Suitable Habitat Research Articles

Plants, fungi, and carabid beetles in temperate forests: both observed and dark diversity depend on habitat availability in space and time

ContextThe loss of ancient forests threatens many species. Effective nature conservation needs information on how forest availability in the surrounding landscape in space and time determines the diversity of multiple taxa.ObjectivesWe explored the relationship between forest availability at different spatiotemporal scales and the diversity of various groups: vascular plants (woody species, ground layer), epiphytes (bryophytes and lichens), fungi (ectomycorrhizal, arbuscular mycorrhizal, pathogenic, saprotrophic), and carabid beetles. Besides the observed diversity, we also estimated dark diversity, i.e. suitable but absent species. Dark diversity is theoretically a sensitive metric in detecting ecosystem conditions as it is typically relatively large and contains susceptible species.MethodsWe recorded the observed diversity by field sampling and soil DNA in 100 temperate ancient old-growth forest sites in southern Estonia; dark diversity was estimated for the same sites using species co-occurrence data. Forest availability estimates were obtained from four topographic maps (1900s-2010s) at the 0.5–5 km radius.ResultsThe biodiversity of forest specialists was higher at larger historical forest availability at the spatial scale of 2–5 km radius. The diversity of light-demanding forest ecotone taxa mainly had negative relationships with young forests on previous agricultural lands (at 0.5–2 km radius). Dark diversity models were often more strongly associated with forest availability than observed diversity models.ConclusionsDark diversity enhances our understanding of how current and historical forest availability affects local biodiversity. As young forests cannot provide suitable habitats for many forest-dwelling species, stable forest habitats must be preserved as source areas to enhance biodiversity.

Spatial distribution of cliff plant species in the Balearic Islands under current and projected climatic scenarios

Cliff ecology has been studied for decades, providing information about its high biodiversity values and their vulnerability to climate change. Also, insular ecosystems present biodiversity hotspots with high endemicity, but they are also severely affected by anthropogenic effects. Together, insular cliff communities combine both biodiversity uniqueness and high vulnerability to global change, but few studies have evaluated these particular ecosystems. Our aim was to provide information on the spatial distribution of insular cliff-specific vegetation assessing which environmental and climatic variables contribute to the definition of cliff habitat conditions. Ecological niche modelling for cliff populations in Balearic Islands has been calculated with presences of 20 plant species and climatic and geographical variables using a Random Forest model. The most important climatic variables for the model generation were mean temperature of the driest quarter and precipitation of the coldest quarter. The map obtained showed that mountain ranges from all islands provide highly suitable conditions for rupicolous species. Both the pessimistic and optimistic models showed that the habitat suitability of cliff vegetation in the mountain ranges would decrease, while they are close to zero in lowlands for the period 2021–2040. This study emphasizes the vulnerability of cliff habitats to climate change due to their limited dispersal capacity and distribution and the strict requirements for habitat suitability. From this work, future studies can focus on single-species analysis to evaluate if any cliff specialist species can be at risk of extinction due to climate change.

Land conversion and lack of protection significantly reduce suitable wolf habitat amount and functional connectivity in the Adirondack-to-Laurentians (A2L) transboundary wildlife linkage

Land conversion and lack of protection significantly reduce suitable wolf habitat amount and functional connectivity in the Adirondack-to-Laurentians (A2L) transboundary wildlife linkage

Revisiting current distribution and future habitat suitability models for the endemic Malabar Tree Toad (Pedostibes tuberculosus) using citizen science data

