【作者】 何春光；

【导师】 盛连喜；

【作者基本信息】 东北师范大学 ， 环境科学， 2008， 博士

【摘要】 20世纪以来,随着人口的急剧增加,全球生物多样性正以空前的速度减少。在“人类只有一个地球”、“保护生物多样性就是保护人类自已!”……的阵阵呼声中,1992年6月在巴西里约热内卢联合国环境与发展大会期间产生了《生物多样性公约》,第一次将保护生物多样性作为全人类的共同使命。但是,全球生物多样性丧失的趋势仍在加剧,如何保护生物多样性,就成为当前人类首要解决的问题之一。生境破坏是生物多样性丧失的首要原因,包括生境消失、生境破碎化、生境污染与生境退化。因此,生境保护的研究成为生物多样性保护的重中之重。地球上的一切生命均离不开水,湿地因水的存在而成为各种生命形式高度聚集的生态系统,它为各种水禽以及其它生物提供了栖息和繁殖的环境,是世界上最富物种多样性的生态系统之一,被称为“物种的基因库”。水禽的多样性是构成湿地生物多样性的重要组成部分,自1971年《湿地公约》签署以来,水禽的生态与保护问题得到世界各国前所未有的重视,水禽的多样性已成为确定国际重要湿地的决定性标准之一。但是,由于人类对湿地资源不合理的开发利用,如围垦、过度放牧、污染等原因,导致湿地环境破坏,人类对水资源的过度开发,导致湿地水文条件恶化,湿地干涸,面积萎缩,严重危及到了湿地中生存的水禽,尤其是大型珍稀濒危物种。近年来,人们对湿地的关键控制要素有了进一步的了解,认识到湿地的水文条件是控制湿地结构和功能的基础,对于湿地的维持和退化的湿地的恢复具有重要作用。目前研究领域关注的焦点是生物以及生物与环境构成的生态系统与水文条件之间的关系,应用方面主要体现在为解决生态需水和水资源管理等实践活动提供科学依据。本研究以中国东北松嫩平原上国际重要湿地——吉林向海国家级自然保护区为研究区,通过多年的野外实地调查和多时相的遥感数据分析,研究向海湿地水禽的多样性保护与湿地水文条件间的关系,为基于水禽栖息地保护的水资源管理提供依据。本研究的实施步骤如下:a野外调查向海湿地水禽的种类及珍稀濒危物种丹顶鹤的繁殖信息,分析水禽的多样性动态与丹顶鹤营巢数量间的关系,确定丹顶鹤的营巢数量为向海湿地水禽多样性的重要指标,并分析丹顶鹤的营巢生境特征; b利用遥感数据分析丹顶鹤营巢生境特征及其与水文条件之间的关系,确定营巢生境保护的关键因子;c利用159幅“图像数据”,研究了向海湿地集水区域面积的长期动态,分析了集水区域面积变化与河流流量、降雨量和蒸发量等因子之间的关系,构建了预测集水区域面积变化的经验模型;d利用构建的经验模型和野外调查资料,讨论了河流水文配置方案以保证丹顶鹤营巢生境所需要的集水区面积;e基于流域综合管理的理念,从霍林河流域尺度上提出了具体的向海湿地丹顶鹤栖息生境及其它水禽多样性保护的措施和方案。具体结果如下:(1)多年野外调查的结果表明:向海湿地水禽的多样性年际间变化幅度较大,对湿地环境的变化反应比较敏感。水禽的多样性变化与珍稀濒危物种丹顶鹤的营巢数量呈较好的正相关(R=0.915),验证了丹顶鹤是湿地生态环境质量“指示物种”的说法。统计数据分析表明:丹顶鹤对营巢生境的选择具有特异性和定向性,即最偏爱的营巢生境为有水的芦苇群落,这种生境不仅可以为丹顶鹤提供巢材和丰富的食物来源,而且是比较好的隐蔽场所,可防止人和其它动物的干扰。如何保护好向海湿地的水生芦苇群落,就成为了保护丹顶鹤及其它水禽生境的关键。(2)利用多时相的遥感数据,分析了野外调查期间向海湿地水生芦苇群落的分布。通过组合波段6和波段7,提出了一个新的指数(水指数WI),用于从遥感影像中识别集水区域。利用向海水库管理局提供的关于向海水库的季节性集水面积变化数据,进一步证实了该指数的可适用性。本研究利用NDVI指数来提取水生芦苇群落区域。NDVI并不能将芦苇从其它物种中区别出来,但芦苇是向海湿地区水中的绝对优势植物种,通过将集水区域与高NDVI值区域图叠加,获取了水生芦苇群落的动态分布图谱,将丹顶鹤的巢位信息与水生芦苇群落的分布图进行叠加,两者吻合的概率达到了82%,说明通过遥感影像获取的水生芦苇群落信息是可信的。(3)水生芦苇群落的面积与集水面积的相关分析表明:向海湿地集水区的面积是指示向海湿地丹顶鹤繁殖生境质量的重要指标,它控制着水生芦苇群落的面积(R=0.996)。借用一种“图像数据”来分析集水区域面积的长期变化。图像数据与遥感影像数据的分析结果比较表明两者的相关系数达到0.957。根据159幅图像数据的分析,发现向海湿地集水区域面积季节性变化很大,在晚夏时面积最大,早春季节最小。1994年前,水域面积变化相对稳定,变化范围为20-60km2;但是1995年后,它变得极不稳定,有时超过100km2,有时甚至无水。这种变化主要是由于全球气候变化及农业灌溉大量耗水的结果。(4)考虑到水文因子的季节性变化,将整个分析过程分为两个阶段:集水面积扩张期(4月到9月)和集水面积收缩期(10月到来年的3月)。第一个时间段的分析表明:9月份的集水面积主要受前6个月内霍林河的流量和向海降雨量的累积量控制,根据回归方法建立了经验方程。利用方程获取的预测值与原始值的相关系数达到0.927。第二个时间段的分析表明:3月份的集水域面积,也即丹顶鹤迁来时的水域面积,主要受单一因子控制,即上一年9月末的水面积。因为冬季霍林河的流量以及向海地区的降雨量都非常小,利用回归建立的经验方程获取了3月份集水域面积的预测值,该预测值与原始值的相关系数达到了0.942。(5)通过比较集水区域面积与丹顶鹤筑巢数量之间的关系,发现早春季节存在丹顶鹤筑巢的临界水域面积。如果3月末的集水域面积在11km2以上,筑巢数量稳定在10巢以上,如果小于这个面积,其数量锐减。根据建立的经验方程,可以推测9月末相应的临界水域面积为16.2km2。根据另外一个经验模型(利用累积流量和累积降雨量预测9月末的集水区面积模型),推导丹顶鹤营巢生境的临界水文条件。为进一步开展向海湿地水文调控提供了科学依据。(6)基于流域综合管理的理念,提出了从霍林河流域尺度保护向海湿地水禽生境具体的措施和技术,包括:开展洪水资源化的技术和方法,促进湿地保护与地方经济协调发展的思路和途径,初步设计了霍林河流域的生态区,并从流域的尺度上提出了保护向海湿地的河流流量标准。如果向海出现极端干旱的情况(4月至9月间的累积降雨量仅为200mm),则为了保证9月末该区临界水域面积所必须的流量应为13m3/s(4月至9月的月平均流量)。考虑到向海地区实际的年降雨量以及霍林河多年月平均流量情况,上游的流量控制在5m3/s即可以保证下游向海地区丹顶鹤及其它水禽的正常繁殖和生存。为了保护丹顶鹤繁殖生境所需的水量,在控制吐列毛都水文站流量达到这一标准的同时,需要规划吐列毛都至向海湿地这一区段的用水规模和强度,使其控制在一定的水平内。更多还原

【Abstract】 The biodiversity on the earth has been decreased greatly with the increasing of global population since the 20th century. This condition is still more serious since the《Convention on Biological Diversity》which was signed in 1992. Therefore, the conservation of biodiversity is becoming an all-important problem which should be solved firstly. Habitat destruction was thought to be the most important reason for biodiversity decreasing, therefore, the study on the habitat conservation will be the most important for the conservation of biodiversity.All the life comes from water, therefore, the wetland becomes the most important ecosystem where all kinds of the life cluster due to the existence of water. Wetland was called the“Gene pool of species”because it can provide the habitat for all the waterfowl. The conservation and ecology of waterfowl has been paid more attention then before since the《Convention on Wetlands of International Importance Especially as Waterfowl