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391.
The conscientious and planned integration of frontier areas into the national economy can at least partially alleviate both environmental and economic problems that are common to many developing countries. Full development of the agricultural potential of frontier areas can lessen the environmental deterioration often found in traditionally settled regions. Exploitation of mineral resources, in particular energy resources, can lessen economic burdens associated with increased costs of imported energy. The authors examine how recent international developments have spurred the government of Guatemala to undertake measures designed to develop a previously underutilized region. The short term negative consequences of increased costs for imported grains and petroleum may well have a positive result in the long term insofar as they lead to more balanced and rational use of land and resources. 相似文献
392.
Involuntary eye movements in salamanders 总被引:1,自引:0,他引:1
393.
To some degree it is unfair to evaluate a post-disaster housing program as to its effectiveness in decreasing vulnerability and preventing future disasters. As Burton states, "With rare exceptions, administrators and techniques have been trained to cope with disaster rather than to prevent it" [reference (2), p.197]. These were certainly not goals articulated by the agency responsible for constructing housing after Fifi. However, the authors feel that failure to evaluate specific projects by persons knowledgeable of the projects functioning, will only forestall the shift which Cuny calls for, "… from disaster response to disaster mitigation and prevention" [reference (4), p.123). In doing this we hope to add some specific case study data to the growing literature on disaster mitigation and prevention. Disaster vulnerability in Honduras is overwhelmingly related to flooding. More crucial than the materials and construction of housing is the issue of siting. If appropriately sited, houses made of bajarique, wood, or concrete block are able to withstand the heavy rains associated with a hurricane. Regarding the siting of the projects, the Honduras Project clearly has one positive and one negative accomplishment in the cases of Santa Rica and Flores, respectively. San Jose is less clear but is certainly a much safer site than those formerly occupied by the residents, in that there is no danger of flooding. The present site was not flooded during Fifi nor did it experience mudslides. However, the future is not so clear regarding the latter. Within the village proper a large amount of vegetation has been added which will tend to stabilise the soil on the steeper slopes. The streets, however, are seriously eroded and probably can not be maintained for vehicle usage, which does not pose a serious problem to the residents as none possess automobiles or trucks. One large gully bisects the village and receives run-off from the adjacent hills. It has been expanding, which would suggest that the slopes above the village could prove problematic in case of a Fifi-sized storm. Flores is located on a very poor site in reference to prevention and mitigation. It is located in a portion of the Sula Valley which is prone to flooding and, as mentioned before, was inundated by over 2m of water during hurricane Fifi. No prevention techniques were possible by NAEA/HEA and the houses were built on earthen mounds barely adequate to keep water out during the rainy season. The nearby dike which could possibly provide protection is non-functional due to poor maintainance. Given a storm of Fifi's magnitude, or possibly smaller, this site will again be flooded. Santa Rica is clearly well sited concerning flooding: it did not experience flooding during Fifi and is not flood prone. However, houses did experience some wall damage due to earthquakes following and associated with the Guatemalan quake of 1976. Due to the size and nature of the latter much "re-adjustment" occurred in the neighbouring fault system; however, damage to the houses was all superficial. We feel the residents were vocal about their concern due to the severity of the Guatemalan disaster and their lack of experience with concrete block houses. That the two sites (particularly Flores and partially San Jose) are vulnerable to future disasters cannot be considered solely the fault of an outside agency without local knowledge and understanding. In the engineering report issued during the construction it was explicitly stated that in Flores, "Future flooding remains a danger," [reference (6), p.49]. The future residents of Flores had gained access to the land from the National Agrarian Institute and were anxious to receive assistance in building homes. In fact, CARE, which had previously given these people tin roofing for houses, was threatening to take it back since the people had not yet started building. NAEA/HEA were responding to people in a rather desperate situation. But, on the other hand, they were responding to people who had been promised (not given) land by an agency of the Honduran national government which would be cognizant of the potential flooding at this site. Likewise, in San Jose, where mudslides and erosion remain a threat, the land was provided by a local government agency, the municipality. Although our goal in this discussion has not been to establish blame, we feel it imperative to mention the sequence of events that resulted in the questionable siting of Flores and San Jose. It is very easy and often accurate to place blame on outsiders who lack sophistication and knowledge about such matters. In this case local input did not result in post-disaster planning that is actually precautionary. This, we feel, illustrates the extreme complexity of cross-cultural aid, especially in the post-disaster period. It also points to the need for precautionary planning with reference to permanent post-disaster reconstruction. 相似文献
394.
