Areas Of High Species Richness Research Articles

Species richness of the globally distributed, arctic–alpine genus Draba L. (Brassicaceae)

Draba includes over 390 species distributed globally, mostly in extreme ecosystems at high elevations and latitudes making it the most successful and species-rich genus of the Brassicaceae, particularly in mountain and alpine regions. In this analysis, species richness data were collected from floras and checklists, and species distribution patterns were compared on a global scale for 367 of the species. A compilation of the geographical distribution of the entire genus using a presence/absence matrix was generated and displayed upon geographical maps. The three areas of highest species richness are the northern Andes (48 spp.), central Rocky Mountains (49 spp.), and Tibetan Plateau/C-SW Chinese (Hengduan) mountains (52 spp.). Previous phylogenetic analyses are in congruence with the area cladogram shown herein. It is shown that Draba has a diverse range of distribution patterns from widely spread to narrowly endemic. Species with wider distributions are frequently found in the Arctic, while those with a more narrow distribution are restricted to high elevations. However, ploidy-level information as well as recently presented genetic data convincingly indicates that the European and West Asian biota have served as a primary source and center of origin of the large diversity in the genus. A complete list of accepted Draba species is provided.

Mind the (information) gap: the importance of exploration and discovery for assessing conservation priorities for freshwater fish

AbstractBiodiversity conservation often is aimed at areas of high species richness and endemism. Our understanding of freshwater fish diversity in the Neotropics is biased by lack of exploration within mountainous regions that historically have been difficult to access. These regions are particularly likely to contain high species endemism. The upper Mazaruni River drainage is hydrogeographically and climatically distinct from the rest of the Essequibo Basin. Recent ichthyological expeditions to the upper Mazaruni discovered up to 32 species previously unknown to science and a fish assemblage with perhaps the highest level of endemism in the Neotropics. This unique ichthyofauna is threatened by gold mining that has severely degraded aquatic habitats and therefore requires immediate protection.

Effects of urban structure on plant species richness in a large European city

Urban areas have developed under anthropogenic impact and hence feature strongly altered environmental conditions that influence today’s plant species distribution. Generally, urban areas are rich in plant species, but on smaller scales richness can vary considerably. Our study aim is to identify areas of high species richness and to assess richness distribution patterns in the city of Hamburg by analyzing a floristic mapping dataset on the scale of 1 km2. Differences in plant species richness were analyzed between three urbanization zones. With multiple regression analyses, we tested effects of urban structure, habitat, and environmental conditions on the distribution of species richness measures. Total species richness per 1 km2 was 274 ± 60 on average and differed only slightly between the urbanization zones. It increased with habitat diversity and decreased with Ellenberg indicator values (EIV) for nutrients (multiple R2 = 0.31). Proportion of non-native species increased with mean annual temperature and decreased with EIVs for moisture (multiple R2 = 0.72), while proportion of endangered species increased with EIVs for moisture and decreased with EIVs for nutrients (multiple R2 = 0.66). Proportion of thermophilic species (multiple R2 = 0.58) could be explained by mean annual temperature. The emerging patterns probably differ from those in other cities due to the central port harboring a particular flora. Besides the expected high proportions of non-native species, high proportions of endangered species were also found in this area. Our results contribute to identifying drivers of biodiversity in cities and can thus be used to develop measures for the conservation of urban biodiversity.

Amphibian Conservation in the Caatinga Biome and Semiarid Region of Brazil

Abstract The Brazilian Ministry of the Environment (Ministerio Do Meio Ambiente, MMA) proposed defining priority areas for Brazilian biodiversity conservation in 2007, but to date, no definitions of priority areas for amphibian conservation have been developed for the Caatinga biome or the semiarid region of Brazil. In this study, we searched for “hot spots” of amphibians in these two regions and assessed whether the priority areas established by the MMA coincided with those suitable for amphibian conservation. We determined amphibian hot spots by means of three estimates: areas of endemism, areas of high species richness, and areas with species that are threatened, rare, or have very limited distributions. We then assessed the degree of coincidence between amphibian hot spots and the priority areas of the MMA based on the current conservation units. We analyzed areas of endemism with the use of a parsimony analysis of endemicity (PAE) on quadrats. The Caatinga biome and semiarid region showed four and si...

