Not much is known about the regulating services provided by the forage fish and most of their contribution is indirect via their predators. ...
The present paper is a review of the available literature on the significance of forage fish, the plethora of services they provide, and the threats faced by them. Forage fish are pelagic planktivorous species that operate as conduits of energy between the lower trophic level (plankton) and the upper trophic level (predators). A variety of ecosystem services are provided by them, from serving as prey for higher trophic levels to producing fish meal and oil. Forage fish have a consumption value for humans and cultural importance to many societies. Forage fish have faced constant natural and anthropogenic threats in the past, resulting in numerous fish collapses which subsequently impacted their predators. The economic benefit provided by forage fish has been estimated to be approximately $ 18.7 billion per annum. An introspection of the data on ecosystem services revealed lack of data on regulating and cultural services, eventually leading to a monetary underestimation and their commercial prioritization over the wider benefits they provide.
... Moreover, the idea of ecosystem ecology pioneers e.g. [8] that complexity ensures ecosystem stability has been questioned by a number of authors [9,10,11]. However, it is important to note that authors considering relationship between biodiversity and resilience predominantly focus on species diversity and often specifically on species richness [12]. ...
In the context of global environmental change ecosystem resilience becomes critical for long term survival of species and consistent delivery of ecosystem services. Concerns however exist on whether managing ecosystems for resilience would actually support biodiversity conservation. Current focus of empirical studies on species richness as the main measure of biodiversity may result in underestimation of the link between biodiversity and ecosystem resilience. A closer look at different levels of biodiversity, namely interspecific, intraspecific and ecosystem diversity allow better understanding of how biodiversity underpins resilience. Thus, a holistic approach to biodiversity research and management is needed to maintain ecosystem resilience in the context of global environmental change. All three level of biodiversity need to be considered. Landscape Approach is likely to be the most effective strategy in conservation, because preserving biodiversity at a landscape level is likely to simultaneously ensure metapopulation genetic diversity, secure high functional redundancy and response diversity, and preserve ecological memory, which ultimately ensure ecosystem resilience and consistent flow of ecosystem services.
... These community diversity met-rics share the goal of quantitatively describing the assortment of species found within a region. Much debate has surrounded the link between species diversity and ecosystem structure, function, stability, and resilience (Grime 1997, Schwartz et al. 2000, Loreau et al. 2001, Tilman et al. 2014. Despite these competing views, ecologists broadly agree there are benefits to increased diversity, but the degree of benefits conferred varies among ecosystems. ...
Essential fish habitat is critical for foraging, breeding, or as refugia. As such, restoration of these habitats has the potential to increase the diversity and abundance of fishes. Here, we explored how fish communities responded in the first 12-24 mo following oyster reef restoration. Study sites included 8 restored reefs plus 4 live and 4 dead reefs as controls. Oyster reef metrics (e.g. density, height, thickness) and fish abundance and diversity metrics were quantified, including species richness, Shannon diversity, Simpson’s diversity, and Pielou’s evenness. Species composition was explored further to identify indicator species and assess habitat preferences. Patterns of fish community diversity and species composition were compared to oyster reef metrics to discern what oyster reef characteristics best predict fish diversity. Results showed that intertidal oyster reefs were structurally restored and shifted from resembling negative control reefs to positive control reefs within 12-24 mo. Across all treatment types, oyster shell height and reef thickness were the best predictors of fish diversity. However, at the fish community level, assemblages at restored reefs were similar to those at positive and negative controls. Species-level analyses suggest treatment types have unique indicator species, including Chilomycterus schoepfi (striped burrfish) for dead reefs, Lutjanus synagris (lane snapper) for restored reefs, and Gobiosoma robustum (code goby) for live reefs. This work suggests fishes can be used as higher trophic level indicators of restoration success, and ecosystem-based approaches, such as habitat restoration, can restore essential fish habitat, thus benefiting fish communities while moving coastal ecosystems toward sustainability.
... For example, in early successional moist tropical forests, there is a high proportion of fast-growing species with low tissue density [6]. These pioneer species reach tall statures quickly, and their tissues are short-lived, decomposing quickly [7]. The abundance of such traits results in faster nutrient cycling and carbon capture, both important ecosystem services, although there is also faster carbon release [8][9][10]. ...
Tropical dry forests (TDFs) represent one of the most diverse and, at the same time, most threatened ecosystems on earth. Restoration of TDFs is thus crucial but is hindered by a limited understanding of the functional diversity (FD) of original communities. We examine the FD of TDFs based on wood (vessel diameter and wood density) and bark traits (total, inner, and outer bark thicknesses) measured on ~500 species from 24 plant communities and compare this diversity with that of seven other major vegetation types. Along with other seasonally dry sites, TDFs had the highest FD, as indicated by the widest ranges, highest variances, and largest trait hypervolumes. Warm temperatures and seasonal drought seem to drive diverse ecological strategies in these ecosystems, which include a continuum from deciduous species with low-density wood, thick bark, and wide vessels to evergreen species with high-density wood, thin bark, and narrow vessels. The very high FD of TDFs represents a challenge to restoring the likely widest trait ranges of any habitat on earth. Understanding this diversity is essential for monitoring successional changes in minimal intervention restoration and guiding species selection for resilient restoration plantings in the context of climate change.
