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三江平原环型湿地土壤温度梯度的研究 被引量:32
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作者 刘吉平 杨青 吕宪国 《湿地科学》 CSCD 2005年第1期42-47,共6页
三江平原环型湿地是低温 (碟型洼地 )和高温 (岛状林 )两种环境组合的典型区 ,为了研究三江平原环型湿地土壤温度梯度特征 ,对环型湿地 4种群落的土壤温度进行了观测。结果表明 ,由环型湿地的中心到边缘 ,土壤温度逐渐升高 ,土壤温度垂... 三江平原环型湿地是低温 (碟型洼地 )和高温 (岛状林 )两种环境组合的典型区 ,为了研究三江平原环型湿地土壤温度梯度特征 ,对环型湿地 4种群落的土壤温度进行了观测。结果表明 ,由环型湿地的中心到边缘 ,土壤温度逐渐升高 ,土壤温度垂直变异由大逐渐减小。各群落深层土壤温度日变化不明显 ,而季节变化较明显 ,不同群落间深层土壤温度水平变异和垂直变异差异以 6月最大 ,8月和 10月份差异较小。这是由于环型湿地的中心到边缘 ,土壤层的厚度逐渐变薄 ,土壤水分含量逐渐降低 ,泥炭层的厚度逐渐变薄以至消失 ,冻结层融解时间逐渐推迟造成的。环型湿地中心的致冷效应有利于有机质的积累和保持环型湿地生态系统的稳定性。研究环型湿地的土壤温度梯度有助于从水热角度来进一步揭示沼泽湿地的生态环境效应 ,为湿地的保护及合理利用提供科学依据。 展开更多
关键词 湿 湿 10 湿
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珠江口淇澳岛红树林湿地变化及调控对策研究 被引量:50
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作者 王树功 黎夏 +2 位作者 周永章 刘凯 陈桂珠 《湿地科学》 CSCD 2005年第1期13-20,共8页
对珠江口内伶仃洋淇澳岛红树林湿地的变化及其驱动力进行了分析。采用的方法包括收集部分历史资料、三个时相段红树林的遥感图像监测和实地样方调查。根据 2 0 0 4年最新遥感测算 ,大约有 2 0 0hm2 红树林生长在该岛 ,这些红树林是珠江... 对珠江口内伶仃洋淇澳岛红树林湿地的变化及其驱动力进行了分析。采用的方法包括收集部分历史资料、三个时相段红树林的遥感图像监测和实地样方调查。根据 2 0 0 4年最新遥感测算 ,大约有 2 0 0hm2 红树林生长在该岛 ,这些红树林是珠江口重要的生态系统 ,但已受到强烈人为干扰。在过去近 2 0年里 ,约 77hm2 的天然红树林被毁掉 ,用于水产养殖、城镇基础设施建设。近些年来研究区红树林面积不断增加 ,尤其是自 1999年实行红树林人工恢复工程以来 ,新引种的红树林 (无瓣海桑Sonneratiaapetala)得以重建。但是淇澳岛红树林斑块的空间格局和种的构成发生了变化 ,红树林群落植物多样性明显减弱。在综合分析基础上 ,根据生态系统管理的思想 ,提出了以构建典型的红树林生态序列和红树林湿地植被多样性为目标的淇澳岛红树林湿地生态系统恢复和建设的建议。 展开更多
关键词 湿 湿 2004 1999
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松嫩平原湿地动态变化及其驱动力研究 被引量:46
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作者 郭跃东 何艳芬 《湿地科学》 CSCD 2005年第1期54-59,共6页
利用 1986年和 2 0 0 0年的遥感影像解译得到的土地利用图 ,提取出松嫩平原湿地动态变化信息。根据土地利用变化动态度模型 ,湿地动态变化主要表现为湖泊、沼泽、河流等天然湿地的减少及人工湿地面积的增加 ,其中天然湿地类型的湖泊和... 利用 1986年和 2 0 0 0年的遥感影像解译得到的土地利用图 ,提取出松嫩平原湿地动态变化信息。根据土地利用变化动态度模型 ,湿地动态变化主要表现为湖泊、沼泽、河流等天然湿地的减少及人工湿地面积的增加 ,其中天然湿地类型的湖泊和沼泽变化最为显著 ;质心模型分析指出湿地的空间变化趋势主要为质心相对朝东北方向偏移的趋势 ,湖泊和沼泽在西南部的减少是其主要原因 ;湖泊和沼泽的转移变化信息表明 ,湖泊面积的减少主要是退化为盐碱地和沼泽 ,而沼泽主要是转化为农田。松嫩平原湿地动态变化存在显著的自然和人为方面的驱动力因素 ,自然因素为湿地的退化提供了内在动因 ,而人为因素则加速了湿地的退化和转化 ,同时自然和人为因素之间存在着反馈机制。 展开更多
关键词 2000 1986 湿 湿 湿 西 退
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Analysis of water vapour flux between alpine wetlands underlying surface and atmosphere in the source region of the Yellow River
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作者 Yan Xie Jun Wen +2 位作者 Rong Liu Xin Wang DongYu Jia 《Research in Cold and Arid Regions》 CSCD 2018年第4期305-316,共12页
An underlying wetland surface comprises soil, water and vegetation and is sensitive to local climate change. Analysis of the degree of coupling between wetlands and the atmosphere and a quantitative assessment of how ... An underlying wetland surface comprises soil, water and vegetation and is sensitive to local climate change. Analysis of the degree of coupling between wetlands and the atmosphere and a quantitative assessment of how environmental factors influence latent heat flux have considerable scientific significance. Using data from observational tests of the Maduo Observatory of Climate and Environment of the Northwest Institute of Eco-Environment and Resource, CAS, from June 1 to August 31, 2014, this study analysed the time-varying characteristics and causes of the degree of coupling(Ω factor)between alpine wetlands underlying surface and the atmosphere and quantitatively calculated the influences of different environmental factors(solar radiation and vapour pressure deficit) on latent heat flux. The results were as follows:(1) Due to diurnal variations of solar radiation and wind speed, a trend developed where diurnal variations of the Ω factor were small in the morning and large in the evening. Due to the vegetation growing cycle, seasonal variations of the Ω factor present a reverse "U" trend. These trends are similar to the diurnal and seasonal variations of the absolute control exercised by solar radiation over latent heat flux. This conforms to the Omega Theory.