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A Multi-Site Case Study on Social Vulnerability to Climate Change of Select Rain-fed Farming Communities in the Philippines
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作者 Melanie P. Tolentino 《Sociology Study》 2013年第9期665-677,共13页
This study examines social vulnerability by exploring the socio-economic factors, infrastructures, and social networks that can determine how prone and how prepared the rain-fed farming communities are to the adverse ... This study examines social vulnerability by exploring the socio-economic factors, infrastructures, and social networks that can determine how prone and how prepared the rain-fed farming communities are to the adverse impacts of climate change. Increased variability in climatic conditions due to climate change seriously affects the productivity of rain-fed farms. The rain-fed farming communities in the Philippines are located in poor and environmentally fragile rural areas. Their vulnerability is greatly affected by restricted entitlement and access to social and economic capitals. This study is framed on qualitative approach to provide a rich and in-depth understanding on the elements of vulnerability based on the capacities and the practical affairs of life in rain-fed communities. The three subject communities from two agricultural provinces are examined to understand how the context and interactions of people can explicate sociological themes on the social dimension of climate change. The usefulness of multi-site study in probing the unique ways of how people understand and respond to certain environmental issue is part of reflections about the methodology. 展开更多
关键词 Social vulnerability climate change climatic variability rain-fed farming
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Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in China 被引量:19
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作者 DENG Xiangzheng, LIU Jiyuan, ZHUANG Dafang, ZHAN Jinyan, ZHAO Tao(Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第4期397-404,共8页
This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorph... This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions. 展开更多
关键词 land use driving force interlock area of farming and pasturing China
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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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Stand Structure, Diversity and Regeneration Status of Woody Species in Open and Exclosed Dry Woodland Sites around <i>Molapo</i>Farming Areas of the Okavango Delta, Northeastern Botswana 被引量:2
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作者 John Neelo Demel Teketay +1 位作者 Keotshephile Kashe Wellington Masamba 《Open Journal of Forestry》 2015年第4期313-328,共16页
Stand structure, diversity and regeneration status of woody species were investigated in open and exclosed dry woodland sites in Island Safari, Shorobe and Xobe, northeastern Botswana. A total of 105, 111 and 130 quad... Stand structure, diversity and regeneration status of woody species were investigated in open and exclosed dry woodland sites in Island Safari, Shorobe and Xobe, northeastern Botswana. A total of 105, 111 and 130 quadrats, measuring 20 × 20 m each, were laid down along parallel line transects in the three sites, respectively, to collect data. A total of 47 species, representing 16 families and 24 genera, were recorded in the study sites. Of these, 33 species representing 13 families and 20 genera, 41 species representing 15 families and 23 genera and 27 species representing 10 families and 14 genera were encountered in Island Safari, Shorobe and Xobe, respectively. The most diverse family was Fabaceae followed by Combretaceae and Tiliaceae at all the three sites. The most diverse genus was Acacia, followed by Combretum and Grewia. The diversity of woody species in the study sites were 2.18, 2.15 and 1.5 in Shorobe, Island Safari and Xobe, respectively, while their corresponding evenness values were 0.6, 0.6 and 0.5, respectively. The mean densities of the woody species encountered in Island Safari, Shorobe and Xobe were 2629, 4271 and 2745 individuals ha&#451, respectively. The five densest species were Colophospermum mopane, Dichrostachys cinerea, Acacia tortilis, Philenoptera violacea and Terminalia prunioides in Island Safari, C. mopane, A. tortilis, A. erioloba, P. violacea and D. cinerea in Shorobe and Acacia mellifera, A. tortilis, P. nelsii, A. luederitzii and A. erubescens in Xobe. The highest important value index values were exhibited by