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91.
I. Lorenzoni A. Jordan D. Favis-Mortlock D. Viner J. Hall 《Regional Environmental Change》2001,2(3):106-117
The weight of scientific evidence suggests that human activities are noticeably influencing the world's climate. However,
the effects of global climate change will be unevenly spread, due to local variations in vulnerability and adaptive capacity.
Using downscaled projections of future UK climates over the next 50 years, this paper investigates the impacts of, and possible
responses to, climate change in one small area in eastern England, selected as a test-bed for sustainable agriculture. It
shows that local agricultural systems are vulnerable to changes in the climate. At present, however, these considerations
have a limited effect on agricultural operations, which are mainly driven by short-term events and 'non-climate' policies,
such as agricultural price support. The capacity of agricultural systems to adapt successfully to climate change will be determined
by the ability of producers to integrate climate change into their planning strategies with a view to ultimately ensuring
sustainable agricultural practices in the long term.
Electronic Publication 相似文献
92.
Accidents involving contractors continue to occur with regular frequency. By using the standard set within the PSM 29 CFR 1910.119(h) regulations, it has been identified that certain aspects of the way contractors do work are not up to the stipulated regulatory requirements especially regarding matters like not providing mandatory personal protective equipment (PPE) to the workers, not discussing hazards related to handling procedures with the workforce and improper control of non-routine activities during changes in shifts. The PSM 29 CFR 1910.119(h) regulations promulgated in 1992 provides standards that covered processes to obtain and evaluate data regarding contractors' health and safety programs as well as the contractors' performance evaluation. Many of the accidents involving contractors are direct result of poor training of contractors and/or poor control of the contracted work. Even though most organizations have their own contractor management systems, there are issues in meeting the requirements of PSM. The PSM standard only state “what to do” not “how to do it”. This is known as self-regulatory policy which depends on the industries understanding to interpret the standard that also contribute to this problem. This paper presents a structured and easy technique to plan and implement a practical and comprehensive contractors' management system in process industries that will comply with OSHA CFR 1910.119. A model has been developed based on this technique and its application has been tested in a pilot plant for compliance to PSM regulation. The model is beneficial to the process industries as any deficiencies in the PSM contractors' management program will be highlighted by the model which will then easily correct the identified deficiency so as to minimize and prevent catastrophic accidents. 相似文献
93.
94.
Anna‐Katharina Hornidge Lisa Oberkircher Bernhard Tischbein Gunther Schorcht Anik Bhaduri Ahmad M. Manschadi 《Natural resources forum》2011,35(4):251-268
The Khorezm region is located in the northwest of Uzbekistan, approximately 350 km from the current shore of the Aral Sea. It comprises a large‐scale irrigation system that conveys water from the river Amu Darya to agricultural land cropped mainly with cotton, wheat, and rice. Khorezm's water resources are vulnerable as they depend on upstream developments and are indispensable to rural livelihoods and state budgets. Since water scarcity is expected to increase in the future, sustainable water management is a necessity. Hence, the objectives of the paper are to: (1) conceptualize the distinctive features of water management in Khorezm; (2) provide an integrated analysis of water management by establishing linkages between society, technical infrastructure, and the bio‐physical environment; and (3) make policy and technology recommendations for improved water management. To conceptualize water management in Khorezm, the paper distinguishes three types of practices: formal practices, strategic practices, and discursive practices. Based on these, it presents an analysis of water management on the state water management level, the water user association level, and the farmer and field level. For each level, recommendations are given. The paper concludes that elements of integrated water resources management (IWRM) such as transparency, accountability, participation, and technical efficiency are relevant to improve water management in Khorezm, as elsewhere. In addition, it underlines the need to create legal space for agency and innovation. Technical tools such as models are increasingly important for facilitating transparency and enabling agents to access and make use of information across the management hierarchy. 相似文献
95.
The prevalence of forestry practices such as thinning and pruning have gradually decreased since the 1980s. Researchers have noted an increased flood risk with decreased forestry practices for coniferous plantations in Japan on the basis of infiltration and overland flow measurements at a plot scale (typically several square meters). However, no studies have examined changes in peak flow with decreased forestry practices at a watershed scale (typically several tens or hundreds of square kilometers) even though flood disasters generally occur at this scale in Japan. We examined changes in frequency distributions of daily precipitation (P) and runoff (Q) during the period 1979-2007 at the Terauchi watershed, where forestry practices are known to have decreased. For this purpose, we divided P and Q data into 14 and 15 classes according to the magnitude, respectively, and examined changes in the frequency for each class during the period. We observed no significant increasing trend for any P or Q class. Even when taking into account the effect of interannual variations in precipitation on the frequency for each Q class, there was no significant increasing trend in the frequencies except for two Q classes with moderate Q values. These results suggest that the increase in flood risk due to decreased forestry practices might be less than expected. 相似文献
96.
