鄂尔多斯高原湖泊动态及其生态系统功能研究

发布时间：2018-01-08 08:35

  本文关键词：鄂尔多斯高原湖泊动态及其生态系统功能研究　出处：《内蒙古大学》2016年博士论文　论文类型：学位论文

  更多相关文章： 湖泊动态 气候变化 土地利用 景观格局 浮游植物 熵

【摘要】：湖泊是地球表层各级系统、各级圈层相互作用的联结点,是地球水圈不可缺少的重要环节。湖泊具有调节区域气候、记录区域环境变化、维持区域生态系统平衡和繁衍生物多样性的特殊功能。盐碱湖泊是湖泊发育的后期阶段,约占地球湖泊总数的一半,特别是干旱-半干旱地区,盐碱湖泊数量较多,对维持区域生态系统结构和生产力有着决定性作用。鄂尔多斯地区是我国两大盐碱湖泊群分布区之一,该地区是一敏感、特殊的生态过渡带,是我国干旱-半干旱区相对独立的自然单元。本课题选取鄂尔多斯地区盐碱湖泊群为研究对象,进行了湖泊动态及其驱动因子的研究,研究分析了湖泊生态系统结构和功能,并且应用熵理论分析了盐碱湖泊生态系统的脆弱性。首先运用遥感数据(RS)结合地理信息系统(GIS),研究分析了鄂尔多斯地区湖泊动态变化特征；其次,在生态学、景观生态学、气候学、生物统计等学科理论的具体指导下,分析研究了气候变化和人类活动对湖泊动态变化的影响；第三,研究分析了鄂尔多斯地区典型湖泊水体中的浮游植物物种构成、密度和群落结构,深入分析了浮游植物功能群动态以及与环境因子的相关性；第四,引用熵理论分析评价盐碱湖泊生态系统的脆弱性。研究得出如下结论：1、鄂尔多斯盐碱湖泊群动态变化特征：湖泊面积和数量变化的总趋势是减少的,在研究时间序列范围内,从1980年～2012年,湖泊面积大于1 Km2湖泊数量由83个减少到57个,湖泊消失或干涸共26个,损失率达31.33%；湖泊水域面积由334.52 Km2减少到234 Km2,湖泊面积损失100.52Km2,损失率达30%。从1980年～1995年,湖泊数量由83个增加为93个,新增湖泊数量为10个；湖泊面积由334.52 Km2增加到372.13 Km2,增加面积37.61 Km2。从1995年～2012年,湖泊数量由93个减少到57个,湖泊消失数量为36个；湖泊面积由372.13Km2减少为234 Km2,减少量为38.13 Km2。湖泊这种动态特征是气候变化和人类活动干扰两大因素的共同作用的结果。2、分析湖泊动态的主要驱动因子之一气候驱动因子,研究课题选取了1960-2012年鄂尔多斯地区的气候数据进行统计分析,得到结论为鄂尔多斯区域气候总趋势趋向变暖,研究区域气温动态变化幅度增幅范围在0.45℃/10a～0.6℃/10a之间,明显高于全国平均水平的0.208℃/10a；降水量总体趋势呈减少趋势,在1960s降水量波动较大,从1968年～2012年的时间序列上,降水量的整个趋势的线性拟合递减率值为4.16mm/10a。灰度关联分析,降水量、气温与湖泊面积变化具有较高的关联度值。3、人类活动干扰是湖泊动态变化的主要驱动因子之一,土地是人类生存的基础资源,所以土地利用动态能够充分揭示出人类活动干扰的强度。通过对鄂尔多斯地区土地利用动态的研究,得出结论：在1980-2012年鄂尔多斯地区增加的土地覆盖类型主要为草地、林地、建设用地,增加的数量分别为：1367.03 Km2、424.96 Km2、204.46 Km2,减少的土地覆盖类型为未利用土地和耕地,减少的数量分别为1991.57Km2、156.291Km2;面积变化显著的土地覆盖类型是草地和未利用土地,在33年的时间序列上,草地面积增加了1367.03 Km2,未利用土地类型减少了1991.57Km2。其中湖泊面积呈减少趋势,通过不同时间序列上土地动态度分析,湖泊动态变化主要在1995-2012年时间序列上,动态度为3.3%。4、景观格局分析可以较好地在区域尺度上揭示鄂尔多斯地区湖泊的动态特征。通过景观格局分析得出：鄂尔多斯地区以草地和沙地为主要景观构成,其次为耕地、林地,总体上是以草地和沙地两大类型构成的基质,辅以耕地和林地的交错景观格局,其他景观类型所占比例很小,构成形似补丁状或带状散布于其中。鄂尔多斯地区景观结构主要是草地、沙地、平原区的耕地、盐碱地为主,其景观功能以此结构类型为基础的；其中湖泊景观比例值很小分别为0.0044(1980年)、0.005(1995年)、0.0041(2012年),三期的鄂尔多斯地区湖泊景观破碎度最小值为1.1(1995年),平均斑块面积最大值为0.91Km2(1995年)。5、在区域尺度上研究鄂尔多斯地区盐碱湖泊生态系统,选取了六个典型湖泊,通过分析湖泊水体中的浮游植物群落来揭示湖泊生态系统结构和功能过程。通过对采集水样在实验室镜检,共鉴定出水体中浮游植物种类为5门28属40种,其中蓝藻门8属11种,绿藻门11属16种,硅藻门7属9种,裸藻门1属3种,甲藻门1属1种；浮游植物优势种是广生性种类,六个样湖浮游植物种类分布依次为：浩通音查干淖尔5门20属25种,红碱淖5门19属24种,其和淖尔4门15属16种,察汗淖尔3门8属10种,哈日芒乃淖尔2门3属4种,巴嘎淖尔2门2属3种。湖泊水体pH为浮游植物密度的主要限制因子,湖泊水体盐度是浮游植物物种多样性的主要限制因子。6、研究鄂尔多斯地区盐碱湖泊生态系统结构和功能,选取红碱淖和浩通音查干淖为研究对象,采用野外实验生态调查方法,结合浮游植物功能群和典范对应分析方法,进行了浮游植物群落季节动态分析以及与环境因子的关系。研究结果为其中红碱淖浮游植物种群按照浮游植物功能群划分方法,共划分为14个功能群：x1/x2/w1/TD/C/J/M/G/Wo/MP/H1/P/S2/Tc,季节变化动态为：J/X1/x2/W1/P/TD/C/M(夏季)→G/P/X1/W1/Wo/MP/H1/TD/S2/Tc(秋季)；浩通音查干淖尔浮游植物划分为8个功能群：X1/F/P/D/W1/Wo/J/Tc,其中季节动态为X1/Tc/J/P/W1/F/D(夏季)→X1/Tc/J/P/W1/F/D/Wo(秋季)。红碱淖和浩通音查干淖尔浮游植物功能群主要是受到pH、总离子度(Tds)、电导率(CON)升高的胁迫,其中pH是影响浮游植物功能群分布的主要因子。7、湖泊生态系统是多因素相互作用的复杂系统,系统结构中各组成成分的相互作用是非线性的,其动态是一个由信息流驱动下各组成成分与环境耦合在一起的自组织过程,熵是复杂系统正确分析中的主要理论工具。为了科学地分析盐碱湖泊生态系统状况,所以在评价鄂尔多斯盐碱湖泊生态系统脆弱性中引用熵函数理论分析是科学的,通过构建评价指标体系,运用综合信息熵模型,得到结论为：鄂尔多斯典型湖泊综合信息熵值依次为HT(浩通音查干淖尔)BG(巴嘎淖尔)HJ(红碱淖尔)QH(其和淖尔)HR(哈日芒乃淖尔)=CH(察汗淖尔),即生态系统脆弱性程度的比较顺序。根据关注因子不同,分别作了关注多个因子和不同因子给予不同权重时的综合信息熵分析,结果显示为：当考虑浮游植物和湖泊面积两项指标时,熵值大小顺序为：QHCHHRHTBGHJ, HJ(红碱淖)熵值最大。通过比较鄂尔多斯地区1980年、1995年、2012年土地利用类型结构的信息熵,依次为1980年(2.74)、2012年(2.71)、1995年(2.54),年际之间的熵值差值很小,说明了该地区土地利用多样性程度近33年里是相似的,但是根据信息熵计算其土地利用均匀度为：1980年(0.598)、1995年(0.56)、2012年(0.6),数值较大,说明土地利用类型有较大的波动,人类活动加强了该区域湖泊生态系统脆弱性程度。鄂尔多斯地区盐碱湖泊动态变化主要是气候变化和人类活动干扰的结果,其变化导致湖泊生态系统结构和功能的变化,尤其人类活动干扰增加了湖泊生态系统脆弱性,鉴于湖泊对于该地区生态系统的无可替代的重要性,应加强湖泊生态系统的恢复和保护。通过本研究更加系统地掌握内陆干旱区盐碱湖泊的变化与驱动机制,为干旱-半干旱区内陆盐碱湖泊生态系统理论作出重要补充,加强了物理学、生物学、生态学、遥感、地理信息系统、景观生态学等诸多学科理论在生态学领域的综合应用,为干旱-半干旱区湖泊的科学研究提供了新的思路,以期为干旱——半干旱区生态文明建设提供科学数据支持。
