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1.
In the northern highlands of Ethiopia degraded hillsides have been allocated to landless farmers for tree planting since the mid-1990s. The authors assessed the effect of hillside plantations on the livelihoods of landless farmers in the eastern part of the Tigray Region by using transect walks, focus group discussions, and pretested questionnaires. A matched-pairs design was used to compare crop yields, livestock holdings per household, and household incomes to test the differences before and eight years after the intervention. In addition, regression analysis was used to capture variables influencing hillside management. The findings revealed that the plantations significantly increased crop yields, livestock holdings, and the household incomes of all beneficiaries. In addition, tree planting on degraded hillsides had a positive impact on the livelihoods of formerly landless farmers. However, moisture stress and free-ranging livestock were crucial problems. The findings are highly relevant in a conservation context because many existing or planned hillside allocations to landless farmers are located on degraded steep slopes that are unsuitable for crop production. Thus, replicating the practice to other areas with similar environment and problems would be worthwhile, although the management should focus on careful planning to avoid conflicts of interest between beneficiaries and non-beneficiaries.  相似文献   

2.
Rice(Oryza sativa L.) is the most important staple crop of China, and its production is related to both natural condition and human activities. It is fundamental to comprehensively assess the influence of terrain conditions on rice production to ensure a steady increase in rice production. Although many studies have focused on the impact of one or several specific factors on crop production, few studies have investigated the direct influence of terrain conditions on rice production. Therefore, we selected Hunan Province, one of the major rice-producing areas in China, which exhibits complex terrain conditions, as our study area. Based on remote sensing data and statistical data, we applied spatial statistical analysis to explore the effects of terrain factors on rice production in terms of the following three aspects: the spatial patterns of paddy fields, the rice production process and the final yield. We found that 1) terrain has a significant impact on the spatial distribution of paddy fields at both the regional scale and the county scale; 2) terrain controls the distribution of temperature, sunlight and soil, and these three environmental factors consequently directly impact rice growth; 3) compared with the patterns of paddy fields and the rice production process, the influences of terrain factors on the rice yield are not as evident, with the exception of elevation; and 4) the spatial distribution of paddy fields mismatched that of production resources due to terrain factors. Our results strongly suggest that managers should scientifically guide farmers to choose suitable varieties and planting systems and allocate rice production resources in the northern plain regions to ensure food security.  相似文献   

3.
This article examines the role of coffee in the agriculture of southwest Ethiopian highlands, a context characterized by recent huge private coffee estate developments, coffee certification projects and smallholdings. The analysis shows that smallholder farmers prioritize staple crops, and allocate land and labor to coffee only once food production objectives have been reached. It also underscores the diversity of the local peasantry, often treated as a homogeneous group in development projects designed to boost farmers' income through coffee production. Based on this analysis, the article evaluates the effects of recent coffee-oriented development policies: state forest concessions for coffee investment, and two coffee certification projects (UTZ-Certified and Fair-Trade/Organic). Because they omit the differentiated farmers' strategies, these certification initiatives fail to improve local populations' livelihoods and accelerate incipient socioeconomic inequalities. Moreover, when applied to big private plantations, they participate in farmers' dispossession from critical forest resources essential to households' food self-sufficiency.  相似文献   

4.
Destruction of forests and the considerable burning of fossil fuels is directly causing the level of carbon dioxide and other greenhouse gases including methane, carbon monoxide, and nitrous oxide in the atmosphere to rise. Population growth in the US and the world indirectly contributes to this global warming. This has led the majority of scientists interested in weather and climate to predict that the planet's temperature will increase from 1.5 to 4.5 degrees Celsius by 2050. These forecasted climactic changes will most likely strongly affect crop production. Specifically these scientists expect the potential changes in temperature, moisture, carbon dioxide, and pests to decrease food production in North America. The degree of changes hinges on each crop and its environmental needs. If farmers begin using improved agricultural technology, the fall in crop yields can be somewhat counterbalanced. Even without global warming, however, agriculture in North America must embrace sensible ecological resource management practices such as conserving soil, water, energy, and biological resources. These sustainable agricultural practices would serve agriculture, farmers, the environment, and society. Agriculturalists, farmers, and society are already interested in sustainable agriculture. Still scientists must conduct more research on the multiple effects of potential global climate change on many different crops under various environmental conditions and on new technologies that farmers might use in agricultural production. We must cut down our consumption of fossil fuel, reduce deforestation, erase poverty, and protect our soil, water, and biological resources. The most important action we need to take, however, is to check population growth.  相似文献   

