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Improved and sustainable agroecosystem, food security andenvironmental resilience through zero tillage with emphasis on soilsof temperate and subtropical climate regions: A review

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International Soil and Water Conservation Research 2022年第3期10卷 530-545页

作者： Waseem Hassan Yu'e Li Tahseen Saba Fanta Jabbi Bin Wang Andong Cai jianshuang wu Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences100081BeijingChina Key Laboratory of Agricultural Environment Ministry of Agriculture and Rural AffairsBeijing 100081China Key Laboratory of National Forestry Administration on Forest Resources Conservation and Ecological Safety in the Upper Reaches of the Yangtze River College of ForestrySichuan Agricultural UniversityChengdu611130China

Tillage is one of the agricultural management practices that significantly impacts agroecosystems,crop production,and the *** tillage(CT)practices alter the soil environment and induce organic constituents’decomposition and the emission of greenhouse gases(GHGs),which contribute to the greenhouse effect and global *** organic matter,biological diversity,aggregate stability,high erosion and degradation of the soil environment,and sequestration strength are additional factors associated with CT,which negatively affect food security and environmental *** a result,CT is no more beneficial in the long run;consequently,zero tillage(ZT)could be a viable candidate for sustainable *** review to establish this systematically compared and summarized the effect of tillage systems(*** and ZT)by synthesizing and interpreting published data(>150 peer-reviewed articles)with>200 observations on soil ecosystem services and properties/agroecosystem,crop yield/food security,GHG emission,and carbon sequestration/environmental *** review established that ZT improves soil structure,aggregate stability,biological diversity,organic matter and nutrients,water and water use efficiency,and reduces soil degradation,erosion,tillage machinery impacts,and GHG *** allows timely seeding and better crop growth,increases yield and food security,improves carbon sequestration,strengthens soil storage potential,and helps to mitigate the adverse effects of climate change on environmental *** on various latent direct and indirect benefits,resource-saving ability,and broad adoption scope of ZT,it is corroborated that ZT is a practical and potential approach for improved and sustainable agroecosystem,food security,and environmental resilience.

关键词： soil tillage agroecosystem

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Alpine Grassland Aboveground Biomass and Theoretical Livestock Carrying Capacity on the Tibetan Plateau

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Journal of Resources and Ecology 2022年第1期13卷 129-141页

作者： ZHANG Xianzhou LI Meng wu jianshuang HE Yongtao NIU Ben Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences andNatural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China School of Geographic Sciences Nantong UniversityNantongJiangsu 226007China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China

The accurate simulation and prediction of grassland aboveground biomass (AGB) and theoretical livestock carrying capacity are key steps for maintaining ecosystem balance and sustainable grassland *** AGB in fenced grassland is not affected by grazing and its variability is only driven by climate change,which can be regarded as the grassland potential AGB (AGB_(p)).In this study,we compiled the data for 345 AGB field observations in fenced grasslands and their corresponding climate data,soil data,and topographical data on the Qinghai-Tibetan Plateau (TP).We further simulated and predicted grassland AGB_(p)and theoretical livestock carrying capacity under the climate conditions of the past (2000-2018) and future two decades (2021-2040) based on a random forest (RF) *** results showed that simulated AGB_(p)matched well with observed values in the field (R^(2)=0.76,P<0.001) in the past two *** average grassland AGB_(p)on the Tibetan Plateau was 102.4g m^(-2),and the inter-annual changes in AGB_(p)during this period showed a non-significant increasing ***_(p)fluctuation was positively correlated with growing season precipitation (R^(2)=0.57,P<0.001),and negatively correlated with the growing season diurnal temperature range (R^(2)=0.51,P<0.001).The average theoretical livestock carrying capacity was 0.94 standardized sheep units (SSU) ha^(-1)on the TP,in which about 54.1%of the areas showed an increasing trend during the past two *** with the past two decades,the theoretical livestock carrying capacity showed a decreasing trend in the future,which was mainly distributed in the central and northern *** study suggested that targeted planning and management should be carried out to alleviate the forage-livestock contradiction in grazing systems on the Tibetan Plateau.