C. mopane, D. cinerea, A. tortilis, P. violacea and T. prunioides in Island Safari, C. mopane, A. erioloba, A. tortilis, P. violacea and C. imberbe in Shorobe, and A. mellifera, A. tortilis, P. nelsii and A. luederitzii in Xobe. The alarming result was the fact that 71%, 80% and 85% of the woody species recorded in Island Safari, Shorobe and Xobe, respectively, exhibited hampered regeneration and, thus, unhealthy population structures. Therefore, there is an urgent need to address the observed unhealthy population structures of the woody species through investigation of the major causes of their hampered regeneration, and also designing measures that will facilitate natural and artificial regeneration of these species at the three study sites. 展开更多
关键词 Anthropogenic Disturbance area EXCLOSURE Deforestation Density DIVERSITY Flood Recession (Molapo) farming Important Value Index Population Structure REGENERATION
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Protected Areas, Subsistence Farming Systems and Nature Conservation
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作者 Luis Tiberio Filipa Manso Ana Marta-Costa Carlos Fonseca Aurora Monzon 《Journal of Agricultural Science and Technology(A)》 2012年第3期402-411,共10页
The preservation of the traditional subsistence farming systems and the conservation of natural values (habitats, fauna and flora), in articulation with local development, was the key issues in this paper. The farme... The preservation of the traditional subsistence farming systems and the conservation of natural values (habitats, fauna and flora), in articulation with local development, was the key issues in this paper. The farmers have been able to manage the systems so as to cope with adverse conditions, but their future is quite uncertain. The methodology included: (1) field observation visits and cartographic information analysis of land use; (2) structured interviews with animal production and agro-forestry specialists; and (3) meetings with the participation of stakeholders. The paper concludes that depopulation is responsible for the increasing decline of agriculture and livestock. The decrease in agricultural activity in general and the consequent practices and traditional systems of agriculture causes changes in the landscape and has negative effects on nature conservation and biodiversity. Thus, we believe that the preservation and development of traditional economic activities linked to agriculture, agro-forestry and food processing are essential to maintain the typical landscape and to preserve natural values of Montemuro Site. The paper shows that in mountain areas, particularly those classified as nature network sites, farming, economic development and nature conservation are not antagonistic objectives. 展开更多
关键词 farming systems protected areas nature conservation BIODIVERSITY local development.
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On the Rice Farming in the Shu Area During the Can Cong Period
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作者 Xin Yan Zhang Hongying 《Contemporary Social Sciences》 2023年第1期131-143,共13页
The Bashu area was one of the most civilized agricultural areas in ancient China.Since the late Eastern Han Dynasty,it has been reputed as the“Land of Abundance”due to its abundant resources.Archaeological data show... The Bashu area was one of the most civilized agricultural areas in ancient China.Since the late Eastern Han Dynasty,it has been reputed as the“Land of Abundance”due to its abundant resources.Archaeological data show that the Shu area cultivated millet as early as the prehistoric period.The legend goes that Can Cong was the first ruler of the Shu area during the pre-Qin period,indicating that agricultural production at that time had made great progress compared with the prehistoric period.During this period,the agricultural pattern of the Shu area experienced profound changes,from dryland millet farming originating from the Western Sichuan Plateau to rice farming that is more suitable for Sichuan Basin,especially for the Chengdu Plain,where there are abundant rainfalls and high temperatures.Since then,rice farming has become a long-established farming tradition in the Shu area.The agricultural production tools and grain crop seeds unearthed from the Baodun site,where the archaeological remains of Can Cong Culture were discovered,show the prosperity of early agriculture in the Shu area.During the Baodun Culture period,the accelerated economic and social development in the Shu area promoted complicated and hierarchical changes in the social organization structure of settlements,which gradually evolved into early states. 展开更多
