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1.
Proc Natl Acad Sci U S A ; 121(20): e2320674121, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38684007

RESUMEN

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.


Asunto(s)
Anfibios , Biodiversidad , Filogenia , Animales , Anfibios/clasificación , China , Conservación de los Recursos Naturales
3.
Zool Res ; 41(6): 670-683, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-32918407

RESUMEN

The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables. Disjunct alpine communities are geographically isolated from one another but experience similar environmental impacts. Isolated homogenous habitats may promote speciation but constrain functional trait variation. In this study, we examined the hypothesis that dispersal limitation promotes taxonomic divergence, whereas habitat similarity in alpine mountains leads to functional convergence. We performed standardized field investigation to sample non-volant small mammals from 18 prominent alpine sites in the Three Parallel Rivers area. We estimated indices quantifying taxonomic and functional alpha- and beta-diversity, as well as beta-diversity components. We then assessed the respective importance of geographical and environmental predictors in explaining taxonomic and functional compositions. No evidence was found to show that species were more functionally similar than expected in local assemblages. However, the taxonomic turnover components were higher than functional ones (0.471±0.230 vs. 0.243±0.215), with nestedness components showing the opposite pattern (0.063±0.054 vs. 0.269±0.225). This indicated that differences in taxonomic compositions between sites occurred from replacement of functionally similar species. Geographical barriers were the key factor influencing both taxonomic total dissimilarity and turnover components, whereas functional beta-diversity was primarily explained by climatic factors such as minimum temperature of the coldest month. Our findings provide empirical evidence that taxonomic and functional diversity patterns can be independently driven by different ecological processes. Our results point to the importance of clarifying different components of beta-diversity to understand the underlying mechanisms of community assembly. These results also shed light on the assembly rules and ecological processes of terrestrial mammal communities in extreme environments.


Asunto(s)
Genoma Mitocondrial , Presbytini/genética , Distribución Animal , Animales , Asia , ADN/genética , Heces/química , Femenino , Masculino , Filogenia , Especificidad de la Especie
4.
Zookeys ; 864: 147-160, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31367180

RESUMEN

The flying squirrels of the tribe Pteromyini (Family Sciuridae) currently include 15 genera of which the genus Biswamoyopterus comprises two recognized species, B.biswasi Saha, 1981 and B.laoensis Sanamxay et al., 2013. These two species were each described from only one specimen that are separated from each other by 1,250 kilometres in southern Asia, where they occur in northeast India and central Lao PDR respectively. In 2017 and 2018, two specimens of Biswamoyopterus were discovered from Mount Gaoligong, west Yunnan province, southwest China (between the type locality of the two recognized species). This study aimed to evaluate the taxonomic status of these two newly acquired specimens of Biswamoyopterus by comparing their morphology with the two described species of the genus. The results of this study showed that the specimens from Yunnan province (China) differed from both B.laoensis and B.biswasi in both pelage colour and craniology, and should be recognised as a distinct species, B.gaoligongensis sp. nov., which is formally described here. This study contributes to the understanding of the flying squirrels of southern Asia and identifies an additional species that appears to be endemic to southwest China; however, more research is required to provide details of its ecology, distribution, and conservation status.

5.
Zool Res ; 39(6): 406-412, 2018 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-29872032

RESUMEN

Understanding the spatial patterns of human-wildlife conflict is essential to inform management decisions to encourage coexistence, but it is constrained by the lack of spatially-explicit data. We collected spatially-implicit data of human-wildlife conflicts from 2009-2015 around Daxueshan Nature Reserve, Yunnan, China, and investigated the patterns and drivers of these conflicts. A questionnaire was also designed to capture local resident attitudes toward insurance-based compensation for the losses caused by targeted wildlife. We found that the Asiatic black bear (Ursus thibetanus) was the most conflict-prone animal around the reserve, followed by the rhesus macaque (Macaca mulatta) and Southeast Asian sambar (Cervus equinus). Conflicts were unevenly distributed among seasons, villages, and communities, with several grids identified as conflict hotspots. Poisson models revealed that human-bear conflicts were negatively related to distance to the reserve and proportion of forest, but positively correlated to the proportion of cropland. Binomial models showed that communities affected by crop depredation were positively correlated with the proportion of cropland and negatively correlated with distance to the reserve, whereas communities affected by livestock depredation were negatively correlated with the proportion of cropland. The insurance-based scheme has compensated over 90% of losses, to the satisfaction of 90.6% of respondents. Our results suggest that human-bear conflict could be potentially reduced by eliminating food crops near the reserve boundary and livestock grazing at conflict hotspots. In addition, the insurance-based scheme could be replicated at a broader scale with improvement in loss assessment.


Asunto(s)
Animales Salvajes , Conservación de los Recursos Naturales , Animales , China , Compensación y Reparación , Conflicto Psicológico , Productos Agrícolas , Ciervos , Humanos , Macaca mulatta , Ursidae
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(2): 498-504, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24822428

RESUMEN

Fast Fourier transforms (FFT) is a basic approach to remote sensing image processing. With the improvement of capacity of remote sensing image capture with the features of hyperspectrum, high spatial resolution and high temporal resolution, how to use FFT technology to efficiently process huge remote sensing image becomes the critical step and research hot spot of current image processing technology. FFT algorithm, one of the basic algorithms of image processing, can be used for stripe noise removal, image compression, image registration, etc. in processing remote sensing image. CUFFT function library is the FFT algorithm library based on CPU and FFTW. FFTW is a FFT algorithm developed based on CPU in PC platform, and is currently the fastest CPU based FFT algorithm function library. However there is a common problem that once the available memory or memory is less than the capacity of image, there will be out of memory or memory overflow when using the above two methods to realize image FFT arithmetic. To address this problem, a CPU and partitioning technology based Huge Remote Fast Fourier Transform (HRFFT) algorithm is proposed in this paper. By improving the FFT algorithm in CUFFT function library, the problem of out of memory and memory overflow is solved. Moreover, this method is proved rational by experiment combined with the CCD image of HJ-1A satellite. When applied to practical image processing, it improves effect of the image processing, speeds up the processing, which saves the time of computation and achieves sound result.

7.
Zoo Biol ; 30(3): 296-307, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20853413

RESUMEN

The food habits of Rhinopithecus bieti were studied at Mt. Longma in Tianchi Nature Reserve, Yunnan Province, China using microhistological analysis of feces and phytochemical component analysis of food items, from January 2007 to March 2008. This region is the southernmost location of R. bieti with the most complex and varied vegetation types. R. bieti fed on 83 plant species of 26 families, at least 3 species of lichens and bamboos, respectively. The number of food items exploited varied markedly among seasons, with dietary diversity being greatest in summer and autumn. Young leaves of broadleaf plant, monocotyledonous plant leaves (bamboos), and 3 species of lichens in the genera Bryoria (Bryoria confuse) and Usnea (Unsea longissima and Unsea florida) were frequently eaten. Bamboos (Poaceae) and lichens formed a stable dietary constituent throughout the year, contributing about 24 and 13%, respectively, of the total feeding records. There was seasonal variation in the proportion of each food type in the diet of the R. bieti. Results of the phytochemistry analysis showed that food selectivity of R. bieti was positively correlated with the ratio of crude protein to neutral detergent fibre (CP/NDF) and negatively correlated with condensed tannins (CT). Results from the study also showed that the primary food items eaten by R. bieti in summer had higher CP and lower CT than in winter.


Asunto(s)
Colobinae/fisiología , Heces/química , Conducta Alimentaria/fisiología , Animales , China , Ecosistema , Líquenes/clasificación , Plantas/clasificación
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