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1.
东北典型黑土区侵蚀沟形态及分布特征   总被引:6,自引:3,他引:6  
姜芸  王军  张莉 《农业工程学报》2020,36(7):157-165
东北黑土区是中国最重要的粮食生产基地之一,同时也是中国四大水蚀区之一,其中沟道侵蚀是水蚀发生的主要形式,掌握东北黑土区沟道侵蚀的基本情况,剖析其形态及分布特征,对于分析东北黑土区沟道侵蚀的成因及水土流失治理至关重要。该研究以典型黑土区嫩江县为研究区域,利用航空遥感影像及1∶5万DEM对区域内侵蚀沟进行普查统计,并分析侵蚀沟的沟宽、沟长、纵比降等形态特征,以及海拔、坡度、坡向等地形因素对侵蚀沟分布的影响,为黑土区侵蚀沟的治理提供理论依据。研究结果表明:1)沟道侵蚀主要分布在丘陵区,沟道类型以切沟为主,冲沟影响面积仅次于切沟,研究区以小于500 m的侵蚀沟为主,数量及面积分别占总数的96.67%、61.99%;2)侵蚀沟的沟宽与沟长为正相关,纵比降与沟宽、沟长为负相关;3)坡向对各类型侵蚀沟的分布影响较小,坡度对侵蚀沟的分布有一定影响,细沟和浅沟主要分布在2~6°和6~15°的坡面上,而切沟和冲沟则主要分布在0~2°、2~6°的坡面上,90%以上的细沟和浅沟、80%以上的切沟、冲沟发生在耕地上;4)嫩江县冲沟地形阈值模型拟合表明嫩江县冲沟发生的临界坡度较小,较小的坡度就能对坡面形成冲刷,出现冲沟的发生发育,而模型中主导径流过程的参数数值较小,表明嫩江县冲沟的产生可能受到地下过程的影响。  相似文献   

2.
为加快黑土区侵蚀沟治理,以辽宁省黑土区为研究对象,依据区域自然、社会经济及侵蚀沟发展状况,分析确定了黑土区侵蚀沟防治方略,并在辽宁省水土保持区划的基础上,依据总体的区域特征、侵蚀沟现状及水土保持需求,提出了黑土区侵蚀沟防治的总体布局,旨在为全省黑土区侵蚀沟防治体系的构建奠定基础。  相似文献   

3.
东北黑土区土壤侵蚀现状与演变趋势   总被引:17,自引:0,他引:17  
通过分析东北黑土区水土流失面积和强度、侵蚀沟的数量和密度、黑土层厚度和有机质含量以及河流输沙量和含沙量的变化,对黑土区土壤侵蚀的现状和发展演变进行了全面系统的研究。结果显示,东北黑土区水土流失仍在发展之中,侵蚀面积不断扩大,但增加速度减缓,侵蚀强度在增加,黑土层不断变薄,以面蚀为主;侵蚀沟的数量在增加,沟道继续扩展,向大沟方向发展;土壤养分下降;河流泥沙缓慢增加。协调粮食生产与水土保持的关系是今后防治黑土区土壤侵蚀的关键。  相似文献   

4.
东北黑土区沟蚀研究与防治   总被引:3,自引:1,他引:2  
沟蚀是导致我国东北黑土区土地退化的重要因素。阐述了开展东北黑土区沟蚀研究的意义,分析了东北黑土区沟蚀研究与国外和国内黄土高原沟蚀研究的差距,进而介绍了近年来对东北黑土区5个典型流域侵蚀沟发生发展规律研究的初步成果,包括沟蚀的分布、形态特征和侵蚀沟迅速发育的原因,提出了东北黑土区沟蚀的防治对策,肯定了东北黑土区水土流失综合防治试点工程的防治效果。  相似文献   

