岱海湖泊萎缩原因分析及流域水生态保护建议

文章通过分析、论证乌兰察布市岱海流域地理特点、径流量分布情况、水热气候趋势和工农业用水量对岱海湖面积的影响,得出自然降水量偏少和气候变暖及工农业用水量增加,是岱海这个内陆湖面积减少的主要原因。据此提出水生态环境保护的具体措施,为地方政府提供正确决策依据。     

岱海湖流域生态质量干湿指标气象评价研究

选取岱海湖流域3个国家一般气象站60年的气象资料,采用Penman-Monteith模型计算出岱海湖流域的参考蒸散量和干湿指数,表征岱海湖流域地表干湿状况。岱海湖流域地表多年平均干湿指数为0.42,属于气候半干旱区。20世纪60、70、90年代湿润指数距平为正距平,气候偏半湿润状态;20世纪80年代后期和21世纪初期（2000—2009年）为负距平,气候偏干旱化。干湿指数主要受降水量、潜在蒸散量、相对湿度、日照时数影响,这些气象因子共同作用影响岱海湖流域气候干湿状况,其中降水量是最主要的影响因子。研究结果可以更好地认识区域气候条件及未来变化方向,为岱海湖的生态评价提供科学参考。     

湿地资源保护及启示

湿地是地球上具有重要环境功能的生态系统和多种生物的栖息地之一。湿地环境中湿地水文、湿地生物地球化学循环与生物对湿地的适应和改造构成、各种因子之间相互依赖、相互协同,构建起湿地的整体功能。湿地生态系统与全球环境变化有着密切的关系。近年来全球湿地生态系统的受损程度十分严重,因此,对湿地生态系统的特殊价值正确认识和积极采取保护措施迫在眉睫。     

新疆湿地资源时空变化特征及其原因分析研究

以新疆第一次（2000年）和第二次（2011年）湿地资源调查中相同的347块湿地为研究对象,利用3S技术,对CBERS、SPOT5和LandsatTM遥感数据进行调查监测,并结合野外实地验证,比较分析新疆湿地资源的时空变化状况及其原因。结果表明,新疆湿地总面积呈减少的趋势,其中河流湿地和沼泽湿地面积增加,分别增加29162 hm²和17130 hm²,湖泊湿地和人工湿地面积减少,分别减少126618 hm²和19391 hm²;各湿地型中,永久性河流、草本沼泽、森林沼泽和季节性咸水沼泽面积有所增加,洪泛平原、内陆盐沼、永久性 淡水湖、季节性淡水湖、季节性咸水湖和库塘湿地面积减少。新疆湿地面积总变化率-7%,各湿地类型中,面积变化率最大的是湖泊湿地（18%）,呈减少趋势;最小的是沼泽湿地（5%）,呈增加趋势。湿地面积变化的主要原因是气候变化和人类活动。     

湿地生态环境监测方法探讨

本文在分析四川湿地现状的基础上,对湿地的监测目的、监测范围、技术手段、监测内容、监测技术指标等问题进行了分析,提出建立我省生态环境监测体系和加强湿地生态环境应用研究的工作思路,为保护湿地生态环境,实现湿地的可持续利用发展提供决策服务.     

湿地生态系统与居地气候关系的研究

针对赤峰市半干旱区的达里诺尔湿地与兴安盟阿尔山湿润地区的湿地，利用湿地的小气候观测资料分别与其相邻的常规气象站的气象观测数据进行对比分析。初步得出以下结论：（1)湿地的“冷湿”效应显著，（2)湿地降水量主要受大气候的影响，与小气候效应无关。（3)位于湿润区的阿尔山湿地比位于半干旱区的达里诺尔湿地更能体现出“冷湿”小气候效应。（4)小气候效应对群落结构、物种分布等方面存在着重要的影响。位于湿润区的阿尔山湿地比位于干旱区的达里诺尔湿地中生、湿生植物偏多，但多样性指数、均匀性指数、物种丰富度低于干旱区的达里诺尔湿地，湿地植物群落的优势度指数要高于达里诺尔湿地，     

