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Shallow groundwater quality changes as results of agricultural activities
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《Global Geology》 1998年第1期30-31,共2页
关键词 Shallow groundwater quality changes as results of agricultural activities
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Regional Characteristics and Causes of Haze Events in Northeast China 被引量:8
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作者 CHEN Weiwei ZHANG Shichun +5 位作者 TONG Quansong ZHANG Xuelei ZHAO Hongmei MA Siqi XIU Aijun HE Yuexin 《Chinese Geographical Science》 SCIE CSCD 2018年第5期836-850,共15页
Northeast China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. However, the underlying forces driving haze formation during different seasons are poorly understood. In ... Northeast China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. However, the underlying forces driving haze formation during different seasons are poorly understood. In this study, we explored the spatio-temporal characteristics and causes of haze events in Northeast China by combining a range of data sources(i.e., ground monitoring, satellite-based products, and meteorological products). It was found that the ‘Shenyang-Changchun-Harbin(SCH)'city belt was the most polluted area in the region on an annual scale. The spatial distribution of air quality index(AQI) values had a clear seasonality, with the worst pollution occurring in winter, an approximately oval-shaped polluted area around western Jilin Province in spring, and the best air quality occurring in summer and most of the autumn. The three periods that typically experienced intense haze events were Period I from mid-October to mid-November(i.e., late autumn and early winter), Period II from late-December to February(i.e., the coldest time in winter), and Period III from April to mid-May(i.e., spring). During Period I, strong PM_(2.5) emissions from seasonal crop residue burning and coal burning for winter heating were the dominant reasons for the occurrence of extreme haze events(AQI > 300). Period II had frequent heavy haze events(200 < AQI < 300) in the coldest months of January and February, which were due to high PM_(2.5) emissions from coal burning and vehicle fuel consumption, a lower atmospheric boundary layer, and stagnant atmospheric conditions. Haze events in Period III, with high PM_(10) concentrations, were primarily caused by the regional transportation of windblown dust from degraded grassland in central Inner Mongolia and bare soil in western Jilin Province. Local agricultural tilling could also release PM_(10) and enhance the levels of windblown dust from tilled soil. Better control of coal burning, fuel consumption, and crop residue burning in winter and autumn is urgently needed to address the haze problem in Northeast China. 展开更多
关键词 air quality PM10 PM2.5 dust agricultural activity coal burning fuel consumption
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Accounting Practice in Agricultural Enterprises in Turkey
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作者 Esin Yelgen Suleyman Uyar Alanya Alaaddin Keykubat University +1 位作者 Alanya Turkey 《Chinese Business Review》 2017年第7期316-326,共11页
Agricultural sector is vital for human beings, it provides stuffto the other sectors and it contributes to employment considerably. A large proportion of the exportation of Turkey is made from the agricultural product... Agricultural sector is vital for human beings, it provides stuffto the other sectors and it contributes to employment considerably. A large proportion of the exportation of Turkey is made from the agricultural products. Thereby it can be said that the agricultural sector is one of the main sectors contributing to the economy of the country considerably. But it's known that the sector is affected by some risks and uncertainities such as: sector's being made-up of family-owned companies, its being sensitive to the weather conditions, the long process of buying products, the work's being seasonal, self-consumption, the difficulty in accounting the cost, unrecorded agricultural transactions. Within this context to determine the sector's contribution to the country's economy clearly is related to recording the agricultural transactions properly and choosing the realistic methods and implementations. But despite the importance that agricultural transactions carry, the rules of recognition of the related transactions stay at an area that is not much worked on by the operators and researchers till the accounting postulates published. One reason for this is the sector, which is generally made-up of family-owned companies, and the operators have a general view point that accounting is not the purpose of management but taxation. In recent years with the international development of economy and technology, it's seen that big investors have entered the sector. With the changed system of trade, agricultural sector became a strategic sector. In this respect, in-depth data and information, acquired from accounting system, became very important. In this study, the principles and the rules that are applied in the agricultural transactions within the frame of international accounting standards are explained. In which account group should be the biological assets that are agricultured and agricultural products according to their qualities, which accounts are used, and how they are recognitioned are explained. In this context, in the study the examples which are related with the implementation are given over annual plants and prennial plants. The differences between the accounts that are used, are mentioned over by these examples. 展开更多
