呼伦湖湿地干旱评价及生态修复

发布时间：2018-10-18 16:55

【摘要】：在全球气候变暖及不合理的人类活动影响下,干旱事件发生的频率、程度及持续时间都在增强,干旱事件呈现广发、频发态势。气候变暖导致的结果是区域内水循环的变化和径流系数发生相应的变化。湿地作为一个完善的自然生态能力系统,也遭受着越来越严重的干旱影响。呼伦湖湿地位于我国内蒙古自治区东北部,近年来,受气候暖干化和人类不合理利用湿地水资源的影响,周边地区出现了严重的生态危机,湿地来水量减少,去水量增多,水位下降,湖面萎缩,生物多样性减少,湿地生态环境正在急剧恶化。本文以呼伦湖湿地为研究对象,根据呼伦湖湿地水文特征与流域水循环关系,利用湿地水量平衡关系,选取湿地最小生态水位作为干旱指示指标,建立湿地生态干早评价指数对呼伦湖湿地进行生态干旱评价,为湿地保护和湿地干旱评价提供依据。总的来说,本文取得的成果如下：(1)根据呼伦湖湿地水循环系统演变特征,分别对呼伦湖湿地的气象条件、径流量及下垫面条件的变化进行分析。近年来湿地气温升高、降水减少、蒸发呈下降趋势,湿地径流量逐年减少,耕地面积、城镇及居民用地、未利用土地面积逐年增多,林地、草地面积、水域面积逐年减少。(2)在对湿地径流指数的分析的基础上,计算湿地径流干旱指数,通过游程理论对干旱指数进行识别,呼伦湖湿地干旱主要发生在秋季和冬季,平均干旱历时和平均干旱烈度呈增长状态。在进入21世纪以后,干旱频发,持续时间长,干旱烈度大。在水量平衡的基础上,通过对湿地降水量、蒸散发量、出入湖水量等因素的分析处理,构建呼伦湖湿地干旱指数,并对呼伦湖生态干旱指数进行敏感性分析,结果表明湿地干旱指数能够反映湿地历史最干旱情况。在分析湿地生态基流和敏感生态需水的基础上,提出湿地生态保护与修复的措施：主要包括工程措施和非工程措施两部分。其中工程措施主要有生态需水保障措施、水环境保护措施、河湖生境形态修复措施、水生生物保护与修复措施等,非工程措施包括生态补偿、生态调度、生态监控以及技术标准建设等监督管理措施。
[Abstract]:Under the influence of global warming and unreasonable human activities, the frequency, degree and duration of drought events are increasing. The result of climate warming is the change of water cycle and runoff coefficient. Wetland, as a perfect natural ecological capacity system, is also suffering from more and more serious drought. The wetland of Hulun Lake is located in the northeast of Inner Mongolia Autonomous region of China. In recent years, affected by climate warming and unreasonable utilization of wetland water resources, serious ecological crisis has appeared in the surrounding areas, where the amount of water coming from the wetland has decreased and the amount of water removed has increased. The water level drops, the lake surface shrinks, the biodiversity decreases, the wetland ecological environment is deteriorating sharply. According to the relationship between the hydrological characteristics of the wetland and the watershed water cycle, the minimum ecological water level of the wetland is chosen as the indicator of drought, according to the relationship between the hydrological characteristics of the wetland and the watershed water cycle. The evaluation index of wetland ecological dry early was established to evaluate the ecological drought of Hulun Lake wetland, which provided the basis for wetland protection and wetland drought evaluation. In general, the results obtained in this paper are as follows: (1) according to the evolution characteristics of the water circulation system in the Hulun Lake wetland, the changes of meteorological conditions, runoff and underlying surface conditions of the Hulun Lake wetland are analyzed respectively. In recent years, the temperature of wetland increased, precipitation decreased, evaporation decreased, runoff of wetland decreased year by year, cultivated land area, urban and residential land, unused land area increased year by year, woodland and grassland area increased year by year. The water area is decreasing year by year. (2) based on the analysis of wetland runoff index, the drought index of wetland runoff is calculated, and the drought index is identified by running theory. The drought of Hulun Lake wetland mainly occurs in autumn and winter. The average drought duration and average drought intensity increased. After entering the 21 st century, drought occurs frequently and lasts for a long time. On the basis of water balance, through the analysis and treatment of wetland precipitation, evapotranspiration and water flow in and out of the lake, the wetland drought index of Hulun Lake was constructed, and the ecological drought index of Hulun Lake was analyzed. The results show that the wetland drought index can reflect the most arid situation in wetland history. Based on the analysis of wetland ecological basic flow and sensitive ecological water demand, the measures of wetland ecological protection and restoration are put forward, including engineering measures and non-engineering measures. The engineering measures include ecological water demand protection measures, water environment protection measures, river and lake habitat restoration measures, aquatic biological protection and restoration measures, etc. Non-engineering measures include ecological compensation, ecological regulation, etc. Ecological monitoring and technical standards construction and other supervision and management measures.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X171.4

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