摘要
土壤侵蚀已成为全球性的严重环境问题,而坡耕地是土壤侵蚀发生的主要策源地。农作物作为坡耕地的主要覆盖物,对坡耕地土壤侵蚀的发生和发展有着重要影响。因此,深入研究作物植被对土壤侵蚀的作用,对经济有效地防治侵蚀、完善土壤侵蚀理论有重要的意义。本文以黄土高原主要种植作物玉米、大豆、谷子和小麦为对象,采用室内外人工模拟降雨、田间入渗测定、土壤化学分析等手段,研究了作物植被对降雨再分配、溅蚀、降雨入渗、坡面产流产沙、坡面土壤养分流失等方面的作用,得到了以下主要结论:
(1)作物冠层可将降雨大致分配为冠下穿透雨、茎秆流和冠层截留三部分。随玉米、大豆和谷子的生长,穿透雨量占总降雨量比例分别在约94%~36%、95%~73%,以及85%~55%之间逐渐降低;小麦的冠下穿透雨量所占比例随小麦生长(从返青起身到抽穗后)变化趋势不明显,在约76%~82%之间变化。玉米、大豆和谷子冠下穿透雨量的空间分布很不均匀,局部地点降雨强度可达初始降雨的2~3倍,小麦冠下穿透雨量分布相对均匀。茎秆流量占总降雨比例随玉米、大豆和谷子的生长,分别在约5%~68%、2%~22%,以及7%~32%之间逐渐增加;小麦植株群体不适用茎秆流概念,顺植株流下的水量被定义为小麦行内水量,在总降雨量中约占18%~24%。本研究还提出了物理意义相对明确的单株玉米茎秆流模型。玉米、大豆、谷子和小麦的冠层截留量(换算为作物所占地面上的水深)在作物生长过程中分别在约0.02 mm~0.4 mm、0.05 mm~1 mm、0.05 mm~0.35 mm,以及0.5 mm~1.5 mm之间变化,作物冠层截留量不是降雨再分配的主要部分。
(2)在生长过程中,玉米、大豆、谷子和小麦冠下的平均溅蚀速率与裸地溅蚀速率的比值分别在约40%~80%、25%~60%、45%~89%,以及3%~12%之间变化。大豆冠下平均溅蚀速率随冠层生长逐渐降低,其它三种作物冠下平均溅蚀速率则在作物生长过程中无规律波动。三种禾本科作物冠下的溅蚀速率在80 mm/h雨强下与裸地对照值相比的降低幅度大于在40 mm/h雨强下的降低幅度,大豆在这方面的规律不明显。作物冠下的溅蚀往往集中到少数几个地点发生,溅蚀速率空间变异极大。
(3)在一个生长季内,作物没有对土壤的入渗能力产生显著影响,但是随着作物的生长,降雨在坡面的入渗显著增加。玉米、大豆、谷子和小麦在生长过程中,分别能将降雨在坡面的入渗量相对裸地提高15%~51%、8%~45%、5%~58%,以及110%~120%以上。作物对降雨入渗的促进作用主要不是通过提高土壤入渗能力,而是通过阻滞降雨和径流在坡面的运动,延长径流在一定尺度坡面上的停留时间来实现的。
(4)玉米、大豆、谷子在生长过程中,分别能将产流量相对裸地降低约11%~42%、7%~38%,以及2%~43%;将产沙量分别降低约27%~76%、21%~78%,以及24%~84%。小麦在春季返青期,就能将产流量和产沙量分别降低至裸地的11%左右和1.15%左右,在抽穗后,则进一步降低至裸地的约2.36%和约0.25%,在收割后,产流量和产沙量仍然维持在与收割前相近的极低水平上。本研究以通用土壤流失方程USLE中的覆盖管理因子C为理论指导,计算了作物植被影响下的土壤流失比率(作物覆盖条件下土地的土壤流失量与裸地土壤流失量的比值),并拟合了玉米、大豆和谷子三种作物覆盖下,土壤流失比率与冠层叶面积指数之间的关系式,在种植上述三种作物的条件下,坡面土壤流失比率的变化与叶面积指数之间分别呈现出幂函数、线性函数和对数函数关系。
(5)在本研究中,种植玉米条件下,侵蚀泥沙中养分浓度和养分富集率与裸地的侵蚀泥沙无显著差异,在种植大豆和谷子条件下,侵蚀泥沙中养分浓度和养分富集率高于裸地的侵蚀泥沙,有统计意义上的显著差异。坡面表层土壤浓度在一个作物生长季内降低趋势不明显。不同覆盖条件、降雨强度以及坡度等因素对坡面养分流失的影响主要不是通过改变泥沙养分浓度,而是通过改变泥沙流失总量来实现的,坡面养分流失总量的变化与泥沙流失量的变化趋势相同。
Soil erosion is a severe global environmental problem. Slope land is the main original place of erosion. As the main cover on slope lands, agricultural crops play an important role in soil erosion processes of slope land. Therefore, the thorough research about the influences of crop cover on erosion is important to control erosion economically and effectively, as well as to improve soil erosion theory. This study took corn, soybean, millet, and wheat, which are widely planted on Loess Plateau, as main materials, using methods such as indoor and outdoor simulated rainfall, infiltration measurement in field, and chemical analysis, investigated the effects of crops on rainfall partitioning, splash detachment, rainfall infiltration, runoff and sediment yield, and nutrient losses from slope land. The results showed that:
