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International Soil and Water Conservation research 2013年第2期1卷 19-25页

作者： S.S.Kukal S.S.Bawa School of Climate Change and agricultural Meteorology Punjab Agricultural UniversityLudhianaIndia Zonal research station for Kandi Area(PAL) NawanshaharIndia

The soil conservation strategies adopted in the catchments of Shiwaliks,the most fragile region in the Himalayan ecosystem,failed to serve their purpose after a few years of their execution.A study was carried out in four differentially-treated catchments to monitor the variation in runoff and soil *** treatments imposed during 1988 included fencing,planting native vegetation and engineering structures in catchment I;planting native vegetation and fencing in catchment II;fencing alone in catchment III in addition to an untreated catchment *** soil loss during the initial years(1989–1995)of imposition of the treatments was lowest(25.2 t ha^(-1))in catchment I,treated to the maximum extent and highest(43.3 t ha^(-1))in untreated catchment *** the later period(1996–2006)the trends reversed,i.e.,catchment IV recorded the lowest(14.1 t ha^(-1))soil loss whereas catchment I recorded the highest(23.4 t ha^(-1))soil loss despite the fact that there was no change in the status of soil conservation or the characteristics of the *** runoff was 71%higher in untreated catchment than in treated catchments initially and this difference decreased to 27%during the later period.

关键词： Catchment Gully erosion Sediment loss Soil conservation

Current status and future trends of precision agricultural aviation technologies

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International Journal of agricultural and Biological Engineering 2017年第3期10卷 1-17页

作者： Yubin Lan Chen Shengde Bradley K Fritz College of Engineering South China Agricultural University/National Center for International Collaboration Research on Precision Agricultural Aviation Pesticides Spraying Technology(NPAAC)Guangzhou 510642China Department of Biological and agricultural Engineering Texas A&M UniversityCollege StationTX 77845USA Texas A&M AgriLife research and Extension Center BeaumontTX 77713USA United States Department of Agriculture(USDA) Agricultural Research Service(ARS)Aerial Application Technology Research UnitCollege StationTexas77845USA

Modern technologies and information tools can be used to maximize agricultural aviation productivity allowing for precision application of agrochemical *** paper reviews and summarizes the state-of-the-art in precision agricultural aviation technology highlighting remote sensing,aerial spraying and ground verification ***,the authors forecast the future of precision agricultural aviation technology with key development directions in precision agricultural aviation technologies,such as real-time image processing,variable-rate spraying,multi-sensor data fusion and RTK differential positioning,and other supporting technologies for UAV-based aerial *** review is expected to provide references for peers by summarizing the history and achievements,and encourage further development of precision agricultural aviation technologies.

关键词： precision agricultural aviation technology remote sensing aerial spraying UAV pesticide ground verification

Influence of peach(Prunus persica Batsch)phenological stage on the short-term changes in oxidizable and labile pools of soil organic carbon and activities of carbon-cycle enzymes in the North-Western Himalayas

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Pedosphere 2020年第5期30卷 638-650页

作者： Sovan DEBNATH Brij Lai ATTRI Anil KUMAR Arun KISHOR Raj NARAYAN Kanchan SINHA Arpan BHOWMIK Anil SHARMA Desh Beer SINGH Indian Council of agricultural research(lCAR)-Central Institute of Temperate Horticulture Regional StationMukteshwarNainitalUttarakhand 263138(India) Department of agricultural Chemistry and Soil Science Faculty of AgricultureBidhan Chandra Krishi ViswavidyalayaMohanpurWest Bengal 741252(India) Indian Council of agricultural research(ICAR)-Directorate of Mushroom research SolanHimachal Pradesh 173213(India) A Indian Council of agricultural research(ICAR)-Indian agricultural Statistics research Institute New Delhi 110012(India) Department of agricultural Statistics Faculty of AgricultureBidhan Chandra Krishi ViswavidyalayaMohanpurWest Bengal 741252(India) Indian Council of agricultural research(ICAR)-Central Institute of Temperate Horticulture SrinagarJammu and Kashmir 190007(India)