5.
东北黑土区的侵蚀沟治理措施与模式   总被引:2,自引:1,他引:1  
[目的]面向东北黑土区侵蚀沟治理专项国家重大工程的科技需求,总结凝练出东北黑土区侵蚀沟治理措施与模式,为东北黑土区侵蚀沟治理提供技术支撑。[方法]采用天地一体化现场调查的方法,对不同时期已开展治理的侵蚀沟详查,获得侵蚀沟形态特征参数、影像资料及空间信息;调查侵蚀沟治理模式与措施种类以及实施后的水保效果。[结果]东北黑土区侵蚀沟治理主要有柳跌水和浆砌石跌水等沟头防护、柳编水道和石笼谷坊等沟底稳固、乔灌混交沟岸防护3大类措施组成;总结已有治沟措施的不足并提出了完善方案;治理模式可归为工程为主植物为辅,植物为主工程为辅,植物和填埋复垦4大类别。[结论]目前东北黑土区侵蚀沟治理已构建了成熟的治理模式与多样化的治理措施,实施情况总体良好,但仍存在治理模式选择与措施组装的不合理现象,应注意施工质量管控和加强后期管护。  相似文献   

6.
辽宁省东北黑土区侵蚀沟专项治理工程开展以来,通过各项治理措施的实施,为项目区带来系列的社会、经济、生态效益。以铁岭县李千户镇项目区为例,阐述侵蚀沟道治理采取的工程措施、植物措施等,为辽宁省其他东北黑土区乃至全省侵蚀沟治理提供技术支撑与借鉴。  相似文献   

7.
辽宁省划分为东北黑土区和北方土石山区2个一级区,以土石山区为主,涉及11个市,72个县(市、区),总面积达93 869万km~2,约占全省土地面积63.40%。沟道侵蚀是该区水土流失的集中体现和严重区域,经统计,辽宁土石山区共有侵蚀沟道74 124条。分析侵蚀沟特点、成因及危害,对开展该区域的侵蚀沟道综合治理工程、指导其水土保持工作具有重要作用。  相似文献   

8.
在近些年来国家开展的黑土区侵蚀沟治理情况实地调研的基础上,结合吉林省侵蚀沟治理技术的研究成果,根据目前吉林省侵蚀沟治理现状,即国家投资强度低,侵蚀沟道以外汇水区治理困难(农民不愿因治理而占用土地)或根本不允许治理,沟坡兼治的技术路线得不到有效贯彻,甚至只能对侵蚀沟道本身进行治理的实际情况,提出了在现有技术和相关标准情况下各类型侵蚀沟汇水区域、沟头、沟岸、沟坡和沟底治理措施的配置体系,可为决策部门及设计部门开展侵蚀沟治理规划设计提供参考。  相似文献   

9.
正为落实《全国水土保持规划(2015—2030年)》,2016年水利部启动了《东北黑土区侵蚀沟治理专项规划(2016—2030年》编制工作。松辽委成立了编制工作领导小组,组织东北黑土区有关省区,经过深入调查研究、广泛征求意见、反复论证咨询,初步完成了专项规划编制工作。专项规划涉及东北四省区103万km~2,分析了东北黑土区侵蚀沟发展及其防治现状,系统总结了侵蚀沟治理的成效和经验,确定了  相似文献   

10.
东北黑土区侵蚀沟分级初探   总被引:4,自引:1,他引:3  
水利部2016年组织编制了《东北黑土区侵蚀沟治理专项规划(2016—2030年)》,国家农业综合开发东北黑土区侵蚀沟综合治理工程也已启动实施。为便于侵蚀沟综合治理模式和投资标准的确定,以第一次全国水利普查东北黑土区侵蚀沟普查数据和《东北黑土区水土保持措施效益评估及防治技术》课题调查数据为依据,对侵蚀沟的长度、宽度、深度、面积等参数进行相关性综合分析后,选择面积作为分级指标,将东北黑土区发展型侵蚀沟按照大型(占地面积≥1.4 hm~2)、中型(占地面积0.3~1.4 hm~2)、小型(占地面积≤0.3 hm~2)进行了分级。  相似文献   

