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Quantitative analysis of soil pores under natural vegetation successions on the loess plateau

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 laboratory of soil erosion and dryland farming on the loess plateau,institute of soil and water conservation,northwest agriculture & forestry university,yangling 712.00,china 2 Graduate university of Chinese Academy of Sciences,Beijing 100049,china 3 institute of Subtropical agriculture,Chinese Academy of Sciences,Changsha 410125,china 1. state key laboratory of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling 712100 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 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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土壤水分对钾离子固液相分配特征的影响

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土壤学报 2004年第3期41卷 466-470页

作者：朱咏莉王益权吴金水中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室中国科学院亚热带农业生态研究所长沙410125 西北农林科技大学资源环境学院

土壤水分状况是影响钾离子在土壤固液相分配转化和作物吸收利用的重要因子~[1～3]。对于植物所必须的钾素来说，土壤水溶性钾和交换性钾是土壤钾库中最活跃的组分~[4-7]。钾在土壤固、液相间的转化速率与数量分配关系取决于土壤水分的... 详细信息

土壤水分状况是影响钾离子在土壤固液相分配转化和作物吸收利用的重要因子~[1～3]。对于植物所必须的钾素来说，土壤水溶性钾和交换性钾是土壤钾库中最活跃的组分~[4-7]。钾在土壤固、液相间的转化速率与数量分配关系取决于土壤水分的存在形态以及K~+与土壤固液相表面的作用方式，并反映了土壤固钾能力~[8-11]。在以往的研究中，通常采用田间持水量或饱和含水量情况下土壤提取液(即土壤溶液)作为平衡溶液~[9-11]。在本研究中以表征土壤水分存在状态的能量指标(基质吸力)为基础，以不同吸力下的提取液为平衡溶液，研究不同水分状况钾离子在土壤固液相间的转化和分配特征，以期为揭示阳离子型养分在土壤固相表面的作用机理及评价土壤对钾吸附能力和供钾能力提供一定的理论依据。

关键词：土壤水分钾离子土壤固液相分配土壤固液相转化

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冻融作用对黑土坡面融雪、风力和降雨侵蚀的影响研究

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水土保持学报 2024年第4期38卷 63-71页

作者：赵娅君郑粉莉毋冰龙潘勋成郑润禾赵录友王雪松莫帅豪西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 中国科学院水利部水土保持研究所陕西杨凌712100

[目的]研究冻融作用对东北黑土区坡面土壤侵蚀的影响,可加深对黑土坡面侵蚀过程机理的认识,并为区域侵蚀治理提供重要科学依据。[方法]以东北黑土区单一侵蚀营力驱动的融雪、风力和降雨侵蚀为对照,通过设计冻融-融雪、冻融-风力、冻融-... 详细信息

[目的]研究冻融作用对东北黑土区坡面土壤侵蚀的影响,可加深对黑土坡面侵蚀过程机理的认识,并为区域侵蚀治理提供重要科学依据。[方法]以东北黑土区单一侵蚀营力驱动的融雪、风力和降雨侵蚀为对照,通过设计冻融-融雪、冻融-风力、冻融-降雨双侵蚀营力叠加的模拟试验,分析冻融作用对坡面融雪、风力和降雨侵蚀的影响。试验处理包括1次冻融作用、2个融雪径流量(1,2 L/min)、1个风速(12 m/s),1个降雨强度(100 mm/h)和1个坡度(3°)。[结果](1)冻融作用显著增加坡面融雪、风力和降雨侵蚀量(p1次冻融作用使坡面融雪侵蚀在1,2 L/min融雪径流下分别增加2042.9%和777.9%,使风蚀量和降雨侵蚀量分别增加118.0%和74.9%。(2)冻融作用对坡面水蚀(融雪和降雨侵蚀)过程的影响大于对径流过程的影响,且加剧坡面侵蚀过程,使坡面侵蚀活跃期历时增长和侵蚀强度增加;冻融作用也使风力侵蚀的输沙高度增加30%,各高度风蚀输沙量均增加50%以上。(3)冻融作用降低土壤抗侵蚀能力,其使表层土壤密度、土壤抗剪强度、土壤硬度分别显著减小2.5%,22.6%,15.0%。同时,冻融作用使水蚀过程中的坡面水流流速平均增加13.6%~25.0%,水流剪切力平均增加2.3%~81.9%,而阻力系数减小1.6%~20.6%,进而加剧坡面侵蚀过程。[结论]冻融作用改变侵蚀动力与阻力关系,加剧坡面融雪、风力和降雨侵蚀过程。