关键词 Can Cong Shu area Baodun Culture rice farming
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Risk Assessment of Tropical Cyclones to Wind Farm Operation in Northern Costal Areas of Jiangsu Province
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作者 Huanling Feng 《Meteorological and Environmental Research》 CAS 2013年第8期17-20,共4页
[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basi... [Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basic weather stations as well as wind data during 2005 -2007 de- termined by six gradient wind measurement towers in northern costal areas of Jiangsu Province, the spatial and temporal distribution of tropical cy- clones influencing northern coastal areas of Jiangsu Province were discussed firstly, and then the possible effects of tropical cyclones on wind farms in the northern costal areas were assessed, finally some suggestions about type selection and parameter design of wind turbines were proposed. Restult Annual average number of tropical cyclones influencing northern coastal areas of Jiangsu Province was 1.7, and the first two kinds of tropical cyclones were dominant in quantity, accounting for about 73% for total quantity. The quantity of tropical cyclones bringing substantial economic benefits to wind farms accounted for 87.7% of total quantity, with annual average quantity of 1.5. Maximum wind speed appearing every 50 years did not exceed 37.5 m/s, in accord with the national Grade-Ill standard for safe operation of wind turbines. 2.1% -3.8% of turbulence intensity ei- genvalues at a height of 70 m exceeded the maximum anti-turbulence intensity designed by IEC (0.16), and it is suggested that anti-turbulence in- tensity parameter of wind turbines in northem costal areas of East China should be changed to 0.31 -0.41. [ Conclusion] The research could provide scientific references for design and choice of wind turbines as well as operation and management of wind farms in the study region in future. 展开更多
关键词 Tropical cyclone Wind farm Coastal areas ASSESSMENT China
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Quantity Calculation of the Land Unsuitable for Farming: A Case Study of Anze County in Shanxi Province
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作者 Kangkang CHANG Longyi XUE Tao XUE 《Asian Agricultural Research》 2016年第5期67-70,共4页
Adhering to the " red line" of 1800 million mu of arable land is China's arable land protection guideline and policy,and the " red line" places emphasis on both quantity and quality of arable l... Adhering to the " red line" of 1800 million mu of arable land is China's arable land protection guideline and policy,and the " red line" places emphasis on both quantity and quality of arable land. Taking Shanxi's Anze County as an example,based on ecological safety and natural suitability criteria,we select 10 evaluation indicators to evaluate the farming suitability of existing land in the county. Results show that Anze County needs to reuse 48. 7% of the existing arable land for ecological purpose in order to ensure ecological safety. It still retains 51. 3%of existing arable land after abandoning tillage,which can ensure 0. 15 ha of arable land per capita,743. 12 kg of grain per capita and 170%of food self-sufficiency rate,thereby fully ensuring food safety. The farming suitability evaluation of land resources should not only consider the natural suitability of land,but also consider ecological safety. Faced with the new situation of arable land protection,it is necessary to explore new farmland protection theories and indicator systems based on actual conditions,to meet the requirements of sustainable development of population,resources and ecology. 展开更多
关键词 ECOLOGICAL COUNTY farming SUITABILITY Minimum per capita area of ARABLE LAND
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Assessment of Coffea Shade Value through Comparison of Mountainous Area with Farm Land Coverage,in Arsi Gololcha District,Oromia,Ethiopia
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作者 Alemayehu Diriba Roba 《Journal of Botanical Research》 2021年第4期29-36,共8页
