scholarly journals Predicting habitat suitability of Selaginella adunca A.Br. ex Hieron., an endangered and endemic fern-allies of Western Himalaya

2020 ◽  
Vol 7 (3) ◽  
pp. 547-552
Author(s):  
Amber Srivastava ◽  
Keyword(s):  
Habitat Suitability ◽  
Rare Species ◽  
Ecological Niche ◽  
Habitat Type ◽  
Western Himalaya ◽  
Suitable Habitat ◽  
Anthropogenic Pressure ◽  
Niche Modelling ◽  
Maxent Model ◽  
Preferred Habitat

Selaginella adunca is a quite distinct and rare species of Selaginella found in Western Himalaya. This species is reported only from few populations occurring in India and Nepal. Since most of its reported habitats are under anthropogenic pressure, therefore for proper conservation of this species it is necessary to mark the suitable habitat for its conservation and reintroduction. The present study was aimed to find out the suitable habitat of this species through ecological niche modelling (ENM) technique using Maxent model. This will also help in relocating the species in other preferred habitat type and its reintroduction as well.

scholarly journals Little hope for the polyploid endemic Pyrenean Larkspur (Delphinium montanum): evidences from population genomics and Ecological Niche Modelling

2021 ◽  
Author(s):  
Pascaline Salvado ◽  
Pere Aymerich Boixader ◽  
Josep Parera ◽  
Albert Vila Bonfill ◽  
Maria Martin ◽  
...  
Keyword(s):  
Population Structure ◽  
Ecological Niche ◽  
Population Genomics ◽  
Diploid Species ◽  
Ecological Niche Modelling ◽  
High Mountain ◽  
Suitable Habitat ◽  
Sky Islands ◽  
Niche Modelling ◽  
Ecological Requirements

Species endemic to restricted geographical ranges represent a particular conservation issue, be it for their heritage interest. In a context of global change, this is particularly the case for plants which belong to high-mountain ecosystems and, because of their ecological requirements, are doomed to survive or disappear on their "sky islands". The Pyrenean Larkspur (Delphinium montanum, Ranunculaceae) is endemic to the Eastern part of the Pyrenees (France and Spain). It is now only observable at a dozen of localities and some populations show signs of decline, such as a recurrent lack of flowering. Implementing population genomic approach (e.g. RAD-seq like) is particularly useful to understand genomic patterns of diversity and differentiation in order to provide recommendations in term of conservation. However, it remains challenging for species such as D. montanum that are autotetraploid with a large genome size (1C-value > 10 pg) as most methods currently available were developed for diploid species. A Bayesian framework able to call genotypes with uncertainty allowed us to assess genetic diversity and population structure in this system. Our results show evidence for inbreeding (mean GIS = 0.361) within all the populations and substantial population structure (mean GST = 0.403) at the metapopulation level. In addition to a lack of connectivity between populations, spatial projections of Ecological Niche Modelling analyses under different climatic scenarios predict a dramatic decrease of suitable habitat for D. montanum in the future. Based on these results, we discuss the relevance and feasibility of different conservation measures.

Identification of key environmental variables associated with the presence of Toothed Leionema (Leionema bilobum serrulatum) in the Strzelecki Ranges, Victoria, Australia

2011 ◽  
Vol 59 (3) ◽  
pp. 207
Author(s):  
Wendy Wright ◽  
Xuan Zhu ◽  
Mateusz Okurowski
Keyword(s):  
Environmental Factors ◽  
Habitat Suitability ◽  
Rare Species ◽  
Environmental Variables ◽  
Geographical Information Systems ◽  
Predictive Modelling ◽  
Geographical Information ◽  
Suitable Habitat ◽  
Small Tree ◽  
Disturbed Areas

Toothed Leionema is one of four subspecies of Leionema bilobum from the Rutaceae family. A dense shrub or small tree, growing to ~4 m high, it is a poorly investigated species which is considered rare in Victoria, Australia. This paper presents the results of a study using Geographical Information Systems and Weights-of-Evidence predictive modelling to assess the importance of seven environmental factors in determining habitat suitability for this species in the Strzelecki Ranges, Victoria. This method is particularly useful in understanding the distribution of rare species, especially where the ecology of the species of interest is not well understood. Of the seven environmental factors considered here, four were found to be important: elevation, aspect, distance to water and distance to plantation (disturbed) areas. The modelling results indicate that areas with elevations between 350 and 550 m and a dominant south-western aspect that are close to plantation areas (within 700 m), and to water (within 1100–1200 m), provide potentially suitable habitat for Toothed Leionema in the region.

