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Economic Analysis of Pollution Caused by Animal Farming in China
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作者 周静 马友华 +2 位作者 栾敬东 刘鹏凌 张贵友 《Agricultural Science & Technology》 CAS 2014年第7期1219-1222,共4页
The research introduced pollution caused by animal farming on waters,agricultural lands,and atmosphere,as well as environment pollution and economic causes.Furthermore,a series of economic policies were proposed on pr... The research introduced pollution caused by animal farming on waters,agricultural lands,and atmosphere,as well as environment pollution and economic causes.Furthermore,a series of economic policies were proposed on preventing animal farming,such as definition of rights property,economic impetus and circular farming. 展开更多
关键词 Animal farming Environment pollution economic causes Prevention measures
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Land Use/Land Cover Change(LUCC) and Eco-Environment Response to LUCC in Farming-Pastoral Zone,China 被引量:33
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作者 HAO Hui-mei and REN Zhi-yuan College of Tourism and Environmental Science,Shaanxi Normal University,Xi’an 710062,P.R.China 《Agricultural Sciences in China》 CSCD 2009年第1期91-97,共7页
In order to understand land use/land cover changes (LUCC) and the eco-environment response to LUCC in farming- pastoral zone of the northern China during the recent twenty years, Baotou prefecture was selected as a ... In order to understand land use/land cover changes (LUCC) and the eco-environment response to LUCC in farming- pastoral zone of the northern China during the recent twenty years, Baotou prefecture was selected as a case study area for investigation and quantitative evaluation. Technologies of remote sensing (RS), global positioning system (GPS), geographic information system (GIS), and other statistical methods were employed to implement. Results showed that: (1) During the recent twenty years, the areas of forest lands, grasslands and water were reduced, whereas the areas of other types were enlarged. Parts of forest lands, grasslands, and waters had become farmlands, and about 31.5% of the changed grasslands transferred into unused lands. The newly increased farmlands mainly came from grasslands and unused lands. And the newly increased construction lands mainly came from grasslands and farmlands. (2) Regional eco- environmental quality decreased by 12.6%, for which the land degradation (especially the meadow degeneration) and the developing of the cultivated land were mainly responsible, and their contributions to the regional eco-environment changes were 51.84 and 23.63% respectively. (3) The tendency of LUCC and the eco-environment response to LUCC displayed spatial heterogeneity. It can be concluded that the present agricultural production mode was not sustainable in farming-pastoral zone of northern China. Land degradation, especially meadow degradation induced by over-trampling and overgrazing, and developing of cultivated land were mainly responsible for regional eco-environment deterioration. Changing the cultivated land to forest or grass, however, can relieve deterioration of local eco-environment to some extents. And in the farming-pastoral zone in the northern China, evaluating regional eco-environment responses to LUCC was very necessary due to its fragile eco-environments. 展开更多
关键词 farming-pastoral zone LUCC eco-environment responses to LUCC
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A comprehensive approach for assessing the economic contribution of forage and livestock improvement options to smallholder farming enterprises 被引量:1
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作者 Neil Mac Leod Scott Waldron WEN Shi-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第8期1573-1580,共8页
The importance of livestock production activities to improving the livelihoods of smallholder farming households and the efficiency of their underlying farming systems is increasingly recognized.A rapid increase in li... The importance of livestock production activities to improving the livelihoods of smallholder farming households and the efficiency of their underlying farming systems is increasingly recognized.A rapid increase in livestock numbers, especially beef cattle, and special purpose forages is being promoted for smallholder farms which have traditionally undertaken subsistence cropping activities or simple livestock rearing activities using low quality feedstuffs.Because limited plantings of specialized forages combined with a poor knowledge of animal nutrition are a challenge to establishing sustainable livestock enterprises, much public policy and research is now being focused on the use of new forages and improved feeding practices.A number of economic studies have suggested that specialized forage growing and livestock feeding activities can make a positive