长江流域湿地生态系统健康评价

长江流域水资源丰富,农业开发历史悠久,是我国重要的粮、棉、油和水产基地。伴随着农业开发与工业、城市快速发展,长江流域湿地保护面临一系列问题:围湖造田和城市化导致天然湿地面积减少,湿地功能减弱,水质污染严重,湿地生态环境退化,湿地资源过度和不合理利用,造成生物多样性下降。因此,在长江流域开展湿地生态健康状况研究很有必要。根据长江流域湿地生态系统的特点,基于压力-状态-响应(PSR)模型,建立包含压力、状态、响应3大类共14个指标的生态系统健康评价指标体系。以Globe Land30土地覆盖数据和社会经济统计等数据为基础,结合层次分析法对长江流域2000年和2010年湿地进行了综合评价。研究结果表明:1)从2000年到2010年长江流域湿地生态健康状况略微下降,2000年长江流域平均湿地生态健康指数是0.478,2010年的为0.475;2)2000年和2010年长江流域湿地生态健康指数中游的下游的上游的,湿地生态健康状况较差的区域主要分布在西北部和以重庆、武汉和上海为主的三大经济中心;3)从行政区平均健康水平来看,从2000年到2010年,江西省和福建省的湿地生态健康状况有所好转,而云南省、广西省、贵州省和重庆市受2010年干旱影响,湿地生态健康状况有所下降。     

湖滨湿地氮磷的转化及其归趋研究进展

概述了氮（Ｎ）、磷（Ｐ）两种元素在湖滨湿地迁移的研究．随着富营养化问题日趋严重,湖泊水体可能逐渐由Ｎ、Ｐ的汇转变成向周围湿地输出的源,湖滨植被及土壤微生物可能起着关键作用．开展Ｎ、Ｐ元素在富营养化湖泊水体与湖滨湿地间的迁移及其在湖滨湿地的归趋研究,有助于阐明湖滨湿地对富营养化湖泊的生态效应,为湖滨带湿地优化管理提供参考数据．     

气候变化对洪湖湿地的影响研究

正引言湖泊湿地具有调蓄洪水、保护生物多样性等生态价值,对于调节气候、供水(蓄水)、水产业、航运等具有经济价值。在全球气候变化背景下,区域气温及降水条件等也发生着明显的变化,对湿地水文、生物地球化学过程、水质与水循环、湿地能量平衡与湿地生态功能等产生较大的影响。本项目以长江中游典型湖泊湿地——洪湖为例,通过分析过去50年洪湖湿地气候、水文与生态系统发展变化过程及湿地生态     

扎龙湿地气候变化特征分析

气候是影响湿地生态状况最重要的自然因子.本文分析了自1961～2007年研究区域内对湿地生态状况有重要影响的各气候要素变化趋势.结果表明该区域气候变暖趋势明显.20世纪90年代后湿地处于高温、少雨、蒸发量较大的气候背景之下,由此导致湿地水资源严重不足,进而产生生物多样性下降和湿地退化等现象.     

Heat Flux Apportionment to Heterogeneous Surfaces Using Flux Footprint Analysis

Heat flux data collected from the Baiyangdian Heterogeneous Field Experiment were analyzed using the footprint method. High resolution (25 m) Landsat-5 satellite imaging was used to determine the land cover as one of four surface types: farmland, lake, wetland, or village. Data from two observation sites in September 2005 were used. One site (Wangjiazhai) was characterized by highly heterogeneous surfaces in the central area of the Baiyangdian: lake/wetland. The other site (Xiongxian) was on land with more uniform surface cover. An improved Eulerian analytical flux footprint model was used to determine "source areas" of the heat fluxes measured at towers located at each site from surrounding landscapes of mixed surface types.In relative terms results show that wetland and lake areas generally contributed most to the observed heat flux at Wangjiazhai, while farmland contributed most at Xiongxian. Given the areal distribution of surface type contributions, calculations were made to obtain the magnitudes of the heat flux from lake, wetland and farmland to the total observed flux and apportioned contributions of each surface type to the sensible and latent heat fluxes. Results show that on average the sensible heat flux from wetland and farmland were comparable over the diurnal cycle, while the latent heat flux from farmland was somewhat larger by about 30-50 W m-2 during daytime. The latent and sensible fluxes from the lake source in daytime were about 50 W m-2 and 100 W m-2 less, respectively, than from wetland and farmland. The results are judged reasonable and serve to demonstrate the potential for flux apportionment over heterogeneous surfaces.     

