Article

The Holdridge life zones of the conterminous United States in relation to ecosystem mapping

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  • International Institute of Tropical Forestry
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Abstract

Aim Our main goals were to develop a map of the life zones for the conterminous United States, based on the Holdridge Life Zone system, as a tool for ecosystem mapping, and to compare the map of Holdridge life zones with other global vegetation classification and mapping efforts. Location The area of interest is the forty-eight contiguous states of the United States. Methods We wrote a PERL program for determining life zones from climatic data and linked it to the image processing workbench (IPW). The inputs were annual precipitation (Pann), biotemperature (Tbio), sea-level biotemperature (T0bio), and the frost line. The spatial resolution chosen for this study (2.5 arc-minute for classification, 4-km for mapping) was driven by the availability of current state-of-the-art, accurate and reliable precipitation data. We used the Precipitation-elevation Regressions on Independent Slopes Model, or PRISM, output for the contiguous United States downloaded from the Internet. The accepted standard data for air temperature surfaces were obtained from the Vegetation/Ecosystem Modelling and Analysis Project (VEMAP). This data set along with station data obtained from the National Climatic Data Center for the US, were used to develop all temperature surfaces at the same resolution as the Pann. Results The US contains thirty-eight life zones (34% of the world's life zones and 85% of the temperate ones) including one boreal, twelve cool temperate, twenty warm temperate, four subtropical, and one tropical. Seventy-four percent of the US falls in the ‘basal belt’, 18% is montane, 8% is subalpine, 1% is alpine, and < 0.1% is nival. The US ranges from superarid to superhumid, and the humid province is the largest (45% of the US). The most extensive life zone is the warm temperate moist forest, which covers 23% of the country. We compared the Holdridge life zone map with output from the BIOME model, Bailey's ecoregions, Küchler potential vegetation, and land cover, all aggregated to four cover classes. Despite differences in the goals and methods for all these classification systems, there was a very good to excellent agreement among them for forests but poor for grasslands, shrublands, and nonvegetated lands. Main conclusions We consider the life zone approach to have many strengths for ecosystem mapping because it is based on climatic driving factors of ecosystem processes and recognizes ecophysiological responses of plants; it is hierarchical and allows for the use of other mapping criteria at the association and successional levels of analysis; it can be expanded or contracted without losing functional continuity among levels of ecological complexity; it is a relatively simple system based on few empirical data; and it uses objective mapping criteria.

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... O zoneamento ecológico de um espaço geográfico é uma ferramenta chave que permite reconhecer a heterogeneidade ambiental e classificar unidades ecológicas homogêneas (LUGO et al., 1999). Dentre as variáveis ambientais com maior utilização no mapeamento de unidades ecológicas, destaca-se o clima, uma vez que as comunidades de plantas e animais, bem como as propriedades do solo são fortemente controladas pelas condições climáticas predominantes (HOLDRIDGE, 2000). ...
... O clima pode ser entendido como o conjunto de condições meteorológicas que incidem sobre determinado local ou região (ISAAC; BOURQUE, 2001). Dado que o clima pode variar em escala espacial e temporal, compreender o seu funcionamento tratase de uma tarefa bastante complexa (LUGO et al., 1999;ISAAC;BOURQUE, 2001;TATLI;DALFES, 2016). Sendo assim, para superar tal complexidade, uma estratégia eficaz é a categorização do clima em subclasses (LUGO et al., 1999). ...
... Dado que o clima pode variar em escala espacial e temporal, compreender o seu funcionamento tratase de uma tarefa bastante complexa (LUGO et al., 1999;ISAAC;BOURQUE, 2001;TATLI;DALFES, 2016). Sendo assim, para superar tal complexidade, uma estratégia eficaz é a categorização do clima em subclasses (LUGO et al., 1999). ...
Article
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A definição das zonas de vida de Holdridge é uma ferramenta útil para o planejamento da gestão territorial dos recursos naturais, bem como para subsidiar a elaboração de estratégias e políticas públicas que resultem na definição de áreas prioritárias para conservação e uso sustentável das florestas. Desse modo, o presente estudo teve por objetivo identificar e descrever as zonas de vida que ocorrem no estado do Ceará com base no modelo de Holdridge. Para esse propósito, foram utilizados dados de precipitação anual, biotemperatura e relação de evapotranspiração potencial. Os resultados indicaram que, embora o estado do Ceará esteja majoritariamente sob a influência de um macroclima semiárido, apresenta um espaço geográfico heterogêneo, no qual ocorrem diferentes zonas de vida associadas à diversidade bioclimática. A variável bioclimática mais importante para a classificação das zonas de vida foi a relação de evapotranspiração potencial, que representa a quantidade de água que é transferida para a atmosfera em relação a quantidade de água que é precipitada em determinado local. A classificação climática de Holdridge identificou oito zonas de vida em que todas pertencem à faixa latitudinal tropical e abrangem faixas altitudinais basais (90,04% do território cearense) e premontanas (9,96%), que variam em termos de umidade, desde florestas muito secas até florestas úmidas. A zona de vida mais extensa compreende as áreas de transição entre floresta muito seca e floresta seca tropical basal, ocupando 64.825,69 km2, que recobre 43,54% da área total do estado.
... Yates et al. 2000;Yue et al. 2001;Enquist 2002;Sisneros et al. 2011). In this sense, the Holdridge life zone system (Holdridge 1967) is a wellestablished bioclimatic classification that identifies ecological units (life zones) representing conditions for ecosystem functioning (Lugo et al. 1999). The Holdridge life zone system is particularly attractive because it is a simple system based on few empirical data (i.e. ...
... In addition, the boundaries of ecoregions and life zones can tend to be coincident in climate-controlled ecoregions. However, such correspondence between ecoregions and bioclimates can vary across space, simply because the two classifications use different methodological conceptions (Bailey 1983;Lugo et al. 1999;Odom & Ford 2020). For example, in the US, Lugo et al. (1999) found good agreement between ecoregions and life zones in forested areas, but poor agreement in grasslands, shrublands and nonvegetated lands. ...
... However, such correspondence between ecoregions and bioclimates can vary across space, simply because the two classifications use different methodological conceptions (Bailey 1983;Lugo et al. 1999;Odom & Ford 2020). For example, in the US, Lugo et al. (1999) found good agreement between ecoregions and life zones in forested areas, but poor agreement in grasslands, shrublands and nonvegetated lands. At the same time, future changes in bioclimatic conditions within ecoregions are expected to result in ecosystem changes (Bailey 2014), but the strength of the effects can vary across ecoregions. ...
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Modelling the potential impacts of future climate on ecosystems provides important information for environmental planning and management. The Holdridge life zones system is a land classification based on simple bioclimatic variables that can be used for evaluating the potential effect of future climates on ecosystems. However, information on future bioclimatic changes in ecoregions of southern South America is too coarse, or unavailable. Our main goals were to evaluate the usefulness of a simple bioclimatic classification system to assess the potential effects of climate change on ecological systems, and to what extent such changes would affect the ecoregions of Argentina. We analysed the multivariate distance between ecoregions of Argentina based on the area occupied by each life zone in each ecoregion and conducted an ordination of ecoregions under current and future climate scenarios. We also evaluated the correspondence between the boundaries of ecoregions and life zones. Overall, the ecoregions of Argentina are expected to face substantial change in bioclimatic conditions. In particular, ecoregions at high latitudes (e.g. Bosques Patagonicos) or altitudes (e.g. Altos Andes) are projected to exhibit similar bioclimatic conditions to ecoregions at lower latitudes or altitudes under current climate (e.g. Estepa Patagonica, Puna). The boundaries of ecoregions tended to coincide with those of life zones only in two cases and partial coincidence was the most frequent result. Further, the analysis of uncertainties of local climate data allowed to identify ecoregions where the results might be less reliable. Our study provides insights to improve conservation planning and management in Argentina. Integrating ecoregions and Holdridge life zones proved to be a useful approach for understanding the potential effects of future climate changes on ecological systems.
... The life zone classification system (Holdridge, 1947) provides a straightforward, intuitive, and sound approach to distinguishing landscape-scale ecosystems and features several important strengths: (i) life zones are dynamic and defined directly from quantitative climate data, without reliance on subjective expert delineation (Olson et al., 2001) or remote sensing (Chen et al., 2015), which are not available for past or future periods; (ii) life zones are based on continuous rather than categorical measures, unlike alternative climate classifications (Beck et al., 2018); (iii) the climatic variables defining life zones directly constrain ecological and ecophysiological processes relevant to the conservation and management of natural resources (Lugo et al., 1999); (iv) life zones have been tested and validated for accuracy, and perform particularly well in forest and tropical landscapes (Pan et al., 2010); life zones closely align with other broad ecosystem classification systems including land cover, potential vegetation, ecoregions, and the IUCN Global Ecosystem Typology slated for adoption by the Convention on Biological Diversity (CBD) (Keith et al., 2020;Lugo et al., 1999). ...
... The life zone classification system (Holdridge, 1947) provides a straightforward, intuitive, and sound approach to distinguishing landscape-scale ecosystems and features several important strengths: (i) life zones are dynamic and defined directly from quantitative climate data, without reliance on subjective expert delineation (Olson et al., 2001) or remote sensing (Chen et al., 2015), which are not available for past or future periods; (ii) life zones are based on continuous rather than categorical measures, unlike alternative climate classifications (Beck et al., 2018); (iii) the climatic variables defining life zones directly constrain ecological and ecophysiological processes relevant to the conservation and management of natural resources (Lugo et al., 1999); (iv) life zones have been tested and validated for accuracy, and perform particularly well in forest and tropical landscapes (Pan et al., 2010); life zones closely align with other broad ecosystem classification systems including land cover, potential vegetation, ecoregions, and the IUCN Global Ecosystem Typology slated for adoption by the Convention on Biological Diversity (CBD) (Keith et al., 2020;Lugo et al., 1999). ...
... While each life zone has a phyto-geographic name, such as "moist forest" (Figure 1e), these describe potential vegetation. Local environmental variation in, for example, slope and soil type, as well as human activities, influence fine-scale vegetation characteristics and the overall condition, land cover, and land use of the landscapes (Lugo et al., 1999). Holdridge (1947) used the frost line to determine the boundary between warm temperate and subtropical life zones. ...
Article
Rapid climate change is impacting biodiversity, ecosystem function, and human well‐being. Though the magnitude and trajectory of climate change are becoming clearer, our understanding of how these changes reshape terrestrial life zones—distinct biogeographic units characterized by biotemperature, precipitation, and aridity representing broad‐scale ecosystem types—is limited. To address this gap, we used high‐resolution historical climatologies and climate projections to determine the global distribution of historical (1901‐1920), contemporary (1979‐2013), and future (2061‐2080) life zones. Comparing the historical and contemporary distributions shows that changes from one life zone to another during the 20th century impacted 27 million km2 (18.3% of land), with consequences for social and ecological systems. Such changes took place in all biomes, most notably in Boreal Forests, Temperate Coniferous Forests, and Tropical Coniferous Forests. Comparing the contemporary and future life zone distributions shows the pace of life zone changes accelerating rapidly in the 21st century. By 2070, such changes impact an additional 62 million km2 (42.6% of land) under ‘business‐as‐usual’ (RCP8.5) emissions scenarios. Accelerated rates of change are observed in hundreds of ecoregions across all biomes except Tropical Coniferous Forests. While only 30 ecoregions (3.5%) had over half of their areas change to a different life zone during the 20th century, by 2070 this number is projected to climb to 111 ecoregions (13.1%) under RCP4.5 and 281 ecoregions (33.2%) under RCP8.5. We identified weak correlations between life zone change and threatened vertebrate richness, levels of vertebrate endemism, cropland extent, and human population densities within ecoregions, illustrating the ubiquitous risks of life zone changes to diverse social‐ecological systems. The accelerated pace of life zone changes will increasingly challenge adaptive conservation and sustainable development strategies that incorrectly assume current ecological patterns and livelihood provisioning systems will persist.