Coffea cultivation with shade tree is used for improving soil health,increasing coffea production,sustaining agro ecology.The study was attended in two kebele,on 36 farmers’fields,at Gololcha district of East Arsi zo... Coffea cultivation with shade tree is used for improving soil health,increasing coffea production,sustaining agro ecology.The study was attended in two kebele,on 36 farmers’fields,at Gololcha district of East Arsi zone.The study was intended to assess the influence of coffea shade trees on farm lands versus mountainous area.Household interviews were used to get imperative separately,i.e.from old farmers,middle age farmers and young farmers.Significant difference value was observed between farm land and mountainous area coverage.Based on this respondents’idea,before 25-30 years;the‘condition of tree coverage at mountainous’area in Arsi Gololcha district was‘medium condition’but not normal that means as deforestation of mountainous area have been starting before 30 years’time;while the condition of tree coverage at farmland area also has been starting before 30 years’time.The third respondents’idea was interpreted with the real situation of the district,that it gave us a constructive inspiration on the role of coffea shade tree to enable the farm land to be taken as regular natural forest.The existing coffea shade trees are Cordia africana followed by Erythrina abyssinica and Acacia senegal.Farmers accounted 95%of coffea shade users and 4.6%without shade users.The respondents said that even if the rainfall intensity is increasing at farmland rather than mountainous area occasionally due to shade tree effect.On the contrary side,mountainous area exposed to deforestation since the farmers have been shifting to hilly side for their livelihood dependency. 展开更多
关键词 farm lands versus mountainous areas Ecological value of Coffea shade trees
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Effect of Irrigation on Groundwater Dynamic Change in the Typical Irrigated Area of Qinghai Province 被引量:2
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作者 周鸿文 吕文星 +2 位作者 唐红波 王永峰 申国峰 《Agricultural Science & Technology》 CAS 2016年第7期1718-1722,共5页
Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater o... Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater observation wells were constructed in experimental plot of the Daxia irrigated area to carry out the experiment of the effect of irrigation on groundwater dynamic change in this research. The results showed that the groundwater stage dynarnic change rule of spring and seedling irri- gation stage in the typical plot was fit to the hydrological geology condition of grade- I terrace of Huangshui river valley. On the whole, lateral canal water direction formed a line effect. The No. 1 and No. 2 observation well were the closest to the lateral canal, which received more supplies, and the water level was the highest; the No, 3 observation well took the second place; The No. 4 and No. 5 observation well accepted least supplies, and the water level was the lowest. The rangeability of water table of spring irrigation period was significantly higher than that of seedling irrigation period, this is mainly due to the difference value of intake water volume and drainage water volume of spring irrigation phase was significantly higher than the seedling irrigation phase. 展开更多
关键词 farm irrigation Water table Dynamiq Change Typical irrigated area basin in Qinghai Province
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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS 被引量:4
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作者 ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China +1 位作者 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期915-921,共7页
By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of ... By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure. 展开更多
关键词 slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir area
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Heavy Metal Contaminated Food Crops Irrigated with Wastewater in Peri Urban Areas, Zambia 被引量:8
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作者 Evaristo Mwaba Kapungwe 《Open Journal of Metal》 2013年第2期77-88,共12页
Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and... Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia. 展开更多
关键词 HEAVY Metal Contamination WASTEWATER Soils Food CROPS IRRIGATION farming Peri Urban areas Zambia
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Potato yield gaps across the rainfed Yin-mountain Hilly Area of China 被引量:2
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作者 JIA Li-guo CHEN Yang +4 位作者 QIN Yong-lin LIANG Rui-fang CUl Shi-xin MA Zhong FAN Ming-shou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第11期2418-2425,共8页
