陕西不同区域苹果林土壤水分动态和水分生产力模拟
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摘要
基于WinEPIC和偏最小二乘回归模型对1981—2016年陕西不同区域成龄苹果林的水分生产力影响因子和土壤水分动态进行比较.结果表明:研究期间,陕北丘陵沟壑区、渭北残塬区和关中平原区成龄苹果林年均产量分别为16.94、22.62和25.70 t·hm~(-2),年均蒸散量分别为511.2、614.9和889.88 mm,水分生产力分别为3.81、3.82和3.24 kg·m~(-3).在陕北区和渭北区,林地水分胁迫最严重,年均胁迫天数分别为54.89、28.38 d,关中区的N素胁迫较为剧烈,年均胁迫天数为25.87 d.陕北区和渭北区影响苹果林产量的最大因子是降水量,其标准化回归系数分别为0.274和0.235,但施N量对产量也有较大影响,回归系数分别达0.224和0.232;关中区的最大影响因子为施N量,回归系数为0.335,其次是供水量和施P量,回归系数分别为0.154和0.147.陕北区和渭北区影响苹果林水分生产力的最大因子是降水量,其标准化回归系数分别0.238和0.194;关中区最主要的影响因子为施N量和供水量,回归系数分别为0.182和0.178.在模拟期间,陕北区、渭北区和关中区苹果林地的过耗水总量分别为1152.17、1342.95和1372.42 mm,2～15 m土层土壤有效含水量下降速率分别为63.44、57.08、51.41 mm·a~(-1),深层土壤干层出现时间分别为8、13和17年后,干层稳定至11 m深的时间分别为18、21和26年,干燥化严重.不同区域苹果林的管理重心应参考水分生产力的主导因子确定.
Using WinEPIC and partial least squares regression model,we compared the driving factors of water productivity and soil moisture dynamics of several mature apple plantations in Shaanxi from 1981 to 2016. For the hilly and gully region of northern Shaanxi,the residual loess platform region in Weibei,and Guanzhong Plain,the average annual yield of mature apple forests was 16.94,22.62 and 25. 70 t · hm~(-2),the annual average evapotranspiration was 511.2,614.9 and 889.88 mm,and the water productivity was 3. 81,3. 82 and 3. 24 kg · m~(-3),respectively. In northern Shaanxi and Weibei regions,water stress was the most serious,with the average annual stress days being 54.89 and 28.38 d,respectively. The N-level stress in Guanzhong region was severe,with an average annual stress day of 25.87 d. The largest factor affecting the yield of apple plantations in the northern Shaanxi and northern Weibei regions was the precipitation. The standardized regression coefficients were 0.274 and 0.235,respectively,the amount of N applied had a significant impact on the yield,with regression coefficients of 0. 224 and 0. 232,respectively. The maximum impact factor in Guanzhong region was the amount of N applied,with a regression coefficient of 0.335,followed by the amount of water supplied and the amount of applied P. The regression coefficients were0.154 and 0.147,respectively. The dominant factor affecting the water productivity of apple plantations in northern Shaanxi and Weibei was precipitation,and the standardized regression coefficients were 0.238 and 0.194,respectively. The most important impact factors in Guanzhong region were the amount of N applied and the amount of water supplied,and the regression coefficients were0.182 and 0.178,respectively. During the simulation period,the total water consumption of apple plantations in the northern Shaanxi,Weibei and Guanzhong regions was 1152. 17,1342. 95 and1372.42 mm,respectively. The effective water content decline rates of 2-15 m soil layers were63.44,57.08 and 51.41 mm·a~(-1),respectively. The dry layer of deep soil appeared after 8,13 and17 years,and the dry layer was stable to 11 m deep for 18,21 and 26 years,respectively,suggesting the drying status was severe. The management focus of apple plantations in different regions should be determined by the dominant factors of water productivity.