(2) The values for average absolute atmospheric factor(surface factor or total) control exercised by solar radiation and water vapour pressure are 0.20(0.02 or 0.22) and 0.005(-0.07 or-0.06) W/(m2·Pa), respectively. Generally speaking, solar radiation and water vapour pressure deficit exert opposite forces on latent heat flux.(3) At the underlying alpine wetland surface, solar radiation primarily influences latent heat flux through its direct effects(atmospheric factor controls). Water vapour pressure deficit primarily influences latent heat flux through its indirect effects(surface factor controls) on changing the surface resistance.(4) The average Ω factor in the underlying alpine wetland surface is high during the vegetation growing season, with a value of 0.38, and the degree of coupling between alpine wetland surface and atmosphere system is low. The actual measurements agree with the Omega Theory. The latent heat flux is mainly influenced by solar radiation. 展开更多
关键词 ALPINE wetland the source region of the Yellow River latent heat FLUX solar radiation WATER VAPOUR pressure DEFICIT
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基于3S技术的朝阳港潟湖湿地景观格局演变研究 被引量:16
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作者 谷东起 赵晓涛 +1 位作者 夏东兴 丰爱平 《海洋学报》 CAS CSCD 北大核心 2005年第2期91-97,共7页
在朝阳港湖湿地景观分类体系基础上,利用3S技术对多时相的湖湿地景观格局进行了定量分析,结果表明,从1954年到2002年人工景观面积增加了532 hm2,景观格局指数呈现出景观多样性和均匀度增加、优势度下降的趋势;湖总体斑块密度从0 0... 在朝阳港湖湿地景观分类体系基础上,利用3S技术对多时相的湖湿地景观格局进行了定量分析,结果表明,从1954年到2002年人工景观面积增加了532 hm2,景观格局指数呈现出景观多样性和均匀度增加、优势度下降的趋势;湖总体斑块密度从0 017 4 个/hm2 增加到0 034 6个/hm2,廊道密度从0 69 54 m/hm2 增加到22 05 640m/hm2,景观破碎化程度逐渐增强. 湖湿地景观格局变化与人类的干扰活动密切相关,因此在湖湿地资源保护中合理调控人类的干扰活动尤为重要. 展开更多
关键词 3S 湿 湿 2002 1954
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松嫩平原盐沼湿地冻融期水盐动态研究——吉林省长岭县十三泡地区湖滩地为例 被引量:24
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作者 郑冬梅 许林书 +1 位作者 罗金明 包春红 《湿地科学》 CSCD 2005年第1期48-53,共6页
以吉林省长岭县十三泡地区湖滩地为例 ,选取有代表性的月份进行定位观测、实验和对比分析 ,研究了冻融期盐沼湿地水盐运移的特殊规律性。研究表明 ,盐沼湿地冻结期 ,由于冻层的存在 ,土体内产生的温度梯度、水势梯度 ,是冬季水盐积累的... 以吉林省长岭县十三泡地区湖滩地为例 ,选取有代表性的月份进行定位观测、实验和对比分析 ,研究了冻融期盐沼湿地水盐运移的特殊规律性。研究表明 ,盐沼湿地冻结期 ,由于冻层的存在 ,土体内产生的温度梯度、水势梯度 ,是冬季水盐积累的驱动力。在冻结期 ,冻层水盐自底层向上迁移 ;融冻期 ,冻层自地表向下及自暖土层向上双向融化 ,在冻层形成上层滞水 ,在冻层之下水盐从下向冻层迁移冻结。冻融期间盐沼湿地水盐迁移的热力学机制是松嫩平原土壤盐化发生机制的重要组成部分。 展开更多
关键词 湿
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中国湿地资源特征、现状与生态安全 被引量:72
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作者 刘红玉 《资源科学》 CSSCI CSCD 北大核心 2005年第3期54-60,共7页
湿地作为一种重要的自然资源,具有独特的自然属性特征。中国湿地资源的基本特点表现在资源的有限性、区域性和差异性、整体性和系统性以及功能性等方面。随着人类活动影响,中国湿地资源丧失严重,生物多样性急剧下降。在许多典型区域已... 湿地作为一种重要的自然资源,具有独特的自然属性特征。中国湿地资源的基本特点表现在资源的有限性、区域性和差异性、整体性和系统性以及功能性等方面。随着人类活动影响,中国湿地资源丧失严重,生物多样性急剧下降。在许多典型区域已经威胁到区域生态安全问题。本文在阐述中国湿地资源特征和现状基础上,进一步利用生态足迹法,对典型湿地区域的湿地资源现状和生态安全进行了评估。结果显示,某些重要的湿地分布区出现生态赤字,生态安全呈下降趋势,区域健康和可持续发展受到影响。 展开更多
关键词 湿 湿
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利用多时相Landsat影像生成白洋淀湖底DEM的研究 被引量:9
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作者 沈欣 欧阳志云 Jande LEEUW 《地理与地理信息科学》 CSSCI CSCD 北大核心 2005年第2期16-19,共4页