关键词： alpine grassland aboveground biomass carrying capacity climate change random forest Tibetan Plateau

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Effects of Grazing Exclusion on Plant Productivity and Soil Carbon, Nitrogen Storage in Alpine Meadows in Northern Tibet, China

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Chinese Geographical Science 2014年第4期24卷 488-498页

作者： XIONG Dingpeng SHI Peili SUN Yinliang wu jianshuang ZHANG Xianzhou Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

Grazing exclusion is widely adopted in restoring degraded alpine grasslands on the Qinghai-Tibetan Plateau. However, its effectiveness remains poorly understood. In this study, we investigated the effects of grazing exclusion on plant productivity, species diversity and soil organic carbon （SOC） and soil total nitrogen （STN） storage along a transect spanning from east to west of alpine meadows in northern Tibet, China. After six years of grazing exclusion, plant cover, aboveground biomass （AGB）, belowground biomass （BGB）, SOC and STN were increased, but species diversity indices declined. The enhancement of AGB and SOC caused by grazing exclusion was correlated positively with mean annual precipitation （MAP）. Grazing exclusion led to remarkable biomass increase of sedge species, especially Kobresia pygmaea, whereas decrease of biomass in forbs and no obvious change in grass, leguminous and noxious species. Root biomass was concentrated in the near surface layer （10 cm） after grazing exclusion. The effects of grazing exclusion on SOC storage were confined to shallow soil layer in sites with lower MAP. It is indicated that grazing exclusion is an effective measure to increase forage production and enhance soil carbon sequestration in the studied region. The effect is more efficient in sites with higher precipitation. However, the results revealed a tradeoff between vegetation restoration and ecological biodiversity. Therefore, carbon pools recover more quickly than plant biodiversity in the alpine meadows. We suggest that grazing exclusion should be combined with other measures to reconcile grassland restoration and biodiversitv conservation.

关键词： aboveground biomass belowground biomass soil organic carbon (SOC) soil total nitrogen (STN) biodiversity grazingexclusion precipitation alpine meadow

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Hydrochemical characteristics and element contents of natural waters in Tibet, China

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Journal of Geographical Sciences 2015年第6期25卷 669-686页

作者： TIAN Yuan YU Chengqun LUO Kunli ZHA Xinjie wu jianshuang ZHANG Xianzhou NI Runxiang Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Xi'an University of Science and Technology Xi'an 710054 China

Sixty water samples （35 groundwater samples, 22 surface water samples and three hot-spring water samples） were collected at 36 points from villages and towns in Lhasa city, Nagchu （Nagqu） prefecture, Ali （Ngari） prefecture and Shigatse （Xigaze） prefecture （Tibet） in 2013 to study the hydrochemical characteristics and element contents of natural waters. The concentrations of elements were determined in the water samples and compared with the concentrations in water samples from other regions, such as southeast Qinghai, south Xinjiang, east Sichuan and west Tibet. The hydrochemical species in different areas were also studied. Water in most parts of Tibet reaches the requirements of the Chinese national standard and the World Health Organization international standard. The pH values of the water samples ranged from 6.75 to 8.21 and the value for the mean total dissolved solids was 225.54 mg/L. The concentration of arsenic in water from Ali prefecture exceeded the limit of both the Chinese national standard and the international standard and the concentration of fluoride in water from Shuanghu exceeded the limit of both the Chinese national standard and the international standard. The main hydrochemical species in water of Tibet is Ca （HCO3）2. From south to north, the main cation in water changes from Ca^2＋ to Na^＋, whereas the main anions in water change from HCO3^- to Cl^- and SO4^2-. The chemistry of river water and melt water from ice and snow is dominated by the rocks present at their source, whereas the chemistry of groundwater is affected by many factors. Tectonic divisions determine the con- centrations of the main elements in water and also affect the hydrochemical species present.