The labile organic carbon(C)and C-related enzymes are sensitive indicators capturing alterations of soil organic matter(SOM),even in a short-time *** the effects of crop husbandry and land use change on these attributes have been well studied,there is no consensus about how plant phenology may impact *** study aimed to determine the short-term effect o f six distinct phenological stages(PS-1:full bloom;PS-2:fruit set;PS-3:pit hardening;PS-4:physiological maturity;PS-5:60 d after physiological maturity;and PS-6:fall)o f peach on the changes in soil organic carbon(SOC)fractions of different oxidizability,labile C pools,and C-cycle enzyme activities in soils,for two consecutive years(2015 and 2016)in the North-Western Himalayas(NWH).Peach rhizosphere soils were sampled at the topsoil(0-15 cm)and subsoil(16-30 cm)layers,along with rhizosphere soils from adjacent perennial grasses,which served as a *** for most of the assessed parameters,including very labile C,labile C,microbial biomass C,permanganate oxidizable C,dissolved organic C,mineralizable C,amylase activity,and carboxymethyl-cellulase activity,were significantly(P<0.05)higher at PS-3 than at other phenological stages of ***,a sudden decline in these soil variables was recorded at PS-5,followed by a slight buildup at PS-6,particularly in the topsoil of the peach ***-term changes in organic C fractions of different oxidizability,influenced by peach phenological stage,significantly(P<0.05)affected C management index,C pool index,and lability *** the C management index and lability index showed their highest values at PS-3 and their lowest values at PS-5,clearly indicating short-term accretion and depletion of SOC,in tandem with the peach phenological *** component analysis suggested that a composite of soil indicators,including microbial biomass C,dissolved organic C,amylase,and invertase,could help detect short-term changes in SOC *** i

关键词： carbon fractions fruit orchard Indian Himalaya plant phenology rhizosphere soil soil biological indicators

Bio-amelioration of alkali soils through agroforestry systems in central Indo-Gangetic plains of India

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Journal of Forestry research 2014年第4期25卷 887-896页

作者： Y.P.Singh Gurbachan Singh D.K.Sharma Central Soil Salinity research Institute Regional Research StationLucknow (U.P.) 226005 India Indian Council of agricultural research New Delhi 110001 India Central Soil Salinity research Institute Karnal Haryana 132001 India

A long-term field study was initiated during 1995 at Central Soil Salinity research Institute, Regional research station, Lucknow （26047＇58＂ N and 80°46＇24＂ E） to analyze the effect of agroforestry systems on amelioration of alkali soils. Three agroforestry systems （pas- toral, silvipastoral and silvicultural） were compared with the control where no agroforestry system was introduced. Tree-based silvicultural and silvipastoral systems were characterized by tree species Prosopis juliflora and Acacia nilotica along with grass species Leptochloafusca, Panicum maximum, Trifolium alexandrium and Chloris gayana. Growth of ten-year-old Prosopis juliflora and Acacia nilotica planted in combi- nation with grasses was significantly higher over the silviculture system with the same species. Tree biomass yields of P. juliflora （77.20 t·ha-1） and A. nilotica （63.20 t·ha-1） planted under silvipastoral system were significantly higher than the sole plantation of （64.50 t·ha-1 and 52.75 t·ha-1）. Fodder yield under the pastoral system was significantly higher than the silvipastoral system during initial years but it was at par with that of silvipastoral systems after eight years of plantation. The microbial biomass carbon in the soils of silvipastoral systems was significantly higher than in soils under sole plantation of trees and control systems. The Prosopis-based silvipastoral system proved more effective in reduc- ing soil pH, displacing Na＋ from the exchange complex, increasing or- ganic carbon and available N, P and K. Improvement in soil physical properties such as bulk density, porosity, soil moisture and infiltration rate was higher in the Prosopis-based silvipastoral system than in the silviculture system or control On the basis of biomass production and improvement in soil health due to tree ＋ grass systems, silvipastoral agroforestry system could be adopted for sustainable reclamation ofhighly alkali soils.

关键词： agroforcstry systems alkali soils biomass production mi-crobial biomass soil amelioration

Insecticidal,antimicrobial and antioxidant activities of bulb extracts of Allium sativum

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Asian Pacific Journal of Tropical Medicine 2012年第5期5卷 391-395页

作者： Balaji Meriga Ramgopal Mopuri T.MuraliKrishna Department of Biochemistry Sri Venkateswara UniversityTirupati-517501.India Department of Entomology Regional Agricultural Research StationTirupatiIndia

Objective:To evaluate the insecticidal,antimicrobial and antioxidant activities of bulb extracts of Allium sativum(***).Methods:Dried bulbs of *** were extracted with different solvents and evaluated for insecticidal,antimicrobial and antioxidant ***: Aqueous and methanol extracts showed highest insecticidal activity(mortality rate of 81%and 64%respectively) against the larvae of Spodoptera litura(***) at a concentration of 1000 *** regard to antimicrobial activity,aqueous extract exhibited antibacterial activity against gram positive(Bacillus subtilis,Staphylococcus aureu,) and gram negative(Escherichia coli and Klebsiella pneumonia) strains and antifungal activity against Candida *** methanol extract showed antimicrobial activity against all the tested micro organisms except two(Staphylococcus aureus and Candida albicans),the extracts of hexane,chloroform and ethyl acetate did not show any anti microbial *** inhibitory concentration of aqueous and methanol extracts against tested bacterial and fungal strains was 100-150μg/mL. Antioxidant activity of the bulb extracts was evaluated in terms of inhibition of free radicals by 2.2’-*** and methanol extracts exhibited strong antioxidant activity(80%-90%of the standard).Conclusions:Antioxidant and antimicrobial activity of *** against the tested organisms therefore,provides scientific basis for its utilization in traditional and folk ***,our results demonstrated the insecticidal efficacy of A. sativum against ***,a polyphagous insect.