关键词 agricultural activities accounting standards TMS 41 valuation of biological assets depreciation ofbiological assets TURKEY
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Examination of Surface Water Along River-Rima Floodplain in Wamakko, Sokoto State, Nigeria
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作者 Abdulqadir Abubakar Usman Murtala Abubakar Gada +2 位作者 Aminu Muhammad Bayawa Ibrahim Mustapha Dankani Saadu Umar Wali 《Journal of Geological Research》 2020年第3期43-51,共9页
This study examined the hydrochemistry of surface water along the River-Rima floodplain area.Five sampling locations were purposively selected,and,in each point,three samples were taken from surface water(river).The s... This study examined the hydrochemistry of surface water along the River-Rima floodplain area.Five sampling locations were purposively selected,and,in each point,three samples were taken from surface water(river).The sampling was repeated after 20 days.Thus,a total of 30 samples were collected.Water samples obtained were subjected to laboratory tests.Results revealed that BOD,TDS,Mg2+,and Fe3+are above the World Health Organization(WHO)and Standard Organization of Nigeria(SON)reference guidelines for drinking water quality.Isolates detected from the coliform bacteriological analysis include Enterobacter aerogene,Escherichia coli,and Citrobacter freundii with most of the samples showing coliform bacteria growth above the SON standard for drinking water.Hence,the water in the River-Rima floodplain of the Wamakko area is of low quality and unsafe for drinking.Results of principal component analysis(PCA)revealed external influences such as pollutant wash off and rock weathering as controls on hydrochemistry of surface water.There is some indication of anthropogenic inputs(Cl-,NO3-,and PO42-)based on hierarchical cluster analysis.Elements including Cl-,NO3-,and PO42-are increasingly added into surface water from human activities,mainly agriculture,and municipal sewage. 展开更多
关键词 Surface water pollution Agricultural activities Bacteriological analysis
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Enhancement of beneficial microbiomes in plant-soil continuums through organic fertilization:Insights into the composition and multifunctionality
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作者 Wen-Jing Li Xin-Yuan Zhou +4 位作者 Xin-Li An Li-Juan Li Chen-Shuo Lin Hua Li Hong-Zhe Li 《Soil Ecology Letters》 CSCD 2024年第3期109-120,共12页
Soil microbiomes play a crucial role in maintaining ecological functions and are of great importance for soil health.Some of them could bring benefits to plants for growth promotion.Despite numerous studies have focus... Soil microbiomes play a crucial role in maintaining ecological functions and are of great importance for soil health.Some of them could bring benefits to plants for growth promotion.Despite numerous studies have focused on specific beneficial bacteria and their interactions with soils and plants,we still lack a comprehensive understanding of beneficial communities in plant–soil continuums and their responses to agricultural activities.To address this gap,we carried out a microcosm experiment using 16S rRNA amplicon sequencing to explore the effects of organic fertilization on beneficial communities in plant–soil continuums and assess their potential multifunctionality.Our findings reveal that organic fertilization had a positive impact on the beneficial functionality of bacterial communities in plant–soil continuums.This improvement was primarily attributed to the optimized soil physicochemical conditions resulting from organic fertilization.Additionally,organic fertilization increased the complexity of bacterial co-occurrence networks in both soils and the endosphere.Keystone taxa in the endosphere undergone a shift of functions toward pathogen suppression as the result of organic fertilization.Furthermore,this study revealed that plants exhibited a preference for internalizing beneficial bacteria over other type of bacteria.We also provided new insights for evaluating the multifunctionality of microbiomes,and found that the functionality of beneficial communities in plant–soil continuums is enhanced by organic fertilization.All these findings suggested that organic fertilization can be an effective strategy for maintaining plant and soil health. 展开更多
关键词 plant–soil continuums beneficial bacteria agricultural activities multifunctionality endosphere
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New progress in the Holocene climate and agriculture research in China 被引量:18
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作者 LI XiaoQiang 《Science China Earth Sciences》 SCIE EI CAS 2013年第12期2027-2036,共10页
Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change an... Global climate change and its possible ecological consequences have become the focused issue(IPCC,2007;Mann et al.,2008;Ding et al.,2009).The Holocene contains the analogous characteristic of future climatic change and the continuous agriculture activity,providing the ideal"similar pattern"for studying the climate change and human adaption and impact in the future.Based on the recent studies of stalagmite,ice core,ocean,and lake etc.,the paper introduces the new progress in the Holocene climate and agriculture research in China as follows:(1)Discuss the variability,amplitude,and unstable characteristic of climate,as well as the abrupt events and mechanisms of climate.(2)Analyze the botanical index records for studying the early agriculture.(3)Review the agricultural origin,expanding,and development.(4)Reveal the style and intensity of early agriculture and understand the agricultural impact and adaption to the environmental changes.(5)Introduce ongoing research projects in China and emphasize the significance of increasing the dating precision and the indicative effectiveness of proxies.(6)Realize how the ecosystem and environmental factors respond to the increasing temperature process,understand how the human adapt to the rapid climate change,and provide the scientific basis for assessing the effects of climate change and the human adaption in the future. 展开更多