(1)The canopy of crops partitioned rainfall as there main parts: throughfall, stemflow, and interception storage. As corn, soybean, and millet grew, the ratios of throughfall to total rainfall declined from about 94 to 36%, 95 to 73%, and 85 to 55%, respectively; for wheat, the ratio had no obvious trend as growing (from returning green stage to after heading), and fluctuated between about 76 to 82%. The spatial distribution of throughfall under corn, soybean, and millet was uneven, throughfall intensities at some points under canopy were 2 or 3 times higher than initial rainfall; the distribution of throughfall under wheat canopy was relatively more even. As corn, soybean, and millet grew, the ratios of stemflow to total rainfall increased from about 5 to 68%, 2 to 22%, and 7 to 32%, respectively. The concept of stemflow was not suitable for wheat. Rain water moved along wheat plants was defined as intro-row water, which composed about 18 to 24% in total rainfall amount. A stemflow model for corn which had fairly good physical basis was built in this study. The interception storage (water depth on ground occupied by crops) on corn, soybean, millet, and wheat canopies changed from about 0.02 to 0.4 mm, 0.05 to 1 mm, 0.05 to 0.35 mm, and 0.5 to 1.5 mm, respectively. Interception storage on crop canopy was not a main part in rainfall partitioning process.
(2)As crops grew, the ratios of average splash detachment rates under corn, soybean, millet, and wheat canopies to detachment rates on bare soil changed between about 40 to 80%, 25 to 60%, 45 to 89%, and 3 to 12%, respectively. The average detachment rate under soybean canopy decreased as canopy grew; for other three crops, the average detachment rates under canopy changed irregularly during growing stages. Under canopies of the three gramineous crops, the reduction of detachment rates compared to detachment rate on bare soil were greater under rainfall of 80 mm/h intensity than which under rainfall of 40 mm/h intensity; such phenomenon was not obvious under soybean canopy. Splash detachment often occurred at several points under crop canopy, and appeared extremely high spatial variation.
(3)During one growing season, crops didn’t affect infiltration property of soil significantly. But, rainfall infiltration on slope increased significantly as crops grew. In the growing period, corn, soybean, millet, and wheat enhanced infiltration amount of rainfall by 15 to 51%, 8 to 45%, 5 to 58%, and 110 to 120% compared to bare slope, respectively. The promotion effects of crops on rainfall infiltration were largely caused by slowing down rainfall and runoff movement on slope and prolonging the staying time of runoff on slope with a certain scale, not caused by improving infiltration ability of soil.