关键词：冻融作用融雪侵蚀风力侵蚀降雨侵蚀东北黑土区

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Spatial-temporal Analysis and Prediction of Precipitation Extremes: A Case Study in the Weihe River Basin, china

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Chinese Geographical Science 2022年第2期32卷 358-372页

作者： QIU Dexun wu Changxue MU Xingmin zhao Guangju GAO Peng 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 ResourcesYangling 712100China university of Chinese Academy of Sciences Beijing 100049China state key laboratory of soil erosion and dryland farming on the loess plateau Institute of Soil and Water ConservationNorthwest Agriculture and Forestry UniversityYangling 712100China

Extreme precipitation events bring considerable risks to the natural ecosystem and human *** the spatial-temporal characteristics of extreme precipitation and predicting it quantitatively are critical for the flood prevention and water resources planning and *** this study,daily precipitation data(1957–2019)were collected from 24 meteorological stations in the Weihe River Basin(WRB),northwest china and its surrounding *** first analyzed the spatial-temporal change of precipitation extremes in the WRB based on space-time cube(STC),and then predicted precipitation extremes using long short-term memory(LSTM)network,auto-regressive integrated moving average(ARIMA),and hybrid ensemble empirical mode decomposition(EEMD)-LSTM-ARIMA *** precipitation extremes increased as the spatial variation from northwest to southeast of the *** were two clusters for each extreme precipitation index,which were distributed in the northwestern and southeastern or northern and southern of the *** precipitation extremes in the WRB present a strong clustering ***,the pattern of only high-high cluster and only low-low cluster were primarily located in lower reaches and upper reaches of the WRB,*** spots(25.00%–50.00%)were more than cold spots(4.17%–25.00%)in the *** spots were mainly concentrated in the northwestern part,while hot spots were mostly located in the eastern and southern *** different extreme precipitation indices,the performances of the different models were *** accuracy ranking was EEMD-LSTM-ARIMA>LSTM>ARIMA in predicting simple daily intensity index(SDII)and consecutive wet days(CWD),while the accuracy ranking was LSTM>EEMD-LSTM-ARIMA>ARIMA in predicting very wet days(R95 P).The hybrid EEMD-LSTM-ARIMA model proposed was generally superior to single models in the prediction of precipitation extremes.

关键词： precipitation extremes space-time cube(STC) ensemble empirical mode decomposition(EEMD) long short-term memory(LSTM) auto-regressive integrated moving average(ARIMA) Weihe River Basin,china

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退耕还林前后渭河流域土壤保持功能变化

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中国水土保持科学 2024年第4期22卷 102-108页

作者：吴常雪翁学先徐瑞瑞高鹏穆兴民赵广举西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 江西省上饶市玉山县水利局江西上饶334700 中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100

基于InVEST模型的土壤保持模块,定量评估退耕还林前后渭河流域土壤保持功能的变化,并统计不同土地利用类型及坡度下的土壤保持量。结果表明:1)相较于1980年,2020年实际土壤侵蚀量减少1.40亿t,平均土壤侵蚀模数减少1033.51 t/(km^(2)·a)... 详细信息