关键词： Allium sativum Insecticidal activity Antimicrobial activity Antioxidant property

The antimicrobial interventions of cilantro(Coriandrum sativum)in mitigating cross-contamination of foodborne pathogens during the retail soaking process

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Food Quality and Safety 2022年第4期6卷 571-578页

作者： Yangjin Jung Mengqi Guo Jingwen Gao Hyein Jang Karl R.Matthews agricultural&Environmental research station West Virginia State UniversityInstituteWVUSA Department of Food Science Rutgers UniversityNew BrunswickNJUSA

The efficacy of commercially available antimicrobials for fresh produce—electrolyzed water(EW;around 60 mg/L of free chlorine),a combination of lactic acid and phosphoric acid-based(LPA)and citric acid-based(CA)—was compared with tap water(TW)in preventing cross-contamination during the soaking step of crisping at a retail setting.A bunch of cilantro((103.7±14.9)g/bunch)was inoculated with a three-strain cocktail of nalidixic acid-resistant Salmonella enterica(***)and Escherichia coli(***)O157:H7,*** and Listeria monocytogenes(***),or *** O157:H7 and ***(around 5.0 log CFU/g).One inoculated and seven non-inoculated cilantro bunches were soaked in 76 L of TW,EW,LPA,and CA for 5 *** additional soakings,each with eight bunches of non-inoculated cilantro,were performed in the same soaking *** determine the cross-contamination of inoculated foodborne pathogens via soaking water,the cilantro samples and soaking water following each soaking step were subjected to microbiological analyses using selective media supplemented with nalidixic acid(100μg/mL).During the first soaking,significantly greater reductions in Salmonella((2.9±0.5)log CFU/g),*** O157:H7((3.0±0.1)log CFU/g),and ***((2.7±0.3)log CFU/g)on cilantro were achieved with EW compared to soaking with TW,LPA,and CA(P<0.05).Cross-contamination of foodborne pathogens from inoculated cilantro to non-inoculated cilantro was completely mitigated by EW during three subsequent soaking *** the exception of TW soaking water,no inoculated foodborne pathogens were detected in the 100 mL soaking water of EW,CA,and LPA *** an appropriate concentration of chemical antimicrobial in water during the soaking step of crisping aids in mitigating cross-contamination of foodborne pathogen(s)in cilantro bunches.

关键词： Cross-contamination retail settings cilantro antimicrobials post-harvest washing Escherichia coli O157:H7 Salmonella Listeria monocytogenes

Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China

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Journal of Arid Land 2024年第5期16卷 668-684页

作者： SONG Dacheng ZHAO Wenzhi LI Guangyu WEI Lemin WANG Lide YANG Jingyi WU Hao MA Quanlin College of Forestry Gansu Agricultural UniversityLanzhou 730070China Gansu Hexi Corridor Forest Ecosystem National research station Gansu Desert Control Research InstituteLanzhou 730070China Linze Inland River Basin research station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 ***,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian *** study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain *** March 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand *** sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were *** indicated a predominance of fine and medium sands in the surface sediments of the study *** deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,*** trend became markedly pronounced a decade after the deployment of clay–sand *** effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment *** particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the *** contrast,the contents of finest particles such as silt and clay were higher in the downwind

关键词： clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area

Machine learning-based crop recognition from aerial remote sensing imagery

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Frontiers of Earth Science 2021年第1期15卷 54-69页

作者： Yanqin TIAN Chenghai YANG Wenjiang HUANG Jia TANG Xingrong LI Qing ZHANG Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China USDA-agricultural research Service Aerial Application Technology Research UnitCollege StationTX 77845USA

Timely and accurate acquisition of crop distribution and planting area information is important for making agricultural planning and management *** study employed aerial imagery as a data source and machine learning as a classification tool to statically and dynamically identify crops over an agricultural cropping *** analysis of pixel-based and object-based classifications was performed and classification results were further refined based on three types of object features(layer spectral,geometry,and texture).Static recognition using layer spectral features had the highest accuracy of 75.4%in object-based classification,and dynamic recognition had the highest accuracy of 88.0%in object-based classification based on layer spectral and geometry *** identification could not only attenuate the effects of variations on planting dates and plant growth conditions on the results,but also amplify the differences between different ***-based classification produced better results than pixel-based classification,and the three feature sets(layer spectral alone,layer spectral and geometry,and all three)resulted in only small differences in accuracy in object-based *** recognition combined with objectbased classification using layer spectral and geometry features could effectively improve crop classification accuracy with high resolution aerial *** methodologies and results from this study should provide practical guidance for crop identification and other agricultural mapping applications.