(4)As corn, soybean, and millet grew, compared to bare soil, crop covers reduced runoff yield by about 11 to 42%, 7 to 38%, and 2 to 43%, and reduced sediment yield by about 27 to 76%, 21 to 78%, and 24 to 84%, respectively. In spring, when wheat started to grow again, the runoff and sediment yield from wheat plots were about 11% and 1.15% of that from bare plots. After heading, those ratios reduced to 2.36% and 0.25%, respectively. Even after harvest, the runoff and sediment yield from wheat plots were at a low level as that before harvest. Soil loss ratios (ratio of soil loss under crop cover to that from bare soil slope) were calculated taking the cover and management factor C in USLE as basis. Soil loss ratios under corn, soybean, and millet cover conditions were decreased exponentially, linearly, and logarithmically as leaf area indexes of the three crop canopies increased, respectively.
(5)In this study, nutrient concentrations and enrichment ratios of nutrients in sediment from corn plots were not significantly different from that from bare plots. Under soybean and millet cover, nutrient concentrations and enrichment ratios of nutrients in sediment were higher than that from bare plots, the differences were significant statistically. Nutrients concentrations in top soil on slope didn’t decline obviously during one growing season of crops. The influences of different cover conditions, rainfall intensities, and slope gradients on nutrient loss from slope were not caused by changing nutrients concentrations in sediment, but caused by changing total sediment yield. Nutrient loss and sediment loss had the same trend of changing.
引文
[1]王礼先,朱金兆.水土保持学[M].北京:中国林业出版社,2005.
[2]董哲仁.水土保持可持续发展研究[M].北京:中国水利水电出版社,2005.
[3]郑粉莉,江忠善,高学田.水蚀过程与预报模型[M].北京:科学出版社,2008.
[4]唐克丽等.中国水土保持[M].北京:科学出版社,2004.
[5]张科利,唐克丽.人类耕垦对现代侵蚀加速作用的评价[J].水土保持通报,1990,10(5):1-4.
[6]王占礼,邵明安,李勇.黄土地区耕作侵蚀过程中的土壤再分布规律研究[J].植物营养与肥料学报,2002,8(2):168-172.
[7]王占礼,邵明安,雷廷武.黄土区耕作侵蚀及其对总土壤侵蚀贡献的空间格局[J].生态学报,2003,23(7):1328-1335.
[8]Laws E. A.著,余刚,张祖麟等译.水污染导论[M].北京:科学出版社,2004.
[9]唐克丽.退耕还林还牧与保障食物安全的协调发展问题[J].中国水土保持,2000,8:35-37.
[10]吴发启,赵晓光,刘秉正.缓坡耕地侵蚀环境及动力机制分析[M].西安:陕西科学技术出版社,2001.
[11]苏斯. H.И.著,水利部专家工作室译.土壤侵蚀及其防治[M].北京:水利出版社,1956.
[12]Lamm F. R.,Manges H. L.. Partitioning of the sprinkler irrigation water by a corn canopy[J]. Transactions of the ASAE.,2000,43:909-918.
[13]Steiner J. L.,Kanemasu E. T.,Clark R. N.. Spray losses and partitioning of water under a center pivot sprinkler system[J]. Transactions of the ASAE.,1983,26:1128-1134.
[14]李久生.喷灌均匀系数对土壤水分空间分布及作物产量影响的研究现状[J].农业工程学报,1998,14(2):132-137.
[15]桑以琳.土壤学与农作学[M].北京:中国农业出版社,2005.
[16]Haynes J. L.. Ground rainfall under vegetative canopy of crops[J]. Journal of the American Society of Agronomy,1940,32:176-184.
[17]Quinn N. W.,Laflen J. M.. Characteristics of raindrop throughfall under corn canopy[J]. Transactions of the ASAE.,1983,26(5):1445-1450.
[18]李王成,黄修桥,龚时宏等.玉米冠层对喷灌水量空间分布的影响[J].农业工程学报,2003,19(3):59-62.
