中国科学院水利部水土保持研究所机构知识库

本文以位于黄土丘陵区的韭园沟流域为典型研究区，基于1968年、2004年和2018年三期遥感影像，以沟沿线为界提取了研究区沟沿线，进而将研究区分为沟间地和沟谷地两个地貌单元；同时提取了相同时相的土地利用、植被覆盖度和治理措施数据，作为侵蚀沟变化的背景和影响因子；在此基础上，对近50年尺度黄土丘陵沟壑区侵蚀沟（切沟及更大侵蚀沟）时空变化特征进行了分析，利用地理探测器对的影响因素进行了量化分析，最后对侵蚀沟稳定性进行了评价。主要研究结果如下：

（1）基于高分遥感影像对沟沿线的解译结果，与实际地貌特征较为吻合，结合土地利用所、水保措施和植被覆盖度信息，可用于分析侵蚀沟时空动态变化。

（2）50年来研究区侵蚀沟一直在变化，但变化速度在减缓。1968—2004年侵蚀沟沟壁侧蚀和沟头溯源侵蚀都广泛存在，全区平均前进距离56.84m /(km²·a)，2005—2018年，侧蚀相对减弱，主要侵蚀形式以较小的沟头侵蚀进行，全区平均前进距离30.17m/(km²·a)，侵蚀沟变化速率明显减缓。使用5m分辨率非同源DEM数据分析下切侵蚀不能满足精度要求，对于沟道下切侵蚀的研究需要使用更高精度的同源DEM数据。

（3）侵蚀沟的动态变化，研究期的前期（1968年—2004年）主要受到土地利用和植被覆盖度变化的影响，耕地的持续减少、植被覆盖度的快速增加，是对侵蚀沟变化减缓的主要因素；研究期的后期（2005年—2018年），工程措施增加和植被覆盖度持续改善，共同影响了侵蚀沟的变化。LS因子在单因素分析中对侵蚀沟动态变化的影响作用较弱，但在满足一定土地利用方式变化的条件下对侵蚀沟动态变化的解释能力明显增强。

（4）侵蚀沟稳定性评价表明，近50年来侵蚀沟密度增加速率变缓，1968—2004年和2005—2018年两个时段侵蚀沟密度增值分别主要分布在0.1—0.2km/(km²·a)和0—0.1km/(km²·a)。利用土地利用、汇水区域面积、水土保持工程措施等对侵蚀沟稳定性的评价表明，1968—2004年，次不稳定区域面积最大，其次为基本稳定区域；2005—2018年，侵蚀沟表现为稳定和基本稳定，次不稳定区域面积明显减少，不稳定区域呈现集中分布的特点。

受到受DEM数据垂直精度的限制，沟底下切的分析基本没有展开；受到遥感影像数据源和数据配准等限制，侵蚀沟变化分析的时间点偏少。今后，将强调野外实测数据与遥感数据的结合，从沟头前进、沟壁扩张和沟底下切等方面对侵蚀沟的变化进行深入分析。

Based on the three remote sensing images of 1968, 2004 and 2018, the study area was divided into two geomorphic units: intergully land and gully land. Meanwhile, the data of land use, fraction of vegetation cover and engineering measure of soil and water conservation were extracted as the backside of erosion gully change. On this basis, the spatial and temporal characteristics of erosion gullies (gullies and larger channels) in the Loess Hilly and gully region in recent 50 years are analyzed, and the influencing factors are quantitatively analyzed by using geographic detectors. Finally, the stability of erosion gullies is evaluated. The main results are as follows:

(1) The interpretation results of the shoulder-line based on high-resolution remote sensing images are in good agreement with the actual geomorphological characteristics. Combined with the information of land use, water conservation measures and fraction of vegetation cover, it can be used to analyze the spatial and temporal dynamic changes of erosion gully.

(2) Erosion gullies in the study area have been changing for 50 years, but the change rate is slowing down. From 1968 to 2004, the erosion gully lateral erosion and headward erosion were widespread. The average advance distance of the whole area was 56.84 m/(km².a). From 2005 to 2018, the erosion was relatively weakened. The main erosion forms were headward erosion. The average advance distance of the whole area was 30.17 m/(km².a), and the change rate of erosion gully was significantly slowed down. Downward erosion analysis with 5m resolution non-homologous DEM can not meet the accuracy requirement, so it is necessary to use more accurate homologous DEM data for downward erosion research.