contribution to smallholder welfare.The studies have typically compared the total level of farm or household income with and without livestock activities.Little attention is given to how much the new forage or livestock activities actually contribute to or draw resources from other farm activities to assess their real economic contribution to the enterprise, and the availability of simple tools to assist in making such assessments are limited.This paper describes a simple modelling approach that was developed for an Australian Centre for International Agricultural Research(ACIAR)-supported project to explore the real as opposed to apparent economic impact of integrating improved forages and livestock within smallholder farming systems in the Red Soils region of south-central China.Application of the model is demonstrated using a simple case study of a smallholder enterprise that plans to introduce a new beef cattle rearing activity to its existing farm activity mix.The case study highlights the importance of explicitly valuing transfers of resources between different farm activities to gauge the real contribution of those activities to economic returns. 展开更多
关键词 smallholder farming systems ecoNOMICS resource transfers opportunity costs economic profit
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Smart Farming for Sustainable Rice Production:An Insight into Application,Challenge,and Future Prospect
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作者 Norhashila HASHIM Maimunah Mohd ALI +4 位作者 Muhammad Razif MAHADI Ahmad Fikri ABDULLAH Aimrun WAYAYOK Muhamad Saufi Mohd KASSIM Askiah JAMALUDDIN 《Rice science》 SCIE CSCD 2024年第1期47-61,共15页
Rice has a huge impact on socio-economic growth,and ensuring its sustainability and optimal utilization is vital.This review provides an insight into the role of smart farming in enhancing rice productivity.The applic... Rice has a huge impact on socio-economic growth,and ensuring its sustainability and optimal utilization is vital.This review provides an insight into the role of smart farming in enhancing rice productivity.The applications of smart farming in rice production including yield estimation,smart irrigation systems,monitoring disease and growth,and predicting rice quality and classifications are highlighted.The challenges of smart farming in sustainable rice production to enhance the understanding of researchers,policymakers,and stakeholders are discussed.Numerous efforts have been exerted to combat the issues in rice production in order to promote rice sector development.The effective implementation of smart farming in rice production has been facilitated by various technical advancements,particularly the integration of the Internet of Things and artificial intelligence.The future prospects of smart farming in transforming existing rice production practices are also elucidated.Through the utilization of smart farming,the rice industry can attain sustainable and resilient production systems that could mitigate environmental impact and safeguard food security.Thus,the rice industry holds a bright future in transforming current rice production practices into a new outlook in rice smart farming development. 展开更多
关键词 rice production smart farming food security agriculture sustainability
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Heavy Metal Pollution and Ecological Risk Assessment of Cultivated Land Soil in the Farming Areas of Coastal China:A Case Study of Donghai County,Jiangsu Province 被引量:2
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作者 Ligang LYU Xiaorui WANG +3 位作者 Xueyan SUI Zhenyu LIU Yong YUAN Chen LIN 《Agricultural Biotechnology》 CAS 2018年第6期125-129,共5页
Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their pot... Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their potential ecological risks in the topsoil( 0-20 cm) of cultivated land in Donghai County,a typical agricultural area along the Southeast Coast of China.The results showed that the average content of heavy metals in the cultivated soil of Donghai County was not over the risk screening values set in the Environmental Quality Standard for Soils.However,it was worth noting that in some of the sampling points,the content of Cr exceeded the risk screening value,and the standard exceeding points accounted for 24.74% of the total.In addition,the average content of Cr,Ni,As,Cd,Pb and Hg exceeded the soil background values of Jiangsu Province,and values for Cd,Cr and Pb were more than 1.5 times of the soil background value of Jiangsu Province.The heavy metals were at the medium integrated potential ecological risk level,and the potential ecological risk indices were high in the east and low in the west,and distributed in interlaced island shape.The potential ecological risk indices of the plains in the east were higher than those of the central gentle slope area and the western hillock area.The potential ecological risk was at a high level in Niushan Town which was situated the county center and in some regions with high urbanization levels. 展开更多