... To do that, we used a large ensemble of Regional Climate Models (RCMs) from the datasets of the Coordinated Regional Climate Downscaling Experiment (CORDEX; Giorgi et al., 2009). Following the approach of the third edition of World Atlas of Desertification (Cherlet et al., 2018), we complemented the FAO-UNEP AI with two other indicators, to provide more robust estimations of arid areas: the Köppen-Geiger climate classification (KG; Köppen, 1936;Geiger, 1954), which provides a more refined climate classification than AI (Peel et al., 2007), and the Holdridge Life Zones (HDG; Holdridge and Tosi, 1967), which can be used to incorporate more explicitly ecosystem processes (Lugo et al., 1999). ...
... The number of classes in the HDG system ranges between thirty-one and thirty-six, due to a variable number of subdivisions for cold climate (Szelepcsényi et al., 2014). In this study, to delineate arid areas using HDG, we selected the sub-classes desert, desert scrub, thorn woodland, thorn steppe, and very dry forest (see the naming scheme in Lugo et al. (1999). Such classes are characterized by annual PET to precipitation ratio larger than 2, annual precipitation below 1000 mm, and bio-temperature higher than 3 • C. ...
... The HDG method is commonly applied to classify zones according to mixed vegetation and climate features, as in Lugo et al. (1999), Chen et al. (2003), Ze-meng and Tian-xiang (2005), Szelepcsényi et al. (2018), Tatli and Dalfes (2016), Derguy et al. (2019). ...
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One of the possible consequences of projected global warming is the progressive enlargement of drylands. This study investigates to what extent population and land-use (forests, pastures, and croplands) are likely to be in areas turning arid in the 21st century. The first part of the study focuses on the climatological enlargement of arid areas at global, macro-regional, and high-resolution (0.44°) scales. To do so we analysed a large ensemble of CORDEX climate simulations, combined three indicators (FAO-UNEP aridity index, Köppen-Geiger climate classification, and Holdridge life zones), and quantified the areas turning from climatologically not arid into climatologically arid (and vice-versa) from recent past (1981–2010) to four projected global warming levels (GWLs) from 1.5°C to 4°C. In the second part, we used population and land-use projections to analyze their exposure to progressive shifts to drier or wetter climate. Both types of projections follow five socio-economic scenarios (SSPs from SSP1 to SSP5). We present results for the viable combinations between SSPs and GWLs. Depending on GWL, the projected drying patterns show regional differences but, overall, the negative consequences of climate change are clear. Already at 1.5°C warming, approximately 2 million km2 (1.4% of global land) are likely to become arid; at 2°C this area corresponds to 2.6 million km2 (2.7%), at 3°C to 5.2 million km2 (3.5%), and at 4°C to 6.8 million km2 (4.5%), an area that can be ranked the seventh largest country in the World. Such drying is particular strong over South America and southern Europe. In the worst-case scenario (SSP3, regional rivalry, at 4°C), approximately 500 million people will live in areas shifting towards arid climate. Forest areas are likely to be more affected in South America, pastures in Africa, and croplands in the Northern Hemisphere. For land-use, the worst-case scenarios are SSP3 and SSP5 (fossil-fuel based future): at GWL 4°C, about 0.5 million km2 of forests and 1.2 million km2 of both pastures and croplands are likely to be in areas shifting to arid climate.
... A previously published model used absolute minimum temperatures to define the southern boundary of boreal forest [31], and other work has indicated that a minimum winter temperature threshold defines the limits of the interior boreal forest from coastal hemlock-spruce forest in Alaska [32]. A model tried here used both winter minimum monthly temperature and mean summer temperature to define boreal forest, but resulted in an anomalous boreal patch in northwestern Wisconsin that is currently, and has historically been occupied by mixed forest, rather than boreal forest [33][34][35]. Therefore, the temperature bound in Equation (7) adjusted for continentality was used. ...
... It is supported in a recent study by Chaffin [55] who found that temperate species of all size classes decreased dramatically from West to East across the Boundary Waters Canoe Area Wilderness, and were almost entirely absent in the eastern third of the wilderness and adjacent northeastern MN. Finally, the area in northeastern Minnesota mapped as boreal here also corresponds very well to an area previously mapped as subalpine wet forest [33], which is equivalent here to boreal forest. ...
... In addition, fire use by Native Americans prior to European settlement allowed some areas of prairie to exist east of the border as defined by climate [3]. Other analyses of biome climate envelopes for the late 20th Century [10,33], also place the prairie-forest border in a north-south orientation right along the western edge of Minnesota, and eastern North Dakota and South Dakota, while Gonzalez et al. [57] places it also in a north-south orientation, but slightly further west. ...
Article
Research Highlights: We modeled climate-biome envelopes at high resolution in the Western Great Lakes Region for recent and future time-periods. The projected biome shifts, in conjunction with heterogeneous distribution of protected land, may create both great challenges for conservation of particular ecosystems and novel conservation opportunities. Background and Objectives: Climate change this century will affect the distribution and relative abundance of ecological communities against a mostly static background of protected land. We developed a climate-biome envelope model using a priori climate-vegetation relationships for the Western Great Lakes Region (Minnesota, Wisconsin and Michigan USA and adjacent Ontario, Canada) to predict potential biomes and ecotones—boreal forest, mixed forest, temperate forest, prairie–forest border, and prairie—for a recent climate normal period (1979–2013) and future conditions (2061–2080). Materials and Methods: We analyzed six scenarios, two representative concentration pathways (RCP)—4.5 and 8.5, and three global climate models to represent cool, average, and warm scenarios to predict climate-biome envelopes for 2061–2080. To assess implications of the changes for conservation, we analyzed the amount of land with climate suited for each of the biomes and ecotones both region-wide and within protected areas, under current and future conditions. Results: Recent biome boundaries were accurately represented by the climate-biome envelope model. The modeled future conditions show at least a 96% loss in areas suitable for the boreal and mixed forest from the region, but likely gains in areas suitable for temperate forest, prairie–forest border, and prairie. The analysis also showed that protected areas in the region will most likely lose most or all of the area, 18,692 km2, currently climatically suitable for boreal forest. This would represent an enormous conservation loss. However, conversely, the area climatically suitable for prairie and prairie–forest border within protected areas would increase up to 12.5 times the currently suitable 1775 km2. Conclusions: These results suggest that retaining boreal forest in potential refugia where it currently exists and facilitating transition of some forests to prairie, oak savanna, and temperate forest should both be conservation priorities in the northern part of the region.
... The Holdridge system incorporates MAT, mean annual precipitation (MAP), and potential evapotranspiration (PEVT) to define major life zones or biomes. Developed primarily through research in Central America and the Caribbean, this model has been applied in many areas of the world, including North America (Lugo et al. 1999), Australia (Jia et al. 2012), and globally (Emanuel et al. 1985;Olson et al. 2001;Sisneros et al. 2011). Although not designed to be as detailed as more recently developed ecological classifications used in the US (e.g., Cleland et al. 1997;Comer et al. 2003;Omernik and Griffith 2014), the Holdridge system relies directly on simple climatic variables modeled by all GCMs, and in many ways, avoids the complex geologic, edaphic, and floristic components used by other classifications that are difficult to relate objectively to output from GCMs (Lugo et al. 1999). ...
... Developed primarily through research in Central America and the Caribbean, this model has been applied in many areas of the world, including North America (Lugo et al. 1999), Australia (Jia et al. 2012), and globally (Emanuel et al. 1985;Olson et al. 2001;Sisneros et al. 2011). Although not designed to be as detailed as more recently developed ecological classifications used in the US (e.g., Cleland et al. 1997;Comer et al. 2003;Omernik and Griffith 2014), the Holdridge system relies directly on simple climatic variables modeled by all GCMs, and in many ways, avoids the complex geologic, edaphic, and floristic components used by other classifications that are difficult to relate objectively to output from GCMs (Lugo et al. 1999). Moreover, the coarse resolution of the Holdridge system is consistent with the spatial, temporal, and predictive limitations of current climate models, and provides a more suitable framework for analyzing small-scale (large-area) phenomena, such as biome shifts or changes in the geographic range of a species. ...
... As expected, major life zones conformed to general temperature and precipitation gradients in the coterminous US that are determined by latitude, prevailing wind direction, major mountain ranges, and proximity to large sources of atmospheric moisture. Lugo et al. (1999) applied the Holdridge life zone system in the coterminous US using similar input data with a 4-km resolution, but only identified 38 life zones, 95% of which were in the western US. The eastern half of the country comprised almost entirely of two life zones: warmtemperate and cool temperate moist forests (Lugo et al. 1999). ...
Article
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Climate-change impacts to Department of Defense (DoD) installations will challenge military mission and natural resource stewardship efforts by increasing vulnerability to flooding, drought, altered fire regimes, and invasive species. We developed biome classifications based on current climate for the coterminous United States using the Holdridge Life Zone system to assess potential change on DoD lands. We validated classifications using comparisons to existing ecoregional classifications, the distribution of major forest types, and tree species in eastern North America. We projected future life zones for mid- and late-century time periods under three greenhouse gas emission scenarios (low—B1, moderate—A1B, and high—A2) using an ensemble of global climate models. To assess installation vulnerability (n = 529), we analyzed biome shifts using spatial cluster analysis to characterize interregional variation, and identified representative installations for subsequent landscape-level analyses. Although mean annual temperatures are expected to increase, installations located in the Northeast, Lake States, and western Great Plains are likely to experience the largest proportional increases in temperature. Accordingly, forest and grassland communities at these installations managed to support a wide range of training, and environmental objectives may be adversely affected by altered disturbance regimes, heat, and moisture stress. However, precipitation is projected to increase in the Northeast and Lake States mitigating some effects of increased temperatures on biological communities. Given the uncertain response to climate change in different ecoregions, additional environmental and stewardship attributes are needed within a decision-support framework to understand vulnerabilities and provide appropriate responses.
... A fundamental first step in designing an ecosystem management program is the delineation and classification of ecologically homogeneous units. The basic attributes of the system being managed could be derived from existing maps or classification schemes (Lugo et al. 1999). In particular, an efficient ecological zonation should be based on quantitative variables and be sensitive to changes in environmental factors affecting the development or the spatial distribution of ecosystems. ...
... Leslie R. Holdridge (1947Holdridge ( , 1967Holdridge ( , 1979) developed a model based on the characterization and mapping of bioclimatic units ( fig. 1). The model has an empirical and objective basis and defines the conditions for ecosystem function through its first-level ecological unit, the "life zone" (Lugo et al. 1999). The life zone concept According to Holdridge (1947), a life zone is a natural ensemble of associations defined by three variables that limit the development of biological processes and that can be expressed in a logarithmic scale to convey the influence of heat and water on biological responses. ...
