东北黑土区典型流域融雪期切沟发育特征及成因分析

发布时间：2018-04-14 19:15

本文选题：东北黑土区 + 融雪期　；参考：《沈阳农业大学》2017年硕士论文

【摘要】：中国东北黑土区位于高纬度寒冷地区,属于季节性积雪区,不仅夏季暴雨导致侵蚀比较严重,而且冬春季土壤冻融作用严重,部分地区冻融作用同融雪径流等外营力所造成的土壤侵蚀已不亚于暴雨造成的土壤侵蚀强度,沟蚀为其主要土壤侵蚀形式之一。切沟作为沟蚀主要形式之一,是泥沙主要来源,因此本研究对该区典型流域融雪期切沟发育特征与成因展开研究。研究以暗棕壤为主的五一流域、黑土为主的光荣流域、白浆土为主的吉兴流域为研究对象,运用Differential GlobalPositioning System(DGPS)在每年5月、10月对各流域选取典型切沟进行观测,结合GIS软件空间分析功能,通过10月与翌年5月切沟参数对比,获取其融雪期切沟长度、面积、体积等参数,探究其发育特征,在此基础上以光荣流域为研究区,运用断面法将完整切沟以5m为间隔划分成若干分段切沟,提取各分段切沟宽度、深度、面积、体积等指标,探究其沿程发育特征。然后通过采集同时期积雪获取积融雪特征,查询气象局官网和地理空间数据云获取降水及地形特征,野外调查获取土壤、植被、人类活动特征,收集典型流域对应省(自治区)全国第一次水利普查侵蚀沟调查数据和人类活动强度指标,定量分析降水、地形、土壤、植被、人类活动等对切沟发育影响。研究通过同一流域降雨期和融雪期切沟发育特征对比,定量分析冻融作用对融雪期切沟发育的影响,同时对人类活动进行定量计算,研究结果表明:(1)典型流域融雪期切沟发育具有明显的地域分异性和年际差异性,地域分异性表现为:以暗棕壤为主的五一流域发育速度最快,切沟长度发育为14.23 m/a,面积发育为147.62 m2/a,体积发育336.28 m3/a。以黑土为主的光荣流域次之,长度发育为3.37 m/a,面积发育82.19 m2/a,体积发育133.51 m3/a。以白浆土为主的吉兴流域最慢,长度、面积、体积发育值分别为1.94 m/a、54.6 m2/a、18.71 m3/a;典型流域切沟发育特征呈现为从西北至东南,从暗棕壤到白浆土,切沟发育速率逐渐减小的趋势。年际差异性表现为:暗棕壤为主的五一流域年际差异性最明显,黑土区为主光荣流域次之,白浆土为主的吉兴流域最弱。(2)融雪期沟宽沿程发育特征呈现分异性,沟头至中部发育比较活跃,中部至沟尾发育相对缓慢。光荣流域G1沿程深度发育速率和面积发育速率显著负相关,(p0.05,r=-0.500),与体积发育速率正相关(p0.01,r=0.408),切沟沿程宽度发育和面积发育显著正相关(p0.05,r=0.572),G1发育以沟岸扩张为主,横断面成"V"字型。光荣流域G2沿程宽度发育速率和面积发育速率显著正相关,(p0.05,r=0.412),与体积发育也显著正相关(p0.05,r=0.673),G2发育也以沟岸扩张为主,切沟横断面成"U"字型。这说明融雪期以沟岸扩张为主,侵蚀物质多在沟道堆积,可能是黑土区切沟发育的一种主要模式。(3)坡长、集水区面积、地形因子(LS)等地形特征和人为因素是影响融雪期切沟发育地域分异性的关键原因。切沟长度发育速率与坡长、集水区面积和地形因子均显著相关(r1=0.761,r2=0,634,r3=0.779,p0.05);人类活动与单位面积切沟发育数量显著正相关(r=0.937,p0.05)。降水、冻融作用是影响切沟发育年际差异性关键原因。其中,降水特征是影响五一流域切沟发育年际差异性关键因素,冻融作用为影响光荣流域切沟发育年际差异性关键因素,冻融作用至少使光荣流域切沟沟头后退0.58-5.5 m/a。
[Abstract]:Chinese black soil region of Northeast China located in high latitude and cold regions, which belongs to the seasonal snow areas, not only lead to serious erosion of heavy rainfall in summer, and in winter and spring soil freezing and thawing seriously, soil erosion caused by external forces such as snowmelt runoff with parts of freezing and thawing is less than the intensity of soil erosion caused by rainfall, gully erosion is the main one of the forms of soil erosion gully. As one of the main forms of gully erosion, sediment is the main source, so the research on the typical watershed in gully region of the snowmelt period characteristics and causes of developmental research. A study of five watershed with mainly dark brown, black oriented glory basin, white pulp soil mainly Ji Xing basin as a study the object, using Differential GlobalPositioning System (DGPS) in October May each year, the valley of the typical gully were observed, with the spatial analysis function of GIS software, through October and May next year Comparing the parameters of gully, obtain the snowmelt gully length, area, volume and other parameters, explore its development characteristics, on the basis of the glorious basin as the study area, using cross section method will complete gully with 5m interval is divided into several sections of gully gully, extraction segment width, depth, area and volume other indicators, explore its development features along the way. And then through the acquisition at the same time the snow gets snow melt characteristics, Meteorological Bureau official website and query spatial data acquisition of cloud precipitation and terrain features, field investigation to obtain soil, vegetation, human activities, collect the typical watershed in the corresponding province (autonomous region) the first national census