黑土坡面不同粒级泥沙流失特征分析

2019-12-19 01:13沈海鸥肖培青李洪丽牟廷森贺云锋
农业工程学报 2019年20期
关键词:汇流粒级黑土

沈海鸥,肖培青,李洪丽,牟廷森,贺云锋

黑土坡面不同粒级泥沙流失特征分析

沈海鸥1,肖培青2※,李洪丽1,牟廷森1,贺云锋1

(1. 吉林农业大学资源与环境学院,长春 130118;2. 黄河水利科学研究院水利部黄土高原水土流失过程与控制重点实验室,郑州 450003)

不同粒级泥沙流失特征研究可揭示坡面侵蚀机理,表征土壤养分流失状况;而现有研究缺少对不同粒级泥沙流失速率及流失比例的过程性研究。为此,该研究基于连续汇流冲刷试验,研究汇流冲刷次数和坡度对黑土坡面不同粒级泥沙流失特征的影响。试验处理包括6次连续汇流冲刷(1 L/min,每次历时60 min)和2个黑土区典型坡度(5°和10°)。结果表明,汇流冲刷次数对不同粒级泥沙流失速率及比例的影响较坡度的影响明显。试验条件下,<0.25 mm泥沙流失比例最大,其次为1~2、2~5、0.5~1、0.25~0.5、>5 mm泥沙流失比例。随着汇流冲刷次数的增加,<0.25 mm泥沙的平均流失速率由1 965.7~6 698.4 g/(m2·h)显著减小为59.5~80.0 g/(m2·h),该粒级泥沙流失比例亦总体呈现减小的趋势,而1~2 mm泥沙流失比例总体呈现增加的趋势,二者作为侵蚀泥沙的主体,其变化具有明显规律性。因此,<0.25 mm和1~2 mm泥沙流失特征应作为黑土区土壤侵蚀研究的重要部分,进而指导防治措施的布设;同时,建议采用适宜的覆盖措施防治黑土坡面细小颗粒泥沙的流失。

土壤;径流;侵蚀;泥沙粒级;汇流冲刷

0 引 言

坡耕地是东北黑土区土壤侵蚀最严重的区域之一,宝贵的黑土资源流失、土地生产力降低,已经严重制约黑土区农业生产和经济发展,威胁着中国的粮食安全[1-3]。春季融雪或降雨形成的地表径流可携带搬运大量泥沙,这些侵蚀泥沙通常由团聚体和土壤颗粒组成,与原地土壤物质的颗粒组成明显不同[4-5]。由于径流优先搬运含有大量养分的细颗粒,且搬运距离较远[6-7],导致坡面土壤颗粒粗化,其对土壤造成的危害难以进行人为修复[8]。因此,侵蚀泥沙颗粒组成的变化可作为衡量土壤粗化程度的重要指标[9]。泥沙粒径分布决定孔隙的数量搭配、形态特征及对外营力的敏感性,进而影响径流在坡面的运移方式和途径,反过来又影响土壤侵蚀[10-11]。可见,研究不同粒级泥沙流失特征具有重要意义。已有研究表明,汇流冲刷及坡度是影响黑土坡面土壤侵蚀的主要因素[12-13],但是二者对侵蚀泥沙颗粒流失特征的影响研究较少,尤其缺少过程性研究成果。此外,黑土坡面土壤侵蚀过程中,<0.25 mm泥沙流失比例最高,不同研究中,其流失比例分别为45.7%~74.2%[14]、82.5%~98.3%[15]、47.7%~99.6%[16],同时,0.25~0.5、0.5~1、1~2、2~3、>5 mm粒级的泥沙流失比例也呈现一定的变化特征。在紫色土研究中,侵蚀泥沙中<1 mm的泥沙变化明显,流失量较大[17];在棕壤土研究中,>1 mm的泥沙流失量最少[18];在红壤研究中,<2 mm的泥沙流失量最大[10]。可见,目前对于侵蚀泥沙粒级的划分还存在一定争议,针对不同土壤的研究结果也有一定差异。鉴于此,本文基于连续汇流冲刷试验方法,应用径流小区,研究汇流冲刷次数和坡度对黑土坡面不同粒级泥沙流失速率和流失比例变化特征的影响,以期深化坡面土壤侵蚀过程研究,为东北黑土区坡耕地土壤侵蚀防治提供理论指导。

