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Cremastraappendiculata (Orchidaceae) is a perennial medicinal herb, which is included in the national second-class protected plant catalog in China. Due to the influences of climate change and anthropogenic activities, in conjunction with soaring commercial prices, the wild sources of C.appendiculata have been drastically reduced and are in danger of extinction. Consequently, it is important to predict the distribution of potentially suitable growth/propagation areas for C.appendiculata under the backdrop of climate change for its protection and sustainable use. For this study, an optimized maximum entropy model was employed to analyze the distribution patterns and changes of potentially suitable regions for C.appendiculata during different periods since the Last Glacial Maximum (LGM, 18–24 ka). Based on multiple climate change scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5), the distribution range of C. appendiculata was predicted for the 2050s (average for 2041–2060), 2070s (average for 2061–2080), and 2090s (average for 2081–2100). The results revealed that during the LGM period, the highly suitable growth area for C.appendiculata was 0.28 × 104 km2, which accounted for only 3.26% of the current highly suitable growth area. During the mid-Holocene (MH, 6 ka) period, the area of highly suitable regions increased to 8.38 × 104 km2, which accounted for 99.30% of the present highly suitable growth area. Further, the cumulative existing potentially suitable growth area for C. appendiculata is 213.9 × 104 km2, which accounts for 22.28% of China's territory. Of these lands, the low, medium, and high suitable areas are 147.76 × 104 km2, 57.71 × 104 km2, and 8.44 × 104 km2, respectively. The highly suitable areas are primarily distributed across Sichuan, Gansu, Shaanxi, Chongqing, Guizhou, Hubei, and Anhui Provinces. Moreover, in the future the potentially suitable growth areas for C. appendiculata will decrease to varying degrees. Further, the results of this study found that the relatively low impact areas for C. appendiculata were mainly distributed across Shaanxi, Sichuan, Chongqing, and Guizhou Provinces. Centroid transfer analysis indicated that the center of potentially suitable growth areas for C.appendiculata shifted to the northwest in SSP2-4.5 and SSP3-7.0, while they initially shifted to the northwest and then to the southeast in SSP1-2.6 and SSP5-8.5. [ABSTRACT FROM AUTHOR]

Tomicus yunnanensis Kirkendall (Coleoptera: Scolytinae) is a stem-boring pest that endangers Pinus yunnanensis Franch (Pinales:Pinoideae), which seriously affects the ecological environment safety in southwest China. In order to understand the potential distribution pattern and change in the potential distribution of P. yunnanensis and T. yunnanensis, this study used the maximum entropy model to predict the distribution of potentially suitable areas for P. yunnanensis and T. yunnanensis and explored the relationships between their different spatiotemporal distributions based on change analysis. The experimental results show that altitude is the main factor restricting the current distribution of P. yunnanensis. The current suitable areas of P. yunnanensis are mainly distributed in Yunnan, Sichuan and Guizhou. The minimum temperature of the coldest month is the main factor affecting the current distribution of T. yunnanensis. The current suitable areas of T. yunnanensis are mainly distributed in Yunnan, Sichuan and Tibet. Under future climate scenarios, the total suitable areas of P. yunnanensis and T. yunnanensis are expected to increase. The suitable areas tend to move to higher altitudes in the west and higher latitudes in the north. At the same time, this study finds that there is an obvious bottleneck of expansion to northeastern Sichuan near the Daba Mountains. The results of intersection analysis showed that, with future climate change, P. yunnanensis and T. yunnanensis mainly showed lowly suitable (or unsuitable)—lowly suitable (or unsuitable) to moderately (or highly) suitable—and moderate (or high) variation patterns of suitable areas under the SSP1-2.6 climate scenario. These results will provide an important basis for the breeding of P. yunnanensis and controlling T. yunnanensis. [ABSTRACT FROM AUTHOR]

Simple Summary: Wild populations of C. pictus and C. amherstiae have been decreasing due to habitat fragmentation and long-term uncontrolled poaching. To support the Chrysolophus spp.'s conservation, we simulated the potential distribution of the two species in China, calculated the patch fragmentation index of suitable habitats of Chrysolophus spp. in nature reserve areas and non-nature reserve areas, and analyzed the habitat status of C. pictus and C. amherstiae in China. Compared with the previous studies, their habitat areas have been reduced. In addition, most of the suitable habitats were not in nature reserves and were highly fragmented. We offer recommendations for the Chinese government to formulate conservation schemes for the Chrysolophus spp. population in the future. Over the past few years, the wild population of Chrysolophus spp. has decreased remarkably. Habitat fragmentation is a significant cause for this serious threat to the survival of Chrysolophus spp. population. In order to further understand the distribution of potentially suitable habitats of Chrysolophus spp., we used the maximum entropy model to predict the potentially suitable habitats of C. pictus and C. amherstiae in China based on the known distribution. According to the prediction results of the model, we calculated the landscape pattern index to compare the fragmentation of the two species' potential suitable habitats in nature reserves and non-nature reserves. The results showed that the potentially suitable habitat for Chrysolophus spp. only accounted for a small area of China. The suitable habitats for C. pictus were mainly in Sichuan, Shaanxi, Hubei, and other provinces, and the model predicts a total area of 359,053.06 km2. In addition, the suitable habitats for C. amherstiae were mainly distributed in the three-parallel-river area, with a potential total area of 215,569.83 km2. The model also showed that there was an overlap of suitable habitats between the two species in the western edge of the Sichuan Basin. Previously, hybrids of the two pheasants have already been found in this same overlapping area predicted by the model. The landscape pattern index showed that in the potentially suitable habitat for Chrysolophus spp., the fragmentation of non-nature reserve areas was higher than that of nature reserve areas. The results revealed the distribution of potentially suitable habitats for Chrysolophus spp. in China and highlighted that the suitable habitats in non-nature reserve areas were in urgent need of conservation, thereby providing a key reference for the conservation of the Chrysolophus spp. population in the future. [ABSTRACT FROM AUTHOR]

This study evaluated the potential distribution of the potato tuber moth. This species severely impacts global potato production, especially in China and India, which have the world's largest potato production. We developed two indices considering host plant availability and production in addition to climatic suitability, which was simulated using the CLIMEX model. Thus, three different indices were used to project potential distribution of the potato tuber moth under a climate change scenario: (1) climatic suitability (ecoclimatic index (EI)) (EIM), (2) climatic suitability combined with host plant availability (EIN1), and (3) climatic suitability combined with host plant production (EIN2). Under the current climate, EIM was high in southern India and central to southern China, while EIN1 and EIN2 were approximately 38% and 20% lower than EIM, respectively. Under the Special Report on Emissions Scenario A1B, the potato tuber moth would probably not occur in India, but its distribution could be extended to the north, reaching N47°. The areas with the highest climatic suitability by potato tuber moth based on three indices were Sichuan and Karnataka in response to climate change. These areas require adequate pest control, such as prevention of spread through transport of potato seed or by using cold storage facilities. [ABSTRACT FROM AUTHOR]