Implications of bias in conservation research and investment for freshwater species

Human population growth and economic development threaten the integrity of freshwater ecosystems globally, reducing their ability to support biodiversity and provide ecosystem services. However, our knowledge of freshwater biodiversity is fragmented due to bias in conservation research toward primarily terrestrial or charismatic taxonomic groups. Here, we utilize the most comprehensive assessment of freshwater biodiversity for an entire continent to examine the implications of this shortfall. Results indicate that groups that have been the focus of most conservation research are poor surrogates for patterns of both richness and threat for many freshwater groups, and that the existing protected area network underrepresents freshwater species. Areas of highest species richness and threat are congruent with areas where reliance on ecosystem services by humans and pressures placed on freshwater ecosystems are high. These results have implications for targets to reduce biodiversity loss and safeguard associated ecosystem services on which millions of people depend globally.

Hotspots of species richness, threat and endemism for terrestrial vertebrates in SW Europe

The Mediterranean basin, and the Iberian Peninsula in particular, represent an outstanding “hotspot” of biological diversity with a long history of integration between natural ecosystems and human activities. Using deductive distribution models, and considering both Spain and Portugal, we downscaled traditional range maps for terrestrial vertebrates (amphibians, breeding birds, mammals and reptiles) to the finest possible resolution with the data at hand, and we identified hotspots based on three criteria: i) species richness; ii) vulnerability, and iii) endemism. We also provided a first evaluation of the conservation status of biodiversity hotspots based on these three criteria considering both existing and proposed protected areas (i.e., Natura 2000). For the identification of hotspots, we used a method based on the cumulative distribution functions of species richness values. We found no clear surrogacy among the different types of hotspots in the Iberian Peninsula. The most important hotspots (considering all criteria) are located in the western and southwestern portions of the study area, in the Mediterranean biogeographical region. Existing protected areas are not specifically concentrated in areas of high species richness, with only 5.2% of the hotspots of total richness being currently protected. The Natura 2000 network can potentially constitute an important baseline for protecting vertebrate diversity in the Iberian Peninsula although further improvements are needed. We suggest taking a step forward in conservation planning in the Mediterranean basin, explicitly considering the history of the region as well as its present environmental context. This would allow moving from traditional reserve networks (conservation focused on “patterns”) to considerations about the “processes” that generated present biodiversity.

Lizard species richness patterns in China and its environmental associations

Many ecological hypotheses have been widely used to explain species richness variation across the globe. We investigated lizard species richness patterns in China, and identified areas of high species richness. Furthermore, we tested hypotheses concerning the relationships between lizard richness and environmental variables. A large data including 30,902 records of point locality data for 151 lizard species occurring in China were retrieved from Herpetology museums of CIB/CAS and other museums through HerpNET, and published sources, and then predicted distributions maps were generated using ecological niche modeling. We overlaid all species prediction maps into a composite map to describe species richness patterns. A multiple regression analysis using eigenvector-based spatial filtering (SEVM) was performed to examine the best environmental predictors of species richness. Richness peaked mainly in southern China located in the Oriental realm. Our best multiple regression models explained a total of 80.1% variance of lizard richness (r2 = 0.801; F = 203.47; P < 0.001). Among related factors in shaping species richness distribution, the best environmental predictors of species richness were: frost-day frequency, elevation, vegetation, and wet-day frequency. Based on models selection, our results revealed that underlying mechanisms related to different ecological hypotheses might work together and best explain lizard richness in China. We are in an initial step to develop a large data set on species richness, and provide the necessary conservation implications from habitat loss. Additional studies that test species richness at different geographical scale are required to better understand the factors that may influence the species richness distribution in East Asia.