[Abstract]:The lake is at the connection point of the earth surface system, at all levels of layered interaction, is an important part of the earth's hydrosphere indispensable. Lakes have regulating regional climate, regional environmental change records, maintain the special function of regional ecosystem balance and reproduction of biodiversity. Saline lakes is late stage of Lake development, accounting for about half of the total number of lakes on earth especially, in arid and semi arid areas, a large number of saline lakes, plays a decisive role in maintaining the structure and productivity of regional ecological system. Ordos area is the two largest salt lakes of China group distribution area, the area is a sensitive, special ecological transition zone, is a natural element in arid and semi-arid regions of China independently. The selected saline lakes Ordos area as the research object, the dynamics and driving factors of the lake, the lake ecological research and analysis The system structure and function, and the application of entropy theory to analyze the vulnerability of saline lake ecosystem. Firstly, using remote sensing data (RS) combined with geographic information system (GIS), the research analyzed the change characteristics of the dynamic Ordos Lake area; secondly, in ecology, landscape ecology, climatology, biological statistics and other discipline specific guidance theory. And the effects of climate change and human activities on the dynamic change of Lake; third, research and analysis of the typical water in Lake phytoplankton species Erdos area, density and community structure, in-depth analysis of the phytoplankton functional groups and correlation with environmental factors; fourth, citation analysis of vulnerability assessment of salt lake ecosystem entropy theory. The main conclusions are as follows: 1, Erdos saline lakes dynamic characteristics: the total trend of change of Lake area and the number of The potential is reduced, in the study of time series range from 1980 to 2012, the lake area is greater than the number of 1 Km2 Lake decreased from 83 to 57, a total of 26 lakes disappeared or dry, the loss rate of 31.33%; lake water area decreased from 334.52 Km2 to 234 Km2, the lake area loss of 100.52Km2, loss rate 30%. from 1980 to 1995, the number of lakes increased from 83 to 93, the number of 10 new lake; Lake area increased from 334.52 Km2 to 372.13 Km2, increase the area of 37.61 Km2. from 1995 to 2012, the number of lakes was reduced from 93 to 57, the number of 36 lakes