Vassilios A. Tsihrintzis Hector R. Fuentes Rao K Gadipudi 《Journal of the American Water Resources Association》1996,32(2):317-331
ABSTRACT: Agricultural and urban activities in the West Wellfield Interim Protection Area (WWIPA), located in West Dade County in South Florida, have the potential to impact both the environmentally sensitive Everglades and the Biscayne Aquifer. The Hydrological Simulation Program-FORTRAN (HSPF) is used to simulate surface runoff, ground water recharge, and transport of sediments, nutrients, and pesticides in the WWIPA, as a basis to quantify impacts and evaluate alternatives. Presented are four model test runs that consider current conditions, the effect of future urbanization of the agricultural land, as well as two preventive actions to minimize pollution levels. Preventive actions include application of minimum required rates of fertilizers and replacement of fertilizers by sewage sludge. Model results show that under current practices, sediments, nutrients, and pesticides are present in surface runoff and nutrients enter the ground water, and that both urbanization and preventive actions result in pollutant reductions. 相似文献
97.
Christopher A. Ellison Quentin D. Skinner Katta J. Ready 《Journal of the American Water Resources Association》2006,42(1):55-68
Sage Creek in south‐central Wyoming is listed as impaired by the U.S. Environmental Protection Agency (USEPA) due to its sediment contribution to the North Platte River. Despite the magnitude of sediment impacts on streams, little research has been conducted to characterize patterns of sediment transport or to model suspended sediment concentration in many arid western U.S. streams. This study examined the relationship between stream discharge and suspended sediment concentration near the Sage Creek and North Platte River confluence from 1998 through 2003. The objectives were to determine patterns of stream discharge and suspended sediment concentration, produce a sediment prediction model, and compare sediment concentrations for the six‐year period. Stream discharge and suspended sediment transport responded rapidly to convective storms and spring runoff events. During the study period, events exceeding 0.23 m3/s accounted for 92 percent of the sediment load, which is believed to originate from erodible headwater uplands. Further analysis of these data indicates that time series modeling is superior to simple linear regression in predicting sediment concentration. Significant increases in suspended sediment concentration occurred in all years except 2003. This analysis suggests that a six‐year monitoring record was insufficient to factor out impacts from climate, geology, and historical sediment storage. 相似文献
98.
Fobissie B. Kalame Johnson Nkem Monica Idinoba Markku Kanninen 《Mitigation and Adaptation Strategies for Global Change》2009,14(2):135-151
Many studies have suggested various kinds of forest policies, management planning and practices to help forests adapt to climate
change. These recommendations are often generic, based mostly on case studies from temperate countries and rarely from Africa.
We argue that policy and management recommendations aimed at integrating adaptation into national forest policies and practices
in Africa should start with an inventory and careful examination of existing policies and practices in order to understand
the nature and extent of intervention required to influence the adaptation of forest ecosystems to climate change. This paper
aims to contribute to closing this gap in knowledge detrimental to decision making through the review and analysis of current
forest policies and practices in Burkina Faso and Ghana and highlighting elements that have the potential to influence the
adaptation of forest ecosystems to climate change. The analysis revealed that adaptation (and mitigation) are not part of
current forest policies in Burkina Faso and Ghana, but instead policies contain elements of risk management practices which
are also relevant to the adaptation of forest ecosystems. Some of these elements are found in policies on the management of
forest fires, forest genetic resources, non-timber resources, tree regeneration and silvicultural practices. To facilitate
and enhance the management of these elements, a number of recommendations are suggested. Their implementation will require
experienced and well-trained forestry personnel, financial resources, socio-cultural and political dimensions, and the political
will of decision makers to act appropriately by formulating necessary policies and mainstreaming adaptation into forest policy
and management planning. 相似文献
99.
We report on the effects of forest management practices of understory removal and N-fixing species (Cassia alata) addition on soil
CO2 fluxes in an Eucalyptus urophylla plantation (EUp), Acacia crassicarpa plantation (ACp), 10-species-mixed plantation (Tp), and
30-species-mixed plantation (THp) using the static chamber method in southern China. Four forest management treatments, including
(1) understory removal (UR); (2) C. alata addition (CA); (3) understory removal and replacement with C. alata (UR+CA); and (4)
control without any disturbances (CK), were applied in the above four forest plantations with three replications for each treatment.
The results showed that soil CO2 fluxes rates remained at a high level during the rainy season (from April to September), followed by
a rapid decrease after October reaching a minimum in February. Soil CO2 fluxes were significantly higher (P < 0.01) in EUp (132.6
mg/(m2·hr)) and ACp (139.8 mg/(m2·hr)) than in Tp (94.0 mg/(m2·hr)) and THp (102.9 mg/(m2·hr)). Soil CO2 fluxes in UR and CA
were significantly higher (P < 0.01) among the four treatments, with values of 105.7, 120.4, 133.6 and 112.2 mg/(m2·hr) for UR+CA,
UR, CA and CK, respectively. Soil CO2 fluxes were positively correlated with soil temperature (P < 0.01), soil moisture (P < 0.01),
NO3?-N (P < 0.05), and litterfall (P < 0.01), indicating that all these factors might be important controlling variables for soil CO2
fluxes. This study sheds some light on our understanding of soil CO2 flux dynamics in forest plantations under various management
practices. 相似文献
100.
扎兰屯市十分重视环境保护事业的发展,特别是"十一五"期间,环境质量有了突破性改善。环保局以科学发展观为指导思想,认真梳理工作中的经验做法,存在问题。重点在污染减排、环境监管、环保投资、环保意识提高、建设项目管理、维护群众的合法权益等方面与各基层环保交流经验,寻求在突破,积极探索美丽与发展双赢的新道路。 相似文献