Area prioritization and performance evaluation of the conservation area network for the Moroccan herpetofauna: a preliminary assessment

The integration of spatial area prioritization algorithms and species distribution modelling has shown great promise in conservation planning in recent years. However, despite the fact that reptiles and amphibians have the highest threat status of all terrestrial vertebrates, these species are often under-represented in conservation planning. The Kingdom of Morocco possesses the richest and most varied herpetofauna in the Maghreb and the western Mediterranean, and is characterized by high species richness, endemism and number of European relict species. Despite the fact that Moroccan reptiles and amphibians have been the subject of numerous studies by a large number of international herpetologists since the beginning of the 20th century, few or none of these concerned their conservation. This study had three main objectives: (1) to identify those areas that harbour the highest species richness; (2) to evaluate the existing and proposed future ‘important biological and ecological sites’ (SIBES) conservation area network (CAN) with respect to their ability to protect the herpetofauna adequately; and (3) to identify priority areas into which the existing protected areas can be augmented. We used maximum-entropy species distribution modelling to run distribution models for 11 amphibian and 86 reptile species (27.6% endemics and 12.4% threatened) for which we had 2,170 single geographic records. A total of 97 models were used to create a richness map of the Moroccan herpetofauna and thereby detect both areas of high species richness and the distribution patterns of individual species. This map was subsequently used as a basis for performance evaluation of the CAN and area prioritization using the ConsNet conservation planning software initialized by “Rarity” first, while using representation targets of 5% and 10%. Additionally, the proposed future Moroccan CAN (SIBES) was evaluated in terms of its overlay and proximity with ConsNet solutions using visual interpretation and distance measurements in a GIS. Our results show that Moroccan herpetofauna is poorly protected under the existing and future CAN. Prioritization of areas shows that a major increase in conservation area is required to guarantee the persistence of individual herpetofauna species even with a global minimum representation target of only 10%. An increase of the existing CAN is especially needed along parts of the Atlantic coast, in the north-western Mediterranean region, on the north-eastern Moroccan coast, as well as in several areas in the Sahara, notably vast proportions of the Vallee du Haut and Bas Drâa.

Global patterns and predictors of marine biodiversity across taxa

Global patterns of species richness and their structuring forces have fascinated biologists since Darwin and provide critical context for contemporary studies in ecology, evolution and conservation. Anthropogenic impacts and the need for systematic conservation planning have further motivated the analysis of diversity patterns and processes at regional to global scales. Whereas land diversity patterns and their predictors are known for numerous taxa, our understanding of global marine diversity has been more limited, with recent findings revealing some striking contrasts to widely held terrestrial paradigms. Here we examine global patterns and predictors of species richness across 13 major species groups ranging from zooplankton to marine mammals. Two major patterns emerged: coastal species showed maximum diversity in the Western Pacific, whereas oceanic groups consistently peaked across broad mid-latitudinal bands in all oceans. Spatial regression analyses revealed sea surface temperature as the only environmental predictor highly related to diversity across all 13 taxa. Habitat availability and historical factors were also important for coastal species, whereas other predictors had less significance. Areas of high species richness were disproportionately concentrated in regions with medium or higher human impacts. Our findings indicate a fundamental role of temperature or kinetic energy in structuring cross-taxon marine biodiversity, and indicate that changes in ocean temperature, in conjunction with other human impacts, may ultimately rearrange the global distribution of life in the ocean.

