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Changes in sediment discharge in a sediment-rich region of the Yellow River from 1955 to 2010: implications for further soil erosion control

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Journal of Arid Land 2014年第5期6卷 540-549页

作者： JuYing JIAO ZhiJie WANG GuangJu ZHAO WanZhong WANG XingMin MU institute of soil and water conservation Northwest A&F University institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water Resources

The well-documented decrease in the discharge of sediment into the Yellow River has attracted considerable attention in recent years. The present study analyzed the spatial and temporal variation of sediment yield based on data from 46 hydrological stations in the sediment-rich region of the Yellow River from 1955 to 2010. The results showed that since 1970 sediment yield in the region has clearly decreased at different rates in the 45 sub-areas controlled by hydrological stations. The decrease in sediment yield was closely related to the intensity and extent of soil erosion control measures and rainstorms that occurred in different periods and sub-areas. The average sediment delivery modulus（SDM） in the study area decreased from 7,767.4 t/（km^2·a） in 1951–1969 to 980.5 t/（km^2·a） in 2000–2010. Our study suggested that 65.5% of the study area with the SDM below 1,000 t/（km^2·a） is still necessary to control soil deterioration caused by erosion, and soil erosion control measures should be further strengthened in the areas with the SDM above 1,000 t/（km^2·a）.

关键词： sediment delivery modulus(SDM) Yellow River hydrological station(s)-controlled sub-area soil and water conservation

soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

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Journal of Integrative Agriculture 2013年第10期12卷 1872-1883页

作者： XIAO Lie LIU Guo-bin XUE Sha ZHANG Chao State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water Resource

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess *** soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,*** results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly *** Shannon richness and Shannon evenness of PLFAs significantly increased after 10 yr of ***-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment *** analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community *** soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural ***,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.

关键词： abandoned cropland microbial diversity phospholipid fatty acid(PLFA) redundancy analysis(RDA) Loess Plateau

Interactions between wind and water erosion change sediment yield and particle distribution under simulated conditions

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Journal of Arid Land 2015年第5期7卷 590-598页

作者： TUO Dengfeng XU Mingxiang ZHAO Yunge GAO Liqian State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water Resources

Wind and water erosion are among the most important causes of soil loss, and understanding their interactions is important for estimating soil quality and environmental impacts in regions where both types of erosion occur. We used a wind tunnel and simulated rainfall to study sediment yield, particle-size distribution and the fractal dimension of the sediment particles under wind and water erosion. The experiment was conducted with wind ero- sion firstly and water erosion thereafter, under three wind speeds （0, 11 and 14 m/s） and three rainfall intensities （60, 80 and 100 ram/h）. The results showed that the sediment yield was positively correlated with wind speed and rain- fall intensity （P〈0.01）. Wind erosion exacerbated water erosion and increased sediment yield by 7.25%-38.97% relative to the absence of wind erosion. Wind erosion changed the sediment particle distribution by influencing the micro-topography of the sloping land surface. The clay, silt and sand contents of eroded sediment were also posi- tively correlated with wind speed and rainfall intensity （P〈0.01）. Wind erosion increased clay and silt contents by 0.35%-19.60% and 5.80%-21.10%, respectively, and decreased sand content by 2.40%-8.33%, relative to the absence of wind erosion. The effect of wind erosion on sediment particles became weaker with increasing rainfall intensities, which was consistent with the variation in sediment yield. However, particle-size distribution was not closely correlated with sediment yield （P〉0.05）. The fractal dimension of the sediment particles was significantly different under different intensities of water erosion （P〈0.05）, but no significant difference was found under wind and water erosion. The findings reported in this study implicated that both water and wind erosion should be controlled to reduce their intensifying effects, and the controlling of wind erosion could significantly reduce water erosion in this wind-water erosion crisscross region.

关键词： sediment yield particle-size distribution fractal dimension wind and water erosion

Fractal features of soil profiles under different land use patterns on the Loess Plateau, China

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Journal of Arid Land 2014年第5期6卷 550-560页

作者： Lie XIAO Sha XUE GuoBin LIU Chao ZHANG State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F University institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water Resources

Fractal theory is becoming an increasingly useful tool to describe soil structure dynamics for a better understanding of the performance of soil systems. Changes in land use patterns significantly affect soil physical, chemical and biological properties. However, limited information is available on the fractal characteristics of deep soil layers under different land use patterns. In this study, the fractal dimensions of particle size distribution（PSD） and micro-aggregates in the 0–500 cm soil profile and soil anti-erodibility in the 0–10 cm soil profile for 10 typical land use patterns were investigated in the Zhifanggou watershed on the Loess Plateau, China. The 10 typical land use patterns were： slope cropland, two terraced croplands, check-dam cropland, woodland, two shrublands, orchard, artificial and natural grasslands. The results showed that the fractal dimensions of PSD and micro-aggregates were all significantly influenced by soil depths, land use patterns and their interaction. The plantations of shrubland, woodland and natural grassland increased the amount of larger micro-aggregates, and decreased the fractal dimensions of micro-aggregates in the 0–40 cm soil profile. And they also improved the aggregate state and aggregate degree and decreased dispersion rate in the 0–10 cm soil profile. The results indicated that fractal theory can be used to characterize soil structure under different land use patterns and fractal dimensions of micro-aggregates were more effective in this regard. The natural grassland may be the best choice for improving soil structure in the study area.

