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Rainwater harvesting,its prospects and challenges in the uplands of Talugtog,Nueva Ecija,Philippines

International Soil and water Conservation Research 2013年第3期1卷 56-67页

作者： Samuel M.Contreras Teresita S.Sandoval Silvino Q.Tejada bureau of soils of soils and water management the Philippines bureau of soils and water management the Philippines

The prospects and challenges facing eight small water impounding projects(SWIPs)in Talugtog,Nueva Ecija,an upland municipality located in Central Luzon,Philippines were evaluated using rapid appraisal and documentation of projects,interview of farmers and local officials,and a review of related studies undertaken on the same project *** challenges include the deterioration of structural facilities,inactive farmers associations,watershed degradation,and climate *** also aims to evaluate improvement and innovation in the future implementation of SWIPs as rainwater harvesting *** site was selected because it has the largest number of SWIPs established as one of the coping strategies during the 1997-1998 severe El *** of its location,it has no major irrigation systems and relies only on local rainwater storage *** study involves 8 SWIPs established in two clusters(i.e.,5 and 3 SWIPs in a watershed)as rainwater conservation and management *** indicated these clusters of SWIPs offer multiple benefits in terms of supplemental irrigation,inland fish production,and water for domestic purposes and livestock *** also serve as strategic small-scale upland structures that enhance recharging of groundwater,prevent flooding,and provide value-adding activities such as recreation,soil and water conservation,and environmental *** studies also identified their benefits at the farm and community levels as conserved rainwater through storage in SWIPs is translated into more economic ***,some SWIPs are confronted with various challenges;deterioration of structural facilities,inactive farmer associations,unabated watershed degradation,and threats of climate *** are seriously affecting the overall performance of *** actions should include the strengthening of small water impounding system associations(SWISA),repair and climate-proofing of structural facilities through the(SWISA

关键词： Rainwater harvesting Small water impounding project Upland watershed SWISA

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Increasing phosphorus fertilizer value of recycled iron phosphates by prolonged flooding and organic matter addition

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Pedosphere 2024年第3期34卷 631-640页

作者： Rochelle Joie SARACANLAO Hannah VAN RYCKEL Mieke VERBEECK Maarten EVERAERT Erik SMOLDERS Division of Soil and water management Department of Earth and Environmental ScienceKU LeuvenKasteelpark Arenberg 20Heverlee B-3001(Belgium) Soil Service of Belgium.Willem De Croylaan 48 Leuven 3001(Belgium)

Iron(Fe)minerals are commonly used to remove phosphorus(P)from waste streams,producing P-loaded Fe(Ⅲ)oxides or Fe(Ⅱ)phosphate minerals(e.g.,vivianite).These minerals may be used as fertilizers to enhance P circularity if solubilized in ***,we tested the P fertilizer value of recycled Fe phosphates(FePs)in a pot trial and in an incubation experiment,hypothesizing that P release from FePs is possible under Fe(Ⅲ)-reducing ***,a pot trial was set up with rice(Oryza sativa)in all combinations of soil flooding or not,three P-deficient soils(acid,neutral,and calcareous),and six FePs(three Fe(Ⅲ)Ps and three Fe(Ⅱ)Ps)referenced to triple superphosphate(TSP)or zero *** P uptake responded to TSP application in all treatments but only marginally to *** redox potential did not decrease to-200 mV by flooding for a brief period(13 d)during the pot trial.A longer incubation experiment(60 d)was performed,including a treatment of glutamate addition to stimulate reductive conditions,and P availability was assessed with CaCl_(2)extraction of *** addition and/or longer incubation lowered soil redox potential to<-100 *** the longer term,Fe(Ⅲ)minerals released P,and adequate P was reached in the calcareous soil and in the neutral soil amended with Fe(Ⅲ)*** can be concluded that prolonged soil flooding and organic matter addition can enhance the P fertilizer efficiency of ***,application of FeP in powder form may enhance P availability.

