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Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

Science china Earth Sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3, ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The key laboratory of Modern Precision Agriculture System Integration Research, College of Hydraulic and Civil Engineer-ing,{2. Agricultural University, Beijing 100083,{2. 2. state key laboratory of soil erosion and dryland farming on the loess plateau, institute of soil and water conservation, yangling 712100,{2. 3. Geographic and Resources Management College, Yantai Normal University, Yantai 2.402.,{2. The key laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing China state key {2. of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation Yangling China Geographic and Resources Management College Yantai Normal University Yantai China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.39% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

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Using soil surface gray level to determine surface soil {2. content

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Science china Earth Sciences 2010年第10期53卷 1527-1532页

作者： ZHU YuanJun1,2.WANG YunQiang1,2.& SHAO MingAn1,2.1 state key {2. of soil erosion and dryland farming on loess plateau,institute of soil and water {12.,Northwest A & F University,yangling 712100,china 2.16},Chinese Academy of Sciences & Ministry of water Resources,yangling 712100,china state key {2. of soil erosion and dryland farming on loess plateau Institute of Soil and Water Conservation Northwest A & F University Yangling China institute of soil and {2. conservation Chinese Academy of Sciences & Ministry of Water Resources Yangling China

How to determine surface soil water content(SWC) quickly and accurately is fundamental in studying eco-hydrological processes and their *** we use {2. experiments to determine surface SWC using soil surface gray level(SGL) values.A negatively exponential relationship exists between SGL and SWC,i.e.,SGL increases with the decrease of *** can be estimated based on initial SGL value(surface gray level when SWC=0),SWC,and a surface roughness coefficient characterized by mean soil particle *** variation range of SGL was larger than that of SWC,indicating that changes in SWC were enhanced in SGL,and that SGL would thus be sensitive to changes in soil *** the 95% confidence level,SWC can be determined by using the relationship between SWC and SGL established by the *** determination of SWC has a high precision when SWC was between dry and saturated.

关键词： loess plateau soil water remote sensing surface roughness

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Nitrate Accumulation in soil Profile of Dry Land farming in Northwest{2.

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Pedosphere 2003年第4期13卷 367-374页

作者： FAN Jun, HAO Ming-De and SHAO Ming-Anstate key {2. of soil erosion and dryland farming on the loess plateau, institute of soil and water conservation, the Chinese Academy of Sciences, yangling 712100 (china). institute of soil and {2. conservation the Chinese Academy of Sciences State Key Labamlory of Sail Erosion and Dryland Farming on the Loess Plateau Yanyhng 712100

A long-term fertilizer experiment on dry land of the loess plateau, northwest{2., has been conducted since 1984 to study the distribution and accumulation of NO_3-N down to adepth of 400 cm in the profile of a coarse-textured dark loessial soilafter continuous winter wheatcropping. Thirteen fertilizer treatments consisted of four levels of N and P applied alone or incombination. Annual N and P (P_2._5) rates were 0, 45, 90, 135 and 180 kg ha^(-1). After 15successive cropping cycles, the soil samples were taken from each treatment for analysis of NO_3-Nconcentration. The results showed that NO_3-N distribution in the soil profile was quite differentamong the treatments. The application of fertilizer N alone resulted in higher NO_3-N concentrationin the soil profile than the combined application of N and P, showing that application of P couldgreatly reduce the NO_3-N accumulation. With an annual application of 180 kg N ha^(-1) alone, a peakin NO_3-N accumulation occurred at 140 cm soildepth, and the maximum NO_3-N concentration in thesoils was 67.92.mg kg^(-1). The amount of NO_3-N accumulated in the soil profile decreased as thecumulative N uptake by the winter wheat increased. Application of a large amount of N resulted inlowerN recoveries in winter wheat and greater NO_3-N accumulation in soil profile. KO_3-N did notenter underground {12. in the study region; therefore, there is no danger of underground {12.pollution. Amount of NO_3-N accumulation can be predicted by an equation according to annual N and Prates based on the results of this experiment.