关键词 Heavy metal contamination CULTIVATED land ecoLOGICAL risk assessment farming area Donghai COUNTY
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Trace Metal Elements (Pb, Cd and As), 15N Nitrogen and Phosphorus Isotopes Accumulation in Three Varieties of Tomato from Conventional and Agro-Ecological Farming Systems in Burkina Faso 被引量:1
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作者 Christophe Dabiré Abdoulaye Sérémé +3 位作者 Hermann Panandtigri Abdoudramane Sanou W. D. B. Aimée Guissou Mamoudou H. Dicko 《Food and Nutrition Sciences》 2021年第2期194-205,共12页
Tomato is a market gardening product that plays an important nutritional and economic role in Burkina Faso. However, the bad use of pesticides for its production could have negative impacts </span><span style... Tomato is a market gardening product that plays an important nutritional and economic role in Burkina Faso. However, the bad use of pesticides for its production could have negative impacts </span><span style="font-family:Verdana;">consumers’</span><span style="font-family:Verdana;"> health. The objective of the present study was to assess the concentration of trace metal elements (Pb, Cd </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> As), 15N isotopes (</span></span><span style="font-family:Verdana;">NO<sub>2</sub><sup style="margin-left:-7px;">-</sup></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> NO<sub>3</sub><sup style="margin-left:-7px;">-</sup></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> NH<sub>4</sub><sup style="margin-left:-7px;">+</sup></span><span style="font-family:Verdana;">) and phosphorus (</span><span style="font-family:Verdana;">PO<sub>4</sub><sup style="margin-left:-7px;">2-</sup></span><span style="font-family:""><span style="font-family:Verdana;">) in tomatoes according to cultivation practices. Thus, three tomato varieties (Mon</span><span><span style="font-family:Verdana;">gal F1, F1 Cobra 26 </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Roma F1) were grown using organic and conventional production methods on 2 sites at Nongr Massom, (commune of Kadiogo province). The trace metal el</span></span><span style="font-family:Verdana;">ements were analyzed using atomic absorption spectrophotometry, the isotopes 15N (</span></span><span style="font-family:Verdana;">NO<sub>2</sub><sup style="margin-left:-7px;">-</sup></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> NO<sub>3</sub><sup style="margin-left:-7px;">-</sup></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> NH<sub>4</sub><sup style="margin-left:-7px;">+</sup></span><span style="font-family:Verdana;">) and phosphorus (</span><span style="font-family:Verdana;">PO<sub>4</sub><sup style="margin-left:-7px;">3-</sup></span><span style="font-family:Verdana;">) using standardized methods. Tomatoes from conventional agriculture had higher levels of trace metal elements (0.163</span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:Verdana;">0.298 mg/Kg, 0.082</span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.146 mg/Kg </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 0.018</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">0.032 mg/Kg respectively for Pb, Cd </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> As) than those from organic agriculture samples. </span><span style="font-family:Verdana;">Concentration</span><span style="font-family:Verdana;"> of trace metal</span></span><span style="font-family:Verdana;"> is</span><span style="font-family:""><span style="font-family:Verdana;"> lower for organic production with a reduction of 19.02%, 19.69% </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> 20.77% for Pb, Cd </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> As respectively compared to conventional production. High levels were recorded for the Roma F1 variety. The concentrations of trace metal elements in organic production are lower than the codex standards (2010) while those in conventional production are higher. These results could be due to the use of chemical inputs that could </span><span style="font-family:Verdana;">have a negative impact on</span><span style="font-family:Verdana;"> the nutritional quality of these tomatoes. The concentration of trace metal elements in tomato fruits is strongly correlated by production method and less by the variety (genetic). 展开更多
关键词 TOMATO Metal Trace farming Practices
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis Technical efficiency
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Dynamic Emission of CH<sub>4</sub>from a Rice-Duck Farming Ecosystem 被引量:1
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作者 Jia-En Zhang Ying Ouyang +1 位作者 Zhao-Xiang Huang Guo-Ming Quan 《Journal of Environmental Protection》 2011年第5期537-544,共8页