Using WinEPIC and partial least squares regression model,we compared the driving factors of water productivity and soil moisture dynamics of several mature apple plantations in Shaanxi from 1981 to 2016. For the hilly and gully region of northern Shaanxi,the residual loess platform region in Weibei,and Guanzhong Plain,the average annual yield of mature apple forests was 16.94,22.62 and 25. 70 t · hm~(-2),the annual average evapotranspiration was 511.2,614.9 and 889.88 mm,and the water productivity was 3. 81,3. 82 and 3. 24 kg · m~(-3),respectively. In northern Shaanxi and Weibei regions,water stress was the most serious,with the average annual stress days being 54.89 and 28.38 d,respectively. The N-level stress in Guanzhong region was severe,with an average annual stress day of 25.87 d. The largest factor affecting the yield of apple plantations in the northern Shaanxi and northern Weibei regions was the precipitation. The standardized regression coefficients were 0.274 and 0.235,respectively,the amount of N applied had a significant impact on the yield,with regression coefficients of 0. 224 and 0. 232,respectively. The maximum impact factor in Guanzhong region was the amount of N applied,with a regression coefficient of 0.335,followed by the amount of water supplied and the amount of applied P. The regression coefficients were0.154 and 0.147,respectively. The dominant factor affecting the water productivity of apple plantations in northern Shaanxi and Weibei was precipitation,and the standardized regression coefficients were 0.238 and 0.194,respectively. The most important impact factors in Guanzhong region were the amount of N applied and the amount of water supplied,and the regression coefficients were0.182 and 0.178,respectively. During the simulation period,the total water consumption of apple plantations in the northern Shaanxi,Weibei and Guanzhong regions was 1152. 17,1342. 95 and1372.42 mm,respectively. The effective water content decline rates of 2-15 m soil layers were63.44,57.08 and 51.41 mm·a~(-1),respectively. The dry layer of deep soil appeared after 8,13 and17 years,and the dry layer was stable to 11 m deep for 18,21 and 26 years,respectively,suggesting the drying status was severe. The management focus of apple plantations in different regions should be determined by the dominant factors of water productivity.
引文
[1] Demestihas C,Plenet D,Genard M,et al. Ecosystem services in orchards:A review. Agronomy for Sustainable Development, 2017, 37:12. DOI:10. 1007/s13593-017-0422-1
[2] National Bureau of Statistics of China(国家统计局).China Statistical Yearbook 2017. Beijing:China Statistics Press,2017(in Chinese)
[3] Li Y-S(李玉山). Impact of soil and water conservation control on land water cycle. Bulletin of Soil and Water Conservation(水土保持通报),2014,34(5):2-3(in Chinese)
[4] Yang W-Z(杨文治),Yu C-Z(余存祖). Regional Governance and Evaluation of the Loess Plateau. Beijing:Science Press,1992(in Chinese)
[5] Lauer MJ,Boyer JS. Internal CO2measured directly in leaves-abscisic-acid and low leaf water potential cause opposing effects. Plant Physiology,1992,98:1310-1316
[6] Tomlinson KW,Sterck FJ,Bongers F,et al. Biomass partitioning and root morphology of savanna trees across a water gradient. Journal of Ecology, 2012, 100:1113-1121
[7] Alam SA,Huang JG,Stadt KJ,et al. Effects of competition,drought stress and photosynthetic productivity on the radial growth of white spruce in western Canada.Frontiers in Plant Science,2017,8:1915,doi:10.3389/fpls.2017.01915
[8] Ryan MG. Tree responses to drought. Tree Physiology,2011,31:237-239
[9] Shan L(山仑),Xu M(徐萌). Water-saving agriculture and its physiological and ecological basis.Chinese Journal of Applied Ecology(应用生态学报),1991,2(1):70-76(in Chinese)
