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1.
扎龙国家级自然保护区丹顶鹤巢址的空间分布格局分析 总被引：3，自引：0，他引：3
依据1996年、2003～2007年扎龙自然保护区丹顶鹤(Grus japonensis)巢址分布数据,计算巢址分布的质心、巢址的空间离散度,分析了巢址的空间格局特征;并统计了巢址与芦苇(Phragmites Australis)沼泽的高程.研究结果表明,如果不遇到严重的干扰,扎龙保护区丹顶鹤巢址的质心主要分布在核心区内,每年的偏移主要集中在核心区内部;而在受到火灾干扰的2005年,丹顶鹤巢址的质心几乎迁出了核心区.扎龙湿地丹顶鹤巢址空间分布在此期间具有聚群的特征,2005年以前,丹顶鹤营巢距离逐年缩小;而2005年以后营巢距离又有所增加.丹顶鹤巢址分布在高程142～148 m的占92.03%,而芦苇沼泽分布在高程142～148 m的占82.04%;丹顶鹤巢址分布于坡度小于0.25°的占90.93%,芦苇沼泽分布在坡度小于0.25°的占87.31%;芦苇沼泽和丹顶鹤巢址在高程、坡度上的分布相关性较强,说明芦苇沼泽是扎龙湿地丹顶鹤营巢的重要生境. 相似文献
2.
皖江自然湿地土壤碳密度及其开垦为农田后的变化 总被引：7，自引：1，他引：6
于2005年分别采集了安徽沿江4个淡水湖泊的自然湿地及其周边围垦农田的代表性土壤剖面样品,测定了总有机碳含量,讨论了天然淡水湿地有机碳密度与深度分布特征及其开垦为农田后的变化。结果显示,湿地表层（0～30cm）和全剖面（0～100cm）中的碳密度分别为42．5～57．4t／hm^2和81．5～91．6t／hm^2;而农田则分别为22．4～48．4t／hm^2和41．4～76．5t／hm^2。湿地开垦为农田后,土壤表层和全剖面的土壤有机碳含量明显降低,且有机碳含量的变异性增大。表明湿地开垦为农田后,其碳库失去稳定性。但是,开垦的旱地土壤的有机碳含量和碳密度显著低于开垦的稻田,故湿地开垦为旱地更不利于湿地碳库保护。因而,将湿地垦殖为水田是相对较有利于湿地碳库保护的人为土地利用方式。湿地开垦的碳库损失可能是土壤的大气CO2源效应的主要途径。 相似文献
3.
张掖市黑河流域湿地资源调查与分类 总被引：3，自引：2，他引：1
通过对典型的干旱半干旱区内陆河流域(张掖市黑河流域)湿地综合分类研究表明:①张掖市黑河流域湿地共有2个大类4个类型13个类别,总面积为210420.42hm2,占全市国土总面积的5.02%;②湿地类型和面积从大到小依次为:高山湿地、永久性河流、灌丛湿地、草本沼泽、泛洪平原、内陆盐沼、季节性河流、蓄水区、灌溉区、盐田、永久性淡水湖、池塘、季节性淡水湖;③在行政区域内,肃南县、高台县、临泽县、山丹县、民乐县、甘州区湿地面积分别占全市湿地面积的73.71%、8.29%、5.14%、4.87%、5.54%和2.44%。 相似文献
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I.IntroductionInChina,saltmarshesandmangneswampsaredistributedextensivelyoverti1ecoastalprovincesandropons(Figurel).TheareaofthesetwotyPesofvguatedwetlandswascompLltedbasedonti1erecordsdistributedintheprovincialroportsofti1e"coatmpideinvestigationoncoastalroponandcoastalwetlandresources"carriedoutbetweenl98landl987.Ofthearotu1dl,3oO,ooOacresalloverthecoLnifry,halfofwhicharelocatedaroundti1eBohaiSea,one-tlllrdalongthecoastofYelowSeaandintheChanaiiangestuaryandHangzhouBay,ti1erestsaresitua… 相似文献
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以1990年、2000年、2010年和2015年的Landsat TM/ETM+/OLI影像为数据源,在遥感和地理信息系统技术的支持下,研究了4个时期四川省湿地的面积、景观指数及其变化。研究结果表明,与1990年相比,2015年四川省的湿地总面积减少了29 744.84 hm^2,其中,沼泽湿地面积减少了63 619.19 hm^2,河流湿地面积减少了27 742.60 hm^2;人工湿地面积增加了63 249.19 hm^2;四川省的湿地主要分布在川西北高原湿地区,最主要的湿地类型是沼泽湿地。随着时间的推移,4个时期四川省的湿地斑块数量、斑块密度和香农多样性指数在波动增大,而最大斑块指数在波动减小,面积加权平均斑块分维数变化不大;四川省的湿地向斑块破碎化、形状规则化和类型多样化方向发展。 相似文献
