Distribution Of Suitable Habitat Research Articles

Climate change impacts on optimal habitat of Stachys inflata medicinal plant in central Iran

Stachys inflata Benth. is a perennial shrub plant, with powerful natural antioxidant agents, which is recognized as a famous medicinal plant that is widely applied to treat Infection, Asthma, and Rheumatism. Iran is renowned as a center of diversity for Stachys, however, the ideal habitats of S. inflata in this nation remain unknown. The potential and future distribution of suitable habitats for S. inflata were projected using an ensembles ecological niche model in Isfahan province, Iran. We used occurrence data (using GPS), bioclimatic and topographic variables from the Chelsa and WorldClim databases to model the current and future potential distribution of this valuable species. The results showed that: (i) S. inflata is mainly distributed in the south, southwest, center, and west of the Isfahan province, and the excellent habitats of S. inflata accounted for 14.34% of the 107,000 km2 study area; (ii) mean annual temperature, mean daily temperature of wettest quarter, annual precipitation, and elevation were the four most important variables that affect the distribution of S. inflata, with a cumulative contribution of 56.55%; and (iii) about the half (− 42.36%) of the currently excellent habitats of S. inflata show a tendency to decrease from now to the 2080s, while often the area of other S. inflata habitats increases (the area of unsuitable habitat: 5.83%, the area of low habitat suitability: 24.68%, the area of moderate habitat suitability: 2.66%, and the area of high habitat suitability: 2.88%). The increase in the area of other S. inflata habitats is different and they are less favorable than the excellent habitat. The results help establishing a framework for long-term in-situ and ex-situ conservation and management practices in habitats of S. inflata in rangeland and agricultural ecosystems.

Predicting Impacts of Climate Change on Teak and Sal Forests in Central India Using Maximum Entropy Modeling: an Approach for Future Conservation and Silvicultural Strategies

Abstract Climate change impacts on tropical forests and tree species have been documented as changes in distribution, growing period, phenology, habitat, productivity, species composition, and migration. This study attempts to assess the current and future habitat suitability distribution of two dominant species of Central India, teak (Tectona grandis Linn. f.) and sal (Shorea robusta Gaertn. f.) using a maximum entropy (MaxEnt) model to predict species occurrences by finding the distribution that has the most spread. The future suitable habitat ranges of the species were modeled for two time periods (2050 and 2070) and two representative concentration pathways (RCP 2.6 and 8.5). Representative concentration pathways are scenarios that describe alternative trajectories for carbon dioxide emissions and the resulting atmospheric concentration from 2000 to 2100. We collected and modeled the spatially well-dispersed species occurrence points of teak and sal. The results suggested an increase in suitable habitat range for teak and a decrease for sal for both time periods and RCPs. Furthermore, the jackknife analysis identified temperature and precipitation seasonality as the major variables that influence the distribution of teak. In the case of sal, minimum temperature makes the maximum contribution to distribution changes. The suitable silvicultural strategies for forest management are proposed based on the future distribution of species in relation to the climate variables responsible for the change in their distribution range. These findings and strategies will help forest departments build future management plans for teak and sal forest with a focus on minimizing the impact of climate change. Study Implications: Our study used maximum entropy (MaxEnt) modeling to understand the impact of changing climate on the distribution of teak and sal forests of central India and to propose future silvicultural strategies. The study used MaxEnt model for two time periods and two climate change scenarios at highest resolution. An increase in future suitable habitat for teak and a decrease for sal is predicted by the model. Temperature for teak and precipitation for sal were identified as the major influencing climatic variables. We recommend forest and other related government departments to commission focused research to understand the changing patterns of species with climate change and design appropriate silviculture strategies for effective management.

Permeability of coastal biogeographic barriers to marine larval dispersal on the east and west coasts of North America

