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Joint Multifractal Analysis of Scaling Relationships Between soil water-Retention Parameters and soil Texture

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Pedosphere 2011年第3期21卷 373-379页

作者： WANG Zheng-Ying SHU Qiao-Sheng XIE Li-Ya LIU Zuo-Xin B. C. SI Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 (China) Graduate University of Chinese Academy of Sciences Beijing 100039 (China) liaoning Institute of soil and water conservation Chaoyang 122000 (China) Department of soil Science University of Saskatchewan Saskatoon SK STN 5A8 (Canada)

soil water-retention characteristics at measurement scales are generally different from those at application scales, and there is scale disparity between them and soil physical properties. The relationships between two water-retention parameters, the scaling parameter related to the inverse of the air-entry pressure （avG, cm- 1） and the curve shape factor related to soil pore-size distribution （n） of the van Genuchten water-retention equation, and soil texture （sand, silt, and clay contents） were examined at multiple scales. One hundred twenty-eight undisturbed soil samples were collected from a 640-m transect located in Fuxin, China. soil water-retention curves were measured and the van Genuchten parameters were obtained by curve fitting. The relationships between the two parameters and soil texture at the observed scale and at multiple scales were evaluated using Pearson correlation and joint multifractal analyses, respectively. The results of Pearson correlation analysis showed that the parameter c^vG was significantly correlated with sand, silt, and clay contents at the observed scale. Joint multifractal analyses, however, indicated that the parameter ~vG was not correlated with silt and sand contents at multiple scales. The parameter n was positively correlated with clay content at multiple scales. Sand content was significantly correlated with the parameter n at the observed scale but not at multiple scales. Clay contents were strongly correlated to both water-retention parameters because clay content was relatively low in the soil studied, indicating that water retention was dominated by clay content in the field of this study at all scales. These suggested that multiple-scale analyses were necessary to fully grasp the spatial variability of soil water-retention characteristics.

关键词： clay content multiple-scale analysis sand content silt content van Genuchten parameters

Effect of Nitrogen Management on Yield and water Use Efficiency of Rainfed Wheat and Maize in Northwest China

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Pedosphere 2006年第4期16卷 495-504页

作者： DANG Ting-Hui CAI Gui-Xin GUO Sheng-Li HAO Ming-De L. K. HENG institute of soil and water conservation Cliinese Academy of Sciences and Ministry of Water Resources Northwest SciTech University of Agriculture and Forestry Yangling 712100 （China）. Institute of soil Science Chinese Academy of Sciences Nanjing 210008 （China） FAO/IAEA Agriculture and Biotechnology Laboratory Seibersdorf （Austria）

A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to 2002. The local cropping sequence of wheat, wheat-beans, maize, and wheat over the 4-year period was adopted. A micro-plot study using ^15N-lahelled fertilizer was carried out to determine the fate of applied N fertilizer in the first year. When N fertilizer was applied wheat （years 1, 2 and 4） and maize （year 3） grain yield increased significantly （P 〈 0.05）（〉 30%）, with no significant yield differences in normal rainfall years （Years 1, 2 and 3） for N application at the commonly application rate and at 2/3 of this rate. Grain yield of wheat varied greatly between years, mainly due to variation in annual rainfall. Results of ^15N studies on wheat showed that plants recovered 36.6%-38.4% of the N applied, the N remained in soll （0-40 cm） ranged from 29.2% to 33.6%, and unaccounted-for N was 29.5%-34.2%. The following crop （wheat） recovered 2.1%- 2.8% of the residual N from N applied to the previous wheat crop with recovery generally decreasing in the subsequent three crops （beans, maize and wheat）.

关键词： wheat maize ^15N studies water use efficiency yield

The off-site implications of deforestation on sedimentation rates and pollution in Abkenar open water (Anzali Lagoon, Caspian Sea) using radionuclide techniques and sediment quality indices

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International Journal of Sediment Research 2022年第3期37卷 370-382页

作者： Mohammadreza Gharibreza Mohammad Zaman Mahmood Arabkhedri Shahriar Sobh-Zahedi soil conservation and watershed Management Research Institute Agricultural Research Education and Extension Organization (AREEO) soil and water Management & Crop Nutrition Section Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture International Atomic Energy AgencyVienna International Centre Guilan Agricultural and Natural Resources Research and Education Center AREEO