... Holdridge's ecological model was applied mainly to the tropical and subtropical zones of the Americas: Perú (Tosi 1960), Honduras (Holdridge 1962a), Colombia (Espinal and Montenegro 1963), Venezuela (Ewel and Madriz 1968), Paraguay (Holdridge 1969), Costa Rica (Tosi 1969), Panamá (Tosi 1971), Puerto Rico (Ewel and Whitmore 1973), Bolivia (Unzueta 1975), Brasil (Tosi 1983, Tres 2016, and Nicaragua (Holdridge 1962b, Mendoza et al. 2001. It was also applied in the United States (Lugo et al. 1999), the People's Republic of China (Yue et al. 2001), Russia (Kirilenko and Salomon 1998, Krankina et al. 1997, Wieder et al. 2006, and India (Chakraborty et al. 2013). Furthermore, a low-detail worldwide map of life zones is available (IIASA 1989). ...
... An approach suggested for establishing reference benchmarks is the maximum value in the biodiversity or biocomplexity indicator observed, generally, in undisturbed stands (Terradas et al., 2004). Here, a regional model was used based upon Holdridge´s life zones (Lugo et al., 1999); which is equivalent to the forest stand concept, in order to calculate different benchmarks of forest development. Then, several forest stands are identified according to the landscape spatial heterogeneity in ecological conditions; i.e., variety of life zones where forest stands occur. ...
... The Holdridge´s classification of life zones relies on the identification of classification units that define conditions for ecosystem functioning. Life zones are delimited by biotemperature, precipitation, potential evapotranspiration ratio, and elevation (Chen et al., 2003;Khatun et al., 2013;Lugo et al., 1999;Villers-Ruíz and Trejo-Vázquez, 1998;Yue et al., 2001). Life zones are defined as "…a biogeographical zone, limited by climatic parameters, such as air temperature and pluvial precipitation, in which similar life forms will share the same characteristics" (Holdridge, 1967). ...
Article
This paper presents a conceptual framework for analyzing forest complexity as the combination of the variety of species and key structures that are associated with the composition, structure, and function of forest stands. Several spatial indicators have been developed to characterize the biodiversity, the structural complexity, and anthropogenic effects that can be observed in Mexican forests. By integrating several stand complexity attributes, the forest condition can be characterized as a function of species composition, stand structural attributes, and forest development. In addition, indicators of anthropogenic effects were also analyzed to identify their influence on forest eco-complexity, and therefore, on the current condition of forests. The results of applying this conceptual framework showed that Mexican forest are ecologically complex, with varying levels of anthropogenic impacts that modify the structural forest characteristics, particularly in tropical forests. The main factor explaining the current eco-complexity condition in tropical forests was associated with early stages of forest development, due to ecological degradation, and showed a generalized loss of attributes, particularly for stand complexity and stand development. In contrast, temperate forests exhibited better eco-complexity conditions, especially for those attributes that define forest stand occupancy and development. Mining activities, forest extraction as selective harvesting, forest fires, land use change, and road openings are critical human activities that directly affect forest structure and, ultimately, modify forest eco-complexity and integrity. This eco-complexity index derived for Mexican forests can be used to integrate measures of forest structure and functioning , and thereby better inform decision making and policy development.
... HE biological sciences have embraced visual mapping of ecosystems for a better understanding of dynamic processes and evolutions, as well as devising policies for their conservation. Highly cited articles in ecology point out several advantages of ecosystem visual mapping, such as the ability to predict vegetation patterns in ecosystems on the basis of mapped climate data as a driving force [1], the potential to investigate relationships and feedbacks in changing mangrove ecosystems [2], and the opportunity to reveal dynamic interrelationships between changes of human land use and ecosystem service capacity [3]. ...
... Tietze et al. [20] identify these early industrial efforts in the Crisis-Critical (CC-) Sector 3 in response to the COVID-19 induced health crisis as indicators of structural changes in industrial organisation and highlight resulting problems related to innovation governance and IP. Furthermore, they call for an IP focused analysis of the risks and uncertainties to key stakeholders during the different stages of the pandemic for the purpose of formulating appropriate 1 In this paper we adopt Tietze et al.'s [20] definition for Crisis-Critical (CC) Products, namely the aggregate of scarce products that are relevant to the prevention, diagnosis and treatment of patients during the COVID-19 Pandemic, such as vaccines, personal protective equipment, ventilators and diagnostic test kits. 2 Examples for these industrial efforts include GM and Ventec Life Systems jointly ramping up ventilator production [64], Dyson indigenously designing a innovation and IP policy responses [20]. In essence, visually mapping the rapidly evolving CC-Sector innovation ecosystem during the COVID-19 pandemic represents a highly appropriate testing environment for our new visual mapping method and particularly allows us to ascertain its efficacy in capturing IP related risks and uncertainties that accompany structural changes in industrial organisation. ...
Article
Prior management science literature proposes differ- ent visual methods for mapping ecosystems. These methods, how- ever, largely lack an effective approach to visualizing intellectual property (IP) related risks and uncertainties appearing among stakeholders as the innovation ecosystem evolves. Using the design science research methodology, we develop a novel method that visualizes loci of IP risks and uncertainties, as well as dynamics of IP ownership and usage in evolving innovation ecosystems. We demonstrate and evaluate the effectiveness of the new method in uncovering IP related risks and uncertainties by presenting results from applying the method to the innovation ecosystem for crisis-critical products during the COVID-19 pandemic. The currently ongoing pandemic has caused structural changes to that innovation ecosystem with new relationships being formed between incumbent manufacturers and new entrants that have rushed into that innovation ecosystem to support the upscaling of manufactur- ing capacities. This article contributes to the literature on visual methods for innovation ecosystems and provides a new method for researchers, practitioners, and policy makers to identify IP related risks and uncertainties that can arise when innovation ecosystems undergo structural changes. The method allows researchers to formulate and test new theories, as well as practitioners and policy makers to develop strategies to anticipate and mitigate IP risks and uncertainties.
... A series of models have been developed to simulate the spatial distributions of vegetation ecosystems [16], in which the dominant models include the Holdridge Life Zone ( HLZ) ecosystem model [9], the model of predicting physiognomic vegetation types with climate variables developed by Box E.O.(BOX) [17], Dynamic Global Phytogeography Model (DOLY) [8], Mapped Atmosphere-Plant Soil System (MAPSS) model [18] and Integrated BIosphere Simulator (IBIS) [19]. In particular, the HLZ ecosystem model has been widely used and is considered an effective method for simulating the potential distributions of vegetation ecosystems [20][21][22][23][24] because the model parameters only involve the three key climatic factors: Mean annual biotemperature (MAB), average total annual precipitation (TAP) and potential evapotranspiration ratio (PER) [25][26][27]. ...
... The HASM method [11,41,42] was utilized to obtain high-resolution and high-accuracy climate data by interpolating the station observational climate data and downscaling the climate scenario data. The HLZ ecosystem model [9], as a bioclimatic classification scheme [48], has been widely used to simulate the distributions of terrestrial ecosystems [35,36,49], predict land cover change [47], and support land use planning [20][21][22][23][24][25]. In this paper, the HLZ ecosystem model was improved to simulate the distribution of the potential vegetation type. ...
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Climate change dominantly controls the spatial distributions of potential vegetation ecosystems; the shift trends in the mean centers of potential vegetation ecosystems could be used to explain their responses to climate change. In terms of the climate observation data of Eurasia for the period from 1981 to 2010 and the climate scenario data for the period from 2011 to 2100 under the three Representative Concentration Pathways (RCPs) scenarios of RCP2.6, RCP4.5 and, RCP8.5, which were released by the Coupled Model Intercomparison Project Phase 5 (CMIP5), the Holdridge Life Zone (HLZ) ecosystem model was improved to quantitatively classify the potential vegetation types, and the shift model of mean center was adopted to compute the trends in the spatiotemporal shifts of potential vegetation types in Eurasia. The results showed that the mean centers of the major potential vegetation ecosystems would be distributed in the central and southern parts of Eurasia. Under the RCP2.6, RCP4.5, and RCP8.5 scenarios, the potential shift distances of the mean centers of the vegetation types under the RCP8.5 scenario would be the largest, and those of the polar/nival area, subpolar/alpine moist tundra, warm temperate dry forest, subtropical moist forest, cool temperate moist forest, cool temperate wet forest, subtropical wet forest, subtropical thorn woodland, warm temperate moist forest and subtropical dry forest would be larger than those in the other potential vegetation types in Eurasia. Moreover, the shift directions of the mean centers of the major potential vegetation types would generally shift northward, and subtropical dry forest, warm temperate moist forest and subpolar/alpine moist tundra would be the most sensitive to change among all vegetation types under the three scenarios for the period from 2011 to 2100.
... F I G U R E 5 Mean soil organic carbon (SOC) stocks (0-100 cm) and SOC storage (total per zone) plotted across the Holdridge scheme for world life-zone classification (upper triangles). Zones are sorted by biotemperature region (from top subpolar to bottom tropical) and humidity provinces (from super arid on the left to super humid on the right) (Cramer & Leemans, 1993;Harris, 1973;Lugo et al., 1999). Lower triangles present predicted changes in precipitation and temperature within the HLZ classes. ...
Article
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Soil organic carbon (SOC) holds the largest terrestrial carbon stock because of soil conditions and processes that favor soil carbon persistence. Vulnerable to climate change, SOC may cross a tipping point toward liberating carbon‐based greenhouse gases, implying massive self‐amplifying SOC‐ climate interactions. Estimates of SOC persistence are challenging as we still lack broad mechanistic insights. Upscaling mechanistic details from small to larger scales is challenging because the driving factors are not available at the needed resolution. Downscaling is problematic as many modeling studies point to the highest uncertainties deriving from the SOC response to climate change, while models themselves have difficulties in replicating contemporary soil properties and dynamics. To bridge the problems of scaling, strict process orientation seems adequate. Holdridge Life Zones (HLZ) classification, as one example, is a climate classification framework at a mesoscale that provides a descriptive approach to facilitate the identification of potential hotspots and coldspots of SOC‐climate interaction. Establishing coordinated experiments across all HLZ, but also including multiple global change drivers, has the potential to advance our understanding of general principles regulating SOC‐climate interaction and SOC persistence. Therefore, regionally tailored solutions for both experiments and modeling are urgently needed and can lead to better management of soil and the ecosystem services provided. Improving “translations” from the scales relevant for process understanding to the scales of decision‐making is key to good management and to predict the fate of our largest terrestrial carbon stock. This article is categorized under: Integrated Assessment of Climate Change > Integrated Scenario Development
... Climate information is implemented in the CWP by employing the Holdridge ecosystem classification concept based on the Holdridge life zones (HLZs; Holdridge, 1967), which provide a global classification of climatic zones in relation to potential vegetation cover. The HLZ concept is commonly used as a tool for ecosystem mapping from various overlapping research communities (Lugo et al., 1999;Yue et al., 2001;Khatun et al., 2013;Szelepcsényi et al., 2014;Tatli and Dalfes, 2021). This paper gives detailed documentation on the preparation of the PFT map -hereinafter referred to as "LANDMATE PFT"within the Helmholtz Institute for Climate Service Science (HICSS) project "Modelling human LAND surface Modifications and its feedbacks on local and regional cliMATE" (LANDMATE). ...
