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1.
This essay introduces a collection of articles that explore the future of groundwater-based agriculture in the Mediterranean from an interdisciplinary perspective, in a context of declining water tables due to intensive groundwater use. The imminent crisis that many groundwater economies face due to very rapid and intense global change may have severe irreversible social, economic and environmental consequences, but could also be the opportunity to make a clear break with current agricultural development models and move towards more sustainable agricultural practices. The Mediterranean region is, therefore, an interesting case for the future of intensive groundwater use, as innovative ideas and practices may emerge and inspire similar groundwater-based agricultural systems around the world.  相似文献   

2.
Al-Taher  Abdulla Ahmed 《GeoJournal》1992,26(3):371-379
An accurate estimation of the potential evapotranspiration can be achieved ba applying empirical evapotranspiration coefficients which are determined under Al-Hassa prevailing climatic conditions. Correlation coefficient results indicate that most of the climatological variables have a strong relationship with potential evapotranspiration except wind speed and precipition variables which have a weak relationship. Multiple regression results also indicate that there is a significant effect of some of the climatologiecal variables in the potential evatranspiration and there is no significant effect of the others at the significant level of 0.05. The results of the stepwise regression indicate that evaporation class “A” pan, air temperature, sunshine hours, radiation, relative humidity, and wind speed variables have a significant effect at the significant level of 0.05 on the overall mean monthly potential evapotranspiration of the Blaney-Criddle, Pan Evaporation, and Jensen-Haise, therefore, the equation which has developed for estimating potential evapotranspiration in Al-Hassa is based on these six variables (evaporation class “A” pan, air temperature, sunshine hours, radiation, relative humidity, and wind speed).  相似文献   

3.
In Egypt, major sustainability variables could be identified as scarce of soil and water resources, environmental degradation, rapid population growth, institutional arrangement that includes land tenure and farm fragmentation, agricultural administration, lack of infrastructure, and credit utilization. The main objective of the current work is to evaluate the sustainable land use management (SLM) model through biophysics and socioeconomic elements for the purpose of combating sustainability constraints that preclude the agricultural development geospatially. In this research, from the geomorphologic point of view, the obtained results showed three main landscapes. They were identified in the study area as: fluviolacustrine plain, Aeolian deposits, and flood plain. The study area was dominated by some physical and chemical degradation processes with different scales breaking down the equilibrium of soil stability. The SLM model was implemented and assessed from multivariate perspective points of productivity, security, protection, economic viability, and social acceptability. Four SLM classes were outlined as follows: class I, land management practices that did meet sustainability requirements with a score ≥0.65, which represented 31.0 % of the considered agricultural study area; class II, land management practices that were marginally above the sustainability threshold and represented 12.6 %; class III, land management practices that were slightly below the threshold of sustainability and represented 8.60 %; class IV, land management practices that did not meet sustainability requirements with index values >0.1 that represented 47.86 %. As a general conclusion, it is found that land management practices tend to be unsustainable in the area under investigation for certain constraints that play motivated roles in lowering the targeted land sustainability.  相似文献   

4.
In Europe the process of agricultural engagement or disengagement is attributed to the economic factor and mainly on the level of alternative employment source development. It is the relational quality of economic, social and environmental factors that determine sustainability of agricultural holdings and, hence, households. In regions of poor agricultural structures and of many employment opportunities as well as in regions suffering from agricultural depression, households exhibit stronger tendencies towards agricultural disengagement. Remarkably in southern Europe a stable agricultural engagement and not disengagement is observed, even though in recent years there are limited possibilities of alternative income sources and prevailing agricultural depression. This article highlights the factors which lead households to stable engagement with agriculture in a region of southern Europe, the island of Lesvos. The island is characterised by traditional olive grove mono-culture, poor agricultural structures and limited employment opportunities. The investigation of the economic, social and environmental farm household characteristics concluded that in regions where poor agricultural infrastructure and lack of employment prevail, all three factors of sustainability contribute to stability and/or low agricultural disengagement. Among these, the economic factor is the most sensitive and hence highly influential. The social factor is highlighted as a quality and consistent factor due to the respect for tradition. The environmental factor, finally, is characterised by mild cultivation practices, contributing to environment conservation.  相似文献   