该文使用多时相Landsat影像,以白洋淀地区为例,阐述基于中等分辨率的可见光—近红外遥感影像生成具有较高精度数字高程模型的非常规方法。对覆盖同一研究区的不同时相影像分别进行淹没区与非淹没区的分类,提取不同水位高度时的水域边界... 该文使用多时相Landsat影像,以白洋淀地区为例,阐述基于中等分辨率的可见光—近红外遥感影像生成具有较高精度数字高程模型的非常规方法。对覆盖同一研究区的不同时相影像分别进行淹没区与非淹没区的分类,提取不同水位高度时的水域边界,并以此为相应水位高度的等高线,对获得的等高线进行插值生成数字高程模型(DEM)。这种由一系列遥感影像提取的水域图生成数字高程模型的方法适用于人为干预较少、地形相对简单的湿地或季节性湖泊,可以弥补该类地区数字高程信息不足或精度不够的缺陷。 展开更多
关键词 LANDSAT (DEM) 线 湿
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Mangrove wetlands distribution status identification, changing trend analyzation and carbon storage assessment of China 被引量:2
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作者 Chang Li Fu Wang +5 位作者 Peng Yang Fei-cui Wang Yun-zhuang Hu Yan-lin Zhao Li-zhu Tian Rui-bin Zhao 《China Geology》 CAS CSCD 2024年第1期1-11,共11页
This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are... This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software platform.Furthermore,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST model.Results show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and Macao.The total carbon storage is assessed at 2.11×10^(6) t,with specific regional data provided.Trends since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in China.An important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove restoration.This study is poised to guide future mangroverelated investigations and conservation strategies. 展开更多
关键词 MANGROVE wetland Carbon storage Ecological conservation ArcGIS software platform RESTORATION InVEST model Quantitative analysis Coastal zone of China
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Foraging habitat selection of overwintering Black-necked Cranes in the farming area surrounding the Caohai Wetland, Guizhou Province, China 被引量:4
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作者 Dawei Wu Canshi Hu +2 位作者 Mingming Zhang Zhumei Li Haijun Su 《Avian Research》 CSCD 2020年第1期74-82,共9页
Background: Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane(Grus nigricollis) feeds on crop remains in farmlands;thus,... Background: Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane(Grus nigricollis) feeds on crop remains in farmlands;thus, reasonable conservation management of this type of farmland that surrounds wetlands is critical for the overwintering populations of the Black-necked Crane;however, it is not clear how the Black-necked Crane chooses the foraging land in the farmland.Methods: A thorough field positioning survey of all foraging sites in farmland areas around the Caohai Wetland and a-sampling analysis of habitat selection by the Black-necked Crane were conducted during the winters from 20162017 and 2017-2018.Results: Multiple factors contributed to the selection of foraging habitat in farmlands, i.e., food factors(crop remains and tillage methods) > human disturbance factors(distance to road and settlement) > topography factors(slope aspect), listed according to the strength of influence. Additionally, Black-necked Cranes tend to choose farmland sites where there was no machine tillage, the crop remains were > 500 g/m^2, the distance to residences ranged from 100 to 500 m, the distance to roads ranged from 50 to 100 m, and the slopes exhibited western or eastern aspects. As the winters progressed, the volume of the edible crop remains declined, and the influences of the other main factors also changed, i.e., the factors of human disturbance(distance to road and settlement) became less important, while the effect of the food factor(crop remains) was strengthened. Thus, the foraging sites near the road became more important.Conclusion: The farming area surrounding the Caohai Wetland is very important for the overwintering Black-necked Crane. Food factors and human disturbance factors are the main factors that influence the choice of feeding ground. 展开更多