Global climatic change induced by emissions of greenhouse gases from human activities is an issue of increasing in-ternational environmental concerns, and agricultural practices and managements are the important contr... Global climatic change induced by emissions of greenhouse gases from human activities is an issue of increasing in-ternational environmental concerns, and agricultural practices and managements are the important contributors for such emissions. This study investigated dynamic emission of methane (CH4) from a paddy field in a rice-duck farming ecosystem. Three different cultivation treatments, namely the organic fertilizer + duck (OF+D), chemical fertilizer + duck (CF + D), and chemical fertilizer (Control) treatments, were employed in this study. Experimental data showed that hourly variations of CH4 emission from the paddy field during the day were somewhat positively correlated (R2 = 0.7 for the OF + D treatment and R2 = 0.6 for the CF+D treatment) to the hourly changes in air temperatures in addi-tion to the influences of the duck activities. The rate of CH4 emission for the CF+D treatment was higher than that of the Control treatment at the tillering stage, whereas the opposite was true at the heading stage. In contrary, the rate of CH4 emission for the OF + D treatment was always higher than that of the Control treatment regardless the tillering or heading stage. Our study revealed that the rate of CH4 emission depended not only on air temperature but also on the rice growth stage. A 6.7% increase in CH4 emission and in global warming potential (GWP) was observed for the CF + D treatment as compared to the Control treatment. This study suggested that although the impacts of duckling on the emission of CH4 depended on the rice growth stage and air temperature regime, the introduction of ducks into the rice farming system in general mitigated the overall CH4 emission and thereby the GWP. 展开更多
关键词 Methane EMISSION Global WARMING Potential Rice-Duck farming
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Contour Farming Suitability of the Black Soil Region in Northeast China and Its Spatial Characteristics
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作者 LI Yong ZHENG Shufeng +4 位作者 LIU Huanjun LUO Chong MENG Linghua WANG Yue WANG Liping 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1119-1133,共15页
Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique... Contour farming technology plays a key role in reducing soil erosion,enhancing water use efficiency,and fostering sustain-able agricultural development,Despite being a straightforward yet efficacious farming technique,it has not seen widespread implement-ation in China.Considering the deteriorating quality of arable lands in the Black Soil Region of Northeast China(BSR-NEC),it is ne-cessary to investigate spatial patterns and identify suitable areas for contour farming in this region.To achieve this objective,spatial autocorrelation and grouping analysis methods were employed to classify the land into four categories of suitability for contour farming:highly suitable,moderately suitable,generally suitable,and unsuitable.The results reveal that:1)the contour farming suitable area in BSR-NEC covers 89861.32 km^(2),accounting for 21.59%of arable land as of 2020.Heilongjiang Province owns the largest suitable area of 32853.68 km^(2),and Inner Mongolia has the highest proportion of 28.89%.2)In terms of the spatial distribution,regions with higher suitability for contour farming are concentrated in the Da Hinggan Mountains region,particularly Nenjiang City(Heilongjiang Province),which has the highest area of 2593.07 km^(2).Areas with a high proportion of suitable arable lands for contour farming are mainly found in the Da Hinggan Mountains and Changbai Mountains regions,with Ergun City(Inner Mongolia)having the highest pro-portion at 47.2%.Regions with higher suitability and proportion are concentrated in the Da Hinggan Mountains region,primarily cover-ing the Inner Mongolia and Heilongjiang.3)Regarding spatial clustering,both the area and proportion of suitable contour farming areas exhibit noticeable clustering effects,though not entirely consistent.4)Group analysis results designate 148 counties in BSR-NEC as highly suitable areas,predominantly located in the Changbai Mountains region,Liaodong Peninsula,Hulun Buir Plateau,and the north and south regions of the Da Hinggan Mountains.The zoning of suitable areas for contour farming in BSR-NEC informs the strategic de-velopment of policies and measures,allowing for the implementation of targeted policies in distinct areas suitable for contour farming.This provides a valuable reference for promoting contour farming technology more effectively and efficiently.re effectively and effi-ciently. 展开更多
关键词 contour farming spatial heterogeneity zoning policy spatial autocorrelation Black Soil Region of Northeast China(BSR-NEC)