1 材料与方法

1.1 研究区概况

试验于2018年4月在吉林农业大学水土保持科研基地(125°21′ E,43°52′ N)试验径流小区内进行。研究区属于温带大陆性季风气候,具有干湿适中、四季分明的气候特征;年均气温4.8 ℃,年均降水量617 mm[19]。试验地位于典型黑土区,土壤为黑土,砂粒(当量粒径大于50m)质量分数为10.2%,粉粒(当量粒径2~50m)质量分数为9.6%,黏粒(当量粒径小于2m)质量分数为80.2%,有机质(重铬酸钾氧化—外加热法)质量分数25.6 g/kg[20]。

1.2 试验设计

试验径流小区依据我国标准径流小区规格进行设计,即20 m(水平投影长)×5 m(宽);为模拟休耕期坡面,其坡面设计为裸露处理,耕作层平均土壤容重为1.20 g/cm3;坡度依据东北黑土区坡耕地地形特征设计为5°和10°[12]。径流小区底部设集流装置,用于收集试验过程中的径流泥沙样品;径流小区上部设稳流装置,稳流箱规格为0.5 m(长)×5 m(宽)×0.5 m(深),稳流箱中设置稳流板,以提供稳定径流均匀流向黑土坡面(图1)。

图1 试验装置

根据长春国家基准气候站1983—2012年的暴雨资料显示,20年一遇的每小时降雨量接近60 mm[21],将其换算为径流率即为本研究设计的汇流冲刷率1 L/min。为了详细观测黑土坡面水土流失特征,本研究采用连续汇流冲刷研究方法,至坡面侵蚀速率明显减小为200 g/(m2·h)左右时停止冲刷,冲刷次数为6次,每次冲刷试验历时60 min,冲刷间隔为24 h[22],后一次冲刷是在前一次冲刷坡面的基础上进行,二者既有继承性又有独立性。每个试验处理重复两次。

1.3 试验方法

为了确保汇流冲刷试验的准确性,试验开始前对冲刷率进行率定,实测冲刷率与目标冲刷率的差值小于5%时方可进行正式模拟试验。坡面开始产流后即接取径流泥沙样品,取样间隔为1 min或2 min,取样个数为29~37个;从中,按照试验历时均匀取出10~12个径流泥沙样品直接通过5、2、1、0.5和0.25 mm的套筛进行筛分处理,并转移至铝盒中。汇流冲刷试验停止后,称取径流泥沙的总质量,静置后倒掉其上清液,转移至铝盒中,与筛分后的各粒级泥沙一并进行烘干称取质量[23]。

1.4 数据处理

应用Excel 2016、SPSS 19.0进行数据处理与分析:采用Excel 2016绘制连续冲刷处理下不同粒级泥沙流失比例随时间的变化趋势图;采用SPSS 19.0中单因素方差分析(One-way ANOVA)、双因素方差分析(Two-way ANOVAS)和多重比较(LSD),进行显著性水平检验(<0.05)。

2 结果与分析

2.1 连续汇流冲刷及坡度对不同粒级泥沙流失速率的影响

通过对比6次连续汇流冲刷处理不同粒级泥沙的平均流失速率(表1),发现随着汇流冲刷次数的增加,<0.25 mm泥沙流失速率在坡度为5°时由1 965.7 g/(m2·h)显著减小为80.0 g/(m2·h),第1次冲刷处理的该粒级泥沙流失速率是第2次冲刷处理的1.8倍,以此类推,这一倍数变化范围为1.6~2.4倍;在坡度为10°时由6 698.4 g/(m2·h)显著减小为59.5 g/(m2·h),第1次冲刷处理的该粒级泥沙流失速率是第2次冲刷处理的3.5倍,以此类推,这一倍数变化范围为1.5~3.5倍。当坡度由5°增加为10°,第1~3次冲刷处理的<0.25 mm泥沙流失速率显著增加1.5~3.4倍,而第4~6次冲刷处理的该粒级泥沙流失速率无显著差异。

表1 连续汇流冲刷处理下5°和10°坡面不同粒级泥沙的平均流失速率

注:相同坡度及相同泥沙粒级条件下数据后不同小写字母表示不同冲刷处理间差异显著,相同冲刷次数及相同泥沙粒级条件下数据后不同大写字母表示5°和10°坡面处理间差异显著(< 0.05)。

Note: Different lowercase letters for the same sediment gradation at the same slope gradient indicate a difference of significance at the< 0.05 between successive inflow scour treatments. Different capital letters for the same sediment gradation at the same inflow scour event indicate a difference of significance at the< 0.05 between 5° and 10° treatments.