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ANNA JADWIGA KRZYSZOWSKA 《Polar research》1989,7(2):119-131
Studies were performed in Ny-Alesund, Spitsbergen, in June and July 1986 in order to gain an insight into the effect of activities of the polar research station on the nearby environment. It was found that chemical and mechanical factors were the most detrimental to the tundra environment. Fuel oil spills (110 m3 in 1986), which spread via surface and ground waters, were the most damaging of the chemical factors. Domestic sewage polluted the waters of Kolhamna Bay within an area of only 0.5 ha around its outlet in the sea. Vehicles and trampling caused mechanical damage inducing destruction of plant cover and changes in the ground structure; it modified ground moisture, bulk density and depth to the permafrost. The area degraded by human activity in the vicinity of the Ny-Alesund Research Station comprised 45 ha. The human impact around the polar station could be lessened by providing an alarm system to detect leaks and safety embankments around the oil tanks and pipelines, utilizing a settling tank for sewage, providing a simple incinerator for solid wastes, and instructing the inhabitants how to minimise impact on the environment. 相似文献
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滕州市湿地资源现状及保护管理 总被引：1，自引：0，他引：1
山东省滕州市位于山东省南部,境内地形属鲁中南山区的西南麓延伸地带,地势从东北向西南倾斜,依次为低山、丘陵、平原、滨湖。现有湿地面积达1.69万hm^2,占全市面积的11.4%,其中：河流湿地0.22万hm^2,库塘湿地0.27万hm^2,滨湖湿地1.2万hm^2。湿地内生物多样性丰富。在调查分析湿地植物、动物资源现状及存在问题的基础上,提出了湿地资源保护管理对策。 相似文献
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在美国,孤立湿地与可通航水域没有水文联系,被认为不属于《清洁水法》中的“水域”,联邦无权管辖。为此,陆军工程兵团制定“候鸟规则”,作为对孤立湿地行使管辖权的依据。美国“孤立湿地”保护中的“候鸟规则”对我国的启示在于:(1)应从水文学角度界定孤立湿地,孤立湿地是指与其它水体缺乏联系、相对孤立的湿地,这更符合我国湿地政策的现状;(2)人工“孤立湿地”受保护,除了需满足一定的水文条件,还须是野生动物事实上的栖息地,不应限于建立“栖息地档案”意义下的野生动物栖息地或纳入野生动物重要栖息地名录的栖息地;(3)孤立的人工湿地如果是国家重点保护野生动物栖息地,其管辖权应由中央行使;(4)国家重点保护野生动物栖息地外的其他孤立湿地,面积达到35 hm2以上,也应由中央管辖。 相似文献
10.