Climate change is one of the major drivers of biodiversity loss. Among vertebrates, amphibians are one of the more sensitive groups to climate change due to their unique ecology, habitat requirements, narrow thermal tolerance and relatively limited dispersal abilities. We projected the influence of climate change on an endemic toad, Malabar Tree Toad (Pedostibes tuberculosus; hereafter MTT) from the Western Ghats biodiversity hotspot, India, for two different shared socio-economic pathways (SSP) using multiple modeling approaches for current and future (2061–2080) scenarios. The data used predominantly comes from a citizen science program, ‘Mapping Malabar Tree Toad’ which is a part of the Frog Watch citizen science program, India Biodiversity Portal. We also evaluated the availability of suitable habitats for the MTT in Protected Areas (PAs) under the current and future scenarios. Our results show that annual precipitation was the most important bioclimatic variable influencing the distribution of MTT. We used MaxEnt (MEM) and Ensemble (ESM) modeling algorithms. The predicted distribution of MTT with selected environmental layers using MEM was 4556.95 km2 while using ESM was 18,563.76 km2. Overlaying PA boundaries on predicted distribution showed 37 PAs with 32.7% (1491.37 km2) and 44 PAs with 21.9% (4066.25 km2) coverage for MEM and ESM respectively. Among eight future climate scenarios, scenarios with high emissions showed a decreased distribution range from 33.5 to 68.7% of predicted distribution in PAs, while scenarios with low emissions showed an increased distribution range from 1.9 to 111.3% in PAs. PAs from the Central Western Ghats lose most suitable areas with a shift of suitable habitats towards the Southern Western Ghats. This suggests that MTT distribution may be restricted in the future and existing PAs may not be sufficient to conserve their habitats. Restricted and discontinuous distribution along with climate change can limit the dispersal and persistence of MTT populations, thus enhanced surveys of MTT habitats within and outside the PAs of the Western Ghats are an important step in safeguarding the persistence of MTT populations. Overall, our results demonstrate the use of citizen science data and its potential in modeling and understanding the geographic distribution and the calling phenology of an elusive, arboreal, and endemic amphibian species.

Impact of carbon neutralization policy on the suitable habitat distribution of the North China leopard

The Chinese government has introduced a carbon neutral policy to cope with the rapid changes in the global climate. It is not clear what impact this policy will have on wildlife. Therefore, this study analyzed the suitable habitat distribution of China’s unique leopard subspecies in northern Shaanxi, and simulated the potential suitable habitat distribution under different carbon emission scenarios at two time points of future carbon peak and carbon neutralization. We found that in the future SSPs 126 scenario, the suitable habitat area and the number of suitable habitat patches of North China leopard will continue to increase. With the increase of carbon emissions, it is expected that the suitable habitat of North China leopard will continue to be fragmented and shifted. When the annual average temperature is lower than 8 °C, the precipitation seasonality is 80–90 mm and the precipitation of the warmest quarter is greater than 260 mm, the probability of occurrence of North China leopard is higher. The increase in carbon emissions will lead to the reduction, migration, and fragmentation of the suitable habitat distribution of the North China leopard. Carbon neutrality policies can protect suitable wild habitats. In the future, the impact of carbon neutrality policies on future wildlife habitat protection should be carried out in depth to effectively promote the construction of wildlife protection projects.

Nest-site selection of Eurasian Curlew (Numenius arquata) in the centre of its European range: adaptation to local macrohabitat factors

AbstractThe most important cause of the declining numbers of wading birds is a combination of habitat loss and degradation, as well as low productivity due to predation. Knowledge of the habitat requirements of this endangered group of species is critical for maintaining and restoring suitable breeding habitats. The aim of this paper is to characterize those habitat components of the Eurasian Curlew (Numenius arquata) which determine its choice of nesting site. This study was undertaken in three sites in Poland, the most important breeding areas of this species in this country. Our results showed that macrohabitat factors affect curlew nest-site selection in different ways. The most important ones were distance to a forest edge, the percentage cover of managed farmland in the vicinity and the number of farmland plots close to the nest. Other habitat components, such as distance to scattered trees, distance to roads and soil category, were of lesser importance and could be treated as localized. This study is a contribution to the knowledge of the Eurasian Curlew’s nest-site selection in farmland grasslands, which may have implications for its conservation.

