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21.
Dairy farms comprise a complex landscape of groundwater pollution sources. The objective of our work is to develop a method to quantify nitrate leaching to shallow groundwater from different management units at dairy farms. Total nitrate loads are determined by the sequential calibration of a sub-regional scale and a farm-scale three-dimensional groundwater flow and transport model using observations at different spatial scales. These observations include local measurements of groundwater heads and nitrate concentrations in an extensive monitoring well network, providing data at a scale of a few meters and measurements of discharge rates and nitrate concentrations in a tile-drain network, providing data integrated across multiple farms. The various measurement scales are different from the spatial scales of the calibration parameters, which are the recharge and nitrogen leaching rates from individual management units. The calibration procedure offers a conceptual framework for using field measurements at different spatial scales to estimate recharge N concentrations at the management unit scale. It provides a map of spatially varying dairy farming impact on groundwater nitrogen. The method is applied to a dairy farm located in a relatively vulnerable hydrogeologic region in California. Potential sources within the dairy farm are divided into three categories, representing different manure management units: animal exercise yards and feeding areas (corrals), liquid manure holding ponds, and manure irrigated forage fields. Estimated average nitrogen leaching is 872 kg/ha/year, 807 kg/ha/year and 486 kg/ha/year for corrals, ponds and fields respectively. Results are applied to evaluate the accuracy of nitrogen mass balances often used by regulatory agencies to assess groundwater impacts. Calibrated leaching rates compare favorably to field and farm scale nitrogen mass balances. These data and interpretations provide a basis for developing improved management strategies.  相似文献   
22.
Many state governments in the United States promote locally-produced farm products. This paper discusses issues related to the ethics and equity of such promotional programs. The paper argues that generic promotion is generally easier to justify in terms of ethics and equity than brand promotion. It also argues that informative and factual brand promotions are easier to justify than deceptive and persuasive brand promotions. Additional equity issues arising when taxpayers finance state-promotional programs are also discussed.  相似文献   
23.
林亦曦 《林业劳动安全》2002,15(3):37-38,40
论述了在新形势下国有林场“三工”安全管理存在的问题,提出了坚持以人为本、以理服人、以情感人、加强企业安全文化建设的“三工”安全管理新机制。  相似文献   
24.
Identifying and mapping community vulnerability   总被引:30,自引:1,他引:29  
Morrow BH 《Disasters》1999,23(1):1-18
Disaster vulnerability is socially constructed, i.e., it arises out of the social and economic circumstances of everyday living. Most often discussed from the perspective of developing nations, this article extends the argument using American demographic trends. Examples from recent disasters, Hurricane Andrew in particular, illustrate how certain categories of people, such as the poor, the elderly, women-headed households and recent residents, are at greater risk throughout the disaster response process. Knowledge of where these groups are concentrated within communities and the general nature of their circumstances is an important step towards effective emergency management. Emergency planners, policy-makers and responding organisations are encouraged to identify and locate high-risk sectors on Community Vulnerability Maps, integrating this information into GIS systems where feasible. Effective disaster management calls for aggressively involving these neighbourhoods and groups at all levels of planning and response, as well as mitigation efforts that address the root causes of vulnerability.  相似文献   
25.
安全生产是构建和谐社会的基础和前提,国有林场的安全应急管理工作直接关系到国有林场的事业发展、经济效益和社会效益,从国有林场的实际出发,提出了一些新思路和新做法.  相似文献   
26.
Farmers from four irrigation districts in Texas and California were questioned about water conservation practices they are now using, those they plan to adopt, and potential incentives that government might offer to induce still further water conservation on their part. While responses differed somewhat from place to place and among individual farmers, the general results were: a) farmers reported that “water conservation” is not new to them, it is something they practice regularly; b) recent innovations such as laser controlled land leveling devices have permitted some substantial water use reductions in recent years; and c) even greater incentive mechanisms that government could provide and that farmers would accept as useful incentives, such as long term low interest loans for water saving equipment, would probably not be able to reduce water use in agriculture much further than 15 percent below current levels. It is recommended nonetheless that Federal agencies and local water districts and individuals should nonetheless pursue water conservation training and education programs, demonstrations of conjunctive use and water banking opportunities for water saving, and increased loan programs for installation of water saving equipment.  相似文献   
27.