Abkenar open water(AOW) has a 35 km~2 distribution and is the largest part of the Anzali Lagoon in the southern coastal zone of the Caspian Sea. The effects of deforestation in the upstream basin of the AOW were assessed by measuring the rate of sedimentation, sediment contamination, and ecological risk for aquatic life and end-users using radioisotopes Cesium-137 and Lead-210. The chronology of the AOW sediment column was studied using the Constant Rate of Supply model. Correlations between environmental changes and the sedimentary regime of the study area highlight the contribution of the AOW authorized international and local wood harvesting companies pre-and-post 1950 in the catchment in terms of the rate of sediment supply and the influx of toxic metals. Historical evidence shows that two specific layers formed during World Wars I and II with the mean rates of 0.185 ± 0.04(±STD) and 0.32 ± 0.02 kg/(m·y), respectively. The highest influx of alkali elements and toxic metals(nickel, cadmium, lead, zinc, and copper) into the basin occurred in 1945. Two layers of gray mud(16-50 cm) and organic-rich dark loss mud(0-16 cm) correlated well with the programmed wood harvesting *** layers accumulated from 1953 to 2000 with a mean rate of 0.6 ± 0.2 and 2 ± 0.7 kg/(m~2·y). Thus,aquatic life and end-users have been exposed to moderate to extremely high levels of toxic metals and a moderate level of contamination since the 1950 s.

关键词： Abkenar open water Accumulation rate Anzali Lagoon Sediment contamination CRS model Radioisotopes

Effects of artificially cultivated biological soil crusts on soil nutrients and biological activities in the Loess Plateau

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Journal of Arid Land 2014年第6期6卷 742-752页

作者： YanMin ZHAO QingKe ZHU Ping LI LeiLei ZHAO LuLu WANG XueLiang ZHENG Huan MA College of water and soil conservation Beijing Forestry University Key Laboratory of Forest Ecology and Environment State Forestry Administration Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry Kunming Forest Exploration & Design Institute of State Forestry agency Anhui Survey and Design Institute for water Resources and Hydropower Planning and Design Institute of Forest Products Industry State Forestry Administration

Biological soil crusts （BSCs） play an important role in the early succession of vegetation restoration in the Loess Plateau, China. To evaluate the effects of artificially cultivated BSCs on the soil surface micro-envir- onment, we obtained natural moss crusts and moss-lichen crusts from the Loess Plateau of Shaanxi province, and subsequently inoculated and cultivated on horizontal and sloping surfaces of loess soil in a greenhouse. The chemical and biological properties of the subsoil under cultivated BSCs were determined after 10 weeks of cul- tivation. The results indicated that BSCs coverage was more than 65% after 10 weeks of cultivation. Moss crust coverage reached 40% after 5 weeks of cultivation. Compared with the control, soil organic matter and available nitrogen contents in moss crust with the horizontal treatments increased by 100.87% and 48.23%, respectively; increased by 67.56% and 52.17% with the sloping treatments, respectively; they also increased in moss-lichen crust with horizontal and sloping treatments, but there was no significant difference. Available phosphorus in cultivated BSCs was reduced, soil pH was lower and cationic exchange capacity was higher in cultivated BSCs than in the control. Alkaline phosphatase, urease and invertase activities were increased in artificially cultivated BSCs, and alkaline phosphatase activity in all cultivated BSCs was obviously higher than that in the control. Numbers of soil bacteria, fungi and actinomycetes were increased in the formation process of cultivated BSCs. These results indicate that BSCs could be formed rapidly in short-term cultivation and improve the mi- cro-environment of soil surface, which provides a scientific reference for vegetation restoration and ecological reconstruction in the Loess Plateau. China.