AbstractAimWe assess the role of contemporary oceanography and species traits in shaping observed patterns of biogeography over broad spatial scales.LocationOur study domain covers the east and west coasts of North America, from 30° to 73° N on the east coast and 33° to 73° N on the west coast.Time periodHydrodynamic models use climatological fields from 1990 to 2015 on the east coast, and 1993 to 2018 on the west coast.Major taxa studiedModel simulations represent larval dispersal for generalized benthic invertebrate species distributed in the subtidal zone from 10 to 100 m depth, with planktonic larval durations ranging from 21–60 days.MethodsWe conducted a literature review to identify major biogeographic barriers along the east and west coasts of North America, and then assessed the permeability of these barriers to larval dispersal using Lagrangian particle tracking. We ran a series of simulations in which we varied the suitable habitat distribution, planktonic larval duration, and spawning seasonality of simulated larvae (i.e., particles) to assess the effects of species traits on biogeography.ResultsOur results showed a strong alignment of observed biogeographic barriers with larval dispersal patterns, with high variation in barrier permeability depending on the traits of the species considered. The location of suitable habitat and the season during which particle release occurred were the biological traits that drove much of the variation in barrier permeability among simulations on both coasts.Main conclusionsOur results indicate an important role of contemporary oceanographic and geographic features in determining the biogeography of species whose primary dispersal is during larval stages, suggesting that climate change is likely to alter patterns of species biogeography. Our results also demonstrate that species traits play a strong role in determining the location and strength of biogeographic barriers.

Modeling Suitable Habitats of Indo-Pacific Humpback Dolphins (Sousa chinensis) in a Highly Urbanized Bay

Indo-Pacific humpback dolphins (Sousa chinensis) live in coastal waters that have experienced considerable anthropogenic disturbances. Specifically, along the coasts of highly urbanized regions, available habitats have decreased in both space and scale. This study used Maxent software to simulate the distribution of suitable habitats for S. chinensis during the dry and wet seasons in Xiamen Bay. We also aimed to identify key environmental factors influencing habitat distribution, with the goal of using our results to analyze conservation gaps and propose adjustments. We found that during the dry season, S. chinensis were mainly distributed in the Western Harbor, Jiulong River Estuary, and the mouth of Tongan Bay. During the wet season, they were distributed in the south of Western Harbor, Jiulong River Estuary, and around the Wuyu and Dadeng-Xiaodeng Islands. Nekton density, chlorophyll-a concentration, sea surface temperature, slope, and salinity are the primary factors affecting S. chinensis distribution in Xiamen Bay. To better protect the species, the existing Tongan Bay reserve should be expanded during dry seasons, and suitable habitats in the Jiulong River Estuary should be turned into a seasonal protected region. Similarly, during wet seasons, the original Western Harbor portion of the reserve should increase to include the Jiulong River Estuary, northwest of the Wuyu Islands and south of the Dadeng-Xiaodeng Islands. In addition to this dynamic seasonal management of reserve size, we also recommend developing multiple-use protected areas and establishing a joint protection mechanism between local governments. In conclusion, our model offers important guidance on improving conservation measures of S. chinensis in Xiamen Bay.

Habitat suitability and potential biological corridors for waterbirds in Yancheng coastal wetland of China

Yancheng coastal wetland, as an important part of the East Asian–Australasian Flyway, provided habitat for more than 200 migratory waterbirds by rest and over-winter. After it was listed as a “World Heritage List” in 2019, the protection of waterfowl habitat in Yancheng coastal wetland has attracted extensive attention from the international community. As an indicator species of Yancheng coastal wetland ecosystem health, waterbirds have practical significance for the protection of Yancheng coastal wetlands. Due to the long-term impact of human activities, the waterbird habitats are facing the threat of habitat fragmentation and lose, posing a serious challenge to its survival and diversity. Based on the survey data obtained Gruiformes, Charadriiformes, and Anseriformes waterbirds during the whole years from 2017 to 2021, this paper used the Maxent software for modeling species niches and distributions, a comprehensive evaluation method based on fuzzy mathematics, and Linkage Mapper model to assess the habitat suitability distribution of waterbirds, identify protection gaps and potential biological corridors for waterbirds in Yancheng coastal wetland. The results showed that habitat suitability and anthropogenic disturbance were the decisive factors affecting habitat selection of waterbirds. The suitable habitats for Gruiformes, Charadriiformes, and Anseriformes waterbirds were 23868, 22670, and 24870 ha, respectively. The suitable habitat area of waterbirds was 121,930 ha, concentrated on the study area's central and southern coast. Sheyang estuary was identified as a vital conservation gap in the study area. Meanwhile, biological corridors of a total of 33 waterbirds were identified in the study area. The longest biological corridor was 18.78 km, and the shortest was 0.09 km. Our research can provide scientific support for Yancheng coastal wetland protection and the improvement of waterbird diversity, together with the achievements of an ecological and sustainable situation between environmental conservation and economic development.