Yin-mountain Hilly Area is one of the ideal regions for potato (Solanum tuberosum) production in China. However, potato yield is severely limited as a result of rain-fed crop mode due to water deficiency, as well as... Yin-mountain Hilly Area is one of the ideal regions for potato (Solanum tuberosum) production in China. However, potato yield is severely limited as a result of rain-fed crop mode due to water deficiency, as well as an inadequate farming practices. In this study, yield gaps were determined by using attainable yield (Ya) as a benchmark under optimized management practices, i.e., micro-ridge and side planting with plastic-mulching (MS), and flat planting with plastic-mulching (PM). The yields under MS and PM modes are defined as Yal and Ya2, respectively. Under the same field with MS and PM modes but different densities and fertilizer usages and so on, it was defined as simulated farmers' practices. The yield of simulated farmers' practices (Yfl) reached 57.3 and 69.6% of Yal and Ya2, respectively, while the average yield of 298 randomly surveyed farmers (Yf2) reached only 37.0 and 47.8% of Yal and Ya2 for rain-fed potato, respectively. The gaps of water use efficiency exhibited similar pattern. Further analysis shows that improper measures in rainwater conservation and accumulation, and other management practices contributed to 18.5, 18.2, and 42.6% of yield gap between Yal and Yf2. Improper nutrition management, including overuse of nitrogen and the deficiency of phosphorus andpotassium supplication, was one of the important reasons of yield gap. The results indicate the possibilities of increasing rain-fed potato yields by optimized water and fertilizermanagements in the Yin-mountain Hilly Area. 展开更多
关键词 rain-fed POTATO yield gap water management Yin-mountain Hilly area
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Impact of livelihood diversification of rural households on their ecological footprint in agro-pastoral areas of northern China 被引量:21
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作者 HAO Haiguang ZHANG Jiping +2 位作者 LI Xiubin ZHANG Huiyuan ZHANG Qiang 《Journal of Arid Land》 SCIE CSCD 2015年第5期653-664,共12页
Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data... Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance (ANOVA) and correlation analysis methods. In 2011, the total ecological footprint of consumption (EFC) was 0.665 g hm2, and the total ecological footprint of production (EFP) was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption (EFAC) accounted for a large proportion of the EFC, and the ecological footprint of grassland production (EFGP) occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption (EFGC) and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households (FTFHs) had the highest EFP, ecological footprint of arable land production (EFAP), EFGP and EFGC, followed by the part-time farming households (PTFHs) and non-farming households (NFHs), which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future. 展开更多
关键词 ecological footprint livelihood diversification livestock rearing non-farming employment rural households agro-pastoral area
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Study on Sustainable Development in Vulnerable Eco-areas
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作者 Zhang Juntao & Li Jin School of Public Administration, Dongbei University of Finance and Economics, Dalian 116025, China 《Chinese Journal of Population,Resources and Environment》 2004年第3期14-19,共6页
The vulnerable eco-area is one of the important research targets in the field of sustainable development. It is the requirement of building a well-off society in an all-round way that we should study more on the vulne... The vulnerable eco-area is one of the important research targets in the field of sustainable development. It is the requirement of building a well-off society in an all-round way that we should study more on the vulnerable eco-areas, deal with the relationship between environmental protection and economic development, speed up the economic development in these areas and increase the living standard of the local people. This paper puts forward the countermeasures of environment---economy coordination, on the basis of the recognition of eco-environment features and social economic conditions in the vulnerable eco-areas of China, in view of the progress in sustainable development studies of the vulnerable ones, taking the transitional areas of farming and pasturing in northeast China as an example to study the regional environment vulnerability. 展开更多
关键词 vulnerable eco-area sustainable development transitional areas of farming and pasturing in northeast China
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Simulated Influence of Mountainous Wind Farms Operations on Local Climate
