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41.
高山湖泊对于全球气候变化及人类影响是一个极为敏感的参照系统.九寨沟国家级自然保护区长海作为一个独特的高山湖泊,研究其浮游植物群落结构及其与环境的关系,评估其水质现状及影响因素,有着重要的意义.本文于2014年7月对长海浮游植物群落结构进行了研究.全湖共布设12个采样点,并在中心采样点进行了垂直分层采样.本次调查共发现浮游植物6门38属63种,平均丰度为6.98×10~5cells/L,平均生物量为0.31 mg/L.浮游植物的水平分布差异不大;在垂直分布上,浮游植物的丰度从表层0.5 m至水下50 m呈现先增加后减少的趋势,在20 m水深处达到最大.长海浮游植物的优势种是长海小环藻(Cyclotella changhai)和飞燕角甲藻(Ceratium hirundinella),长海小环藻数量较多,飞燕角甲藻生物量较大.长海浮游植物多样性指数较低,综合各类水质评价方法,可以得出九寨沟长海处于贫-中营养状态.  相似文献   
42.
Water content and movement in soil profile and hydrogen isotope composition (δD) of soil water, rainwater, and groundwater were examined in a subalpine dark coniferous forest in the Wolong National Nature Reserve in Sichuan, China, following rainfall events in 2003–2004. Light rainfall increased water content in the litter and at soil depth of 0–80 cm, but the increased soil water was lost in several days. Heavy rainfall increased soil water content up to 85% at depths of 0–40 cm. Following the light rainfall in early spring, the δD of water from the litter, humus, illuvial, and material layers decreased first and then gradually reached the pre‐rainfall level. In summer, light rainfall reached the litter humus, and illuvial layer, but did not hit the material layer. Heavy rainfall affected δD of water in all layers. The δD of soil interflow slightly fluctuated with rainfall events. The δD of shallow groundwater did not differ significantly among all rainfall events. Light rainfall altered the shape of δD profile curve of water in the upper layer of soil, whereas heavy rainfall greatly affected the shape of δD profile curve of water in all soil layers. Following the heavy rainfall, preferential flow initially occurred through macropores, decayed plant roots, and rocks at different depths of soil profile. With continuing rainfall, the litter and surface soil were nearly saturated or fully saturated, and infiltration became homogeneous and plug‐like. Forest soil water, particularly in deeper soil profile, was slightly affected by rainfall and, thus, can be a source of water supply for regional needs, particularly during dry seasons. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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福田红树林保护区科普教育模式探讨   总被引:2,自引:2,他引:0  
福田红树林保护区位于深圳湾东北岸,其独特的红树林湿地景观吸引了大量市民及游客前来参观。科普宣传教育是保护区的重要职能之一,保护区管理局应强化服务意识,充分发挥保护区的科普教育资源优势,以满足市民群众的科普知识需求。本文总结了保护区近年来开展科普教育活动的经验教训,分析了当前科普教育模式优点和不足,对今后科普教育模式提出了建议。  相似文献   
45.
In an era of late capitalism and climate crisis, an expanding, heterogeneous network of people find themselves precariously positioned at the edge of disaster. This paper explores how Stop FEMA Now, a coalition of U.S. flood disaster survivors and other coastal homeowners, used social media to challenge neoliberal policies that produced – and then privatized – environmental risk. I find that social media played a crucial and sometimes unexpected role in enabling activists to organize across difference and cohere around an identity that emphasized their multiple layers of vulnerability and responsibilization. Through images that reembedded natural disasters in their political and economic contexts, activists exposed their historic and ongoing abandonment by neoliberal policies and state failures. Ultimately, such abandonments forfeited coastal homeowners to a future marked by fiscal and climate crisis, constituting them as sacrificed citizens. And yet, I also propose that the struggles of sacrificed citizens offer new possibilities for coalitions and pluralisms.  相似文献   
46.