5.
As the consequence of climate change, water that is received in Australian Murray-Darling Basin wetlands is declining and agricultural water demands are increasing. In order to keep the water use balance between environment protection including wetland protection and irrigation water use, the Australian government adopted a series of reforms in Murray-Darling Basin to address the environmental water shortage problem and encourage irrigators to use water more efficiently and plant high economic value crop. The water trading and cap are two major reforms in this process.In order to match up the environmental water demand such as wetland water use, based on the seasonal rainfall, dam level and environmental water demand, the cap system seasonally allocate how much water the irrigators can access as per water licenses. As the cap dramatically reduced the water access for irrigators, the water trading is aiming to use limited agricultural water more efficiently. The water trading scheme separate the water use right from the land property right and allow Australian farmers to trade their water licenses in the market. Water trading encouraged farmers who plant low value crops such as wheat and canola transfer their water entitles to farmers who plant high value crops such as grape. In the drought seasons, The Australian government can purchase the water licenses from irrigators to increase the environmental flows.This Australian water management system represents the most complicated and effective environmental and agricultural water use management in this world. There are possible many lessons that will help China to better manage the water use for wetland protection and farming practices.  相似文献   

6.
湖南省地形因素对水稻生产的影响   总被引:3,自引:0,他引:3  
王琛智  张朝  张静  陶福禄  陈一  丁浒 《地理学报》2018,73(9):1792-1808
作为一种人工生态系统,水稻的生产受自然条件和人为管理的共同影响。其中,地形因素不仅决定了水稻生长必须的光热等资源的再分配,而且还影响人类的农业管理活动。以中国水稻主产区中地形较为复杂的湖南省为研究对象,基于多种数据,从生态学的“格局—过程”思想出发,讨论了地形因素对水田分布、水稻生长过程及水稻产量的影响。研究发现,地形因素对水田分布的空间格局影响最为明显,对水稻生长过程影响次之,而对水稻产量影响较弱。在各地形因素中,高程对于水稻生产的影响最为突出。研究结果还反映出地形因素造成了湖南省水田分布和热量分配在北部平原地区的不匹配,政府部门应根据区域特征,因地制宜采取措施,提高该地区水稻生产效益。  相似文献   

7.
The worldwide increase in the use of biomass as a Renewable Energy Source raises the issue of introducing crops dedicated to energy production into rural landscapes. The purpose of this paper is to set-up a GIS based multi-criteria approach to assess a range of possibilities for perennial energy crops conversion. The presented method was implemented at the regional level in the Yorkshire and the Humber Region in Northern UK. The first phase of the study aims to set-up a land capability model for the specific purpose of assessing the potential of different typologies of perennial energy crops, on the basis of specific pedo-climatic and topographic factors. The model output illustrates a range of potentials for energy crop conversion that can be explored in the given landscape. In the second phase a uncertainty analysis of the land capability model was performed through a simulation approach in order to interpret the influence of assumptions and uncertainty on input data and model parameters. The last phase of the study allows allocating the energy crop conversion area according to specific environmental constraints, nature protection targets, food production priorities and land capability values. The land allocation output gives a rather restrictive energy crop penetration scenario, where more than half of the conversion area is allocated to cropping systems with low land degradation potential. This scenario represents a preliminary regional analysis of the energy crop potential in terms of theoretically available conversion areas. The final results also show that the areas with highest environmental risks correspond to the areas with both the lowest suitability for energy crop cultivation and the highest model uncertainty.  相似文献   

8.
石羊河下游农户的土地利用行为及效率   总被引:1,自引:0,他引:1  
张丽琼  赵雪雁  郭芳  李文美 《中国沙漠》2015,35(6):1715-1722
农户的土地利用行为不仅决定着土地资源能否可持续利用,更影响着农村生态环境质量。本文以石羊河下游484户农户的问卷调查为基础,采用多独立样本和数据包络分析(DEA)法分析不同区域和不同类型农户土地利用行为的差异性和土地利用效率及影响因素。结果表明:(1)越向石羊河尾闾,粮食作物的种植比例越小,而经济作物种植比例越大;(2)坝区种植多样化指数最高,湖区农户土地的投入和产出最高,坝区与湖区土地利用的综合技术效率和规模效率均高于泉山区;(3)随着非农化水平的提高,农兼户的种植多样化指数最高,纯农户、农兼户和兼农户的土地投入与产出、综合技术效率、规模效率依次降低;(4)家庭规模、户主年龄、非农业收入与土地利用效率呈显著负相关性,劳动力受教育水平、农业总投入、农业收入与土地利用效率呈显著正相关性。最后,提出改善石羊河下游农户的土地利用行为、提高土地利用效率的对策建议。  相似文献   