关键词： element concentrations hydrochemical species water chemistry water quality Tibet

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Impact of Cloud on Net Ecosystem CO2 Exchange of Alpine Meadow in Tibetan Plateau

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 69-75页

作者： Fan Yuzhi Zhang Xianzhou Shi Peili wu jianshuang Institute of Geographic Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Meteorological elements and CO2 fluxes over alpine meadow ecosystem were observed continuously from 2004 to 2005 in Damxung Alpine Meadow Flux Station, China Flux Network. Based on the eddy covariance CO2 fluxes and meteorological data obtained, the relationships among the CO2 fluxes, the cloud amount, and the meteorological factors in alpine meadow ecosystem were explored and analyzed. Some conclusions can be drawn from the discussion with previous researches as following：（1） the cloud amount can affect the net ecosystem CO2 exchange （NEE） of alpine meadow on Tibetan Plateau; （2） the soil temperature sensitive to the cloud amount, is a major environmental controlling factor for NEE, and closely relates to the maximum of NEE. In the moming period with large cloud amount, the NEE reaches its maximum when the clearness index ranges from 0.5 to 0.7; yet in the afternoon it comes to the maximum with the index from 0.2 to 0.35. The span of soil temperature covers from 12 to 15℃ as the NEE at its highest; （3） the scatterplots between NEE and photosynthetic available radiation （PAR） was a significant inverse triangle in the clear day, two different kinds of concave curves in the cloudy day, and strongly convergent rectangular hyperbola in the overcast day. These differences were controlled by the changes of light radiation and soil temperature.

关键词： net ecosystem CO2 exchange cloud amount clearness index alpine meadow ecosystem Tibetan Plateau

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Effects of livestock exclusion and climate change on aboveground biomass accumulation in alpine pastures across the Northern Tibetan Plateau

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Chinese Science Bulletin 2014年第32期59卷 4332-4340页

作者： jianshuang wu Xianzhou Zhang Zhenxi Shen Peili Shi Chengqun Yu Baoxiong Chen Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

To better understand the ecological and economic benefits of short-term grazing exclusion on the aboveground net primary productivity(ANPP)of alpine pastures,we conducted annual multi-site transect surveys in the summers from 2009 to 2011 and calculated the aboveground biomass discrepancy(ABD)between grazed and ungrazed pastures at plant community and economic group levels for three zonal alpine grassland types—meadow,steppe,and desert-steppe—across the northern Tibetan *** results indicated that aboveground biomass(AGB)significantly differed among grassland types and declined northwesterly from 64.07 to11.44 g m-2with decreasing precipitation and increasing *** mean ABD exhibited considerable community dependency,with meadow(12.47 g m-2)[steppe(6.91 g m-2)[desert steppe(2.54 g m-2),and it declined from 25.42 to 1.29 g m-2with decreasing precipitation and increasing temperature.‘Good forage’,*** and sedges,benefited most from grazing exclusion,followed by edible *** longer grazing exclusion durations(GEDs),the aboveground biomass of poisonous locoweeds initially decreased and then increased compared with the adjacent grazed *** the nested analysis of co-variances with a general linear model,growing season precipitation(GSP;from May to September)accounted for 52.67%ofthe observed variation in AGB,followed by AGT(9.77%)and pasture management systems(PMSs;grazing or grazing-excluded,5.31%).The variation in ABD was explained primarily by AGT(16.52%),GED(20.25%),and the interaction of AGT 9 GED(19.58%).Our results confirm that precipitation is the primary factor controlling the ANPP of alpine grasslands on the Northern Tibetan Plateau and that the ecological benefits arising from grazing exclusion are also partly dependent on grassland type and exclusion ***,spatial and temporal variations in growing season precipitation and plant functional traits or economic group composition should be jointly considered when devel

