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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

Difference in Organic Carbon Contents and Distributions in Particle-size Fractions between soil and Sediment on the Southern Loess Plateau, China

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Journal of Mountain Science 2014年第3期11卷 717-726页

作者： LI Guang-lu PANG Xiao-ming College of Resources and Environment Northwest A&F University Tianshui soil and water conservation Experiment station of YRCC

The purpose of this study was to assess the effect of long-term cultivation and water erosion on the soil organic carbon （OC） in particle-size fractions. The study site is located at Nihegou watershed in the Southern Loess Plateau, China. The soil at this site is loess with loose and silty structure, and contains macropores. The results showed that the OC concentrations in sediments and in the particle-size fractions of sediments were higher than those in soils and in the particle-size fractions of soils. The OC concentration was highest in the clay particles and was lowest in the sand particles. Clay particles possessed higher OC enrichment ability than silt and sand particles. The proportions of OC in the silt fractions of soil and sediment were the highest （mean value of 53.87% and 58.48%, respectively）, and the total proportion of OC in the clay and silt fractions accounted for 96% and 98% of the total OC in the soil and sediment, respectively. The loss of OC was highest in silt particles, with an average value of 0.16 Mg ha^-1 y^-1, and was lowest in the sand （0.003 Mg ha^-1 y^-l）. This result suggests that the fine particle-size fraction in the removed sediment may be an important indicator to assess soil OC losses.

关键词： soil organic carbon Loess Plateau Enrichment ratio water erosion Particle fraction

Size-and leaf age-dependent effects on the photosynthetic and physiological responses of Artemisia ordosica to drought stress

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Journal of Arid Land 2021年第7期13卷 744-758页

作者： WANG Chunyuan YU Minghan DING Guodong GAO Guanglei ZHANG Linlin HE Yingying LIU Wei Yanchi Research station School of Soil and Water ConservationBeijing Forestry UniversityBeijing 100083China Key Laboratory of State Forestry Administration on soil and water conservation Beijing Forestry UniversityBeijing 100083China

Drought is one of the most significant natural disasters in the arid and semi-arid areas of *** or plant organs often differ in their responses to drought and other adversities at different growth *** present,little is known about the size-and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of ***,we evaluated the photosynthetic and physiological responses of Artemisia ordosica *** drought stress using a field experiment in Mu Us Sandy Land,Ningxia Hui Autonomous Region,China in *** was manipulated by installing outdoor shelters,with four rainfall treatments applied to 12 plots(5 m×5 m).There were four rainfall levels,including a control and rainfall reductions of 30%,50%and 70%,each with three *** individual crown size as the dividing basis,we measured the responses of *** photosynthetic and physiological responses to drought at different growth stages,i.e.,large-sized(>0.5 m^(2))and small-sized(≤0.5 m^(2))*** leaves of *** were divided into old leaves and young leaves for separate *** showed that:(1)under drought stress,the transfer efficiency of light energy captured by antenna pigments to the photosystem II(PSII)reaction center decreased,and the heat dissipation capacity increased *** resist the photosynthetic system damage caused by drought,*** enhanced its free radical scavenging capacity by activating its antioxidant enzyme system;and(2)growth stage and leaf age had effects on the reaction of the photosynthetic system to *** *** plants could not withstand severe drought stress(70%rainfall reduction),whereas large *** individuals could absorb deep soil water to ensure their survival in severe drought stressed *** 30%and 50%rainfall reduction conditions,young leaves had a greater ability to resist drought than old leaves,whereas the latter were more resistant

关键词： drought stress age difference plant size photosynthesis physiological response survival strategy

The shifts of precipitation phases and their impacts

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Science China Earth Sciences 2025年

作者： Xuemei LI Tao CHE Yuanlong TANG Huan'e DUAN Guigang WANG Xu ZHANG Chuanming YANG Jun WU Yue ZHANG Lanhai LI Faculty of Geomatics Lanzhou Jiaotong University National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Key Laboratory of Science and Technology in Surveying & Mapping Gansu Province Key Laboratory of Cryospheric Science and Frozen soil Engineering Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Xinjiang Key Laboratory of water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese academy of Sciences Tianshan Snow Cover and Avalanche Observation and Research station of Xinjiang

