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Effects of physical crust on soil detachment by overland flow in the Loess Plateau region of China

International soil and water Conservation Research 2024年第1期12卷 107-120页

作者： Jiaxin Liu Liding Chen Bing Wang Xiaoyu Peng School of Ecology and Environmental science Yunnan UniversityKunming650091China State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYanglingShaanxi712100China University of Chinese Academy of sciences Beijing100049China

Physical soil crust(PSC),a key component of surface soil structure,exists extensively in loess *** is considered to have a significant effect on soil detachment ***,the long-term effects and the corresponding mechanisms of PSC on soil detachment by overland flow are still not well understood,especially in natural *** investigate temporal variation in soil erosion resistance and the underlying factors during PSC formation,an 8×8-m soil plot was exposed to natural conditions in the Loess Plateau over a 524-day period spanning two rainy seasons and a winter between them.A flume test was conducted to determine soil detachment capacity(Dc)under six designed flow shear stress levels(5.66-22.11 Pa)using crusted(SC)and non-crusted(NSC)soil samples at different PSC development ***,two soil erosion resistance parameters,rill erodibility(K_(r))and critical shear stress(τ_(c)),were *** time,in the SC and NSC treatments,K_(r)decreased from 0.516 to 0.120 s m^(-1)and 0.521 to 0.223 s m^(-1),respectively,whileτ_(c)increased from 0.49 to 4.42 Pa and 0.26-2.46 Pa,*** in soil erosion resistance was rapid in the first one to two months,and then slowed down,with slight fluctuations *** the SC treatment,K_(r)was 42%lower andτ_(c)was 67%greater than those in the NSC *** properties changed greatly for both *** increased from 0 to 7.09 mm in the SC *** increased from 2.91 to 9.04 kPa and 3.01-4.78 kPa in SC and NSC treatments,*** soil erosion resistance parameters could be well predicted by SCT and Coh in the SC treatment(R^(2)≥0.82),while their best predictor was Coh in the NSC treatment(R^(2)≥0.90).The results demonstrate that PSC formation enhances soil erosion resistance in the soil detachment process in the loess region under natural *** study revealed the important role and complexity of PSC in the process of soil erosion,and provided theor

关键词： Physical soil crust formation soil heterogeneity Rill erodibility Critical shear stress

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Mass transfer characteristics of chiral pharmaceuticals on membrane used for polar organic chemical integrative sampler

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Journal of Environmental sciences 2024年第2期136卷 670-681页

作者： Liyang Wang Ruixia Liu Youya Zhou Peng Yuan Xiaoling Liu Hongjie Gao College of water science Beijing Normal UniversityBeijing 100018China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Technical Centre for soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China

Passive sampling technology has good application prospects for monitoring trace pollutants in aquatic *** research on the sampling mechanism of this technology is essential to improve the measurement accuracy and extend the application scope of this *** this study,adsorption and permeation experiments were performed to investigate the sorption and mass transfer properties of five chiral pharmaceuticals at the enantiomeric level on polyethersulfone(PES)and polytetrafluoroethylene(PTFE)membranes used in a polar organic chemical integrative *** adsorption experiments showed that the PES membrane had an adsorption phenomenon for most selected pollutants and an insignificant sorption behavior was observed for all selected pharmaceuticals on the PTFE membrane except for R(S)-*** diffusion coefficients of selected pharmaceuticals onto the PTFE membrane were approximately one order of magnitude higher than those onto the PES *** permeation experiment indicated that under different hydraulic conditions,the change of the relative pollutant concentration through the PTFE membrane for the composite pollutant system was more obvious than that for the single pollutant system,and mass transfer hysteresis exists for both contaminant systems through PES *** the first-order equation or 3-component model to estimate the overall mass transfer coefficients,the results showed that the overall mass transfer coefficient values of pollutants in the composite pollutant system onto both membranes were higher than those in the single pollutant *** parameter was mainly influenced by the synergistic effects of the multi-analyte interaction and diminished water boundary layers during the mass transfer process.

关键词： Sorption phenomenon Permeation behavior Mass transfer properties Modeling calculation Chiral pharmaceuticals PES and PTFE membrane

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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat

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Journal of Integrative Agriculture 2024年第5期23卷 1523-1540页

作者： Zhikai Cheng Xiaobo Gu Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang Key Laboratory of Agricultural soil and water Engineering in Arid and Semiarid AreasMinistry of Education/Northwest A&F University Yangling712100China

In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter *** on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral *** machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried *** results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth *** accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of *** purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral *** results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.

