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Tracing suspended and bed sediments during high and low water periods using geochemical characteristics-Case study:Vazrood watershed,northern Iran

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Journal of Mountain Science 2024年第2期21卷 470-483页

作者： KARIMI Nabiyeh GHOLAMI Leila KAVIAN Ataollah KHALEDI DARVISHAN Abdulvahed Department of Watershed Management Faculty of Natural ResourcesSari Agricultural Sciences and Natural Resources UniversitySari ***Iran Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Iran

Complete and comprehensive information about sediment dynamic and identification of hotspots of sediment production and transport are necessary for understanding the erosion processes and increasing the efficiency of soil and water conservation *** studies used the sediment fingerprint techniques to investigate the contribution of different sources in suspended and bed sediment yield of the ***,the contribution of various land use/land covers in suspended and bed sediment yield for the great Caspian Sea basin is in an aura of ambiguity and the present study was conducted to gather information about an important part of this area in northern Iran,where rangelands are located upstream of Hyrcanian forests and dense agricultural lands are located *** surface soil of different land use/land covers including forest,rangeland,agriculture and streambank lands were sampled in 30 *** and bed sediments were sampled in the watershed outlet in two high and low water *** characteristics of soil and sediment samples containing 59 elements were measured using ICP-OES GBC *** reliable and suitable tracers from 59 elements were then selected using Range test,Kruskal-Wallis and Discriminant Function Analysis,respectively,in FingerPro package of R *** results showed that for suspended sediment,streambank and rangeland had the highest contributions of 86.2%and 47.5%,respectively,in two high and low water *** bed sediment,in two high and low water periods,rangeland and streambank had the highest contributions of 73.8%and 84.4%,*** use change and especially human activities such as agriculture,road construction and development of residential areas along the main river riparian zone has led to a significant increase in suspended and bed sediments.

关键词： Caspian Sea basin FingerPro Geochemistry Sediment transport Tracer combination

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Development of Machine Vision-Based Algorithm for Counting and Discriminating Filled and Unfilled Paddy Rice in Overlapping Mode

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Rice science 2024年第5期31卷 503-506,I0021-I0028页

作者： Mahdieh HOSEINGHOLIZADEH-ALASHTI Davood KALANTARI Department of Biosystems Engineering Faculty of Agricultural EngineeringSari Agricultural Sciences and Natural Resources UniversityP.O.Box 578Iran

In this study, a new method based on image processing was presented to count and discriminate paddy rice, even when they overlapped. This method was performed in three steps. In the first step, using a reference image that excludes any overlapping paddy rice, the average area, standard deviation, and a threshold value for paddy rice were determined.

关键词： paddy filled steps

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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh Department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Soybean(Glycine max)rhizosphere organic phosphorus recycling relies on acid phosphatase activity and specific phosphorusmineralizing-related bacteria in phosphate deficient acidic soils

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Journal of Integrative Agriculture 2024年第5期23卷 1685-1702页

作者： Qianqian Chen Qian Zhao Baoxing Xie Xing Lu Qi Guo Guoxuan Liu Ming Zhou Jihui Tian Weiguo Lu Kang Chen Jiang Tian Cuiyue Liang Root Biology Center State Key Laboratory for Conservation and Utilization of Subtropical Agro-BioresourcesCollege of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China College of natural resources and Environment South China Agricultural UniversityGuangzhou 510642China Henan Academy of Crops Molecular Breeding Henan Academy of Agricultural SciencesZhengzhou 450002China