11.
切沟侵蚀是黄土高原丘陵沟壑区水土流失的重要形式之一,然而极端暴雨条件下不同土地利用类型坡面切沟侵蚀研究还鲜见报道。该研究以陕北2017年"7·26"特大暴雨为例,研究了岔巴沟流域3种土地利用类型(农地、休闲地和撂荒地)坡面切沟发育形态特征及体积估算模型。结果表明:1)农地、休闲地和撂荒地切沟长度分布在20 m内的占比分别为55.6%、34.8%和44.8%;农地切沟平均深度为110 cm,分别比休闲地和撂荒地高18.3%、19.2%;农地和休闲地切沟平均宽深比分别为0.87和0.84,横断面呈"宽-浅型",而撂荒地切沟呈"方型"(宽深比1.01)。2)撂荒地切沟侵蚀体积分别比农地和休闲地减少47.8%和28.3%,表明植被恢复有效地削弱了极端暴雨作用下的切沟侵蚀。3)农地切沟不同坡段侵蚀体积由高到低为下坡、上坡、中坡,而休闲地和撂荒地切沟侵蚀体积沿坡长方向呈递增趋势;3种土地利用类型切沟在上坡段的沟岸拓宽速率大于下切速率,中下坡则相反。4)农地、休闲地和撂荒地切沟侵蚀体积均与切沟长度、横断面面积呈极显著幂函数关系(P<0.001),横断面面积是切沟体积估算更为有效的参数。研究结果可为黄土高原丘陵沟壑区不同土地利用类型坡面切沟侵蚀体积估算及其防治提供重要依据。  相似文献   

12.
卢旺达共和国山地丘陵区土壤侵蚀调查报告   总被引:1,自引:1,他引:0  
[目的]在卢旺达山地丘陵区开展土壤侵蚀调查,分析该区土壤侵蚀特征及成因,为尼罗河上游山地丘陵区土壤侵蚀预报和水土流失防治提供科学依据。[方法]在卢旺达布设4条调查路线并选择调查点,于2019年10月17—22日对调查点土壤侵蚀特征、成因及水土保持措施等进行了调查。[结果]卢旺达多山地且以农牧业为主,土壤侵蚀主要发生在坡耕地、损毁林地、建设用地等。坡耕地以片蚀和细沟侵蚀为主。损毁林地以片蚀和细沟侵蚀为主,部分出现沟蚀;当裸露地表形成草地或幼林后均较少发生土壤侵蚀。公路边坡、开挖边坡、土路路面及边坡等在降雨及径流的作用下产生沟蚀,部分路段偶有勤侵蚀发生。梯田是该国最主要的水土保持措施,具有较好的生态和经济效益。[结论]卢旺达土壤侵蚀主要以水力侵蚀为主,重力侵蚀次之。不合理的开垦坡地、毁林,加之多山的地形,导致侵蚀较为严重,威胁当地的生态安全及粮食安全。该区缺乏水土流失监测资料,需要重视水土保持基础理论研究,加强水土流失基础数据的监测和采集,同时需要加强其水土保持措施及土地管理工作,保障卢旺达农业的可持续绿色发展。  相似文献   