粒级0.25~0.5 mm和0.5~1 mm泥沙的平均流失速率随着汇流冲刷次数的增加而显著降低,至第5次冲刷减小到相对稳定,其后无显著性差异(表1)。对于5°坡面,第1次冲刷处理的0.25~0.5 mm和0.5~1 mm粒级泥沙流失速率分别是第2次冲刷处理的1.1倍和1.4倍,以此类推,这一倍数分别变化于1.1~2.7倍和1.3~2.5倍;对于10°坡面,这一倍数变化范围均为1.4~2.4倍。随着坡度由5°增加到10°,0.25~0.5 mm泥沙流失速率仅在第1次冲刷处理下显著增加,在其后的冲刷处理中未表现出显著性差异;0.5~1 mm泥沙流失速率在第1~3次冲刷处理下显著增加1.5~1.6倍,在其后的冲刷处理中未表现出显著性差异。

对于5°坡面,1~2 mm泥沙的平均流失速率随着汇流冲刷次数的增加而显著降低;第1次冲刷处理的该粒级泥沙流失速率是第2次冲刷处理的1.2倍,以此类推,这一倍数变化范围为1.2~3.0倍(表1)。对于10°坡面,第2次冲刷处理下1~2 mm泥沙流失速率较第1次冲刷处理增加了38.6%,其后随着汇流冲刷次数的继续增加而显著降低;第2次冲刷处理的该粒级泥沙流失速率是第3次冲刷处理的1.7倍,以此类推,这一倍数变化范围为1.7~2.4倍。通过对比5°和10°条件下1~2 mm泥沙流失速率发现,除第1次和第2次冲刷处理外,其余处理未呈现出显著性差异,且第1次和第2次冲刷处理下1~2 mm泥沙流失速率未表现出一定规律。

粒级2~5 mm泥沙的平均流失速率随着汇流冲刷次数的增加总体呈先增加后减小的变化(表1)。对于5°和10°坡面,第2次冲刷处理下2~5 mm泥沙流失速率分别较第1次冲刷处理增加了10.8%和26.1%,其后随着汇流冲刷次数的继续增加而显著降低;第2次冲刷处理的该粒级泥沙流失速率均是第3次冲刷处理的2.0倍,以此类推,5°和10°坡面这一倍数变化范围分别为1.8~2.7倍和1.3~2.7倍。随着坡度由5°增加为10°,第1~3次冲刷处理的2~5 mm泥沙流失速率显著增加1.1~1.2倍,而第4~6次冲刷处理的泥沙流失速率无显著差异。

对于5°坡面,>5 mm泥沙的平均流失速率相对较小,第1~2次冲刷处理间未呈现显著差异,从第3次处理开始逐渐减小,其后无显著性差异(表1)。对于10°坡面,随着汇流冲刷次数的增加,>5 mm泥沙流失速率总体呈现减小趋势。通过对比5°和10°条件下>5 mm泥沙流失速率发现,除第6次冲刷处理外,其余处理均随坡度的增加而显著增加。

2.2 连续汇流冲刷及坡度对不同粒级泥沙流失比例的影响

通过对比6次连续冲刷处理下不同粒级泥沙流失比例随时间的变化(图2),发现<0.25 mm泥沙流失比例最高,5°和10°条件下,6次冲刷试验该粒级泥沙的平均流失比例分别为43.0%和47.0%;随时间呈现较大幅度的波动变化,未表现出明显的增加或减小趋势,5°和10°条件下,波动幅度分别为15.8%~39.7%和20.7%~39.0%。随着汇流冲刷次数的增加,该粒级泥沙流失比例总体呈现减小的趋势。对比两个坡度下<0.25 mm泥沙流失比例发现,随着坡度的增加,第1次冲刷处理的流失比例增加,第6次冲刷处理流失比例减小,第2~5次冲刷处理的流失比例无明显变化。