... As a rule, the researchers now understand ecosystem services as the quite wide range of the forms of the use of the functions of ecosystem, based on the need of the society to use the natural resources in the sparing mode which will not lead the natural processes and the individual ecosystems to depletion [1][2][3][4]. Biodiversity has been and remains as one of the most difficult service which is amenable to research and forecasting. At the same time, the climatic changes influence on significantly both biodiversity as a whole, its individual components, and the welfare (well-being) of the person, which he receives on the basis of biodiversity [5,6]. ...
To estimate possible changes for some economical branches in South Ukraine which use the nature resources, three scenarios of climate changes were reviewed: increase of temperature and increase of precipitation; increase of temperature and decrease of precipitation; decrease of temperature and increase of precipitation. Impact on the Azov Sea ecosystems under these three scenarios was considered in respect of changes in salinity and temperature of water that consequently effects on ichthyofauna and fish industry. Trends of fish suffocation are also described. Agricultural risks induced by pests (on an example of the locust) under extreme high temperatures in a spring-summer season were discussed, with identification of possible distribution sites of the pest. The research carried out in the framework of the project “Building Capacity for a Black Sea Catchment Observation and Assessment System supporting Sustainable Development” (2009-2013) of the 7 th Framework Programme
... Initial research claimed to demonstrate benefits to ecosystem function from higher biodiversity (Naeem et al., 1994;Tilman and Downing 1994;Tilman et al., 1997). However, there is a growing body of experimental evidence that the functional characteristics of component species are at least as important as the number of species per se for maintaining critical ecosystem processes (Grime, 1997;Wardle et al., 1997;Bardgett and Shine, 1999). However, it is not known how much biodiversity is needed to ensure continuance of specific soil functions. ...
... Reducing biological invasions in forests requires knowledge of how forest management practices such as linked-press stress/disturbances and compounded pulse disturbances influence plant diversity. In this paper, 'stress' refers to external abiotic constrains (e.g., soil moisture or fertility) not caused by the vegetation itself, that limit biomass production (Grime, 2006) and 'disturbance' refers to a natural or land use related event that removes biomass or individuals (Grime, 1977(Grime, , 2006. A 'linked-press' stress/disturbance is when a stress or disturbance is a casual factor in the occurrence or attributes of a subsequent disturbance (Simard et al., 2011, Burton et al., 2020, and a 'compounded pulse' disturbance refers to "multiple disturbance events that occur without sufficient time for ecosystem recovery between them" (Paine et al., 1998, Burton et al., 2020. ...
Although exotic (i.e., non-native) plant species are among the main factors contributing to ecosystem change globally, investigations of northern temperate and boreal forest ecosystems in North America in the context of invasion science are scarce. Multiple hypotheses, including the ‘biotic resistance’, ‘intermediate disturbance’ and ‘disturbance-mediated’ hypotheses, can serve as a framework to assess invasibility. Here we used the NEBIE (natural disturbances and extensive, basic, intensive, and elite silviculture intensities) plot network, consisting of field sites across different forest types that originated from a range of silviculture systems to assess the role of silviculture intensity on exotic plant diversity. Botanical surveys were conducted pre- and two-, five-, and ten years post-forest harvesting. Thirty exotic plant species were observed across all studied forests, of which 20 belonged to the Asteraceae, Fabaceae, and Poaceae families. Exotic species richness was highly correlated with native species richness and peaked as a result of intermediate linked-press (i.e., climate, soils, historic disturbance regimes, and silviculture systems) stresses/disturbances and compounded pulse (i.e., harvest intensity, site preparation, and herbicide use) disturbances for all post-harvesting measurement years. Observed exotic species are considered to have traits consistent with those of ruderal species. In this context, our results support the intermediate disturbance and disturbance-mediated hypotheses, but not the biotic resistance hypothesis. To reduce the richness of exotic plant species in northern temperate and boreal forests we recommend minimizing the use of intermediate compounded pulse disturbances.
... Plant species diversity is known to have positive effects on ecosystem functioning. In particular, a lot of studies highlighted a positive effect of species diversity on productivity (Tilman et al. 1996;Hooper and Vitousek 1997;Yachi and Loreau 1999;Hector et al. 1999) with evidence that functional group richness, and further, functional dissimilarity between groups (Heemsbergen et al. 2004), play a greater role than species richness per se (Grime 1997;Balvanera et al. 2006). The mechanisms that could explain a positive diversity-productivity relationship are often grouped under two main categories of effects: "complementarity effects" (i.e. ...
In agriculture, the plants and animals that are bred come from long-term artificial selection procedures that aim at producing individuals with desirable traits. Such procedures can be applied at levels of biological organization higher than the individual such as the community level, which is of particular interest in the field of microbial community engineering. Indeed, microbial communities play key roles in agriculture but also in the environment, health and industry, and a growing body of literature shows promising results regarding the artificial selection of microbial communities for desirable functions. However, for artificial selection procedures at the community level to be efficient, there is a need for improvements of the process, which will be achieved by a better understanding of community functioning and evolution. The aim of this work was to identify the ways of improving the artificial selection of microbial communities through a better understanding of the consequences of considering communities as selection units and to shed light on the knowledge that it could bring to our understanding of community ecology and evolution. In a first experiment, we applied an artificial selection procedure on a soil microbial community and showed that the reproduction step, i.e. the way offspring communities are created from parental ones, can be a key determinant of the outcome of the artificial selection as it can influence community structure and diversity. Pooling several parental communities seemed to be suitable to increase the level of a function under selection. In a second experiment, we applied an artificial selection procedure on synthetic bacterial communities varying for their initial specific richness level. We showed that community diversity positively influenced the level of the function under selection and also affected community evolutionary dynamics. We also had evidence that it could affect the efficiency of the artificial selection, but the relationship was not linear, and we evidenced a trade-off between increasing community richness and preserving between-community dissimilarity in composition. This trade-off could limit the positive effect of an increase in richness on artificial selection efficiency. In a third experiment, we assessed whether the pairwise interspecific interactions evolved during the experimental evolution of bacterial communities. Our results indicated that the evolution of the interspecific interactions was widespread in community evolution as it was detected in 50% of the studied communities. Moreover, even in the communities in which the interactions did not evolve themselves, we showed that they influenced the evolutionary responses of the strains and communities which was both abiotic environment- and community-dependent. All together these results highlighted the close links between community ecology and evolution and gave several avenues for improving artificial selection: choosing the reproduction method according to the desired direction of change in a function, promoting community diversity, promoting the evolution of the interspecific interactions. Improving our understanding of community eco-evolutionary dynamics will open the way to an efficient artificial selection of communities and its use as a tool for microbial community engineering.
