青海湖地区人类活动形成的重庆环境问题与治理

上世纪五十年代以来人类大规模的耕地、放牧、捕鱼活动使青海湖地区生态环境遭到严重破坏,数百条小河小溪已不复存在,湖水深37．5m下降到现在的25．3m,1963年-1996年33年间牧草地单位鲜草产量下降了37．4％。恶化的生态环境促使沙暴频繁发生,加速了沙丘迁移,迫使居民数次搬迁。在实施西部大开发战略中,环湖地区生态治理要以退耕还草和牧草地建设为主线,全力推行节水灌溉技术,加强涵养水源和生物多样性保护。     

HISTORICAL DESERTIFICATION PROCESS IN HEXI CORRIDOR, CHINA

1IN TR O D U CTIO NH istoricdaelsertificatiisonnotonlythekeyissueon theinteractiobnetweennatureandhuman proces,sbutalsothemost challenginigssueinthecomplex reltaionshipbetweenhuman andland.Previousl,ymostChinesesci-entistisnthisfieldcarrieoduttheiresearch…     

历史记忆：万里长江飘玉带

同样发源于青藏高原腹地的另一条河流叫长江。     

庖田村抓经济发展促生态环境保护

龙胜各族自治县平等乡庖田村,位于平等乡的东南方,方圆约20多平方公里,该村解放初期,除水田和常耕地外,其余山场是一片片的林海。1958年大放“木材卫星”后,大部分森林被砍伐,加上后来的刀耕火种,各村民组所辖的山场一块块黄土地星罗棋布,随着人口的增长,农户的增加,烧柴量也一年比一年增多,山上的林木一年比一年减少,水土流失一年比     

Assessment of seasonal sedimentation in rain-fed irrigation reservoirs by a hillslope erosion modeling approach

A distributed hillslope model is presented for the computation of seasonal sediment loads flowing into the rain-fed irrigation reservoirs （tanks） from the mountainous catchments in Sri Lanka. The model is based on the subdivision of the catchment into hillslopes and application of a sediment transport capacity equation at hillslope scale and computation of sediment loads transported to the tanks. Coarse and fine sediment loads due to hourly excess rainfall during a season are separately estimated. The model depends on fewer parameters and can be easily calibrated for a tank. The model calibration only requires measurements of coarse and fine sediment loads transported into the tank due to several rainfalls of different intensities from a representative subcatchment of the tank. Coarse sediment loads are measured by using a sediment trap installed across an ephemeral stream draining the subcatchment. Fine sediment loads are obtained by measuring the discharge and accompanied sediment concentrations over the sediment trap. The model is calibrated, verified and applied for an irrigation tank in Sri Lanka to estimate the seasonal sedimentation loads.     

海岸带海陆交互作用过程及其生态环境效应研究进展

海岸带是地球表层物质、能量和信息流通交换最活跃区域之一,具有动态变化的盐度、溶解氧等地球化学梯度,其界面过程体现在大气降水-河水-海水-地下水-沉积物之间的物质循环和能量交换。在人类活动与气候变化双重影响下,海岸带面临着气候灾害、海岸侵蚀、海水入侵、滨海湿地退化、水体富营养化以及重金属、新型污染物等生态环境问题,成为地球科学和环境科学领域研究的热点。本文围绕海岸带水文-生物地球化学循环、人类活动影响下的海岸带环境问题、海岸带环境对气候变化的响应、海岸带海陆交互界面观测新技术新方法4个方面,综述了国内外研究进展与发展趋势,展望了海陆交互作用及其生态环境效应研究的未来发展方向。      

泰来县协调土地利用与建设研究

土地生态环境是指空间大气、地貌、土壤、植被、水资源等自然因素,以及人类活动种种结果对人类活动施加的各种影响在内的各种物质的总和。土地环境是整个生态环境的重要组成部分,在不断地变化、运动、进行周而复始的循环。土地生态环境分析和评价．是通过调查土地环境质量的现状,查清土地环境存在的主要问题。     

关于浙江省国土建设与开发的若干问题

改杭州湾跨海架桥方案为拦海筑坝,建杭州湾大水库,改金塘海峡大桥方案为造陆桥,建甬江口海上水库,清淤造陆,实施生态移民。     

越过地平线

我们生活在同一星球上,由一个决定我们生活的生态、社会、经济和文化关系的微妙而错综复杂的网络,把我们联系在一起,要实现可持续发展,就必须对所有生命依存的生存系统、对彼此作为整个人类大家庭的一分子、以及对我们子孙后代承担更大的责任。——利菲·安南     

矿业城市区域植被恢复与重建的几点思考--以乌海市为例

矿业城市是指先有矿后建城,以矿产开发而建立起来的城市.诸如乌海市、白银市、克拉玛依等均以不同矿种开发而形成的城市.其区域内典型的是植被稀少、生态脆弱、环境恶化,这些都与开采矿产资源人为破坏有关.矿业城市区域植被恢复是一个重大主题,内容广泛,措施千差万别,本文仅以乌海为例.     

人类活动对环境的危害

近年来,世界各地的洪涝、干旱、地震、泥石流、滑坡、森林火灾等灾害事件频频发生.全世界每年因灾害所造成的经济损失数以亿计,灾害大多与人类的活动,特别是与人类经济-工程活动有关.结合灾害事例,特别是地质灾害事例,从生态、气候、城市及地质环境等方面加以论述,阐明人类经济-工程活动加快诱发了对环境的危害,希望引起人们,特别是政府部门和有关专家对环境保护的重视.     