关键词 Black-necked Crane Caohai wetland in Guizhou FARMLAND around the wetland FORAGING habitat SELECTION OVERWINTERING period
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近20年来淇澳岛红树林湿地景观格局分析 被引量:33
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作者 王树功 黎夏 +2 位作者 刘凯 周永章 陈桂珠 《地理与地理信息科学》 CSSCI CSCD 北大核心 2005年第2期53-57,共5页
该文分析近20a来淇澳岛红树林湿地景观格局演变,采用遥感和GIS相结合的方法,利用遥感图像处理软件ERDAS对3个时相(1988年、1995年、2002年)的LandsatTM遥感图像应用专家系统方法分类;结合ARCGIS8 1,辅助FRAGSTATS3 01景观软件计算斑块... 该文分析近20a来淇澳岛红树林湿地景观格局演变,采用遥感和GIS相结合的方法,利用遥感图像处理软件ERDAS对3个时相(1988年、1995年、2002年)的LandsatTM遥感图像应用专家系统方法分类;结合ARCGIS8 1,辅助FRAGSTATS3 01景观软件计算斑块和类型水平上的景观格局指数。淇澳岛红树林面积呈上升趋势,1988年、1995年和2002年分别为20 16hm2、28 08hm2、57 96hm2;斑块数目从1988年的1个增加到2002年的18个,总斑块密度、平均斑块周长面积比呈上升趋势;平均斑块大小、平均斑块分维数、平均斑块形状指数呈下降趋势。近20a来淇澳岛红树林湿地景观受人为干扰,景观破碎化程度不断扩大,需对湿地多功能景观进行科学调控。 展开更多
关键词 湿 1988 2002 Landsat 1995 ERDAS TM 湿 20a
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Valuation of Air Regulation Service Value in the Honghu Lake Wetland
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作者 Zhou Wenchang Shi Yuhu +4 位作者 Pan Lei Pang Hongdong Zheng Lanying Fu Tian Hu Wenjie 《Meteorological and Environmental Research》 CAS 2017年第2期24-26,30,共4页
To assess the value of air regulation in the Honghu Lake Wetland,a quantitative study was conducted based on existing literatures. Results showed that the total service value of air regulation in the Honghu Lake Wetla... To assess the value of air regulation in the Honghu Lake Wetland,a quantitative study was conducted based on existing literatures. Results showed that the total service value of air regulation in the Honghu Lake Wetland was 254. 52 million yuan/a,which was 11. 6 times of that by previous studies. The net value of fixed greenhouse gases via wetland plants( including carbon emission value from methane emission conversion into carbon dioxide greenhouse gas effect) was 58. 50 million yuan/a,the data indicated that this lake wetland was a strong carbon sink. The value of oxygen released by the wetland ecosystem was 176. 51 million yuan/a,and the value of regulating air humidity and temperature was 19. 51 million yuan/a. The net value of greenhouse gases fixed by the Honghu Lake Wetland vegetation,the value of released oxygen,and the value of lifting air humidity and temperature regulation accounted for 22. 98%,69. 35%,and 7. 70% of the total value of the air regulation services,respectively. 展开更多
关键词 Honghu Lake wetland AIR REGULATION Carbon SEQUESTRATION Oxygen release AIR humidity and temperature REGULATION ECOLOGICAL service value
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Heavy Metals Removal from Swine Wastewater Using Constructed Wetlands with Horizontal Sub-Surface Flow 被引量:5
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作者 Jorge A. Cortes-Esquivel Germán Giácoman-Vallejos +2 位作者 Icela D. Barceló-Quintal Roger Méndez-Novelo María C. Ponce-Caballero 《Journal of Environmental Protection》 2012年第8期871-877,共7页