关键词： agronomic efficiency circular economy P-loaded Fe(Ⅲ)oxides paddy soil vivianite redox

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Adaptive mutation sparrow search algorithm-Elman-AdaBoost model for predicting the deformation of subway tunnels

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Underground Space 2024年第4期17卷 320-360页

作者： Xiangzhen Zhou Wei Hu Zhongyong Zhang Junneng Ye Chuang Zhao Xuecheng Bian MOE Key Laboratory of Soft soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Hangzhou Canal Group Construction management Co.LTD Hangzhou 310015China Ningbo Rail Transit Project Construction Headquarter Ningbo 315012China Center for Hypergravity Experimental and Interdisciplinary Research Zhejiang UniversityHangzhou 310058China

A novel coupled model integrating Elman-AdaBoost with adaptive mutation sparrow search algorithm(AM-SSA),called AMSSAElman-AdaBoost,is proposed for predicting the existing metro tunnel deformation induced by adjacent deep excavations in soft *** novelty is that the modified SSA proposes adaptive adjustment strategy to create a balance between the capacity of exploitation and *** AM-SSA,firstly,the population is initialized by cat mapping chaotic sequences to improve the ergodicity and randomness of the individual sparrow,enhancing the global search *** the individuals are adjusted by Tent chaotic disturbance and Cauchy mutation to avoid the population being too concentrated or scattered,expanding the local search ***,the adaptive producer-scrounger number adjustment formula is introduced to balance the ability to seek the global and local *** addition,it leads to the improved algorithm achieving a better accuracy level and convergence speed compared with the original *** demonstrate the effectiveness and reliability of AM-SSA,23 classical benchmark functions and 25 IEEE Congress on Evolutionary Computation benchmark test functions(CEC2005),are employed as the numerical examples and investigated in comparison with some wellknown optimization *** statistical results indicate the promising performance of AM-SSA in a variety of optimization with constrained and unknown search *** utilizing the AdaBoost algorithm,multiple sets of weak AMSSA-Elman predictor functions are restructured into one strong predictor by successive iterations for the tunnel deformation prediction ***,the on-site monitoring data acquired from a deep excavation project in Ningbo,China,were selected as the training and testing ***,the predictive outcomes are compared with those of other different optimization and machine learning *** the end,the obtained results in this real-world geotechnical eng

关键词： Adjacent deep excavations Existing subway tunnels Adaptive mutation sparrow search algorithm Metaheuristic optimization Benchmark test functions Elman neural networks

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Role of phosphorus on the biogeochemical behavior of cadmium in the contaminated soil under leaching and pot experiments

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Journal of Environmental Sciences 2024年第3期137卷 488-499页

作者： Hui Jia YifanWu Mengqi Zhang Jinhui Ye Daolin Du He Wang Institute of Environment and Ecology School of Emergency ManagementJiangsu UniversityZhenjiang 212013China School of the Environment and Safety Engineering&Institute of Environment and Ecology Jiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of water Treatment Suzhou University of Science and TechnologySuzhou 215009China Xuzhou Medical University Affiliated HospitalXuzhou 221004China

Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanistic roles of P in mitigating Cd toxicity to ryegrass root,and especially in alleviating the disruption of the mitochondrial function of living *** this study,the physiological and biochemical mechanisms associated with ryegrass growth under various Cd and P treatments were investigated using leaching and pot *** concentration of Cd in soil leachates showed a significantly positive relationship with redox potential(P<0.05),but negative relationship(P<0.05)with leachate pH values and dissolved organic carbon(DOC),indicating that exogenous P addition(as H_(2)PO_(4)*)may decrease Cd leaching from contaminated *** to the control(without P addition),the cumulative Cd content was reduced by 53.3%and 64.5%in the soil leachate with exogenous P application(20 mg/L and 80 mg/L),***,application of P decreased the Cd concentrations in the symplastic fractions and increased the Cd concentrations in the apoplastic fractions in root tips,which may help to alleviate Cd stress to the ***,exogenous P was found to play a positive role in mitochondrial function and Ca^(2+)variation in root cells under Cd stress,which provides novel insights into the mechanisms of exogenous P in alleviating plant Cd injury.