... In the other hands, current losses in biodiversity by human-induced environmental changes has renewed interest in research on the significance of biodiversity for ecosystem functioning and resilience with respect to stress and disturbance (Chapin et al., 1997). Grime (1997) concludes that there is currently no convincing evidence that ecosystem processes are crucially dependent on higher biodiversity. Rather, the functional characteristics of the prevalent plant species would be important in monitoring ecosystem processes. ...
Considerable attention has been paid to climate change and its impacts on biodiversity. The climate change has caused several problems such as continuous ecosystem degradation and a resultant biodiversity decline. In addition, climate warming has a range of indirect effects through changes in vegetation type level and sea that affect physical and biological systems. This has also led to changes in the distribution of species, as well as reductions in the size of populations, or even local extinctions of these populations. Moreover, many species are disappearing with time due to climate change combined with the emergence of disease that develops and increases with time. These problems affect different biodiversity components that are close to collapse. This chapter explored the richness of biodiversity in arid and semi-arid zones. It is also illuminates the effects of climate change on distribution of biodiversity. The authors highlight the responses of biodiversity under climate change, in terms of species extinction, biodiversity loss, and the impacts of climate change to ecological tourism. Finally, the authors show how biodiversity can overcome the effect of climate change, by developing some systems that allow to them to survive and conservation of species and ecosystems.
... Identifying social resilience in colonies is essential for honeybee health and preventing collapse. Theory predicts that there is a trade-off between the ability to recover, i.e. fast growth under benign conditions, and the ability to resist or tolerate stress ( Pianka, 1970 ;Grime, 1997 ). Current studies are far from understanding these trade-offs in honeybee colonies. ...
Honeybee colonies experience high losses, induced by several stressors that can result in the collapse of colonies. Experiments show what effects stressors, such as parasites, pathogens and pesticides, can have on individual honeybees as well as colonies. Although individuals may die, colonies do not always collapse from such disturbances. As a superorganism, the colony can maintain or return back to homeostasis through colony mechanisms. This capacity is defined as social resilience. When the colony faces a high stress load, this may lead to breakdown in mechanisms, loss in resilience and eventually colony collapse. Before social resilience can be measured in honeybees, we need to examine the mechanisms in colonies that allow recovery and maintenance after stressor exposure. Here, we discuss some of these mechanisms and how they affect the social resilience of honeybee colonies. Understanding social resilience in honeybees is essential to managing colony health and loss prevention.
... Moreover, this aspect is extensively integrated into the monitoring programs due to the long-term variations of the sludge caused by the implementation and modification of treatments in the sewage plants (Calabretta and Oviatt, 2008). Since the ecosystem processes are influenced by the functional characteristics of the organisms, rather than by taxonomic identity (Grime, 1997), the use of structural features of macrofaunal communities alone might provide misleading information regarding the function performed by macrofaunal communities that sustain an ecological system (Díaz and Cabido, 2001). Therefore, in the framework of the monitoring programs, the ecosystem-based management needs to balance the expected outcomes due to various anthropogenic activities and requires metrics, indices, and systematic methods able to assess the variation of ecosystem functioning due to anthropogenic impacts (Mangano et al., 2017). ...
We assessed the effect of sewage-derived materials on the structural and functional attributes of the soft-bottom macrofauna at an increasing distance from the entire diffusion area. Our results showed clear spatial changes of macrofaunal density and biomass along the distance gradient from the main outfall. High values of biodiversity, species composition, and species linked to organic enrichment near the duct suggested that moderate organic stress affected this community. The traits analysis abundance-based, compared to biomass-based one, distinguished most clearly sewage contamination conditions. Functional diversity displayed spatial patterns with higher values in the less impacted sites and was significantly related to species numbers and the biotic indices (like M-AMBI). This approach is ideal for detecting macrofaunal functional changes due to sewage contamination. Thus, we infer that traits analyses could offer great potential for environmental assessment and monitoring of coastal areas influenced by human activities.
... Moreover, all measures of taxonomic diversity were excluded from the final models, suggesting no significant contributions of taxonomic diversity to the variations of AGB. Although most empirical studies have documented a positive effect of species richness and diversity on ecosystem functions (Grime, 1997;Loreau et al., 2001;Mori et al., 2017;Thompson et al., 2018;Tilman et al., 2014), a pronounced role of functional composition irrespective of taxonomic diversity was also observed in the natural wetland plant community of Poyang Lake (Fu et al., 2018). As the species composition might have potential links to AGB via its correlation with traits diversity, the insensitive ecosystem functions to taxonomic diversity might reflect that most wetland plant species have similar traits and thus are functionally redundant in a given community (Fu et al., 2021). ...