宽甸县水土流失灾害与防治对策

宽甸县处于新构造运动强烈上升区,境内峰峦叠嶂,山势陡峻,沟深谷狭,暴雨频繁,地质环境十分脆弱;加之森林大量砍伐,陡坡开荒严重,垦植指数过高,超载养蚕放牧,滥采乱挖猖獗,使生态环境遭到严重破坏,水土流失程度日益加剧。严重的水土流失,导致水库淤积,河道堵塞,土层变薄,地力下降,洪水泛滥,灾害频繁,给国民经济和社会发展造成巨大损失。本文阐述了宽甸山区水土流失的形成因素和危害现状,并因地制宜提出了水土流失灾害的防治对策     

长江三峡水库蓄水后的首发微震群活动

长江三峡水库2003年5月19日正式蓄水，6月7～30日发生可定位0级以上地震131次，其中最大为ML2．1。经分析，该微震群活动与水库蓄水有关。     

祁连山-河西走廊地区的现今水平形变

根据祁连山-河西走廊地区的两次GPS测量的结果，研究了该地区在整个欧亚板块运动的背景下的内部水平变形。按照刘百篪对该地区的主要构造的最新研究结果，GPS观测资料覆盖区可划分为5个次级块体(祁连山、阿拉善、塔里木、西宁-兰州、共和次级块体)。除其中共和块体因仅有一个观测点而无法进行研究之外，对其余4个块体用刚体运动加均匀应变模型研究了这些构造块体的相对运动和变形。结果表明，这些块体内的应变参数显著性不高，即该地区的现今水平变形以区内一些次级块体的整体相对运动为主，应变积累只占次要地位。这些次级块体间的边界断裂大多数仍呈现为某种继承性运动，只是在本区西北部的祁连山次级块体与塔里末块体交界部位现今运动表现出与继承性运动不同的性质。由于与该边界有关的两侧块体上的观测点仍嫌不足，这一结论的可靠性尚待进一步验证。     

Sandy Desertification Status and its Driving Mechanism in North Tibet Plateau

As the main body of Qinghai-Tibetan Plateau, North Tibet Plateau is one of three major sandy desertification regions in China and also a representative sandy desertification zone of Qinghai-Tibet Plateau. Accordingly, it is an important region for the study of recent sandy desertification processes and formation mechanism. From such aspects as desertified land types, areas and distributions etc., this paper analyses in detail the sandy desertification status on North Tibet Plateau, and qualitatively and quantitatively deals with the main factors that affect recent sandy desertification processes and the driving mechanism. Research results show that North Tibet Plateau is an important sandy desertificafion region in China characterized with large desertified land areas, diversified types, high severity, extensive distributions and serious damages. Sandy desertification occurrence and development resulted from combined effects of natural factors, anthropogenic factors, natural processes and man-made processes, of which climatic change is the main driving force.     

Impact of Human Activities on Depositional Process of Tidal Flat in Quanzhou Bay of China

As a very important component of a coastal system,tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are highly sensitive to the global change.The Quanzhou Bay,located along the middle part of Fujian coast of China,covers about 136.4km2,and the area of coastal wetland in the entire bay from intertidal to subtidal with 6m of water depth accounts for 96% of the total area.Seven short cores were collected and divided in situ with the interval of 5cm on the coastal wetlands of Quanzhou Bay on April 19,2006.The sediment samples were scattered and the grain sizes were measured by using Mastersizer 2000.Human beings' activities on tidal flat have disturbed the vertical distribution of sediments in stratigraphic sequence and accelerated the sedimentation rates.Grain size analysis results show that the grain size diameters increase and sediment becomes worse sorted towards the sea under the strong human disturbance;Spartina alterniflora can play a role of trapping the fine sediment;but near the bank,the sediment becomes coarse and there are two peak values on frequency curve influenced by the sandpile.The trough formed by human activities along the coastline changes the transport path of water and suspended sediment.The sediments are transported through the trough and deposit in it during the flood;the ebb flow is retarded by the flow output through the adjacent trough,and the deposited sediment can not be re-suspended;then,the sedimentation rate increases.In situ observation show that the sedimentation rate is about 8-10cm/yr.     

用水土融合规律防治土地退化

一、土地退化概述,青海地处青藏高原腹地,自然条件差,土地容量小,发展空间狭窄,是一个典型的干旱、半干旱省区。由于长期受气候变暖和人类活动的影响,造成湿地面积萎缩、风蚀面积增加、草原生态恶化、荒漠生态扩大、水土流失加剧、水旱灾害频发、损失逐年增大、生态灾民增多,以致土地的承载结构发生了变化,能流和物流出现失调,原始土地的生态系统严重退化。全省荒漠化土地面积占国土面积的27．3％,且每年以2000km^2左右的速度扩展,是荒漠化危害最严重的省区之一,青海正在成为一个土地退化的大省。这对人口不断增加、土地容量有限、群众生活贫困的青海省来说,是一个很大的压力,也是面临的一个难题。     

APPLICATION OF ANALYTIC HIERARCHY PROCESS TO ASSESSING THE ECOLOGICAL VULNERABILITY OF WETLANDS IN THE JIANGHAN PLAIN

Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology,waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jiang-han Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the JiangJaan Plain should be paid attention to.     

基于卫星遥感的国家级自然保护区人类活动监测

选用2020年高分卫星影像作为数据源,对河南省境内国家级自然保护区人类活动进行遥感监测,探讨人类活动对河南省境内国家级自然保护区的影响。结果表明:自然保护区内人类活动总面积约占保护区总面积的21%,人类活动影响指数介于0~0.007。不同类型保护区受人类活动干扰程度不同,内陆湿地类型受人类干扰程度最大,其次为地质遗迹类型、野生生物类型,森林生态系统类型受人类活动影响程度最小。