scholarly journals Maxent modelling for habitat suitability of vulnerable tree Dalbergia latifolia in Nepal

Silva Fennica ◽  
2021 ◽  
Vol 55 (4) ◽  
Author(s):  
Dipak Mahatara ◽  
Amul Acharya ◽  
Bishnu Dhakal ◽  
Dipesh Sharma ◽  
Sunita Ulak ◽  
...  
Keyword(s):  
Model Prediction ◽  
Habitat Suitability ◽  
Habitat Management ◽  
Natural Habitat ◽  
Area Under The Curve ◽  
Forest Conversion ◽  
Suitable Habitat ◽  
Timber Species ◽  
Jackknife Test ◽  
Maxent Model

Roxb., commonly known as rosewood, is one of the highly valuable tropical timber species of Nepal. The tree species was widely distributed in the past, however, over-exploitation of natural habitat, deforestation, forest conversion for agriculture, illegal logging and the invasion of alien species resulted in the classification of this species as vulnerable by the IUCN (International Union for Conservation of Nature) category. So, the prediction of habitat suitability and potential distribution of the species is required to develop restoration mechanisms and conservation interventions. In this study, we modelled the suitable habitat of over the entire possible range of Nepal using a Maxent model. We compiled 23 environmental variables (19 bioclimatic, 3 topographic and a vegetative layer), however, only 12 least correlated variables along with 43 spatially representative presence locations were retained for model prediction. We used a receiver operating characteristic (ROC) curve to assess the model’s performance and a Jackknife procedure to evaluate the relative importance of predictor variables. The model was statistically significant with an area under the curve (AUC) value of 0.969. The internal Jackknife test indicated that elevation was the most important variable for the model prediction with 71.3% contribution followed by mean temperature of driest quarter (9.8%). The most (>0.6) suitable habitat for the was 235 484 hectares with large sections of area in two provinces whereas, the western most provinces were not suitable for as per Maxent model. The information presented here can provide a framework for nature conservation planning, monitoring and habitat management of this rare and endangered species.Dalbergia latifoliaD. latifoliaD. latifoliaD. latifolia

scholarly journals Habitat Suitability Study of Hylomecon Japonica Based on Maxent Model in China

2020 ◽  
Author(s):  
Cao Zhen ◽  
Zhang Xiaoyan ◽  
Xue Xuanji ◽  
Zhang Lei ◽  
Zhan Guanqun ◽  
...  
Keyword(s):  
Habitat Suitability ◽  
Potential Distribution ◽  
Mean Annual Temperature ◽  
Suitable Habitat ◽  
Entropy Model ◽  
Factors Affecting ◽  
Jackknife Test ◽  
Maxent Model ◽  
Growth Area ◽  
The Mean

Abstract Background: To understand the potential distribution and habitat suitability of H. japonica in China. And to provide guidance for the wild cultivation and standardized planting of H. japonica. Methods: The maximum entropy model (Maxent) and geographic information system (ArcGIS) were applied to predict the potential suitable habitat of H. japonica species, and the contribution of variables were evaluated by using the jackknife test. Results: The AUC value confirmed the accuracy of the model prediction based on 101 occurrence records. The potential distributions of H. japonica were mainly concentrated in Jilin, Liaoning, Shaanxi and other provinces (adaptability index>0.6). Jackknife experiment showed that the precipitation of driest month (35.6%), precipitation of wettest quarter (13.4%), the mean annual temperature (7.8%) and the subclass of soil (7.8%) were the most important factors affecting the potential distribution of H. japonica. Conclusion: The niche parameters of the most suitable growth area (adaptability index>0.8) for H. japonica were precipitation of driest month (5 mm), precipitation of wettest quarter (400-490 mm), the mean annual temperature (-2-4 °C) and the subclass of soil (Glossy Chernozem, Gleyic Lime, Haplic Gypsisols).

scholarly journals Predicting habitat suitability for basking sharks (Cetorhinus maximus) in UK waters using ensemble ecological niche modelling