9.
This article examines the interaction between conditions of vulnerability and a potato crop boom in Central Java's highlands. While partaking in agricultural endeavours on volcanic slopes can bring substantial economic rewards, the local benefits associated with these livelihood activities are often overlooked by disaster scholarship. Drawing on a period of fieldwork conducted in the Dieng Plateau, a region characterized by a series of craters that periodically erupt mud and poisonous gas, this article demonstrates how a potato crop boom has evolved despite, and in part because of, the underlying volcanic hazard. By integrating the sustainable livelihood and agrarian change literatures, the article concludes that the potato boom has provided significant economic opportunity, and through this, a means to reduce vulnerability. Yet, despite these economic gains, the agrarian shift described herein has also introduced new vulnerabilities as farmers have become dependent on a resource intensive crop. These findings demonstrate how theories of agrarian transformation can complement livelihood perspectives in disaster research, and provide greater detail into the local and regional processes that encourage people to often-profitably farm hazardous land.  相似文献   

10.
青藏高原几个主要环境因子对植物的生理效应   总被引:15,自引:1,他引:14  
青藏高原作物生育期间的太阳辐射及其强度,均高于我国内地,而且短波辐射比例大,光照时间长,不仅直接影响植物的光合作用、呼吸作用等重要代谢过程,而且不同光质对高原植物植株的生长高度、根系的萌生发育、叶绿素含量以及碳水化合物、蛋白质、脂肪等贮藏物质的积累等方面都有不同的影响。昼夜温差大这一环境特点与高原作物高产之间的关系尚存争议,但对作物的品质确实具有明显的影响作用。在高海拔、低气压(低CO2含量、低O2含量)条件下,植物表现出光合作用光饱和点升高、光补偿点降低、适温偏低,暗呼吸速率较低等特点,因而有利于植物充分利用光能,也有利于植物体内干物质的积累,而且高海拔对植物体内不同代谢成分的形成具有不同的影响作用。虽然青藏高原的多个环境因子,如太阳强辐射、蓝紫光成分多、昼夜温差大等,对高原小麦的高产来说不可缺少,但平均气温较低导致的高原地区小麦生育期明显延长是其干物质产量和籽粒产量高于平原地区的主要原因。  相似文献   

11.
Crop diversity (e.g. the number of agricultural crop types and the level of evenness in area distribution) in the agricultural systems of arid Central Asia has recently been increased mainly to achieve food security of the rural population, however, not throughout the irrigation system. Site-specific factors that promote or hamper crop diversification after the dissolvent of the Soviet Union have hardly been assessed yet. While tapping the potential of remote sensing, the objective was to map and explain spatial patterns of current crop diversity by the example of the irrigated agricultural landscapes of the Fergana Valley, Uzbekistan. Multi-temporal Landsat and RapidEye satellite data formed the basis for creating annual and multi-annual crop maps for 2010–2012 while using supervised classifications. Applying the Simpson index of diversity (SID) to circular buffers with radii of 1.5 and 5 km elucidated the spatial distribution of crop diversity at both the local and landscape spatial scales. A variable importance analysis, rooted in the conditional forest algorithm, investigated potential environmental and socio-economic drivers of the spatial patterns of crop diversity. Overall accuracy of the annual crop maps ranged from 0.84 to 0.86 whilst the SID varied between 0.1 and 0.85. The findings confirmed the existence of areas under monocultures as well as of crop diverse patches. Higher crop diversity occurred in the more distal parts of the irrigation system and sparsely settled areas, especially due to orchards. In contrast, in water-secure and densely settled areas, cotton-wheat rotations dominated due to the state interventions in crop cultivation. Distances to irrigation infrastructure, settlements and the road network influenced crop diversity the most. Spatial explicit information on crop diversity per se has the potential to support policymaking and spatial planning towards crop diversification. Driver analysis as exemplified at the study region in Uzbekistan can help reaching the declared policy to increase crop diversity throughout the country and even beyond.  相似文献   