Planning Ginkgo biloba future fruit production areas under climate change: Application of a combinatorial modeling approach

Ginkgo biloba forests are widely studied for their fruits’ high medicinal, edible, and economic values with an increasing global demand for its fruits supply. The impact of climate change on the habitat suitability of this species has been assessed in previous studies. This study was to address the climate change impact on both habitat suitability and fruit yield. We used fruit grain weight to represent fruit productivity and quality of Ginkgo fruit forests and related it to climate variables to develop a climate response function (Method I). Meanwhile, we also built a Maxent habitat suitability model and associated it with fruit grain weight (Method II). Results showed that Method I provided much higher prediction accuracy (R2 = 0.68) than Method II (R2 = 0.39). We combined Method I with the species habitat model to predict suitable production areas of Ginkgo fruit to achieve high fruit production within suitable habitats for the contemporary and future periods. We found that Ginkgo fruit grain weight was mainly affected by mean annual average temperature (MAT) and mean annual precipitation (MAP), while the degree-days below 0 ℃ (DD < 0) was the main climate factor limiting the distribution of Ginkgo fruit forests suitable habitat. The combined model predictions showed that the suitable production areas of Ginkgo fruit forests are expected to decrease and move northeastward in the future under the Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. Our predictions can be used to maximize Ginkgo fruit quality production while minimizing the risk of low survival in the planning of Ginkgo fruit forest production areas.

Prediction of Changes to the Suitable Distribution Area of Fritillaria przewalskii Maxim. in the Qinghai-Tibet Plateau under Shared Socioeconomic Pathways (SSPs)

The Qinghai–Tibet Plateau has given birth to many indigenous highland plants due to its special geographical location and sensitivity to climate change. Relevantly, the impact of climate change on species distribution has been a hot issue for research in biogeography. Using the maximum entropy (MaxEnt) model, the spatial distribution of habitat suitability for Fritillaria przewalskii Maxim. (FPM) on the Tibetan Plateau was predicted and ranked by combining ecological data and information on its actual current geographical distribution. The potential distribution and trends of FPM on the Tibetan Plateau from 2021 to 2040, 2041 to 2060, 2061 to 2080 and 2081 to 2100 under four current and future climate scenarios (SSP126, SSP245, SSP370 and SSP585) were also predicted. The predictions were found to be highly accurate with AUC values of 0.9645 and 0.9345 for the training and test sets, respectively. A number of conclusions could be drawn from the results. Firstly, the main ecological factors limiting the growth distribution of FPM were the Vegetation types, NPP (net primary production), Soil types, Bio7 (temperature annual range), Pop (population), Slope, GDP, Aspect, Bio1 (annual mean temperature) and Elevation, with a cumulative contribution of 97.6%. Secondly, in the recent past period of 1970–2000, the total suitable distribution area of FPM accounted for 5.55% of the plateau’s total area, which was about 14.11 × 104 km2, concentrated in its eastern and central regions. Thirdly, compared to the previous period, the aforementioned distribution area will, for the period spanning 2021–2040, increase by 14.48%, 16.23%, 16.99%, and 21.53% in the SSP126, SSP245, SSP370, and SSP585 scenarios, respectively. This comes with an overall expansion trend, and the areas predicted to be affected are concentrated in the eastern and central-western parts of the Tibetan Plateau. The other three future periods 2041–2060, 2061–2080, and 2081–2100 also show increases in these total areas to varying degrees. It is noteworthy that in the future periods 2061–2080 and 2081–2100, under the SSP370 and SSP585 scenarios, the area of high suitable distribution decreases or even disappears. Lastly, under the four climate scenarios, the FPM suitable distribution area will shift towards the western part of the Tibetan Plateau.

Seasonal change of habitat selection of Hydropotes inermis in Yancheng coastal wetlands, China

Yancheng coastal wetlands are one of the main habitats and breeding grounds of wild Chinese water deer (Hydropotes inermis). Based on GPS-GSM tracking data, we used the habitat selection index and MaxEnt model to simulate and analyze the distribution of suitable habitat of H. inermis in different seasons as well as the main influencing factors. The results showed that H. inermis mainly used reed marshes, with the usage rate in spring-summer and autumn-winter being 52.7% and 62.8%, respectively. The area under receiver operating characteristic curve value simulated by MaxEnt model in different seasons was 0.873 and 0.944, which showed high prediction accu-racy. In spring and summer, the sub-suitable and most suitable habitats were mainly reed marshes, farmland, and ponds. In autumn and winter, the main habitat types were reed marshes and ponds, with an area equivalent to only 5.7% and 8.5% of that in spring and summer. Distance to reeds, distance to Spartina alterniflora, habitat types, distance to water and distance residential area were the main environmental variables affecting the distribution of H. inermis in spring and summer. The above five variables and vegetation height were the main environmental variables affecting the distribution of H. inermis in autumn and winter. This study would provide an important reference for the conservation of Chinese water deer and the fine management of their habitats in Yancheng coastal wetlands.