The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers... The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers. and Eleocharis cellulosa) and two different sizes of filter media (5 and 15 mm) using a horizontal sub-surface flow constructed wetland. From the results, a significant difference was observed in the removal efficiency of Cu and Zn with respect to different hydraulic retention times. The best results were obtained in the HRT of 96 hours for Zn where 96% removal of Zn with Typha domingensis Pers. specie with gravel of 15 mm (experimental unit 6) was achieved. For Cu, at 72 hours of HRT, the efficiency was nearly 100% in five of the six study units (1, 2, 3, 5 and 6). In contrast, in experimental unit 4 with gravel of 15 mm and without plants, only 86% Cu removal was achieved. 展开更多
关键词 Swine Wastewater TYPHA domingensis Pers. ELEOCHARIS cellulosa Heavy Metals Constructed wetlandS HORIZONTAL Sub-Surface Flow
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湖北省湿地冬季水鸟多样性研究 被引量:34
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作者 胡鸿兴 康洪莉 +6 位作者 贡国鸿 朱觅辉 郑文勤 吴法清 何定富 李振文 耿栋5 《长江流域资源与环境》 CAS CSSCI CSCD 北大核心 2005年第4期422-428,共7页
报道了2004年1~4月湖北冬季水鸟调查结果,记录水鸟 66 种,种群数量 59 613 只,分属8目15科,其中列入国家重点保护的一级鸟类 4 种,115 只,国家二级 7 种,2 968 只.分析了冬季水鸟群落结构、分布和种群变动,并用生物多样性指数、物种丰... 报道了2004年1~4月湖北冬季水鸟调查结果,记录水鸟 66 种,种群数量 59 613 只,分属8目15科,其中列入国家重点保护的一级鸟类 4 种,115 只,国家二级 7 种,2 968 只.分析了冬季水鸟群落结构、分布和种群变动,并用生物多样性指数、物种丰富度与生物量3个不同的测度指标对其中12个湖泊的水鸟群落进行了评价,认为沉湖、梁子湖、龙感湖和网湖是较为成熟稳定的群落;并从沉湖东方白鹳(Ciconia boyciana)、龙感湖白头鹤(Grus monacha)、洪湖鸭科水鸟近40年的种群动态探讨了湿地水鸟现状,认为种群衰退趋势明显、湿地干扰和威胁严重.对此提出了加强湿地保护区的建设,理顺管理体制,合理规划与发展湿地产业和保护湿地资源对策. 展开更多
关键词 2004 湿 湿 退 湿
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Spatial-temporal analysis of wetland landscape pattern under the influence of artificial dykes in the Yellow River delta 被引量:1
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作者 Xin Fu Gaohuan Liu +2 位作者 Siyue Chai Chong Huang Fadong Li 《Chinese Journal of Population,Resources and Environment》 2013年第2期109-117,共9页
The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes o... The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period. 展开更多
关键词 artificial DYKES COASTAL wetland COASTAL zone of the YELLOW River DELTA LANDSCAPE pattern spatial-temporal analysis
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Study on the Heavy Metals Removal Efficiencies of Constructed Wetlands with Different Substrates 被引量:1
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作者 Mengzhi CHEN Yingying TANG +1 位作者 Xianpo LI Zhaoxiang YU 《Journal of Water Resource and Protection》 2009年第1期22-28,共7页
In this study constructed wetlands (CWs) were used to remove three heavy metals (Zn, Cu and Pb). The two tested substrates were made of coke and gravel, respectively. First order dynamic model was appropriate to descr... In this study constructed wetlands (CWs) were used to remove three heavy metals (Zn, Cu and Pb). The two tested substrates were made of coke and gravel, respectively. First order dynamic model was appropriate to describe removing of Zn and Cu. The experimental results showed that first dynamic removal rate constants of Zn in CWs with coke and gravel were 0.2326 h-1 and 0.1222 h-1, respectively. And those of Cu in CWs with coke and gravel were 0.2017 h-1 and 0.3739 h-1. However, removal efficiencies of Pb in the coke system and the gravel system were within 95-99%, so the first order dynamic model failed to fit the experimental data because the hydraulic resident times of Pb did not affect outlet concentration of Pb. From the removal rate constants, it is found that the coke and gravel system have different absorption efficiencies of heavy metal pollutants. Therefore, it is suggested that the removal efficiencies of heavy metals are influenced by the choice of substrates to some extent. 展开更多
