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A revised species population estimate for the Bar-headed Goose(Anser indicus) 被引量:4
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作者 Dongping Liu Guogang Zhang +3 位作者 Fengshan Li Tian Ma Jun Lu Fawen Qian 《Chinese Birds》 CSCD 2017年第1期57-62,共6页
Background: The Bar-headed Goose(Anser indicus) is a species that relies heavily on the plateau wetlands of Asia and whose population was thought to be declining. Over the past decade, south-central Tibet, one of the ... Background: The Bar-headed Goose(Anser indicus) is a species that relies heavily on the plateau wetlands of Asia and whose population was thought to be declining. Over the past decade, south-central Tibet, one of the most important wintering grounds, supported large numbers of Bar-headed Geese, but the population had not been regularly monitored in this area.Methods: We surveyed wintering Bar-headed Geese along the Yarlung Zangbo, Lhasa and Nyang Qu rivers, the three major river valleys and their tributaries in south-central Tibet in January 2014 and recorded their location, flock size and habitat utilization. Based on these data and the latest wintering counts elsewhere, we revised the population estimate for this species.Results: We recorded more than 67,000 Bar-headed Geese in south-central Tibet during January 2014. By geographic area, the geese were most abundant in the Lhasa River valley(38.5%) and the Nyang Qu River valley(31.0%), and by administrative division in Lhunzhub(27.2%) and Shigatse(26.7%). Bar-headed Geese were most often observed feeding in winter wheat fields and ploughed fields, resting on pastureland and marshes. The approximate number of 67,000 geese recorded in Tibet is more than four times the estimate of 1993 for the same region and exceeds the most recent world population estimate of 52,000–60,000. Based on our work in Tibet and the latest wintering counts available from other areas, we revised the estimated population size of this species to 97,000–118,000.Conclusions: Our result reveals a remarkable increase in the number of Bar-headed Geese wintering in south-central Tibet. This population increase most likely stems from a proliferation of cropland and especially winter wheat fields in south-central Tibet. This habitat improvement may also cause short-stopping of the Bar-headed Goose and thus reduce mortality of the geese that would otherwise undertake a somewhat daunting trans-Himalayan migration. 展开更多
关键词 Bar-headed Goose species population estimate TIBET Wintering ground
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Research Progress on Manglietia ventii,A Wild Plant Species with Extremely Small Populations
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作者 Bin WANG Xinglin AN +3 位作者 Zherong WU Hongmei ZHAO Xiangxin YU Xingmei AI 《Asian Agricultural Research》 2023年第3期40-46,共7页
Manglietia ventii is a wild plant species with extremely small populations endemic to Yunnan,mainly distributed in southeast Yunnan.Due to the continuous deterioration of natural habitats,excessive felling and utiliza... Manglietia ventii is a wild plant species with extremely small populations endemic to Yunnan,mainly distributed in southeast Yunnan.Due to the continuous deterioration of natural habitats,excessive felling and utilization of human beings,and the decline of breeding ability,the number of individuals in the population has decreased significantly.Through field investigation and literature review,the research status of M.ventii in systematics,conservation ecology,reproductive biology,genetic diversity,endangered mechanism and resource protection at home and abroad are systematically reviewed.And the future research direction is prospected.It is necessary to strengthen the research on the basic characteristics of M.ventii,explore the transmission route of M.ventii and deepen the development and utilization of resources,in order to provide a theoretical support for the protection and sustainable utilization of germplasm resources of M.ventii,and provide a reference for the protection of other wild plant species with extremely small populations. 展开更多
关键词 Manglietia ventii Plant species with extremely small populations(PSESP) Research progress
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Study on Resource Status and Protection Countermeasures of Wild Plant Species with Extremely Small Populations(PSESP)in Xinjiang
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作者 Li CHEN Ting NIU Xin HAN 《Meteorological and Environmental Research》 CAS 2022年第2期83-97,I0002-I0010,共24页