Precipitation comes in various phases, including rainfall, snowfall, sleet, and hail. Shifts of precipitation phases, as well as changes in precipitation amount, intensity, and frequency, have significant impacts on regional climate, hydrology,ecology, and the energy balance of the land-atmosphere system. Over the past century, certain progress has been achieved in aspects such as the observation, discrimination, transformation, and impact of precipitation phases. Mainly including:since the1980s, studies on the observation, formation mechanism, and prediction of precipitation phases have gradually received greater attention and reached a certain scale. The estimation of different precipitation phases using new detection theories and methods has become a research focus. Avariety of discrimination methods or schemes, such as the potential thickness threshold method of the air layer, the temperature threshold method of the characteristic layer, and the near-surface air temperature threshold method,have emerged one after another. Meanwhile, comparative studies on the discrimination accuracy and applicability assessment of multiple methods or schemes have also been carried out simultaneously. In recent years, the shift of precipitation from solid to liquid (SPSL) in the mid-to-high latitudes of the Northern Hemisphere has become more pronounced due to global warming and human activities. It leads to an increase in rain-on-snow (ROS) events and avalanche disasters, affecting the speed, intensity, and duration of spring snow-melting, accelerating sea ice and glacier melting, releasing carbon from permafrost, altering soil moisture, productivity, and phenological characteristics of ecosystems, and thereby affecting their structures, processes, qualities, and service functions. Although some progress has been made in the study of precipitation phases, there remains considerable research potential in terms of completeness of basic data, reliability of discrimination schemes,

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Effects of simulated submerged and rigid vegetation and grain roughness on hydraulic resistance to simulated overland flow

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Journal of Mountain Science 2017年第10期14卷 2042-2052页

作者： YANG Ping-ping ZHANG Hui-lan MA Chao Beijing Engineering Research Center of soil and water conservation Beijing Forestry University Beijing 100083 China Jinyun Forest Ecosystem Research station School of Soil and Water Conservation Beijing Forestry University Beijing 100083 China

Better understanding of the role of vegetation and soil on hydraulic resistance of overland flow requires quantitative partition of their interaction. In this paper, a total of 144 hydraulic flume experiments were carried out to investigate the hydraulic characteristics of overland flow. Results show that hydraulic resistance is negatively correlated with Reynolds number on non-simulated vegetated slopes, while positively on vegetated slopes. The law of composite resistance agrees with the dominant resistance, depending on simulated vegetation stem,surface roughness, and discharge. Surface roughness has greater influence on overland flow resistance than vegetation stem when unit discharge is lower than the low-limited critical discharge, while vegetation has a more obvious influence when unit discharge is higher than the upper-limited critical discharge. Combined effects of simulated vegetation and surface roughness are unequal to the sum of the individual effects through t-test, implying the limitation of using linear superposition principle in calculating overland flow resistances under combined effect of roughness elements.

关键词： Hydraulic resistance Overland flow Vegetation resistance Grain resistance Flume experiment

Nutrient Loss from Various Land-Use Areas in Shixia Small watershed of Miyun County, Beijing, China

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Chinese Journal Of Geochemistry 2003年第2期22卷 173-178页

作者：王晓燕王晓峰王振刚汪青平蔡新广 College of Resource Environment & Tourism Capital Normal University soil/water conservation station of Miyun County

In the Shixia small watershed, twenty experimental plots and two monitoring channels, the residential area and livestock areas were used to monitor the flow, runoff and erosion. Nitrogen and phosphorous concentrations associated with various land uses were analyzed at the same time. The results are presented as follows: (1) TP, TN and COD concentrations of runoff samples in the residential area and livestock areas are nearly 10 times those in other land-use areas. High nutrient loads are associated with village land use, which is due to unsuitable livestock rising. These areas should be treated as the critical areas of non-point source pollution. (2) Different land-use influences intensity the loss of nutrients, especially slope tillings in agricultural land. The amount of nutrient loss from agricultural land per unit is highest, that from forestry is intermediate and that from pastures is lowest. However, in consideration of the variability of land-use areas, agricultural land contributes the greatest to TP and forestry land to TN. (3) The concentrations of TN and TP in sediments from gangues are highest, those in forestry land are intermediate, and those in agricultural land are lowest. Nutrient loss from hilly areas is much greater than from mountainous areas.