2019 ◽  
Vol 153 ◽  
pp. 101767 ◽  
Author(s):  
Rebecca A. Austin ◽  
Lucy A. Hawkes ◽  
Philip D. Doherty ◽  
Suzanne M. Henderson ◽  
Richard Inger ◽  
...  
Keyword(s):  
Habitat Suitability ◽  
Ecological Niche ◽  
Ecological Niche Modelling ◽  
Niche Modelling ◽  
Cetorhinus Maximus

scholarly journals Ecological assessment and environmental niche modelling of Himalayan rhubarb (Rheum webbianum Royle) in northwest Himalaya

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259345
Author(s):  
Ishfaq Ahmad Wani ◽  
Susheel Verma ◽  
Priyanka Kumari ◽  
Bipin Charles ◽  
Maha J. Hashim ◽  
...  
Keyword(s):  
Habitat Suitability ◽  
Ecological Niche ◽  
Climatic Conditions ◽  
Ecological Niche Modelling ◽  
Environmental Niche ◽  
Niche Modelling ◽  
Jammu And Kashmir ◽  
Actual Distribution ◽  
Potential Habitats ◽  
Rcp 8.5

In an era of anthropocene, threatened and endemic species with small population sizes and habitat specialists experience a greater global conservation concern in view of being at higher risk of extinction. Predicting and plotting appropriate potential habitats for such species is a rational method for monitoring and restoring their dwindling populations in expected territories. Ecological niche modelling (ENM) coalesces species existence sites with environmental raster layers to construct models that describe possible distributions of plant species. The present study is aimed to study the potential distribution and cultivation hotspots for reintroducing the high value, vulnerable medicinal herb (Rheum webbianum) in the Union territories of Jammu and Kashmir and Ladakh using population attributes and ecological niche modelling approach. Sixty-three populations inventoried from twenty-eight areas display a significant change in the phytosociological attributes on account of various anthropogenic threats. The current potential habitats coincide with actual distribution records and the mean value of Area Under Curve (AUC) was 0.98 and the line of predicted omission was almost adjacent to omission in training samples, thus validating a robustness of the model. The potential habitat suitability map based on the current climatic conditions predicted a total of 103760 km2 as suitable area for the growth of Rheum webbianum. Under the future climatic conditions, there is a significant reduction in the habitat suitability ranging from -78531.34 Km2 (RCP 4.5 for 2050) to -77325.81 (RCP 8.5 for 2070). Furthermore, there is a slight increase in the suitable habitats under future climatic conditions, ranging from +21.99 Km2 under RCP 8.5 (2050) to +3.14 Km2 under RCP 4.5 (2070). The Jackknife tests indicated Precipitation of Driest Month (BIO14) as the most contributing climatic variable in governing the distribution of R. webbianum. Therefore, scientifically sound management strategies are urgently needed to save whatever populations are left in-situ to protect this species from getting extinct. Present results can be used by conservationists for mitigating the biodiversity decline and exploring undocumented populations of R. webbianum on one hand and by policymakers in implementing the policy of conservation of species with specific habitat requirements by launching species recovery programmes in future on the other.

scholarly journals Response of Zooplankton Indices to Anthropogenic Pressure in the Catchment of Field Ponds

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 758 ◽  
Author(s):  
Natalia Kuczyńska-Kippen
Keyword(s):  
Rare Species ◽  
Plant Cover ◽  
Habitat Type ◽  
Open Water ◽  
Water Area ◽  
Ceratophyllum Demersum ◽  
Anthropogenic Pressure ◽  
Ecological Value ◽  
Small Water ◽  
Open Water Area

As methods for assessing the environmental conditions in ponds are still not well developed, I studied zooplankton to identify a response of community indices to abiotic, biotic, and habitat type in two types of ponds differing in the level of human stress. Ponds of low human alterations (LowHI) harbored generally richer communities and a higher share littoral zooplankton, whose occurrence was associated with higher water transparency and complex macrophyte habitat, particularly the presence of hornworts and charoids. In high human-impact ponds (HighHI) planktonic communities prevailed. Their distribution was mainly related to the open water area and fish presence. Anthropogenic disturbance was also reflected in the frequency of rare species, which were associated with LowHI ponds. Higher diversity of zooplankton increased the chance for rare species to occur. Despite the fact that the majority of rare species are littoral-associated, they had no prevalence towards a certain ecological type of plants, which suggests that any kind of plant cover, even macrophytes typical for eutrophic waters (e.g., Ceratophyllum demersum) will create a valuable habitat for conservation purposes. Thus, it is postulated that a complex and dense cover of submerged macrophytes ought to be maintained in order to improve the ecological value of small water bodies.

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