Evolution Rules of Urban-rural Development and Inspiration for China＇s Agriculture

Based on urban-rural contrast coefficient, this article designs the agriculture relative development index （ARDI） as indicators measuring the intensity of urban rural dual structure which is comparable among the countries of the world. This article calculates ARDI of 40 countries from 1980 to 2004. The result shows that ARDI in the developed countries and most of the middle-income countries are rising and yet there are declines in most of the low-income countries. The result also showed that most countries＇ ARDI will see a decline at the earlier stage of industrialization, so their dual economic structure will also aggravate and urban-rural gap will widen. With the economic development, the tendency will change and ARDI presents a U-shape change overall. The turning point is when a country becomes a middle-income one.     

Study on the Circular Agriculture Development in Beijing’s Mountain Areas

Circular agriculture is an essential way to realize the positive recycling of ecology and harmonious development of the country construction.The sustainable development of Beijing’s mountain areas depends on the background and orientation of ecological economy.Beijing’s mountain areas bear the responsibility of protecting the ecological safety of the whole Beijing district and also the exploration of circular agriculture in mountain areas is very important to promote the sustainable use of agriculture resou...     

Multicriteria decision-making for efficient water and land resources allocation in irrigated agriculture

The irrational use of water in agriculture is often responsible for several problems concerning the depletion and/or the pollution of water resources. In these cases specific policy measures should be taken to protect water resources from harmful agricultural activities, mitigating at the same time their potential impact on farmers’ welfare. To this end, a multicriteria decision-making model is formulated that aims at allocating efficiently water and land resources in a rural area of Greece, by optimizing a set of important socio-economic and environmental objectives. According to the model’s output, past and current decisions on irrigated agriculture turned out to be oriented towards meeting exclusively the socio-economic objectives. Yet, there are several other possible allocations schemes that could be applied in order to improve the performance of environmental indicators and to contribute to a more sustainable use of natural resources. Moreover, the decision-making model can be further employed to assess a number of additional policy measures in irrigated agriculture. In this framework, the outcome of imposing various water pricing policies was evaluated. The efficiency of these policies was found tightly connected to the elasticity of water demand. Namely, higher elasticity seems to enhance the flexibility in resource allocation and the movement towards environmental objectives. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Mason Valley Groundwater Model: Linking Surface Water and Groundwater in the Walker River Basin,Nevada1

Carroll, Rosemary W.H., Greg Pohll, David McGraw, Chris Garner, Anna Knust, Doug Boyle, Tim Minor, Scott Bassett, and Karl Pohlmann, 2010. Mason Valley Groundwater Model: Linking Surface Water and Groundwater in the Walker River Basin, Nevada. Journal of the American Water Resources Association (JAWRA) 46(3):554-573. DOI: 10.1111/j.1752-1688.2010.00434.x Abstract: An integrated surface water and groundwater model of Mason Valley, Nevada is constructed to replicate the movement of water throughout the different components of the demand side of water resources in the Walker River system. The Mason Valley groundwater surface water model (MVGSM) couples the river/drain network with agricultural demand areas and the groundwater system using MODFLOW, MODFLOW’s streamflow routing package, as well as a surface water linking algorithm developed for the project. The MVGSM is capable of simulating complex feedback mechanisms between the groundwater and surface water system that is not dependent on linearity among the related variables. The spatial scale captures important hydrologic components while the monthly stress periods allow for seasonal evaluation. A simulation spanning an 11-year record shows the methodology is robust under diverse climatic conditions. The basin-wide modeling approach predicts a river system generally gaining during the summer irrigation period but losing during winter months and extended periods of drought. River losses to the groundwater system approach 25% of the river’s annual budget. Reducing diversions to hydrologic response units will increase river flows exiting the model domain, but also has the potential to increase losses from the river to groundwater storage.     

Urban Agriculture：A Transitional Mechanism for Reducing Environmental Degradation and Fossil Fuel over Dependence

With the increasing population in the urban cities of the world,the demand for food from distant areas has been on the rise but at the expense of scarce natural resources like oil,water and forest,etc.However,producing food locally in urban centers provides a sustainable mechanism of reducing the carbon,food or ecological footprints of these cities in particular and environmental degradation in general.It creates a circular metabolic system in which the natural inputs are efficiently harnessed rather than the linear metabolic system in which resources flow in and wastes flow out.This article analyzes some urban agricultural local initiatives in urban centers of the worlds that promote a circular metabolic systems and proposes the procedure that can be adopted to promote urban agriculture.     

我国集约农业的持续化之路

20世纪70年代以来,国际上先后出现了自然生态农业思潮和可持续农业思潮,引起了我国学术界的广泛讨论与研究。根据河北省景县生产的实际情况,并结合麦玉两熟、水肥耦合试验结果,阐明了中国既不能走"单纯水资源保护型"农业之路,又不能走"单纯防止水资源污染型"农业之路,必须坚定不移地走集约可持续农业之路。     

扬州市农业节能减排的潜力分析

本文结合扬州市农业生产的实际,重点从化肥投入量的控减、农作物秸秆和畜禽粪便的资源化再利用等三个方面,分析扬州市农业节能减排的潜力。结果表明,扬州市农业节能减排的潜力巨大,只要完善相应的节能减排措施,通过农业生产节能和农业生产废弃物的能源化利用,每年可产生330万t煤炭的节能效益。据此,提出了推进扬州市农业节能减排的对策。     

论郊区农业生态环境建设的几个问题

在对郊区环境组成、结构、生态环境特征等区域研究的基础上 ,以边缘效应的理论为出发点 ,深入分析了城乡交错带的几个生态环境建设问题。认为郊区生态建设应以 (1)城市废弃物的再生地 ,(2 )生态旅游与农业文化的消费地 ,(3)现代持续农业的先导区等为目标。最后分析了城乡交错面 (边缘界面 )对城乡复合生态系统中环境应力的聚合放大效应 ,指出效区农业生态环境的调控是防止城乡矛盾激化的根本措施     

论观光农业及其可持续发展的基本策略

观光农业是农业生产和经营形式的创新,是农业和旅游业交叉产生的新产业.本文分析了观光农业的创新意义、开发模式,提出了实现其可持续发展的基本思路.     

Prospects of Biological Resources in Mitigating Agricultural Disasters

1 Meteorological and biological disasters are major constraints to agriculturaldevelopment.1 .1 Meteorological disasters represented by flood and drought and the most serious threat toagricultural production.According to a survey,the average annual droughty farmland for the period 1 95 1～ 1 988wasapproximately 2× 1 0 7hm2 ;the total loss of grain caused by drought disaster only has amountedto1 .5 32 1× 1 0 11kg in the last30 years,accounting for5 0 % of the national total.Meanwhile,China is…