[19]王迪,李久生,饶敏杰.玉米冠层对喷灌水量再分配影响的田间试验研究[J].农业工程学报,2006,22(7):43-47.
[20]杜尧东,王建,刘作新等.春小麦田喷灌的水量分布及小气候效应[J].应用生态学报,2001,12(3):398-400.
[21]Armstrong C. L.,Mitchell J. K.. Transformations of Rainfall by Plant Canopy[J]. Transactions of the ASAE.,1987,30 (3):688-696.
[22]Moss A. J.,Green T. W.. Erosive Effects of the Large Water Drops (Gravity Drops) that Fall from Plants[J]. Australian Journal of Soil Research,1987,25:9-20.
[23]吴钦孝等.森林保持水土机理及功能调控技术[M].北京:科学出版社,2005.
[24]Gwynne M. D.,Glover J.. Light rainfall and plant survival: Measurement of stem flow run-off[J].Nature,1961,191:1321-1322.
[25]Glover J.,Gwynne M. D.. Light rainfall and plant survival in East Africa I. Maize[J]. Journal of Ecology,1962,50:111-118.
[26]Van Elewijck L.. Stemflow on maize: a stemflow equation and the influence of rainfall intensity on stemflow amount[J]. Soil Technology,1989,2:41-48.
[27]Van Elewijck L.. Influence of leaf and branch slope on stemflow amount[J]. Catena,1989,16:525-533.
[28]Parkin T. B.,Codling E. E.. Rainfall distribution under a corn canopy: Implications for managing agrochemicals[J]. Agronomy Journal,1990,82:1166-1169.
[29]Bui E. N.,Box J. E. Jr.. Stemflow, rain throughfall, and erosion under canopies of corn and sorghum[J]. Soil Science Society of America Journal,1992,56:242-247.
[30]Saffigna P. G.,Tanner C. B.,Keeney D. R.. Non-uniform infiltration under potato canopies caused by interception, stemflow, and hilling[J]. Agronomy Journal,1976,68:337-342.
[31]刘海军,康跃虎,王庆改.作物冠层对喷灌水分分布影响的研究进展[J].干旱地区农业研究,2007,25(2):137-142.
[32]Armstrong C. L.,Mitchell J. K.. Plant canopy characteristics and processes which affect transformation of rainfall properties[J]. Transactions of the ASAE.,1988,31 (5):1400-1409.
[33]Van Dijk A. I. J. M.,Bruijnzeel L. A.. Modelling rainfall interception by vegetation of variable density using an analytical model. Part 2. Model validation for a tropical upland mixed cropping system[J]. Journal of Hydrology,2001,247:239-262.
[34]郝芝建,范兴科,吴普特.喷灌条件下夏玉米冠层对水量截留试验研究[J].灌溉排水学报,2008,27(1):25-27.
[35]王迪,李久生,饶敏杰.喷灌冬小麦冠层截留试验研究[J].中国农业科学,2006,39(9):1859-1864.
[36]刘秉正,吴发启.土壤侵蚀[M].西安:陕西人民出版社,1997.
[37]Sreenivas L.,Johnston J. R.,Hill H. O.. Some relationship of vegetation and soil detachment in the erosion process[J]. Soil Science Society Proceedings,1947,12:471-474.
[38]Morgan R. P. C.. Splash detachment under plant covers: results and implications of a field study[J]. Transactions of the ASAE.,1982,25(4):987-991.
[39]Noble C. A.,Morgan R. P. C.. Rainfall interception and splash detachment with a Brussels sprouts plant: a laboratory simulation[J]. Earth Surface Processes and Landforms,1983,8:569-577.
[40]Finney H. J.. The effect of crop covers on rainfall characteristics and splash detachment[J]. Journal of Agricultural Engineering Research,1984,29:337-343.
[41]Morgan R. P. C.. Effect of corn and soybean canopy on soil detachment by rainfall[J]. Transactions of the ASAE.,1985,28(4):1135-1140.