13.
Gully erosion: Impacts, factors and control   总被引:21,自引:1,他引:21  
C. Valentin  J. Poesen  Yong Li 《CATENA》2005,63(2-3):132
Gully erosion attracts increasing attention from scientists as reflected by two recent international meetings [Poesen and Valentin (Eds.), Catena 50 (2–4), 87–564; Li et al., 2004. Gully Erosion Under Global Change. Sichuan Science Technology Press, Chengu, China, 354 pp.]. This growing interest is associated with the increasing concern over off-site impacts caused by soil erosion at larger spatial scales than the cultivated plots. The objective of this paper is to review recent studies on impacts, factors and control of gully erosion and update the review on ‘gully erosion and environmental change: importance and research needs’ [Poesen et al., 2003. Catena 50 (2–4), 91–134.]. For the farmers, the development of gullies leads to a loss of crop yields and available land as well as an increase of workload (i.e. labour necessary to cultivate the land). Gullies can also change the mosaic patterns between fallow and cultivated fields, enhancing hillslope erosion in a feedback loop. In addition, gullies tend to enhance drainage and accelerate aridification processes in the semi-arid zones. Fingerprinting the origin of sediments within catchments to determine the relative contributions of potential sediment sources has become essential to identify sources of potential pollution and to develop management strategies to combat soil erosion. In this respect, tracers such as carbon, nitrogen, the nuclear bomb-derived radionuclide 137 Cs, magnetics and the strontium isotopic ratio are increasingly used to fingerprint sediment. Recent studies conducted in Australia, China, Ethiopia and USA showed that the major part of the sediment in reservoirs might have come from gully erosion.Gullies not only occur in marly badlands and mountainous or hilly regions but also more globally in soils subjected to soil crusting such as loess (European belt, Chinese Loess Plateau, North America) and sandy soils (Sahelian zone, north-east Thailand) or in soils prone to piping and tunnelling such as dispersive soils. Most of the time, the gullying processes are triggered by inappropriate cultivation and irrigation systems, overgrazing, log haulage tracks, road building and urbanization. As exemplified by recent examples from all over the world, land use change is expected to have a greater impact on gully erosion than climate change. Yet, reconstructions of historical causes of gully erosion, using high-resolution stratigraphy, archaeological dating of pottery and 14C dating of wood and charcoal, show that the main gully erosion periods identified in Europe correspond to a combination not only of deforestation and overuse of the land but also to periods with high frequency of extreme rainfall events.Many techniques have proved to be effective for gully prevention and control, including vegetation cover, zero or reduced tillage, stone bunds, exclosures, terracing and check dams. However, these techniques are rarely adopted by farmers in the long run and at a larger spatial scale because their introduction is rarely associated with a rapid benefit for the farmers in terms of an increase in land or labour productivity and is often contingent upon incentives.  相似文献   

14.
坝地沉积旋回泥沙养分变化及其对小流域泥沙来源的解释   总被引:7,自引:1,他引:6  
黄土高原广泛分布的坝地沉积泥沙中赋存了大量小流域侵蚀特征及侵蚀环境变化的信息,泥沙特性的变化则是这些信息的直接体现。该文通过对比分析淤地坝沉积旋回泥沙中和坝控小流域内不同泥沙源地土壤中有机质、全氮、全磷和全钾的含量,发现小流域内土壤养分含量变异性明显大于沉积旋回泥沙中的变异性,沉积旋回泥沙养分含量与沟壁土壤中的相接近,其中与沟壁中的全氮、全磷和全钾无显著差异(p>0.05),但显著小于荒草地和坡耕地中的有机质、全氮和全磷含量(p<0.05),表明淤地坝运行期间小流域泥沙主要来源于沟壁坍塌和沟道扩展,重力侵蚀和沟蚀是主要侵蚀类型;有机质和全氮在坝地沉积旋回中呈明显阶段性变化,分析认为其反映了农村土地联产承包责任制对小流域土地利用和土壤侵蚀的影响。  相似文献   

15.
Gully erosion reduces agricultural productivity by destroying valuable land resources, increases sediment concentrations, reduces water quality, and fills up reservoirs. Gully rehabilitation has proven to be challenging especially in the high‐rainfall areas of the Ethiopian Highlands and has therefore had limited success. This paper describes a successful low‐cost gully rehabilitation effort with community participation in the Birr watershed in the Blue Nile basin that begun in early 2013. Initially, farmers were reluctant to participate for religious reasons, but with the aid of local priests and respected elders, community discussions, and a visit to a rehabilitated gully, a consensus was reached to rehabilitate a 0·71‐ha upland gully. The rehabilitation measures consisted of regrading the gully head at a 45° slope, constructing low‐cost check dams from locally available materials, and planting Pennisetum purpureum grass and Sesbania sesban. At the end of the first post‐implementation rainy season, 2,200 tons of soil was conserved by the constructed check dams and newly planted vegetation, compared with soil losses of 680 and 560 tons in two untreated, nearby gullies. In 2014, an additional 3,100 tons of soil was conserved. In 2013, the marginal rate of return (MRR) on the gully rehabilitation investment was 2·6 based on the value of increased forage production alone. When we include trapped soil nutrient values, the rehabilitation MRR was increased to 10. Although these numbers are impressive, the best proof of the success was that farmers on their own initiative rehabilitated an additional five gullies in 2014. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