Evaluating the sampling bias in pattern of subterranean species richness: combining approaches

We investigated the pattern of species richness of obligate subterranean (troglobiotic) beetles in caves in the northwestern Balkans, given unequal and biased sampling. On the regional scale, we modeled the relationship between species numbers and sampling intensity using an asymptotic Clench (Michaelis-Menten) function. On the local scale, we calculated Chao 2 species richness estimates for 20 9 20 km grid cells, and investigated the distribution of uniques, species found in only one cave within the grid cell. Cells having high positive residuals, those with above average species richness than expected according to the Clench function, can be considered true hotspots. They were nearly identical to the observed areas of highest species richness. As sampling intensity in a grid cell increases the expected number of uniques decreases for any fixed number of species in the grid cell. High positive residuals show above average species richness for a certain level of sampling intensity within a cell, so further sampling has the most potential for additional species. In some cells this was supported by high numbers of uniques, also indicating insufficient sampling. Cells with low negative residuals have fewer species than

Rarest of the rare: advances in combining evolutionary distinctiveness and scarcity to inform conservation at biogeographical scales

AbstractAim In an era of global habitat loss and species extinction, conservation biology is increasingly becoming a science of triage. A key approach has been the designation of global biodiversity hotspots – areas of high species richness and endemism – prioritizing regions that are disproportionately valuable. However, traditional hotspot approaches leave absent information on species evolutionary histories. We argue that prioritizing the preservation of evolutionary diversity is one way to maximize genotypic and functional diversity, providing ecosystems with the greatest number of options for dealing with an uncertain future.Location Global.Methods We review methods for encapsulating phylogenetic diversity and distinctiveness and provide an illustration of how phylogenetic metrics can be extended to include data on geographical rarity and inform conservation prioritization at biogeographic scales.Results Abundance‐weighted metrics of evolutionary diversity can be used to simultaneously prioritize populations, species, habitats and biogeographical regions.Main conclusion Policy makers need to know where scarce conservation funds should be focused to maximize gains and minimize the loss of biological diversity. By incorporating these evolutionary diversity metrics into prioritization schemes, managers can better quantify the valuation of different regions based on evolutionary information.

Analysis of Museum Records Highlights Unprotected Land Snail Diversity in Alabama*

In order to address the conservation status and needs of Alabama's land snail species, we examined their diversity and distribution using 11,816 museum records representing 226 land snail species. The Chao-1 statistic identified seven areas of high species richness. The areas with the highest richness contain an estimated 200 species of land snail. These seven areas are not currently well protected by state or federal lands. While taxonomic misidentification and geo-referencing quality may be inflating our results, we suggest that studies like ours provide valuable baseline diversity estimates and launching points for continued studies.

Climate‐based models of spatial patterns of species richness in Egypt’s butterfly and mammal fauna

AbstractAim Identifying areas of high species richness is an important goal of conservation biogeography. In this study we compared alternative methods for generating climate‐based estimates of spatial patterns of butterfly and mammal species richness.Location Egypt.Methods Data on the occurrence of butterflies and mammals in Egypt were taken from an electronic database compiled from museum records and the literature. Using Maxent, species distribution models were built with these data and with variables describing climate and habitat. Species richness predictions were made by summing distribution models for individual species and by modelling observed species richness directly using the same environmental variables.Results Estimates of species richness from both methods correlated positively with each other and with observed species richness. Protected areas had higher species richness (both predicted and actual) than unprotected areas.Main conclusions Our results suggest that climate‐based models of species richness could provide a rapid method for selecting potential areas for protection and thus have important implications for biodiversity conservation.

Species richness and polyploid patterns in the genus Draba (Brassicaceae): a first global perspective