关键词： machine learning crop recognition aerial imagery dynamic recognition static recognition

Nitrogen mobility,ammonia volatilization,and estimated leaching loss from long-term manure incorporation in red soil

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Journal of Integrative Agriculture 2017年第9期16卷 2082-2092页

作者： HUANG Jing DUAN Ying-hua XU Ming-gang ZHAI Li-mei ZHANG Xu-bo WANG Bo-ren ZHANG Yang-zhu GAO Su-duan SUN Nan College of Resources and Environment Hunan Agricultural UniversityChangsha 410128P.R.China Institute of agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences(CAAS)/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China Red Soil Experimental station of CAAS in Hengyang/National Observation and research station of Farmland Ecosystem in Qiyang Qiyang 426182P.R.China Key Laboratory of Ecosystem Network Observation and Modeling/Yucheng Comprehensive Experiment station Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China USDA agricultural research Service San Joaquin Valley Agricultural Sciences CenterCA 93648-9757USA

Nitrogen（N） loss from fertilization in agricultural fields has an unavoidable negative impact on the environment and a better understanding of the major pathways can assist in developing the best management practices. The aim of this study was to evaluate the fate of N fertilizers applied to acidic red soil（Ferralic Cambisol） after 19 years of mineral（synthetic） and manure fertilizer treatments under a cropping system with wheat-maize rotations. Five field treatments were examined： control（CK）, chemical nitrogen and potash fertilizer（NK）, chemical nitrogen and phosphorus fertilizer（NP）, chemical nitrogen, phosphorus and potash fertilizer（NPK） and the NPK with manure（NPKM, 70% N from manure）. Based on the soil total N storage change in 0–100 cm depth, ammonia（NH_3） volatilization, nitrous oxide（N_2O） emission, N plant uptake, and the potential N leaching loss were estimated using a mass balance approach. In contrast to the NPKM, all mineral fertilizer treatments（NK, NP and NPK） showed increased nitrate（NO_3~–） concentration with increasing soil depth, indicating higher leaching potential. However, total NH_3 volatilization loss was much higher in the NPKM（19.7%） than other mineral fertilizer treatments（≤4.2%）. The N_2O emissions were generally low（0.2–0.9%, the highest from the NPKM）. Total gaseous loss accounted for 1.7, 3.3, 5.1, and 21.9% for NK, NP, NPK, and NPKM treatments, respectively. Estimated N leaching loss from the NPKM was only about 5% of the losses from mineral fertilizer treatments. All data demonstrated that manure incorporation improved soil productivity, increased yield, and reduced potential leaching, but with significantly higher NH_3 volatilization, which could be reduced by improving the application method. This study confirms that manure incorporationis an essential strategy in N fertilization management in upland red soil cropping system.

关键词： soil NO_3~–-N ammonia volatilization nitrogen leaching long-term field experiment mass balance nitrous oxide emission

Laboratory evaluation of the GreenSeeker^(TM) handheld optical sensor to variations in orientation and height above canopy

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International Journal of agricultural and Biological Engineering 2012年第1期5卷 43-47页

作者： Daniel E Martin Juan D Lopez Jr Yubin Lan USDA-ARS Southern Plains Agricultural Research CenterCollege StationTexas 77845USA

Handheld optical sensors recently have been introduced to the agricultural *** handheld sensors are able to provide operators with Normalized Difference Vegetative Index(NDVI)data when cloud cover prevents acquisition of satellite or aerial *** research addressed the sensitivity of the GreenSeeker handheld optical sensor to changes in orientation and height above a ryegrass *** boxes were oriented both parallel and perpendicular to the light beam from the sensor head and heights of 30.5 cm(12”),61.0 cm(24”),91.5 cm(36”),122 cm(48”)and 152 cm(60”)were *** indicated that the sensor was highly sensitive(P<0.0001)to both height above canopy and orientation of the sensor relative to the *** should follow manufacturer’s recommendations on operating height range of 81-122 cm and orient the sensor head in-line with the target to obtain maximum signal response.

关键词： remote sensing NDVI GreenSeeker handheld optical sensor spectral reflectance