关键词：地上生物量藏北高原生物量积累牧场高山气候变化荒漠草原牲畜

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Comparison of Methods for Evaluating the Forage-livestock Balance of Alpine Grasslands on the Northern Tibetan Plateau

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Journal of Resources and Ecology 2020年第3期11卷 272-282页

作者： CAO Yanan wu jianshuang ZHANG Xianzhou NIU Ben HE Yongtao School of Earth Science and Engineering Hebei University of EngineeringHandan 056038HebeiChina Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Livestock grazing is one of primary way to use grasslands throughout the world, and the forage-livestock balance of grasslands is a core issue determining animal husbandry sustainability. However, there are few methods for assessing the forage-livestock balance and none of those consider the dynamics of external abiotic factors that influence forage yields. In this study, we combine long-term field observations with remote sensing data and meteorological records of temperature and precipitation to quantify the impacts of climate change and human activities on the forage-livestock balance of alpine grasslands on the northern Tibetan Plateau for the years 2000 to 2016. We developed two methods: one is statical method based on equilibrium theory and the other is dynamic method based on non-equilibrium theory. We also examined the uncertainties and shortcomings of using these two methods as a basis for formulating policies for sustainable grassland management. Our results from the statical method showed severe overgrazing in the grasslands of all counties observed except Nyima(including Shuanghu) for the entire period from 2000 to 2016. In contrast, the results from the dynamic method showed overgrazing in only eight years of the study period 2000–2016, while in the other nine years alpine grasslands throughout the northern Tibetan Plateau were less grazed and had forage surpluses. Additionally, the dynamic method found that the alpine grasslands of counties in the northeastern and southwestern areas of the northern Tibetan Plateau were overgrazed, and that alpine grasslands in the central area of the plateau were less grazed with forage surpluses. The latter finding is consistent with field surveys. Therefore, we suggest that the dynamic method is more appropriate for assessment of forage-livestock management efforts in alpine grasslands on the northern Tibetan Plateau. However, the statical method is still recommended for assessments of alpine grasslands profoundly di

关键词： aboveground biomass alpine grasslands carrying capacity forage-livestock balance Northern Tibetan Plateau

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面向大规模多类别的病虫害识别模型

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农业工程学报 2022年第8期38卷 169-177页

作者：温长吉王启锐陈洪锐吴建双倪军杨策苏恒强吉林农业大学信息技术学院长春130118 南京农业大学农学院南京210095 明尼苏达大学食品、农业与自然资源科学学院圣保罗55108 吉林农业大学智慧农业研究院长春130118

早期病虫害精准识别是预警和防控的关键,但是病虫害种类繁多数量巨大,外部形态存在类间相似度较高而类内差异性较大等性状特征,导致病虫害识别仍然是一项极具挑战的工作。为实现病虫害识别分类任务中差异化特征的提取和表示,该研究提出... 详细信息

早期病虫害精准识别是预警和防控的关键,但是病虫害种类繁多数量巨大,外部形态存在类间相似度较高而类内差异性较大等性状特征,导致病虫害识别仍然是一项极具挑战的工作。为实现病虫害识别分类任务中差异化特征的提取和表示,该研究提出一种大规模多类别精细病虫害识别网络模型(a large-scale multi-category fine-grained pest and disease network,PD-Net)。首先通过在基准网络模型中引入卷积块注意力模型,通过混合跨特征通道域和特征空间域实现模型在通道和空间两个维度上对关键特征提取和表示,用以增强网络对差异化特征的提取和表示能力。其次引入跨层非局部模块,提升模型在多个特征提取层之间对于多尺度特征的融合。在61类病害数据集和102类虫害数据集上的试验结果表明,对比AlexNet、VGG16、GoogleNet、Inception-v3、DenseNet121和ResNet50模型,该研究提出的面向大规模多类别病虫害识别模型,Top1识别准确率在病害和虫害集上分别达到88.617%和74.668%,精确率分别达到了0.875和0.745,召回率分别达到0.874和0.738,F1值达到0.874和0.732,试验结果对比其他模型均有一定幅度的提升,验证了PD-Net模型在大规模多类别病虫害识别上的有效性。