In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjian... In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjiang,including 22 species of trees,18 species of shrubs and 35 species of herbs.The habitats are mainly in extremely cold,extremely dry or extremely narrow conditions such as snow line,desert,mountain,wetland and so on.②53 species(70.67%)are listed as national or autonomous region protected plants,and 22 species of PSESP are not listed in the protection;there are 70 species of PSESP listed in the red list,accounting for 93.33%.③The PSESP in Xinjiang are mainly distributed in the Altai Mountains,western Tianshan Mountains,Pamir Plateau and Karakoram Mountains;they are distributed in all kinds of nature reserves,forest parks,wetland parks and other natural ecological protection areas in Xinjiang.Ammopiptanthus nanus(M.Pop.)Cheng F.,Cistanche tubulosa(Schenk)Wight,Calligonum roborovskii A.Los.and Prunus cerasifera Ehrhart have not been found in the literature,indicating that they are distributed in protected areas.In order to provide a theoretical basis for the conservation of biodiversity in Xinjiang,this paper puts forward some suggestions on the protection of PSESP. 展开更多
关键词 Wild plant species with extremely small populations(PSESP) Resource status Protection countermeasures XINJIANG
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Seasonal waterbird population changes in Lashihai Lake in northwest Yunnan, China 被引量:3
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作者 LIAO Jun-tao YE Hui +1 位作者 HUANG Ting-fa PENG Gui-hong 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1852-1862,共11页
We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the wat... We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the waterbird population. The study was conducted at five selected spots along Lashihai Lake at the same time each week from August 2011 to September 2013. In total, 62 waterbird species were recorded, of which 38.71%, 35.48%, 16.13%, and 9.68% were winter migrants, passage visitors, residents, and summer migrants, respectively. We found important seasonal changes in waterbird species composition and population size. Waterbird species richness was highest from September to the following April, with the total species numbers peaking in December. Total individual numbers peaked twice from late November to early December and mid-to-late February. However, waterbird species and individual numbers were comparatively lower from May to August. The change in species composition was determined by the arrival and departure dynamics of winter migrants and passage visitors. Winter migrants primarily caused the periodic changes in population size. Of concern,species and overall waterbird numbers seemed to be lower than the numbers in historical records. The decline of waterbird numbers implies that environmental changes caused by the implementation of the dam upstream of Lashihai Lake may have had adverse effects on this waterbird population. This study confirms the existence of major seasonal changes in species composition and size of the waterbird population at Lashihai Lake. Furthermore, the findings demonstrate that this wetland is of high conservation importance for waterbirds using the Central Asian–Indian and Asian–Pacific migratory routes. 展开更多
关键词 Seasonal variation species number Individual number Waterbird population
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Informative ISSR Markers Help Identify Genetically Distinct Accessions of Oryza rufipogon in Yield Improvement 被引量:3
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作者 G.HARITHA T.SUDHAKAR +3 位作者 D.CHANDRA T.RAM B.DIVYA N.SARLA 《Rice science》 SCIE CSCD 2016年第5期225-241,共17页
Inter simple sequence repeat(ISSR) polymorphism was used to determine genetic diversity and phylogenetic relationships in 90 genotypes of wild and cultivated species of Oryza from different geographical regions of t... Inter simple sequence repeat(ISSR) polymorphism was used to determine genetic diversity and phylogenetic relationships in 90 genotypes of wild and cultivated species of Oryza from different geographical regions of the world. In all the 17 primers used in ISSR-PCR, a total of 11 464 bands were amplified at 253 band positions/loci. The primer UBC-809 amplified the maximum bands(1 059) at 21 band positions. UBC-810 and UBC-835 amplified the minimum of 391 bands each at 7 and 14 band positions, respectively. The mean polymorphism information content ranged from 0.44 to 0.84 and resolving power ranged from 8.69 to 23.53. Un-weighted pair group method with arithmetic mean dendrogram and population structure based on the 17 primers separated all genotypes into 4 major clusters with a genetic similarity of 53%–100%. The first two clusters consisted of 30 O. rufipogon accessions each. In the third cluster, O. nivara and O. longistaminata grouped as one sub-cluster and all other O. nivara accessions and cultivars grouped as another sub-cluster. The fourth cluster had only five O. rufipogon accessions which can be a source of new genes. Four sub-populations were identified within O. rufipogon and two sub-populations within O. nivara at K = 7. A subset of six primers with high resolving power values were the most informative and grouped all genotypes almost similarly as the 17 primers did. Use of these six highly informative primers in ISSR-PCR is a cost effective and robust method for assessing genetic diversity in large germplasm collections of wild rice species. 展开更多
关键词 Oryza wild species genetic diversity population structure inter simple sequence repeat
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