Should I stay or move? Quantifying landscape of fear to enhance environmental management of road networks in a highly transformed landscape

The development and expansion of road networks pose considerable threats to natural habitats and wildlife, fostering a landscape of fear. In addition to direct mortality caused by road collisions, road construction and maintenance often result in habitat fragmentation and loss, impeding animal movement and gene flow between populations. Mountain ungulates are already confined to fragmented habitat patches and roads can cause substantial disturbances to their critical ecological processes, such as dispersal and migration. In this study, we employed two key mountain ungulates, the wild goat (Capra aegagrus) and mouflon (Ovis gmelini), as functional models to examine how road networks impact the quantity and connectivity of natural habitats in southwestern Iran, where extensive road construction has led to significant landscape changes. We used the MaxEnt method to predict species distribution, the circuit theory to evaluate habitat connectivity, and the Spatial Road Disturbance Index (SPROADI) to assess road impacts. During the modeling process, we selected eleven important variables and employed a model parametrization strategy to identify the optimal configuration for the MaxEnt model. For SPROADI index we used three sub-indices, including traffic intensity, vicinity impact, and fragmentation grade. We then integrated the results of these analyses to identify areas with the most significant environmental impacts of roads on the coherency of the natural habitats. The findings indicate that suitable habitats for wild goats are widely distributed across the study area, while suitable habitats for mouflon are primarily concentrated in the northeastern region. Conservation gap analysis revealed that only 8% of wild goat habitats and 7% of mouflon habitats are covered by protected areas (PAs). The SPROADI map highlighted that 23% of the study area is negatively influenced by road networks. Moreover, 30.4% of highest-probability corridors for mouflon, and 25.7% for wild goat, were highly vulnerable to the impacts of roads. Our combined approach enabled us to quantitatively assess species-specific vulnerability to the impacts of heavy road networks. This study emphasizes the urgent need to address the negative effects of road networks on wildlife habitats and connectivity corridors. Our approach effectively identifies sensitive areas, which can help inform mitigation strategies and support more effective conservation planning in significantly transformed landscapes.

Integrating Entropy Weight and MaxEnt Models for Ecotourism Suitability Assessment in Northeast China Tiger and Leopard National Park

The development of ecotourism in protected areas faces the challenge of balancing conservation and ecotourism. Ecotourism suitability assessments are essential tools for managing tourism in these areas. However, current assessments often overlook biological factors, leading to adverse effects on wildlife. This study uses the Northeast China Tiger and Leopard National Park as a case study to establish a comprehensive assessment system that integrates ecotourism suitability with tiger and leopard habitat suitability, thereby linking ecotourism with wildlife conservation. The primary research methods include ecotourism suitability analysis based on the entropy weight method and habitat suitability analysis using the MaxEnt model. Based on the zoning results of ecotourism and habitat suitability, a comprehensive ecotourism suitability zoning map was produced. This map indicates that areas of very high suitability account for 45.62% of the total area, covering approximately 6152.563 km2, and are primarily located on the edges of village clusters. These areas can be prioritized for developing tourism infrastructure. The comprehensive ecotourism assessment system can balance the development of ecotourism with wildlife conservation, contributing significantly to the coordinated development of economic, social, and environmental objectives.

Climate change's influence on Chelydra serpentina's global and Chinese distribution and invasion: A MaxEnt model-based prediction

Chelydra serpentina (Linnaeus, 1758) is native to North America, but has been introduced to numerous nations and is now globally spread. It is extremely adaptive, grow quickly, and its biological population is steadily increasing as a result of the development of aquaculture technology. Given that Chelydra serpentina has already been found alive in the natural ecosystems of China, its proliferation poses a possible threat of invasion. Using the global distribution data of the species in the current environment, a study was carried out to forecast the distribution trend of Chelydra serpentina under future climate circumstances. The study compared the changes in the distribution area under current climatic circumstances and the tendency of proliferation using 19 bioclimatic factors and the ecological niche model Maxent. Using the significance index, the study also examined the size of the appropriate region and the influencing factors to estimate the danger of Chelydra serpentina invasion better quantitatively. In our research, we hypothesized that forthcoming climate change will affect the geographical distribution of Chelydra serpentina. The study results showed that, even in high-intensity environments, the appropriate area for Chelydra serpentina will steadily increase in the future climate. The extent of their suitable habitat might expand (the highly suitable area: 7.42*105 km2 <China>; 2.13*107 km2 <Global>) in contrast to the distribution area of Chelydra serpentina under the existing climate (highly suitable area: 6.01*105 km2 <China>; 8.48*106 km2 <Global>). The research findings indicate that the range of the habitat area predicted to proliferate (the highly suitable area of 6.31*105 km2 <China>; 1.3 *107 km2 <Global>) even in high-intensity environments, albeit at a slower rate than in the low-intensity environment model. The habitat will initially be concentrated in warmer regions before progressively expanding into the colder northern climate. This implies that Chelydra serpentina will be able to more easily adjust to future climates and spread outward over time from its concentrated home. Nonetheless, there is a chance of an invasion due to the rise in Chelydra serpentina populations. Upon establishing a regular reproductive presence in the Chinese waterways they inhabit, these turtles will engage in fierce competition with indigenous species for survival, posing a threat to the environment and potentially resulting in the extinction of some local species.