Habitat》which was signed in 1971. The diversity of waterfowl has become an important part of wetland biodiversity, and one of the crucial standards which the international important wetland is classified. However, the ecological environment of wetland is deteriorating more serious due to the unwise used wetland resource, e.g. reclamation, over grazing, and pollution, etc. Especially, the over using of water resource for economic development resulted in decreasing of the water quantity in wetland. The dried wetland has threatened the survival of waterfowl, especially those rare and endangered species with big body, which are in the high position of the ecosystem.Aiming at the status of the waterfowl diversity in wetland decreasing greatly, the Xianghai National Nature Reserve, one of the international important wetlands which locates in the Songnen Plain of Northeast China, was selected as the study area for studying the conservation of waterfowl diversity based on the investigation and remote sensing data analysis. The result of this study could serve as scientific instruction for the conservation of waterfowl diversity in Songnen plain and other area of China.The scenario of this research is as follows:①Investigation of the waterfowl species and breeding information of Red-crowned crane, a kind of endangered species which breed in Xianghai wetland. And the nesting number of Red-crowned crane could serve as an important index of the waterfowl diversity, then analyzed the characteristic of the nesting habitat of Red-crowned crane;②finding the dependency of their habitat on the hydrological condition in Xianghai with the analysis of Landsat-TM data;③159 scene of“Quick-look”images were analyzed for studying the long-term dynamic of water area in Xianghai, and then constructing some experiential models for predicting the change of water area;④ Constructing a strategy to get the utilization of water resources in local community together with the conservation of the habitat of the Red-crown cranes and other waterfowl based on the thinking of integrated river basin management.The result of field research showed that the diversity of waterfowl in Xianghai wetland changed greatly among different year, but the one of non-waterfowl species changed not so much. The change of waterfowl diversity has significant positive relationship with the nest number of Red-crowned crane, which proved a common parlance that this species is the“index species”of wetland ecological environment quality. So if we can protect the habitat of Red-crowned crane well, the waterfowl diversity in Xianghai area will be rich. The statistic analysis of the field data showed that the Red-crowned crane selects the reed communities with shallow water as their favorite nesting habitat because it can not only provide the food and nesting material, but also the hiding place from the disturbance of other animal and human. Therefore the protection of reed communities with shallow water is the key for conserving the Red-crowned and other waterfowl.The distribution of“reed communities with shallow water area”was investigated by analyzing twelve scenes of Landsat-TM data for the period of seven years when the field observations were conducted in Xianghai. A new index named Water Index (WI) was proposed in order to identify the water area by using Band-6 and Band-7 data. Its availability was proved for the seasonal variation of the water area of Xianghai Reservoir which the Xianghai Management Bureau reported. On the other hand, NDVI is employed to identify the vegetation in Xianghai. NDVI cannot distinguish reed from other species, but because reed is only one species in the water area in Xianghai, so the“reed communities with shallow water”was successfully identified by overlaying the maps of WI and NDVI. The results agreed very well with the facts that