Human activities markedly modify diversity patterns of plant communities and their response to environmental conditions, with subsequent consequences for ecosystem functions. We measured 11 key functional traits of 47 plant species and assessed both taxonomic and functional composition as well as above‐ground biomass (AGB) of plant communities from 127 plots in the Lake Dongting wetland. Using a generalized multilevel path model, we examined the cascading effects of hydrological gradients on plant diversity and ecosystem functions in two distinct habitat types (short grassland with a natural community dominated by Carex spp. and tall grassland with a managed artificial community dominated by Triarrhena lutarioriparia and Phragmites australis). We found significant differences in the response of plant diversity and AGB to hydrological gradients. Species richness, Shannon‐Wiener diversity, multiple‐trait functional diversity measures (i.e., functional richness, functional dispersion, Rao’s quadratic entropy) and community‐weighted mean (CWM) of shoot height were all significantly higher and functional divergence and CWM of tuber significantly lower in tall grassland. AGB was significantly higher in short grassland, largely driven by variations of functional diversity rather than of taxonomic diversity. Moreover, we found a significant cascading effect of elevation and soil moisture on AGB, directly or indirectly induced by changes in functional diversity in the short grassland, while only direct effects of elevation on AGB were observed in the tall grassland. Therefore, our study provides strong evidence that human‐induced changes in habitat types uncoupled the cascading effects of hydrological gradients on ecosystem functions mediated by either the taxonomic or the functional diversity.
... Several studies proved that ecosystem processes are mainly determined by functions of organisms rather than populations (Leps et al., 1982). For example, the differences in the response of five adjacent grasslands in northern England to frost, drought and fire can be predicted from the functional characteristics of the dominant vegetation, unrelated to the population of vegetation (Grime, 1997;MacGillivray and Grime, 1995;Schwartz et al., 2000). It indicated a biodiversity conservation project solely based on species richness rather than comprehensive consideration of the entire evolution of species would fail to identify the most crucial habitats for the conservation of species genetic information (Smith et al., 1993). ...
Although the knowledge and understanding of biodiversity is rapidly increasing, very little of the total biodiversity is currently considered in applied conservation actions. In this sense, it is crucial to integrate independent fields of biodiversity models and perspectives with conservation issues, in particular, the views that address the links between biodiversity, ecosystem services and human well-being, species interaction, and focal charismatic species. This study overcomes the lack of framework necessary for this integration, and proposes three perspectives and approaches to assess biodiversity. The first perspective is biodiversity potential. It considers the correlation between renewable resources in local ecosystems and biodiversity potential, in terms of the possibility of maintaining a high degree of biodiversity. The energy cost is evaluated using both static and dynamic methods, based on the measure of the emergy of local renewable resources and of the total emergy throughput needed by components in ecosystem food webs, respectively, also highlighting the link between biodiversity and ecosystem services, species interactions via energy transfer respectively. The second perspective considers the contribution of biodiversity to human well-being, such as domestication. In this approach, we assess the contribution of biodiversity to humans by calculating the emergy of non-renewable resources required to domesticate animals or plants into agricultural products. The third perspective highlights the significance of local focal charismatic species to global biodiversity conservation. Taking rare species as an example, the emergy required to maintain rare species per unit area is used as a quantitative indicator of the role of local rare species in maintaining global biodiversity. By measuring biodiversity from these three perspectives (potential, contribution and significance) simultaneously, biodiversity conservation strategies are addressed for different regions. Taking China as a case study, it shows that the provinces featuring high potential, low contribution and low significance can moderately increase biodiversity development. The provinces with high significance to global biodiversity should strengthen conservation to halt biodiversity loss. The areas exhibiting overexploitation of biodiversity should in turn restrict biodiversity exploitation. The general approaches proposed in this study could be applied to different cases, situations and species, promoting the integration to biodiversity conservation actions at different scales.
... Plant species diversity is known to have positive effects on ecosystem functioning. In particular, a lot of studies highlighted a positive effect of species diversity on productivity (Hector et al. 1999;Hooper and Vitousek 1997;Tilman et al. 1996;Yachi and Loreau 1999) with evidence that functional group richness, and further, functional dissimilarity between groups (Heemsbergen et al. 2004), play a greater role than species richness per se (Balvanera et al. 2006;Grime 1997). The mechanisms that could explain a positive diversity-productivity relationship are often grouped under two main categories of effects: "complementarity effects" (i.e. ...
PurposeThe effect of plant species and genotypic diversity on productivity has been well documented but little is known about the contribution of the interaction between species and genotypic diversity. Since the influence of soil microorganisms on the plant diversity-productivity relationship is increasingly recognized, we investigated potential interactions between plant species diversity, plant genotypic diversity and soil microbes. We hypothesized that the non-additive effects of plant species and genotypic diversity on productivity could be microbe-driven.Methods
We set up pea and wheat monocultures and mixtures in a growth chamber, varying for their levels of genotypic diversity under three different soil microbial contexts. We assessed plant shoot and root biomass production, soil mineral nitrogen content and described the soil bacterial communities.ResultsWe found that shoot biomass in mixtures involving both species and genotypic diversity was higher than expected considering the additive effects of plant species diversity and genotypic diversity. Rather than a synergy between two positive effects of species and genotypic diversity, we observed that species mixture compensated the negative effect of genotypic diversity. Regarding microbial influence, we found that the effect of plant species diversity, plant genotypic diversity and their interaction on productivity were all driven by the soil microbial community as no effect was observed in a pre-sterilised soil.Conclusion
Our study suggests that the plant diversity-productivity relationship could be shaped by a three-way interaction between plant species diversity, plant genotypic diversity and soil microbes. Thus, plant-microbe and plant-plant interactions could be a determinant of the plant diversity-productivity relationship.