[10] Liu JG. A GIS-based tool for modeling large-scale cropwater relations. Environmental Modelling&Software,2009,24:411-422
[11] Ali MH,Talukder MSU. Increasing water productivity in crop production:A synthesis. Agricultural Water Management,2008,95:1201-1213
[12] Sonia IS,Thierry C,Edouard LD,et al. Investigating soil moisture-climate interactions in a changing climate:A review. Earth-Science Reviews,2010,99:125-161
[13] Lin Z-H(林忠辉),Mo X-G(莫兴国),Xiang Y-Q(项月琴). Summary of research on crop growth model.Acta Agronomica Sinica(作物学报),2003,29(5):750-758(in Chinese)
[14] Fan L(范兰),Lyu C-H(吕昌河),Chen C(陈朝). A review of EPIC model and its applications. Progress in Geography(地理科学进展),2012,32(5):584-592(in Chinese)
[15] Niu XZ,Easterling W,Hays CJ,et al. Reliability and input-data induced uncertainty of the EPIC model to estimate climate change impact on sorghum yields in the U.S. Great Plains. Agriculture,Ecosystems and Environment,2009,129:268-276
[16] Qiao JM,Yu DY,Wu JG. How do climatic and management factors affect agricultural ecosystem services? A case study in the agro-pastoral transitional zone of northern China. Science of the Total Environment,2018,613/614:314-323
[17] Wang XC,Li J,Muhammad NT,et al. Validation of the EPIC model using a long-term experimental data on the semi-arid Loess Plateau of China. Mathematical and Computer Modeling,2011,54:976-986
[18] Zhang S-H(张社红),Li J(李军),Wang X-C(王学春),et al. Modeling the changes of yield and deep soil water in apple orchards in Weibei rain-fed highland.Acta Ecologica Sinica(生态学报),2011,31(13):3767-3777(in Chinese)
[19] Fan P(范鹏),Li J(李军),Zhang L-N(张丽娜),et al. Dynamic simulation of apple yield and dynamic response of deep soil moisture under rain-fed apple orchards of different planting densities at Baoji.Chinese Journal of Eco-Agriculture(中国生态农业学报),2013,21(11):1377-1385(in Chinese)
[20] Guo Z(郭正),Li J(李军),Zhang Y-J(张玉娇). Simulation and comparison of water productivity and soil desiccation effects of apple orchards in different rainfall regions of the Loess Plateau. Journal of Natural Resources(自然资源学报),2016,31(1):135-150(in Chinese)
[21] Williams JR,Jones CA,Dyke PT. A modeling approach to determining the relationship between erosion and soil productivity. Transactions of the American Society of Agricultural and Biological Engineers,1984,27:129-144
[22] Sharple AN,Williams JR. EPIC-Erosion/productivity Impact Calculator:1. Model Documentation. US Department of Agriculture Technology Bulletin No. 1768,1990
[23] Williams JR,Jones CA,Kiniry JR,et al. The EPIC crop growth model. Transaction of American Society of Agricultural and Biological Engineers,1989,32:475-511
[24] Benson V,Potter K,Bogusch H,et al. Nitrogen leaching sensitivity to evapotranspiration and soil water storage estimates in EPIC. Journal of Soil&Water Conservation,1992,47:334-337
[25] Chavas DR,Izaurralde RC,Thomson AM,et al. Longterm climate change impacts on agricultural productivity in eastern China. Agricultural and Forest Meteorology,2009,149:1118-1128
[26] Monteith J. Resistance of a partially wet canopy:Whose equation fails? Boundary:Layer Meteorology,1977,12:379-383
[27] Allen RG,Pereira LS,Raes D,et al. Crop Evapotranspiration:Guidelines for Computing Crop Water Requirements. FAO Irrigation and Drainage Paper 56. Rome:FAO,1998
[28] Li J(李军),Shao M-A(邵明安),Zhang X-C(张兴昌). Simulation equations for soil water transfer and use in the EPIC model. Agricultural Research in the Arid Areas(干旱地区农业研究),2004,22(2):72-75(in Chinese)
[29] BREC. Weather Import User Manual and Executable File[EB/OL].(2014-12-12)[2016-02-03]. http://epicapex.tamu.edu/model-executables/weather-import/