(3) The dynamic change of erosion gully is mainly affected by the change of land use and vegetation coverage in the early stage of the study period (1968-2004). The continuous decrease of cultivated land and the rapid increase of fraction of vegetation are the main factors to slow down the change of erosion gully. In the later stage of the study period (2005-2018), the increase of engineering measure of soil and water conservation and the continuous improvement of fraction of vegetation have a common impact. LS factor has a weak influence on the dynamic change of erosion gully in single factor analysis, but its explanatory ability to the dynamic change of erosion gully is obviously enhanced under the condition of satisfying certain land use change.

(4) Evaluating the stability of erosion gully shows that the increasing rate of erosion gully density has slowed down in the past 50 years. The increase of erosion gully density in 1968-2004 and 2005-2018 is mainly distributed in 0.1-0.2 km/(km².a) and 0-0.1 km/(km².a), respectively. The evaluation of erosion gully stability by land use, catchment area and engineering measure of soil and water conservation shows that from 1968 to 2004, the area of sub-unstable region is the largest, followed by the basic stable region; from 2005 to 2018, erosion gully is stable and basically stable, the area of sub-unstable region is obviously reduced, and the unstable region is characterized by centralized distribution.

第一章 绪论.... 1

1.1 选题背景及意义... 1

1.1.1 选题背景... 1

1.1.2 选题意义... 2

1.2 国内外研究现状... 2

1.2.1 侵蚀沟分类研究... 2

1.2.2 沟沿线提取... 3

1.2.3 侵蚀沟调查与监测... 4

1.2.4 侵蚀沟变化影响因素... 4

1.2.5 侵蚀沟稳定性评价... 5

1.2.6 地理探测器在地学研究中的应用... 6

1.3 存在的问题和不足... 7

1.4 论文结构... 7

第二章 研究内容和方法.... 11

2.1 研究区概况... 11

2.2 研究目标及内容... 12

2.2.1 研究目标... 12

2.2.2 研究内容... 12

2.3 数据来源... 13

2.3.1 遥感影像数据... 14

2.3.2 地形数据... 16

2.3.3 其他数据... 16

2.4 研究方法... 16

2.4.1 遥感影像的配准... 16

2.4.2 侵蚀沟形态要素提取及定量描述... 18

2.4.3 土地利用方式及水土保持工程措施提取... 19

2.4.4 植被覆盖度的提取... 20

2.4.5 侵蚀沟稳定性影响因素... 21

2.4.6 微型汇水区域提取及侵蚀沟密度增量计算... 22

2.5 技术路线... 23

第三章 黄土丘陵沟壑区侵蚀沟时空变化.... 25

3.1 侵蚀沟形态特征... 25

3.1.1沟沿线准确性... 25

3.1.2 沟沿线水平分布特征... 27

3.1.3 地形指标分布特征... 29

3.2 侵蚀沟土地利用、水保措施和植被覆盖度变化... 31

3.2.1土地利用和结构变化... 31

3.2.2水土保持工程措施和结构变化... 36

3.2.3植被覆盖度空间分布及变化... 38

3.3 侵蚀沟的动态变化特征... 40

3.3.1 侵蚀沟动态变化量化指标... 41

3.3.2 侵蚀沟动态变化水平变化特征... 43

3.3.3侵蚀沟动态变化垂直变化特征... 44

3.4 小节... 44

第四章 黄土丘陵沟壑区侵蚀沟动态变化影响因素分析.... 47

4.1 侵蚀沟动态变化主导影响因素... 48

4.2 影响因素的交互作用... 52

4.3 小结... 54

第五章 黄土丘陵沟壑区侵蚀沟稳定性评价.... 57

5.1 年均侵蚀沟密度增量的提取与分析... 57

5.2 侵蚀沟稳定性分级评价... 59

5.3 小节... 62

第六章 结论和展望.... 65

6.1 主要结论... 65

6.2 创新点... 65

6.3 问题与展望... 67

参考文献... 69

致  谢... 73

作者简历及攻读学位期间发表的学术论文与研究成果... 75