关键词： mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle

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Resistance and resilience of soil biological indicators:A case study with multi-walled carbon nanotube

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Pedosphere 2024年第3期34卷 664-675页

作者： Shagufta YASMEEN Nintu MANDAL Anupam DAS Pritam GANGULY Sanjay KUMAR Rajiv RAKSHIT department of soil science and Agricultural Chemistry Bihar Agricultural UniversitySabourBhagalpur 813210(India) department of Agronomy Bihar Agricultural UniversitySabourBhagalpur 813210(India)

soil ecosystem is experiencing stresses due to climate change,and soil inhabitants try to demonstrate their inherent resistance and resilience against those *** of nanomaterials as agricultural inputs could bring shifts in resistance and resilience patterns of soil microbes and associated enzymes,especially under short-term heat *** this background,the impacts of multi-walled carbon nanotube(MWCNT)on the resistance and resilience of soil biological indicators were *** incubation experiment was conducted with varied MWCNT concentrations(0,50,100,250,and 500 mg kg-1soil)for 90 d after 24-h heat stress at 48±2?C to assess the impacts of MWCNT on soil enzyme activities and microbial populations vis-à-vis their resistance and resilience indices under short-term exposure to heat *** activities were reduced after exposure to heat *** indices of enzyme activities were enhanced by MWCNT application on day 1 after heat stress,whereas there was no recovery of enzyme activities after 90-d *** soil enzyme activities,resistance index values of soil microbial populations followed the similar trend and were improved by MWCNT ***-walled carbon nanotube has the potential to improve resistance indices of soil enzyme activities and microbial populations under heat stress,although they could not recover to their original state during periodical incubation after heat *** study helps to understand the relative changes of biological indicators under MWCNT and their ability to withstand heat stress.

关键词： enzyme activity heat stress microbial population nanomaterial recovery

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Pursuing the goal of carbon neutrality in China:path for realization of carbon sequestration in planted forests

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Frontiers of Agricultural science and Engineering 2024年第3期11卷 355-366页

作者： Lei DENG Haitao HU Jiwei LI Xue LI Chunbo HUANG Zhijing YU Hailong ZHANG Qing QU Xiaozhen WANG Lingbo DONG Zhouping SHANGGUAN State Key Laboratory of soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University College of soil and water Conservation science and Engineering (Institute of soil and water Conservation) Northwest A&F University Shaanxi Forestry Survey and Planning Institute College of Landscape Architecture Northeast Forestry University Institute of soil and water Conservation Chinese Academy of Sciences and Ministry of Water Resources Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of Geosciences

Tree plantations are an important forest resource that substantively contributes to climate change mitigation and carbon sequestration. As the area and standing volume of tree plantations in China have increased, issues such as unreasonable structure, low productivity, limited ecological functionality and diminishing ecological stability have occurred, which hinder the ability of tree plantations to enhance carbon sequestration. This study outlined the trajectory of carbon sequestration and its associated benefits in tree plantations by examining the current state of tree plantation establishment and growth, elucidated the strategies for advantages of carbon sequestration and climate change mitigation in planted forests, and summarized the existing problems with tree plantations. This paper underscores the pressing need for concerted efforts to boost carbon sequestration within planted forests and proposes management and development strategies for Chinese tree plantations. In the future, it will be necessary to apply scientific theories to practice and develop multi-objective management optimization models for the high-quality development of tree plantations. This will involve establishing a cohesive national carbon trading market, improving the prediction of carbon sequestration, and identifying priority zones for afforestation and reforestation, to better serve China's national strategy for achieving peak carbon and carbon neutrality.

关键词： Planted forest carbon stock carbon sequestration carbon management climate change promotion path

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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM

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Journal of Mountain science 2024年第6期21卷 2025-2042页

作者： WANG Yanxia YANG Lisha HUANG Xiaoyuan ZHOU Ruliang School of soil and water Conservation Southwest Forestry UniversityKunming 650224China School of Economics and Management Southwest Forestry UniversityKunming 650224China

Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate *** and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental *** paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended ***,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM *** fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell ***,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 ***,the NSHTI strips were parameterized through raster vectorization and spatial *** Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward ***,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting ***,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 *** result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources.

关键词： High temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection

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Global black soil distribution

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Frontiers of Agricultural science and Engineering 2024年第2期11卷 271-281页

作者： Yuxin TONG Marcos E.ANGELINI Yusuf YIGINI Isabel LUOTTO Global soil Partnership Land and Water DivisionFood and Agriculture Organization of the United NationsRome 00153Italy

Black soils, characterized by their thick, dark horizons enriched with organic matter, epitomize highly fertile soils. However, their fertility precipitates intense land use, engendering challenges such as soil erosion, nutrient depletion, pollution, compaction, salinization, and acidification. Notably, these soils are significant contributors to global greenhouse gas emissions, primarily due to substantial losses in soil organic carbon. Despite these challenges, black soils are pivotal for global food production. This paper delineates the implementation of digital soil mapping for the global cartography of black soils and human interference on these soils. Predominantly distributed in Eastern Europe, Central and Eastern Asia, and North and South America, black soils cover an approximate area of 725 Mha, with the Russian Federation,Kazakhstan, and China collectively have over half of this area. Agriculturally,these soils underpin significant proportions of global crop yields, producing 66% of sunflower, 30% of wheat, and 26% of potato outputs. The organic carbon content in the upper 30 cm of these soils is estimated at 56 *** management of black soils is imperative for ensuring food security and addressing climate change on a global scale.