[42]朱显谟.再论黄土高原国土整治“28字方略”[J].土壤侵蚀与水土保持学报,1995,1(1):4-11.
[43]解文艳,樊贵盛.土壤质地对土壤入渗能力的影响[J].太原理工大学学报,2004,35(5):537-540.
[44]刘贤赵,康绍忠.降雨入渗和产流问题研究的若干进展及评述[J].水土保持通报,1999,19(2):57-62.
[45]解文艳,樊贵盛.土壤结构对土壤入渗能力的影响[J].太原理工大学学报,2004,35(4):381-384.
[46]吴发启,赵西宁,佘雕.坡耕地土壤水分入渗影响因素分析[J].水土保持通报,2003,23(1):16-18.
[47]赵西宁,吴发启,王万忠.黄土高原沟壑区坡耕地土壤入渗规律研究[J].干旱区资源与环境,2004,18(4):109-112.
[48]杨永辉,赵世伟,雷廷武等.耕作对土壤入渗性能的影响[J].生态学报,2006,26(5):1624-1630.
[49]李雪转,樊贵盛.土壤有机质含量对土壤入渗能力影响的试验研究[J].太原理工大学学报,2006,37(1):59-62.
[50]王国梁,刘国彬,周生路.黄土丘陵沟壑区小流域植被恢复对土壤稳定入渗的影响[J].自然资源学报,2003,18(5):529-535.
[51]蒋定生,黄国俊,谢永生.黄土高原土壤入渗能力野外测试[J].水土保持通报,1984,4:7-9.
[52]解文艳,樊贵盛.土壤含水量对土壤入渗能力的影响[J].太原理工大学学报,2004,35(3):272-275.
[53]栗献锋.影响土壤水分入渗特性主要因素的试验研究[J].山西水利科技,2008,1:38-40.
[54]吕刚,吴祥云.土壤入渗特性影响因素研究综述[J].中国农学通报,2008,24(7):494-499.
[55]Prieksat M. A.,Kaspar T. C.,Ankeny M. D.. Positional and temporal changes in ponded infiltration in a corn field[J]. Soil Science Society of American Journal,1994,58:181-184.
[56]卢晓杰,李瑞,张克斌.农牧交错带地表覆盖物对土壤入渗的影响[J].水土保持通报,2008,28(1):1-5.
[57]Barley K. P.. Effects of root growth and decay on the permeability of a synthetic sandy loam[J]. Soil Science,1954,78:205-210.
[58]Gish T. J.,Jury W. A.. Estimating solute travel times through a crop root zone[J]. Soil Science,1981,133:124-130.
[59]Gish T. J.,Jury W. A.. Effect of plant roots and root channels on solute transport[J]. Transactions of the ASAE.,1983,26:440-444.
[60]Meek B. D.,DeTar W. R.,Rolph D.,et al. Infiltration rate as affected by an alfalfa and no-till cotton cropping system[J]. Soil Science Society of American Journal,1990,54:505-508.
[61]Hino M.,Fujita K.,Shutto H.. A laboratory experiment on the role of grass for infiltration and runoff processes[J]. Journal of Hydrology,1987,90:303-325.
[62]Kohl R. A.,Schumacher T. E..透水及不透水覆盖物对土壤入渗率的影响效果[J].水土保持科技情报,2000,2:27-28.
[63]刘立晶,高焕文,李洪文.秸秆覆盖对降雨入渗影响的试验研究[J].中国农业大学学报,2004,9(5):12-15.
[64]陈洪松,邵明安,张兴昌等.野外模拟降雨条件下坡面降雨入渗、产流试验研究[J].水土保持学报,2005,19(2):5-8.
[65]吴长文,王礼先.林地坡面水动力学特性及其阻延地表径流研究[J].水土保持学报,1995,9(2):32-38.
[66]郭忠升,吴钦孝.森林植被对土壤入渗速率的影响[J].陕西林业科技,1996,(3):27-31.
