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271.
Are farmers in England equipped to meet the knowledge challenge of sustainable soil management? An analysis of farmer and advisor views 总被引:1,自引:0,他引:1
Ingram J 《Journal of environmental management》2008,86(1):214-228
Concern about the agricultural soil resource in England has led to the introduction of a range of measures, which potentially challenge farmers' knowledge about the soil and its management. Our understanding however of how well-equipped farmers are with regard to effectively carrying out more complex and knowledge intensive sustainable soil management practices is limited. Specifically, by drawing on the concept of scientific and tacit forms of knowledge, this paper examines the knowledge of soils held by farmers through analysis of data collected from semi-structured interviews with farmers and agricultural advisors and supplemented with data from an extensive postal questionnaire survey of advisors. The data indicate that, while farmers are technically well informed, they can often lack the in-depth scientific knowledge required to implement more complex practices such as using the nutrient value of manures. They also reveal that, while most farmers have good knowledge of their own soils, their tacit knowledge of soil management can be weak, notably in relation to cultivation. The paper concludes that although farmers' knowledge about soil and its sustainable management appears in general to be well developed there are some areas, which need to be significantly enhanced and as such require both a policy response and further research effort. 相似文献
272.
The tsunami of 26 December 2004 struck the Nagapattinam District, Tamil Nadu, India. Sea water inundation from the tsunami caused salinization problems for soil and groundwater in coastal areas of the district, and also induced salt injuries in crops. To document the recovery of the agricultural environment from the tsunami, we conducted observations of the soil, groundwater, and vegetation. Soil electrical conductivity increased sharply after the tsunami, but returned to pre-tsunami levels the following year. Groundwater salinity returned to pre-tsunami levels by 2006. These rapid rates of recovery were due to the monsoon rainfall leaching salt from the highly permeable soils in the area. MODIS NDVI values measured before and after the tsunami showed that vegetation damaged by the tsunami recovered to its pre-tsunami state by the next rice cropping season, called samba, which starts from August to February. From these results, we conclude that the agricultural environment of the district has now fully recovered from the tsunami. Based on the results, we have also identified important management implications for soil, groundwater, and vegetation as follows: 1) due to the heavy monsoon rainfall and the high permeability of soils in this region, anthropogenic inputs like fertilizers should be applied carefully to minimize pollution, and the use of green manure is recommended; 2) areas that were contaminated by sea water extended up to 1000 m from the sea shore and over pumping of groundwater should be carefully avoided to prevent inducing sea water intrusion; and 3) data from a moderate resolution sensor of 250 m, such as MODIS, can be applied to impact assessment in widespread paddy field areas like the Nagapattinam District. 相似文献
273.
Much of Sub‐Saharan Africa is burdened with water scarcity and poverty. Continentally, less than four percent of Africa's renewable water resources are withdrawn for agriculture and other uses. Investments in agricultural water management can contribute in several ways to achieving the Millennium Development Goals of eradicating extreme poverty and hunger and ensuring environmental sustainability. Increased yield and cropping area and shifts to higher valued crops could help boost the income of rural households, generate more employment, and lower consumer food prices. These investments can also stabilize output, income and employment, and have favourable impacts on education, nutrition and health, and social equity. Investments in agricultural water management can cut poverty by uplifting the entitlements and transforming the opportunity structure for the poor. The overall role of investments in agricultural water management in eradicating hunger and poverty is analyzed. This paper contributes to the present debate and efforts to identify strategies and interventions that can effectively contribute to poverty reduction in Africa. It provides an overview of population growth, malnutrition, income distribution and poverty for countries in three case study river basins — Limpopo, Nile, and Volta. With discussions on the contribution of agriculture to national income and employment generation, the paper explores the linkages among water resources investments, agricultural growth, employment, and poverty alleviation. It examines the potential for expansion in irrigation for vertical and horizontal growth in agricultural productivity, via gains in yield and cropping area to boost the agricultural output. Factors constraining such potential, in terms of scarcity and degradation of land and water resources, and poor governance and weak institutions, are also outlined. The paper argues that increased investments in land and water resources and related rural infrastructure are a key pathway to enhance agricultural productivity and to catalyze agricultural and economic growth for effective poverty alleviation. 相似文献
274.