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Brackish Shrimp Farming in Northeastern Brazil: The Environmental and Socio-Economic Impacts and Sustainability 被引量:1
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作者 Tadeu Dote Sá Rommel Rocha de Sousa +2 位作者 ítalo Régis Castelo Branco Rocha Gutemberg Costa de Lima Francisco Hiran Farias Costa 《Natural Resources》 2013年第8期538-550,共13页
Despite the economic importance of farmed shrimp, a number of technical, environmental, economic and social problems have been widely reported in the international literature. This paper focuses on the environmental a... Despite the economic importance of farmed shrimp, a number of technical, environmental, economic and social problems have been widely reported in the international literature. This paper focuses on the environmental and socio-economic impacts of semi-intensive and intensive shrimp farming in the coastal region of Northeastern Brazil and the identification of options for sustainable production. In this Region, the total area dedicated to shrimp farming is approximately 18,500 ha, of which 5750 ha are located in Ceará State. The estuary of Jaguaribe river has the largest number of shrimp farms in the state of Ceará. Currently, the industry has 64 participating farms with a total area dedicated to shrimp farming of 2411.3 ha. In 2011, the total production was 13,110 tons of shrimp with an average yield of 6330 kg ha1.year-1 in a pond area of 2071.2 ha. This industry employs 2350 people that represent 23.2% of jobs generated in the two municipalities where the Jaguaribe river estuary is inserted. Compared with other countries, Brazil has reduced its exports due to high cost inputs for shrimp farming. However, the Brazilian shrimp industry has benefited from high domestic prices, despite the decreases in international price of shrimp. In 2011, the prices for size category ranged between U$ 4.67 - 6.04 for 80/100 (count of head-on shrimp), U$ 4.95 - 6.60 for 70/80 and U$ 5. 展开更多
关键词 SHRIMP farm MANGROVES IMPACTS Environmental PENAEUS vannamei
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A comparison between different ecological de-farming modes in the loess hilly-gully region in China 被引量:3
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作者 XUYong GUOTengyun YANGGuoan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期53-60,共8页
The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been rega... The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been regarded as a powerful measure for the ecological restoration in the Loess Plateau and the upper reaches of the Yangtze River. "Relieving and de-farming" (RD) and "rebuilding terrace and de-farming" (RTD) are two more mature ones among various de-farming modes. Taking the loess hilly-gully region as a case, this paper summarized the basic characteristics of RD and RTD modes, calculated the sizes of de-farming slope farmland, rebuilt terraces, enlarged garden plots and restored vegetation, and compared the differences of two modes in terms of de-farming area, ecological reestablishment index, investment demand amount and benefits. The results showed that RTD mode has many advantages, including suitable investment, sufficient grain supply and great benefits, and will be the best ecological reestablishment mode in the loess hilly-gully region, and RD mode which is being carried out in this region should be replaced by RTD mode as soon as possible. 展开更多
关键词 ecological de-farming mode COMPARISON the loess hilly-gully region
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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China 被引量:2
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作者 JIANG Weiguo LI Jing +2 位作者 LI Jiahong CHEN Yunhao WU Yongfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期329-336,共8页
This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then di... This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows: (1) The eco-environment background condition becomes worse from southeast to northwest in the fanning-pastoral region of northern China. (2) The eco-environment background condition deteriorates from 1989 to 1999. (3) In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai orovince, eco-environmental deterioration is very serious. 展开更多
关键词 fanning-pastoral region eco-ENVIRONMENT spatial pattern northern China
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Feeding ecology of the mangrove oyster, <i>Crassostrea gasar</i>(Dautzenberg, 1891) in traditional farming at the coastal zone of Benin, West Africa
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作者 Alphonse Adite Stanislas P. Sonon Ghelus L. Gbedjissi 《Natural Science》 2013年第12期1238-1248,共11页