for water erosion gully investigation data and human activity intensity index, quantitative analysis of precipitation, topography, soil, vegetation, human activities on the impact of gully development. Through the study period period of rainfall and snowmelt same watershed gully development characteristics comparison, quantitative analysis Effects of freezing and thawing ditch on the development of snowmelt, and human activities were quantitatively calculated, the results show that: (1) a typical basin snowmelt gully development has obvious regional differentiation and interannual differences, regional differentiation performance: five a watershed with dark brown soil mainly develop most quickly, gully length growth is 14.23 m/a, the development area is 147.62 m2/a, the volume of 336.28 m3/a. in the development of black oriented glorious Valley, the growth of length is 3.37 m/a, the development area of 82.19 m2/a, volume 133.51 m3/a. in development of albic soil mainly Ji Xing River Basin is the slowest, length, area, volume and development value were 1.94 m/a, 54.6 m2/a, 18.71 m3/a; typical watershed gully development characteristics from the northwest to the southeast, from dark brown to white pulp soil, gully development rate gradually decreased. Differences in annual performance: dark brown 51 basin mainly annual The most obvious difference, the black soil region mainly glorious Valley, white pulp soil mainly Ji Xing basin was the weakest. (2) the snowmelt period along the groove width development characteristics are difference, gully head to middle development more active, central to development is relatively slow. The glorious Gou Wei basin G1 along the depth and area of growth rate the developmental rate of significant negative correlation (P0.05, r=-0.500), and the volume growth rate is positive correlation (P0.01, r=0.408), cutting width and area development process along the development of significant positive correlation (P0.05, r=0.572), G1 development to ditch bank expansion, cross section of a "V" shape. The glorious basin G2 along the width of growth rate and the area growth rate was positively correlated (P0.05, r=0.412), and the volume of development is also significant positive correlation (P0.05, r=0.673), G2 development to ditch bank expansion, gully section "U" font. This shows that the snowmelt period to ditch bank expansion, erosion material accumulation in the channel, may Is a main mode of cutting soil area of gully development. (3) the length of slope, watershed area, terrain factor (LS) and other topographic features and human factors is the key reason of snowmelt gully development regional differentiation. Gully length growth rate and length of slope, watershed area and topographic factors were significantly related (r1=0.761, r2=0634, r3=0.779, P0.05); human activities and unit area of gully is positively related to the number of development (r=0.937, P0.05). The precipitation, freezing and thawing effect of gully development differences in annual key reasons. Among them, the characteristics of precipitation is 51 flow gully development domain key interannual difference factors, freezing and thawing to influence the development of gully watershed glorious key interannual difference factors, freezing and thawing at least a glorious Valley gully head back 0.58-5.5 m/a.

【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S157.1

【相似文献】