Article
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The concept of plant functional types (PFTs) is shown to be beneficial in representing the complexity of plant characteristics in land use and climate change studies using regional climate models (RCMs). By representing land use and land cover (LULC) as functional traits, responses and effects of specific plant communities can be directly coupled to the lowest atmospheric layers. To meet the requirements of RCMs for realistic LULC distribution, we developed a PFT dataset for Europe (LANDMATE PFT Version 1.0; http://doi.org/10.26050/WDCC/LM_PFT_LandCov_EUR2015_v1.0, Reinhart et al., 2021b). The dataset is based on the high-resolution European Space Agency Climate Change Initiative (ESA-CCI) land cover dataset and is further improved through the additional use of climate information. Within the LANDMATE – LAND surface Modifications and its feedbacks on local and regional cliMATE – PFT dataset, satellite-based LULC information and climate data are combined to create the representation of the diverse plant communities and their functions in the respective regional ecosystems while keeping the dataset most flexible for application in RCMs. Each LULC class of ESA-CCI is translated into PFT or PFT fractions including climate information by using the Holdridge life zone concept. Through consideration of regional climate data, the resulting PFT map for Europe is regionally customized. A thorough evaluation of the LANDMATE PFT dataset is done using a comprehensive ground truth database over the European continent. The assessment shows that the dominant LULC types, cropland and woodland, are well represented within the dataset, while uncertainties are found for some less represented LULC types. The LANDMATE PFT dataset provides a realistic, high-resolution LULC distribution for implementation in RCMs and is used as a basis for the Land Use and Climate Across Scales (LUCAS) Land Use Change (LUC) dataset which is available for use as LULC change input for RCM experiment set-ups focused on investigating LULC change impact.
... Bioclimate classification systems, such as the KG and Holdridge schemes (Lugo et al., 1999), have been used to map regions or even the entire globe. These maps have been created using observational (Kottek et al., 2006) as well as climate model data, the latter including CMIP5 (Rahimi et al., 2020) and CMIP6 climate models (Kim and Bae, 2021). ...
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Climate change is predicted to lead to major changes in terrestrial ecosystems. However, significant differences in climate model projections for given scenarios of greenhouse gas emissions, continue to hinder detailed assessment. Here we show, using a traditional Koppen-Geiger bioclimate classification system, that the latest CMIP6 Earth System Models actually agree very well on the fraction of the global land-surface that will undergo a significant change per degree of global warming. Data from historical and ssp585 model runs are used to create bioclimate maps at various degrees of global warming, and to investigate the performance of the ensemble mean when classifying climate data into discrete categories. Using a streamlined scheme with 13 classifications, global bioclimate classification maps at 2K and 4K of global warming above a 1901-1931 reference period are presented. These projections show large shifts in bioclimate distribution, with an almost exclusive change from colder, wetter bioclimates to hotter, dryer ones. Historical model run performance is assessed and examined by comparison with the bioclimatic classifications derived from the observed climate over the same time period. The fraction of the land experiencing a change in its bioclimatic class as a function of global warming is estimated by combining the results from the individual models. Despite the discrete nature of the bioclimatic classification scheme, we find only a weakly-saturating dependence of this fraction on global warming which implies about 12 pct of land experiencing a significant change in climate, per 1K increase in global mean temperature between the global warming levels of 1 and 3K. Therefore, we estimate that stabilising the climate at 1.5K rather than 2K of global warming, would save over 7 million square kilometres of land from a major bioclimatic change.
... Holdridge life zones are ecoregions classified by water availability and temperature that can be further subdivided into successional stages reflecting land use, disturbance history, latitude, altitude (Holdridge, 1967;Lugo et al., 1999). The parameters for each life zone are calculated based on potential evapotranspiration and humidity provinces (Holdridge, 1967; see Appendix D). ...
Article
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As atmospheric carbon dioxide (CO2) and temperatures increase with modern climate change, ancient hothouse periods become a focal point for understanding ecosystem function under similar conditions. The early Eocene exhibited high temperatures, high CO2 levels, and similar tectonic plate configuration as today, so it has been invoked as an analog to modern climate change. During the early Eocene, the greater Green River Basin (GGRB) of southwestern Wyoming was covered by an ancient hypersaline lake (Lake Gosiute; Green River Formation) and associated fluvial and floodplain systems (Wasatch and Bridger formations). The volcaniclastic Bridger Formation was deposited by an inland delta that drained from the northwest into freshwater Lake Gosiute and is known for its vast paleontological assemblages. Using this well-preserved basin deposited during a period of tectonic and paleoclimatic interest, we employ multiple proxies to study trends in provenance, parent material, weathering, and climate throughout 1 million years. The Blue Rim escarpment exposes approximately 100 m of the lower Bridger Formation, which includes plant and mammal fossils, solitary paleosol profiles, and organic remains suitable for geochemical analyses, as well as ash beds and volcaniclastic sandstone beds suitable for radioisotopic dating. New 40Ar / 39Ar ages from the middle and top of the Blue Rim escarpment constrain the age of its strata to ∼ 49.5–48.5 Myr ago during the “falling limb” of the early Eocene Climatic Optimum. We used several geochemical tools to study provenance and parent material in both the paleosols and the associated sediments and found no change in sediment input source despite significant variation in sedimentary facies and organic carbon burial. We also reconstructed environmental conditions, including temperature, precipitation (both from paleosols), and the isotopic composition of atmospheric CO2 from plants found in the floral assemblages. Results from paleosol-based reconstructions were compared to semi-co-temporal reconstructions made using leaf physiognomic techniques and marine proxies. The paleosol-based reconstructions (near the base of the section) of precipitation (608–1167 mm yr−1) and temperature (10.4 to 12.0 ∘C) were within error of, although lower than, those based on floral assemblages, which were stratigraphically higher in the section and represented a highly preserved event later in time. Geochemistry and detrital feldspar geochronology indicate a consistent provenance for Blue Rim sediments, sourcing predominantly from the Idaho paleoriver, which drained the active Challis volcanic field. Thus, because there was neither significant climatic change nor significant provenance change, variation in sedimentary facies and organic carbon burial likely reflected localized geomorphic controls and the relative height of the water table. The ecosystem can be characterized as a wet, subtropical-like forest (i.e., paratropical) throughout the interval based upon the floral humidity province and Holdridge life zone schemes. Given the mid-paleolatitude position of the Blue Rim escarpment, those results are consistent with marine proxies that indicate that globally warm climatic conditions continued beyond the peak warm conditions of the early Eocene Climatic Optimum. The reconstructed atmospheric δ13C value (−5.3 ‰ to −5.8 ‰) closely matches the independently reconstructed value from marine microfossils (−5.4 ‰), which provides confidence in this reconstruction. Likewise, the isotopic composition reconstructed matches the mantle most closely (−5.4 ‰), agreeing with other postulations that warming was maintained by volcanic outgassing rather than a much more isotopically depleted source, such as methane hydrates.
... The highest monthly mean daily max temperature (July) is 32.0°C, and the lowest monthly mean daily low temperature (January) is 11.1°C (NOAA-NCDC). Spartina alterniflora (smooth cordgrass) and A. germinans (black mangrove) are common at both sites although Avicennia trees are generally larger and more abundant at SS. Spartina is a C 4 grass (PEP-CK subtype) that dominates temperate estuaries along the east coast of North America and warm-temperate estuaries in the Gulf of Mexico and northern Florida (Lugo et al., 1999). Avicennia is a broadly distributed mangrove species native to warm-temperate, subtropical, and tropical regions of the Americas and Africa. ...
Article
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Temperature acclimation of leaf respiration (R) is an important determinant of ecosystem responses to temperature and the magnitude of temperature-CO2 feedbacks as climate warms. Yet, the extent to which temperature acclimation of R exhibits a common pattern across different growth conditions, ecosystems, and plant functional types remains unclear. Here, we measured the short-term temperature response of R at six timepoints over a 10-month period in two coastal wetland species (Avicennia germinans (C3 mangrove), Spartina alterniflora (C4 marsh grass)) growing under ambient and experimentally warmed temperatures at two sites in a marsh-mangrove ecotone. Leaf nitrogen (N) was determined on a subsample of leaves to explore potential coupling of R and N. We hypothesized that both species would reduce R at 25 °C (R²⁵) and the short-term temperature sensitivity of R (Q10) as air temperature (Tair) increased across seasons, but the decline would be stronger in Avicennia than Spartina. For each species, we hypothesized that seasonal temperature acclimation of R would be equivalent in plants grown under ambient and warmed temperatures, demonstrating convergent acclimation. Surprisingly, Avicennia generally increased R²⁵ with increasing growth temperature, although the Q10 declined as seasonal temperatures increased and did so consistently across sites and treatments. Weak temperature acclimation resulted in reduced homeostasis of R in Avicennia. Spartina reduced R²⁵ and the Q10 as seasonal temperatures increased. In Spartina, seasonal temperature acclimation was largely consistent across sites and treatments resulting in greater respiratory homeostasis. We conclude that co-occurring coastal wetland species may show contrasting patterns of respiratory temperature acclimation. Nonetheless, leaf N scaled positively with R²⁵ in both species highlighting the importance of leaf N in predicting respiratory capacity across a range of growth temperatures. Patterns of respiratory temperature acclimation shown here may improve predictions of temperature controls of CO2 fluxes in coastal wetlands.
... Nevertheless, the concept was and is globally still widely applied (e.g. Khatun et al., 2013;Lugo et al., 1999) due to the direct biogeographical link of forest ecosystems and climate variables such as temperature and precipitation. The latter link makes climate change projections feasible and work on such HLZ projections go back to, for example, Emanuel et al. (1985). ...
Article
Efforts to protect tropical ecosystems aim at implementing biological corridors across the national territory of Costa Rica. However, potential near-future climate change challenges the effectiveness of such conservation measures. For this purpose, we developed near-future climate change scenarios at high spatial resolution using open-access global data from the Copernicus Climate Data Store (CDS). These projections resulted from downscaling (to a 1km ² national grid) and quantile-mapping bias-correction of the Essential Climate Variables Global Circulation Model (ECV_GCM) ensemble mean from the CDS using a moderate Representative Concentration Pathway 4.5 (RCP4.5). Projections were evaluated with limited local station data and applied to generate future ecosystem indicators (Holdridge Life Zones, HLZs). We show significantly increasing temperatures of 2.6°C with a spatial variability of ± 0.4°C for Costa Rica until 2040 with local differences (higher temperatures projected for the southern Costa Rican Caribbean). The future mean annual precipitation showed slightly wetter conditions (120 ± 43 mm/year) and most prominently in the Costa Rican Caribbean and south Pacific, but no significant drying in the north of Costa Rica by 2040. The bias-corrected climate data were aggregated to decadal and 30-year average (1971–2040) life zone ecosystem indicators that could potentially show ecosystem shifts. Changes in the life zones are most likely due to warmer temperatures and to a lesser extent caused by projected wetter conditions. Shifts are more likely to occur at higher elevations with a potential loss of the sub-tropical rainforest ecosystem. The projections support diminishing tropical dry forests and slightly increasing tropical rain and wet forests in the biological corridors of the driest and wettest regions, respectively. A countrywide spatial uniformity of dominating tropical moist forests (increase from 24% to 49%) at the expense of other HLZs was projected by 2040.
... for lateral continuity ( Figure D1) (Retallack, 1991; Holdridge life zones provide a semi-quantitative means of matching climate with vegetation and provide the underpinnings for other modern approaches to soil energy models (Holdridge, 1947;Lugo et al., 1999). Data for Holdridge calculations can be found in Table D4. ...