关键词： Black soils distribution map food security soil organic carbon

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SOLVING SYSTEMS OF PHASELESS EQUATIONS VIA RIEMANNIAN OPTIMIZATION WITH OPTIMAL SAMPLING COMPLEXITY

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Journal of Computational Mathematics 2024年第3期42卷 755-783页

作者： Jianfeng Cai Ke Wei department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina School of Data science Fudan UniversityShanghaiChina

A Riemannian gradient descent algorithm and a truncated variant are presented to solve systems of phaseless equations|Ax|^(2)=*** algorithms are developed by exploiting the inherent low rank structure of the problem based on the embedded manifold of rank-1 positive semidefinite *** recovery guarantee has been established for the truncated variant,showing that the algorithm is able to achieve successful recovery when the number of equations is proportional to the number of *** key ingredients in the analysis are the restricted well conditioned property and the restricted weak correlation property of the associated truncated linear *** evaluations show that our algorithms are competitive with other state-of-the-art first order nonconvex approaches with provable guarantees.

关键词： Phaseless equations Riemannian gradient descent Manifold of rank-1 and positive semidefinite matrices Optimal sampling complexity

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Applicability and improvement of different potential evapotranspiration models in different climate zones of China

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Ecological Processes 2024年第1期13卷 262-282页

作者： Zedong Li Yiran Li Xinxiao Yu Guodong Jia Peng Chen Pengfei Zheng Yusong Wang Bingbing Ding Key Laboratory of soil & water Conservation and Desertification Combating of Ministry of Education Beijing Forestry University College of Horticulture and Forestry sciences Tarim University State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Background Accurate estimation of potential evapotranspiration(PET) is the key for studying land-air interaction hydrological processes. Several models are used to estimate the PET based on standardized meteorological data. Although combination-based models have the highest level performance estimation of PET, they require more meteorological data and may therefore be difficult to apply in areas lacking meteorological observation *** The results showed significant differences in the spatial trends of PET calculated by different models in China, the Doorenbots–Pruitts model revealed the highest PET(1902.6 mm), and the Kuzmin model revealed the lowest PET(349.6 mm), with the largest difference being 5.5 times. The Romanenko and the Rohwer models were the recommended temperature-based and aerodynamic-based models. On the other hand, the Abtew model was more suitable for arid and semi-arid regions, while the Priestley–Taylor model was more suitable for humid regions. Combination-based models revealed ideal calculation accuracies, among which the Penman–Monteith model was the best option for PET *** The accuracy range of Romanenko, Rohwer, Abten, Priestley Taylor, and Penman Monteith models improved in MPZ and TCZ is higher than that improved in TMZ and SMZ. This does not mean that the improved models have higher accuracy in MPZ and TCZ than in TMZ and SMZ. On the contrary, the original model performed poorly in MPZ and TCZ, so the improved accuracy was relatively large. The unimproved model was already more suitable in TMZ and SMZ, so the improved accuracy was relatively small. Therefore, regional calibration of the PET models can improve the accuracy and applicability of PET calculation, providing a reference for studying hydrological processes in different climatic zones.

关键词： Potential evapotranspiration Climatic zone Temperature-based model Aerodynamic-based model Radiation-based model Combination-based model Model calibration

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A combination of straw incorporation and polymer-coated urea offsets soil ammonia and nitrous oxide emissions in winter wheat fields

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Journal of Integrative Agriculture 2024年第5期23卷 1718-1736页

作者： Xiaoyun Wang Yajie Tian Qianhui Zhang Zhengxin Zhao Rui Wang Huanjie Cai Key Laboratory of Agricultural soil and water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F UniversityYangling712100China College of water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

The combined effects of straw incorporation(SI)and polymer-coated urea(PCU)application on soil ammonia(NH_(3))and nitrous oxide(N_(2)O)emissions from agricultural fields have not been comprehensively evaluated in Northwest *** conducted a two-year field experiment to assess the effects of combining SI with either uncoated urea(U)or PCU on soil NH_(3)emissions,N_(2)O emissions,winter wheat yields,yield-scaled NH_(3)(/NH_(3)),and yield-scaled N_(2)O(/N_(2)O).Five treatments were investigated,no nitrogen(N)fertilizer(N_(0)),U application at 150 kg N ha-1 with and without SI(SI+U and S_(0)+U),and PCU application at 150 kg N ha^(-1) with and without SI(SI+PCU and S_(0)+PCU).The results showed that the NH_(3);emissions increased by 20.98-34.35%following Sl compared to straw removal,mainly due to increases in soil ammonium(NH_(4)^(+)-N)content and water-flled pore space(WFPS).SI resulted in higher N_(2)O emissions than under the So scenario by 13.31-49.23%due to increases in soil inorganic N(SIN)contents,WFPS,and soil microbial *** contrast,the PCU application reduced the SIN contents compared to the U application,reducing the NH_(3)and N_(2)O emissions by 45.99-58.07 and 18.08-53.04%,***,no significant positive effects of the SI or PCU applications on the winter wheat yield were *** lowest /NH_(3) and /N_(2)O values were observed under the S_(0)+PCU and SI+PCU *** results suggest that single PCU applications and their combination with straw are the optimal agricultural strategies for mitigating gaseous N emissions and maintaining optimal winter wheat yields in Northwest China.

关键词： straw incorporation polymer-coated urea NH_(3)and N_(2)O emissions winter wheat yields

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