鄱阳湖自然保护区网络体系建设的探索与尝试 总被引：3，自引：1，他引：2
鄱阳湖是国际重要湿地,是中国最大的淡水湖,也是亚洲最大的水禽越冬地,是白鹤、东方白鹳、鸿雁和小天鹅等珍稀水禽全球最主要的越冬地之一。为保护好鄱阳湖湿地生态系统,保护好鄱阳湖珍稀水禽及其栖息地,江西省人民政府先后在鄱阳湖建立了15个自然保护区(国家级2个、省级2个,其余为县级),这15个自然保护区构成了原有的自然保护区网络体系。由于县级保护区保护管理功能的缺失,使得原有的自然保护区体系发挥的作用十分有限,因此需要尝试建立新的自然保护区网络体系。新的鄱阳湖自然保护区网络体系由鄱阳湖国家级自然保护区的11个保护管理(监测)站和南矶湿地国家级自然保护区的保护管理站共同组成,同时还包括鄱阳湖区越冬候鸟和湿地联合保护委员会、护鸟员和信息员队伍以及奖励机制。目前,新的网络体系存在新建保护监测站职能不明确和人员不足等问题,一定程度上制约了保护管理功能的发挥。为更好地发挥鄱阳湖自然保护区网络体系的作用,加强鄱阳湖自然保护区网络体系的建设十分必要,建议国家和地方政府给予更多的政策和资金支持。 相似文献
11.
云南省第一、二次全省湿地资源调查结果比较研究 总被引：1，自引：0，他引：1
宋永全 《云南地理环境研究》2013,(6):22-26
第一次湿地资源调查,云南省有100 hm2以上各类湿地总面积23.53×104hm2,以河流湿地和湖泊湿地占绝对优势;第二次调查云南省湿地总面积56.43×104hm2,其中自然湿地39.31×104hm2,占湿地总面积69.66%,人工湿地17.12×104hm2,占湿地总面积30.34%。与第一次相比,第二次全省湿地资源调查湿地面积增加32.50×104hm2;第二次调查增加了季节性河流、喀斯特溶洞湿地、洪泛平原湿地、灌丛沼泽、森林沼泽、淡水泉、运河/输水河及水产养殖场8种湿地型,增加湿地面积2.34×104hm2;全省湿地类型自然保护区无论数量还是面积都呈现增加态势,数量共增加12个。 相似文献
12.
Monitoring the Effects of Biological Control of Water Hyacinths Using Remotely Sensed Data: A Case Study of Bangalore, India 总被引：2，自引：0，他引：2
G. Venugopal 《Singapore journal of tropical geography》1998,19(1):91-105
Native to South America, water hyacinths were brought to India as ornamental plants and are now considered as one of the most dreaded aquatic weeds in the country. This plant has infested more than 200,000 ha of fresh water bodies in the country. The Indian Institute of Horticultural Research resorted to biological methods to control these weeds and received favorable results, however, these weeds tend to reinfest the fresh water bodies. For an effective weed control, the infestation needs to be monitored and remotely sensed data have been recommended for this purpose. In this research, SPOT multitemporal data have been used to monitor the infestation of water hyacinths in Bangalore, India. Using Normalised Difference Vegetation Index (NDVI), this study delineated areas of clearing and new infestation in the fresh water tanks in the study area. This study concluded that host specific weevils can eradicate water hyacinths in large areas but that reinfestation remains an ongoing problem. 相似文献
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We investigated the ways in which cormorants (Phalacrocorax spp.) acquire behavioural cues from unpredictable habitats in arid Australia, using 10 years of temporal data on abundance at one wetland, fine-grained habitat and microhabitat use at two wetlands, and broad-scale spatial data from aerial surveys across north-west New South Wales. Abundances were highly variable and cormorants were aggregated at every temporal and spatial scale of observation. Cormorants were associated with short-term patches of food, and apparently travel frequently in a quest for newly formed patches. Movements and abundance of cormorants are linked to boom periods of their prey, and, like many Australian waterbirds, cormorants would benefit from improved water management practices. 相似文献
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A comparison was made of plant cover, carrying capacity and diversity in areas of Monte vegetation at the Biosphere Reserve of Ñacuñán, Mendoza, Argentina, in 1982, 1984 and 1995. Treatments applied in 1981 were: control (untreated plots), selective hand-cutting, roller-chopping, and root-plowing. By 1995, woody cover was lower in root-plowed plots (27%) than in the others treatments (41–51%), and herbaceous cover was similar in treated (28–39%) and untreated areas (26%). Carrying capacity of treated areas (6–8 ha per Large Stock Unit (LSU)) was higher than in the control areas (12 ha LSU−1). Woody species diversity, quantified by the Shannon index, for both areas was similar in the study period (0·62), except in root-plowed sites in 1982 (0·0) and 1995 (1·3). Herbaceous species diversity was similar on treated (0·81) and untreated sites (1·2) in 1995. We could recommend less drastic treatments to improve carrying capacity. 相似文献
16.