[30] Zuo D-K(左大康),Wang Y-X(王懿贤),Chen J-S(陈建绥). Spatial distribution characteristics of total solar radiation in China. Acta Meteorologica Sinica(气象学报),1963,33(2):78-95(in Chinese)
[31] Li J(李军),Shao M-A(邵明安),Zhang X-C(张兴昌). Database construction for the EPIC model on the Loess Plateau region. Journal of Northwest A&F University(Natural Science)(西北农林科技大学学报:自然科学版),2004,32(8):21-26(in Chinese)
[32] Ma T-S(马同生). Chinese Soil Species,Vol. 6. Beijing:Chinese Agriculture Press,1996(in Chinese)
[33] Shaanxi Province Soil Survey and Investigation Office(陕西省土壤普查办公室). Shaanxi Soil. Beijing:Science Press,1992(in Chinese)
[34] Wang X-Y(王小英),Tong Y-P(同延平),Liu F(刘芬). Evaluation of the situation of fertilization in apple fields in Shaanxi province. Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2013,19(1):206-213(in Chinese)
[35] Lu Q-N(陆秋农),Jia D-X(贾定贤). Chinese Fruit Tree(Apple Roll). Beijing:China Forestry Press,1999(in Chinese)
[36] Wang H-W(王惠文),Wu Z-B(吴载斌),Meng J(孟洁). Partial Least-Squares Regression-Linear and Nonlinear Methods. Beijing:National Defense Industry Press,2006(in Chinese)
[37] Zhang H-X(张恒喜),Guo J-L(郭基联),Zhu J-Y(朱家元). Multivariate Data Analysis Methods and Applications. Xi’an:Northwestern Polytechnical University Press,2002(in Chinese)
[38] Ma M-D(马明德),Ma X-J(马学娟),Xi Y-Z(谢应忠),et al. Analysis of the relationship between ecological footprint(EF)of Ningxia and influencing factors:Partial least-squares regression. Acta Ecologica Sinica(生态学报),2014,34(3):682-689(in Chinese)
[39] Saltelli,A,Tarantola S,Saisana M,et al. Sensitivity Analysis. New York:John&Sons,2011
[40] Tao F,Yokozawa M,Liu J,et al. Climate-crop yield relationships at provincial scales in China and the impacts of recent climate trends. Climate Research,2008,38:83-94
[41] Wang Y-P(王延平),Shao M-A(邵明安). Soil water carrying capacity of an apricot forest on Loess Region in Northern Shaanxi. Scientiac Silvae Sinicae(林业科学),2009,45(12):2-7(in Chinese)
[42] Wang L(王力),Shao M-A(邵明安),Zhang Q-F(张青峰). Distribution and differentiation characteristics of dry soil layers in the Loess Plateau of Northern Shaanxi. Chinese Journal of Applied Ecology(应用生态学报)2004,15(3):436-442(in Chinese)
[43] Shao M-A(邵明安),Jia X-X(贾小旭),Wang Y-Q(王云强). Progress and prospects of soil dry layer research in the Loess Plateau. Progress in Geography(地理科学进展),2016,31(1):14-22(in Chinese)
[44] Ran W(冉伟),Xie Y-S(谢永生),Hao M-D(郝明德). Study on change of soil water in orchards of different planting-life in gully region of Loess Plateau. Acta Agriculturae Boreali-Occidentalis Sinica(西北农业学报),2008,17(4):229-233(in Chinese)
[45] Wang Y-P(王延平),Han M-Y(韩明玉),Zhang L-S(张林森),et al. Spatial characteristics of soil moisture of apple orchards in the Loess Plateau of Shaanxi Province. Scientia Silvae Sinicae(林业科学),2013,49(7):16-25(in Chinese)
[46] Li J(李军),Wang X-C(王学春),Shao M-A(邵明安),et al. Simulation of water-limiting biomass productivity of Chinese pine plantations and the soil desiccation effect in 3 sites with different annual precipitation on Loess Plateau. Scientia Silvae Sinicae(林业科学),2010,46(11):25-35(in Chinese)
[2] National Bureau of Statistics of China(国家统计局).China Statistical Yearbook 2017. Beijing:China Statistics Press,2017(in Chinese)
[3] Li Y-S(李玉山). Impact of soil and water conservation control on land water cycle. Bulletin of Soil and Water Conservation(水土保持通报),2014,34(5):2-3(in Chinese)
[4] Yang W-Z(杨文治),Yu C-Z(余存祖). Regional Governance and Evaluation of the Loess Plateau. Beijing:Science Press,1992(in Chinese)
[5] Lauer MJ,Boyer JS. Internal CO2measured directly in leaves-abscisic-acid and low leaf water potential cause opposing effects. Plant Physiology,1992,98:1310-1316