Restorative function of offshore longline mussel farms with ecological benefits for commercial crustacean species

Offshore ocean aquaculture is expanding globally to meet the growing demand for sustainable food production. At the United Kingdom's largest longline mussel farm, we assessed the potential for the farm to improve the habitat suitability for commercially important crustaceans. Modelled distribution patterns (GAM & GLM) predicted the low complexity seabed beneath the mussel farm was 34–94 % less suitable for European lobster (Homarus gammarus) and brown crab (Cancer pagurus) than nearby rocky reefs. The mussel farm operations, however, contributed large amounts of living mussels and shell material to the seabed. Acoustic telemetry revealed that H.gammarus remained within the farm for between 2 and 283 days using both the farm anchors and areas of seabed dominated by fallen mussels for refuge. In contrast, C. pagurus movements showed no affinity to either the farm infrastructure or benthic habitat under the farm. Stable isotope analysis indicated a high dietary niche overlap in C. pagurus and H. gammarus (67.8 and 84.6 %) between the mussel farm (mixed muddy sediment) and nearby rocky reef. Our mixed-methods suggest that the mussel farm augments structural complexity on the seabed providing refuge and similar feeding opportunities for lobster and crab as their typical habitat on rocky reefs. Longline mussel farms can deliver profound biodiversity-positive effects through biogenic augmentation of degraded habitat for commercial species and potential for co-benefits to local fisheries.

Dataspace Integration for Agrobiodiversity Digital Twins with RO-Crate

A severe impact of human-induced climate change is the global decrease in crop yields, threatening the United Nations sustainable development goal (SDG) to end hunger, achieve food security, improve nutrition, and promote sustainable agriculture (SDG 2: “Zero Hunger Goal”). Decision-making on appropriate mitigation strategies requires data integration from heterogeneous data-rich contexts including Earth observation (EO), biodiversity monitoring, gene banks as well as socio-economic data. Accordingly, large-scale initiatives for thematic data spaces, such as the European projects Destination Earth (DestinE) and the Green Deal Data Space, have been launched. Underutilized crops and crop wild relatives (CWR) can contribute to mitigating the impacts of climate change since their greater genetic diversity allows adaptation of agro-food sources to extreme weather events such as flooding and drought or emerging crop pests. Within the framework of Biodiversity Digital Twin (BioDT), a prototype digital twin for crop genetic resources modeling is under development. This prototype combines the scanning of genetic resources of CWRs and traditional cultivars for promising pest resistance and abiotic tolerance traits with advanced species distribution modeling and actual climate scenarios from EO. The aim is to generate habitat suitability maps and identify potential areas where relevant populations are potentially growing (Chala et al. 2024). The talk gives an overview of data models used to facilitate the required interoperability of both Earth models and environmental data within and across different data spaces such as the DestinE Data Lake (Duatis Juarez et al. 2023). Based on our findings from the use case of agrobiodiversity digital twins, we will discuss approaches for processing machine-actionable digital objects (Fig. 1) containing workflow information (i.e., in the Common Workflow Language format, Crusoe et al. 2022), and for sharing resulting research data in a FAIR (Findable, Accessible, Interoperable, and Reusable) manner by leveraging on so-called webby FAIR Digital Objects involving Research Object Crate (RO-Crate, Soiland-Reyes et al. 2022), FAIR Signposting (Soiland-Reyes et al. 2024) and schema.org and its Bioschemas extension respectively (Castro et al. 2020),

Predicting climate change impact on the habitat of Ethiopia’s spot-breasted lapwing using ensemble model