Bacteria play critical roles in regulating soil phosphorus(P) cycling. The effects of interactions between crops and soil P-availability on bacterial communities and the feedback regulation of soil P cycling by the bacterial community modifications are poorly understood. Here, six soybean(Glycine max) genotypes with differences in P efficiency were cultivated in acidic soils with long-term sufficient or deficient P-fertilizer treatments. The acid phosphatase(AcP) activities, organic-P concentrations and associated bacterial community compositions were determined in bulk and rhizosphere soils. The results showed that both soybean plant P content and the soil AcP activity were negatively correlated with soil organic-P concentration in P-deficient acidic soils. Soil P-availability affected the ɑ-diversity of bacteria in both bulk and rhizosphere soils. However, soybean had a stronger effect on the bacterial community composition, as reflected by the similar biomarker bacteria in the rhizosphere soils in both P-treatments. The relative abundance of biomarker bacteria Proteobacteria was strongly correlated with soil organic-P concentration and AcP activity in low-P treatments. Further high-throughput sequencing of the phoC gene revealed an obvious shift in Proteobacteria groups between bulk soils and rhizosphere soils, which was emphasized by the higher relative abundances of Cupriavidus and Klebsiella, and lower relative abundance of Xanthomonas in rhizosphere soils. Among them, Cupriavidus was the dominant phoC bacterial genus, and it was negatively correlated with the soil organic-P concentration. These findings suggest that soybean growth relies on organic-P mineralization in P-deficient acidic soils, which might be partially achieved by recruiting specific phoCharboring bacteria, such as Cupriavidus.

关键词： organic phosphorus acid phosphatase soybean bacterial community phoC-harboring bacteria rhizosphere

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Carrying Capacity and Coupling Coordination of Water and Land resources Systems in Arid and Semi-arid Areas: A Case Study of Yulin City, China

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Chinese Geographical Science 2024年第5期34卷 931-950页

作者： ZHANG Qianxi CAO Zhi WANG Yongsheng HUANG Yijia Institute of Geographic sciences and natural resources Research Chinese Academy of SciencesBeijing 100101China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development *** this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to *** findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland ***,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of ***,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning ***,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern *** the water resources endowment is vital for the highly efficient use of water and land resources.

关键词： water and land resources systems carrying capacity coupling coordination human-earth system sustainable development Yulin City,China

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Spatial-temporal patterns and evolution of carbon storage in China's terrestrial ecosystems from 1980 to 2020

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Science China Earth sciences 2024年第10期67卷 3270-3287页

作者： Shaojian WANG Shijie ZHOU Chuanglin FANG School of Geography and Planning Sun Yat-sen University Institute of Geographic sciences and natural resources Research Chinese Academy of Sciences

Analyzing the changes in carbon storage in terrestrial ecosystems caused by land use changes is a crucial part of exploring the carbon cycle. In addition, enhancing carbon storage in terrestrial ecosystems is an effective and environmentally friendly measure to sequester anthropogenic carbon emissions, which is significant for achieving carbon neutrality and curbing global climate change. This paper uses land use data and carbon density tables with the In VEST model to obtain a carbon storage distribution map of China. It further applies land use response elasticity coefficients, Theil index multi-stage nested decomposition, and spatial autocorrelation analysis to examine the spatial-temporal patterns, causes of changes, and evolution characteristics of carbon storage in terrestrial ecosystems from 1980 to 2020. The results show that the temporal changes in China's carbon storage generally present an inverted S-curve, with an initial rapid decline followed by a slower decrease. Spatially, it features high levels in the northeast, low levels in the northwest, and a uniform distribution in the central and southern *** disturbance of land use type changes on terrestrial ecosystem carbon storage has been effectively mitigated. The significant reduction in grassland area in the Southwest region is the main source of carbon storage loss during the study period, and the encroachment of construction land on arable land in large urban agglomerations is one of the important causes of carbon storage loss. The Theil index multi-stage nested decomposition results indicate that the overall difference in carbon storage in China has decreased, while differences among cities within provinces and among counties within cities have increased. The influence of natural factors on the distribution of carbon storage is weakening, whereas the impact of human activities is becoming more profound, enhancing its influence on the spatial distribution of carbon storage in China. From 198

关键词： Terrestrial ecosystem carbon storage Carbon density Land use change InVEST model Spatiotemporal pattern

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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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Patterns and drivers of seasonal water sources for artificial sand-fixing plants in the northeastern Mu Us sandy land,Northwest China

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Pedosphere 2024年第1期34卷 63-77页

作者： Yanwu PEI Laiming HUANG Ming'an SHAO Jiao WANG Yinglong ZHANG Yellow River Delta Modern agricultural Engineering Laboratory Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of natural resources and Environment Northwest Agriculture and Forestry UniversityYangling 712100China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences of Chinese Academy of SciencesBeijing 100085China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China Shenmu Ecological Association Shenmu 719399China

