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北部湾印太江豚密度估算及适宜栖息地预测 被引量:2
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作者 孟祥垚 汪华志 +3 位作者 周煜 张宏科 乔莹 陈炳耀 《兽类学报》 CAS CSCD 北大核心 2022年第4期362-369,共8页
目前我国印太江豚(Neophocaena phocaenoides)的基础信息十分有限,2018-2020年对北部湾离岸较近的广西壮族自治区合浦儒艮国家级自然保护区及离岸较远的涠洲岛水域进行了截线抽样法船只考察。应用DISTANCE估算出儒艮国家级自然保护区印... 目前我国印太江豚(Neophocaena phocaenoides)的基础信息十分有限,2018-2020年对北部湾离岸较近的广西壮族自治区合浦儒艮国家级自然保护区及离岸较远的涠洲岛水域进行了截线抽样法船只考察。应用DISTANCE估算出儒艮国家级自然保护区印太江豚密度约为每平方千米0.273(0.133~0.561)头,数量约88头(95%CI:43~181);涠洲岛水域印太江豚密度约为每平方千米0.100(0.048~0.210)头,数量约137头(95%CI:65~286)。利用最大熵模型(MaxEnt)分析北部湾水域印太江豚的适宜栖息地分布及面积。MaxEnt模型训练集和测试集AUC值分别为0.980和0.927,模型拟合度较好,结果表明离岸距离和海洋深度是影响印太江豚栖息地分布的主要因子,印太江豚的适宜栖息地在北部湾东北部近岸区和海南西侧,适宜度超过0.5的栖息地面积达14630.62 km^(2)。2018-2020年印太江豚适宜栖息地面积较2013年大幅度下降,0.5适宜度的栖息地面积减少了40%。参考印太江豚2个群体的平均密度和北部湾适宜栖息地面积,粗略估计北部湾水域印太江豚约1463~3994头。由此可见,北部湾水域内印太江豚密度比较高,应引起足够的重视。建议首先进行区域性海洋环境的整体保护,重点关注鱼类资源的恢复及对人类活动尤其渔船的管控,并尽快建立新的自然保护区。 展开更多
关键词 北部湾 栖息地分析 儒艮国家级自然保护区 涠洲岛 印太江豚
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秩和检验在鸟类栖息地选择分析中的运用 被引量:4
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作者 杨维康 乔建芳 +1 位作者 高行宜 钟文勤 《干旱区研究》 CSCD 2001年第3期42-44,共3页
目前 ,t检验 (t -test)在鸟类栖息地选择分析中被广泛运用于两个独立样本平均数的比较 ,但它对数据的分布形式要求较严格。本文介绍了一种非参数检验方法 -秩和检验 (Mann -WhitneyU -tests) ,并通过实例分析比较了t检验与秩和检验。结... 目前 ,t检验 (t -test)在鸟类栖息地选择分析中被广泛运用于两个独立样本平均数的比较 ,但它对数据的分布形式要求较严格。本文介绍了一种非参数检验方法 -秩和检验 (Mann -WhitneyU -tests) ,并通过实例分析比较了t检验与秩和检验。结果表明 ,在样本数据量较大时 ,秩和检验与t检验具有同等的检验精确性。与t检验相比 ,秩和检验操作更为简便。 展开更多
关键词 T检验 秩和检验 鸟类 栖息地选择分析 非参数检验
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The possibility analysis of habitats,origin and reappearance of bloom green alga(Enteromorpha prolifera) on inshore of western Yellow Sea 被引量:12
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作者 丁兰平 费修绠 +2 位作者 陆勤勤 邓蕴彦 连绍兴 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期421-424,共4页
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible w... Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide. 展开更多
关键词 bloom green alga Enteromorpha prolifera ORIGIN HABITATS reappearance western Yellow Sea
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A Remote Sensing-based Analysis on the Impact of Wenchuan Earthquake on the Core Value of World Nature Heritage Sichuan Giant Panda Sanctuary 被引量:8
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作者 YU Hu ZHAO Yongtao +4 位作者 MA Yuewei SUN Yulian ZHANG Hu YANG Shihong LUO Yong 《Journal of Mountain Science》 SCIE CSCD 2011年第3期458-465,共8页
In this study,we used remotely sensed data,GIS modeling,and statistical methods to evaluate the damage caused by the Wenchuan Earthquake (May 12,2008) to the giant panda (Ailuropoda melanoleuca) habitat in the World N... In this study,we used remotely sensed data,GIS modeling,and statistical methods to evaluate the damage caused by the Wenchuan Earthquake (May 12,2008) to the giant panda (Ailuropoda melanoleuca) habitat in the World Nature Heritage Sichuan Giant Panda Sanctuary (WHSGPS) in China.A landscape ecological analysis found increases of landscape heterogeneity,complexity,and fragmentation in the giant panda habitat after the earthquake.A terrain analysis found that slope and elevation are directly associated with the distribution of the damaged areas.As slope and elevation increase,the size of the damaged area keeps increase until to a peak,and then starts to drop.The total area of the damaged vegetation in our study area is 114.26 km 2,accounting for 3.78% of the study area;30.46% of that 114.26 km 2 is located in the Core Zone of WHSGPS.There are 18.57km 2 of the damaged vegetation located in the identified suitable giant panda habitat,accounting for 1.75% of the total area of suitable giant panda habitats in the study area.Based on these findings,we conclude that the Wenchuan Earthquake does not have significant impact on the WHSGPS as a whole. 展开更多
关键词 World Nature Heritage Giant Panda Sanetuaries Suitable giant panda habitat Model Wenehuan Earthquake Landscape pattern GIS RS