5.
The green revolution laid the foundations of modern agriculture, by using science and technology to produce more from same resources. The pesticides contributed to agricultural output in the last decades; however, their use has resulted in environmental pollution, health problems, soil and water contamination and negative impact on biota. The impacts of agricultural activities to the environment depended on the practices adopted during the production process. Measurement tools to assess the impacts of those practices are necessary to improve agricultural systems and must be evaluated in different ecosystems. Different soils, climates and crops impose many phytosanitary arrangements. This complex network and the fact that most of the indicators and measurement tools are developed for temperate climates makes it difficult to quantify the environmental impacts under subtropical regions. The I-Phy index is a predictive indicator that assesses the risks of pesticide usage in agriculture and identifies as to which practices generate the main environmental impacts of pesticides. The objective of this study was to test the suitability of the I-Phy index for subtropical conditions and, if suitable, compare the pesticide risk between two regions. Five crops were assessed under three different cropping systems: no-tillage, minimal tillage and conventional tillage. The I-Phy index was sensitive in both regions and capable of identifying that no-tillage generally presented risks of environmental pollution slightly lower than the other tillage systems. The results of I-Phy index showed that high environmental vulnerability of the fields and the numerous applications of active ingredients with high risks resulted in high risks of general contamination. The application of I-Phy on these two case studies showed the indicator can be useful as a support tool to farmers, research and extension institutions pursuing management practices with lower impact on the environment.  相似文献   

6.
A survey was conducted in 21 rural settlements to assess wildlife conservation under a common utilization. Wildlife was managed through traditional regulations to meet subsistence requirements for food, income, recreation and health care. However, the conditions under which common property resource utilization thrived: traditional beliefs, communal land tenure system and uncertain income streams were almost disintegrated by changes in land use and social attitudes.The resource base for rural economies, the natural vegetation, was in crisis of depletion and degradation due to modern techniques of agricultural and forestry production. A conservative strategy is suggested. Rural land use should be based on planned agroforestry practices: smallholder tree planting, protection and regeneration of indigenous plants with potential social and economic value, domestication of wild animals and ranching of game with livestock.  相似文献   

7.
Nitrogen fertilizer consumption is very common in the agricultural practices. Nitrogen application could be an important source of groundwater N pollution. Normally, nitrogen can pass through the unsaturated zone to pollute the groundwater. Different agricultural practices have different cultivation methods, accordingly different fertilization and irrigation techniques. Hence, the agricultural practice determines the environment of the unsaturated zone, which subsequently determines the extent of groundwater N pollution. To verify the pollution modes and transformation mechanisms of nitrogen, both in situ and laboratory tests were conducted at four different sites to study the effects of agricultural practices on nitrogen distribution in unsaturated zones. The inorganic nitrogen in soil is extracted by potassium chloride solution, and the soil utilization form and pollution type are identified by δ15N by comparing with the known standard values. The experimental results indicate that continual fertilization and sewage irrigation in these agricultural regions were the primary sources of nitrogen in the unsaturated zone. In the soils planted with rice, δ15N–NH4 + was relatively elevated due to ammonium volatilization. In the unsaturated zone of rice–wheat rotation fields, NO3 ?–N and δ15N were both elevated because of manure fertilizer. Meanwhile, denitrification also occurred in the hypoxic environment due to the high soil water content.  相似文献   

8.
The study focusses on the trends of development of land use patterns in th half of the nineteenth century in Punjab and early efforts of the administration to improve the crops raised in the province. It also points out the difficulties faced in the improvement in the agricultural practices of the area. Inter-district variations in agricultural productivity in the province has been determined during this period and the districts have been categorized into four groups on the basis of their level of agricultural development. Regression technique was used to study the causal effect of inputs on the agricultural productivity; discriminate analysis determined inter-group variability.  相似文献   