关键词： biological soil crusts soil nutrient enzyme activity soil microorganism Loess Plateau

Effects of straw size in buried straw layers on water movement in adjacent soil layers

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 74-84页

作者： Yao Mingze Li Bo Wang Tieliang Feng Xue College of water conservation Shenyang Agricultural UniversityShenyang 110866China

Deeply buried straw retention can improve the soil content of organic matter,its capacity for moisture preservation,the agroecological environment utilization efficiency of water resources,ensuring a stable crop yield;at the same time,the quantitative effects of deeply buried straw retention on soil moisture have a direct influence on the promotion and application of the *** an infiltration and evaporation experiment of a one-dimensional soil column,the effects of straw size on the water content of the straw and the adjacent soil were evaluated when the straw was deeply buried in soil;the infiltration and evaporation features of different sized straw and its adjacent soil were analyzed;the hydraulic conductivity,sorptivity and saturated water content of the straw were obtained;in the end,the water distribution laws of straw and adjacent soil under the same conditions were *** experiment was comprised of rod-shaped straw(RS),segment-shaped straw(SS)and filament-shaped straw(FS)to control treatment(CK).The results indicated that from the perspective of infiltration,the infiltration rate of filament-shape straw was the lowest at the stage of straw *** hydraulic conductivities of rod-shaped,filament-shaped and segment-shaped straws are 4.01 mm/min,1.33 mm/min and 0.03 mm/min at the stage of straw and adjacent soil saturation,*** is a strong effect on preventing infiltration from segment-shaped straw;with the help of the Philip model of long duration,the sorptivity of the soil with rod-shaped,filament-shaped and segment-shaped straws was 12.31 mm/min0.5,11.02 mm/min0.5 and 24.26 mm/min0.5 at the unsaturation stage,*** segment-shape straw improved the water absorption capacity of the soil and straw *** water retention capacities indicated that the saturated water contents of sandy loam,filament-shaped straw,segment-shaped straw and rod-shaped straw were 0.38 cm^(3)/cm^(3),0.29 cm^(3)/cm^(3),0.26 cm^(3)

关键词： deeply buried straw straw size soil moisture infiltration evaporation water retention

soil Environmental Index For Slovak Agricultural Land

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Pedosphere 2014年第1期24卷 137-144页

作者： J.VILCEK R.BUJNOVSKY Department of Geography and Regional Development Faculty of Humanities and Natural SciencesUniversity of Presov soil Science and conservation Research Institute

The soil environmental index(SEI),which is a four digit code system,represents relatively homogenous spatial unit with specific soil capacity to provide ecological or non-production *** work aimed to present information on rating and economic evaluation of SEI,which is a spatial identifier used for expressing heterogeneity of Slovak agricultural soil to support analysis of soil ecological *** this study,SEI index expressed the capacity of soil to accumulate water,immobilise the risk elements and substances and transform risk substances(organic pollutants).Partial evaluations of soil capacity to provide above mentioned functions were used to derive final SEI *** the agricultural soils of Slovakia there were 493 combinations of soil environmental *** index was expressed through rating(point)value and economic *** value of Slovak agricultural land to provide selected ecological soil functions was 55.3 points,which corresponded to 35.946 billionper agricultural land or approximately 1.42per square *** identification of SEI codes and relevant database were developed in vector form via geographical information systems of soil Science and conservation Research Institute,*** addition to using the national soil database system,a strategy was presented for evaluating and pricing of soil ecological function,and the development of an soil environmental *** and evaluation of vitally important soil functions expressed by SEI can significantly contribute to planning and protection of the soil,and can regulate indiscriminate anthropic interventions in land use decisions.

关键词： ecological soil functions environmental potential soil evaluation

Assessment of gully erosion susceptibility using different DEM-derived topographic factors in the black soil region of Northeast China

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International soil and water conservation Research 2023年第1期11卷 97-111页

作者： Donghao Huang Lin Su Lili Zhou Yulu Tian Haoming Fan College of water Conservancy Shenyang Agricultural UniversityShenyang110866China College of Forestry Shenyang Agricultural UniversityShenyang110866China Key Laboratory of soil Erosion Control and Ecological Restoration in Liaoning ProvinceShenyang110866China College of Urban and Environmental Sciences Northwest UniversityXi'an710127China