Thesis
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The co-evolution of the terrestrial biogeochemical cycle, the atmosphere, and the marine biosphere remain relatively poorly understood, with outstanding questions surrounding terrestrial-marine links, climate, and tectonics. In particular, the terrestrial sediment source (i.e., soils) remains understudied relative to the marine sediment sink, with the source essentially defined by the record in the sediment sink rather than being considered equally important. Both the sediment source and sink need to be well-constrained in order to understand global biogeochemical changes. Additionally, interpretations of trends in paleosol (fossil soil) geochemistry are only loosely constrained by large-scale modern soil chemical variability, limiting our ability to assess potential changes in biogeochemical cycling through time. This dissertation focused on two primary goals: improving quantitative constraints on terrestrial biogeochemical cycling and weathering over geologic time, and improving our ability to accurately interpret those records by understanding both modern context and what the paleosol record actually represents. To address these goals, I analyzed the geochemical composition of soils and paleosols (fossil soils) over the past three billion years. Because soils form in the ‘critical zone’—the intersection of the biosphere, geosphere, and atmosphere at Earth’s surface—they record surficial conditions more directly than other geologic records, providing valuable insight into past climates, atmospheres, and ecosystems. After providing generalized, quantitative constraints on geochemical and weathering variability in modern soils (Chapter II), I used the paleosol record to test for state changes in soil P (Chapter III) and weathering intensity (Chapter IV) on land during key biogeochemical transitions. I also explored a variety of processes that could bias the distribution of paleosols through space and time (e.g., preservation, sampling), which needs to be better constrained in order to interpret paleosols accurately. In modern soils, I found weaker than expected relationships between soil P and Fe geochemistry and key environmental factors (climate, vegetation, parent material), but weathering intensity, the presence of vegetation, and P concentrations were related. The weak relationships could be due to the continental rather than localized scale of analysis. While the latter might have provided predictive relationships between soil chemistry and soil-forming factors, a highly-localized scale is often not considered in deep-time biogeochemical modeling. In paleosols, I found that both the P composition and weathering intensity have been stable through time. Discrete, state changes in P composition or weathering intensity—as have been hypothesized based upon marine records—were not recorded. A discrete change was present in the concentration of Ca in paleosols, which increased in the Phanerozoic, perhaps reflecting a shift in pedogenic processes as vascular, rooting plants evolved. Roots and vascularity allowed plants to colonize more arid environments and facilitated the formation of pedogenic carbonate—an important C sink. Therefore, while the advent of land plants may not have led to a global state change in either terrestrial P retention or weathering intensity, plants facilitated the growth of the soil C sink. Because weathering intensity is consistent through time, other factors (e.g., land area, erosion rates) would have been dominant controls on marine nutrient supply through time, with shorter-term perturbations in weathering intensity occurring before returning to the stable baseline. Finally, the distribution of paleosols through time is uneven, with more paleosols being more common (a) towards the present and (b) during peaks in zircon ages, suggesting a formation and/or preservation bias related to the supercontinent cycle.
... Holdridge life zones provide a semi-quantitative means of matching climate with vegetation and provide the underpinnings for other modern approaches to soil energy models (Holdridge, 1947;Lugo et al., 1999). Mean annual precipitation and the ratio of estimated evapotranspiration to MAP (ET/MAP) are plotted on a ternary diagram, with classes (as defined by the International Institute for Applied Systems Analysis) overlaid based on modern vegetation maps. ...
Article
Paleosols (fossil soils) are valuable records of terrestrial climate and environments, and paleosol-based proxies are commonly used to reconstruct past climates and ecosystems. Results from relatively small outcrops or transects or from single vertical sections are frequently scaled up to represent basin-scale processes and conditions, and reconstructions are relied on for temporal changes in those basins. However, uncertainty arising from limited outcrop extent is not currently considered in the standard application of paleosol-based proxies. To explore uncertainty arising from lateral paleosol heterogeneity, we performed a random subsampling analysis on a newly-collected 2.9 km paleosol transect from SW Wyoming, along with two previously-published paleosols. We demonstrate the importance of sampling multiple paleosol profiles, considering lateral geochemical variability, and focusing on relative rather than absolute changes when outcrop-based uncertainty may require it.
... The upper Rio Grande Valley in Northern New Mexico is defined as a semi-arid environment [3,4] and so is at high risk of water shortages for agricultural and domestic use in the present and future. Northern New Mexico derives 98.8% of its surface water from snowpack melt from the San Juan Mountain Range in Southern Colorado [5,6], but decreasing trends in snow depth and snow cover threaten water security in the Western United States [7]. ...
Article
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Commercial and landrace chile (Capsicum annuum) cultivars are cultivated under furrow irrigation systems in Northern New Mexico. Yield and physiological differences between commercial and landrace chile cultivars under furrow irrigation systems have not been evaluated. In 2011 and 2012 two commercial chiles, ‘Sandia’ and ‘NuMex Big Jim’, with one landrace chile, ‘Chimayo’, were evaluated under four irrigation schedules, with irrigation once every 7, 9, 11, and 13-days. These four schedules represent possible water availability for farmers in Northern New Mexico. In 2011 there were inconsistent yield patterns; fresh red chile yield of ‘Chimayo’ at the seven-day interval was 90% more than at the nine-day interval. ‘Sandia’ had 138% better yields at the seven- than at the nine-day interval. ‘Chimayo’ fresh green chile yields at the nine-day interval were 47% better than the seven-day interval. ‘NuMex Big Jim’ fresh green yields were 40% greater at the seven-day interval than the 13-day interval. In 2012 no yield components were statistically different for cultivars across irrigation intervals. This data shows commercial green and landrace chile cultivars can be furrow irrigated as water becomes available on 7, 9, 11, or 13-day intervals with no yield effect.
... The Köppen classification is also employed in the delineation of Bailey's US ecoregions [14]. Another bioclimatic scheme, called the Holdridge life zone system, was proposed by Holdridge in 1947 [15,16], initially for tropical regions and later extended to boreal and temperate zones [17]. These bioclimatic classification schemes served as a scientific basis and inspiration for modern developments, including climate envelope models (CEMs), species distribution models (SDMs), and dynamic global vegetation models (DGVMs), within Earth system models (ESMs), focusing on both the understanding of vegetation formations and the prediction of climate effects across various temporal and spatial scales [18,19]. ...
Article
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A predictive understanding of interactions between vegetation and climate has been a grand challenge in terrestrial ecology for over 200 years. Developed in recent decades, continental-scale monitoring of climate and forest dynamics enables quantitative examination of vegetation–climate relationships through a data-driven paradigm. Here, we apply a data-intensive approach to investigate forest–climate interactions across the conterminous USA. We apply multivariate statistical methods (stepwise regression, principal component analysis) including machine learning to infer significant climatic drivers of standing forest basal area. We focus our analysis on the ecoregional scale. For most ecoregions analyzed, both stepwise regression and random forests indicate that factors related to precipitation are the most significant predictors of forest basal area. In almost half of US ecoregions, precipitation of the coldest quarter is the single most important driver of basal area. The demonstrated data-driven approach may be used to inform forest-climate envelope modeling and the forecasting of large-scale forest dynamics under climate change scenarios. These results have important implications for climate, biodiversity, industrial forestry, and indigenous communities in a changing world.
... Haplotype networks of the EFC-UNA collection were constructed with PopART (http://popart.otago.ac.nz) using the concatenated alignment and the TCS inference method (Clement et al., 2002). The Holdridge life zone system for ecosystem mapping (Holdridge, 1967;Lugo et al., 1999) was used as a grouping criterion, and life zones were considered as an abiotic factor for grouping isolates. Geographical coordinates were used to assign life zones for each isolate using the QGIS software (Geographic Information System. ...
Article
The genus Beauveria comprises economically important entomopathogenic fungi, widely used for biological control in agriculture. Interest in these organisms in Costa Rica prompted surveys and establishment of collections in the past two decades. However, there was neither a formal identification nor a characterization of the isolates. With that purpose, the morphology and genetic variation by microsatellites and partial sequencing of Bloc, TEF-1α and RPB2 regions were studied for 32 isolates of Beauveria, which included 26 from Costa Rica, five from Puerto Rico and one from Honduras. The isolates were identified as B. bassiana (29) and B. caledonica (3). Ninety-three percent of B. bassiana isolates belonged to a monophyletic group of African and Neotropical isolates. A total of 105 alleles were recorded with 11 SSR markers, and the results suggested high diversity within the collection. Mantel tests showed low association between geographic origin and the variation among isolates.
... There are significant limitations with the Holdridge forest classification system (Peng, 2000). A major limitation with using broad zonal vegetation models such as the Holdridge Forest Classification system is that they consider all species to be influenced homogenously by climate and that species composition within the biomes will remain constant under changing climatic conditions and migrate as one unit (Davis et al., 1998;Lugo et al., 1999;Peng, 2000). Terrestrial ecosystems are, however, composed of many species which respond individually to changing environmental conditions rather than moving in concert. ...
Article
Rural communities in the Himalayan Kingdom of Bhutan are dependant on natural capital for their livelihoods. Climate change impacts on ecosystem could have serious consequences for these communities but little research has been done to explore these potential impacts. In this study, we used Boosted Regression Tree (BRT) models to model current and potential future distribution of major timber species (Abies densa, Pinus wallichiana, Tsuga dumosa), fuelwood species (Quercus spp, Betula spp, Betula utilis, Rhododendron spp, Rhododendron arboreum) and an important non-timber resource (Ophiocordyceps sinensis) in Bhutan Himalayan region. Models were based on species presence and absence data from 575 plots and a new high-resolution climate dataset developed for Bhutan. Future projections were based on IPCC's representative concentration pathway (RCP 8.5) for the 2080s in Bhutan. Mean annual temperature and precipitation of driest quarters were found to be the most influential variables in modelling the current distribution of these species, with the distribution of most of the species projected to decrease significantly and shift to higher elevations. The current distribution of Ophiocordyceps sinensis was modelled to decrease by 79% at the national level with only 21% range overlap between current and future distributions. Current distribution of timber species like Abies densa and Tsuga dumosa were modelled to decline by 98% and 99% respectively at national level with very low range overlaps between current and future distribution suggesting high species vulnerability to climate change. In contrast, fuel wood species like Betula spp, Quercus spp, Rhododendron arboreum all exhibited less vulnerability to climate change with over 50% of their current range overlapping with future distribution across Bhutan and in the Nikachu watershed. These potential changes in distribution patterns of these species could impact on the functions and ecosystem services provided by these species and socio-economic conditions of rural communities reliant on these species for their livelihoods in Bhutan. Lower rates of global greenhouse gas emissions and adoption of adaptation measures and management interventions can reduce these potential impacts.
... Coral reef habitats at the northern extent of Florida's coral reef tract are of particular concern, residing at their latitudinal environmental limits while also increasingly exposed to global and local anthropogenic stressors including land-based sources of pollution (e.g., freshwater runoff, sedimentation), annual temperature flux, and warming sea temperatures (Lirman and Fong, 2007;Gregg, 2013). Within this region, coral reefs inhabit an ecotone transition between subtropical and warm temperate climate zones (Lugo et al., 1999). Reefs in southeast Florida face high levels of both seasonal and episodic environmental variation that combine with anthropogenic impacts to impose multiple stressors on scleractinian corals. ...
