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面向遥感监测的中国湿地区划初步构想 总被引:1,自引:0,他引:1
遥感技术作为对湿地进行监测的现代空间信息技术,在对湿地研究和管理中日益发挥重要作用。我国国土面积广大,在不同地带分布有不同类型的湿地。现有的湿地分类工作尚不能满足对全国开展湿地监测的需要,也缺少地理区划理论的支持。为满足全国湿地遥感动态监测的需要,以现有湿地相关研究为基础,对湿地区划的指标体系、区划的原则、方法以及区划的等级体系进行了讨论,旨在为湿地区划方案的制定和实施提供参考。 相似文献
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江苏盐城海岸湿地景观生态系统研究 总被引:14,自引:2,他引:12
江苏盐城海岸湿地以其景观典犁性成为科学研究的理想区域。根据野外观测与文献资料分析及现场验证相结合的研究方法,基于区域景观格局演变规律进行景观生态分类,进而分析景观生态系统的动力因素、结构、格局、生物多样性特征等。结果表明:盐城海岸湿地景观生态系统生态多样性丰富,景观结构和格局的形成和演化是当地特定的非生物环境(气候、海洋水文和土壤等)、生物作用和人类活动等因素综合作用的结果:景观格局的显著特征是动态变迁的带状景观空间异质性,高、低对比度兼存的景观结构。 相似文献
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Laboratory and numerical studies of wave damping by emergent and near-emergent wetland vegetation 总被引:3,自引:0,他引:3
Wetlands protect mainland areas from erosion and damage by damping waves. Yet, this critical role of wetland is not fully understood at present, and a means for reliably determining wave damping by vegetation in engineering practice is not yet available. Laboratory experiments were conducted to measure wave attenuation resulting from synthetic emergent and nearly emergent wetland vegetation under a range of wave conditions and plant stem densities. The laboratory data were analyzed using linear wave theory to quantify bulk drag coefficients and with a nonlinear Boussinesq model to determine numerical friction factors to better represent wetland vegetation in engineering analysis. 相似文献
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Wen-hui Jie Chun-lei Xiao Ce Zhang En Zhang Jing-yue Li Bing Wang Hai-wei Niu Shuang-fa Dong 《China Geology》2021,4(2):353-363
The environmental change in the wetlands in the southern Mongolian Plateau has important impacts on the environment of North China and even the entire Northeast Asia, from which the global climate change can be understood on a large scale, especially the climate change in the Mongolian Plateau. This study extracted the information on the wetlands from three stages of remote sensing images (also referred to as RS images) of the study area, including Enhanced Thematic Mapper Plus (ETM+) images of 2000, TM images of 2010, and Landsat 8 Operational Land Imager (OLI) images of 2018. As indicated by the extraction results, the area of wetlands decreased from 796.90 km2 of 2000 to 666.24 km2 of 2018 at a rate of 7.26 km2/a. The reduced area is 130.66 km2, which is about 16.4% reduction. And the patch number of wetlands decreased from 731 of 2000 to 316 of 2018 in the study area, approximately 56.8% reduction (415 patches), and the decrease in the area of the wetlands mainly occurred in the northwest endorheic region. In terms of wetland types, the change of the wetlands was dominated by the decrease of lacustrine wetlands, of which the area and patch number decreased by 106.2 km2 and 242, respectively. Furthermore, the area of the lacustrine wetlands decreased at the highest rate of 8.70 km2/a in 2010–2018. From the perspective of spatial distribution, the wetlands in the western part shrunk more notably than those in the eastern part as a whole in the study area. According to local meteorological data, the precipitation gently decreased and the temperature increased (about 1.7°C) from 1975–2018. Overall, the decrease in the area of the wetlands and the temperature rises in the study area were mainly driven by the Mongolian monsoon climate, reduction in precipitation, and human activities. 相似文献
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黄淮海地区湿地水生态过程、水环境效应及生态安全调控 总被引:11,自引:1,他引:11
围绕国家重点基础研究发展计划(973计划)项目“黄淮海地区湿地水生态过程、水环境效应及生态安全调控”,介绍了湿地水生态过程、水环境效应和生态安全调控研究对我国社会与科技发展的意义、研究现状和发展趋势、拟解决的关键科学问题、主要研究内容和研究总体方案。该项研究的最终目标是发展一套集河流、湖沼、河口等湿地系统组分于一体的湿地系统层面上的湿地学理论,解决我国湿地研究面临的一系列基础科学问题,有效协调区域社会经济发展与湿地保护之间的矛盾,为建立不同目标下湿地系统整体调控模式,构建生态、社会和经济相互协调及环境友好型社会体系提供理论和技术支撑。 相似文献