9.
Sandy Brown  Christy Getz   《Geoforum》2008,39(3):1184-1196
This paper assesses the possibilities and limits of efforts to incorporate social accountability into California agricultural production through voluntary certification and labeling, in the context neoliberal governance. We argue that, in its contradictory role as market mechanism, regulatory form, and social cause, certification both resists neoliberalization of the agro-food system and reinscribes neoliberal thinking. Unlike more traditional forms of social justice organizing, which have historically sought to alter power relations between labor, capital, and the state, the very notion that production conditions can be regulated through voluntary, third-party monitoring and labeling embraces several key neoliberal principles: the primacy of the market as a mechanism for addressing environmental and social ills, the privatization of regulatory functions previously reserved for the public sphere, and the assertion of the individual rights and responsibilities of citizen–consumers. Interviews with certification actors lead us to conclude that the strategic embrace of certification is driven by contradictory motivations within the movement for social accountability in agriculture, which can only be understood in relation to the confluence of a broader neoliberal political–economic order with California’s particular arrangements of farm labor politics and agro-food activism. Specifically, agro-food consolidation, rollback of protective labor regulation, the evisceration of the farm worker movement, and the conservative agrarianism of the sustainable agriculture movement intersect to circumscribe the realm of possibility and create conditions that undermine farm worker representation in the governance of agricultural labor practices.  相似文献   

10.
Effective natural resource management requires interrelated technical practices and social arrangements that are appropriate to a region’s biophysical characteristics and that address protection and sustainable management of resources. This is illustrated from our experience in the Republic of Niger, West Africa. In 1980 barren plains, infertile soils, drought, dust storms, severe fodder shortages, and agricultural pest outbreaks were normal occurrences in Niger’s rural regions. In general, despite large investments of time and funding, conventional reforestation efforts had little impact. However by 2008 over five million hectares of once barren land had been transformed through wide adoption of an agroforestry method known as ‘Farmer Managed Natural Regeneration’ (FMNR), introduced in 1983. In the Aguie Department, the practice of FMNR was formalized through the Desert Community Initiative (DCI), addressing interrelated technical and social issues in resource management. New governance structures, which include marginalized groups, implement monitoring and enforcement systems enabling communities to manage land and regenerating trees. These, together with technical solutions that build on local knowledge and skills and use previously undervalued indigenous tree species, have generated a sustainable fuel-wood market for the first time. Increased linkage and compatibility between institutions at local and national levels and strengthened social capital have been crucial to these impacts. Food security and community resilience to drought have been markedly enhanced and local incomes have increased. The experience provides important lessons for approaches to addressing environmental degradation and poverty in other semi arid areas and facilitating the spread and adoption of new agroforestry systems.  相似文献   

11.
Current theorising in human geography draws attention to the relational emergence of space and society, challenging ideas of difference that rely on fixed identities and emphasising the importance of the everyday in the production of social inequalities. Similarly, feminist political ecology has emphasised the role of ‘nature’ or ‘environment’ in the production of subjectivities such that ideas of gender and nature arise in relation to each other. In this paper I build from these insights to explore the ways in which the embodied performance of gender, caste and other aspects of social difference collapse the distinction between the material and the symbolic. Symbolic ideas of difference are produced and expressed through embodied interactions that are firmly material. Through this kind of conceptualisation, I hope to push forward debates in geography on nature and feminist political ecology on how to understand the intersectional emergence of subjectivities, difference and socio-natures. Importantly, it is the symbolic meanings of particular spaces, practices and bodies that are (re)produced through everyday activities including forest harvesting, agricultural work, food preparation and consumption, all of which have consequences for both ecological processes and social difference. Through the performance of everyday tasks, not only are ideas of gender, caste and social difference brought into view, but the embodied nature of difference that extends beyond the body and into the spaces of everyday life is evident. I use ethnographic evidence from rural Nepal to explore the ways in which boundaries between bodies, spaces, ecologies and symbolic meanings of difference are produced and maintained relationally through practices of work and ritual.  相似文献   