粒级0.25~0.5 mm和0.5~1 mm泥沙流失比例相对较小,5°坡面,6次冲刷试验泥沙平均流失比例分别为9.0%和9.7%,10°坡面,其平均流失比例分别为8.4%和9.6%;随时间呈现小幅度波动变化,未表现出明显的增加或减小趋势,波动幅度分别为4.8%~12.1%和4.6%~13.9%(图2)。随着汇流冲刷次数的增加,两个粒级泥沙流失比例总体呈现为逐渐增加的趋势。坡度对0.25~0.5 mm和0.5~1 mm泥沙流失比例随时间的变化未呈现明显影响。

图2 连续冲刷处理下5°和10°坡面不同粒级泥沙流失比例随时间的变化

粒级1~2 mm泥沙流失比例相对较大,5°和10°条件下,6次冲刷试验该粒级泥沙的平均流失比例分别为21.6%和16.8%(图2)。1~2 mm泥沙流失比例随时间未表现出明显的增加或减小趋势,总体呈现波动变化;5°和10°条件下,其波动幅度分别变化于12.5%~25.9%和9.1%~34.1%。随着汇流冲刷次数的增加,该粒级泥沙流失比例总体呈现为增加的趋势,其中增加幅度比较大的处理是从第3次冲刷开始。当坡度由5°增加为10°时,1~2 mm泥沙流失比例平均减小了22.0%,其中第1~4次冲刷处理表现更加明显。

5°和10°条件下,6次冲刷试验2~5 mm泥沙的平均流失比例分别为15.6%和14.4%,流失比例随时间呈现波动变化,未表现出明显的增加或减小趋势,其波动幅度分别为9.4%~21.1%和9.7%~22.2%(图2)。随着汇流冲刷次数的增加,2~5 mm泥沙流失比例总体呈现为先增加后减小的趋势,转折点从第4次冲刷开始。当坡度由5°增加为10°时,第1~2次冲刷处理的2~5 mm泥沙流失比例平均减小了39.7%,第3~4次冲刷处理无明显差异,第5~6次冲刷处理平均增加1.29倍。

粒级>5 mm泥沙流失比例最小,5°和10°条件下,6次冲刷试验该粒级泥沙的平均流失比例分别为1.1%和3.9%,随时间呈现波动变化,未表现出明显的增加或减小趋势,其波动幅度分别为0~3.6%和3.5%~14.1%(图2)。第1~4次冲刷处理的>5 mm泥沙流失比例比较相近,第5~6次冲刷处理的>5 mm泥沙流失比例显著减小,甚至为0。

3 讨 论

随着汇流冲刷试验的持续进行,坡面可供侵蚀的泥沙颗粒逐渐减少[24],特别是细小土壤颗粒及微团聚体[5,17],由于径流的选择性搬运特征[6],使其在前期试验中流失明显,后期流失逐渐减小。此外,坡度越大,坡面物质稳定性越低,径流平均流速越大[25-26],导致试验前期的<0.25 mm泥沙流失速率和比例均随坡度的增大而明显增加;随着冲刷次数的增加,其流失速率逐渐减小,坡度越大,其变化趋势越明显,导致第4~6次冲刷中5°和10°坡面该粒级泥沙流失速率达到比较接近的状态,未呈现显著性差异。研究表明,<0.25 mm泥沙是黑土坡面侵蚀的主体部分[27],且该粒级泥沙携带大量土壤养分[7],防治前期阶段的细颗粒泥沙流失,可有效保护黑土土壤,减轻土壤养分流失;而坡度对<0.25 mm泥沙流失比例的影响受坡面可供侵蚀物质多少的影响。

汇流冲刷次数对0.25~0.5 mm和0.5~1 mm泥沙流失具有明显的影响;而坡度对该粒级泥沙流失的影响在前期比较明显,在后期无显著影响。尽管0.25~0.5 mm和0.5~1 mm泥沙流失比例随着汇流冲刷次数的增加而逐渐增加,但是由于其总体流失比例较小,表明在全部粒级泥沙中,0.25~1 mm泥沙不属于流失敏感部分,即不是侵蚀泥沙的主体。而1~2 mm泥沙在侵蚀泥沙中占有较大比例,其流失比例亦随汇流冲刷次数的增加而逐渐增加;坡度对该粒级泥沙流失速率的影响相对较小,但是对其流失比例的影响表现为随坡度的增加而减小。因此,建议在开展黑土区土壤侵蚀与土壤养分研究中增加对1~2 mm泥沙流失特征的关注。