关键词： Phosphorus Cadmium stress Protoplast Biogeochemical behavior Mitochondrial function

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Effects of Calcium and Magnesium on Phosphorus Availability in Ferralsols and Rice Production in Forest Zones of Côte d’Ivoire

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 33-53页

作者： Guy Fernand Yao Brahima Kone Kouadio Amani Franck Michaël Lemonou Bahan Jean Lopez Essehi Brou Kouame François Lompo Albert Yao-Kouame National Center for Agronomic Research (CNRA) Central Laboratory Soils Water and Plants (LCSEP) Sustainable Soil and Water Management Program Bouaké C&ocircte d’Ivoire Soil Water and Geomaterials Sciences Laboratory (LS2EG) Earth Sciences and Mining Resources Training and Research Unit (UFR STRM) Félix Houphou&eumlt-Boigny University Abidjan C&ocircte d’Ivoire National Center for Agronomic Research (CNRA) Man Research Station Rice Program Man C&ocircte d’Ivoire Environment and Agricultural Research Institute (INERA) Ouagadougou Burkina Faso

Phosphorus bioavailability has long been a recurring problem in tropical acid soils. A pot experiment was carried out during three (3) successive rice production cycles at Adiopodoumé to evaluate the response of the NERICA 5 rice accession to various doses of calcium, magnesium and phosphorous. The experiment was conducted using a randomized split-plot design. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg·Ca·ha-1) and magnesium sulfate (0, 25, 50 and 75 kg·Mg·ha-1) and Togo natural phosphate (0, 25, 50 and 75 kg·P·ha-1) were determined at each production cycle. The results showed that single-dose natural phosphate supplementation for three cropping cycles resulted in an average enrichment of around 2 mg·P·kg-1 after each trial following its continuous dissolution, with an increase in DSP (33.31% to 70.52%). The study revealed one strategy for managing and enhancing native P with cations and another for exogenous P: there would be a synergy of Ca/Mg on native P, whereas an antagonism would characterize the two parameters in phosphate fertilization.

关键词： Soil Acidity Native and Exogenous Phosphorus Free Iron Ca/Mg Balances Rice Growing Côte d’Ivoire

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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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Influence of cutterhead opening ratio on soil arching effect and face stability during tunnelling through non-uniform soils

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Underground Space 2024年第4期17卷 45-59页

作者： Xue-Jian Chen Pei-Pei Fang Qiu-Nan Chen Jun Hu Kai Yao Yong Liu State Key Laboratory of water Resources Engineering and management Wuhan UniversityWuhan 430072China Hubei Technology Innovation Center for Smart Hydropower Wuhan 430000China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Civil and Architectural Engineering Hainan UniversityHaikou 570228China School of Qilu Transportation Shandong UniversityJinan 250002China

Tunnelling has increasingly become an essential tool in the exploration of underground space.A typical construction problem is the face instability during tunnelling,posing a great threat to associated *** face instability often occurs with the soil arching *** study investigates the combined effect of cutterhead opening ratio and soil non-uniformity on soil arching effect and face stability,via conducting random finite-element analysis coupled with Monte–Carlo *** results underscore that the face stability is strongly associated with the evolution of stress *** obtained stability factors in the uniform soils can serve as a reference for the design of support pressure in practical tunnelling *** addition,non-uniform soils exhibit a lower stability factor than uniform soils,which implies that the latter likely yields an underestimated probability of face *** tunnel face is found to have a probability of failure more than 50%if the spatial non-uniformity of soil is *** the end,a practical framework is established to determine factor of safety(FOS)corresponding to different levels of probability of face failure considering various opening ratios in non-uniform *** required FOS is 1.70 to limit the probability of face instability no more than 0.1%.Our findings can facilitate the prediction of probability of instability in the conventionally deterministic design of face pressure.

关键词： Tunnel Face stability Soil arching effect Cutterhead opening ratio Non-uniform soil Random field

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Soil type and wetting intensity control the enhancement extent of N_(2)O efflux in soil with drought and rewetting cycles

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International Soil and water Conservation Research 2024年第1期12卷 137-144页