Spatial dynamic simulation of important cash crops based on phenology with Scutellaria baicalensis Georgi as an example

Substantial differences in the niche and quality of plants, especially in cash crops, are clearly observed in different phenological phases. Many plants have distinct phenological characteristics, yet the distribution patterns and secondary metabolites in plants at different growth stages are poorly understood. We examined the importance of environmental variables in phenological phases for plant niches and quality using 30 years of species spatial occurrence point data combined with phenological data and other environmental factors. First, we developed niche models for Scutellaria baicalensis Georgi to estimate the distributions of habitat suitability and spatial dynamics for five developmental stages. Our results suggested that some populations were lost when environmental factors in specific phenological stages were involved in modeling and that these environmental variables contributed more than 30 % of the total to species distribution modeling. The results of independent phenological niche modeling illustrated the spatial variation dynamics of S. baicalensis, and 22.88 % of the potential distribution areas were consistent among the five phenological periods. Additionally, we considered the impact of environmental variables in five growth stages on quality. Six environmental variables (maximum temperature during the flowering period, maximum temperature during the blooming period, maximum temperature during the fruiting period, phenological precipitation during the fruiting period, precipitation standard deviation during the fruiting period, and phenological precipitation during the withering period) played pivotal roles in the formation of secondary metabolites and affected the spatial distribution of plant quality. Our study demonstrates the importance of phenological phases and highlights that they should be considered if plants have distinct phenological signatures. In regard to cultivation and management, our results provide decision-makers with an integrative approach for planning the rational allocation of resources used to obtain medicinal plants.

Modelling the Geographical Distribution Pattern of Apple Trees on the Loess Plateau, China

The Loess Plateau, known for its fragile ecosystems, is one of the traditional apple-producing regions in China. Although some management measures are needed to enhance sustainable agriculture in response to the rising pressure of climate change, the geographic distribution of apple trees considering multiple variables has not been considered. In this study, we used three software (the maximum entropy model, IDRISI, and ArcGIS) to simulate the potential distribution of suitable habitats and range shifts of apple trees in the near present and near future (i.e., the 2030s and the 2050s) under two climate scenarios (the Shared Socioeconomic Pathways (SSP)1-26 and SSP5-85), while taking a variety of environmental factors into account (e.g., temperature, precipitation, and terrain). After optimization, the class unsuitable habitat (CUH) changed the potential distribution pattern of apple trees on the Loess Plateau. Currently, the areas of lowly suitable habitat (LSH), moderately suitable habitat (MSH), highly suitable habitat (HSH), and CUH were 7.66 × 104, 2.80 × 104, 0.23 × 104, and 18.05 × 104 km2, respectively. Compared to the centroid estimated under the climate of 1970–2000, the suitability range of apple trees was displaced to the northwest in both the 2030s and the 2050s in SSP5-85 (i.e., 63.88~81.30 km), causing a larger displacement in distance than SSP1-26 (i.e., 40.05~50.32 km). This study demonstrates the possible changes in the spatial distribution of apple trees on the Loess Plateau in the near future and may provide a strong basis for future policy making.

Assessment of habitat suitability and connectivity across the potential distribution landscape of the sambar (Rusa unicolor) in Southwest China

Habitat suitability assessment is the basis for wildlife conservation management and habitat restoration. It is a useful tool to understand the quality of wildlife habitat and its potential spatial distribution. In order to reveal the habitat suitability and connectivity of sambar (Rusa unicolor) to promote species and biodiversity conservation, this study collected records of sambar (Rusa unicolor) from over 2,000 camera traps in the forests of Southwest China in the past 5 years to assess the overall situation of their habitat. The results of the species distribution model revealed that the suitable habitat area for sambar in the five major mountain ranges (Minshan, Qionglai, Daxiangling, Xiaoxiangling, and Liangshan) in Southwest China is 18,231 km2, accounting for 17.02% of the total area. The most suitable habitat of sambar is primarily distributed in Qionglai, as well as the intersection areas of Daxiangling, Xiaoxiangling, and Minshan. The temperature annual range, temperature seasonality, elevation, and distance to road were important factors affecting the distribution of suitable habitat for sambar. Analysis of landscape pattern shows that there were 273 habitat patches, with a maximum patch area of 9,983 km2, accounting for 54.8% of the total suitable habitat area. However, the segmentation index and separation index of each habitat patch were 0.99 and 106.58, respectively, indicating a relatively high habitat fragmentation in the study area. The results of habitat connectivity analysis showed that the Qionglai mountains have the largest suitable habitat area and the highest connectivity among habitat patches. However, habitat connectivity between the five mountains is very low, suggesting that gene flow among these mountain ranges is probably limited. We therefore recommend strengthening protection of sambar and their habitat, with special attention to the establishment of corridors between the different mountain populations.