12.
13.
In the highlands of northern Ethiopia, degraded hillslopes are closed for grazing and agriculture for environmental rehabilitation. In order to assess the effect of these exclosures on water balances, a correct assessment of evapotranspiration is needed. A common method for calculating evapotranspiration employs the reference evapotranspiration in combination with a crop coefficient. However, for natural vegetation, these crop coefficients are not readily available. Therefore, the objective of this study was to derive crop coefficients for semiarid natural vegetation using two different approaches. The crop coefficients were assessed with the dual crop coefficient approach as outlined in the FAO Irrigation and Drainage Paper n°56 and compared with crop coefficients derived from a simple soil water balance. A good agreement between both methods was found. The mid-season crop coefficients ranged from 0.50 to 0.85 for open vegetation with small shrubs and from 0.85 to 0.95 for well developed shrubland. Vegetation with a closed tree canopy was characterized by a mid-season crop coefficient between 0.95 and 1.1. Additionally, a significant logarithmic relation between vegetative soil cover and crop coefficient was found. Using this relation, crop coefficients can be easily derived for semiarid shrub savannahs in similar environments and used for the calculation of evapotranspiration.  相似文献   

14.
Land fallow is of great significance for undertaking land reclamation, safeguarding national food security, promoting environmental improvements and ensuring the sustainable use of land resources. This paper reviews the important achievements in three areas of research on the land fallow system. It reviews and compares the land fallow system in different countries and regions of the world; it examines the response of farmers to the land fallow system and ecological environment; and it looks at the economic effects of the land fallow system. Based on China's rotation system for cultivated land, some relevant policy implications are put forward. Based on the different degrees of land damage, the evaluation system and the subsidy accounting standard for fallow land are formulated, and the compulsory fallow and voluntary participation of the niche fallow are targeting. The land fallow system should improve both the regulatory and the restraint mechanisms, improve the environmental awareness and environmental protection skills of farmers, change the production behaviors of farmers, and encourage farmers to change to high coverage crops to protect the land. In view of the negative effects produced by implementation of the fallow system should take corresponding management and compensation measures.  相似文献   

15.
Most farmers in the Ethiopian highlands depend on rain‐fed agriculture. Some areas have the favourable situation of having two rainy seasons, Belg (February‐May) and the long rainy season Kiremt (June‐October), which is the case in some parts of South Wollo. Tef (Eragrostis tef) is the staple crop that farmers prefer to grow and the 90‐day variety is suitable for growing during the short rainy season. One out of eight Ethiopians lives in tef potential areas which have Belg rainfall. The aim in this study is to analyse rainfall variation in South Wollo, in particular the area east of the small town of Hayk, and to study its effect on the ability to grow tef during the Belg season. Results from interviews showed that a more difficult farming situation had emerged during the past 40 years, largely due to deterioration of physical resources such as rainfall. Rainfall is analysed by comparing daily rainfall data from four stations in two periods, 1963 to 1982 and 1984 to 2003, for changes in totals, seasonal distribution and variability. Coefficient of variance, rainy days, rainfall intensity and dry spells were analysed. Results from this study show that there have been minor rainfall changes but greater rainfall variability. During fieldwork key informants were asked if they were able to harvest tef during the past nine years, a period that has been used in a model of rainfall influence on tef cultivation during the Belg season. In both 20–year periods, farmers were able to grow tef every second year. In spite of a greater variability in rainfall the farmers proved their knowledge and flexibility and were able to harvest tef in the same number of years during both periods.  相似文献   

16.
Soil erosion has become a serious environmental problem worldwide, and slope land is the main source of soil erosion. As a primary cover of slope land, crops have an important influence on the occurrence and development of runoff and soil erosion on slope land. This paper reviews the current understanding of runoff and soil erosion on slope cropland. Crops mainly impact splash detachment, slope runoff, and sediment yield. In this review paper, the effects of crop growth and rainfall on the splash detachment rate and the spatial distribution of splash detachment are summarized. Crop growth has a significant impact on runoff and sediment yield. Rainfall intensity and slope gradient can influence the level of erosive energy that causes soil erosion. Furthermore, other factors such as antecedent soil water content, soil properties, soil surface physical crust, and soil surface roughness can affect soil anti-erodibility. The varying effects of different crops and with different influence mechanisms on runoff and soil erosion, as well as changes in their ability to influence erosion under different external conditions should all remain focal points of future research. The effect of crop vegetation on runoff and soil erosion on slope land is a very important factor in understanding large-scale soil erosion systems, and in-depth study of this topic is highly significant for both theory and practice.  相似文献   