Article
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Coral reefs at the northern extent of Florida’s coral reef tract are exposed to many localized anthropogenic influences including controlled freshwater discharges, runoff, upwelling, and seasonal environmental variability. To better understand coral responses to sublethal stressors in nearshore environments, we conducted complementary experiments to assess the impacts of estuarine runoff and temperature stress on local populations of the scleractinian coral species, Montastraea cavernosa, using Tag-Seq global gene expression profiling. In an in situ time series experiment, fate-tracked colonies were sampled during periods of relatively low and high estuarine discharge over 4 years to investigate temporal trends in transcriptional patterns and to identify if coral stress indicators were regulated through time. There was significant transcriptomic variation through time, but patterns did not appear to be attributed to distance from nearby estuarine tidal flux. In an ex situ factorial experiment, clonal replicates of coral genotypes were exposed to temperature (25°C and 30°C) and water (offshore and estuarine discharge, representing typical oceanic conditions and episodic discharge conditions, respectively) treatments to quantify the potential individual and synergistic effects of sublethal stress on coral and algal gene expression. Comparative analyses suggested that corals and their algal symbionts were more responsive to thermal stress than to estuarine discharge, although there was evidence of a synergistic relationship between the two stressors. Strong genotype effects also demonstrated that transcriptomic responses to thermal stress were largely based on coral genotype, indicating the potential for stress resilience among certain members of coral populations from southeast Florida.
... Cape-ivy has invaded the entire length of the California coastline, an area that spans a wide range of temperatures (10.5 to 17.7 • C annual average) and precipitation levels (23 to 230 cm, annual total from south to north; Robison and DiTomaso, 2010;Lund, 2016). Dry season (typically April to October) wilting of Cape-ivy shoots is common in open, unshaded habitats, indicative of the plant's ability to tolerate water deficit stress during seasonal and climatic drought in California's Mediterranean (Lugo, 1999) climate. The quantity and quality of Cape-ivy shoot tips are expected to affect the likelihood of establishment and initial population growth of P. regalis. ...
Article
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Drought leading to water deficit stress is known to reduce performance of galling insects. The shoot tip-galling fly Parafreutreta regalis has been released for biological control of Cape-ivy (Delairea odorata) in California. Lack of moisture during the dry season causes wilting of Cape-ivy shoots, and subsequent reduced host quantity and quality could influence the fly’s ability to multiply and establish. We imposed water deficit stress on potted Cape-ivy plants, then measured the plant’s and insect’s response to water deficit compared to fully-watered plants. Water deficit stress was imposed during female oviposition (short-term), gall development (long-term), or full insect life cycle (long-term). Plants subjected to long-term water deficit showed declines in shoot growth, leaf area, and total biomass. In choice tests, 72% fewer galls were found on water deficit stressed plants, but there was no difference in the numbers of insects per gall. In no-choice tests, long-term water deficit reduced the number and size of galls by up to 51% and 39%, respectively, and puparia inside the galls were up to 35% smaller. Long-term water deficit also increased the time required for the insect to complete its life cycle (egg to adult) by about 10 days, and up to 80% fewer adults emerged, decreasing the fly’s rate of increase by up to five-fold. Our study shows that P. regalis will oviposit and develop successfully on water deficit-stressed plants, but declines in female preference, insect development and abundance could inhibit fly field establishment and/or population growth under climatic drought conditions.
... All sites are classified as 'warm temperate dry' (Lugo et al. 1999) with a Mediterranean climate of warm, dry summers and cool, wet winters. Most precipitation occurs between November and April, predominantly as rain at low elevation sites (e.g., Challenge) and snow and rain at higher elevation sites (e.g., Owl). ...
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Soil resilience following harvest disturbance was studied at nine Long-Term Soil Productivity sites across the Sierra Nevada mountain range of California. We tested whether soil compaction, surface organic matter (OM) retention, and plant diversity have lasting effects on soil C, N, bulk density, or porosity. Study treatments following clearcut harvesting included soil compaction (none, moderate, severe) in factorial combination with three levels of OM retention (harvest slash retained, [OM2]; no slash retained, [OM1]; bare soil, [OM0]) and two plant diversity treatments (trees only; trees and shrubs). The sites encompassed a wide range in soil OM (5 to 12%) and clay content (5 to 36%) and represented common soil types in Sierran forests. At year 10, soil bulk densities were 10–29% greater for severely compacted compared to non-compacted plots across sites, corresponding to an average loss of 9–11% total porosity. Partial recovery was found by year 20, as bulk densities were 2–17% higher for compacted compared to non-compacted plots. In contrast to these physical responses, compaction had no adverse effect on soil C and N content at either year 10 or 20. Slash retention (OM2 versus OM1) and plant diversity treatments also had few effects on soil properties with the exception of a small increase in bulk density in the absence of shrubs, presumably due to reduced root and surface litter input. A more pronounced response was found following complete removal of surface organics (OM0), which produced a study-wide decline (12–17%) in soil C, N, and bulk density by year 20. All treatment responses were fairly consistent across sites, regardless of site differences in clay or soil OM content. Our results suggest substantial tolerance of soil C and N to harvest disturbance in Sierra Nevada forests despite a sustained change in soil physical properties and highlight the importance of the O horizon to long-term soil health.
... Holdridge's life zone system it is classified as subtropical moist forest life zone (Lugo et al., 1999) with mean annual precipitation ranging from 1509 mm on the coast to 1755 mm on more elevated areas, and a mean annual air temperature of 25.7 o C . It has been estimated that 72% of all rainfall results in high runoff (Osterkamp, 2001) from volcanic rocks and impervious surfaces Ramírez et al., 2014). ...
Thesis
Residential green spaces are increasingly gaining attention for their potential to contribute to ecosystem services of social and ecological value for cities. This research evaluated the potential of residential yards of San Juan, Puerto Rico, to contribute to urban sustainability through the provision of ecosystem services using a social-ecological approach. The study builds upon prior work at this site led by the San Juan Urban Long Term Research Area (ULTRA) Collaborative Network and addressed the following overarching question: Which social-ecological factors could be influencing the vegetation structure and composition of the Río Piedras Watershed residential yards and their associated ecosystem services and disservices across the watershed? The work combines social and ecological data collected from household and yard surveys following ULTRA’s long-term stratified sampling scheme of households via a convenient-based recruitment. Household surveys used semi-structured questionnaires implemented in 2011 and 2014 evaluated resident values and attitudes towards residential vegetation and their associated ecosystem services and how these may influence the structure and composition of yard vegetation across the watershed. This study took advantage of vegetation surveys implemented before and after the 2017 hurricane season to evaluate the influence of hurricane disturbances on yard vegetation. Main findings highlight that self-reporting of resident attitudes toward yard trees are generally positive with residents emphasizing ecosystem services over disservices, and varied according to differences in the spatial context of trees and residents. Models show that positive attitudes at the household scale may explain some of the variation in the number of yard trees. Residents also self-reported positive attitudes towards native plants mainly driven by sense of place, and expressed preference towards certain plant traits (i.e., habit, size) and ecosystem services. Findings also show that large-scale hurricane disturbances can have immediate effects on yard vegetation structure and composition and be an important driver of the provision of ecosystem services in addition to the stated social factors. In this work it is argued that understanding how social and ecological factors interact locally to influence yard vegetation provides a better idea of what elements of the vegetation may provide functions of local value and promote sustainability.
... aegypti-borne pathogen outbreak. The CONUS represents a unique environment for control: the country includes multiple climatic and ecological zones (Daubenmire 1938, Fovell and Fovell 1993, Lugo et al. 1999 as well as variability in housing conditions and local cultures (Reiter et al. 2003, Hayden et al. 2010, Hotez 2011. For this reason, experimental results from other countries may not sufficiently model similar experimental applications within the CONUS. ...
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Aedes aegypti (L) is an anthropophilic mosquito involved in the transmission of a variety of viral pathogens worldwide including dengue, chikungunya, yellow fever, and Zika viruses. This species, native to Africa, is well established in the continental U.S. (CONUS) and occasionally contributes to localized outbreaks of viral diseases. In the last seven decades, mosquito control programs in the CONUS have been focused on vectors of eastern equine encephalitis, St. Louis encephalitis, and West Nile viruses, as well as nuisance species. Aedes aegypti receives little control focus except during outbreak periods, which has led to a lack of information on appropriate and effective control options targeting Ae. aegypti in the CONUS. As such, in the event of an Ae. aegypti-borne arboviral outbreak in the CONUS, there are limited evidence-based control recommendations or protocols in place. Autochthonous outbreaks of Ae. aegypti-borne pathogens have occurred recently in the CONUS, including dengue outbreaks in 2010 and 2013, a chikungunya outbreak in 2014, and the 2016 outbreak of Zika virus. The increasing frequency of Ae. aegypti-borne outbreaks necessitates increased attention and research on control of this species to prevent and mitigate future outbreaks. This review consolidates and synthesizes the available literature on control of Ae. aegypti, specifically within the CONUS, focusing on data generated through operational applications as well as field and semifield experiments. The purpose of this review is to identify and highlight areas where additional research is needed. The review covers chemical control and insecticide resistance, biological control, source reduction, trapping, and alternative techniques.
... In the most comprehensive transitions (e.g., from forest to savanna; Silva 2014), many of the species typical of the former community or ecosystem are no longer present in the new system. Such whole-community transformations can be rapid, occurring when: (a) contemporary climate change shifts a landscape into a new biome (Lugo et al. 1999;Nolan et al. 2018), (b) invasive species, biogeochemical alterations, or severe disturbances (natural or anthropogenic) transform the ecosystem to a novel state (Scheffer et al. 1993;Hobbs et al. 2009Hobbs et al. , 2014, or (c) when successional trajectories following disturbances are redirected by environmental changes to new, self-sustaining states (Johnstone et al. 2016;Guiterman et al. 2018;Davis et al. 2019). ...
Article
Ecosystem transformation can be defined as the emergence of a self‐organizing, self‐sustaining, ecological or social–ecological system that deviates from prior ecosystem structure and function. These transformations are occurring across the globe; consequently, a static view of ecosystem processes is likely no longer sufficient for managing fish, wildlife, and other species. We present a framework that encompasses three strategies for fish and wildlife managers dealing with ecosystems vulnerable to transformation. Specifically, managers can resist change and strive to maintain existing ecosystem composition, structure and function; accept transformation when it is not feasible to resist change or when changes are deemed socially acceptable; or direct change to a future ecosystem configuration that would yield desirable outcomes. Choice of a particular option likely hinges on anticipating future change, while also acknowledging that temporal and spatial scales, recent history and current state of the system, and magnitude of change can factor into the decision. This suite of management strategies can be implemented using a structured approach of learning and adapting as ecosystems change.
... The species is only known from the Northern Marañón seasonally dry tropical forests (bosques tropicales estacionalmente secos, BTES Marañón Norte) characterized by precipitation below 1600 mm and an extended dry season (Pennington et al. 2000) (see distribution map, Fig. 4). Furthermore, the localities for the species reside within one of the six different kinds of dry forests recorded from Peru (Lugo et al. 1999), the "bosque muy seco tropical" (extremely dry tropical forests) or BMS-T (Linares-Palomino 2003). In these ecosystems, E. rhizomatosa grows as an epiphyte on canopy trees such as Celtis loxensis C.C.Berg (Cannabiaceae) and Aspidosperma polyneuron Müll.Arg. ...
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The identity of Epidendrum sclerocladium, currently referable to Encyclia, is clarified with the recent collection of material unambiguously referable to this entity. In addition, we provide a new name in Encyclia for this taxon, E. rhizomatosa Tamayo-Cen, Carnevali & G.A.Romero, because the current combination, E. sclerocladia (Lindl. ex Rchb.f.) Hoehne, is based upon the later homonym Epidendrum sclerocladium Lindl. ex Rchb.f. This name is predated by Epidendrum sclerocladium Lindley as we argue that Lindley validly published the name in a horticultural catalogue, a nomenclatural issue herein discussed. Furthermore, because the vegetative portions of the plants were unknown until recently, we provide an epitype to supplement the holotype for the unequivocal identification of the species. A preliminary assessment of its conservation status and phylogenetic relationships are presented. Encyclia thrombodes is discussed and it is concluded that no known plants are referable to this entity at this time. A lectotype is proposed for Epidendrum cyperifolium because the holotype was destroyed. Finally, we provide an annotated checklist of the Encyclia species known to occur in Peru.