Understanding plant water-use patterns is important for improving water-use efficiency and for sustainable vegetation restoration in arid and semi-arid regions. However, seasonal variations in water sources and their control by different sand-fixing plants in water-limited desert ecosystems remain poorly understood. In this study, stable isotopic ratios of hydrogen(δ^(2)H) and oxygen(δ^(18)O) in precipitation, soil water, groundwater, and xylem water were determined to document seasonal changes in water uptake by three representative plant species(Pinus sylvestris var. mongolica Litv., Amygdalus pedunculata Pall., and Salix psammophila) in the northeastern Mu Us sandy land, Northwest China. Based on the depth distribution and temporal variation of measured gravimetric soil water content(SWC), the soil water profile of the three species stands was divided into active(0.01 g g^(-1)45%) layers. Annually, P. sylvestris, A. pedunculata, and S. psammophila obtained most water from deep(59.2%±9.7%, moist layer and groundwater),intermediate(57.4%±9.8%, stable and moist layers), and shallow(54.4%±10.5%, active and stable layers) sources, respectively. Seasonally, the three plant species absorbed more than 60% of their total water uptake from the moist layer and groundwater in the early(June) dry season;then, they switched to the active and stable layers in the rainy season(July–September) for water resources(50.1%–62.5%). In the late(October–November) dry season, P. sylvestris(54.5%–66.2%) and A. pedunculata(52.9%–63.6%) mainly used water from stable and moist layers, whereas S. psammophila(52.6%–70.7%) still extracted water predominantly from active and stable layers. Variations in the soil water profile induced by seasonal fluctuations in precipitation and groundwater levels and discrepancies in plant pheno

关键词： desert ecosystem MixSIAR model plant water uptake soil moisture stable isotopes vegetation restoration water-use efficiency

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Insights of carbon reduction practices from Winter Olympics 2022

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Science Bulletin 2024年第13期69卷 2034-2037页

作者： Xiaoyong Liao Shuai Zhong Jie Huang Zhu Liu Ayman Elshkaki You Li Lei Shen Yingli He Li An Yidong Zhu Wenhao Sun Tao Liang Jiaoe Wang Jinwei Dong Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory for resources Use and Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China university of Chinese Academy of sciences Beijing 100049China Department of Earth System Science Tsinghua UniversityBeijing 100084China

Concerns about the carbon emissions of mega-events revolve,mainly due to the impactful demonstration effects they ***,accurate monitoring of these emissions is crucial during such events[1].The Olympic and Paralympic Winter Games Beijing 2022(hereinafter“Winter Olympics 2022”)are recognized as the first Games to pay close attention to a wide range of emissions associated with all stages of the *** of emerging carbon reduction technologies,such as low-carbon materials and technologies,have shown promising effects on efforts to achieve carbon neutrality[2].The impacts of individual measures,such as Olympic infrastructure construction.

关键词： Winter emissions carbon

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Key processes of carbon cycle and sink enhancement paths in natural wetland ecosystems in China

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Science China Earth sciences 2024年第8期67卷 2444-2459页

作者： Jinshuai LI Tianxiang HAO Meng YANG Guirui YU Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration ***,the key carbon cycle processes in wetland ecosystems still lack a systematic *** the context of wetland protection and restoration,there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland *** this paper,the key processes of carbon cycle,such as photosynthetic carbon uptake,microbial carbon decomposition and carbon deposition and burial,are sorted out and summarized in four major wetland types,namely,swamp and peat wetlands,river and riparian wetlands,lake and lakeshore wetlands,and estuarine and coastal *** on the key processes of carbon cycle,three technological pathways for carbon sink multiplication are proposed,including,vegetation carbon sequestration and sink enhancement technology,soil carbon emission reduction technology and carbon deposition and burial *** key technologies under each pathway are further *** the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively ***,wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in *** will provide a scientific basis for the strategy of doubling the carbon sinks of China′s wetland ecosystems.

关键词： Wetlands Carbon cycle Carbon sinks Technology pathways Conservation and restoration

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