Wild collection management and farming of the mangrove oyster (Crassostrea gasar) occurring widely at the Benin (West Africa) coastal zone require knowledge on the feeding ecology to explore energy sources and nutriti... Wild collection management and farming of the mangrove oyster (Crassostrea gasar) occurring widely at the Benin (West Africa) coastal zone require knowledge on the feeding ecology to explore energy sources and nutritional needs. Six hundred thirty (630) individuals of C. gasar have been sampled in the rearing site at the Benin coastal lagoon to investigate on the trophic ecology of this cultivated bivalve. The diet analysis revealed that C. gasar is a filter-feeder foraging mainly on phytoplankton (72.70%) and substrate particles (22.95%). This trophic specialization results from anatomical structure, mainly the presence of gills which facilitate the filtering of number of plankton taxa. Dominant phytoplanktons ingested comprised of Diatomophycea (33.52%), Chlorophycae (17.19%), Scenedesmacae (13.80%), Dictyosphaeriacae (3.79%), and Pleurococcacae (2.75%). Eight genuses of phytoplankton, Polycystis, Coelosphaerium, Protococcus, Botryoccocus, Crucigenia, Melosira, Cyclotella, and Gyrosigma dominated the diet of C. gasar with aggreated volumetric proportions reaching 69.06% of the diet. Higher occurrences were recorded mainly for Melosira occurring in 263 (41.75%) stomachs, substrate particles in 211 (33.49%), and Polycystis in 151 (23.97%). C. gasar exhibited a high niche breadths varying from 4.54 to 5.78, suggesting that this bivalve consumed a high variety of food items, thus exhibiting a degree of trophic plasticity. Diet overlaps (?jk) among different size classes were high and varied from 0.71 to 0.98, indicating an ontogenetic diet shift pattern in C. gasar. Probably, to adapt to the benthic-muddy environment and to increase survival, C. gasar has evolved a specialized feeding mechanism and strategy to retrieve only needed nutrients for growth and to reject awful and nondigestible foods. Also, at the oyster rearing grounds, there is an evidence of shift in the food web structure leading to an increase of the biological productivity at the coastal zone. The output from this study is a valuable documentation for the sustainable development of oyster aquaculture, wild stock management and conservation. However, further scientific knowledge on nutritional needs, phytoplankton toxicity and habitat degradation, and improvement of farming techniques are required for an integrated oyster management. 展开更多
关键词 Conservation CRASSOSTREA Diet OVERLAPS farming Filter-Feeder Food Web FORAGING Strategy Phytoplankton
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Research on Influence Factors of Pig Farmers' Ecological Farming Behavior: Based on the TPB and SEM
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作者 Chengying HAN Zhenhong QI +1 位作者 Dongmin ZHANG Xinrui LI 《Asian Agricultural Research》 2016年第2期19-27,共9页
China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In ... China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In this process,farmers' behavior will play a key role. On the basis of summarizing development connotation and characteristics of ecological agriculture,using survey data of 323 pig farmers in 6 provinces,based on the Theory of Planned Behavior( TPB) it introduced individual characteristics and external environment constraint variables,and made an empirical analysis on factors influencing intention and behavior of pig farmers' ecological farming using the Structural Equation Model( SEM). Results indicate:( i) ecological farming intention of pig farmers has the largest direct effect on their ecological farming behavior;( ii)ecological farming cognition of pig farmers has significant positive effect on their ecological farming behavior;( iii) external environment has the largest indirect effect on their ecological farming behavior,followed by the overall effect,and external environment has significant positive effect on ecological farming attitude and cognition of pig farmers;( iv) individual characteristics( educational level and income level) of pig farmers influence ecological farming behavior of pig farmers through their ecological farming attitude and intention,but the degree of influence is limited. 展开更多
关键词 ecological farming BEHAVIOR Influence factors PIG farmERS Theory of PLANNED Behavior(TPB) Structural Equation Model(SEM)
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Effect of Combined Application of Organic Farming Aid (OFA) and Inorganic Fertilizers on the Growth and Yield of Maize and Soil Microbial Properties in the Guinea Savannah Agro-Ecological Zone of Ghana
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作者 O. A. Amoako J. Adjebeng-Danquah +8 位作者 R. Y. Agyare E. K. Akley H. Abeka Julius Yirzagla T. K. Tengey P. Teinor R. Alhassan A. A. Ibrahim C. Naapoal 《American Journal of Plant Sciences》 2023年第10期1180-1206,共27页