Predicting Mangrove Distributions in the Beibu Gulf, Guangxi, China, Using the MaxEnt Model: Determining Tree Species Selection

Mangrove restoration is challenging within protected coastal habitats. Predicting the dominant species distributions in mangrove communities is essential for appropriate species selection and spatial planning for restoration. We explored the spatial distributions of six mangrove species, including their related environmental factors, thereby identifying potentially suitable habitats for mangrove protection and restoration. Based on six dominant mangrove species present in the Beibu Gulf, Guangxi, China, we used a linear correlation analysis to screen environmental factors. In addition, we used the maximum entropy model to analyze the spatial distributions of potential mangrove afforestation areas. Based on the spatial superposition analysis, we identified mangrove conservation and restoration hot spots. The findings indicate that topographic and bioclimatic factors affect the distribution of suitable mangrove habitats in the Beibu Gulf, followed by land use type, salinity, and substrate type. We identified 13,816 hm2 of prime mangrove habitat in the Beibu Gulf that is primarily distributed in protected areas. The protection rate for existing mangroves was 42.62%. According to the predicted spatial distributions of the mangrove plants, the findings suggest that mangrove restoration should be based on suitable species and site selection.

The current and future seasonal geographic distribution of largehead hairtail Trichiurus japonicus in the Beibu Gulf, South China Sea

Largehead hairtail Trichiurus japonicus is a major commercial fish species in the Beibu Gulf of the northwestern South China Sea. Despite much effort to protect the fishery resource, the current stock of T. japonicus is overexploited. As the impacts of climate change unfold globally, seasonal changes in the distribution of largehead hairtail in the Beibu Gulf have not yet been clarified. Maximum entropy model based on mixed layer depth and salinity were projected onto seasonal habitat changes of T. japonicus in the Beibu Gulf under a current scenario and three different Representative Concentration Pathways (126, 370, 585) to evaluate geographic distribution changes under the different climate-change scenarios. The current geographic distribution results showed variation with seasonality, as the wintering population shifts toward the northeast. Under each of three SSP scenarios, there is higher risk to habitat suitability in the 2090s as compared with that in the 2050s. The disadvantage to T. japonicus distribution is greatest in winter under each of the three climate change scenarios, both in the short- and long-term. Potential suitable habitat distributions have a minor range extension in Representative Concentration Pathway 370–2050 winter, but in the rest of the scenes and years they contract to south of the Beibu Gulf. The overall results indicate that seasonal differences in suitable habitat should be considered to ensure effective planning of future management strategies for T. japonicus.

Predicting the distributions of Pouteria adolfi‐friederici and Prunus africana tree species under current and future climate change scenarios in Ethiopia

AbstractDistributions of potential ranges of plant species are not yet fully known in Ethiopia where high climatic variability and vegetation types are found. This study was undertaken to predict distributions of suitable habitats of Pouteria adolfi‐friederici and Prunus africana under current and two future climate scenarios (RCP 4.5 and RCP 8.5 in 2050 and 2070) in Ethiopia. Eleven environmental variables with less correlation coefficients (r &lt; 0.7) were used to make the prediction. Shifting in extents of habitat suitability and effects of elevation, solar radiation and topographic position in relation to the current and future climatic scenarios were statistically analysed using independent t‐test and linear model. We found decreasing area of highly suitable habitat from 0.51% to 0.46%, 0.36% and 0.33%, 0.24% for Prunus africana and 1.13% to 1.02%, 0.77% and 0.76%, 0.60% for Pouteria adolfi‐friederici, under RCP 4.5 and RCP 8.5 by 2050 and 2070 respectively. Moist and dry afromontane forests are identified as the most suitable habitat for both species. Overall, our results suggest that climate change can promote dynamic suitable habitat niches under different future climate scenarios. Therefore, biodiversity conservation strategies should take into account habitat suitability dynamics issues and identify where to conserve species before implementing conservation practices.