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397.
William Lin Robert L Spore Edmund A Nephew 《Journal of Environmental Economics and Management》1976,3(3):236-252
This study quantifies the short-run impacts of reclamation on strip mining costs, coal prices, production, and employment in Appalachia. A process analysis model is developed and used to estimate short-run strip-mined coal supply functions under conditions of alternative reclamation requirements. Then, an econometric model is developed and used to estimate coal demand relations. Our results show that full reclamation has rather minor impacts. In 1972, full reclamation would have increased strip-mined coal production costs an average of $0.35 per ton, reduced strip-mined coal production by 10 million tons, and cost approximately 1600 jobs in Appalachia. 相似文献
398.
399.
James R Payne John R Clayton Jr. Bruce E Kirstein 《Spill Science & Technology Bulletin》2003,8(2):201-221
The interactions of physically dispersed oil droplets with suspended particulate material (SPM) can be important for the transport of bulk quantities of spilled crude oil and polycyclic aromatic hydrocarbons (PAH) to subtidal sediments. The literature regarding oil/SPM interactions is reviewed, and results from whole-oil droplet/SPM interaction kinetics and pure-component (Prudhoe Bay crude oil distillate cut) equilibrium partitioning experiments are presented. The effects of oil type, SPM characteristics, and salinity on the interaction rates are examined, and the importance of whole-oil droplet/SPM interactions on particle agglomeration and settling behavior are discussed. Whole-oil droplet/SPM interactions are retarded as oil droplet dispersion into the water column is inhibited by oil viscosity increases due to evaporation weathering and water-in-oil emulsification. Compared to whole oil droplet/SPM interactions, dissolved-component/SPM adsorption is not as significant for transport of individual components to sediments. The information presented in this paper can be used to augment computer-based models designed to predict oil-spill trajectories, oil-weathering behavior, and spilled oil impacts to the marine environment. 相似文献
400.
V. Krishna Prasad K.V.S. Badarinath H. Tsuruta S. Sudo S. Yonemura John Cardina Benjamin Stinner Richard Moore Deborah Stinner Casey Hoy 《The Environmentalist》2003,23(2):175-187
Forests and soils are a major sink of carbon, and land use changes can affect the magnitude of above ground and below ground carbon stores and the net flux of carbon between the land and the atmosphere. Studies on methods for examining the future consequences of changes in patterns of land use change and carbon flux gains importance, as they provide different options for CO2 mitigation strategies. In this study, a simulation approach combining Markov chain processes and carbon pools for forests and soils has been implemented to study the carbon flows over a period of time. Markov chains have been computed by converting the land use change and forestry data of India from 1997 to 1999 into a matrix of conditional probabilities reflecting the changes from one class at time t to another class time t+1. Results from Markov modeling suggested Indian forests as a potential sink for 0.94 Gt carbon, with an increase in dense forest area of about 75.93 Mha and decrease of about 3.4 Mha and 5.0 Mha in open and scrub forests, if similar land use changes that occurred during 1997–1999 would continue. The limiting probabilities suggested 34.27 percent as dense forest, 6.90 as open forest, 0.4 percent mangrove forest, 0.1 percent scrub and 58 percent as non-forest area. Although Indian forests are found to be a potential carbon sink, analysis of results from transition probabilities for different years till 2050 suggests that, the forests will continue to be a source of about 20.59 MtC to the atmosphere. The implications of these results in the context of increasing anthropogenic pressure on open and scrub forests and their contribution to carbon source from land use change and forestry sector are discussed. Some of the mitigation aspects to reduce greenhouse gas emissions from land use change and forestry sector in India are also reviewed in the study. 相似文献