The aim of the study was to evaluate the effect of different rates of organic farming aid (OFA) and inorganic fertilizer on the productivity of maize, chemical and microbial properties of soil for higher economic valu... The aim of the study was to evaluate the effect of different rates of organic farming aid (OFA) and inorganic fertilizer on the productivity of maize, chemical and microbial properties of soil for higher economic value. Field experiments were conducted during the 2020 and 2021 cropping seasons at the research fields of CSIR-Savanna Agricultural Research Institute located at Nyankpala in the Guinea savannah agroecology of Ghana. The study consisted of five treatment combinations: full rate of OFA, full rate of NPK, 1/2 OFA + 1/2 NPK, full OFA + 1/2 NPK and a control (no OFA and no NPK) which were arranged in a randomized complete block design with four replications. Analysis of variance indicated significant (P 0.05) treatment and year interaction effect for all the growth parameters except for plant height, leaf area and leaf area index. Apart from hundred seed weight, treatment and year interaction effect for all the yield and yield components was significant (P 0.05). Application of full rate of NPK (90:60:60) resulted in the highest grain yield of 4960 kg·ha<sup>-1</sup>, however it was statistically similar to those obtained by the combined application of full rate of OFA (250 ml·ha<sup>-1</sup>) + 1/2 NPK and 1/2 OFA + 1/2 NPK with grain yield of 4856 kg·ha<sup>-1</sup> and 4639 kg·ha<sup>-1</sup> respectively. There was also a yield advantage of 197. 5%, 191.3%, 178.3 and 79.1% over the control for full NPK rate, full OFA rate + 1/2 NPK rate, 1/2 OFA rate + 1/2 NPK and full OFA rate respectively. Application of full OFA rate + 1/2 NPK enhanced soil basal respiration (evolved CO<sub>2</sub>) and mineralizable C, implying that, combination of full OFA rate and NPK fertilizer would be necessary to boost soil microbial activity and soil labile nutrient pool (labile C pool). This suggests that combined use of full OFA rate + 1/2 NPK fertilizer can be a better strategic tool for improving soil quality. The highest benefit cost ratios (BCR) of 2.58 and 3.77 were obtained following the application of full OFA rate + 1/2 NPK and 1/2 OFA rate + 1/2 NPK respectively. Hence, it could be concluded that complementary use of OFA and NPK is more profitable than using single inputs (either OFA or NPK). Thus, in promoting technology packages to farmers, development practitioners must carefully consider the complementary of inputs that are cost-effective but economically rewarding. 展开更多
关键词 Organic farming Aid Labile C Pool Wood Vinegar Combined Application
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The Influence of Land Use and Fish Farming on the Contents of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup>and Na<sup>+</sup>in Pond and Reservoir Ecosystems in an Agricultural Small Watershed, China
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作者 Jiaogen Zhou Caiyun Zhang 《Journal of Environmental Protection》 2021年第12期1174-1184,共11页
It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</... It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup>) in small water bodies of pond and reservoir ecosystems at the watershed scale. In this study, the concentrations of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup> in water bodies were measured for 103 ponds and reservoirs used as fish farming or surrounded by different agricultural land use types in the subtropical hilly watershed of Jinjing (105 km<sup>2</sup>), China. The two important environmental factors of fishing farming and agricultural land use influenced the spatial variation the contents of alkali metals. The ponds and reservoirs in residential area had significantly higher concentrations of Ca<sup>2+</sup> and Na<sup>+</sup> than those with other land use types, reflecting the influence of domestic wastewater. Compared with those of natural ponds with non-fish farming, no significant increase of alkali metal contents occurred in fish farming ponds, due to the regular cleaning of ponds by farmers. However, the effect of fish culture on alkali metal contents was still supported indirectly by the fact that the alkali metal contents significantly correlated with nitrate contents in fish farming ponds and but high related with that of DIP in natural ponds. The suitability assessment for irrigation on the pond water indicated that almost all of ponds were suitable for irrigation except some ponds surrounded by residential area and tea plantation. Generally, our results demonstrated that fish farming and agricultural land use affected the contents of alkali metals in ponds and reservoirs. The agricultural water irrigation would be with caution from the ponds with tea plantation and residential area in the subtropical hilly watershed. 展开更多
关键词 Land Use Alkali Metals Fish farming Agricultural Small Watershed Pond and Reservoir
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An Analysis of Farming in the Rural Economic Development of West Virginia