[6] Tomlinson KW,Sterck FJ,Bongers F,et al. Biomass partitioning and root morphology of savanna trees across a water gradient. Journal of Ecology, 2012, 100:1113-1121
[7] Alam SA,Huang JG,Stadt KJ,et al. Effects of competition,drought stress and photosynthetic productivity on the radial growth of white spruce in western Canada.Frontiers in Plant Science,2017,8:1915,doi:10.3389/fpls.2017.01915
[8] Ryan MG. Tree responses to drought. Tree Physiology,2011,31:237-239
[9] Shan L(山仑),Xu M(徐萌). Water-saving agriculture and its physiological and ecological basis.Chinese Journal of Applied Ecology(应用生态学报),1991,2(1):70-76(in Chinese)
[10] Liu JG. A GIS-based tool for modeling large-scale cropwater relations. Environmental Modelling&Software,2009,24:411-422
[11] Ali MH,Talukder MSU. Increasing water productivity in crop production:A synthesis. Agricultural Water Management,2008,95:1201-1213
[12] Sonia IS,Thierry C,Edouard LD,et al. Investigating soil moisture-climate interactions in a changing climate:A review. Earth-Science Reviews,2010,99:125-161
[13] Lin Z-H(林忠辉),Mo X-G(莫兴国),Xiang Y-Q(项月琴). Summary of research on crop growth model.Acta Agronomica Sinica(作物学报),2003,29(5):750-758(in Chinese)
[14] Fan L(范兰),Lyu C-H(吕昌河),Chen C(陈朝). A review of EPIC model and its applications. Progress in Geography(地理科学进展),2012,32(5):584-592(in Chinese)
[15] Niu XZ,Easterling W,Hays CJ,et al. Reliability and input-data induced uncertainty of the EPIC model to estimate climate change impact on sorghum yields in the U.S. Great Plains. Agriculture,Ecosystems and Environment,2009,129:268-276
[16] Qiao JM,Yu DY,Wu JG. How do climatic and management factors affect agricultural ecosystem services? A case study in the agro-pastoral transitional zone of northern China. Science of the Total Environment,2018,613/614:314-323
[17] Wang XC,Li J,Muhammad NT,et al. Validation of the EPIC model using a long-term experimental data on the semi-arid Loess Plateau of China. Mathematical and Computer Modeling,2011,54:976-986
[18] Zhang S-H(张社红),Li J(李军),Wang X-C(王学春),et al. Modeling the changes of yield and deep soil water in apple orchards in Weibei rain-fed highland.Acta Ecologica Sinica(生态学报),2011,31(13):3767-3777(in Chinese)
[19] Fan P(范鹏),Li J(李军),Zhang L-N(张丽娜),et al. Dynamic simulation of apple yield and dynamic response of deep soil moisture under rain-fed apple orchards of different planting densities at Baoji.Chinese Journal of Eco-Agriculture(中国生态农业学报),2013,21(11):1377-1385(in Chinese)
[20] Guo Z(郭正),Li J(李军),Zhang Y-J(张玉娇). Simulation and comparison of water productivity and soil desiccation effects of apple orchards in different rainfall regions of the Loess Plateau. Journal of Natural Resources(自然资源学报),2016,31(1):135-150(in Chinese)
[21] Williams JR,Jones CA,Dyke PT. A modeling approach to determining the relationship between erosion and soil productivity. Transactions of the American Society of Agricultural and Biological Engineers,1984,27:129-144
[22] Sharple AN,Williams JR. EPIC-Erosion/productivity Impact Calculator:1. Model Documentation. US Department of Agriculture Technology Bulletin No. 1768,1990
[23] Williams JR,Jones CA,Kiniry JR,et al. The EPIC crop growth model. Transaction of American Society of Agricultural and Biological Engineers,1989,32:475-511
[24] Benson V,Potter K,Bogusch H,et al. Nitrogen leaching sensitivity to evapotranspiration and soil water storage estimates in EPIC. Journal of Soil&Water Conservation,1992,47:334-337
[25] Chavas DR,Izaurralde RC,Thomson AM,et al. Longterm climate change impacts on agricultural productivity in eastern China. Agricultural and Forest Meteorology,2009,149:1118-1128