Adoption and adaptation of natural resource management innovations in smallholder agriculture: reflections on key lessons and best practices 总被引:2,自引:0,他引:2
Bekele A. Shiferaw Julius Okello Ratna V. Reddy 《Environment, Development and Sustainability》2009,11(3):601-619
Many smallholder farmers in vulnerable areas continue to face complex challenges in adoption and adaptation of resource management
and conservation strategies. Although much has been learned from diverse experiences in sustainable resource management, there
is still inadequate understanding of the market, policy and institutional failures that shape and structure farmer incentives
and investment decisions. The policy and institutional failures exacerbate market failures, locking smallholder resource users
into a low level equilibrium that perpetuates poverty and land degradation. Improved market access that raises the returns
to land and labor is often the driving force for adoption of new practices in agriculture. Market linkages, access to credit
and availability of pro-poor options for beneficial conservation are critical factors in stimulating livelihood and sustainability-enhancing
investments. Future interventions need to promote joint innovations that ensure farmer experimentation and adaptation of new
technologies and careful consideration of market, policy and institutional factors that stimulate widespread smallholder investments.
Future projects should act as ‘toolboxes’, giving essential support to farmers to devise complementary solutions based on
available options. Addressing the externalities and institutional failures that prevent private and joint investments for
management of agricultural landscapes will require new kinds of institutional mechanisms for empowering communities through
local collective action that would ensure broad participation and equitable distributions of the gains from joint conservation
investments.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
275.
Vulnerability and adaptation of European farmers: a multi-level analysis of yield and income responses to climate variability 总被引:6,自引:3,他引:3
Pytrik Reidsma Frank Ewert Alfons Oude Lansink Rik Leemans 《Regional Environmental Change》2009,9(1):25-40
Climate change will affect crop yields and consequently farmers’ income. The underlying relationships are not well understood,
particularly the importance of crop management and related factors at the farm and regional level. We analyze the impacts
of trends and variability in climatic conditions from 1990 to 2003 on trends and variability in yields of five crops and farmers’
income at farm type and regional level in Europe considering farm characteristics and other factors. While Mediterranean regions
are often characterized as most vulnerable to climate change, our data suggest effective adaptation to variable and changing
conditions in these regions largely attributable to the characteristic farm types in these regions. We conclude that for projections
of climate change impacts on agriculture, farm characteristics influencing management and adaptation should be considered,
as they largely influence the potential impacts. 相似文献
276.
Rapid increase in industrialization and agricultural activities to meet the population need has led to environmental pollution.
The major revolution in agricultural production is mainly due to increased use of pesticides and fertilizers. Soil act as
a major sink for majority of pesticides applied on agricultural crops. Among the organochlorines, endosulfan is the most commonly
used pesticide, hence this study concentrates on the persistence and distribution behaviour of endosulfan under field conditions.
The result showed that the alpha endosulfan concentrations were very minimum (0.98 mg/kg of soil) in all the four fields under
study (Nazarath, Othikadu, Ekkadu and Ekkadukandigai of Thiruvallur district, Tamil Nadu). Where as beta endosulfan concentration
at the time of application was 6.39 mg/kg and declined to 0.8 mg/kg on soil at 150th day. The endosulfan sulfate concentration
was 11.8 mg/kg in soil at 15th day and then concentration declined to 2.2 mg/kg at 150th day. Field run-off samples showed
maximum residue levels (0.024 mg/l) at the early irrigation period. While plant foliar parts showed maximum concentrations
of α-endosulfan (43.4 mg/kg), β-endosulfan (40.6 mg/kg) and endosulfan sulfate (20.1 mg/kg). At harvest stage, rice grain and husk also had lower concentrations of endosulfan sulfate (2.2 and 0.09 mg/kg), respectively. 相似文献
277.