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作者 Saima Bashir Janaranjana Herath Tesfa Gebremedhin 《Journal of Agricultural Science and Technology(B)》 2012年第7期848-855,共8页
Farming is still an important sector in rural economic development of West Virginia where 44% of the population lives in rural areas and 24% of the land is used for farming. While income earnings, education and employ... Farming is still an important sector in rural economic development of West Virginia where 44% of the population lives in rural areas and 24% of the land is used for farming. While income earnings, education and employment rates are low in rural areas, poverty rates and unemployment are high compared to the urban areas. Thus, in the context of rural development farming is a potential major economic sector where 42% of the people's primary occupation is reported as farming. The objective of this study is to identify and estimate the potential impacts of farm employment in rural economic growth of West Virginia. Data from U.S. Bureau of Labor Statistics and U.S Census Bureau for the period of 1993 to 2008 are used for the empirical analysis. A model derived from the three simultaneous equations of Duncan is used for analysis. Three-Stage Least Squares (3SLS) method using the statistical package of STATA is used for estimation. The results concerning simultaneous relationships with population density growth, per capita income growth, and farm employment growth reveal significant importance of farming in rural economic development of West Virginia. Furthermore, the results indicate the positive impacts of population density, number of people with farming as principal occupation, and crop production on rural farming sector. 展开更多
关键词 farming rural economic development simultaneous equation 3SLS ANALYSIS West Virginia.
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German Eco-FarmingTakes Root
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《China Population Today》 2000年第4期20-20,共1页
关键词 eco German eco-farmingTakes Root
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Planning Method of Eco-environment Restoration Based on Enlarging Terrace and De-farming in Loess Hilly Region——A Case Study of Yangou Catchment
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作者 Lijuan DANG Yong XU 《Asian Agricultural Research》 2013年第8期62-67,共6页
After expatiating the guiding ideology,contents,standards and principles of eco-environment restoration based on enlarging terrace and de-farming,this paper discussed the planning method and technical flow of enlargin... After expatiating the guiding ideology,contents,standards and principles of eco-environment restoration based on enlarging terrace and de-farming,this paper discussed the planning method and technical flow of enlarging terrace and garden plot in a small catchment of loess hilly region by means of GIS spatial analysis technology,and then the planning method was applied in Yangou catchment.The result showed that it is practicabl,and the areas of newly-built terrace and garden plot in Yangou catchment are at least 295.06 and 4.61 hm2,so that the areas of basic farmland and garden plot reach 359.23 and 622.69 hm2.After the land use structure is regulated,the forest coverage is 48.87%,and the permanent vegetation coverage is about 75% in Yangou catchment,while sediment reduction benefit is above 80% in slope land.In agricultural development,Yangou catchment can yield 1 645.13 tons of food supplies,above 9 340 tons of apples,and can feed 7 500 sheep every year. 展开更多
关键词 ENLARGING TERRACE and de-farming PLANNING method o
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Subsistence Farming Towards Sustainable Economic Agriculture of Small Farmers in the Developing Countries
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作者 Fawzy Z F Shaymaa I.Shedeed 《NASS Journal of Agricultural Sciences》 2020年第1期1-3,共3页
Subsistence farming,a form of cultivation in which almost all crops or livestock are used to maintain farms and the farm family,leaving little,surplus for sale and trade.Pre-industrial farming peoples all over the cou... Subsistence farming,a form of cultivation in which almost all crops or livestock are used to maintain farms and the farm family,leaving little,surplus for sale and trade.Pre-industrial farming peoples all over the countries of the worldwide apply subsistence agriculture system and take advantage of the possibilities available to them from land and water resources in all locations of agriculture sites.The agricultural production has become more specialized and developed in the subsistence farming system,and farmers have produced abundant production from many horticulture crops that are traded among them and achieve their selfsufficiency from those crops. 展开更多
关键词 Subsistence farming Agriculture sector Developing countries
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