海草床种子扩散过程及种子库形成机制研究进展

PDF HTML阅读 XML下载 导出引用 引用提醒 海草床种子扩散过程及种子库形成机制研究进展 DOI: 10.5846/stxb202108262396 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划(2019YFE0121500);国家自然科学基金委-山东联合基金(U2006215);唐仲英基金会 A review on seed dispersal process and mechanism of seed bank formation of seagrass meadows Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:海草是唯一一类可以完全生活在海水中的高等被子植物,具有重要的生态服务功能和巨大的经济价值。但受气候变化和人类活动的双重影响,海草床退化趋势日益严峻。海草床生态系统受到外界胁迫后的稳定性和恢复能力很大程度上依赖于有性繁殖即种子繁殖,当胁迫造成海草死亡等不可逆转的伤害时,通过沉积物种子库能够进行种群维持和自我更新,因此研究海草种子扩散过程及种子库形成机制对海草生态系统稳定性的维持具有重要意义。综述了海草生活史类型、种子繁殖特征、种子扩散过程及影响因素、种子库形成机制等。在此基础上总结了目前研究存在的几方面不足和未来展望:1)不同环境胁迫条件对海草有性繁殖努力的影响研究;2)海草种子二次扩散的影响因素和扩散机制研究;3)沉积物沉降和再悬浮对种子扩散和截留的影响研究;4)环境因素变化下种子库的潜在分布和海草适宜生境预测与模拟。本研究以期为海草床生态系统的保护恢复研究提供理论参考。 Abstract:Seagrasses are the only higher angiosperms fully living in marine environments, which have important ecosystem service functions and enormous economic value. However, in recent years, the structure and function of seagrass ecosystems have been threatened by multiple global stressors caused by human activities and climate change, resulting in the continuous degradation of seagrasses. The stability and resilience of the seagrass ecosystem under external stress depend highly on its sexual reproduction, i.e., seed reproduction. When stressors cause irreversible damage to seagrasses, population maintenance and self-renewal could occur through sediment seed banks. Therefore, it is crucial to study the dispersal processes of seeds and the mechanism of seed bank formation, which play a key role in maintaining seagrass ecosystem stability. This paper reviews the life-history types, seed reproductive characteristics, seed dispersal processes and their influencing factors and seed bank formation of seagrass. On the basis of these understandings, we further proposed that future studies should focus on: 1) sexual reproductive efforts of seagrass under different environmental stress conditions; 2) the influencing factors and mechanism of secondary dispersal of seagrass seeds; 3) the influence of sediment deposition and resuspension on seed dispersal and retention processes; 4) prediction and simulation of the potential distribution of seagrasses and suitable habitat of seed bank under changing environments. This study is expected to provide theoretical references for the protection and restoration of seagrass meadow ecosystems. 参考文献 相似文献 引证文献

Modeling the potential distribution of the threatened Grey-necked Picathartes Picathartes oreas across its entire range

Summary Understanding the distribution and extent of suitable habitats is critical for the conservation of endangered and endemic taxa. Such knowledge is limited for many Central African species, including the rare and globally threatened Grey-necked Picathartes Picathartes oreas, one of only two species in the family Picathartidae endemic to the forests of Central Africa. Despite growing concerns about land-use change resulting in fragmentation and loss of forest cover in the region, neither the extent of suitable habitat nor the potential species’ distribution is well known. We combine 339 (new and historical) occurrence records of Grey-necked Picathartes with environmental variables to model the potential global distribution. We used a Maximum Entropy modelling approach that accounted for sampling bias. Our model suggests that Grey-necked Picathartes distribution is strongly associated with steeper slopes and high levels of forest cover, while bioclimatic, vegetation health, and habitat condition variables were all excluded from the final model. We predicted 17,327 km2 of suitable habitat for the species, of which only 2,490 km2 (14.4%) are within protected areas where conservation designations are strictly enforced. These findings show a smaller global distribution of predicted suitable habitat forthe Grey-necked Picathartes than previously thought. This work provides evidence to inform a revision of the International Union for Conservation of Nature (IUCN) Red List status, and may warrant upgrading the status of the species from “Near Threatened” to “Vulnerable”.