16.
基于Google Earth影像的横断山区沟蚀及侵蚀沟类型调查研究   总被引:2,自引:0,他引:2  
[目的]探讨横断山区侵蚀沟的类型、分布特征及影响因素,为研究沟蚀对横断山区土壤侵蚀及土地退化的影响提供依据。[方法]基于Google Earth高清影像结合GIS的方法,基于可见性的基本原则,对横断山区开展侵蚀沟的抽样调查。共布设调查单元2 242个,每个单元尺寸1km×1km。[结果]共有571个调查单元发现有侵蚀沟分布,占调查单元总数的25.5%,平均沟壑密度为2.20km/km2。沟蚀在海拔低于1 500m的区域发育显著,沟壑密度随坡度增加而增长,与年降雨相关性较弱。草地是沟蚀发育的主要土地利用类型,燥红土的沟蚀分布率及平均沟壑密度显著高于其他土壤类型。通过总结国内外现有的侵蚀沟分类体系及其异同,结合调查结果,判定该次调查的横断山区侵蚀沟类型主要为切沟和冲沟(包括有泥石流事件的冲沟)。[结论]横断山区切沟和冲沟分布广泛,发育强烈,其分布受海拔、坡度、土地利用及土壤类型等因素的影响较为显著。  相似文献   

17.
黑土区侵蚀沟损毁耕地,威胁粮食生产,研究侵蚀沟发展速度与发育现状,对揭示侵蚀沟发育机理和保护黑土地具有重要意义。为研究近50年侵蚀沟损毁耕地速度和发育特征,分别在典型黑土区3个纬度带选取坡度约为1%、2%和3%的9个共计约378 km2的典型黑土农田单元,并利用1970年、2011年和2021年卫星影像结合无人机和地面测量的结果进行计算与统计。结果表明,侵蚀沟数量在3个历史时期持续增加,剔除因治理而消失的311条,实际增加了958条,北部嫩江增加速度高于中部海伦和南部巴彦,而同一纬度区大坡度(3%)比小坡度(1%和2%)农田单元内侵蚀沟数量增长更快。人为治理和更高强度耕种导致侵蚀沟面积降低(1970-2011年)然后再增加(2011-2021年)的V型走势,但由侵蚀沟发育而实际损毁耕地的面积持续扩张,近10年年均损毁耕地面积0.1%,3个区域的损毁速度相近。从南往北3个区域侵蚀沟起始发育时间分别是1920s、1940s和1950s,与开垦时间先后顺序一致。典型黑土区侵蚀沟经历了谷底沟发育、沟系形成、多样化发育3个阶段,其中嫩江处在第二阶段,而海伦和巴彦处在第三阶段,即老沟、新沟、次生沟、浅沟多样化发育阶段。人为治理和促进侵蚀沟发育的较量,决定典型黑土区侵蚀沟的发育走势。研究为典型黑土区侵蚀沟防治提供科学依据。  相似文献   

18.
土壤侵蚀严重破坏土地资源,是全球性的环境问题,切沟侵蚀是土壤侵蚀的重要表现形式,近年来极端暴雨频发加剧了切沟侵蚀的发生和发展。为了研究气候变化条件下新成切沟的形成与发育规律,该研究以陕北子洲岔巴沟流域王武沟小流域为研究区,基于无人机航摄影像,以2017年陕北"7·26"暴雨新成切沟为研究对象,分析新成切沟发生规律,并探讨在之后的3 a中其发育特征、与原有切沟发育的差异性及其与地形参数的关系。结果表明:1)在"7·26"暴雨中,王武沟发育新成切沟45条,约101条/km2,可分为坡面切沟、梯田切沟、道路切沟和底部切沟四类,以坡面切沟最多,底部切沟和梯田切沟总体更宽、面积更大;生产道路、淤地坝和坡耕地在暴雨条件下是最容易发生切沟的地块;2) 新成切沟在形成之后的3 a内沟头发育较原有切沟更为迅速。34.48%的新成切沟沟头进一步前进,这一数值为原有切沟的1.32倍;新成切沟前进距离均值是原有切沟的3倍,达0.58 m/a;3)汇水面积增加可显著促进切沟沟头发育,是模拟切沟沟头前进速率的重要地形指标。可见,极端降雨条件下研究区土壤侵蚀严重,新成切沟发生之后的3 a内溯源尤为迅速,应给予特别关注,加强对这类切沟的预防与治理。  相似文献   