... Nutrient enrichment, alteration of riparian vegetation, riverbed regulation, and alteration of the hydrological regime of the river, strongly influence the structure and function of ecosystems. Such changes significantly impact all processes within the ecosystem [2][3][4] as they disrupt its natural balance and ecosystem function [5,6]. ...
The present research aimed to determine the diversity of macrophyte taxa in the Ljubljanica River and its relationship with environmental parameters. In each of the 19 river sections, the presence and abundance of plant taxa were recorded, and basic physical and chemical parameters were measured. Additionally, selected environmental parameters were assessed using a modified version of the Riparian, Channel and Environmental (RCE) method. We compared the obtained data set with survey data from the year 2004. In 2019, a total of 34 macrophyte taxa were recorded. The dominant taxa with the highest abundance were Sparganium emersum, Callitriche sp., and the invasive alien species Elodea canadensis. The species richness and diversity of macrophytes decreased with distance from the source, an increase in pH, and alterations of the riverbed structure due to interference in the riverine ecosystem in the lower part of the Ljubljanica River and its catchment. The comparison of 2004 and 2019 surveys revealed a decrease in the overall presence and abundance of P. natans and in the frequency of occurrence of the species Myriophyllum spicatum and an increase in the presence and abundance of the invasive alien species Elodea canadensis.
This paper illuminates primary epistemic functions of teleological characterizations in ecology through discussion of the historical and conceptual origins of the theoretical branch of ecology (§§1-2). I subsequently defuse enduring confusions about the use of teleological characterizations in ecology; with a focus on recent critical arguments by Sagoff in this journal (2016) and some other places (e.g., his 2013 and 2017) (§3). The paper then culminates by collecting five generalizable novel insights attained through the forgoing discussion and outlining avenues for follow-up work that can build on the arguments laid out in this paper (§4).
In this work, we focused on the functional characterization of unicellular eukaryotic assemblages that had previously been taxonomically characterized by 18S rRNA gene amplicon sequencing in a eutrophic coastal site with marked plankton blooms. Biological traits of different functional groups were assigned to the retrieved operational taxonomic units (OTUs). The traits included size, trophic strategy, the presence of spines, mucilage production, colony formation, motility, spore formation, and potential harmfulness. Functional diversity indices were calculated and compared to analogous taxonomic diversity indices, indicating a strong positive coupling of richness and dominance and a negative coupling of evenness, even at a low taxonomic resolution (at the family/genus/species level). Biological trait trade-offs and co-occurrences of specific traits were evident during the succession of plankton blooms. The trophic strategy dominating in the assemblages frequently alternated between autotrophy, mixotrophy, and a few recorded cases of parasitism. Given that there was no indication of nutrient limitation, we suggest that biotic pressures force marine eukaryotes to exploit narrow niches by adopting specific strategies/traits that favour their survival. These traits act by increasing resource acquisition potential and via predator avoidance. This leads to a unique succession of blooms in the system, characterized by adaptations of the bloom taxa that are a direct response to the preceding assemblage.
What can ecological science contribute to the sustainable management and conservation of the natural systems that underpin human well-being? Bridging the natural, physical and social sciences, this book shows how ecosystem ecology can inform the ecosystem services approach to environmental management. The authors recognise that ecosystems are rich in linkages between biophysical and social elements that generate powerful intrinsic dynamics. Unlike traditional reductionist approaches, the holistic perspective adopted here is able to explain the increasing range of scientific studies that have highlighted unexpected consequences of human activity, such as the lack of recovery of cod populations on the Grand Banks despite nearly two decades of fishery closures, or the degradation of Australia's fertile land through salt intrusion. Written primarily for researchers and graduate students in ecology and environmental management, it provides an accessible discussion of some of the most important aspects of ecosystem ecology and the potential relationships between them.
What can ecological science contribute to the sustainable management and conservation of the natural systems that underpin human well-being? Bridging the natural, physical and social sciences, this book shows how ecosystem ecology can inform the ecosystem services approach to environmental management. The authors recognise that ecosystems are rich in linkages between biophysical and social elements that generate powerful intrinsic dynamics. Unlike traditional reductionist approaches, the holistic perspective adopted here is able to explain the increasing range of scientific studies that have highlighted unexpected consequences of human activity, such as the lack of recovery of cod populations on the Grand Banks despite nearly two decades of fishery closures, or the degradation of Australia's fertile land through salt intrusion. Written primarily for researchers and graduate students in ecology and environmental management, it provides an accessible discussion of some of the most important aspects of ecosystem ecology and the potential relationships between them.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
There are often blanket claims that the world is facing more problems than ever but there is a lack of empirical data to show where things have deteriorated or in fact improved. In this book, some of the world's leading economists discuss ten problems that have blighted human development, ranging from malnutrition, education, and climate change, to trade barriers and armed conflicts. Costs of the problems are quantified in percent of GDP, giving readers a unique opportunity to understand the development of each problem over the past century and the likely development into the middle of this century, and to compare the size of the challenges. For example: how bad was air pollution in 1900? How has it deteriorated and what about the future? Did climate change cost more than malnutrition in 2010? This pioneering initiative to provide answers to many of these questions will undoubtedly spark debate amongst a wide readership.