Heat flux apportionment to heterogeneous surfaces using flux footprint analysis

Heat flux data collected from the Baiyangdian Heterogeneous Field Experiment were analyzed using the footprint method. High resolution （25 m） Landsat-5 satellite imaging was used to determine the land cover as one of four surface types： farmland, lake, wetland, or village. Data from two observation sites in September 2005 were used. One site （Wangjiazhai） was characterized by highly heterogeneous surfaces in the central area of the Baiyangdian： lake/wetland. The other site （Xiongxian） was on land with more uniform surface cover. An improved Eulerian analytical flux footprint model was used to determine “source areas” of the heat fluxes measured at towers located at each site from surrounding landscapes of mixed surface types. In relative terms results show that wetland and lake areas generally contributed most to the observed heat flux at Wangjiazhai, while farmland contributed most at Xiongxian. Given the areal distribution of surface type contributions, calculations were made to obtain the magnitudes of the heat flux from lake, wetland and farmland to the total observed flux and apportioned contributions of each surface type to the sensible and latent heat fluxes. Results show that on average the sensible heat flux from wetland and farmland were comparable over the diurnal cycle, while the latent heat flux from farmland was somewhat larger by about 30-50 W m-2 during daytime. The latent and sensible fluxes from the lake source in daytime were about 50 W m-2 and 100 W m-2 less, respectively, than from wetland and farmland. The results are judged reasonable and serve to demonstrate the potential for flux apportionment over heterogeneous surfaces.     

辽河流域生态系统时空格局及服务价值变化研究

以辽宁省境内辽河流域为研究对象,将流域生态系统划分为7类,从全流域、15个子流域、河岸带3个尺度分析了生态系统结构的空间和时间变化,结合生态系统服务价值评估方法,评价了三个尺度下生态系统服务价值及变化。结果表明：全流域生态系统以农田和森林生态系统为主,子流域生态系统结构及时空变化存在较大差异,河岸带生态系统结构与全流域结构差异显著,与全流域生态系统结构相比,河岸带森林生态系统所占成分显著降低,水体与湿地生态系统显著增加。全流域生态系统服务总价值逐渐降低,森林生态系统服务价值最高;子流域内森林生态系统服务价值对子流域服务价值最大;河岸带内水体与湿地生态系统服务价值最大。     

Numerical simulations of wind and temperature structure within an Alpine lake basin, Lake Tekapo, New Zealand

Summary High-resolution numerical model simulations have been used to study the local and mesoscale thermal circulations in an Alpine lake basin. The lake (87km²) is situated in the Southern Alps, New Zealand and is located in a glacially excavated rock basin surrounded by mountain ranges that reach 3000m in height. The mesoscale model used (RAMS) is a three-dimensional non-hydrostatic model with a level 2.5 turbulence closure scheme. The model demonstrates that thermal forcing at local (within the basin) and regional (coast-to-basin inflow) scales drive the observed boundary-layer airflow in the lake basin during clear anticyclonic summertime conditions. The results show that the lake can modify (perturb) both the local and regional wind systems. Following sunrise, local thermal circulations dominate, including a lake breeze component that becomes embedded within the background valley wind system. This results in a more divergent flow in the basin extending across the lake shoreline. However, a closed lake breeze circulation is neither observed nor modelled. Modelling results indicate that in the latter part of the day when the mesoscale (coast-to-basin) inflow occurs, the relatively cold pool of lake air in the basin can cause the intrusion to decouple from the surface. Measured data provide qualitative and quantitative support for the model results.     