关键词： dry land long-term fertilizer experiment NO_3-N accumulation wheat

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Effect of Ryegrasses on soil Runoff and Sediment Control

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Pedosphere 2008年第1期18卷 131-136页

作者： ZHOU Zheng-Chao SHANGGUAN Zhou-Ping College of Tourism and Environmental Sciences Shaanxi Normal University Xi'an 710062 (China) state key {2. of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling Shaanxi 712100 (China) Northwest A & F University Yangling Shaanxi 712100 (China)

Living plants and plant roots can reduce runoff and soil erosion. Using a rain simulator, a series of soil erosion experiments were conducted to study the influence of living roots and canopies of ryegrasses （Lolium perenne L.） during the growing season on sediment yields and runoff of a silt loam soil. The results indicated that during the growing season, decrements in runoff and sediment yields increased with time. Sediment yields （τ^2.= 0.999） and decrements in runoff （τ2.= 0.946） were closely related to the root surface area density. The contributions of roots and canopies of ryegrasses to the reductions in runoff and sediment yields were different. Canopies usually contributed more to the runoff decrement than the roots, whereas roots contributed up to 96% of the decrease in sediment yields in the late stage of the growing season.

关键词： canopy root runoff ryegrass sediment yield

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Behaviours of soil-Root Interface and Their Variations with Wheat Varieties

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Pedosphere 1997年第2期7卷 133-140页

作者： HUANG MINGBIN KANG SHAOZHONG ZHANG FUCANG and LI YUSHAN(state key {2. of soil erosion and dryland farming on loess plateau, institute of soil and water{12., Academia Sinica and Mnistry of water Resoumes, Shaanxi, yangling 712100 (china))(N state key {2. of soil erosion and dryland farming on loess plateau Institute of Soil and Water Conservation Academia Sinica and Ministry of Water Resources Shaanxi Yangling 71S100 China Northwestern Agricultural University Shaanxi Yangling 71S100 China

water movement into and out of roots depends on the water potential difference between the bulk {2.and the root xylem and the total hydraulic conductance of the pathway, which can be divided into three parts,i.e. {2. conductance, {2.-root conductance and root conductance. The vaues and relative importance varywith {2. water content. The general rule is that water uptake by roots is mainly limited by radial hydraulicconductance of roots in wet {2.s, the {2.-root interfaCe becomes a major limiting factor to water uptake inmoderately dry {2.s, and the water uptake is limited by the rapidly decreasing {2. hydraulic conductance inseriously dry {2.s. Meanwhile these limiting factors vary with crop variety, and these variations can be usedto evaluate the drought-resistance and water use efficiency of crops.

关键词： crop variety hydraulic resistance soil-root interface

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Crop Yield Response to water and Fertilizer in loess Tableland of {2.：A Field Research

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Pedosphere 1995年第3期5卷 259-266页

作者： LIU WEN-ZHAO and LI YU-SHAN(state key {2. of soil Erusion and dryland farming on loess plateau, Northwest institute of soiland water conservation, Chinese Academy of Sciences,{12. (china) )

This paper describes a field research on crop yield response to water and fertilizer in Changwu tablelandof the loess {2.. Under the current level of land management in this areai low fertility of soil is thefirst yield-limiting factor and water deficit is the second. At a given fertility level, the relationship betweencrop yield and its water consumption is parabolic. Within a certain range of soil moisture, the soil wateravailability to crop is not sharply decreased with its markedly decreasing content. Because of this relativelyhigh availability and the high reserve of soil water at the early stage of crop growth, drought due to inadequateor poorly distributed rainfall becomes less serious. High fertilizer input, improved crop variety and optimumcnltivation techniqne can give a 50-100% yield increment of dryland crops in the loess tableland.

关键词： grain yield loess plateau soil fertility soil moisture

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Wheat Grain Yield and Yield Stability in a Long-Term Fertilization Experiment on the loess plateau

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Pedosphere 2007年第2期17卷 257-264页

作者： HAO Ming-De FAN Jun WANG Quan-Jiu DANG Ting-Hui GUO Sheng-Li WANG Ji-Jun institute of soil and {2. conservation Chinese Academy of Sciences Yangling 712100 （China）. state key {2. of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 （China） Northwest A ＆ F University Yangling 712100 （China）

To provide a scientific basis for sustainable land management, a 2.-year fertility experiment was conducted in Changwu County, Shaanxi Province, china to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the loess {2. using regression and stability analysis. The experiment consisted of 17 fertilizer treatments, containing the combinations of different N and P levels, with three replications arranged in a randomized complete block design. Nitrogen fertilizer was applied as urea, and P was applied as calcium superphosphate. Fertilizer rates had a large effect on the response of wheat yield to fertilization. Phosphorus, combined with N, increased yield significantly （P 〈 0.01）. In the unfertilized control and the N or P sole application treatments, wheat yield had a declining trend although it was not statistically significant. Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.