作者： Panpan Jiao Lei Yang Zhongwu Li Peng Zheng Xiaodong Nie School of Geographical Sciences Hunan Normal UniversityChangsha 410081China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau The Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Climate change alters the intensity and frequency of drought and rewetting(D/W)events;however,the influence patterns of D/W on soil N_(2)O efflux in the water-limited area were not fully ***,the impacts of D/W cycles varying in different extent of rewetting and frequency to N_(2)O efflux in two kinds of soil on the Loess Plateau were *** incubation conditions consisted of 1)D/W treatments with four 7-day cycles from 10%water holding capacity(WHC)to 60%WHC or 90%WHC,2)constant moisture of 60%WHC and 90%*** pulse of N_(2)O efflux rate under 10-60%WHC treatment was higher than that under 10-90%WHC treatment in calcic cambisols,while opposite trend was observed in earth-cumuli-orthic ***,the pulse of N_(2)O efflux rate decreased as cycle number increased for different wetting intensities and soil *** direct N_(2)O efflux under 10-60%WHC and 10-90%WHC treatments were 5.49 and 1.89μg N_(2)O-N g^(-1)soil in calcic cambisols,with those being 1.92 and 10.85μg N_(2)O-N g^(-1)soil in earth-cumuli-orthic anthrosols,*** N loss in earth-cumuli-orthic anthrosols was approximately 5.74 times greater than that in calcic cambisols under 10-90%WHC treatment,whereas the N loss under 10-60%WHC treatment was about 2.86 times greater in calcic cambisols than that in earth-cumuli-orthic *** study suggested that extreme rainfall events can enhance the N_(2)O efflux and N loss in agricultural soils on the Loess Plateau in terms of soil type and wetting intensity,which should not be ignored in the N fertilizer management.

关键词： Drought/rewetting cycles N_(2)O efflux Wetting intensity Microbial biomass N Dissolved organic N Loess plateau

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Effect of Tillage Practices on Hydro-Physical Properties of soils in a Rice-Grown Environment in North Central Nigeria

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Journal of Environmental Protection 2024年第5期15卷 527-536页

作者： Ebierni Akpoebidimiyen Otuaro John Jiya Musa Felix Oguche Abayomi Ibrahim Kuti Abubakar Ndaman Civil Engineering Department Maritime University Okerenkoko Nigeria Department of Agricultural and Bioresources Engineering Federal University of Technology Minna Nigeria Institute of water and Environmental management Faculty of Agricultural and Food Sciences and Environmental Management University of Debrecen Boszormenyi St Hungary

This study details soil’s physical and chemical properties in a rice-grown environment in Minna environs Niger State, Nigeria, under different soil and water conservation practices. Soil samples were collected at 0 - 10 cm, 10 - 20 cm and 20 - 30 cm, respectively, using a soil auger to determine their physical and chemical properties such as moisture content, particle size, bulk density, particle density, porosity and organic matter. The textural classification determined the percentage dominance of the soil types in each study site location. The moisture content of site 1 ranged between 14.3% to 13.7%, site 2 ranged between 13.2% to 10.2%, site 3 ranged between 15.4% to 13.2%, site 4 ranged between 15.6% to 13.6% and site 5 ranged between 16.1% to 10.9%. The clay content of sites 3, 4 and 5 is higher than that of sites 1 and 2, while the silt contents of sites 1, 2 and 3 are higher than that of sites 4 and 5. The mean value of soil organic carbon from each study location was 2.37%, 2.03%, 2.43%, 2.07% and 2.17% for sites 1, 2, 3, 4, and 5, respectively. Therefore, site 1 is susceptible to erosion because of poor infiltration rate and well-ploughed or cultivated land by the tractor (harrowed). The particle sizes analysis indicated that the soil type in Site 1 and Site 2 is mainly sandy loam, while Site 3 and Site 5 are mainly loamy and predominantly clay loam in Site 4.

关键词： Degradation Erosion Fertility Irrigation management

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Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray,Ethiopia

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Journal of Arid Land 2024年第1期16卷 1-13页

作者： Selam LJALEM Emiru BIRHANE Kassa TEKA Daniel H BERHE Department of Land Resources management and Environmental Protection College of Dryland Agriculture and Natural ResourcesMekelle UniversityMekelle 231Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life Sciences(NMBU)Ås 1432Norway Department of Natural Resources management Adigrat UniversityAdigrat 50Ethiopia

Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic *** African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,*** farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,*** trees also could improve soil ***,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological ***,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental *** divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different *** collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil *** density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were *** revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under ***,and soil p H under ***,all the studied soils were improved under both species canopy as compared with canopy ***,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under *** two parkland agroforestry species significantly enhanced soil fertility near the canopy of top

关键词： agroforestry bulk density carbon stock dispersed tree soil texture tree canopy

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