关键词：模型深度学习病虫害精细分类卷积块注意力模块跨层非局部模块

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Geographical and Botanical Variation in Concentrations of Molybdenum in Natural Pasture Plants and Surface Water and Yak Molybdenum Ingestion in North Tibet,China

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Journal of Resources and Ecology 2018年第5期9卷 545-553页

作者： TIAN Yuan YU Chengqun ZHA Xinjie wu jianshuang GAO Xing FENG Chujian Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Ministry of Science and Technology of the People＇s Republic of China Beijing 100862China

The North Tibet plateau is the world highest plateau with a unique alpine grassland and water environment. To obtain a better understanding of the correct supply of Molybdenum（Mo） to livestock in north Tibet,we investigated the content and geographical variation of Mo in different families of pasture plants（n=1017） and water（n=40）,then discuss the Cuprum（Cu）：Mo ratio in different plant families,and calculate the total Mo intake of the yak in north Tibet. The average Mo concentration in five families preferred for grazing are： Compositae（2.71 μg g^（-1））,Leguminosae（2.70 μg g^（-1））,Gramineae（2.48 μg g^（-1））,Cyperaceae（1.63 μg g^（-1））,and Rosaceae（1.51 μg g^（-1））. There was a strong geographical variation in Mo concentration（p 0.001）. The mean value of Mo in north Tibet surface water from 15 sites is 0.89 μg L^（-1）. The Mo ingestion by yak through these plants and water in north Tibet is about 9586 μg day^（-1） which means the toxicity of Mo does not exist in the average daily diet. However,the large geographical variation found may cause some toxicity of Mo in the average daily intake of north Tibet pasture plants in some areas. The Cu：Mo ratio of 2：60 is considered the limit for risk of Mo hyperactivity,while extremely high Cu：Mo ratios may lead to chronic copper poisoning. Our survey of plant samples found 43.29% below and 29.3% above the limiting Cu：Mo ratio of 60 indicating some risk to north Tibet livestock.

关键词： North Tibet pasture plants water molybdenum copper

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围封对藏北高寒草原土壤矿质元素和群落特征的影响

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草业科学 2022年第4期39卷 645-659页

作者：郭晨睿杨敬坡李少伟牛犇马娇林武建双河北科技大学环境科学与工程学院河北石家庄050018 中国农业科学院农业环境与可持续发展研究所北京100081 中国科学院地理科学与资源研究所北京100101 西藏自治区畜牧总站西藏拉萨850000

围栏封育是退化草地生态恢复的常见措施之一。土壤矿质元素含量影响植物个体生长发育和群落结构功能演替。为评价围栏封育对高寒草原土壤矿质元素和植物群落特征的影响,本研究于2010–2013年夏季对班戈县北拉镇和普保镇2块样地(围栏内外... 详细信息

围栏封育是退化草地生态恢复的常见措施之一。土壤矿质元素含量影响植物个体生长发育和群落结构功能演替。为评价围栏封育对高寒草原土壤矿质元素和植物群落特征的影响,本研究于2010–2013年夏季对班戈县北拉镇和普保镇2块样地(围栏内外)进行植物和土壤采样,测定群落水平植物物种多样性、地上生物量以及表层土壤Ca、Cu、Fe、Mg、Mn和Zn含量。结果显示:1) 5~8年围栏封育只显著降低了北拉镇样地土壤Ca、Mg和Cu含量(P 0.05)。2)围栏封育只显著提高了普保镇样地地上生物量(P 0.05)。3)方差分析结果显示,仅土壤Mg含量与地上生物量显著相关(P 0.05)。综上所述,短期围栏封育对高寒草原土壤矿质元素和植物群落的恢复的影响有限。

关键词：地上生物量高寒草原围栏禁牧微量养分矿质元素

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