The absence of a species from a focal community may be due to either dispersal limitation or recruitment limitation. The present work aims to assess species behavior in different types of landscapes. I first investigated the relationship between alpha and gamma diversity at different scales and for different fragmentation levels in forest fragments embedded in an agricultural landscape matrix. Results highlight the importance of considering species identity when studying the effect of fragmentation on the plant community structure. I then assessed the germination success and persistence of vascular plant species (weeds and herbaceous plants), using semi-controlled experiments. In the first experiment, I studied the germination and persistence success of sown weed species, and their subsequent effect on crop yield, under contrasted agricultural practices. We evidenced a sorting effect of agricultural practices on local plant species composition. In the second experiment, I assessed the potential of hedgerows to serve as habitats for forest plant species. We sought seeds and transplanted seedlings in both hedgerows and forest to monitor germination and persistence, respectively, each time with and without resident vegetation removal to further assess the role of competition. Our preliminary results show that few species germinate and survive in hedgerows, suggesting that both dispersal and recruitment limitations are at play. Results from this work emphasize the importance of community assembly processes in ecosystem conservation and maintaining its delivered services
Taxonomic, functional, and phylogenetic diversities are important facets of biodiversity. Studying them together has improved our understanding of community dynamics, ecosystem functioning, and conservation values.1–3 In contrast to species, traits, and phylogenies, the diversity of biotic interactions has so far been largely ignored as a biodiversity facet in large-scale studies. This neglect represents a crucial shortfall because biotic interactions shape community dynamics, drive important aspects of ecosystem functioning,4–7 provide services to humans, and have intrinsic conservation value.8,9 Hence, the diversity of interactions can provide crucial and unique information with respect to other diversity facets. Here, we leveraged large datasets of trophic interactions, functional traits, phylogenies, and spatial distributions of >1,000 terrestrial vertebrate species across Europe at a 10-km resolution. We computed the diversity of interactions (interaction diversity [ID]) in addition to functional diversity (FD) and phylogenetic diversity (PD). After controlling for species richness, surplus and deficits of ID were neither correlated with FD nor with PD, thus representing unique and complementary information to the commonly studied facets of diversity. A three-dimensional mapping allowed for visualizing different combinations of ID-FD-PD simultaneously. Interestingly, the spatial distribution of these diversity combinations closely matched the boundaries between 10 European biogeographic regions and revealed new interaction-rich areas in the European Boreal region and interaction-poor areas in Central Europe. Our study demonstrates that the diversity of interactions adds new and ecologically relevant information to multifacetted, large-scale diversity studies with implications for understanding eco-evolutionary processes and informing conservation planning.
Community structure varies over time as changing environmental conditions favor some species over others. Succession during recovery from disturbance typically proceeds as a relatively predictable sequence of communities, starting with the initial pioneer community that develops in the wake of disturbance. Community dominance gradually shifts from a few highly mobile species that are tolerant of exposure to harsh conditions to a greater diversity of more competitive species that create an increasingly interactive community more characteristic of the biome within which it occurs. Long disturbance-free intervals may lead to competitive exclusion of some species, resulting in a decline in diversity. Paleoecological study provides clues to factors that affect long-term changes in community structure. Apparently declining insect abundance in the Northern Hemisphere may reflect changes in climate or land use. However, more long-term studies using consistent sampling techniques are needed in more locations in order to assess trends in insect abundances.
This paper explores interactions between ecological science and conservation values in the biodiversity-ecosystem function (BEF) debate of the 1990–2000s. The scientific debate concerned the interpretation of observed correlations between species richness and ecosystem properties like primary productivity in experimental ecosystems. The debate over the causal or explanatory role of species richness was presumed to have implications for conservation policy, and the use of such research to support policy recommendations generated hostility between rival groups of ecologists. I argue that the debate was due in part to the adoption of a broad conception of biodiversity as a goal and value in conservation politics and ethical debates, and the ecologists who questioned the causal efficacy of species richness were also suggesting problems with this goal. I characterize what I call the “uneasy consensus” established by BEF researchers in the late 2000s, discuss roles for values in BEF research, and suggest that this episode shows that ecological science can itself be an important site for ethical debates about conservation values.
As part of the implementation of the provisions of the European Landscape Convention, a landscape audit of the provinces has been underway in Poland for a few years. The main objectives of the audit are the delimitation of landscape units, assessment of their values, and identification of the priority of landscapes to be protected. This study presents the results of research on the landscape division of the Wielkopolskie voivodeship and a geostatistical analysis of the differentiation of ecological units. With reference to legal regulations in force in Poland, the landscape diversity of the province was characterized using two divisions: geophysical regionalization and landscape typology. In the case of regional division, the meso- and microregions of physical and geographical rank are referenced. The proposed microregional division is the first example in Poland of such a detailed landscape analysis completed for the area of the voivodeship. In the case of typological division, the study conducted in cooperation with the Wielkopolska Bureau of Spatial Planning in Poznań was used. The statistical analysis included metrics to quantitatively characterize landscape composition, including the landscape division index (DIVISION), Shannon’s diversity index (SHDI), and Simpson’s diversity index (SIDI). The results of the study were then compared with the distribution of areas associated with different forms of landscape protection such as national parks, landscape parks, and protected landscape areas. The applied methodology and the results obtained indicate the important role of physical and geographical microregions in the complex analyses of landscape diversity and their broad application in procedures connected with landscape planning and environmental protection.