关键词：土地利用类型氮磷营养损失北京农业用地土壤侵蚀

Effect of shrub-grass vegetation coverage and slope gradient on runoff and sediment yield under simulated rainfall

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International Journal of Sediment Research 2021年第1期36卷 29-37页

作者： Dandan Han Jingcheng Deng Chaojun Gu Xingmin Mu Peng Gao Jianjian Gao State Key Laboratory of soil Erosion and Dryland Agriculture on Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources University of Chinese Academy of Sciences State Key Laboratory of soil Erosion and Dryland Agriculture on Loess Plateau Northwest A&F University Yangtze River Basin Monitoring Center station for soil and water conservation Changjiang Water Resources Commission Suide Test station of water and soil conservation Yellow River Conservancy Committee of the Ministry of Water Resources

Evaluating the benefits of sediment and runoff reduction in different vegetation types is essential for studying the mechanisms of soil and water conservation on the Loess *** experiment was conducted in shrub-grass plots with nine levels of mixed vegetation coverage from 0% to 70%,three slopes(10°,15°,and 20°) and two rainfall intensities(1.0 and 2.5 mm/min).The results showed that the vegetation coverage and slope gradient significantly affect runoff and sediment ***-grass vegetation coverage had a significant effect on the runoff start-time,runoff flow velocity,runoff rate,and soil erosion rate on *** vegetation coverage could effectively delay the runoff starttime and decrease the runoff flow ***,the effects of the slope gradient on runoff and sediment yield are opposite to those of vegetation ***-grass vegetation coverage could effectively increase runoff and sediment yield reduction benefits,while their benefits were affected by the rainfall *** the 1.0 mm/min rainfall intensity,the reduction in the sediment production rate was greater than that under the 2.5 mm/min ***,when the shrub-grass vegetation coverage exceeded 42%,the runoff reduction benefit was more obvious at higher rainfall *** cumulative sediment yield increased with increasing cumulative runoff,and the rate of increase in the cumulative runoff was greater than that of the cumulative sediment yield with increasing of shrub-grass vegetation ***,there was a power function relationship between cumulative sediment yield and cumulative runoff yield(P <0.05).Our paper is expected to provide a good reference on the ecological environment and vegetation construction on the Loess Plateau.

关键词： Simulated rainfall Shrub-grass coverage Slope Runoff and sediment yield

Flow regime changes in three catchments with different landforms following ecological restoration in the Chinese Loess Plateau

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Journal of Arid Land 2020年第1期12卷 44-57页

作者： LUO Zhidong LIU Erjia QI Shi ZHAO Nan SUN Yun College of soil and water conservation Beijing Forestry UniversityBeijing 100083China water and soil conservation Monitoring Center of Ministry of water Resources Beijing 100053China Key Laboratory of soil and water conservation of State Forestry Administration Beijing 100083China Engineering Research Center of Forestry Ecological Engineering Ministry of EducationBeijing 100083China Shanxi Institute of soil and water conservation Taiyuan 030045China

The Chinese Loess Plateau is known as one of the most severe soil erosion regions in the *** ecological restoration projects,i.e.,the integrated soil conservation project since the 1970s and the''Grain for Green''project since 1999,have been progressively implemented to control the soil erosion in this *** restoration has greatly changed flow regime over the past five ***,the mechanism of how flow regime responds to ecological restoration among landforms remains poorly *** this study,we investigated the temporal dynamics of flow regime in three catchments,i.e.,Wuqi,Honghe and Huangling hydrological stations,respectively representing the loess hilly-gully,loess table-gully and rocky mountain(covered by secondary forest)areas in the Chinese Loess Plateau,using daily hydrological data during the 1960s–*** nonparametric Mann-Kendall test,Pettitt's test and daily flow series were used to investigate the changes of flow *** negative trends of annual streamflow were detected at the Wuqi and Honghe stations,except for the Huangling *** annual baseflow at the Wuqi station showed a significantly positive trend whereas a significantly negative trend was observed at the Honghe station,and there was no significant trend at the Huangling *** was interesting that baseflow index significantly increased during the whole period in all ***,the trends and change points of daily flow series derived by different percentages of exceedance and extreme series in different consecutive days varied among *** on the change points analysis of annual streamflow,we divided data series into three periods,i.e.,the baseline period(from 1959 and 1963 to 1979,PI),the integrated soil conservation period(1980–1999,PII)and the''Grain for Green''period(2000–2011,PIII).We found that streamflow decreased due to the reduction of high streamflow(exceeding 5%of time within a year)and median streamflow(50%)

关键词： change point extreme series hydrological data soil erosion streamflow changes