... Global climate models do not recognize the diversity of climatic conditions in the tropics as revealed by the Holdridge Life Zone System (Holdridge, 1947). The Holdridge system depicts climate in general, and that of the tropics and subtropics in particular, with greater geographic precision and repeatability than the K€ oppen-Trewartha system (Lugo et al., 1999a). The application of the system is limited by the availability of empirical climate data, which the K€ oppen-Trewartha system was designed to overcome (Bailey, 2009). ...
... Global climate-classification systems aim to identify distinct climate types and map their geographical extents (Köppen, 2011;Lugo, Brown, Dodson, Smith, & Shugart, 1999). Condensing a multitude of local climates into a manageable number of climate categories would enable robust comparisons and ease of interpretation. ...
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Crop breeding is as ancient as the invention of cultivation. In essence, the objective of crop breeding is to improve plant fitness under human cultivation conditions, making crops more productive while maintaining consistency in life cycle and quality. Predictive breeding has been demonstrated in the agricultural industry and in public breeding programs for over a decade. The massive stores of data that have been generated by industry, farmers, and scholars through several decades have finally been recognized as a potential asset that can be brought to bear on specific breeding decisions. A wide range of analytical methods that were initially developed for various other quantitative disciplines, such as machine learning, deep learning, and artificial intelligence, are now being adapted for application in crop breeding to support analytics and decision making processes. This convergence between data science and crop breeding analytics is expected to address long‐standing gaps in crop breeding analytics, and realize the potential of applying advanced analytics to multidimensional data such as geospatial variables, a multitude of phenotypic responses, and genetic information. Here, we summarize the few existing examples followed by perspectives on where else these technologies would have applications to accelerate operational aspects of crop breeding and agricultural product development efforts.
... Global climate models do not recognize the diversity of climatic conditions in the tropics as revealed by the Holdridge Life Zone System (Holdridge, 1947). The Holdridge system depicts climate in general, and that of the tropics and subtropics in particular, with greater geographic precision and repeatability than the K€ oppen-Trewartha system (Lugo et al., 1999a). The application of the system is limited by the availability of empirical climate data, which the K€ oppen-Trewartha system was designed to overcome (Bailey, 2009). ...
Chapter
We review literature relevant to assessing the future of tropical forests and supplement the review with new data from the lowlands of Venezuela. Compared to today, future tropical forests will have a higher level of novelty, defined as the degree of dissimilarity of a system relative to a historical baseline. Processes of succession and evolution generate novelty in forests and have done so for millennia. Under increasing human activity and climate change, the rate of generation of novelty has increased and the resulting forests are termed novel forests to distinguish them from historical forests. Historical forests are less exposed to anthropogenic disturbances and operate at slower levels of novelty generation. Acclimation, adaptation, changes in species composition and dominance, and changes in the proportions of species in communities are the responses of the biota to climate change and anthropogenic disturbances. Therefore, novelty contributes to the persistence of tropical forests in spite of increasing levels of human activity. Novel forests are similar to historical forests in terms of structure but they are younger, they have a faster turnover of mass and chemical elements, and different species composition. Historical species assemblages cannot cope with the altered environments that result from chronic anthropogenic disturbances. The dominant species in novel forests tend to be, and function as, pioneer species. High levels of species dominance in novel forests influence the proportions of chemical elements, which when coupled to species traits and attributes, help explain how novel forests cope with the conditions that result from anthropogenic activities. Novelty is more common in the tropics than in other latitudinal regions, and within the tropics, it is more common in islands where human activity is more intense than in continents. Novel tropical forests in islands have greater representation and dominance of introduced species than novel forests in continents, where native species with wide geographic distributions dominate. Regardless of geography, novel tropical forests share similar attributes and functioning. The adaptability of novel forests to extreme conditions created by human activity signals a future for tropical forests that is different from predictions of constant degradation, homogenization, and loss of biodiversity. Instead, a process of recombination of species (all taxa) into new species assemblages maintains structure, function, physiognomy, species richness, and ecological services. This remixing initially involves loss of large organisms, certain groups of species, and loss of old-growth attributes of forests. Some of these losses can be reversed through succession, assuming there is sufficient time to restore depleted stores such as soil organic matter. Continued environmental change will stimulate continued remixing of species, loss of vulnerable species, gains of less vulnerable ones, and more dissimilarity with historical forests. Novel forests are an answer to the changes induced by climate change and other anthropogenic disturbances, and as such require conservation measures, because as they mature, novel forests usually diversify and help restore lost biodiversity. We also review strategies to conserve biodiversity and optimize ecological services using novel forest succession.
... The fallowing climate indices were evaluated:Johansson Continentality Index (Baltas, 2007), KernerOceanity Index (Baltas, 2007), Kira's Warmth Index (Hugget&Cheesman, 2002), Holdridge Annual Biotemperature ( Lugo et al., 1999). ...
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During the first decade of the XXI st century Danube Delta coast had a warming trend. The mean warming of the average of Sulina stations was 1.0°C for the decade, a large value for a decade. The warming trend of spring and autumn was positively correlated with the change of growing season length. The start of the growing season has advanced with 11 days, the end of the growing season has delayed with 13 days, and the growing season length was 269.7 days.
... Since 2001, Guntersville Reservoir, a dammed portion of the Tennessee River in Alabama, has had cormorants breeding on islands throughout the reservoir. A study by Lafferty et al. (2016) investigated how breeding cormorants affect these warm temperate moist forest ecosystems (Lugo et al., 1999), and found that cormorants deposit P, potassium (K) and T nitrate (NO 3 − ) on their nesting islands while also decreasing pH and damaging tree health (Lafferty et al., 2016). However, Lafferty et al. (2016) did not look at vegetation structure such as midstory height, plant and avian diversity or plant and avian community structure on islands, nor islands abandoned by cormorants over historical time periods. ...
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This data article provides the methods and procedures followed to collect and analyse soil, vegetation and bird data on three different treatment islands in Guntersville Reservoir, Alabama. Samples were collected from randomly selected plot points from islands that were placed into three different treatment types: Colony (currently occupied by Double-crested Cormorants) (Phalacrocorax auritus; n = 5), Historic (historically occupied by cormorants and currently abandoned; n = 3) and Reference (never occupied by cormorants; n = 4). We compared vegetation and tree metrics such as structure and diversity, as well as soil chemistry and bird diversity and communities among islands within Guntersville Reservoir. These data document for the first time that we are aware of the long-term effects of soil chemistry changes, vegetation changes, and impacts to avian diversity, in temperate forest ecosystems, by cormorant colonies. All data is associated with the recent article by Veum et al. [1] and provided here as raw data.
... The Holdridge Life Zones system is a global bioclimatic classification of land areas that correlates vegetation type with climatic data (Holdridge, 1947). Life Zones are classified according to precipitation, evapotranspiration potential, biotemperature (daily mean temperature above 0°C over a year) and elevation (Lugo, Brown, Dodson, Smith, & Shugart, 1999). While these individual variables are difficult to constrain, often impossible for the fossil record, Life Zones can be determined from flora and fauna taxa including microfossils, even in deep times (e.g. for Cretaceous/Paleogene transition; Bowman, Francis, Askin, Riding, & Swindles, 2014). ...
Article
Most source‐to‐sink studies typically focus on the dynamics of clastic sediments and consider erosion, transport and deposition of sediment particles as the sole contributors. Although often neglected, dissolved solids produced by weathering processes contribute significantly in the sedimentary dynamics of basins, supporting chemical and/or biological precipitation. Calcium ions are usually a major dissolved constituent of water drained through the watershed and may facilitate the precipitation of calcium carbonate when supersaturating conditions are reached. The high mobility of Ca2+ ions may cause outflow from an open system and consequently loss. In contrast, in closed basins all dissolved (i.e., non‐volatile) inputs converge at the lowest point of the basin. The endoreic Great Salt Lake basin constitutes an excellent natural laboratory to study the dynamics of calcium on a basin scale, from the erosion and transport through the watershed to the sink, including sedimentation in lake’s waterbody. The current investigation focused on the Holocene epoch. Despite successive lake level fluctuations (amplitude around 10 m), the average water level seems to have not been affected by any significant long‐term change (i.e. no increasing or decreasing trend, but fairly stable across the Holocene). Weathering of calcium‐rich minerals in the watershed mobilizes Ca2+ ions that are transported by surface streams and subsurface flow to the Great Salt Lake (GSL). Monitoring data of these flows was corrected for recent anthropogenic activity (river management) and combined with direct precipitation (i.e., rain and snow) and atmospheric dust income into the lake, allowing estimating the amount of calcium delivered to the GSL. These values were then extrapolated through the Holocene period, and compared to the estimated amount of calcium stored in GSL water column, porewater and sediments (using hydrochemical, mapping, coring and petrophysical estimates). The similar estimate of calcium delivered (4.88 Gt) and calcium stored (3.94 Gt) is consistent with the premise of the source‐to‐sink approach: a mass‐balance between eroded and transported compounds and the sinks. The amount of calcium deposited in the basin can therefore be predicted indirectly from the different inputs, which can be assessed with more confidence. When monitoring is unavailable (e.g., in the fossil record), the geodynamic context, the average lithology of the watershed and the bioclimatic classification of an endoreic basin are alternative properties that may be used to estimate the inputs. We show that this approach is sufficiently accurate to predict the amount of calcium captured in a basin and can be extended to the whole fossil record and inform on the storage of calcium.
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A biome is a major regional ecological community characterized by distinctive life forms and principal plants. Many empirical schemes such as the Holdridge life zone (HLZ) system have been proposed and implemented to predict the global distribution of terrestrial biomes. Knowledge of physiological climatic limits has been employed to predict biomes, resulting in more precise simulation; however, this requires different sets of physiological limits for different vegetation classification schemes. Here, we demonstrate an accurate and practical method to construct empirical models for biome mapping: a convolutional neural network (CNN) was trained by an observation-based biome map, as well as images depicting air temperature and precipitation. Unlike previous approaches, which require assumption(s) of environmental constrain for each biome, this method automatically extracts non-linear seasonal patterns of climatic variables that are relevant in biome classification. The trained model accurately simulated a global map of current terrestrial biome distribution. Then, the trained model was applied to climate scenarios toward the end of the 21st century, predicting a significant shift in global biome distribution with rapid warming trends. Our results demonstrate that the proposed CNN approach can provide an efficient and objective method to generate preliminary estimations of the impact of climate change on biome distribution. Moreover, we anticipate that our approach could provide a basis for more general implementations to build empirical models of other climate-driven categorical phenomena.