Book Reviews     
《Disasters》2000,24(2):173-180
Books reviewed:
Thomas Drabek, Disaster-induced Employee Evacuation
Hugh Brammer, Agricultural Disaster Management in Bangladesh
Boris Porfiriev, Disaster Planning and Emergency Management in Russia
Patrick Bracken and Celia Petty, eds, Rethinking the Trauma of War
R. Cohen and F. M. Deng, eds, The Forsaken People: Case Studies of the Internally Displaced
Tom Trier and Lars Funch Hansen, eds, Conflict and Forced Displacement in the Caucasus: Perspectives, Challenges and Responses  相似文献   
28.
Abstract

A secondary analysis of the British National Travel Survey for the years 2002–2010 shows that the composition of the group of carless households is a good indicator of the level of car dependence in a local area: indeed, while non-car ownership in peripheral and rural areas very often correspond to a marginal socio-demographic situation, this is less and less true as one moves towards larger urban areas. Similarly, while in sparse areas most households without cars are either virtually immobile or reliant on car lifts, in large urban areas the ‘mobility gap’ between car-owning and carless households is considerably smaller, as the latter are able to use modal alternatives to the car. These findings are interpreted with reference to an integrated theoretical framework, showing how changes in land use and the environmental and social impacts of increasing motorization are intimately linked. Notably, the consequences of the self-reinforcing cycle of car dependence on two forms of car-related transport disadvantage (car deprivation and forced car ownership) are highlighted. Overall, the article highlights how the socio-demographic composition and the travel behaviour of carless households vary systematically across different types of area: this has interesting implications for sustainable transport policy and research.  相似文献   
29.
The question of the imperatives induced by the Gandhian concept of non-violence towards animals is an issue that has been neglected by specialists on the thinking of the Mahatma. The aim of this article is to highlight the systematic – and significant – character of this particular aspect of his views on non-violence. The first part introduces the theoretical foundations of the duty of non-violence towards animals in general. Gandhi's critical interpretation of cow-protection, advocated by Hinduism, leads to a general reflection on the duty of non-violence towards animals, the cow being transformed into the representative of all “dumb creation.” The approach adopted by Gandhi to solving the problem of cow-protection focuses on its practical dimensions and is based primarily on reforming animal husbandry. What limits should be imposed on the exploitation of farm animals within the framework of non-violence? Gandhi devoted nearly 30 years to elaborating an animal husbandry system that would be both economically viable and in conformity with the universal ethical principles he drew from religions (especially Hinduism). The interdiction to kill is absolute, since Gandhi not only rejects the breeding of farm animals for the purposes of butchery but also the slaughtering of animals that are no longer capable of providing the services required of them. He therefore concentrated his efforts on drawing up a scheme to reorganize this activity on a national scale while taking into consideration these constraints, which are less contradictory than they may seem to be at first sight. Reviewing the age-old activity of animal husbandry in the light of non-violence is clearly based on the specific nature of Hindu traditions. However, it goes far beyond cultural or religious relativism, since it is also founded on universal ethical principles.  相似文献   
30.
重大工业危险源(罐区)监控预警系统   总被引:4,自引:2,他引:2  
系统建立了管理软件和硬件监控相结合的安全生产监控预警系统,在安全管理的基 础上,把罐区诸多的危险参数给予实时监测、报警和控制。本系统实现了生产过程控制与安全监控 相结合,安全监测报警与事故预案相结合,既满足了生产控制又实现了动态的安全管理,对安全生产 具有较大意义。  相似文献   
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