Geographical Distribution Variations of Humboldt Squid Habitat in the Eastern Pacific Ocean

The Humboldt squid Dosidicus gigas is a pelagic cephalopod species extensively distributed in the Eastern Pacific Ocean. Geographically separated habitat patterns of D. gigas show large spatiotemporal variations due to the distinct different regional environmental conditions. This study explored geographical variation in seasonal habitat of D. gigas off Peru and the Eastern Pacific Equator using maximum entropy (Maxent) model, with fishing occurrence data and environmental variables including sea surface temperature (SST), sea surface salinity, net primary production (NPP), photosynthetically active radiation (PAR), chlorophyll a concentration, eddy kinetic energy, and sea level anomaly. Results indicated that all the environmental variables exhibited conspicuous seasonal and geographical differences off Peru and the Eastern Pacific Equator. On the basis of the percent contribution from the Maxent model, seasonal and spatial extents of habitat were largely explained by SST, NPP, PAR, and eddy kinetic energy in the Eastern Pacific Equator and SST, sea surface salinity, NPP, and PAR off Peru. Suitable ranges of each environmental variable differed between regions and were controlled by the seasonal variability. Furthermore, movement patterns of longitudinal and latitudinal gravity centers of fishing effort of D. gigas were consistent with spatial and temporal distribution of suitable habitats but showed dramatically geographical variations off Peru and the Eastern Pacific Equator. Our findings highlighted Maxent mode’s ability in exploring Humboldt squid habitat hotspots in the Eastern Pacific Ocean and suggested that constructing the habitat model for D. gigas should consider the geographical differences under environmental conditions.

东方白鹳在山东省适宜栖息地的分布预测

PDF HTML阅读 XML下载 导出引用 引用提醒 东方白鹳在山东省适宜栖息地的分布预测 DOI: 10.5846/stxb202009052308 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 云南省基础研究计划项目(20210AT070040,2019FD0070) Prediction of the suitable habitat distribution of Oriental White Stork in Shandong Province Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:东方白鹳(Ciconia boyciana) 隶属鹳形目(Ciconiiformes)鹳科(Cioniidae)鹳属(Ciconia),被IUCN濒危物种红色名录列为濒危(EN),主要繁殖于俄罗斯远东地区与中国东北三江平原,在长江中下游鄱阳湖等沿海内陆湖泊越冬。山东省从2003年开始有东方白鹳繁殖记录,黄河三角洲为该物种在山东省的主要繁殖地。以在黄河三角洲自然保护区收集到的位点数据、物种分布数据库(GBIF)提取的位点数据和山东省环境气候因子为基础数据,基于最大熵(Maxent)模型和地理信息系统(ArcGIS)技术平台,预测东方白鹳在山东省的潜在适生区。结果表明在该物种在黄河三角洲及附近地区存在较集中的高适宜区,庙岛群岛和微山湖地区存在少量高适宜区,高适宜区总面积为1359.27km2;北至河北边界,南至微山县,沿黄河支流至西到达聊城市、菏泽市,存在1893.82km2较适宜区和3955.63km2低适宜区。潜在适宜生境总和为7208.72km2,占比为研究区域的0.89%。新出现的较为集中的较适宜区在微山湖周围地区,此地目前并无该物种出现的记录。通过对环境因子分析得知,东方白鹳选择适宜栖息地时更倾向于选择的植被类型是灌丛和草甸,土地利用类型是沼泽地、滩涂与河渠,远离道路,显著影响东方白鹳选择适宜区的气候因子是最暖季度降雨量和最干月份降雨量。研究旨在探究何种环境因子影响东方白鹳对适宜栖息地的选择,为该物种的栖息地管理和保护区建立提供科学依据,进而促进该物种种群和栖息地保护。 Abstract:The Oriental White Stork (Ciconia boyciana) belongs to the Ciconiiformes Stork family (Cioniidae) and the Stork genus (Ciconia). It is an endangered (EN) species on the International Union for Conservation of Nature (IUCN) Red List and is the national first-level protected wildlife. They mainly breed in the Far East of Russia and the Sanjiang Plain in Northeast China and overwinter in coastal inland lakes such as Poyang Lake in the middle and lower reaches of the Yangtze River. Shandong Province has recorded the reproduction of the Oriental White Stork since 2003. The Yellow River Delta is the main breeding ground for this species in Shandong Province. The purpose of this study is to explore what environmental factors affect the selection of suitable habitats for the Oriental White Stork. This article uses the site data collected in the Yellow River Delta Nature Reserve, the site data extracted from the Species Distribution Database (GBIF) and the environmental and climate factors of Shandong Province as the basic data, based on the Maximum Entropy (Maxent) model and geographic information system (ArcGIS), and predicts the potential suitable area of the Oriental White Stork in Shandong Province. The results show that the most suitable habitat for the species is concentrated in the Yellow River Delta and nearby areas. From the border of Hebei in the north of Shandong Province to Weishan County in the south, along the tributaries of the Yellow River to the west to Liaocheng City and Heze City, there are 3955.63 km2 low suitable areas and 1893.82 km2 more suitable area. The total potential suitable habitat is 7208.72 km2, of which the most suitable area is 1359.27 km2, accounting for 0.89% of the study area. The newly emerged more concentrated and more suitable patches are in the area around Weishan Lake, where there is currently no record of this species. Through the analysis of environmental factors, it is known that the vegetation types that the Oriental White Stork prefers to choose when choosing suitable habitats are shrubs and meadows, and the land use types are swamps, tidal flats and canals far away from roads. The climatic factors that significantly affect the Oriental White Stork's selection of suitable areas are the warmest quarter rainfall and the driest month rainfall. The results provide basic scientific evidence for the habitat management and establishment of the protected areas for this species, and promote the protection of the species' population and habitat. 参考文献 相似文献 引证文献