作为粒径较大的2~5 mm泥沙,与5°坡面相比,10°坡面上的泥沙更容易被搬运[26],但是由于第1~2次冲刷处理的坡面可供侵蚀的物质比较充足,径流优先搬运其他粒级泥沙,使其流失所占比例反而低于5°坡面;在第3~4次冲刷中5°和10°处理达到比较接近的状态;在第5~6次冲刷中,由于可被搬运的坡面物质明显减少,10°坡面较大的径流冲刷能力[23]开始起到主要作用,导致2~5 mm泥沙流失比例高于5°坡面。结果表明,2~5 mm泥沙在侵蚀泥沙中占有中等大小比例,其流失速率和比例随着汇流冲刷次数的增加总体呈现为先增加后减小的变化;坡度对该粒级泥沙流失的影响受坡面可供侵蚀物质多少的影响。

即使相对较大的颗粒(>5 mm)难以被优先选择搬运[10,15],但是在坡度较大(~10°)条件下,依然会被搬运并流失;汇流冲刷次数对>5 mm泥沙流失的影响与坡度有关,在坡度较小时,其影响相对较小;在坡度较大时,其影响相对较大。随着汇流冲刷次数的增加,坡面可被侵蚀物质严重不足,坡面物质呈现土壤颗粒粗化现象[8],大粒级泥沙形成相对稳定的结构,更加难以搬运。结果表明,>5 mm泥沙在侵蚀泥沙中占有比例最小,其流失比例随着汇流冲刷次数的增加总体呈现为减小的变化;随坡度的增加,该粒级泥沙流失比例平均增大3.5倍。可见,黑土裸露坡面在承受5次左右1 L/min的汇流冲刷后,其坡面粗骨化严重,土壤对环境变化的缓冲能力及土地生产力严重降低。因此,建议采用适宜的覆盖措施[28]保护黑土坡面,可有效防治东北黑土区休耕期坡面土壤侵蚀[29]。

综上可见,汇流冲刷次数和坡度对不同粒级泥沙的流失速率和比例具有一定影响,对比显著性分析结果发现前者的影响较后者明显。试验条件下,各粒级泥沙流失比例从大到小的顺序为<0.25、1~2、2~5、0.5~1、0.25~0.5、>5 mm。各粒级泥沙流失比例随时间呈现波动变化,多数情况下未呈现明显的增加或减小趋势。坡度对不同粒级泥沙流失比例的影响比较复杂[30]。此外,在以往研究中,多关注<0.25 mm泥沙流失特征[14],但是本研究中的5°坡面,粒级<2 mm泥沙流失速率均随着汇流冲刷次数的增加而减小;而10°坡面粒级<1 mm泥沙流失速率均随着汇流冲刷次数的增加而减小。因此,<0.25 mm和1~2 mm泥沙流失特征应作为黑土坡面土壤侵蚀研究的重要部分,进而指导适宜防治措施的布设。

4 结 论

通过连续汇流冲刷试验,研究汇流冲刷次数和坡度对黑土坡面不同粒级泥沙流失特征的影响,得到如下研究结论:

1)汇流冲刷次数及坡度对不同粒级泥沙的流失速率及比例具有一定影响,其中前者的影响较后者明显。

2)随着汇流冲刷次数的增加,<0.25 mm泥沙平均流失速率在坡度为5°时由1 965.7 g/(m2·h)显著减小为80.0 g/(m2·h),在坡度为10°时由6 698.4 g/(m2·h)显著减小为59.5 g/(m2·h)。因此,防治前期阶段的细颗粒泥沙流失,可有效保护富含养分的表层黑土。

3)本研究中各粒级泥沙流失比例从大到小的顺序为<0.25、1~2、2~5、0.5~1、0.25~0.5、>5 mm。5°和10°条件下,6次冲刷试验<0.25 mm泥沙流失的平均比例分别为43.0%和47.0%,1~2 mm泥沙流失的平均比例分别为21.6%和16.8%。随着汇流冲刷次数的增加,<0.25 mm泥沙流失比例总体呈现减小的趋势,而1~2 mm泥沙流失比例总体呈现为增加的趋势,二者变化具有互补特征。因此,在开展黑土区土壤侵蚀研究中,<0.25 mm和1~2 mm泥沙均应作为重要研究对象。