12.
Papers presented at a two-day jointly sponsored IAHS/AGU symposium on groundwater contamination are briefly summarized. This international symposium was held 11–12 May, 1989, in Baltimore, Maryland. Presentations encompassed recent research developments in three general areas: abiotic and biotic processes governing contaminant transport; aquifer rehabilitation; and the influence of agricultural practices and nonpoint sources on aquifer quality. Contributions offered an interesting mixture of theoretical, mathematical, laboratory, and field studies. In the first session, transport processes explored ranged from dispersion and fingering to nonequilibrium sorption, metals complexation, and bacteria migration. The use of optimization modeling in the design of remediation strategies was the focus of another session. Here theoretical studies were presented alongside case histories of aquifer rehabilitation. In a final session, a number of models for agricultural management were described. These presentations were complemented by case studies of actual aquifer degradation resulting from land-use and management practices.  相似文献   

13.
Desertification in areas where traditional pastoral nomadism was common is a phenomenon of this century. Nomads possessed institutions and management practices that avoided excess concentrations of people and animals, rotated grazing pressure seasonally between major pasture zones, protected dry season resources that were critical to their survival, and limited access to pastoral resources. These systems of management and control have broken down and degradation of pastoral lands has been the result. The pressures promoting desertification include agricultural expansion into pastoral zones, the loss of critical dry season pasture, sedentarization of former nomads, the impacts of war and civil conflict, nationalization of pastoral resources, the collapse of traditional common property resource management systems, and social change and economic intensification. These processes have concentrated pastoral pressures into more limited spaces and increased the stress placed on natural resources to the point where land degradation takes place. These adverse changes can be avoided and desertification arrested if principles of proper management are applied. By planning holistically, using the ethnoscientific wisdom of nomadic pastoralists as a basis for development, protecting zones critical to the survival of pastoralists, retaining mobility and flexibility in contemporary pastoral systems, and strengthening common property systems developed by nomadic pastoralists, land degradation in dryland rangelands can be halted.  相似文献   

14.
This paper considers Swiss experiences of in situ agrobiodiversity conservation. The Swiss recognise the multifunctionality of agriculture, particularly within the marginal, mountainous areas of the country and are spending public and private funds to maintain crop landraces, agroecosystems, landscapes, agricultural practices, and rural communities. State programs in marginal agricultural regions tie economic assistance to biodiversity conservation practices, through the use of direct payment systems. With the removal of many import restrictions and state-led marketing, alternative innovative programs linked to local values of diversity provide opportunities for conservation. In situ agrobiodiversity conservation ideas being pursued include awareness-raising schemes, scientific initiatives, the establishment of diversity gardens and community-based programs. Any extension of the in situ conservation programs could have substantial implications for regional development. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
The 26 December 2004-tsunami has deposited sediments in the Pichavaram mangrove ecosystem, east coast of India. Ten surface and three core sediment samples were collected within 30 days of the event and analyzed for nutrients. Water samples were also analyzed to see the impact of tsunami on the geochemical behavior of nutrients. An increase in the concentration of various nutrients namely nitrate and phosphate was observed. The geochemistry of the mangrove forest was observed to be influenced by a number of factors like rapid increase of aquaculture farms, agricultural practices and the anthropogenic discharge from the nearby-inhabited areas. Further the sediment column was disturbed due to energetic tsunami waves, which has caused a sheer increase in the dissolved oxygen in water. As a result, the change in the redox potential has resulted in change in the nutrients absorbed/associated with the sediments. In addition, role of retreating water after tsunami on the nutrient geochemistry was also evaluated.  相似文献   

16.
Despite rapid economic growth, India has not seen the improvements in food and nutritional security that other developing countries have had. This “Asian enigma” has generated a wealth of economistic analyses seeking to explain the persistence of poor nutrition, yet few studies have looked at everyday experiences of changing food systems, and how this impacts nutritional practices as well as the processes of subject formation. In this paper, I draw on qualitative research conducted in Uttarakhand, North India and examine how state-led shifts in agricultural production have resulted in changing food consumption practices and diminished perceptions of health. Villagers link this decreased health to increased chemicals in home-produced food, greater dependence on the market for food purchases, and generational changes in dietary preferences. Despite villagers’ cognizance of the negative health effects of these practices, they largely view these byproducts of capitalistic development with an air of inevitability. Following Mansfield (2011) this paper contributes to the political ecology of health literature by employing the concept of food as a “vector of intercorporeality” (Stassart and Whatmore, 2003:449) and bringing this into conversation with a poststructuralist understanding of subjectivity. I argue that within shifting landscapes of agriculture production and food consumption, notions of diminished health are indicative of the complex and always incomplete processes of subject formation. I view shifting health perceptions as intimate bodily resistances to agricultural development, and conclude that within agricultural development programs a focus on bodily health and well-being is a fecund platform for further experimental research that seeks to imagine development differently.  相似文献   