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Forecasting ecosystem response to climate change is critical for guiding policymaking but challenging due to: complicated relationships between microclimates and regional climates; species’ responses that are driven by extremes rather than averages; the multifaceted nature of species’ interactions; and the lack of historical analogs to future climates. Given these challenges, even model systems such as the Galapagos Islands, a world‐famous biodiversity hotspot and World Heritage Site, lack clear forecasts for future environmental change. Here, we developed a novel nonparametric method for simulating the ecosystem futures based on observed vegetation productivity (NDVI) during analogous weather observed historically. Using satellite images taken from the past to piece together a simulated future, we projected that productivity of terrestrial vegetation of the Galapagos will increase over the next century by approximately one standard deviation archipelago‐wide, with largest increases during the wet season (January to June) and in the arid zones. Such greening would impact a variety of ecological and evolutionary processes, species of conservation concern, and agricultural practices. Our straightforward approach can be applied to many other regions, particularly those with rapid ecosystem responses to stochastic inter‐annual climatic fluctuations that provide appropriate climate analogs for forecasting.
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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.
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Twenty-five years ago, we published a global seasonal snow classification now widely used in snow research, physical geography, and as a mission planning tool for remote sensing snow studies. Performing the classification requires global datasets of air temperature, precipitation, and land-cover. When introduced in 1995, the finest resolution global datasets of these variables were on a 0.5° × 0.5° latitude-longitude grid (approximately 50 km). Here we revisit the snow classification system and, using new datasets and methods, present a revised classification on a 10-arcsecond × 10-arcsecond latitude-longitude grid (approximately 300 m). We downscaled 0.1° × 0.1° latitude-longitude (approximately 10 km) gridded meteorological climatologies (1981-2019, European Centre for Medium-Range Weather Forecasts [ECMWF] ReAnalysis, 5 th Generation Land [ERA5-Land]) using MicroMet, a spatially distributed, high-resolution, micro-meteorological model. The resulting air temperature and precipitation datasets were combined with European Space Agency (ESA) Climate Change Initiative (CCI) GlobCover land-cover data (as a surrogate for wind speed) to produce the updated classification, which we have applied to all of Earth’s terrestrial areas. We describe this new, high-resolution snow classification dataset, highlight the improvements added to the classification system since its inception, and discuss the utility of the climatological snow classes at this much higher resolution. The snow class dataset (Global Seasonal-Snow Classification 2.0) and the tools used to develop the data are publicly available online at the National Snow and Ice Data Center (NSIDC).
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The concept of plant functional types (PFTs) is shown to be beneficial in representing the complexity of plant characteristics in land use and climate change studies using regional climate models (RCMs). By representing land use and land cover (LULC) as functional traits, responses and effects of specific plant communities can be directly coupled to the lowest atmospheric layers. To meet the requirements of RCMs for realistic LULC distribution, we developed a PFT dataset forEurope (LANDMATE PFT Version 1.0 Reinhart et al., 2021b, ;). The dataset is based on the high-resolution ESA-CCI land cover dataset and is further improved through the the additional use of climate information. Within the LANDMATE PFT dataset, satellite-based LULC information and climate data are combined to achieve the best possible representation of the diverse plant communities and their functions in the respective regional ecosystems while keeping the dataset most flexible for application in RCMs. Each LULC class of ESA-CCI is translated into PFT or PFT fractions including climate information by using the Holdridge Life Zone concept. Through the consideration of regional climate data, the resulting PFT map for Europe is regionally customized. A thorough evaluation of the LANDMATE PFT dataset is done using a comprehensive ground truth database over the European Continent. A suitable evaluation method has been developed and applied to assess the quality of thenew PFT dataset. The assessment shows that the dominant LULC groups, cropland and woodland, are well represented within the dataset while uncertainties are found for some less represented LULC groups. The LANDMATE PFT dataset provides a realistic, high-resolution LULC distribution for implementation in RCMs and is used as basis for the LUCAS LUC dataset introduced in the companion paper by Hoffmann et al. (submitted) which is available for use as LULC change input for RCM experiment setups focused on investigating LULC change impact.
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The spatial distribution of potential vegetation types in Qinghai-Tibet Plateau presents a significant vertical zonation. Explicating the vertical differences of potential vegetation distribution under future climate change in Qinghai-Tibet Plateau is an important issue for understanding the response of terrestrial ecosystem to climate change. Based on the observed climate data in 1981–2010 (T0), the scenario data of RCP 2.6, RCP 4.5 and RCP 8.5 released by CMIP5 in 2011–2040 (T1), 2041–2070 (T2) and 2071–2100 (T3), and the digital elevation model (DEM) data, the Holdridge life zone (HLZ) model has been improved to simulate the scenarios of potential vegetation distribution in the different gradient zones of Qinghai-Tibet plateau. The shift model of mean center has been improved to calculate the shift direction and distance of mean center in the potential vegetation types. The ecological diversity index was introduced to compute the ecological diversity change of potential vegetation. The simulated results show that there are 17 potential vegetation types in Qinghai-Tibet Plateau. Wet tundra, high-cold moist forest and nival are the major potential vegetation types and cover 56.26% of the total area of Qinghai-Tibet Plateau. Under the three scenarios, the nival would have the largest decreased area that would be decreased by 3.340 × 10⁴ km² per decade, and the high-cold wet forest would have the greatest increased area that would be increased by 3.340 × 10⁴ km² on average per decade from T0 to T3. The potential vegetation types distributed in the alpine zone would show the fastest change ratio (11.32% per decade) and that in low mountain and other zone would show the slowest change ratio (7.54% per decade) on average. The ecological diversity and patch connectivity of potential vegetation would be decreased by 0.108% and 0.290% per decade on average from T0 to T3. In general, the potential vegetation types distributed in the high elevation area generally have a higher sensitivity to climate change in Qinghai-Tibet plateau in the future.
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Climate change is projected to have a major influence on forest tree populations and composition. Translocation of species outside their historic range has been suggested to maintain healthy forests and tree species. The introduction of exotic species into botanical gardens and arboretums worldwide demonstrates the ability of many trees to grow outside their natural habitat and may play an important part in avoiding climate driven extinction if grown in a matching climate. However, it remains to be determined which climatic factors are the most important predictors of climatic match. In this study we use information from the arboretum in Hørsholm, Denmark, to analyse differences in performance of translocated Oak (Quercus) and show how data from tree collections can be used to predict success of assisted migration. Our data included archive lists of georeferenced Northern hemisphere introductions of Quercus, and assessments of their survival and growth rates in nursery and the Hørsholm arboretum. Using logistic and linear regression we modelled the importance of different bioclimatic predictor variables for survival and growth rate. Several correlations were identified across the Quercus genus. Survival of Quercus species depended primarily on the temperatures at the origin, whereas growth on the other hand was more dependent on a match in precipitation. The negative correlations indicated that introductions were less successful from sites with higher temperatures and wetter conditions. The study demonstrates an approach to use historical data collected from arboreta and botanical gardens in climate change research. This new approach can provide useful information in relation to assisted migration for an array of poorly investigated species where this may be the only source of information.
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Öz: İçinde bulunan çevrenin özellikleri iklim-vejetasyon sınıflandırma yöntemleri sayesinde daha kolay bir şekilde tasvir edilebilir. Bu çalışmanın amacı Türkiye'deki yaşam-alanlarını belirlemek ve bu alanların arazideki gerçek bitki-örtüsü ile karşılaştırmaktır. Bu amaçla bir tür iklim ve vejetasyon sınıflandırma yöntemi olan Holdridge yöntemi uygulandı. Çalışmada, Meteoroloji Genel Müdürlüğü tarafından sağlanan 1970 ile 2016 yılları arasındaki aylık ortalama sıcaklık ve yağış verileri kullanıldı. Eksik veriler ise Kriking yönteminin Fortran95 temelli bir yazılımı geliştirilerek tamamlandı. Ancak, ilgili meteoroloji istasyondaki eksik verilerin oranı %7'sinden fazla ise değerlendirme dışı tutuldu. Ek olarak, verilere homojenlik testi uygulandı ve %95 güven seviyesinde testi başaran veri dikkate alındı. Yöntemde kullanılan veriler ise yağış, bio-sıcaklık ve potansiyel buharlaşma oranıdır. Elde edilen yaşam-alan verilerin haritaları, ArcGIS 10.2 Coğrafi Bilgi Sistemleri (CBS) içindeki Thiessen poligonlar methodu uygulanarak üretildi. Elde edilen ana sonuçlara göre, Türkiye'de 12 farklı yaşam zonu mevcuttur. Bu yaşam-alanları sıklık sırasına göre, "Serin ılıman step", "Sıcak ılıman kuru orman" ve "Serin ılıman nemli orman" şeklinde sıralanır. Bu yaşam-alanların toplam içindeki oranı %77 civarındadır. Çalışmanın bir başka sonucu ise, yükselti ve eğimin fazla olduğu alanlarda ve yoğun bitki örtüsü türünün gözlemlendiği nemli kıyı bölgelerinde birden fazla yaşam-zonuna ait özelliklerin görülmesidir. Diğer taraftan, Türkiye'deki iklim ve bitki-örtüsü etkileşim ilişkileri dikkate alındığında, Holdridge yöntemi ile bulunan yaşam-alanlarından bazıları gözlenen bitki-örtüsü özelliklerini yansıtmamaktadır. Bu durum, ancak yanlış arazi-kullanımı politikaları ve kuvvetlenen iklim değişikliği ile açıklanabilir. Dolayısıyla, çalışmanın ileride arazi-kullanım planlarında karar vericilere destekler sunacağını öneriyoruz. Abstract: The surrounding features can be more easily depicted by means of climate-vegetation classification methods. The aim of this study is to determine the life-zones in Turkey and to compare them with the actual vegetation-cover in the related areas. For this purpose, a kind of climate and vegetation classification method called Holdridge Life-Zone (HLZ) method was applied. In the application, monthly average temperature and precipitation values from 1970 to 2016 provided by the General Directorate of Turkish Meteorology Service were used. In the case of complete the missing data kriging method, a Fortran95 based source code was developed. However, if the proportion of missing data in the related meteorological station is more than 7%, it is removed. In addition, the homogeneity test was performed on the data, and the set that achieved the test at the 95% confidence level were considered. The data used in the method are precipitation, bio-temperature and potential evaporation ratio. The maps of the acquired HLZ were generated by applying the Thiessen polygons method in the ArcGIS 10.2 Geographic Information Systems (GIS). According to the main results, 12 different life zones are obtained in Turkey. These are: "Cool temperate steppe", "Warm temperate dry forest" and "Cool temperate moist forest" according to their frequency. The proportion of these life zones within the total is about 77%. Another consequence of the work is that there are more than one life-zone features in the areas with * İletişim yazarı: Mehmet Kadri Tekin,
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The Holdridge life zone (HLZ) method is applied to map potential vegetation types in Turkey. The HLZ map is compared to a map of actual vegetation in order to assess the degradation status of vegetation in Turkey. Data required to identify HLZ classes are provided by the General Directorate of Meteorology, while the current vegetation status is estimated with data provided by the General Directorate of Forestry. After weather data are cleaned and missing values are replaced, the HLZ type is estimated for each station, and then thematic maps are created using the ArcGIS software. The study reveals that there are 12 HLZ types in Turkey. The three dominant types are as follows: cool temperate steppe, warm temperate dry forest, and cool temperate moist forest. In regions where physical geographical controls change in short distances, the biodiversity is greater, and linked to this, the HLZ diversity also appears to be greater. Comparing the identified life zones to the actual vegetation, in some areas, remarkable mismatches can be found. Although, in some regions, the life zone type is consistent with the land cover type, in some narrow areas, the potential vegetation does not reflect features of the current vegetation cover. Considering limitations and capabilities of the assessment approach used in this study, we think that the incompatibility between actual and modelled vegetation types in the eastern region of Turkey is caused by the intensive landscape use. The goal of this research is to support future bioclimatic studies and land use management strategies.
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