Background : The genus Draba (Brassicaceae) has an arctic-alpine and montane distribution, and contains 355 accepted species that encompass a broad range of ploidy levels. Aims : We aimed (1) to explore the relationship between ploidy level and species richness throughout the geographical distribution of Draba, and (2) to estimate rates of speciation and polyploidisation in the genus. Methods : Species and their ploidy levels, obtained from Floras, herbaria and checklists, were mapped and analysed with ArcView 9.1. Speciation and polyploidisation rates were calculated. Results : We found that: (1) areas of high species richness have a high number of polyploid species; (2) diploid and polyploid distributions overlap; (3) aneuploids, and uneven and lower polyploid levels (≤ 6x) are strongly associated with the North American Cordillera; (4) species with high ploidy levels (> 10x) occur mainly in the Circum-North Region; and (5) Draba has high rates of speciation and polyploidisation compared to other herbaceous plants. Conclusions : Draba is a young polyploid complex as indicated from the geographical overlap of diploids and polyploids. The North American Cordillera Region is characterised by recent speciation and radiation events, while the Circum-North Region is characterised by both high levels of species migration and high ploidy levels. Regions of high species richness and polyploidy are those most affected by past glaciation (i.e. mountainous and arctic regions). High rates of speciation and polyploidy support the hypothesis that speciation in the genus has accelerated, and it is hypothesised that frequent glaciation cycles during the Pleistocene were a cause of this acceleration.

The value of georeferenced collection records for predicting patterns of mosquito species richness and endemism in the Neotropics

Abstract 1. Determining large‐scale distribution patterns for mosquitoes could advance knowledge of global mosquito biogeography and inform decisions about where mosquito inventory needs are greatest.2. Over 43 000 georeferenced records are presented of identified and vouchered mosquitoes from collections undertaken between 1899 and 1982, from 1853 locations in 42 countries throughout the Neotropics. Of 492 species in the data set, 23% were only recorded from one location, and Anopheles albimanus Wiedemann is the most common species.3. A linear log–log species–area relationship was found for mosquito species number and country area. Chile had the lowest relative density of species and Trinidad‐Tobago the highest, followed by Panama and French Guiana.4. The potential distribution of species was predicted using an Ecological Niche Modelling (ENM) approach. Anopheles species had the largest predicted species ranges, whereas species of Deinocerites and Wyeomyia had the smallest.5. Species richness was estimated for 1° grids and by summing predicted presence of species from ENM. These methods both showed areas of high species richness in French Guiana, Panama, Trinidad‐Tobago, and Colombia. Potential hotspots in endemicity included unsampled areas in Panama, French Guiana, Colombia, Belize, Venezuela, and Brazil.6. Argentina, The Bahamas, Bermuda, Bolivia, Cuba, and Peru were the most under‐represented countries in the database compared with known country species occurrence data. Analysis of species accumulation curves suggested patchiness in the distribution of data points, which may affect estimates of species richness.7. The data set is a first step towards the development of a global‐scale repository of georeferenced mosquito collection records.

Erratum: Species richness and biodiversity conservation priorities in British Columbia, Canada

Patterns in the geographic distribution of seven species groups were used to identify important areas for conservation in British Columbia, Canada. Potential priority sites for conservation were determined using an integer programming algorithm that maximized the number of species represented in the minimum number of sites. Sweep analyses were used to determine how well the set of priority sites identified for each species group represented the other species groups. Although areas of highest species richness were different for each species group, they all included sites in the southern interior of British Columbia, where there is limited protection. Furthermore, less than 13% of the distribution ranges for 23 of 25 bird species of special conservation concern were located within existing protected areas. Species at risk of extinction were poorly represented (26%–42%) in priority sets of sites selected for amphibians, reptiles, birds, and mammals, since these sites were generally scattered throughout the p...

Evolutionary biology and practical conservation: bridging a widening gap

At the ecosystem, species and population level, available measures suggest that average rates of loss of populations and habitats are now around 1% per year and seem likely to increase in the future. Habitat conversion continues in most parts of the world, especially in areas of high species richness, and novel threats, especially climate change, will pose new challenges. With this pressure, maintaining evolutionary processes in natural populations will be critical to longer term persistence, and will often require specific planning relevant to the context. However, in many areas of policy and practice, urgent actions tend to focus on pattern-based analyses and considerations of evolutionary and ecological processes are neglected. At a variety of levels, from setting goals to implementing conservation management at the site or species level, there are simple adjustments that can be made. Improved methods for integrating the work of scientists and policymakers is recommended, from the beginning to end of the planning process.