关键词 SUBSURFACE Flow CONSTRUCTED wetlandS First Order Dynamic Model Heavy Metal POLLUTANT Substrate Removal Efficiency
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Study on the Functional Zoning Modes of Urban Wetland Parks
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作者 林晓 栾春风 《Journal of Landscape Research》 2009年第7期62-66,共5页
Functional zoning is a critical phase in the planning of parks.Through summarizing and analyzing the functional zoning modes of different urban park types in China,as well as comparing to the functional zoning modes o... Functional zoning is a critical phase in the planning of parks.Through summarizing and analyzing the functional zoning modes of different urban park types in China,as well as comparing to the functional zoning modes of nature reserves,famous scenic areas and overseas national parks,the functional zoning modes of urban wetland parks in China were elaborated in this study,the assumption of further sectorization were put forward,and theoretical supports were sought for more scientific and operable functional zoning of urban wetland parks. 展开更多
关键词 wetland PARK Functional ZONING BIOSPHERE Core ar ea BUFFER zone Transition area
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泉州湾红树林湿地人工生态恢复的研究 被引量:28
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作者 叶功富 范少辉 +4 位作者 刘荣成 张建生 洪志猛 崔丽娟 林宏斌 《湿地科学》 CSCD 2005年第1期8-12,共5页
红树林为热带和亚热带海岸潮间带特有的植被类型 ,但因人为的破坏 ,我国红树林面积和资源锐减 ,现有红树林湿地中不少处于退化状态 ,开展红树林湿地生态恢复具有重要意义。在福建泉州湾红树林湿地开展了不同滩涂立地、造林方式、栽植不... 红树林为热带和亚热带海岸潮间带特有的植被类型 ,但因人为的破坏 ,我国红树林面积和资源锐减 ,现有红树林湿地中不少处于退化状态 ,开展红树林湿地生态恢复具有重要意义。在福建泉州湾红树林湿地开展了不同滩涂立地、造林方式、栽植不同密度下桐花树、秋茄的生态恢复试验 ,进行了各种造林方法的经济投入分析。结果表明 ,在海岸湿地进行植被恢复和造林地规划时 ,应重视滩涂潮汐浸淹深度的影响 ,尽量选择浅滩地、中滩地营造红树林。桐花树移植天然小苗 ,秋茄采用胚轴插植方法造林 ,成活率达 83%以上。造林初植密度以 0 .5m× 1.0m适当密植为宜。红树人工林通过消浪、促淤、降低风速等作用达到了保护海岸的目的。 展开更多
关键词 湿 湿
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The Habitat Structure of Lukanga Ramsar Site in Central Zambia: An Understanding of Wetland Ecological Condition
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作者 Harry Chabwela Chansa Chomba Loyd Thole 《Open Journal of Ecology》 2017年第6期406-432,共27页
A field survey was carried out to determine the vegetation structure of the Lukanga Swamp Ramsar site in central Zambia. The aim of the study was to identify the different vegetation communities, species composition a... A field survey was carried out to determine the vegetation structure of the Lukanga Swamp Ramsar site in central Zambia. The aim of the study was to identify the different vegetation communities, species composition and distribution patterns for improved habitat management. Sampling was conducted in all recognizable vegetation communities. The results of the survey showed that the swamp was a littoral palustrine wetland predominantly characterized by the dominance of Leersia hexandria Swartz (42.02%), Typha capensis Rohrb (62.43%), Phragmites australis (Cav.) Trin. ex Steud (33.61%), Aeschynomeme fluitans Peter (31.58%) and Polygonum senegalense Meisn (48.8%). The occurrence of Vossia cuspidata Griff and Cyperus papyrusL was restricted to small and