Will Greenland be the last refuge for the continental European small-white orchid?Niche modeling of future distribution of Pseudorchis albida

Climate change affects populations of plants, animals, and fungi not only by direct modifications of their climatic niches but also by altering their ecological interactions. In this study, the future distribution of suitable habitats for the small-white orchid (Pseudorchis albida) was predicted using ecological niche modeling. In addition, the effect of global warming on the spatial distribution and availability of the pollen vectors of this species was evaluated. Due to the inconsistency in the taxonomic concepts of Pseudorchis albida, the differences in the climatic preferences of three proposed subspecies were investigated. Due to the overlap of both morphological and ecological characters of ssp. albida and ssp. tricuspis, they are considered to be synonyms, and the final analyses were carried out using ssp. albida s.l. and ssp. straminea. All of the models predict that with global warming, the number of suitable niches for these orchids will increase. This significant increase in preferred habitats is expected to occur in Greenland, but habitat loss in continental Europe will be severe. Within continental Europe, Pseudorchis albida ssp. albida will lose 44%–98% of its suitable niches and P. albida ssp. straminea will lose 46%–91% of its currently available habitats. An opposite effect of global warming was predicted for pollinators of P. albida s.l., and almost all insects studied will be subject to habitat loss. Still, within the predicted potential geographical ranges of the orchid studied, some pollen vectors are expected to occur, and these can support the long-term survival of the small-white orchid.

Cordyceps cicadae and Cordyceps gunnii have closer species correlation with Cordyceps sinensis: from the perspective of metabonomic and MaxEnt models

Cordyceps sinensis is a second-class nationally-protected medicinal fungus and functional food. Cordyceps sinensis resources are endangered, and finding new medicinal materials is a fast and economical way to meet the current demonstrated demand, which can effectively solve the shortage of C. sinensis resources. In this study, the metabolite characteristics of Cordyceps were comprehensively revealed by LC-QTOF-MS technology. The maxent model can be used to predict the habitat suitability distribution of Cordyceps and screen out the main climatic factors affecting its distribution. The correlation model between climate factors and chemical components was established by Pearson correlation analysis. Finally, based on the analysis of climate factors and metabolites, we will analyze the high correlation species with C. sinensis, and develop them as possible alternative species of C. sinensis in the future. The results showed that the suitable area of Cordyceps cicadae demonstrated a downward trend, while that of C. sinensis, Cordyceps militaris and Cordyceps gunnii demonstrated an upwards trend. The suitable areas all shifted to the northwest. The temperature seasonality and max temperature of the warmest month are the maximum climatic factors affecting nucleosides. Compared with C. sinensis, the metabolic spectrum similarities of C. cicadae, C. militaris, and C. gunnii were 94.42%, 80.82%, and 91.00%, respectively. Cordyceps sinensis, C. cicadae, and C. gunnii were correlated well for compounds and climate factors. This study will explore whether C. cicadae, C. militaris and C. gunnii can be used as substitutes for C. sinensis. Our results may provide a reference for resource conservation and sustainable utilization of endangered C. sinensis.