[67]陈步峰,周光益,曾庆波等.热带山地雨林生态系统水文动态特征的研究[J].植物生态学报,1998,22(1):68-75.
[68]陈云明,陈永勤.人工沙棘林水文水土保持作用机理研究[J].西北植物学报,2003,23(8):1357-1361.
[69]许秀丽,罗承德,宫渊波等.四川洪雅县3种植被模式的土壤入渗性能[J].林业科学,2007,43(增1):106-109.
[70]周星魁,王忠科,蔡强国.植被和坡度影响入渗过程的试验研究[J].山西水土保持科技,1996,4:10-13.
[71]赵晓光,吴发启,姚军.人工模拟坡耕地入渗率研究[J].土壤侵蚀与水土保持学报,1999,5(5):39-43.
[72]吴发启,赵西宁,崔卫芳.坡耕地土壤水分入渗测试方法对比研究[J].水土保持通报,2003,23(3):39-41.
[73]陈瑶,张科利,罗利芳等.黄土坡耕地弃耕后土壤入渗变化规律及影响因素[J].泥沙研究,2005,5:45-50.
[74]高鹏,穆兴民.黄土丘陵区不同土地利用方式下土壤水分入渗的对比试验[J].中国水土保持科学,2005,3(4):27-31.
[75]雷廷武,刘汗,潘英华等.坡地土壤降雨入渗性能的径流-入流-产流测量方法与模型[J].中国科学D辑地球科学,2005,35(12):1180-1186.
[76]牛伊宁,沈禹颖,高崇岳等.覆盖和耕作对黄土高原冬小麦土壤入渗特性的影响.山地学报,2006,24(1):13-18.
[77]陈洪松,邵明安,王克林.土壤初始含水率对坡面降雨入渗及土壤水分再分布的影响[J].农业工程学报,2006,22(1):44-47.
[78]王健,吴发启,孟秦倩等.不同利用类型土壤水分下渗特征试验研究[J].干旱地区农业研究,2006,24(6):159-162.
[79]李毅,邵明安.人工草地覆盖条件下降雨入渗影响因素的实验研究[J].农业工程学报,2007,23(3):18-23.
[80]傅斌,王玉宽,朱波.紫色土坡耕地降雨入渗试验研究[J].农业工程学报,2008,24(7):39-43.
[81]Musgrave G. W.. The quantitative evaluation of factors in water erosion-a first approximation[J]. Journal of Soil and Water Conservation,1947,2:133-138.
[82]贾媛媛,郑粉莉,杨勤科.国外水蚀预报模型评述[J].水土保持通报,2003,23(5):82-87.
[83]周正朝,上官周平.土壤侵蚀模型研究综述[J].中国水土保持科学,2004,2(1):52-55.
[84]汪东川,卢玉东.国外土壤侵蚀模型发展概述[J].中国水土保持科学,2004,29(2):35-40.
[85]宋颖.土壤侵蚀模型研究进展及发展方向[J].山西水利科技,2006,3:39-41.
[86]王德,傅伯杰,赵文武等.土壤侵蚀模型研究中的几个问题[J].干旱区地理,2007,30(3):406-413.
[87]罗志军,张俊.土壤侵蚀模型的研究现状与展望[J].安徽农业科学,2007,35(27):8574-8576.
[88]牛世军,郭向红,孙西欢等.土壤侵蚀模型研究进展[J].山西水利,2008,2:44-45.
[89]张宪奎,许靖华,卢秀琴等.黑龙江省土壤流失方程的研究[J].水土保持通报,1992,12 (4):1-9。
[90]林素兰,黄毅,聂振刚等.辽北低山丘陵区坡耕地土壤流失方程的建立[J].土壤通报,1997,28 (6):251-253.
[91]杨子生.滇东北山区坡耕地土壤侵蚀的作物经营因子[J].山地学报,1999,17 (增):19-21.
[92]于东升,史学正,吕喜玺.低丘红壤区不同土地利用方式C值及可持续性评价[J].土壤侵蚀与水土保持学报,1998,4 (1): 71-76.