isolated locations. Short Termitaria was generally covered by Acrocerus macrum Stapf (35.25%) while tall Termitaria was dominated by Panicum maximum Jacq. (26.00%). The most important woody plant species included Combretum ghasalense Engl. et Diels (I. V = 62.88), Pseudolachnostylis maprouneifolia Pax ((I. V = 90.48), Albizia adianthifolia (Schmacher) W.F. Wight (I. V = 135.63) Isoberlinia angolensis Hyle and Brenan (I. V = 87.25). The current structure of the hydrophytes composition observed in this study was an indication of a generally silting wetland, while the dominant occurrence of understorey woody plants in the surrounding vegetation signified degraded miombo vegetation. It was concluded that the ecological status of wetland habitat was potentially threatened by mainly anthropogenic activities such as;wildfires, and unsustainable exploitation of surrounding vegetation. Further research is required to examine water flows, eutrophication and the long-term effects of deforestation on the ecological functioning of the wetland. 展开更多
关键词 Aquatic MACROPHYTES wetland Habitat Brachystegia Woodland PALUSTRINE SWAMP Sedimentation Environmental Flows wetland Fires and OVEREXPLOITATION
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A Novel Protection and Utilization Pattern for Urban Wetland—As an Example of Hemu Wetland in Hangzhou, China
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作者 Nongnong Shi Minger Ye +4 位作者 Tongfei Lai Zhiming Yu Yunli Pan Mengying Yu Xiaoqi Zhou 《Journal of Water Resource and Protection》 2015年第4期300-311,共12页
This paper proposes an innovative plan and its implement strategy of Hemu urban wetland. The plan takes into consideration its historical background and current status, its protection significance, strategies, solutio... This paper proposes an innovative plan and its implement strategy of Hemu urban wetland. The plan takes into consideration its historical background and current status, its protection significance, strategies, solutions and support conditions. It highlights the landscape characteristics of rivers and lakes, and restores its historical flood prevention functions and climate regulation for the city. Especially, this paper proposes to achieve the restoration of “Mulberry-sided Fish Pond” farming style—an important agricultural heritage created by the ancestors inside the wetland, which is a unique and creative way to use low land for ecological agriculture and cycling economy. The proposed wetland sewage treatment schemes would be of practical importance to improve and enhance the ecological environment and promote the construction of ecological civilization in the region. The “Two zones—One block and Three complexes” protection and utilization plan is reasonable and feasible. It fully presents the functions of the wetland for its production, living, life forms and ecology, and is characterized by joint protection of the wetland by original residents and social public. This will result in active, instead of passive, wetland protection, like turning a “blood transfusion protection” to “hematopoietic protection”, which reflects the sustainable development. The paper offers valuable information and strategies for planning and development of urban wetland. 展开更多
关键词 Urban wetland Protection and Utilization Mulberry-Sided Fish POND ECOSYSTEM Two ZonesOne Block and Three COMPLEXES
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