В работе представлены результаты исследований развития представлений о функционировании и динамике региональных экосистем. Особое внимание уделено функционированию и динамике экосистем на фоне климатических изменений. Выявлены этапы развития представлений о функционировании и динамике экосистем. Показано развитие представлений в мировой и российской научных традициях. Особое внимание уделено роли крымских научных школ в развитии теории и методологии исследований функционирования и динамики экосистем. Показано, что, несмотря на значительное количество публикаций в этом направлении, вопросы теории и методологии изучения процессов функционирования и динамики региональных экосистем в условиях климатических изменений до конца не разработаны.
L’étude porte sur la connaissance et le suivi du phénomène de désertification au niveau de la wilaya de Saida via les techniques de couplages entre le diagnostic phytoécologique et les données de la géomatique (images LANDSAT : 1988 et 2013), Dans une première étape, une étude diachronique du couvert végétal a été effectuée par des traitements spectraux basés sur les indices de végétation (SAVI).Dans une deuxième étape, une cartographie de sensibilité à la désertification a été établie par la combinaison de plusieurs facteurs. Dans une troisième étape toutes les données cartographiques sont saisies dans une base de données (SGBD). Ce qui a permis de mieux cibler les interventions par la proposition d’un modèle d’aménagement.
Environmental damage due to natural resource extraction, especially in watershed areas, seems to be of increasing concern and so far, from the aspect of aquatic and water resources, plankton is commonly used as an indicator of environmental damage. This study explores the distribution of microphyta as a parameter of environmental damage. The research was conducted in Pager watershed, Central Kalimantan and sampled at 2 (two) stations, namely station A (for the right side of the river) and station B (for the left side of the river). The study was conducted 13 sampling times, which began in the period 25 May 2019 ending until 9 November 2019. Laboratory analysis to identify the type and number of microphyta was carried out at the Palangka Raya University Laboratory. The results showed that the number of microphyta taxa at station A (right side of the river) was 12-13 species, more than station B (left side of the river). The number of microphyta taxa at Station B is 8 - 9 species, it is suspected that there is an influence from the gray water settlements around the left side, especially when the water level drops. The distribution characteristics of microphyta in the Pager river are as follows: large number of taxa/species, low abundance and low diversity index. River/peat water environments are vulnerable to change, especially human interference. This research shows the potential use of microphyta as an indicator of environmental damage.
Seed banks are important in wetland vegetation, but their role on lakeshores has received little attention. The influence of seed banks on lakeshore vegetation was investigated near eastern Georgian Bay in Ontario, where there is a rich shoreline and aquatic flora. Some lakeshore species found there can be considered “coastal plain disjuncts” similar to those of southwestern Michigan and adjacent Indiana, and central Wisconsin. Matchedash Lake in Simcoe Co., Ontario, has a particularly rich assemblage of these shoreline species. Based on short-term records, and aging of drowned stumps, we demonstrated that yearly mean water levels can and have changed by more than a meter. Such water-level fluctuations partly result from beaver dams on the single outlet stream. Vegetation data collected in a low-water phase (1976) document a rich shoreline flora, largely absent in the present (1979) high-water phase. During this latter high-water phase, we collected 15 sediment sample units from each of six water depths (0–1.5 m). The sample, representing 0.32 m² of lake bottom, was planted out in a greenhouse; 3,149 seedlings representing 41 species of vascular plants emerged. Six (Rhexia virginica, Rhynchospora capitellata, Panicum spretum, Xyris difformis, Polygonum cureyi, Linum striatum) are rare in Ontario. Estimated seed banks for individual species were as high as 6,500 seeds m“². If another low-water phase occurs, a rich shoreline flora should again develop. We hypothesize that water-level fluctuations are essential to the long-term survival of these species.
Humans are modifying both the identities and numbers of species in ecosystems, but the impacts of such changes on ecosystem
processes are controversial. Plant species diversity, functional diversity, and functional composition were experimentally
varied in grassland plots. Each factor by itself had significant effects on many ecosystem processes, but functional composition
and functional diversity were the principal factors explaining plant productivity, plant percent nitrogen, plant total nitrogen,
and light penetration. Thus, habitat modifications and management practices that change functional diversity and functional
composition are likely to have large impacts on ecosystem processes.
ONE of the ecological tenets justifying conservation of biodiversity is that diversity begets stability. Impacts of biodiversity on population dynamics and ecosystem functioning have long been debated1-7, however, with many theoretical explorations2-6,8-11 but few field studies12-15. Here we describe a long-term study of grasslands16,17 which shows that primary productivity in more diverse plant communities is more resistant to, and recovers more fully from, a major drought. The curvilinear relationship we observe suggests that each additional species lost from our grasslands had a progressively greater impact on drought resistance. Our results support the diversity-stability hypothesis5,6,18,19, but not the alternative hypothesis that most species are functionally redundant19-21. This study implies that the preservation of biodiversity is essential for the maintenance of stable productivity in ecosystems.