Endemic species are usually confined in a restricted geographical range with specialized ecological requirements. Majority of these species, therefore, are under the risk of extinction due to climate change coupled with other anthropogenic pressures. The impact is increasingly recognized as severe in tropical highland endemic bird species by either shifting or contracting their geographical range. In this study, we tried to show the impact of climate change on one of Ethiopian highland endemic bird species, the spot-breasted lapwing (Vanellus melanocephalus). Although this species is considered Least Concern, it is restricted in the fragmented Afro-alpine open grassland a long streams or seasonal pond ecosystem of Ethiopia. We predicted the current suitable habitat of this species and projected its future suitable habitat range under two shared socio-economic pathways (SSP4.5 and SSP8.5) of the year 2050 and 2070. We used 117 georeferenced occurrence points and 11 ecologically important variables to develop an ensemble suitable habitat modeling by averaging nine-species distribution algorithms with threshold of TSS > 0.7. The result indicated 104,117.62 km² area as a predicted suitable habitat range in various northwestern and southeastern Ethiopian highlands. The largest range of this suitable habitat (78.02 %) is outside the protected areas of the country. Mean temperature of the driest quarter was the leading bioclimatic variable for the prediction of suitable habitat of this species followed by iso-thermality and vegetation. Habitat suitability declined as mean temperature of the driest quarter is beyond 15ºC. Under future climatic scenarios, substantial suitable habitat loss will occur with more than 50 % of net range size change. This loss of suitable habitat will be 86.60 % under SSP8.5 by the year 2070. Such range contractions suggest the potential risk of extinction of this species in the future unless conservation action is taken. The presence of a large range of current suitable habitat outside of protected areas reveal the need for species-specific conservation plan in both protected and unprotected areas. Moreover, adequate ecological, genetic and geographical studies are also mandatory to have full understanding regarding the impact of climate change and anthropogenic pressure on this endemic bird species in the future.

Cryptic species diversity and contrasting climate profiles in Aotearoa New Zealand, egg‐laying and live‐bearing velvet worms (Onychophora, Peripatopsidae: Ooperipatellus and Peripatoides)

AbstractAotearoa (New Zealand) is a biodiversity hotspot for temperate invertebrate taxa and home to high levels of endemicity. However, our knowledge of species‐level diversity and phylogeny of endemic New Zealand Onychophora (velvet worms) is at present limited. Here, we use mitochondrial cytochrome c oxidase subunit I (COI) barcoding to assess the extent of species diversity for the two velvet worm genera found in New Zealand, the ovoviviparous and endemic Peripatoides and the oviparous Ooperipatellus, found in Australia and New Zealand. Our results reveal that the estimated number of species of both genera in New Zealand is greater than currently described. We estimate there are between 13 and 67 species of Peripatoides and between 16 and 21 species of Ooperipatellus endemic to New Zealand. This is a stark increase from the two currently described New Zealand species of Ooperipatellus and previous work that has identified 10 species within Peripatoides. Our exploration of climatic variables shows that individuals of Ooperipatellus are predominantly found in wet, cool environments and Peripatoides are found across relatively drier, warmer habitats. We also generate ecological niche models to provide initial predictions of the distribution of climatically suitable habitats for each genus across New Zealand.

Predicting habitat suitability for the soybean pod borer Leguminivora glycinivorella (Matsumura) using optimized MaxEnt models with multiple variables.

The soybean pod borer Leguminivora glycinivorella (Matsumura) is one of the most important soybean pests and often causes serious damage to Glycine max (L.) Merr., a leading source of dietary protein and oil in animal feed. However, the potential distribution patterns of this economically important pest and its driving factors require further investigation. Here, we used the optimized MaxEnt model to predict the potential distribution of this pest with multiple variables associated with climate, land use, and host plant, at its recorded range and a globe scale. Based on 4 variable combinations, the results show that the current suitable habitats of L. glycinivorella are primarily distributed in most of China, the Korean Peninsula, and Japan. Whereas no suitable area is present in other continents. In future projections, the suitable region shows a slight northward expansion compared with the result predicted with current climatic conditions, and the suitable areas of almost all future projections were stable in size. Among the 9 bioclimatic factors, BIO03 (isothermality) consistently highly contributes to the predictions, indicating that temperature may be a key factor influencing the habitat distribution of L. glycinivorella. Comparative analyses of projections further show that non-climatic factors are informative in the modeling as routinely used bioclimate variables. The spatio-temporal distribution patterns of suitable habitats and the regulatory factors predicted in this study could provide important guidance for L. glycinivorella management.