As a primary sediment source,gully erosion leads to severe land degradation and poses a threat to food and ecological ***,identification of susceptible areas is critical to the prevention and control of gully *** study aimed to identify areas prone to gully erosion using four machine learning methods with derived topographic *** topographic attributes(elevation,slope aspect,slope degree,catchment area,plan curvature,profile curvature,stream power index,and topo-graphic wetness index)were derived as feature variables controlling gully occurrence from digital elevation models with four different pixel sizes(5.0 m,12.5 m,20.0 m,and 30.0 m).A gully inventory map of a small agricultural catchment in Heilongjiang,China,was prepared through a combination of field surveys and satellite *** topographic attribute dataset was randomly divided into two portions of 70%and 30%for calibrating and validating four machine learning methods,namely random forest(RF),support vector machines(SVM),artificial neural network(ANN),and generalized linear models(GLM).Accuracy(ACC),area under the receiver operating characteristic curve(AUC),root mean square error(RMSE),and mean absolute error(MAE)were calculated to assess the performance of the four machine learning methods in predicting spatial distribution of gully erosion susceptibility(GES).The results suggested that the selected topographic attributes were capable of predicting GES in the study catchment area.A pixel size of 20.0 m was optimal for all four machine learning *** RF method described the spatial relationship between the feature variables and gully occurrence with the greatest accuracy,as it returned the highest values of ACC(0.917)and AUC(0.905)at a 20.0 m *** RF was also the least sensitive to resolutions,followed by SVM(ACC=0.781-0.891,AUC=0.724-0.861)and ANN(ACC=0.744-0.808,AUC=0.649-0.847).GLM performed poorly in this study(ACC=0.693-0.757,AUC=0.608-0.703).Ba

关键词： Gully erosion Machine learningmethods Topographicattribute Pixel size Northeast China

Prediction of the Maturity of Greenhouse Grapes Based on Imaging Technology

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Plant Phenomics 2022年第1期4卷 357-370页

作者： Xinguang Wei Linlin Wu Dong Ge Mingze Yao Yikui Bai College of water Conservancy Shenyang Agricultural UniversityShenyang 110866China Institute of soil and water conservation Northwest A&F University712100YanglingShaanxi ProvinceChina

To predict grape maturity in solar greenhouses,a plant phenotype-monitoring platform(Phenofix,France)was used to obtain RGB images of grapes from expansion to *** and longitudinal diameters,compactness,soluble solid content(SSC),titratable acid content,and the SSC/acid of grapes were measured and *** color values(R,G,B,H,S,andI)of the grape skin were determined and subjected to a back-propagation neural network algorithm(BPNN)to predict grape maturity.

关键词： maturity greenhouse content

Assessment of deforestation impact on soil erosion in loess formation using 137Cs method (case study: Golestan Province, Iran)

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International soil and water conservation Research 2020年第4期8卷 393-405页

作者： Mohammadreza Gharibreza Mohammad Zaman Paolo Porto Emil Fulajtar Lotfollah Parsaei Hossein Eisaei Department of River and Coastal Engineering Soil Conservation and Watershed Management Research InstituteAgricultural ResearchEducation and Extension Organization(AREEO)Tehran***TehranIran Department of soil and water Management&Crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureViennaA-1400Austria Department of Agriculture Mediterranean UniversityLocalitàFeo di VitoReggio Calabria86124Italy Department of watershed Management Golestan Agricultural and Natural Resources Research and Education CenterAREEOGorgan491567755Iran

Golestan,a province in the North-East of Iran,is characterized by high coverage of loess *** 1963,the area has experienced approximately 200,000 ha deforestation due to land-use changes in agriculture and increasing demand for ***,110,000 ha of the clear-cut lands are under dry-farming,mainly for wheat cropping,and about 86,000 ha have been *** IAEA funded project is the first attempt to use nuclear techniques in the East of Hircanian Forest for determination of on-site impacts of deforestation due to two land-use changes(*** farming and reforestation).Practicing long-term dry-farming led to 60%soil losses with a mean rate of 2 mm per *** net erosion rate of croplands on loess deposits in the study area was 32.27 t ha-1 ***,cultivation of even-aged Cypress trees since 1993,showed 13 to 60 percent effectiveness in soil ***-farming land use resulted in the loss of 95 t ha-1 soil organic carbon(SOC)stock at a mean rate of 1.7 t ha-1 over 54 *** Cypress trees successfully restored the SOC content by 100%compared with the SOC in original *** conversion of dry-farming lands to orchards of olive trees since 2004,brought more income for farmers but were less effective in soil conservation because of low canopy cover of olive *** data provide key information and guidance for land users and decisionmakers about implementing strategic and sustainable conservation practices to restore degraded land.

关键词： Hircanian forests Golestan province Nuclear technique soil erosion Deforestation Afforestation Dry-farming land