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作者 AI Ze HE Fei +2 位作者 CHEN Zheng-hong ZHONG Shui-xin SHEN Yan-bo 《Journal of Tropical Meteorology》 SCIE 2022年第1期109-120,共12页
Renewable energy sources,especially wind power,were believed to be able to slow down global warming;however,evidence in recent years shows that wind farms may also induce climate change.With the rapid development of w... Renewable energy sources,especially wind power,were believed to be able to slow down global warming;however,evidence in recent years shows that wind farms may also induce climate change.With the rapid development of wind power industry,the number of wind farms installed in mountains has gradually increased.Therefore,it is necessary to study the impact of wind farms in mountainous areas on local climate.The Suizhou and Dawu wind farms in northern Hubei Province were chosen for the present study on the impact of wind farm operations on the local climate in mountainous areas.The mesoscale meteorological numerical model Weather Research and Forecasting Model(WRF)and the Fitch model,together with turbulence correction factor,were used to simulate wind farm operations and study their effects on local climate.The results showed the characteristics of wind speed attenuation in mountainous wind farms:the amplitude and range of wind speed attenuation were stronger in the nighttime than in the daytime,and stronger in summer than in winter.The surface temperature increased and became more significant in summer.However,a cooling variation was observed above the surface warming center.The height of this center was higher in the daytime than it was in the nighttime.The latent heat flux in the wind farms decreased at night,accompanied by an increase in sensible heat flux.However,these changes were not significant.Some differences were observed between the impact of wind farms on the climate in the plains and the mountains.Such differences are more likely to be related to complex terrain conditions,climate conditions,and the density of wind turbines.The present study may provide support for the development and construction of wind farms in mountainous areas. 展开更多
关键词 mountainous area wind farm local climate energy field numerical simulation
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Analysis of the Criticizes for Zootechnics Development in a Mountain Area of Italy
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作者 Simona Rainis Sirio Rossano Secondo Cividino +1 位作者 Franco Sulli Elena Valent 《Journal of Life Sciences》 2013年第8期846-855,共10页
The paper considers the main causes of the difficulties of zootechnics in Friulian mountains (Italy), evaluating different approaches. From the methodological point of view, there were analyzed the different aspects... The paper considers the main causes of the difficulties of zootechnics in Friulian mountains (Italy), evaluating different approaches. From the methodological point of view, there were analyzed the different aspects that causes the present crisis in this territorial contest and that, contextually, at the same time, prevent its recovery. The procedural pathway followed these steps: analysis, synthesis, comparison, deduction and induction. The results showed that there are technical, social, environmental, political and infra-structural aspects that cause this stated economical emergency for the compartment. A "new rural paradigm", in particular, the multi-functionality of the farm seems to be the road to the progress of mountain regions. Unfortunately, there are no definitive universal answers, hut individual solutions that should be investigated and calibrated for specific local resources. 展开更多
关键词 Sustain rural development marginal and mountain areas livestock farming systems.
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滨海盐田土壤碳时空分布特征及碳收支 被引量:1
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作者 苟富刚 王光亚 蔡露明 《现代地质》 CAS CSCD 北大核心 2024年第2期497-508,共12页
滨海盐田存在土壤盐碱化、瘠薄与有机碳含量低等障碍问题,有关滨海盐田土壤碳方面的系统研究目前依然缺乏典型实例剖析。为了揭示滨海盐田以及用地类型发生转变后土壤的有机碳时空分布特征、影响因素及碳收支,选取江苏省连云港市徐圩新... 滨海盐田存在土壤盐碱化、瘠薄与有机碳含量低等障碍问题,有关滨海盐田土壤碳方面的系统研究目前依然缺乏典型实例剖析。为了揭示滨海盐田以及用地类型发生转变后土壤的有机碳时空分布特征、影响因素及碳收支,选取江苏省连云港市徐圩新区和青口盐场的土壤为研究对象,采取表层(0~20 cm,2004年和2019年两期数据)土壤及深层(150~200 cm,2004年一期数据)土壤样品,进行了土壤有机碳(SOC)、总碳(TC)及总氮(TN)的测试。结果表明,SOC储量呈增加趋势,碳汇区面积占比69.4%,碳源区占比30.6%,不同用地类型SOC含量与平均固碳速率差异较大。2004年表层SOC含量分布在低、中两个等级区间,2019年SOC含量在中等级分布频率最高。近15年盐田1区(用地类型保持不变)SOC含量增加了0.12%,盐田2区(耕地)SOC含量增加了0.42%,盐田3区(建设用地)SOC含量增加了0.13%。平均固碳速率最高值出现在耕地类型,数值达到了5.83×10^(4)kg·km^(-2)·a^(-1)。盐田1区土壤有机碳的分解主要通过微生物的异氧呼吸途径来实现,有机碳的有氧矿化主要通过真菌与细菌的有氧矿化来实现。滨海盐土具有高含量的SO_(4)^(2-)与Ca~(2+),有机碳的厌氧矿化主要通过SO_(4)^(2-)还原来实现,因此无机碳的增加速率较大,达到3.64 g·m^(-2)·a^(-1)。盐田1区两期数据SOC/TN平均值均为9.9,说明土壤环境稳定。盐田3区SOC/TN稍有下降,推测原因是土壤微生物量及酶活性提高导致SOC的矿化速率增加。在环境问题日益严重和土壤质量趋向恶化的情况下,本文的研究成果为滨海盐田及其土地利用类型转变后的土壤碳循环研究提供了新的基础依据。 展开更多