The relative effects of plant richness (the number of plant functional groups) and composition (the identity of the plant
functional groups) on primary productivity and soil nitrogen pools were tested experimentally. Differences in plant composition
explained more of the variation in production and nitrogen dynamics than did the number of functional groups present. Thus,
it is possible to identify and differentiate among potential mechanisms underlying patterns of ecosystem response to variation
in plant diversity, with implications for resource management.
Interactions between biotic and abiotic processes complicate the design and interpretation of ecological experiments. Separating causality from simple correlation requires distinguishing among experimental treatments, experimental responses, and the many processes and properties that are correlated with either the treatments or the responses or both. When an experimental manipulation has multiple components, but only one of them is identified as the experimental treatment, erroneous conclusions about cause and effect relationships are likely because the actual cause of any observed response may be ignored in the interpretation of the experimental results. This unrecognised cause of an observed response can be considered a "hidden treatment". Three types of hidden treatments are potential problems in biodiversity experiments:
(1) abiotic conditions, such as resource levels, or biotic conditions, such as predation, which are intentionally or unintentionally altered in order to create differences in species numbers for"diversity" treatments;
(2) non-random selection of species with particular attributes that produce treatment differences that exceed those due to "diversity" alone;
(3) the increased statistical probability of including a species with dominant negative or positive effect (e.g. dense shade, or nitrogen fixation) in randomly selected groups of species of increasing number or "diversity".
In each of these cases, treatment responses that are actually the result of the "hidden treatment" may be inadvertently attributed to variation in species number. Case studies re-evaluating three different types of biodiversity experiments demonstrate that the increases found in such ecosystem properties as productivity, nutrient use efficiency, and stability (all of which were attributed to higher level of species diversity) were actually caused by "hidden treatments" that altered plant biomass and productivity.
We test the hypothesis that the responses of vegetation to extreme events is a function of the nutrient stress tolerance of species present. The nutrient stress tolerance of a range of species was defined by a formalized procedure in which traits measured by screening in the laboratory were synthesized using principle components analysis. 2. Results were then compared with the results from a large-scale field experiment which examined the responses of five herbaceous plant communities in Derbyshire, UK to three extreme events (frost, drought and fire). 3. Nutrient stress tolerance was positively correlated with resistance to initial damage and negatively correlated with resilience (speed of recovery). The results illustrate the use of laboratory data to predict the field responses of plants to extreme events and demonstrate that the axis from high to low nutrient stress tolerance can play an effective role in predicting these responses.
IN maintaining or reconstructing types of herbaceous vegetation in which
the density of flowering plants exceeds 20 species/m2-the
so-called ``species-rich'' communities, success is often frustrated by
competitive exclusion. Here I describe an attempt to identify criteria
with which to assess or anticipate the effect of competitive exclusion
both at individual sites and in different types of vegetation.
The essence of the contradiction between traditional ecological complexity-stability hypothesis and recent theoretical results is clarified. The distinction between resilience and resistance is stressed. The possibilities of field verification of May's model are discussed. No satisfactory method for estimation of connectance and mean interaction strength in plant communities has been found. Relation between these parameters and stability in real communities remains an open question. The relation between connectance and stability (resilience) in purely competitive model communities is more complicated than May's rule predicts. The certain value of connectance having been achieved, stability increases with increasing connectance. We assessed the positive relation between species diversity and resistance, and negative relation between species diversity and resilience in plant communities during old-field succession in xeric habitat. But there is no causal relationship between species diversity and both kinds of stability. Resistance and resilience of the plant communities studied were determined primarily by life history strategies of constituent species. The results are interpreted in terms of Grimes' life history strategies and imply the validity of Gleasonian, population-centered explanation of community phenomena.
The relationships between biodiversity and stability were determined for both population and ecosystem traits in a long-term study of 207 grassland plots. Results demonstrate that biodiversity stabilises community and ecosystem processes, but not population processes. Specifically, year to year variability in total aboveground plant community biomass was significantly lower in plots with greater species variability both for the entire 11-year period and for the 9 non-drought years. The change in total plant community biomass from before the drought to the peak of the drought was also highly dependent on species richness. For all three measures of total community biomass stability, multiple regressions that controlled co-variates showed similar relationships between plant diversity and stability.
In contrast, year to year variability in species abundance was not stabilised by plant species richness for either all years or non-drought years. This difference between species vs. community biomass likely results from interspecific competition. When climatic variations harm some species, unharmed competitors increase. Such compensatory increases stabilise total community biomass, but cause species abundances to be more variable. These results support both the predictions of Robert May concerning the effects of diversity on population stability and the diversity-stability hypothesis as applied to community and ecosystem processes, thus helping to reconcile a long-standing dispute.
COMMUNITIES of species and their associated biological, chemical and
physical processes, collectively known as ecosystems, drive the Earth's
biogeochemical processes1,2. Currently most ecosystems are
experiencing loss of biodiversity associated with the activities of
human expansion3-5, raising the issue of whether the
biogeochemical functioning of ecosystems will be impaired by this loss
of species6-8. Current ecological knowledge supports a wide
range of views on the subject9-13, but empirical tests are
few9,14-16. Here we provide evidence from direct experimental
manipulation of diversity by over an order of magnitude, using
multi-trophic level communities and simultaneous measures of several
ecosystem processes, that reduced biodiversity may indeed alter the
performance of ecosystems.
Identifies some of the essential features of dominant and subordinate plants of terrestrial plant communities and considers how knowledge relating to them can contribute to understanding of vegetation characteristics. -from Author