基于InVEST模型的土壤保持模块,定量评估退耕还林前后渭河流域土壤保持功能的变化,并统计不同土地利用类型及坡度下的土壤保持量。结果表明:1)相较于1980年,2020年实际土壤侵蚀量减少1.40亿t,平均土壤侵蚀模数减少1033.51 t/(km^(2)·a),微度侵蚀的比例由60.75%增加至77.43%,土壤保持总量由48.60亿t增加到53.73亿t;2)不同土地利用类型中,草地的土壤保持量最大,占土壤保持总量的40%以上;而单位面积土壤保持量最大的是林地;3)0~5°的微坡地区土壤保持量最小,单位面积的土壤保持量也最低;>15°~25°的较陡坡地区土壤保持量最大,占土壤保持总量的1/3以上。退耕还林工程主要通过减少土壤侵蚀量来提高土壤保持功能,随着植被恢复,不同土地利用类型及坡度的土壤保持功能增强。研究结果可为流域植被恢复效果和土壤保持功能的定量评估提供参考。

关键词： InVEST模型土壤保持退耕还林渭河流域

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Effects of nitrogen addition on plant-soil-microbe stoichio-metry characteristics of different functional group species in Bothriochloa ischemum community

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soil Ecology Letters 2022年第4期4卷 362-375页

作者： ZiWen zhao YanLi Qin Yang wu WenJing Chen Sha Xue GuoBin Liu state key laboratory of soil erosion and dryland farming on the loess plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China key laboratory of National forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an University of TechnologyXi'an 710048China

Nitrogen(N)deposition,the source of N input into terrestrial ecosystems,is exhibiting an increasingly serious impact on the biogeochemical cycle and functional stability of *** are an important component of terrestrial ecosystems and play a key role in maintaining terrestrial ecosystem ***,it is critical to understand the effects of nitrogen addition on grassland *** conducted gradientN addition experiments(0,3,6,and 9 g N m^(-2)2 y^(-1))for threeyears ingrassland communities with similar site *** utilized four typical herbaceous plants,including the dominant species Bothriochloa ischemum(***)and companion species Stipa bungeana(***),Artemisia gmelinii(***),and Cleistogenes squarrosa(***),to explore how different plant-soil-microbe systems respond to N *** homeostasis analysis demonstrated that both plants and microbes were strictly ***,the companion species were found to be more susceptible to P dominant ***,aggravated overlap in stoichiometric niches between plant species were observed at the N6 and N9 *** analysis indicated that the vector angle was>45°regardlessof plant species and N levels,suggesting that there was a strong Plimitation in the rhizosphere microbial *** partitioning analysis revealed that the Composite roots exhibited a greater effect(explaining 34.7% of the variation)on the rhizosphere microbes than on the Gramineae,indicating that there may be more intense nutrient competition in its ***,the effects of N addition on species were different a cross functional groups,with a significant positive effect on the Gramineae(***,***,and ***)and a significant negative effecton the Compositae(***),which should be fully considered in the future ecological management and restoration.

关键词： N addition Ecological stoichiometry Stoichiometric homeostasis Nutrient limitation Stoichiometric niche Plant-soil-microbe system

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A Fractal Method of Estimating soil Structure Changes Under Different Vegetations on Ziwuling Mountains of the loess plateau,china

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Agricultural Sciences in china 2006年第7期5卷 530-538页

作者： zhao Shi-wei SU Jing YANG Yong-hui LIU Na-na wu Jin-shui SHANGGUAN Zhou-ping institute of soil and water conservation Northwest A ＆ F University Yangling 712100 P.R.China state key laboratory of soil erosion and dryland agriculture Institute of Soil and Water Conservation the Chinese Academy of Sciences Yangling 712100 P.R.China College of Resources and Environment Northwest A ＆ F University Yangling 712100 P.R.China institute of Subtropical agriculture the Chinese Academy of Sciences Changsha 410125 P.R.China

Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension was used to study the soil structure in soil at different stages of vegetative succession on the Ziwuling Mountains. The land use and vegetation types included cultivated land, abandoned land, grassland, two types of shrub land, and three types of forests. The grassland, shrub land, and forested areas represented a continuum in vegetative succession that had occurred naturally, as the land was abandoned in 1862. Disturbed and undisturbed soil samples were collected from ten vegetation types from depths of 0-10, 10-20, and 20-30 cm on the Ziwuling Mountains, at a site with an elevation of about 1 500 m. Particle size distribution was determined by the pipette method and aggregate size distribution was determined by wet sieving. The results were used to calculate the particle and aggregate fractal dimension. The results showed that particle and aggregate fractal dimensions varied between vegetation types. There was a positive correlation between the particle fractal dimension and the weight of particles with diameter 〈 0.001 mm, but no relationship between particle fractal dimension and the other particle size classes. Particle fractal dimension was lower in vegetated soils compared to cropland and there was no consistent relationship between fractal dimension and vegetation type. Aggregate fractal dimension was positively correlated with the weight of 〉 0.25 mm aggregates. Aggregate fractal dimension was lower in vegetated soils compared with cropland. In contrast to particle fractal dimension, aggregate fractal dimension described changes in soil structure associated with vegetative succession. The results of this study indicate that aggregate fractal dimension is more effective in describing soil structure and function compared with particle fractal d

关键词： soil fractal dimension soil particle soil aggregate vegetation type Ziwuling Mountains

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Impact of Coal Mining Subsidence on Sandy Geomorphology and Vegetation Habitat in Sandy Area

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Asian Agricultural Research 2021年第5期13卷 19-23,30页

作者： Guoping zhao Puxia wu Weibo SHEN key laboratory of state forestry Administration on soil and water conservation & Ecological Restoration of loess plateau Shaanxi Academy of Forestry Xi'an 710082 China College of Natural Resources and Environment Northwest A&F University Yangling 712100 China state key laboratory of soil erosion and dryland farming on the loess plateau Institute of Soil and Water Conservation CAS & MWR Yangling 712100 China

[Objectives]To explore the problem of"secondary desertification"caused by coal mining subsidence in sandy area and its control countermeasures.[Methods]The collapse fissure changes,vegetation displacement and tilt,dry sand layer and wind erosion/aeolian deposit rate of the edge,middle and basin of subsidence area were studied in detail.[Results]The width and density of fissures at the edge of subsidence area were the smallest,followed by those in the center,and the width and density of fissures in the basin of the subsidence area were the greatest,while the staggering and surface damage showed the opposite *** average displacement length of vegetation in the subsidence area reached 60 cm,the slope was 5.67-28.63,and the maximum wind erosion/aeolian deposit at the trunk roots was-30.52 cm/+25.41 cm,most serious at the edge of *** changes in displacement length and slope of vegetation were positively linearly correlated with the height and surface damage of collapse *** thickness of dry land layer at the edge of the subsidence area reached 14 cm,4-6 cm greater than that of the control,and the thickness of dry land layer in the middle and basin of the subsidence area was both about 11 cm,1-4 cm greater than that of non-subsidence *** wind erosion rate at the edge of the subsidence area was up to 83.34%,followed by that(52.06%)in the *** aeolian deposit rate in the subsidence basin was 51.84%.[Conclusions]The subsidence edge has the strongest impact on the sandy geomorphology and vegetation habitat,and is a key area for ecological *** is recommended that the coal mining subsidence should be treated in a timely manner to avoid the occurrence of"secondary desertification".

关键词： Sandy area Coal mining subsidence Sandy geomorphology Vegetation habitat

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Assessing the collapse risk of Stipa bungeana grassland in china based on its distribution changes

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Journal of Arid Land 2020年第2期12卷 303-317页

作者： QIAO Xianguo GUO Ke LI Guoqing zhao Liqing LI Frank Yonghong GAO Chenguang state key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China university of Chinese Academy of Sciences Beijing 100049China state key laboratory of soil erosion and dryland farming on the loess plateau Northwest A&F UniversityYangling 712100China institute of soil and water conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China Ministry of Education key laboratory of Ecology and Resource Use of the Mongolian plateau&Inner Mongolia key laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China