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Reconsidering the efficiency of grazing exclusion using fences on the Tibetan Plateau 被引量:30
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作者 Jian Sun Miao Liu +23 位作者 Bojie Fu David Kemp Wenwu Zhao Guohua Liu Guodong Han Andreas Wilkes Xuyang Lug Youchao Chen Genwei Cheng Tiancai Zhou Ge Hou Tianyu Zhan Fei Peng Hua Shang Ming Xu Peili Shi Yongtao He Meng Li Jinniu Wang Atsushi Tsunekawa Huakun Zhou Yu Liu Yurui Li Shiliang Liu 《Science Bulletin》 SCIE EI CAS CSCD 2020年第16期1405-1414,M0004,共11页
Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau(TP)and elsewhere.However,there is a limited understanding of the effect... Grazing exclusion using fences is a key policy being applied by the Chinese government to rehabilitate degraded grasslands on the Tibetan Plateau(TP)and elsewhere.However,there is a limited understanding of the effects of grazing exclusion on alpine ecosystem functions and services and its impacts on herders’livelihoods.Our meta-analyses and questionnaire-based surveys revealed that grazing exclusion with fences was effective in promoting aboveground vegetation growth for up to four years in degraded alpine meadows and for up to eight years in the alpine steppes of the TP.Longer-term fencing did not bring any ecological and economic benefits.We also found that fencing hindered wildlife movement,increased grazing pressure in unfenced areas,lowered the satisfaction of herders,and rendered substantial financial costs to both regional and national governments.We recommend that traditional free grazing should be encouraged if applicable,short-term fencing(for 4-8 years)should be adopted in severely degraded grasslands,and fencing should be avoided in key wildlife habitat areas,especially the protected large mammal species. 展开更多
关键词 Grazing exclusion WILDLIFE GRAZING Grassland management DROUGHT Tibetan Plateau
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Multi-scale analysis to uncover habitat use of red-crowned cranes: Implications for conservation 被引量:12
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作者 Chunyue LIU Hongxing JIANG +3 位作者 Shuqing ZHANG Chunrong LI Yunqiu HOU Fawen QIAN 《Current Zoology》 SCIE CAS CSCD 2013年第5期604-617,共14页
A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lackin... A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lacking. We evaluated the effects of several habitat variables quantified across many spatial scales on crane use and abundance in two periods (2000 and 2009) at Yancheng National Nature Reserve, China. The natural wetlands decreased in area by 30,601 ha (-6.9%) from 2000 to 2009, pre- dominantly as a result of conversion to aquaculture ponds and farmland, and the remaining was under degradation due to expan- sion of the exotic smooth cordgrass. The cranes are focusing in on either larger patches or those that are in close proximity to each other in both years, but occupied patches had smaller size, less proximity and more regular boundaries in 2009. At landscape scales, the area percentage of common seepweed, reed ponds and paddy fields had a greater positive impact on crane presence than the area percentage of aquaculture ponds. The cranes were more abundant in patches that had a greater percent area of common seepweed and reed ponds, while the percent area of paddy fields was inversely related to crane abundance in 2009 due to changing agricultural practices. In 2009, cranes tended to use less fragmented plots in natural wetlands and more fragmented plots in anthropogenic paddy fields, which were largely associated with the huge loss and degradation of natural habitats between the two years. Management should focus on restoration of large patches of natural wetlands, and formation of a relatively stable area of large paddy field and reed pond to mitigate the loss of natural wetlands [Current Zoology 59 (5): 604-617, 2013]. 展开更多
关键词 Red-crowned crane Habitat Selection Remote sensing Scale PATCH LANDSCAPE
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