17.
This paper explored the status of climate-smart agriculture (CSA) in southeast Nigeria using qualitative and quantitative methods in data collection. One hundred and sixty farmers were selected from the area. Also, focus group discussions were conducted. Data collected were subjected to qualitative analysis and logit regression. The study identified five broad and important practices relevant to CSA in southeast Nigeria, which include: adjusting agricultural production systems, mobility and social networks, farm financial management, diversification on and beyond the farm, and knowledge management and regulations. The determinants of CSA in southeast Nigeria include: education, income, credit, extension, livestock ownership, farming experience, land area cultivated, distance to the market and water resources, leadership position, risk orientation, gender, land ownership, household size, and mass media exposure. Government policies need to support research and development that develops and diffuses the climate-smart technologies to help farmers respond changes in climatic conditions.  相似文献   

18.
Tetramethylthiuram disulfide is a widely used pesticide and a soil treatment agent in the agricultural sector. Consequently, its detection in the environment and investigation of the distribution between the aqueous and soil phases would be of highly importance. In this study, the detection of tetramethylthiuram disulfide in CHCl3 was successfully achieved through absorbance measurements at 280 nm, which resulted in linear calibration curves. This detection method was extended for the determination of the partition coefficient (KD) of tetramethylthiuram disulfide between CHCl3 and H2O phases at ambient temperature. The partition coefficient was subsequently used to determine the apparent partition coefficient (KD) of tetramethylthiuram disulfide between sieved soil of diamater < 2.0 mm used for agricultural practices and water where by the quantification of tetramethylthiuram disulfide in water after adsorption equilibrium with soil was achieved through a solvent extraction step of tetramethylthiuram disulfide-contaminated water into CHCl3. The KD determined for an initial tetramethylthiuram disulfide concentration ranging from 3.00 ppm to 10.00 ppm showed a decreasing trend, which leveled off at high concentrations, indicating the strong irreversible adsorption behavior of tetramethylthiuram disulfide on soil at low concentrations. The proposed detection method would have the potential to determine the extent of adsorption of tetramethylthiuram disulfide in soil or its levels in water when tetramethylthiuram disulfide is introduced to soil systems for agricultural practices.  相似文献   

19.
节水农业体系及节水潜力分析   总被引：2，自引：0，他引：2  
根据有关文献及工作实践,论述了节水农业体系及其具体内涵.节水农业一般应包括农业水资源的合理开发利用、节水灌溉工程、农业耕作栽培节水及节水管理技术.节水农业是包含多种技术措施的一套完整的技术体系.发展节水农业不但能够节约和挖潜出巨大的农业水资源量,而且其增产增收效果也十分明显.同时也有利于农业种植结构调整,促进传统农业向...  相似文献   

20.
The 800 cm long sequence from the Bereket provides the first detailed fire history in the western Taurus Mountains for the last three millennia. The main disturbances occurred during the Bey?ehir Occupation Phase (BO Phase), a period of intensive polyculture and dated at Bereket from ca. 2230 to 1550 cal yr BP. Four phases of local and extra-local fire periods have been recorded at 2320-2240, 1985-1970, 1865-1820 cal yr BP and post-AD 1950. The fire history established for the BO Phase is complex, with fire periods alternating with periods without local fires, as is the case for the late BO Phase from 1820 until 1550 cal yr BP. It is suggested that the past agricultural practices including fires cause a higher soil erodibility than agricultural practices without fires. A climatic shift towards aridity during Roman times may have triggered the observed change in fire regime but local processes, mainly human disturbances, appear to be the proximal cause of all recorded changes. In the Bereket surroundings, fires led to a simplification of the vegetation structure, favouring soil erosion, pastures and intensive cultivation.  相似文献   

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