were obtained in the field study in Xianghai.The area of“reed communities in water”is naturally controlled by the variation of the total water area. Then, its long-term change was investigated by utilizing Quick-look image data, which we can download freely through the Internet, while the Landsat-TM data is expensive and we cannot afford to buy many. From the analysis of 159 scenes of Quick-look images, we found that the water area in Xianghai has a large seasonal variation, taking a maximum in late summer and a minimum in early spring. A change of the characteristics around the year of 1994 was also found, before then, the water area had rather stable periodicity between 20 km2 and 60 km2, but after 1995, it became unstable and sometimes there was no water in Xianghai. The change was probably caused by the expansion of global climate change and the propagation of water intake for irrigation from the Huolin River.Considering the seasonal variation of climate in Xianghai, Multiregression analysis was tried by separating the time for analysis into the term of water area expansion (from April to September) and the term of shrink (from October to next March). The first analysis showed that the water area in September is controlled by the cumulative flow rate of Huolin River and the cumulative rainfall in Xianghai area during the six months. An empirical relation among them was found, and the correlation coefficient between the predicted values and the measured was 0.927. On the other hand, the second analysis showed that the water area at the end of March, when Red-crowned cranes visit Xianghai, depends on a single factor that is the water area at the end of last September, because the river flow rate as well as the rainfall in the area are usually very small in winter. The correlation of the measured values with the predicted values by the regression analysis was 0.942.Comparison of the change of water area with the number of cranes’nest that was observed before at the site suggested the existence of“a critical water area”for the cranes’nesting in early spring: If the water area at the end of March is larger than 11 km2, the number of observed nests is stably larger than ten. If it is smaller than the critical value, the number of nest drops sharply. The corresponding water area in September is estimated as 16.2 km2 from the empirical formula that was deduced before. The other empirical formula was constructed from the regression analysis for the water area in September showed that the critical hydrological condition for the nesting habitat of Red-crowned crane, which will give much scientific help for further analysis on the water regulation in Xianghai.A series of approach and technique were supposed for the conservation of waterfowl habitat from the scale of Huolin River based on the thinking of integrated river basin management, which including: wisely use of the flood resource, promoting the harmony of wetland conservation and local economic development, designing the ecoregion in Huolin River roughly, and a level of river flow rate was proposed for conservation of Xianghai wetland from the scale of Huolin River. If the extremely season occurred in Xianghai( the rainfall is only 200mm from April to September), the flow rate of Huolin River necessary to keep the water area of Xianghai to the critical level is 13 m3/s, as a monthly averaged value from April to September. Consideration of the actual rainfall in Xianghai and the monthly averaged river flow rate in Tuliemao, if the rainfall is 250mm from April to September, the river flow rate should be 5m3/s, which will be enough for the conservation of cranes’nesting habitat in Xianghai wetland theoretic. However, we must regulate the intension of water use between the area of Tuliemaodu and Xianghai, which should be controlled at some level.更多还原