关键词 有机碳 无机碳 徐圩新区 青口盐场 碳循环
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Does labor off-farm employment inevitably lead to land rent out?Evidence from China
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作者 DENG Xin XU Ding-de +1 位作者 ZENG Miao QI Yan-bin 《Journal of Mountain Science》 SCIE CSCD 2019年第3期689-700,共12页
The focus of land economics is on how to decrease the misallocation of resources to achieve an optimal allocation of resources. Both the theories of new economics of labor migration(NELM) and the conclusions of empiri... The focus of land economics is on how to decrease the misallocation of resources to achieve an optimal allocation of resources. Both the theories of new economics of labor migration(NELM) and the conclusions of empirical studies reveal that land resources will inevitably be reallocated(e.g., rented out) if the resources of family labor are reallocated(e.g., off-farm employment). However, this study reveals that off-farm employment does not inevitably lead to land rent out. More precisely, this study uses survey data on 8031 peasant households from 27 provinces in China and explores the relationship between off-farm employment and land rent out by describing spatial features and through empirical analysis(e.g., IV-Probit model and IV-Tobit model). The results show the following: 1) There is an indirect relationship between off-farm employment and land rent out regarding spatial area aggregation, i.e., regions with a higher ratio of off-farm employment also have a lower area of land rent out. 2) Off-farm employment is significantly positively correlated with the behavior of land rent out, but its square is significantly negatively correlated with the behavior, i.e., there is an inverted U-shaped relationship between off-farm employment and the behavior of land rent out, with the turning point being 55.55% offfarm employment. 3) Off-farm employment is significantly positively correlated with the area of land rent out, but its square is significantly negatively correlated with the area, i.e., there is an inverted Ushaped relationship between off-farm employment and the area of land rent out, with the turning point being 56.22% off-farm employment. This study helps explain why China has a high ratio of off-farm employment but a lower rate of land rent out. 展开更多
关键词 RURAL LABOR Off-farm EMPLOYMENT Land RENT OUT RENT OUT area China
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Soil Acidity: Is It a Problem in Large Scale Commercial Farms in Zimbabwe?
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作者 T. P. Tauro F. Mapanda, G. Mtombeni A. Shumba D. K. C. Dhliwayo 《Journal of Agricultural Science and Technology》 2011年第2期168-174,共7页
A study was conducted to identify the causes of low crop yield on a large scale commercial farm in Zimbabwe. Soil and water samples were collected from fields (0-60 cm) and the dam used for irrigation, respectively.... A study was conducted to identify the causes of low crop yield on a large scale commercial farm in Zimbabwe. Soil and water samples were collected from fields (0-60 cm) and the dam used for irrigation, respectively. Soil samples were analysed for soil fertility characteristics while the water was analysed for irrigation quality. The soils on the farm were heavy, ranging from sand loams to sand clays and fertile (〉 40 mg kgl N and 〉 20 mg kg1 available P) indicating high fertilizer utilization. It was also noted that 50% of the fields on the farm had soil pH below 5.0 despite having high basic cation (Ca = 10-18 meq% and Mg = 4-7 meq%). A similar trend was observed down the soil profile (30-60 cm). The soil also had extremely high concentration of iron (〉 200 ppm), manganese (〉 400 ppm) and sulphate (〉 4000 ppm). These findings suggest that the extreme acidity under these soils is the outcome of the exposure of pyrite to moisture and air by tillage of the land. The water used for irrigation was established to be medium saline and alkaline (pH 〉 7.6). This pyrite induced acidity could not be neutralised by the water from the dam and the high exchangeable bases in the soil. Such problems can possibly be managed by growing tolerant crops. Soil testing on commercial farms is vital for identifying such problems in commercial farms in Zimbabwe. 展开更多
关键词 Soil acidity PYRITE commercial farming area soil testing.
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