FOREST LANDSCAPE AND BIRD DIVERSITY IN MOUNTAIN REGION, XISHUANGBANNA, YUNNAN     

王直军 《中国地理科学(英文版)》1999,(2)

１ＧＥＮＥＲＡＬＳＩＴＵＡＴＩＯＮＯＦＴＨＥＳＴＵＤＩＥＤＡＲＥＡ１．１ＮａｔｕｒａｌＥｎｖｉｒｏｎｍｅｎｔＴｈｅｓｔｕｄｙｗａｓｃｏｎｄｕｃｔｅｄｉｎｔｈｅＪｉｎｕｏＭｏｕｎｔａｉｎ（２０°５３′１１″－２２°９′５９″Ｎ,１００°５５′３３″－１...  相似文献   

四合屯含鸟化石层地球化学异常及沉积环境   总被引：2，自引：0，他引：2  

丁秋红  金成洙  张立东  郭胜哲  张长捷  彭艳东  贾斌  陈树旺  邢德和  郑月娟 《地质与资源》2003,12(3):139-145

分析了四合屯含鸟化石沉积层的古生物组合、沉积环境及地球化学异常特征.研究表明,沉积物广泛发育水平层理,以泥岩等细碎屑为主,普遍含有火山碎屑物;剖面上的化石层可以划分3个化石组合,鸟化石产于中部组合;由于火山作用的影响,至少存在3次火山地震活动;湖面发生过3次规模较大的升降变化,火山活动造成了生物灾难性死亡;稀土元素δCe异常和多种微量元素异常揭示了古盆地环境的变化及其对生物界的影响.  相似文献   

东台条子泥候鸟栖息地与毗邻潮间带表层沉积物重金属含量及其生态风险评价          下载免费PDF全文

蔡桢杰  李果  旷泽行  王寿兵 《应用海洋学学报》2023,42(4):656-665

为了解世界自然遗产地生态修复的“中国样本”和“鸟类保护的国际地标” ——江苏东台条子泥“720”高潮位候鸟栖息地的生态环境质量,本研究采用电感耦合等离子体发射光谱法和原子荧光光谱法测定了高潮位候鸟栖息地5个样点及与之毗邻的堤外潮间带4个样点表层沉积物中8种常见重金属元素（Hg、Cd、Cr、As、Pb、Cu、Ni和Zn）的含量,基于地累积指数法和潜在生态风险指数法对两个区域表层沉积物中重金属含量特征和生态风险进行了比较研究。结果表明,候鸟栖息地和堤外潮间带表层沉积物中8种重金属的平均含量均未超过国家海洋沉积物质量一类标准,两个区域表层沉积物的重金属含量具有显著的差异（P<0.05）,候鸟栖息地沉积物各重金属平均含量均高于堤外区,两个区域潜在生态风险指数也具有显著差异,候鸟栖息地沉积物重金属潜在生态风险大于堤外区,可能与栖息地建设前的水产养殖活动、候鸟栖息活动、周边农业活动和水动力条件有关;两个区域各采样点的重金属地累积指数均小于0,无明显重金属累积风险;两个区域综合潜在生态风险指数均小于150.00,各采样点单项潜在生态风险指数均小于40.00,均属于低潜在生态风险等级。通过研究区与其他滨海自然湿地中重金属特征对比研究发现,本研究区域中的主要生态风险因子是Hg,其次是Cd,后续需要更多的关注。  相似文献   

Patterns of waterbird community composition across a natural and restored wetland landscape mosaic,Yellow River Delta,China   总被引：1，自引：0，他引：1  

Donglai Li  Sihang Chen  Lei Guan  Huw Lloyd  Yueliang Liu  Juanzhang Lv  Zhengwang Zhang 《Estuarine, Coastal and Shelf Science》2011

Habitat restoration can help mitigate the extensive loss and degradation of estuarine and coastal wetlands that have consequently eroded the integrity of many migratory flyways and wintering habitat for waterbird populations. Assessing the impact of restoration strategies however relies on empirical data on waterbird community distribution patterns across natural and restored wetland components. We conducted habitat and waterbird surveys across six natural and restored wetland regions in the Yellow River Delta Nature Reserve (YRDNR), eastern China, between 2007 and 2009. We recorded 93 waterbird species, including populations of 21 global conservation importance species. Community composition was stratified into distinctive clusters with compositional structure changing across these natural, modified and restored wetland components. NMDS ordination revealed that waterbird communities in restored wetlands were significantly different from those in natural and modified wetland components. Community distribution patterns were strongly influenced by environmental gradients (most noticeably salinity), water-level regulation, vegetation composition and differences in protected status. We found marked temporal patterns in waterbird community composition, which may be predictable for the different wetland components across the YRDNR landscape. Our study highlights the conservation benefits of restoring smaller wetland components in improving the ecological integrity of the wider wetland landscape mosaic for waterbird populations. A more coherent and intensive landscape management of water-level regulation and restoration of salinity gradients will be fundamental for wetland and waterbird conservation throughout the YRDNR.  相似文献   