关键词： fractal dimension anti-erodibility soil profile land use pattern Loess Plateau

Influence of vegetation parameters on runoff and sediment characteristics in patterned Artemisia capillaris plots

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Journal of Arid Land 2014年第3期6卷 352-360页

作者： GuanHua ZHANG GuoBin LIU PingCang ZHANG Liang YI Department of soil and water conservation Changjiang River Scientific Research Institute State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources institute of soil and water conservation Northwest A&F University Hubei Academy of Environmental Sciences

Vegetation patterns are important in the regulation of earth surface hydrological processes in arid and semi-arid areas. Laboratory-simulated rainfall experiments were used at the State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau, Yangling, northwestern China, to quantify the effects of Artemisia capillaris patterns on runoff and soil loss. The quantitative relationships between runoff/sediment yield and vegetation parameters were also thoroughly analyzed using the path analysis method for identifying the reduction mechanism of vegetation on soil erosion. A simulated rainfall intensity of 90 mm/h was applied on a control plot without vegetation （Co） and on the other three different vegetation distribution patterns： a checkerboard pattern （CP）, a banded pattern perpendicular to the slope direction （BP）, and a single long strip parallel to the slope direction （LP）. Each patterned plot received two sets of experiments, i.e. intact plants and roots only, respectively. All treatments had three replicates. The results showed that all the three other different patterns （CP, BP and LP） of A. capillaris could effectively reduce the runoff and sediment yield. Compared with Co, the other three intact plant plots had a 12%-25% less runoff and 58%-92% less sediment. Roots contributed more to sediment reduction （46%-70%）, whereas shoots contributed more to runoff reduction （57%-81%）. BP and CP exhibited preferable controlling effects on soil erosion compared with LP. Path analysis indicated that root length density and plant number were key parameters influencing runoff rate, while root surface area density and root weight density were central indicators affecting sediment rate. The results indicated that an appropriate increase of sowing density has practical significance in conserving soil and water.

关键词： arid and semi-arid areas Artemisia capillaris patches runoff and sediment roots and shoots vegetation parameters

Diurnal and seasonal variations of soil respiration rate under different row-spacing in a Panicum virgatum L. field on semi-arid Loess Plateau of China

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Journal of Arid Land 2016年第3期8卷 341-349页

作者： HUANG Jin GAO Zhijuan CHEN Ji ZHANG He XU Bingcheng institute of soil and water conservation Northwest A&F University State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources

soil respiration（SR） in crop field is affected by environmental factors, agronomic practices and crop types. To clarify how planting density affects the SR dynamics in switchgrass（Panicum virgatum L.） field on the semi-arid Loess Plateau, this research investigated diurnal and seasonal changes of soil respiration rate（RS） under three different row-spacing treatments（20, 40 and 60 cm） in the fourth growing year of switchgrass. Results showed that RS presented a pronounced seasonality under all row-spacing treatments. The highest daily average RS values appeared in August, while the lowest（P〉 0.05） among the row-spacing treatments, and similar results were found for soil temperature in 0–15 cm soil depth. soil respiration temperature sensitivity（Q_（10）） values were 1.0–3.7 during the growing months, which were strongly correlated with air temperature in May and June and the soil temperature at 15 cm depth in August. Higher aboveground biomass production and lower RS in most growth months indicated that 20 cm row-spacing treatment was beneficial for increasing the carbon fixation in switchgrass field. Results also implied that it is necessary to take into account the influence of phenology and root growth of switchgrass on soil respiration for accurately evaluating the carbon cycle in the region.