[93]张岩,刘宝元,史培军等.黄土高原土壤侵蚀作物覆盖因子计算[J].生态学报,2001,21(7):1050-1056.
[94]张雪花,侯文志,王宁.东北黑土区土壤侵蚀模型中植被因子C值的研究[J].农业环境科学学报,2006,25(3):797-801.
[95]江忠善,郑粉莉,武敏.中国坡面水蚀预报模型研究[J].泥沙研究,2005,(4):1-6.
[96]刘秉正,刘世海,郑随定.作物植被的保土作用及作用系数[J].水土保持研究,1999,6(2):32-36.
[97]张兴昌,卢宗凡.农作物水土保持效益的数值化综合评价[J].水土保持学报,1993,7(2):51-56.
[98]张兴昌,邵明安,黄占斌等.不同植被对土壤侵蚀和氮素流失的影响[J].生态学报,2000,20(6):1038-1043.
[99]孙飞达,蒋志荣,王立.不同降雨强度下农地的产流产沙研究[J].甘肃科学学报,2005,17(1):53-56.
[100]孙飞达,王立,龙瑞军等.黄土丘陵区不同降雨强度对农地土壤侵蚀的影响[J].水土保持研究,2007,14(2):16-18.
[101]邵明安,张兴昌.坡面土壤养分与降雨、径流相互作用机理及模型[J].世界科技研究与发展,2001,23(2):7-12.
[102]Hubbard R. K.,Erickson A. E.,Ellis B. G. et al.. Movement of diffuse source pollutants in small agricultural watersheds of the Great Lakes Basin[J]. Journal of Environmental Quality,1982,11:117-123.
[103]彭琳,王继增,卢宗藩.黄土高原旱作土壤养分剖面运行与坡面流失的研究[J].西北农业学报,1994,3(1):62-66.
[104]刘秉正,李光录,吴发启等.黄土高原南部土壤养分流失规律[J].水土保持学报,1995,9(2):77-86.
[105]康玲玲,朱小勇,王云璋等.不同雨强条件下黄土性土壤养分流失规律研究[J].土壤学报,1999,36(4):536-543.
[106]傅涛,倪九派,魏朝富等.不同雨强和坡度条件下紫色土养分流失规律研究[J].植物营养与肥料学报,2003,9(1):71-74.
[107]马琨,陈欣,王兆骞.模拟暴雨下红壤坡面产流产沙及养分流失特征研究[J].宁夏农学院学报,2004,25(1):1-4.
[108]张亚丽,张兴昌,邵明安等.降雨强度对黄土坡面矿质氮素流失的影响[J].农业工程学报,2004,20(3):55-58.
[109]李艳梅,袁霞,张亚丽等.黄绵土坡面土壤矿质氮素径流流失与入渗特征研究[J].农业环境科学学报,2007,26(1):246-251.
[110]张亚丽,李怀恩,张兴昌等.坡度对坡面土壤矿质氮素水蚀流失负荷的影响[J].水土保持通报,2007,27(2):14-17.
[111]中国科学院黄土高原综合科学考察队.黄土高原地区土壤资源及其合理利用[M].北京:中国科学技术出版社,1991.
[112]袁东海,王兆骞,陈欣等.不同农作方式红壤坡耕地土壤氮素流失特征[J].应用生态学报,2002,13(7):863-866.
[113]陈欣,姜曙千,张克中.红壤坡地磷素流失规律及其影响因素[J].土壤侵蚀与水土保持学报,1999,5(3):38-41.
[114]陈欣,王兆骞,杨武德等.红壤小流域坡地不同利用方式对土壤磷素流失的影响[J].生态学报,2000,20(3):374-377.
[115]李宪文,史学正,Ritsema C..四川紫色土区土壤养分径流和泥沙流失特征研究[J].资源科学,2002,24(6):22-28.
[116]李勇,王超,汤红亮.小流域坡地表土层营养物质输运规律研究进展[J].河海大学学报(自然科学版),2004,32(6):627-631.