Reduced seabird night strikes and mortality in the Tristan rock lobster fishery     

《African Journal of Marine Science》2013,35(4):589-592

The main impact of the fishery for Tristan rock lobster Jasus tristani on seabirds at the Tristan archipelago and Gough Island is through night strikes, when petrels collide with a ship after being disorientated by its lights. Tristan fishery observers have kept records of night strikes on the MV Edinburgh since the 2010/2011 fishing season. Over the last three years, 723 seabirds from nine species were recorded coming aboard the fishing vessel, with at least 39 (5.4%) birds dying as a result. Birds killed were broad-billed prions Pachyptila vittata (41%), common diving petrels Pelecanoides urinatrix (23%), and storm petrels (Pelagodroma marina and Fregetta grallaria/tropica 36%). All these species are listed as Least Concern globally, and the numbers killed per year are <0.1% of the island populations. The captain and crew of the Edinburgh are aware of the problem posed by deck lights at night, and attempt to keep external lighting to a minimum. As a result, the numbers of birds coming aboard vessels in this fishery have decreased from an average of 130 birds per night in 1989 to less than two birds per night in 2010–2013. Currently, most incidents occur during exceptional events when circumstances require deck lights to be lit at night. Consideration should be given to banning fishing operations at night, at least on misty nights.  相似文献   

黄河三角洲浅海滩涂湿地鸟类多样性调查研究     

贾文泽  田家怡  王秀凤  潘怀剑 《海洋科学进展》2002,20(2):53-59

1 996— 1 998年、1 997— 1 999年分别对黄河三角洲及其湿地鸟类多样性进行了全面调查 ,分析了浅海滩涂湿地鸟类种群组成、区系组成、季节居留型 ,研究了鸟类多样性及其特点 ,确定了鸟类多样性分布中心 ,提出了加强鸟类多样性保护的建议  相似文献   

吊舱式直升机频率域电磁系统 在广东龙门地区的勘查效果   总被引：1，自引：0，他引：1  

王卫平  方迎尧  郑广如 《物探与化探》2007,31(6):546-550

以2005年广东龙门地区1:5万比例尺的直升机航空电磁、磁综合测量资料为基础,并结合地质矿产资料,对广东龙门地区的航磁异常特征、航空电磁异常特征与矿产的关系进行了分析与研究.尤其是利用本次工作研究的电磁异常特征分类法对该区的航空电磁局部异常进行了分类,有效地识别了电磁干扰异常,优选了对找矿有意义的电磁异常.经过对优选的3处局部异常进行地面查证,空地异常对应良好,并指出了多处对找矿有意义的地下良导体.  相似文献   

Age of the pterosaur and web-footed bird tracks associated with dinosaur footprints from South Korea   总被引：2，自引：0，他引：2  

Cheong-Bin Kim  Min Huh  Chang-Sik Cheong  Martin G. Lockley  Ho-Wan Chang 《Island Arc》2003,12(2):125-131

Abstract   An absolute age has been determined for the Cretaceous Uhangri Formation in which web-footed bird tracks, pterosaur tracks and dinosaur tracks have been discovered recently. This combined track discovery is a first from Asia. There is one other similar find in the world, however, the Uhangri site is greater in abundance and frequency. Moreover, the size of the pterosaur tracks indicates that the track maker had a wingspan of 10 m or more. Well-preserved tuffaceous rocks in the formation made it possible to measure geological age by Rb–Sr and K–Ar methods. Rb–Sr whole rock ages for the volcanic rocks are: 96.0 ± 2.5 Ma (MSWD = 0.354) for lapilli andesitic tuff, 81.0 ± 2.0 Ma (MSWD = 0.296) for felsic tuff and 77.9 ± 4.1 Ma (MSWD = 4.41) for Hwangsan welded tuff. K–Ar ages are younger, 83.2–68.8 Ma. The layer containing fossil tracks of pterosaurs and web-footed birds are preserved in black shale sandwiched by the lapilli andesitic tuff and felsic tuff, and are thus 96–81 Ma in age. Dinosaur footprints are dated at 96–78 Ma. Thus the pterosaurs, web-footed birds and dinosaurs coexisted in the same environment from Cenomanian to Campanian time.  相似文献   

辽西中生代含鸟层及上下层位的划分和时代     

李亚平  董国义  范国清 《国土资源》1998,(3)

辽宁西部中生代地层发育,在国内外同期地层研究中占有重要地位。辽西中生代鸟化石的发现,具有重要的科学价值。含鸟层位包括上侏罗统义县组含鸟层和下白垩统九佛堂组含鸟层。现共鉴定出鸟类化石１１个属１４个种,其中义县组鸟化石４个属６个种,地位最为重要。鉴于此,将义县组下部的沉积层划分出来,并建立了四合屯组,该组对寻找鸟类的祖先具有重要的意义。原土城子组一段具有组级岩石地层单位意义称为蒙古营子组。  相似文献   

内蒙古包头市阿善遗址鸟类化石     

侯连海  张子慧 《地质通报》2004,23(8):784-789

研究表明，内蒙古包头市阿善遗址的鸟类化石总计有5目7科10属10种鸟类，其中赤嘴潜鸭、白枕鹤和骨顶鸡为中国鸟类首次化石记录。阿善遗址鸟类群除3种为鸡形目地栖者外，其余全为涉水鸟类，是中国迄今为止首次发现的以水鸟为主体的史前时期鸟类群。这些鸟类化石对研究遗址的生态环境、气候变化以及鸟类地理分布、迁徙和演化等都有重要意义。  相似文献