Geospatial Mapping of soil Nitrate-Nitrogen Distribution Under a Mixed-Land Use System

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Pedosphere 2009年第4期19卷 434-445页

作者： S. LAMSAL C. M. BLISS D. A. GRAETZ School of Forest Resources and conservation University of Florida USDA Forest Service Southern Research Station soil and water Science Department University of Florida

Mapping the spatial distribution of soil nitrate-nitrogen （NO3=N） is important to guide nitrogen application as well as to assess environmental risk of NO3-N leaching into the groundwater. We employed univariate and hybrid geostatistical methods to map the spatial distribution of soil NO3-N across a landscape in northeast Florida. soil samples were collected from four depth increments （0-30, 30-60, 60-120 and 120-180 cm） from 147 sampling locations identified using a stratified random and nested sampling design based on soil, land use and elevation strata. soil NO3-N distributions in the top two layers were spatially autocorrelated and mapped using lognormal kriging. Environmental correlation models for NO3-N prediction were derived using linear and non-linear regression methods, and employed to develop NO3-N trend maps. Land use and its related variables derived from satellite imagery were identified as important variables to predict NO3-N using environmental correlation models. While lognormal kriging produced smoothly varying maps, trend maps derived from environmental correlation models generated spatially heterogeneous maps. Trend maps were combined with ordinary kriging predictions of trend model residuals to develop regression kriging prediction maps, which gave the best NO3-N predictions. As land use and remotely sensed data are readily available and have much finer spatial resolution compared to field sampled soils, our findings suggested the efficacy of environmental correlation models based on land use and remotely sensed data for landscape scale mapping of soil NO3-N. The methodologies implemented are transferable for mapping of soil NO3-N in other landscapes.

关键词： environmental correlation general linear model kriging land use regression

Effects of precipitation and landuse on runoff during the past 50 years in a typical watershed in the Loess Plateau, China

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International Journal of Sediment Research 2009年第3期24卷 352-364页

作者： Huaxing BI1, Bin LIU2, Jie WU3, Lei YUN3, Zhihan CHEN2 and Zhewei CUI31 Prof. in hydrology, College of soil and water conservation, Box 67, Beijing Forestry University, 35 Qinghua East Road, Haidian District, Beijing 100083, China, 2 Researcher in hydrology, Xifeng station of soil and water conservation, Xifeng, Gansu Province, China 3 Graduate Assis., College of soil and water conservation, Beijing Forestry University, Beijing 100083, China Prof. in hydrology College of soil and water conservation Box 67 Beijing Forestry University 35 Qinghua East Road Haidian District Beijing 100083 China Researcher in hydrology Xifeng station of soil and water conservation Xifeng Gansu Province China Graduate Assis. College of soil and water conservation Beijing Forestry University Beijing 100083 China

In the past century, great progress has been made worldwide in our understanding of forest-water relationship. The successful forestation programs implemented in China-which have improved the ecological environmental conditions-have gained the attention of many researchers and highlighted the relationship between forestation and water yields. The arid and semi-arid Loess Plateau has received attention from water engineers and eco-hydrological researchers in China because of a shortage in water resources. We selected one of the oldest stations conducting soil and water conservation experiments, the Xifeng soil and water conservation station, and chose the Nanxiaohe catchment and its paired catchments (Yangjiagou catchment and Dongzhuanggou catchment) as our research areas. Trends in precipitation, air temperature, streamflow over the past 50 years, and the effect of changing land use on streamflow were analyzed. The Mann-Kendall test showed that precipitation had a negative trend (downward trend), whereas air temperature showed a positive trend (upward trend) from the past to present in the Nanxiaohe catchment. However, the trends seen in precipitation, air temperature did not contain any "jumping points." The paired catchment approach is used to detect the effects of land cover change on hydrology in the Yangjiagou and the contrast catchment, i.e., Dongzhuanggou catchment in our study. The results showed a large change in land use in the Yangjiagou catchment from 1954 to 2008. An increase in forested land (from 0% to 40.08% from 1954 to 2008) and a reduction of bare land (from 51.26% to 5.50% from 1954 to 2008) accounted for a large part of the change in land use. However, the land use changed little in the contrast catchment. The comparison of streamflow in the paired catchments showed that forestation reduced streamflow by 49.63% (or 6.5 mm) each year.

关键词： Surface water hydrology Climate variability/change Forests Land use/land cover change Loess Plateau of China