关键词 China HOLOCENE climate change agriculture activity new progress
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A water quality analysis system to evaluate the impact of agricultural activities on N outflow in river basins in Japan 被引量:1
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作者 Makoto Takeuchi Sunao Itahashi Masanori Saito 《Science China(Life Sciences)》 SCIE CAS 2005年第z1期100-109,共10页
We have developed a personal-computer-based water quality analysis system for river basins. The system estimates potential N outflow by model and calculates actual N outflow from monitoring data. For the former it use... We have developed a personal-computer-based water quality analysis system for river basins. The system estimates potential N outflow by model and calculates actual N outflow from monitoring data. For the former it uses the potential load factor method to estimate annual nitrogen load from various sources and runoff potential from each area of land in a basin. For the latter it analyzes water quality monitoring data in relation to meteorological data. We used the system to analyze N outflow in basins around Lake Kasumigaura and the Yahagi River in central Honshu, Japan. The land around Lake Kasumigaura is rather flat, and about 25% is periodically flooded for rice and lotus cultivation. The land around the Yahagi River is mountainous, and much less land is flooded. In the Yahagi River basin the actual N outflow agreed closely with the potential. However, the actual N outflow in the basin around Lake Kasumigaura was much less than the potential, suggesting that a large part of the N load is denitrified in flooded soils. This further indicates that a sequence of different land uses including flooded rice fields is an important factor determining N outflow in basins in Japan. On the basis of the above analyses, we incorporated a denitrification model into the system that enables us to estimate N balance in a designated basin;this system may be helpful in the formulation of scenarios of land use andsoil management for improving water quality. 展开更多
关键词 A water quality analysis system to evaluate the impact of agricultural activities on N outflow in river basins in Japan
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Process analysis and mitigation strategies for wetland degradation caused by increasing agricultural water demand:an ecology-economy nexus perspective
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作者 Lin Jiang Hui Wang +1 位作者 Saige Wang Wen Zhang 《Ecological Processes》 SCIE EI CSCD 2023年第1期560-572,共13页
Background Farmland expansion has played a major role in wetland degradation in Heilongjiang Province,China in recent decades.Farmland expansion increases the demands for water,thereby affecting wetland water cycles,a... Background Farmland expansion has played a major role in wetland degradation in Heilongjiang Province,China in recent decades.Farmland expansion increases the demands for water,thereby affecting wetland water cycles,and promoting the shrinkage of wetland areas and degradation of ecosystem functions.As an open system,agricultural production is limited by both ecological and socioeconomic conditions.However,our understanding of wetland degradation caused by farmland expansion from the perspective of the ecology-economy nexus is limited.Methods A correlation between farmland expansion and agricultural economic activities was established,and wetland degradation driven by agroeconomic activities was inversely derived using a multi-regional input-output(MRIO)analysis.We developed an ecology-economy nexus framework to explore the ecological process of the area and water demand tradeoffs between wetland degradation and farmland expansion,the economic process of wetland degradation driven by food consumption,and the nexus between the two processes.We finally explored strategies to mitigate wetland degradation due to increased agricultural water demand.Results Farmland expansion contributed to 93.76%of the total degraded wetland area.There was a significant negative correlation between wetland area and the water consumption for crop production,but no significant correlation between wetland area and the ecological footprint of croplands.The direct wetland degradation caused by local final demand accounted for 63.02%,while the indirect degradation caused by non-local final demand accounted for 36.98%.Hebei,Shandong,Liaoning,Inner Mongolia,and Shanghai were the top five provinces contributing to indirect wetland degradation in Heilongjiang.Our findings indicated that a mixed scenario combining water footprint reduction per unit yield with food export reduction could maximize wetland restoration while reducing local farmland-wetland competition for water.Conclusions Our research highlights the effects of economic processes in the agricultural sector on wetland degradation,and showed that the adjustment of food trade patterns can effectively promote wetland restoration. 展开更多
关键词 Agricultural economic activities Farmland expansion Water footprint Wetland degradation Wetland restoration
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