The marine ecosystem of Kongsfjorden, Svalbard 总被引：16，自引：1，他引：16
《Polar research》2002,21(1):167-208
Kongsfjorden is a glacial fjord in the Arctic (Svalbard) that is influenced by both Atlantic and Arctic water masses and harbours a mixture of boreal and Arctic flora and fauna. Inputs from large tidal glaciers create steep environmental gradients in sedimentation and salinity along the length of this fjord. The glacial inputs cause reduced biomass and diversity in the benthic community in the inner fjord. Zooplankton suffers direct mortality from the glacial outflow and primary production is reduced because of limited light levels in the turbid, mixed inner waters. The magnitude of the glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground for marine mammals and seabirds. Even though the fjord contains some boreal fauna, the prey consumed by upper trophic levels is mainly Arctic organisms. Marine mammals constitute the largest top-predator biomass, but seabirds have the largest energy intake and also export nutrients and energy out of the marine environment. Kongsfjorden has received a lot of research attention in the recent past. The current interest in the fjord is primarily based on the fact that Kongsfjorden is particularly suitable as a site for exploring the impacts of possible climate changes, with Atlantic water influx and melting of tidal glaciers both being linked to climate variability. The pelagic ecosystem is likely to be most sensitive to the Atlantic versus Arctic influence, whereas the benthic ecosystem is more affected by long-term changes in hydrography as well as changes in glacial runoff and sedimentation. Kongsfjorden will be an important Arctic monitoring site over the coming decades and a review of the current knowledge, and a gap analysis, are therefore warranted. Important knowledge gaps include a lack of quantitative data on production, abundance of key prey species, and the role of advection on the biological communities in the fjord. 相似文献
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西藏湿地资源价值损失评估 总被引：5，自引：0，他引：5
西藏高原独特的自然环境和气候条件,造就了特有的、世界独—无二的高原湿地资源。应用环境经济学的理论与方法,计算了西藏湿地的全部生态环境价值为4023.8068×10^8元/a,以5%的贴现率计算,湿地价值的现值为44261.8748×108元,相当于73.72×10^4元/hm^2。从湿地生态服务功能的价值构成来看,直接使用价值（提供产品和文化功能）约占总价值的24.40%,而间接价值（调蓄洪水、疏通河道、水资源蓄积、土壤持留、净化环境、固定碳和支持功能）则占75.6%,西藏高原湿地退化面积为60.4272×10^4hm^2,相当于年退化面积2.0143×10^4hm^2。已退化湿地损失价值4454.69×10^8元,年损失价值148.49×10^8元。 相似文献
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鄱阳湖湿地生态保护与可持续利用研究 总被引：16，自引：0，他引：16
鄱阳湖湿地是国际重要湿地之一 ,对调蓄长江洪水、候鸟与湿地多样性保护等具有重要意义 ,同时也是全国著名的商品粮基地。湿地保护、恢复与湖区社会经济发展的矛盾随着退田还湖的实施而突现。文中在对鄱阳湖湿地主要生态功能、生态环境问题进行分析评价的基础上 ,提出了湖区湿地保护与可持续利用的对策 相似文献