Whole genome resequencing reveals the evolutionary history and geographic isolation of the eastern Asian Hickory (Carya)

Societal Impact StatementUnraveling the genetic intricacies and evolutionary history of Asian Hickories through advanced genome sequencing gives valuable insights into their ecological adaptations. Understanding the impact of historical dynamics, climate fluctuations, and geographical barriers on Asian hickories not only contributes to scientific knowledge but also empowers policymakers with evidence‐based decisions and guides conservationists in their efforts to protect vulnerable species. The identification of potential habitats, especially for the endangered Carya kweichowensis, offers a promising avenue for targeted conservation efforts, aligning with global initiatives to preserve Earth's precious biodiversity, but also ensures the conservation of a vital genetic reservoir for nut‐bearing economic tree species.SummaryBiogeographic characteristics of disjunct distribution play a vital role in plant geography and the endangered mechanism. The whole genome resequencing provides an opportunity to study the genetic relationship, population diffusion, and floristic evolution of disjunctive‐distribution flora. Based on the SNPs (single nucleotide polymorphisms) data generated by the whole genome deep resequencing of five EA (Eastern Asian) Carya species, we constructed the phylogenetic tree, genetic structure, and species distribution modeling to clarify the phylogenetic relationships and to predict the potential distribution area of EA Carya. Phylogenetic analysis of Carya revealed two distinct clades, separating EA Carya from NA (North America) Carya. C. kweichowensis, an endangered species, showed the lowest nucleotide diversity and the earliest divergence among studied EA Carya species. Species distribution modeling predicted suitable habitats for five EA Carya species, revealing the potential distribution of endangered C. kweichowensis. Importantly, minimal spatial overlap was observed among distribution regions of EA Carya species during different time periods. The uneven regional distribution of EA Carya is believed to be a consequence of Quaternary climate fluctuations, mountain barriers hindering species dispersal, and the limited cold tolerance of these trees. EA Carya highlights the significant role of climate and geological changes in their regional distribution and migration routes in Asia. Furthermore, the discovery of potential habitats offers a promising avenue for the conservation of C. kweichowensis.

Habitat connectivity drives panda recovery

Globally, the majority of habitat loss is irreversible, and most species will never recover their former ranges. We have learned a great deal about what leads to population decline and extinction, but less about recovery. The recently downlisted giant panda provides a unique opportunity to understand the mechanisms of species recovery. In our study, we estimate giant panda suitable habitats, population density, and gene flow across landscapes to fully investigate the direct and indirect ecological mechanisms underlying bold conservation strategies. We found that the Giant Panda National Survey has modestly but systematically underestimated population size. China's effort to mitigate anthropogenic disturbances was associated with increased panda population density through improving habitat quality and reducing habitat fragmentation. Enhanced landscape connectivity reduced inbreeding via gene flow but indirectly increased inbreeding temporarily due to high local panda density. Although the panda's recovery has been geographically uneven, we provide evidence for improving connectivity and gene flow resulting from conservation efforts. If these processes can be sustained and improved, the panda's path to recovery will be less encumbered by loss of genetic diversity, fostering hope that the present rate of recovery will not be stalled. Findings from this study will not only help guide future giant panda conservation management but also provide a model for how a more mechanistic examination of the genetic processes underlying species recovery can foster the development of more effective strategies for endangered species recovery.

New species of Salicaceae with opposite leaves from the Atlantic Forest, Brazil

Abatia mantiqueirensis is described and illustrated as a new species with distribution for the Brazilian states of Minas Gerais and Rio de Janeiro. It is morphologically similar to A. americana but can be distinguished by the presence of canaliculated petiole, acute serrate leaf margin, glands at the apex of the margin serrations that are rounded to concave and projected outwards from the leaf blade, upper portion of the pedicel winged and seeds with tiny dorsal wings. Taxonomic description, comments, and geographical distribution information are here in provided. So far, only three populations of A. mantiqueirensis are known with only one of them recorded in a protected area. Based on the availability of suitable habitats, possible threats and future potential geographical distribution, we propose the conservation status for A. mantiqueirensis as Critically Endangered.