[26] Monteith J. Resistance of a partially wet canopy:Whose equation fails? Boundary:Layer Meteorology,1977,12:379-383
[27] Allen RG,Pereira LS,Raes D,et al. Crop Evapotranspiration:Guidelines for Computing Crop Water Requirements. FAO Irrigation and Drainage Paper 56. Rome:FAO,1998
[28] Li J(李军),Shao M-A(邵明安),Zhang X-C(张兴昌). Simulation equations for soil water transfer and use in the EPIC model. Agricultural Research in the Arid Areas(干旱地区农业研究),2004,22(2):72-75(in Chinese)
[29] BREC. Weather Import User Manual and Executable File[EB/OL].(2014-12-12)[2016-02-03]. http://epicapex.tamu.edu/model-executables/weather-import/
[30] Zuo D-K(左大康),Wang Y-X(王懿贤),Chen J-S(陈建绥). Spatial distribution characteristics of total solar radiation in China. Acta Meteorologica Sinica(气象学报),1963,33(2):78-95(in Chinese)
[31] Li J(李军),Shao M-A(邵明安),Zhang X-C(张兴昌). Database construction for the EPIC model on the Loess Plateau region. Journal of Northwest A&F University(Natural Science)(西北农林科技大学学报:自然科学版),2004,32(8):21-26(in Chinese)
[32] Ma T-S(马同生). Chinese Soil Species,Vol. 6. Beijing:Chinese Agriculture Press,1996(in Chinese)
[33] Shaanxi Province Soil Survey and Investigation Office(陕西省土壤普查办公室). Shaanxi Soil. Beijing:Science Press,1992(in Chinese)
[34] Wang X-Y(王小英),Tong Y-P(同延平),Liu F(刘芬). Evaluation of the situation of fertilization in apple fields in Shaanxi province. Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2013,19(1):206-213(in Chinese)
[35] Lu Q-N(陆秋农),Jia D-X(贾定贤). Chinese Fruit Tree(Apple Roll). Beijing:China Forestry Press,1999(in Chinese)
[36] Wang H-W(王惠文),Wu Z-B(吴载斌),Meng J(孟洁). Partial Least-Squares Regression-Linear and Nonlinear Methods. Beijing:National Defense Industry Press,2006(in Chinese)
[37] Zhang H-X(张恒喜),Guo J-L(郭基联),Zhu J-Y(朱家元). Multivariate Data Analysis Methods and Applications. Xi’an:Northwestern Polytechnical University Press,2002(in Chinese)
[38] Ma M-D(马明德),Ma X-J(马学娟),Xi Y-Z(谢应忠),et al. Analysis of the relationship between ecological footprint(EF)of Ningxia and influencing factors:Partial least-squares regression. Acta Ecologica Sinica(生态学报),2014,34(3):682-689(in Chinese)
[39] Saltelli,A,Tarantola S,Saisana M,et al. Sensitivity Analysis. New York:John&Sons,2011
[40] Tao F,Yokozawa M,Liu J,et al. Climate-crop yield relationships at provincial scales in China and the impacts of recent climate trends. Climate Research,2008,38:83-94
[41] Wang Y-P(王延平),Shao M-A(邵明安). Soil water carrying capacity of an apricot forest on Loess Region in Northern Shaanxi. Scientiac Silvae Sinicae(林业科学),2009,45(12):2-7(in Chinese)
[42] Wang L(王力),Shao M-A(邵明安),Zhang Q-F(张青峰). Distribution and differentiation characteristics of dry soil layers in the Loess Plateau of Northern Shaanxi. Chinese Journal of Applied Ecology(应用生态学报)2004,15(3):436-442(in Chinese)
[43] Shao M-A(邵明安),Jia X-X(贾小旭),Wang Y-Q(王云强). Progress and prospects of soil dry layer research in the Loess Plateau. Progress in Geography(地理科学进展),2016,31(1):14-22(in Chinese)
[44] Ran W(冉伟),Xie Y-S(谢永生),Hao M-D(郝明德). Study on change of soil water in orchards of different planting-life in gully region of Loess Plateau. Acta Agriculturae Boreali-Occidentalis Sinica(西北农业学报),2008,17(4):229-233(in Chinese)
[45] Wang Y-P(王延平),Han M-Y(韩明玉),Zhang L-S(张林森),et al. Spatial characteristics of soil moisture of apple orchards in the Loess Plateau of Shaanxi Province. Scientia Silvae Sinicae(林业科学),2013,49(7):16-25(in Chinese)
[46] Li J(李军),Wang X-C(王学春),Shao M-A(邵明安),et al. Simulation of water-limiting biomass productivity of Chinese pine plantations and the soil desiccation effect in 3 sites with different annual precipitation on Loess Plateau. Scientia Silvae Sinicae(林业科学),2010,46(11):25-35(in Chinese)