19.
砒砂岩区典型淤地坝沉积泥沙特征及来源分析   总被引:3,自引:1,他引:2  
黄土高原地区的淤地坝是拦减入黄泥沙的关键措施,尤以对泥沙具有绝对控制的"闷葫芦"淤地坝为甚。为研究淤地坝对侵蚀泥沙的拦蓄作用,以砒砂岩区皇甫川流域园子沟淤地坝为研究对象,采集坝地淤积剖面及沟间地、沟谷地表层样品,对沉积旋回进行断代分析,计算泥沙贡献率,反演其淤积过程。结果表明:坝地沉积泥沙粒径分布以2~0.05 mm砂粒为主,其次为粉粒、黏粒,砂粒中以极细砂和细砂占比最多。园子沟坝控流域内侵蚀性降雨事件对应的最小日降雨量为22.8 mm;淤地坝运行可划分为2个阶段,前期主要依靠坝体拦蓄泥沙,后期随着拦蓄泥沙的增多,减蚀作用凸显。坝地沉积泥沙主要来源为沟谷地,贡献率达71.4%,沟间地为28.6%,其中沟间地侵蚀产沙并非受植被唯一影响,在降雨量>45.4 mm时,地形因素会限制侵蚀的加剧。  相似文献   

20.
Gully development in the Moldavian Plateau of Romania   总被引:1,自引:0,他引:1  
Ion Ionita   《CATENA》2006,68(2-3):133
Gully erosion has been recognized as an important environmental threat in the Moldavian Plateau of Eastern Romania. The main objective of this study was to define the process-based gully development by providing quantitative information from long-term field measurements in small catchments.Three main areas of monitoring gullies were explored: aerial photographs of flights in 1960 and 1970, classical leveling and repeated survey through a particular close stakes grid after 1980. The Caesium-137 technique has been used effectively in the areas of deposition of gully sediments to obtain reliable information on dating specific levels of sediments and to provide chronological measures of gully development.Most of the discontinuous gullies exhibit both proper gullying, mainly if not exclusively by gully head advance, and aggradation of the gully basin floor. Results indicated that the mean gully head retreat was 0.92 m year− 1 and the mean areal gully growth was 17.0 m2 year− 1. Both values indicate a slow erosion rate for this area. The average annual regime of gullying is pulsatory, one that is best described by great fluctuations. Conventional measurements on sedimentation over the period 1987–1997 indicate a higher rate of aggradation in the upper half of the gully floor. Information on the Caesium-137 depth profile was used to provide estimates of a mean sedimentation rate of 4.4 cm year− 1 over the period 1963–1996 and 2.5 cm year− 1 after 1986 for the short successive discontinuous gullies. A new classification of the discontinuous gullies based on two criteria, respectively, the field patterns and the rate of aggradation within the gully basin floor was established.For continuous gullies, linear gully head retreat, areal gully growth and eroded material rates were quantified for three periods (1961–1970, 1971–1980 and 1981–1990). Results indicate that gully erosion has decreased since 1960. This gullying decline is due to the rainfall distribution, and the increased influence of soil conservation practices. The mean gully head retreat of 12.5 m year− 1 between 1961–1990 was accompanied by a mean areal gully growth of 366.8 m2 year− 1 and a mean erosion rate of 4168 t year− 1. As with discontinuous gullies, continuous gullies showed pulsatory development.The critical period for gullying over 1981–1996 covers 4 months from Mid March to Mid July in an area with mean annual precipitation around 500 mm. Another main finding of this 16-year stationary monitoring was that 57% of the total gullying occurred during the cold season, with the remainder during the warm season. Of the total gully growth, 66% results from only four years (1981, 1988, 1991 and 1996), when a greater amount of precipitation fell.  相似文献   

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