Thermal and dynamic characteristics of alpine lake breezes,Lake Tekapo,New Zealand

Thermodynamic characteristics and temporal variation of alpine lake breezes in the eastern Southern Alps are examined. Research was conducted in a large glacially excavated basin dominated by an 87 square kilometre melt-water lake as part of a study of windblown dust dispersion. The surrounding mountain ranges were found to shelter the lake basin from most synoptic winds, thereby allowing local and regional thermally generated circulations to develop to ridge height, approximately 1300m above the surrounding landscape. During favourable synoptic conditions the local lake breeze becomes embedded within the regional valley wind forming an extended lake breeze. Tethersonde flights during these conditions made using a kite based sounding system identified both stable internal (SIBL) and thermal internal boundary layer (TIBL) conditions over the down wind shoreline. Two equations for estimating the height of both boundary-layer types were tested against observations and found to provide good first order predictive estimates of boundary-layer height.     

巢湖流域典型站点的风场特征分析

研究巢湖流域流场特征对于认识该地区热量、水汽交换和水流运动规律具有重要意义。利用2006年合肥、肥东、巢湖、庐江站以及姥山岛自动气象站的风场资料,分析了巢湖流域典型站点的风速和风向变化特征。结果表明,陆面站点年平均风速为2.17m/s,湖面站点风速为2.41m/s。所有站点春夏季风速大于秋冬季,陆上风速具有明显的日变化,白天风速大于夜间,而湖面风速日变化较不显著。陆面站点风向季节变化明显,春夏季以偏南风为主,秋冬季以偏北风为主,春夏季的风向日变化特征较秋冬季明显,湖面站风向没有明显的季节变化。陆面站点不同程度地受到湖陆风的影响,距离湖面较近的站点受到的影响较大。湖面和陆面站点风向差距平与气温差距平的日变化保持一致,表明湖陆温差是影响巢湖流域湖陆风的关键因子。     

基于TM数据的湿地变化分析—以磴口县为例

利用2001、2006、2010年的TM遥感图像,采用目视解译的方法对磴口县湿地面积进行提取,结合气象数据,并对其变化进行分析。结果表明,2000—2010年,磴口县年降水呈现不及30a(1981—2010年)平均值的年份明显偏多,7—8月平均气温逐年上升;除内陆滩涂面积有所减少外,河流水体、湖泊坑塘水体以及湿地植被面积都有不同程度的增加,变化速率分别为2.06%、0.85%和4.65%,以湿地植被面积增加最为迅速。     

柳州新一代天气雷达通风系统的改进措施

通过对1994年8月4日与2004年9月16日若尔盖湿地TM影像1～5波段和7波段数据以及归一化植被指数(INDVI)、归一化水指数(INDWI)、归一化水分指数(INDMI)和改进的归一化水指数(IMNDWI)的分析,选择通道7、4、3合成假彩色图作为若尔盖湿地的目视解译图,确定了湿地的TM影像标志.分析结果表明,第7波段能较好地将沙地与其它地物区分,改进的归一化水指数与归一化植被指数之差是非常有效的水体提取因子.还制定了若尔盖湿地主要地物的自动判识流程.判识结果与目视解译结果非常吻合,1994年比1984年湖泊面积,沼泽湿地面积明显减小,而沙化地面积扩大.     

Evaluation of the Climatic Change Impacts on the Inland Lake – A Case Study of Lake Qinghai, China

A catchment model coupled with a lake thermal model has been used to simulate the lake water balance of Lake Qinghai, a large inland lake on the northeast Qinghai-Tibet Plateau in China. The sensitivity analyses show that changes in precipitation will produce larger changes in runoff than temperature and cloudiness, whereas changes in lake level are equally sensitive to changes in temperature and precipitation. With a doubling of CO₂ in the atmosphere, four GCMs experiments predict warmer and wetter conditions in the Qinghai region than at present. The total runoff in the lake basin and evaporation will, in most cases, increase as conditions become warmer and wetter. The lake level changes would remain uncertain because the effects of an increase in precipitation are countered by the rise of temperature.