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Analysis of sediment particle loss at different gradations on Mollisol hillslopes

Shen Haiou1, Xiao Peiqing2※, Li Hongli1, Mou Tingsen1, He Yunfeng1

(1.,,130118,; 2.,,450003,)

Studies of sediment particle losses at different gradations can reveal hillslope soil erosion mechanisms and can reflect soil nutrient loss characteristics. However, there is a lack of process research on the loss rates and ratios of sediment with different sizes in existing research. This study was conducted to study the effects of inflow scour times and slope gradients on the loss characteristics of sediment with different sizes on hillslopes in the Chinese mollisol region based on a successive inflow scour method. The experiments were conducted at the Scientific Research Base of Soil and Water Conservation, which belongs to Jilin Agricultural University, located in the city of Changchun, Jilin Province. This area represents a typical mollisol region of Northeast China. The soil used in this study is classified as mollisol (USDA Taxonomy), with 10.2% sand (>50m), 9.6% silt (2-50m), 80.2% clay (<2m) and 25.6 g/kg soil organic matter. Natural runoff plots (20 m long and 5 m wide) were subjected to 6 successive inflow scour experiments (1 L/min lasting 60 min each) at two representative slope gradients (5° and 10°). The surrounding hydraulic boundary of each plot was made from a galvanized sheet that was molded to provide a greater rigidity. A runoff collector was attached to the base of the field plot to collect the runoff and sediment samples. An overflow tank, which was 0.5 m long, 5 m wide and 0.5 m deep, was attached to the upper end of the field plot to supply the inflow water. There were 10-12 runoff samples collected during the experiment, and they successively passed through a column of sieves of 5, 2, 1, 0.5 and 0.25 mm diameters to quantify the losses of sediment with different sizes. The results showed that the effects of inflow scour times on the loss rates and loss ratios of sediment with different particle sizes were more obvious than those of the slope gradients. With an increase in inflow scour time, the loss rates of <0.25 mm sediments significantly decreased from 1 965.7-6 698.4 g/(m2·h) to 59.5-80.0 g/(m2·h). The loss rates of <0.25 mm sediments in the former inflow scour treatments were 1.6-2.4 and 1.5-3.5 times greater than those in the latter treatments for the hillslopes of 5° and 10°, respectively. Thus, it is critical to prevent the loss of fine sediments during the early stage of rainfall and runoff events. In this study, the loss ratios of <0.25 mm sediments were the largest, followed by those, in descending order, of 1-2, 2-5, 0.5-1, 0.25-0.5 and >5 mm sediments. The effects of slope gradient on loss ratios of sediment with different sizes were relatively complex. As the inflow scour time increased, the loss ratios of the <0.25 mm sediments generally showed a decreasing trend, but the loss ratios of the 1-2 mm sediments generally exhibited an increasing trend. The <0.25 mm and 1-2 mm sediments were the main components of eroded sediments; furthermore, these sediments were complementary to each other, and their changes had obvious regularities. Therefore, the <0.25 mm and 1-2 mm sediments should be given more attention during studies of soil erosion on the Chinese mollisol hillslopes. Meanwhile, selecting proper mulching measures to control the losses of fine sediments on hillslopes of the mollisol region is also necessary.

soils; runoff; erosion; sediment gradation; inflow scour

沈海鸥,肖培青,李洪丽,牟廷森,贺云锋. 黑土坡面不同粒级泥沙流失特征分析[J]. 农业工程学报,2019,35(20):111-117.doi:10.11975/j.issn.1002-6819.2019.20.014 http://www.tcsae.org

Shen Haiou, Xiao Peiqing, Li Hongli, Mou Tingsen, He Yunfeng. Analysis of sediment particle loss at different gradations on Mollisol hillslopes[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2019, 35(20): 111-117. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2019.20.014 http://www.tcsae.org

2019-03-01

2019-09-20

国家重点研发计划项目(2016YFE0202900);国家自然科学基金项目(41601281,41571276)

沈海鸥,讲师,主要从事土壤侵蚀过程与机理研究。Email:shensusan@163.com

肖培青,教授级高工,主要从事土壤侵蚀与水土保持研究。Email:peiqingxiao@163.com

10.11975/j.issn.1002-6819.2019.20.014

S157

A

1002-6819(2019)-20-0111-07

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