disappeared; the lake area by 372.13Km2 reduced to 234 Km2, reduce the amount of 38.13 Km2. this is Lake dynamic characteristics of climate change and human activities interfere with the interaction of the two factors the results of.2 analysis, one of the main driving factors of climate of Lake dynamic driving factors, research topic selection Take the Erdos area 1960-2012 climate data for statistical analysis, the conclusions for the general trend of warming trend Erdos regional climate research, the regional temperature change amplitude increases in the range of 0.45 DEG /10a to 0.6 DEG /10a, higher than the national average of 0.208 DEG /10a; the overall trend of precipitation decreased in 1960s precipitation fluctuate from time series from 1968 to 2012, the linear trend of precipitation decline analysis, 4.16mm/10a. gray correlation ratio of precipitation, air temperature and Lake area change has high correlation value.3, human disturbance is a major driving factor of dynamic change of lake, land is the basic resource of human to survive, so the land use dynamic can reveal the human disturbance intensity. By using the dynamic study of Ordos land area Conclusion: the increase in Erdos, 1980-2012 years of land cover types mainly grassland, forest land, construction land, increase the number of which was 1367.03 Km2424.96 Km2204.46 Km2, reduction of land cover types for unused land and arable land, reduce the number of 1991.57Km2156.291Km2 respectively; the area change of land cover types and grassland is significant unused land, in the 33 year time series, the grassland area increased by 1367.03 Km2, unused land types decreased 1991.57Km2. the lake area decreased by land dynamic degree analysis in different time sequences, dynamic change of lake mainly in 1995-2012 time series, the dynamic degree of 3.3%.4, the analysis of landscape pattern dynamic characteristics can better reveal the Ordos Lake area on a regional scale. Through landscape pattern analysis: in the Ordos Region Consisting of grass and sand as the main landscape, followed by farmland, woodland, is on the whole matrix formed by the two types of grassland and sandy land, cultivated land and woodland with staggered landscape pattern and other landscape types in the proportion is very small, the shape of patches or bands formed in its spread. The landscape structure is mainly Ordos area the grass, sand, plain area of arable land, saline land, the landscape function based on this structure type; the lake landscape is very small proportion were 0.0044 (1980), 0.005 (1995), 0.0041 (2012), broken Erdos stage three lake landscape area of the minimum value is 1.1 (1995). The average patch area maximum of 0.91Km2 (1995).5, study on saline lake ecosystem Erdos area on the regional scale, selected six typical lakes, to reveal the lake through the analysis of the phytoplankton community in lake water body 娉婄敓鎬佺郴缁熺粨鏋勫拰鍔熻兘杩囩▼.閫氳繃瀵归噰闆嗘按鏍峰湪瀹為獙瀹ら暅妫，

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