关键词： switchgrass row-spacing soil temperature soil water Q_(10) value

Effects of land-use types on the vertical distribution of fractions of oxidizable organic carbon on the Loess Plateau, China

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Journal of Arid Land 2016年第2期8卷 221-231页

作者： SUN Caili XUE Sha CHAI Zongzheng ZHANG Chao LIU Guobin institute of soil and water conservation Northwest A&F University institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water Resources College of Forestry Northwest A&F University

The oxidizability of soil organic carbon （SOC） influences soil quality and carbon sequestration. Four fractions of oxidizable organic carbon （very labile （C1）, labile （C2）, less labile （C3） and non-labile （C4）） reflect the status and composition of SOC and have implications for the change and retention of SOC. Studies of the fractions of oxidizable organic carbon （OC） have been limited to shallow soil depths and agroecosystems. How these fractions respond at deep soil depths and in other types of land-use is not clear. In this study, we evaluated the vertical distributions of the fractions of oxidizable organic carbon to a soil depth of 5.0 m in 10 land-use types in the Zhifanggou watershed on the Loess Plateau, China. Along the soil profile, C1 contents were highly variable in the natural grassland and shrubland I （Caragana microphylla）, C2 and C4 contents were highly variable in the natural grassland and two terraced croplands, respectively, and C3 contents varied little. Among the land-use types, natural grassland had the highest C1 and C2 contents in the 0-0.4 m layers, followed by shrubland I in the 0-0.1 m layer. Natural grassland had the highest C4 contents in the 1.0-4.5 m layers. Natural grassland and shrubland I thus contributed to improve the oxidizability of SOC in shallow soil, and the deep soil of natural grassland has a large potential to sequester SOC on the Loess Plateau.

关键词： Iand-use types deep soil oxidizable organic-carbon fractions Loess Plateau

Coupling between the Grain for Green Program and a household level-based agricultural eco-economic system in Ansai,Shaanxi Province of China

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Journal of Arid Land 2020年第2期12卷 199-214页

作者： LI Yue WANG Jijun HAN Xiaojia GUO Mancai CHENG Simin QIAO Mei ZHAO Xiaocui institute of soil and water conservation Northwest A&F UniversityYangling 712100China institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China

The implementation of the Grain for Green Program(GGP)has changed the development track of the agricultural eco-economic system in *** response to the results of a lag study that investigated the coupling between the GGP and the agricultural eco-economic system in a loess hilly region,we used a structural equation model to analyze the survey data from 494 households in Ansai,a district of Yan’an City in Shaanxi Province of China in *** model clarified the direction and intensity of the coupling between the GGP and the agricultural eco-economic *** coupling benefits were derived through linkages between the program and various chains in the agricultural eco-economic *** GGP,the agroecosystem of Ansai and their potential coupling effects were in a state of general *** agroecosystem directly affected the coupling effect,with the standardized path coefficient of 0.87,indicating that the agroecosystem in Ansai at this stage provided basic material support for the coupling between the GGP and the agricultural eco-economic *** direct path coefficient of agroeconomic system impacted on the coupling effect was-0.76,indicating that partial contradictions occurred between the agroeconomic system and the coupling ***,although the current agroecosystem in Ansai should be provided sufficient agroecological resources for the benign coupling between the program and the agricultural eco-economic system,agricultural development failed to effectively transform agroecological resources into agricultural economic advantages in this region,which resulted in a relative lag in the development of the agricultural economic ***,the coupling between the GGP and the agricultural eco-economic system was *** improve the coupling and the sustainable development of the agricultural eco-economic system in cropland retirement areas,the industrial structure needs to be diversified,the agricultural resources(including agroecological r

关键词： Grain for Green Program agroecosystem agroeconomic system agrosocial system coupling effect household structural equation model

Relationship Between soil and water conservation Practices and soil Conditions in Low Mountain and Hilly Region of Northeast China

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Chinese Geographical Science 2014年第2期24卷 147-162页

作者： ZHANG Yubin CAO Ning XU Xiaohong ZHANG Feng YAN Fei ZHANG Xinsheng TANG Xinlong State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources College of Plant Science Jilin University soil and water conservation institute of Jilin Province Monitoring Center of soil and water conservation Songliao Water Resources CommissionMinistry of Water Resources

The soil and water conservation practices of ecological restoration(ER),fish scale pit(FP),furrow and ridge tillage across the slope(FR),shrub strips(SS),and vegetation-covered ridge(VR)are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province,Northeast *** study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of *** samples were collected from five soil and water conservation sites(ER,FP,FR,SS,and VR)and two controls(BL and CT)to investigate their *** evaluate the influence of soil and water conservation practices on soil quality,an integrated quantitative index,soil quality index(QI),was developed to compare the soil quality under the different soil and water conservation *** results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties,especially soil organic carbon(SOC),can be recovered under soil and water conservation practice in ***,the QI in the five soil and water conservation practices and two controls was in the following order:ER>VR>BL>FR>CT>SS>*** exhibited a higher soil quality value on a slope *** the low mountain and hilly region of Northeast China,ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.

关键词： soil and water conservation practices soil property soil organic carbon low mountain and hilly region Northeast China