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201.
本文对安徽沿江地下水资源的开发利用与保护进行了论述;把地下水分为地下热水、饮用矿泉水和一般地下水.该文进一步展示了开发利用地下水有利于开发性农业的发展,同时提出了保护地下水资源的对策. 相似文献
202.
Suvi Monni Paula Perälä Kristiina Regina 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):545-571
According to the United Nations Framework Convention on Climate Change (UNFCCC) and Kyoto Protocol under it, industrial countries
have to estimate their greenhouse gas emissions annually, and assess the uncertainties in these estimates. In Finland, agricultural
methane (CH4) and nitrous oxide (N2O) emissions represent 7% of anthropogenic greenhouse gas emissions, and globally the share is much higher. Agriculture is
one of the most uncertain emission categories (representing over 20% of greenhouse gas inventory uncertainty in Finland),
due to both high natural variability of the emission sources and poor knowledge of the emission-generating processes. In this
paper, we present an uncertainty estimate of agricultural CH4 and N2O emissions from Finland in 2002. Uncertainties were estimated based on measurement data, literature and expert judgement,
and total uncertainty in agriculture was calculated using Monte Carlo simulation. According to the calculations, agricultural
CH4 and N2O emissions from Finland were 3.7 to 7.8 Tg carbon dioxide (CO2) equivalents, 5.4 Tg being the mean value.Estimates of CH4 emissions are more reliable than those of N2O. N2O from agricultural soils was the most uncertain emission category, and the uncertainty was not reduced by using available
national measurement data of N2O fluxes. Sensitivity study revealed that the uncertainty in total agricultural inventory could be 7% points lower, if more
accurate emission estimation methods were used, including 1) improved data collection in area estimates of organic soils,
2) climate-specific methods for N2O from agricultural soils as already presented in literature, and 3) more detailed CH4 estimation methods for enteric fermentation which can be achieved by investigating national circumstances and digestible
systems of animals in more detail. 相似文献
203.
开发有机食品促进我省农业可持续发展 总被引:3,自引:0,他引:3
该文通过分析我省发展有机食品的有利及不利因素,提出保证我省有机食品健康发展的对策。 相似文献
204.
农药与未来农业的发展 总被引:6,自引:0,他引:6
评述现代农业生产中使用农药所带来的负面效果,对农作物,畜禽,人体及其他方面所造成的危害,阐明农业生产中减少农药用量,走持续发展道路的现实性和必要性。 相似文献
205.
Venema Henry D. Schiller Eric J. Bass Brad 《Mitigation and Adaptation Strategies for Global Change》1996,1(2):139-165
The ongoing drought in the Sahel region of West Africa highlights the vulnerability of food-producing systems to climate change
and variability. Adaptation to climate should therefore increase the sustainability of agriculture under a long-term drought.
Progress towards sustainability and adaptation in the the Senegal River Basin is hampered by an existing set of social and
ecological relationships that define the control over the means of production and how people interact with their environment.
These relationships are sensitive to the technological inputs and the administration of food production, or the factor bias
in the different policy alternatives for rural development. One option is based on state-controlled, irrigated plantations
to provide rice (Oryza) for the capital, Dakar. This policy emphasizes a top-down management approach, mechanized agriculture and a reliance on
external inputs which strengthens the relationships introduced during the colonial period.
A time series decomposition of the annual flow in the Senegal River at Bakel in Senegal suggests that water resources availability
has been substantially curtailed since 1960, and a review of the water resources budget or availability in the basin suggests
that this policy's food production system is not sustainable under the current climate of the basin. Under these conditions,
this program is exacerbating existing problems of landscape degradation and desertification, which increases rural poverty.
A natural resource management policy offers two adaptation strategies that favour decentralized management and a reduction
of external inputs. The first alternative, “Les Perimetres Irrigués”, emphasizes village-scale irrigation, low water consumption
cereal crops and traditional socio-political structures. The second alternative emphasizes farm-level irrigation and agro-forestry
projects to redress the primary effects of desertification. 相似文献
206.
207.
Leichenko Robin M. O'Brien Karen L. 《Mitigation and Adaptation Strategies for Global Change》2002,7(1):1-18
Research on the agricultural impacts of global change frequently emphasizesthe physical and socioeconomic impacts of climate change, yet globalchanges associated with the internationalization of economic activity mayalso have significant impacts on food systems. Together, climate change andglobalization are exposing farmers to new and unfamiliar conditions.Although some farmers may be in a position to take advantage of thesechanges, many more are facing increased vulnerability, particularly in thedeveloping world. This paper considers the dynamics of agriculturalvulnerability to global change through the example of southern Africa. Wedemonstrate that the combination of global and national economic changesis altering the context under which southern African farmers cope withclimate variability and adapt to long-term change. We find that farmers whoformerly had difficulty adapting to climatic variability may become lessvulnerable to drought-related food shortages as the result of tradeliberalization. At the same time, however, removal of national credit andsubsidies may constrain or limit adaptation strategies of other farmers,leaving them more vulnerable to climate variability and change. 相似文献
208.
Impact of Climate Change on Possible Scenarios for Egyptian Agriculture in the Future 总被引:1,自引:0,他引:1
El-Shaer H. M. Rosenzweig C. Iglesias A. Eid M. H. Hillel D. 《Mitigation and Adaptation Strategies for Global Change》1997,1(3):233-250
If no timely measures are taken to adapt Egyptian agriculture to possible climate warming, the effects may be negative and
serious. Egypt appears to be particularly vulnerable to climate change because of its dependence on the Nile River as the
primary water source, its large traditional agricultural base, and its long coastline, already undergoing both intensifying
development and erosion. A simulation study characterized potential yield and water use efficiency decreases on two reference
crops in the main agricultural regions with possible future climatic variation, even when the beneficial effects of increased
CO2 were taken into account. On-farm adaptation techniques which imply no additional cost to the agricultural system, did not
compensate for the yield losses with the warmer climate or improve the crop water-use efficiency. Economic adjustments such
as the improvement of the overall water-use efficiency of the agricultural system, soil drainage and conservation, land management,
and crop alternatives are essential. If appropriate measures are taken, negative effects of climate change in agricultural
production and other major resource sectors (water and land) may be lessened.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
209.
金华市石门农场自1986年起进行生态实验区建设,将饲养、种植、加工三个子系统有机结合成一个整体,形成以种植业为基础,饲养业为中心,沼气为纽带的能量、物质循环利用的复合型结构,取得了较好的经济和生态效益。从而提出了江南低丘红壤区生态农业建设的一种模式。 相似文献
210.
本文试用持续农业的目标来界定持续农业的内涵。持续农业就是具有农业生产可持续性、经济可持续性、生态可持续性和农村社会可持续性的农业。首先分别阐述了持续农业的4个目标,然后就目标之间的相关与独立关系、轻重缓急关系做了分析 相似文献