Glaciers are one of the most important land covers in alpine regions and especially sensitive to global climate change. Remote sensing has proved to be the best method of investigating the extent of glacial variations in remote mountainous areas. Using Landsat thematic mapping (TM) and multi-spectral-scanner (MSS) images from Mt. Qomolangma (Everest) National Nature Preserve (QNNP), central high Himalayas for 1976, 1988 and 2006, we derived glacial extent for these three periods. A combination of object-oriented image interpretation methods, expert knowledge rules and field surveys were employed. Results showed that (1) the glacial area in 2006 was 2710.17 ± 0.011 km2 (about 7.41% of the whole study area), and located mainly to the south and between 4700 m to 6800 m above sea level; (2) from 1976 to 2006, glaciers reduced by 501.91 ± 0.035 km2 and glacial lakes expanded by 36.88 ± 0.035 km2; the rate of glacier retreat was higher in sub-basins on the southern slopes (16.79%) of the Himalayas than on the northern slopes (14.40%); most glaciers retreated, and mainly occurred at an elevation of 4700–6400 m, and the estimated upper limit of the retreat zone is between 6600 m and 6700 m; (3) increase in temperature and decrease in precipitation over the study period are the key factors driving retreat.  相似文献   
47.
在紧邻大都市的上海九段沙湿地国家级自然保护区上沙实验区范围内,根据地形地势,潮沟水系走向,因地制宜规划设计一个5km2环保低碳,具有湿地保育、监督管理、科学研究和宣传教育于一体的多功能湿地生态科普园,让久居城市的人们远离喧嚣,营造一种宁静清幽、寓教于乐、回归大自然的亲切感。从设计目标、原则、理念和总体布局等方面阐述了九段沙湿地生态科普园的建设思路,为生态、低碳、环保、科学建设九段沙湿地生态科普园提供参考。  相似文献   
48.
Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas National Nature Reserve, which has potential for such designation, was analyzed quantitatively using scenic beauty estimation(SBE).The landscapes of 19 representative scenic spots in the Kanas National Nature Reserve in summer and autumn were selected as the objects of evaluation.The contributions of different landscape factors to the aesthetic value of the Kanas National Nature Reserve were revealed using a multivariate quantitative model.The main factors affecting the aesthetic value were waterscapes, vegetation, mountains, folk culture and the tourist environment.The t-test and F-test results are extremely significant.According to the results, some suggestions were given for conserving the landscapes in the Kanas National Nature Reserve.  相似文献   
49.
极高海拔地区多为河流发源、冰川发育地,由于地形起伏强烈,且野外考察验证工作困难,传统的遥感信息提取方法很难保证该地区水体及冰川的提取精度。本文基于ASTER影像,运用面向对象的图像信息自动分析方法,对珠穆朗玛峰国家级自然保护区核心区的水体及冰川信息进行了提取研究。为保证信息提取的准确度,将数字高程模型(DEM)及其衍生数据(坡度、坡向),归一化植被指数(NDVI)数据,及有助于区分水体、冰川与其他地物的相关指数(冰雪指数NDSII)及波段运算结果(b1-b3)、(b3/b4)等,分别作为一个波段叠加到原始图像中,使之成为对目标地物光谱特征的有益补充。并对不同类型的水体及冰川进行多级、多尺度分割,以满足其对分割尺度的不同要求。分割完成后,综合考虑目标地物的光谱特征、纹理特征、空间结构特征,根据各特征指数的直方图信息,设定合适的阈值,建立了各水体及冰川类型信息提取的知识规则,并结合实地调查对信息提取的精度进行验证,改进了ASTER遥感影像自动快速提取极高海拔区水体及冰川信息的实用模型。  相似文献   
50.
Only few models for land-cover classification incorporated spectral data into ordinary logistic regression (OL model) in the Mt. Qomolangma (Everest) National Nature Preserve (QNNP) in China. In this study, spectral variables were incorporated into OL model and autologistic regression (AL) model to classify six main land covers. Twelve environmental variables and seven spectral variables of 10,000 stratified random sites in the QNNP were quantified and analyzed; OL model, AL model, OL model with spectral data (OLM model), and AL model with spectral data (ALM model) were estimated. The OLM and ALM models produced better estimates of regression coefficients and significantly improved model performance and overall accuracy for the grassland, sparsely vegetated land, and bare land compared with OL and AL models.  相似文献   
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