[117]李庆召,王定勇,朱波等.川中紫色土旱坡地磷素的输出特征研究[J].水土保持学报,2004,18(6):97-99.
[118]崔力拓,李志伟.洋河流域缓坡地土壤磷素径流输出特征[J].土壤通报,2006,37(6):1199-1202.
[119]李裕元,邵明安,郑纪勇等.降雨强度对黄绵土坡地磷流失特征影响试验研究[J].农业工程学报,2007,23(4):39-45.
[120]杨丽霞,杨桂山,苑韶峰等.不同雨强条件下太湖流域典型蔬菜地土壤磷素的径流特征[J].环境科学,2007,28(8):1763-1769.
[121]李德荣,董闻达,王锋尖等.红壤坡地果园不同水土保持措施对磷素流失的影响[J].水土保持学报,2004,18(4):81-84.
[122]马琨,王兆骞,陈欣.红壤坡面产流产沙与养分流失特征研究[J].宁夏农学院学报,2003,24(2):3-7.
[123]李裕元,邵明安,郑纪勇等.黄绵土坡耕地磷素迁移与土壤退化研究[J].水土保持学报,2003,17(4):1-7.
[124]阎百兴,汤洁.黑土侵蚀速率及其对土壤质量的影响[J].地理研究,2005,24(4):499-506.
[125]孔刚,王全九,樊军.坡度对黄土坡面养分流失的影响实验研究[J].水土保持学报,2007,21(3):14-18.
[126]王辉,王全九,邵明安.人工降雨条件下黄土坡面养分随径流迁移试验[J].农业工程学报,2006,22(6):39-44.
[127]王百群,刘国斌.黄土丘陵区地形对坡地土壤养分流失的影响[J].土壤侵蚀与水土保持学报,1999,5(2):18-22.
[128]王辉,王全九,邵明安.表层土壤容重对黄土坡面养分随径流迁移的影响[J].水土保持学报,2007,21(3):10-13.
[129]孟庆华,傅伯杰,邱扬.黄土丘陵沟壑区不同土地利用方式的径流与磷流失研究[J].自然科学进展,2002,12(4):393-397.
[130]张燕,张洪,彭补拙等.不同土地利用方式下农地土壤侵蚀与养分流失[J].水土保持通报,2003,23(1):23-26.
[131]舒英格,刘方,何腾兵等.不同土壤磷素水平下黄壤旱坡地磷素流失分析[J].耕作与栽培,2002,2:36-38.
[132]Hargrave A. P.,Shaykewich C. F.. Rainfall induced nitrogen and phosphorus losses from Manitoba soils[J]. Canadian Journal of Soil Science,1997,77:59-65.
[133]Wendt R. C.,Corey R. B.. Phosphorus variations in surface runoff from agricultural lands as a function of land use[J]. Journal of Environmental Quality,1980,9:130-136.
[134]徐祖信.河流污染治理技术与实践[M].北京:中国水利水电出版社,2003.
[135]杨陵区地方志编纂委员会.杨陵区志[M].西安:西安地图出版社,2004.
[136]蔡一林,何晓阳.玉米叶面积分布及估测[J].西南农业大学学报,1994,16(1):63-65.
[137]冯冬霞,施生锦.叶面积测定方法的研究效果初报[J].中国农学通报,2005,21(6):150-152.
[138]卫新菊,贾志宽.施肥对苜蓿现蕾期叶面积及比叶重的影响[J].中国农学通报,2007,23(5):10-13.
[139]窦葆璋,周佩华.雨滴的观测和计算方法[J].水土保持通报,1982,1:44-47.
[140]鲍士旦.土壤农化分析[M].北京:中国农业出版社,2005.
[141]陈文亮,王占礼.人工模拟降雨特性的试验研究[J].水土保持通报,1991,11(2):55-62.
[142]牟金泽.雨滴速度计算公式[J].中国水土保持,1983,3:40-41.