4 Discussion
In plant species the Satyrium species are endangered and rare which is the important resources (21). MaxEnt model were applied to records the distribution and predict the potential distribution areas ofS. ciliatum , S. nepalense , and S. yannanense. The values for training data by AUC were 0.988, 0.981 and 0.958, and it shows that MaxEnt predictions is valid. According to the four different future scenarios, that the suitable habitat area for Satyrium’sin China will extend in 2050s and 2070s, and the suitable habitat area will move slowly to the higher altitude area in Northwest side of China, where the humidity and habitat is suitable for the growth ofSatyrium species. The prediction shows the in upcoming future will be the most suitable for the growth for Satyrium species. Its shows that generally the suitable habitat is stable and cause of the climatic change the species will face no extinctions. The study will show the new areas for the species distribution. The findings were in good agreement with the findings of the studies published peviosuly, thus indicating that, in some regions, habitat suitability of plant species improves under climate change conditions (22, 23). The area of species covering 20% of the earth’s surface will face the risk of extinction (24). About 15%–37% of the species will be endangered, as predicted by the distribution of the species under the future climate scenario. One of the reasons for the endangered status ofSatyrium is that most Satyrium species are hermaphroditic. Some species rely on birds and other animals for long-distance transmission. The species population is small, and the quality of seed development is low because of long-distance pollination (25). This study’s results provide a reliable basis for the protection ofSatyrium . People should effectively protect its native habitat and population. Nature reserves of Satyrium should be set up now according to the prediction results, and they should be strengthened to minimize human-made damage.
The results of the current study, using the response curve, obtained the thresholds (existence probability > 0.5) for the main bioclimatic parameters. Regarding S. ciliatum , isothermality (Bio3) ranged from 44 to 51.5, temperature seasonality (Bio4) ranged from 420 to 580, and mean temperature of the coldest quarter (Bio11) ranged from 1 to 13. Temperature seasonality (Bio4) ranged from 400-580, Isothemality (Bio3) ranged from 44-53 and precipitation of the coldest quarter (Bio19) ranged from 25-80mm for S.nepalense. Temperature seasonality (Bio4) ranged from 300-600mm, Isothermility (Bio3) ranged from 41-53 and lower temperature of coldest month(Bio06) from -6-6°C forS. yunnanense. This shows that the main environmental factors affecting the suitable distribution of Satyrium are temperature and precipitation. The plant distribution patterns can be detected by the environmental factors like temperature and precipitation (26, 27). Geographical distribution of species can be determined by the climate change and geographical distribution of species also response to change in climate (28). The structures of terrestrial ecosystems have been changed by global warming, and the habitat and geographical distribution functions of species have been changed by the structure of terrestrial ecosystems in turn (29). For instance, climate, topography, soil, human disturbance and spatial constraints are significant to the distribution of many different spatial scales(30). More studies have shown that the dominant variables restricting geographical distribution of plants are energy supply needed to complete life cycles, plenty of water, and cold tolerance (31). Based on the prediction of the MaxEnt model, the area of the current potential suitable habitat of Satyrium mainly located in Southwest China, which has a typical subtropical monsoon climate (32). Previous studies have indicated that precipitation is the main varaible affecting plants growth, regeneration, nutrient cycles, and community productivity in different habitats (33, 34). The environmental data used in the study just included the bioclimatic variables in WorldClim. We did not study soil type, land use, human activities, biological interaction, and other factors that influence the distribution of Satyrium . Certainly, the more factors that are included, the more accurate the prediction will be. Therefore, other factors affecting the potential suitable habitat of Satyriumshould be studied in the future, with different niche prediction models predicting the areas of the potential suitable habitats. This will make the prediction of results more reliable.