Minimum environmental flow assessment: a fuzzy TOPSIS decision-making system for selecting the best approach

The literature has explored various methods for assessing minimum environmental flow. Implementing holistic approaches proves to be prohibitively expensive and impractical for many small and medium projects. Hence, desktop and cost-effective methods are commonly employed without an integrated decision-making system to justify the assessed values. This study introduces a systematic decision-making framework aimed at selecting the most suitable method for assessing the actual needs of river habitats. Employing a fuzzy technique known as the Order Preference Similarity to the Ideal Solution (FTOPSIS), the study considers factors such as physical, thermal, and dissolved oxygen habitat suitability, maximum habitat area, and water demand loss function to determine the most appropriate method among established ones, including the Tennant method, flow duration curve analysis method, wetted perimeter method, and physical habitat simulation method. The results prioritize physical habitat simulation, wetted perimeter by slope method, and flow indices of 70%, 75%, and 80% by flow duration curve analysis method as the optimal approaches for assessing minimum environmental flow. This proposed decision-making system offers a viable platform to explore the applicability of existing cost-effective methods for assessing minimum environmental flow. It also serves as an effective mechanism for reducing negotiations among stakeholders by comprehensively considering all relevant aspects in the environmental management of river ecosystem requirements.

Suitable Habitat Distribution and Niche Overlap of the Sable (Martes zibellina) and Yellow-Throated Marten (Martes flavigula) in Taipinggou National Nature Reserve, Heilongjiang Province, China.

The global focus on fostering harmonious interactions and promoting rational coexistence among wildlife species to uphold or reinstate biodiversity remains a prominent area of interest. We conducted a study on the sable and yellow-throated marten in Taipinggou National Nature Reserve, Heilongjiang, China, using the line transect method and infrared camera traps from 2022 to 2023. We then analyzed the overlap of their suitable habitats and niches with the aim of gaining insight into the interspecific competition between these two species. We found that the suitable habitat areas for the sable and yellow-throated marten were 55.20 km2 and 23.28 km2, accounting for 24.86% and 10.48% of the total area of this study, respectively. The overlap between the suitable habitats for the sable and yellow-throated marten was 15.73 km2, accounting for 28.5% and 67.6% of their suitable habitat, supporting our Hypothesis 1. The first principal component (Dim1) of the niche explained 35.4% of the overall variability, which is mainly related to the environmental variables "Distance from Settlements" and "Distance from Roads". Overall, 25.5% of the total variability was explained by the second principal component (Dim2), associated with "Slope" and "Distance from Coniferous and Broadleaved Mixed Forest". The niches occupied by the sable and yellow-throated marten were both off-center of the environmental background space, with the niches of the sable being larger than those of the yellow-throated marten. Schoener's D index was 0.56, indicating a high degree of niche overlap between the sable and yellow-throated marten, supporting our Hypothesis 2. Our study is helpful in terms of formulating conservation and management policies for the sable and yellow-throated marten.

Modeling the distribution of hemlock woolly adelgid under several climate change scenarios

The hemlock woolly adelgid (HWA), Adelges tsugae Annand, has invaded eastern North America and caused significant mortality to eastern hemlock, Tsuga canadensis (L.) Carrière. In eastern North America, HWA’s range is theorized to be limited by minimum winter temperatures. As climate change reduces the severity of winter, the risk of northward expansion of HWA increases. This study used maximum entropy species distribution modeling in conjunction with HWA occurrence records and future climate projections to model habitat suitability for HWA throughout the range of eastern hemlock. Species distribution models were created for present and future climatic conditions using both historical climatic data and future climatic emissions scenarios for mid- and late-century. In addition, present climatic condition reference models for western North America and Asia were generated for comparison with HWA’s current range and earlier predictions of the potential range in eastern North America. Under a low emissions scenario, HWA will be capable of invading almost the entire range of eastern hemlock by the end of the century. More extreme warming scenarios result in a more rapid northwards shift by mid-century. The consequences for eastern hemlock are significant, with infestations likely to become more widespread and severe due to climate change.