Biodiversity, conservation, and hotspot atlas of Costa Rica: a dung beetle perspective (Coleoptera: Scarabaeidae: Scarabaeinae)

This paper is an analysis of the distribution of areas of high species richness and endemicity based on dung beetles living in the different Holdridge life-zones of Costa Rica by using a geographic information system (GIS). Endemism was examined in relation to whether the species were shared with Nicaragua and/or Panama, or if they were strictly Costa Rican. The species composition of dung beetle distributions in the sampling areas and life-zones was evaluated. Species distribution was also analyzed in relation to altitudinal levels. The species richness and endemicity maps served as a base for doing a gap analysis and defining four different levels of high priority conservation areas. We also investigated what percentage of these priority areas is under some type of protection or conservation scheme and which of these areas should be enlarged. Also considered is the feasibility that these areas under protection have for enlargement, considering possible problems and interactions with present land-use. We include a list of all the recorded dung beetle species for Costa Rica, as well as their presence in the different Holdridge life-zones and their endemicity status. This study clearly demonstrates the need to include insects in biodiversity-endemicity studies because different and more detailed results are obtained in relation to vertebrate and plant-based studies.

Environmental Correlates for Species Richness among Amphibians and Reptiles in a Climate Transition Area

Correlations between environmental factors and the distribution of amphibian and reptile species richness were investigated in a climate transition area, Peneda-Geres National Park (PNPG), in North-Western Portugal. Using presence-data at a local-scale (1 × 1 km), Ecological-Niche Factor Analysis (ENFA) identified a mixture of climatic (precipitation and number of days with fog), topographical (altitude and relief) and habitat factors (number of watercourses and water surfaces, the type of the largest water surface and tree diversity cover), as accurate predictors of species occurrence. Three factors were common for both taxonomic groups, and consistently presented a positive relation with species occurrence: precipitation, number of water surfaces, and tree diversity cover; suggesting a strong coincidence in the environmental correlates that influence amphibian and reptile species richness. Distribution patterns of observed and predicted species richness were compared using a Geographical Information System. Overall, three high species richness areas were predicted in common for both taxonomic groups and two additional areas for amphibians only. These areas matched with the observed species richness but suggested larger areas of high species richness. The location of the PNPG in a biogeographic crossroad, between Euro-Siberian and Mediterranean provinces, emphasised species richness of amphibians and reptiles and suggests a high priority conservation status for this protected area. Most of Central-Northern Portugal is located in a climatic transition area; therefore, increased species richness should be expected for other areas. Local scale studies for other protected areas should be planned as a framework for the development of multi-scale conservation planning by Portuguese authorities.

Using Self-Organizing Maps to Explore Patterns in Species Richness and Protection

The combination of species distributions with abiotic and landscape variables using Geographic Information Systems can prioritize areas for biodiversity protection by identifying areas of high richness, although the number of variables and complexity of the relationships between them can prove difficult for traditional statistical methods. The use of these methods, which commonly assume linearity and low correlation between independent variables, can obscure even strong relationships and patterns. Self-Organizing Maps (SOM) is a heuristic statistical tool based on machine learning methods that can be used to explore patterns in large, complex datasets for linear and nonlinear patterns. Here we use SOM to visualize broad patterns in species richness by taxonomic group (birds, mammals, reptiles, and amphibians) and 78 habitat, landscape and environmental variables using data from the Gap analysis project for West Virginia, USA. Soil and habitat variables demonstrated clear relationships with species richness; areas with high species richness occurred in areas with high soil richness. Landscape metrics were less important, although habitat diversity and evenness indices were positively related to species richness in some taxonomic groups. Current coverage of protected areas (e.g., National Forests and state parks) appeared to be insufficient to cover most of the areas of high species richness, especially for reptiles; many of the polygons with the highest richness were not covered by these areas. The identification of polygons with high richness and low protection can be used to focus conservation efforts in those areas.