The criteria used by International Union for conservation of Nature(IUCN) for its Red List of Ecosystems(RLE) are the global standards for ecosystem-level risk assessment, and they have been increasingly used for biodiversity conservation. The changed distribution area of an ecosystem is one of the key criteria in such assessments. The Stipa bungeana grassland is one of the most widely distributed grasslands in the warm-temperate semi-arid regions of china. However, the total distribution area of this grassland was noted to have shrunk and become fragmented because of its conversion to cropland and grazing-induced degradation. Following the IUCN-RLE standards, here we analyzed changes in the geographical distribution of this degraded grassland, to evaluate its degradation and risk of collapse. Past(1950-1980) distribution areas were extracted from the Vegetation Map of china(1:1,000,000). Present realizable distribution areas were equated to these past areas minus any habitat area losses. We then predicted the grassland’s present and future(under the Representative Concentration Pathway 8.5 scenario) potential distribution areas using maximum entropy algorithm(MaxEnt), based on field survey data and nine environmental layers. Our results showed that the S. bungeana grassland was mainly distributed in the loess plateau, Hexi Corridor, and low altitudes of the Qilian Mountains and Longshou Mountain. This ecosystem occurred mainly on loess soils, kastanozems, steppe aeolian soils and sierozems. Thermal and edaphic factors were the most important factors limiting the distribution of S. bungeana grassland across china. Since 56.1% of its past distribution area(4.9×10~4 km^2) disappeared in the last 50 a, the present realizable distribution area only amounts to 2.2×10~4 km^2. But only 15.7% of its present potential distribution area(14.0×10~4 km^2) is actually occupied by the S. bungeana grassland. The future potential distribution of S. bungeana grassland was predicted t

关键词： climate change limiting factors maximum entropy algorithm potential distribution realizable distribution Red List of Ecosystems loess plateau

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基于极值概率分布函数的中国早稻高温热害时空分布统计特征

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中国生态农业学报 2018年第11期26卷 1601-1612页

作者：何亮吴门新侯英雨赵刚靳宁于强国家气象中心北京100081 拜耳公司数字农业部朗根费尔德40764 西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室杨凌712100 澳大利亚悉尼科技大学生命科学学院

揭示水稻高温热害风险特征对农业适应气候变化具有重要意义。本研究以中国早稻种植区为研究区域,基于早稻种植区214个气象站1971—2015年的数据,利用Mann-Kendall非参数趋势检验方法和极值概率分布理论,探究中国早稻高温热害的时空变化... 详细信息

揭示水稻高温热害风险特征对农业适应气候变化具有重要意义。本研究以中国早稻种植区为研究区域,基于早稻种植区214个气象站1971—2015年的数据,利用Mann-Kendall非参数趋势检验方法和极值概率分布理论,探究中国早稻高温热害的时空变化趋势和极值概率分布规律。研究发现:1)反映早稻高温热害的两个指标即高温热害累计天数(ADHS,accumulateddaysofheatstress)和热害有害积温(HDD,heatstressdegree days)的均值在湖南中南部、江西中部、浙江和福建中部较大,表明这些区域的早稻遭受高温热害的风险较大;从Mann-Kenall趋势检验看,两个指标在超过1/3的站点都呈显著增加的趋势,说明高温热害风险在这些站点显著增加,尤其20世纪90年代以后超过1/2的站点两个指标都呈显著增加的趋势。2)超过1/2以上的站点的高温热害累计天数和高温有害积温都满足极值概率函数分布。对于高温热害累计天数,56个站点满足耿贝尔分布(Gumbel),82个站点满足广义极值分布(GEV);对于热害有害积温,61个站点满足耿贝尔分布,58个站点满足广义极值分布。3)两个高温热害指标的10年、50年、100年重现期的空间分布规律和2个指标的均值空间分布类似,即均值较大的区域,其10年、50年、100年重现期对应的重现期水平(return level)也较大;重现期水平与经度、纬度和海拔无明显相关关系。研究结果有助提升对早稻高温热害时空趋势和概率分布规律的认识,可为农业适应气候变化和农业天气指数保险设计等方面提供理论参考。

关键词：早稻高温热害累计天数热害有害积温时空分布极值概率分布

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