17.
The Sahel has been subject of considerable environmental research and development efforts, specifically since the droughts of the 1970s and 1980s. This article uses a meta-study approach to summarize knowledge of crop land change, the documented driving forces, and the perceived impacts. The analysis of case studies shows that crop land has increased in the majority of cases mainly due to population increase. However, despite population increase, crop land has been stable in some areas, particularly where land availability is a limiting factor or where farmers are able to intensify their farmers from expanding their plots or because households have diversified their activities. The study shows the huge gap in the scientific literature concerning actual measurements of crop land change in the Sahel, which is in contrast to the attention given to crop land changes in theoretical and policy discourses. On the basis of the poor documentation available on crop land change and the contrasting results observed, we point out the need to exercise caution with regard to simple narratives about crop land change.  相似文献   

18.
Species abundance and habitat distribution are two important aspects of species conservation studies and both are affected by similar environmental factors. Forest resource inventory data in 2010 were used to evaluate the patterns of habitat for target species of Cervidae in six typical forestry bureaus of the Yichun forest area in the Lesser Xing’an Mountains, northeastern China. A habitat suitability index(HSI) model was used based on elevation, slope, aspect, vegetation and age of tree. These five environmental factors were selected by boosted regression tree(BRT) analysis from 14 environmental variables collected during field surveys. Changes in habitat caused by anthropogenic activities mainly involving settlement and road factors were also considered. The results identified 1780.49 km2 of most-suitable and 1770.70 km2 of unsuitable habitat areas under natural conditions, covering 16.38% and 16.29% of the entire study area, respectively. The area of most-suitable habitat had been reduced by 4.86% when human interference was taken into account, whereas the unsuitable habitat area had increased by 11.3%, indicating that anthropogenic disturbance turned some potential habitats into unsuitable ones. Landscape metrics indicated that average patch area declined while patch density and edge density increased. This suggests that as habitat becomes fragmented and its quality becomes degraded by human activities, cervid populations will be threatened with extirpation. The study helped identify the spatial extent of habitat influenced by anthropogenic interference for the local cervid population. As cervid species clearly avoid human activities, more attention should be paid on considering the way and intensity of human activities for habitat management as fully as possible.  相似文献   

19.
江西省农户生态耕种采纳意愿与行为悖离研究   总被引:1,自引:0,他引:1  
利用Tobit-ISM模型分析江西省农户生态耕种采纳意愿与行为悖离度影响因素,进一步解析各影响因素间的层次结构。结果表明:70%的农户具有生态耕种意愿,但仅部分农户发生了采纳行为,证实了农户生态耕种采纳意愿与行为发生悖离。通过Tobit回归模型分析文化程度、生态耕种培训、农户态度、耕地面积、生态环境污染认知、环保法规认知、风险认知、相互交流和自然资源状况对悖离度的发生表现出负向作用,而非农收入比重则具有正向影响;通过ISM模型分析农户态度、耕地面积、自然资源状况是表层因素,生态耕种污染认知、环保法规认知、风险认知是中间层因素,文化程度、生态耕种培训、非农收入比重、相互交流是深层次因素。  相似文献   

20.
Cash crop cultivation has been a critical driver of land use change in many countries around the world. However, few efforts have been made to quantify the relationships between cash crop expansion and the subsequent landscape pattern changes. This paper characterized the process of cash crop expansion across Tiaoxi watershed (China) from 1985 to 2009 using multi-sensor and multi-temporal remotely sensed imageries. Correlations were identified between indicators of cash crop expansion (total area and total production of cash crops) and a family of landscape fragmentation metrics (patch density, edge density, landscape division index, effective mesh size, splitting index, Shannon's diversity index, and aggregation index). Results showed that Tiaoxi watershed experienced profound cash crop expansion and progressive landscape fragmentation. The cash crops spread in accessible and productive areas at the expense of paddy and forests. Social drivers of cash crop expansion included population growth, labor structure changes and market incentives. Indicators of cash crop expansion presented linear relationships with landscape fragmentation metrics. These findings evidenced that cash crop cultivation would significantly fragment landscapes. Our study contributed to understanding on the enlarging cultivation of cash crops and the associated modifications of landscape patterns in subtropical regions.  相似文献   

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