关键词： dryland wheat yield long-term fertilization nitrogen phosphorus yield stability

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Ecological Reconstruction of the loess plateau and Research of {2. erosion and dryland Agriculture

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西北植物学报 2001年第6期 8-10页

作者： SHAO Ming an SHANGGUAN Zhou ping (state key {2. of soil erosion and dryland Agriculture on the loess plateau institute of soil and water conservation,Chinese Academy of Sciences and Ministry of water Resources,yangling,Shaanxi,712100)

It is a very important aspect of strategies for West china Development and sustainable agriculture and economy in this area to get soil and {2. conservation well done and to concentrate on the construction of the ecological environment in West *** main issue of the National laboratory of soil erosion and dryland Agriculture on the loess plateau is to deal with soil erosion control and to increase productivity of dryland farming in this area. This laboratory pays its great attention to applied fundamental research and key technologies for the environmental construction and dryland agriculture in the loess *** state and Ministrys projects,together with collaboration with famous research organizations and universities in the world,important progresses have been achieved in mechanics of soil erosion,eroded soil quality,soil {2. movement and solute transport,biological basis of {2.-saving agriculture,hydrological effect of a small {2.shed,and so on. The progresses are very useful and valuable to ecological and environmental construction for West *** laboratory provides important recommendations to central and local governments for environmental construction and science and technology for soil erosion control and dryland agriculture in the loess plateau.

关键词： soil erosion drylang agriculture loess plateau ecological environment

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Quantitative analysis of soil pores under natural vegetation successions on the loess {2.

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Science china Earth Sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2.& WU JinShui3 1 state key {2. of soil erosion and dryland farming on the loess plateau,institute of soil and water {12.,Northwest Agriculture & Forestry University,yangling 712100,china 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3 institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 41012.,china state key {2. of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling China Graduate University of Chinese Academy of Sciences Beijing China institute of Subtropical Agriculture Chinese Academy of Sciences Changsha China

soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(Psoil pore characteristics in natural vegetation succession.

关键词： Computed Tomography loess plateau natural vegetation succession soil pore soil organic matter

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Inorganic Phosphorus Fractions and Phosphorus Availability in a Calcareous soil Receiving 2.-Year Superphosphate Application

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Pedosphere 2010年第3期20卷 304-310页

作者： WANG Jun LIU Wen-Zhao MU Han-Feng DANG Ting-Hui state key {2. of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conser-vation Northwest A&F University Yangling 712100 (China) College of Urban and Environment Northwest University Xi'an 710127 (China)

A long-term （2.-year） field experiment was performed to study the responses of soil inorganic P fractions and P availability to annual fertilizer P application in a calcareous soil on the {2. plateau of china. soil Olsen-P contents increased by 3.7, 5.2. 11.2.and 2..6 mg P kg-1 after 2.-year annual fertilizer P application at 2., 39, 59, and 79 kg P ha-1, respectively. Long-term fertilizer P addition also increased soil total P and inorganic P （Pi） contents significantly. The contents of inorganic P fractions were in the order of Ca10-P 〉 Cas-P 〉 Fe-P 〉 A1-P 〉 occluded P 〉 Ca2.P in the soil receiving annual fertilizer P application. Fertilizer P application increased Cas-P, A1-P and Ca2.P contents as well as their percentages relative to Pi. Pi application increased Fe-P and occluded P contents but nor their percentages. soil Ca10- P content remained unchanged after fertilizer P application while its percentage relative to Pi declined with increasing fertilizer P rate. All Pi fractions but Ca10-P were correlated with Olsen-P significantly. 90% of variations in Olsen-P could be explained by Pi fractions, and the direct contribution of Cas-P was predominant. Long-term annual superphosphate application would facilitate the accumulation of soil Cas-P, and thus improve soil P availability.

关键词： long-term experiment Olsen-P path analysis loess plateau

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