生物接触氧化与兼氧水解-Bardenpho脱氮工艺应用于农用抗生素废水处理的比较分析 总被引:3,自引:0,他引:3
农用抗生素废水不仅有机物、氨氮、SS和盐分含量高,还含有不可降解的结构复杂的有机物、发酵中间代谢产物及抗生素,属高浓度难降解有机废水.对浙江钱江生物化学股份有限公司的农用抗生素废水一、二期工程的水质特点、工艺流程、运行情况和技术经济进行了比较分析,结果表明:采用单级生物接触氧化为主的处理工艺,生化残余浓度高,达标困难;采用兼氧水解-Bardenpho脱氮工艺处理,不仅能有效降低生化残余浓度,且系统对COD和氨氮的去除率分别达到98%和99%以上,且运行费用降低40%,获得的社会效益和环境效益较显著. 相似文献
278.
本溪县农业面源污染现状及防治对策 总被引:4,自引:1,他引:3
通过科学的调研数据,重点分析了本溪县农药、化肥和农膜造成的环境污染。调查结果表明,本溪县农药、化肥和农膜的大量施用,虽然可以提高农作物的产量,但也会对人、土地、水体和生物等产生诸多不利的影响,从而提出相应的治理对策。建议发展生态农业,加强监督管理,研究制定相应的污染控制政策与措施。 相似文献
279.
农业文化遗产保护目标下农户生计状况分析 总被引:2,自引:0,他引:2
农户生计是农业文化遗产认定标准之一,也是影响农业文化遗产保护与传承的关键因素,在贫困地区,遗产保护与农户脱贫的两难困境更为突出。本研究基于可持续生计理论和分析框架,以全球重要农业文化遗产地——云南红河哈尼稻作梯田为案例区域,通过生计资本指标体系构建和量化,对比分析了不同生计途径农户的生计状况。评估结果发现,农户的生计资本均值为2.312,生计资本处于匮乏状态,金融资本值最低,而文化资本值最高。从事农业和打工是当前农户的主要生计途径,旅游接待成为生计拓展的重要形式。三类农户生计资本值和家庭年均收入排序相同,都表现为旅游接待户打工兼业户纯农业户,纯农业户的生计状况最差。从单项生计资本看,旅游接待户和打工兼业户的人力资本显著高于纯农业户,物质资本和金融资本比较中,旅游接待户显著高于其他两类农户,说明人力资本越丰富的农户越可能倾向于兼业,农户开展旅游接待需要较高的物质和金融资本作为基础。这意味着,农业文化遗产保护要大力提高农户的农业经营收益,延长农业的价值链和产业链,完善农村金融市场,开展旅游接待培训,从人力、金融等多方面改善农户生计资本状况,实现生计途径拓展。 相似文献
280.
ABSTRACT In forest frontiers, smallholder agrarian livelihoods remain uneasily juxtaposed with conservation interests. Agricultural intensification is often considered a viable means of reconciling competing environmental and livelihood objectives given its potential to concentrate production on less land. However, intensification may have unintended consequences, including loss of resilient agricultural systems. The risks of smallholder agricultural intensification warrant a better understanding of its drivers. This study uses the case of Calakmul, Mexico, to examine the critical role of the state in intensification processes. Drawing on household surveys and key-informant interviews, it traces the linkages between state institutions and local farming practices. Statistical and qualitative analyses reveal how intensification is both incentivized and imposed by prevailing policies, the former via subsidies and the latter via regulations against field rotations. The outcome – increased external inputs and longer cultivation periods between fallows – may undermine the sustainability of smallholders’ agroecosystems, an undesirable consequence amid limited livelihood alternatives. 相似文献