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91.
The fate of waste in Hawaii: Technology assessment and solid waste planning in Hawaii, 1968–78
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Jordan P. Howell 《Singapore journal of tropical geography》2015,36(1):67-82
In this article I consider the initial period of solid waste management planning in the US state of Hawaii. The State encountered a number of economic and ecological controversies during its solid waste management planning, a process that was prompted by the US Environmental Protection Agency. Some issues, like project financing, were common across the US, while others, such as the potential of waste materials to reduce reliance on imported food and materials, were more unique to Hawaii. The controversies from this initial planning period were never quite fully resolved; as they lingered, they were interpreted differently across the Islands. Based on a close reading of government, advocacy group, waste industry and news media documents, I examine the controversies over solid waste management of the time and consider how the ‘dual nature’ of waste in Hawaii—simultaneously an ecological threat and (potential) economic input—shaped the adoption of solid waste management systems there. This article adds to an expanding literature examining infrastructure in environmental and technology histories. 相似文献
92.
Immediately following the May 2011 tornado, the city of Joplin, Missouri, initiated recovery efforts to rebuild the part of the community devastated by this event. In doing so, city officials introduced two new safety measures and recommended several others. The main objective of this paper is to explore the tornado survivors' compliance with the safety features recommended by the Joplin city authorities. Face‐to‐face interviews, as well as other methods, were used to survey respondents who were living within the tornado path (damage zones) at the time of the tornado. Results showed that 43 percent of all respondents implemented at least one recommended tornado measure in rebuild or repair their destroyed/damaged homes. Further, it was found that three variables considered here— rebuild or repair, damage zone category, and perceived tornado risk—were all significant contributors to a homeowner's decision to implement recommended tornado safety measures. The paper concludes with a recommendation for expanding tornado safety education among the respondents. 相似文献
93.
Paul A. Knapp 《The Professional geographer》1991,43(4):486-499
Five semiarid Montana ghost towns abandoned for more than 45 years were studied to understand better the nature of soil and vegetation recovery following severe human impacts. Discriminant analysis was used to interpret and classify variation among land-use intensity groups. Recovery at the five towns was strongly linked to the degree of the initial soil disturbance, vegetation type, and precipitation. Recovery of the vegetation to ambient conditions was far from complete in all but one town. 相似文献
94.
The most important copper minerals of the Las Cruces deposit in the pyrite belt of southern Spain are supergene enrichment zone sulphides of which chalcocite is the most significant. The deposit is overlain by 140 metres of barren marls and has been explored only by drilling. Drill cores have been split and assayed, but it became clear that there was a substantial problem related to core recovery which affects, in particular, some of the higher grade material. Much of the chalcocite is present in a friable and unconsolidated form and its progressive loss is evident visually in many core samples. The result of this loss of chalcocite is that there is a systematic downward bias on copper assays, leading directly to under-reporting of the copper resource. Studies of the assay data indicate the likely degree of under-reporting, but there is no simple way in which the reported resource estimates can validly be corrected. 相似文献
95.
解决数据本地集中带来的风险,是测绘资料管理部门面临的重要问题。本文通过对容灾关键技术的研究和对测绘数字成果特点的分析,给出了基于远程容灾技术,建立测绘数字成果异地远程容灾体系的思路。 相似文献
96.
MATTHEW C. LaFEVOR 《Geographical review》2012,102(2):202-224
The discovery, extraction, and monopolistic control of key natural resources was a priority of New Spain's colonial administration. Managing the region's abundant resources, however, often proved difficult for the Spanish Crown. Human and environmental challenges impeded protoindustrial growth and development, and monopolistic control of resources often met resistance. In this article I examine these processes in the context of New Spain's little‐known monopoly on sulphur—a yellow, powdery mineral the Crown jealously guarded as its own. Sulphur was critical for gunpowder and explosives production, yet the Crown often failed to produce enough of it to meet the growing demand by its military and the silver blast‐mining industry. Colonial documents reveal administrators’ attempts to improve sulphur production through reform measures, which included advising sulphur miners on how to discover sulphur deposits and, eventually, how to develop their mines. Efforts to improve sulphur production were moderately successful, although the process was messy and inefficient. 相似文献
97.
In 1994, a directed fishing moratorium was declared for Grand Bank American plaice (Hippoglossoides platessoides) and yellowtail flounder (Limanda ferruginea) stocks because both stocks showed severe declines in abundance from heavy exploitation during the mid 1980s and early 1990s. Four years later, the fishery for yellowtail re-opened while the plaice stock has shown little recovery and the moratorium is still in effect. To assess the possible causes of the differences in recovery between species, we examined the spatial structure and environmental characteristics of the continental shelf nursery habitats of plaice and yellowtail, and their relationship to recruitment variability and overall population size. Depth plays a major influential role determining the spatial pattern and the abundance of juveniles of both species and in the case of plaice the spatial structure of the adult population also determines the amount of nursery area utilised by juveniles. Recruitment variability was higher in plaice than in yellowtail. We found year class synchrony in both species indicating that common environmental conditions and/or biological processes are affecting recruitment in a similar manner. Density-dependent regulation appears to be more severe in yellowtail and this should contribute to a more stable population when compared to plaice. These results are discussed in terms of resiliency of both stocks to over-exploitation. 相似文献
98.
正新疆北部石炭系发育一套巨厚的混杂有火山物质的烃源岩。有机质丰度以及类型等指标显示具有作为烃源岩的潜力。笔者综合运用薄片等分析资料将其划分为凝灰岩、沉凝灰岩、凝灰质泥岩、含碳质泥岩,并分类研究了其地球化学特征。针对富火山物质烃源岩成熟度高、有机质丰度低的特点,首次运用生烃模拟实验结合数值模拟开展其有机碳含量恢复,建立了不同火山物质含量烃源岩有机 相似文献
99.
P. Yunus Ali 《Marine Geodesy》2013,36(1):26-39
The tsunami waves generated during the Sumatra-Andaman earthquake of 26 December 2004 devastated the coastal area along Trinkat Island, causing sudden changes to the morphology of the landforms. This study uses a series of satellite images to record the short-term morphological response and shoreline changes as well as the recovery of coastal land after its destruction. Results indicate that the island experienced substantial erosion and a significant reduction in land area. Shoreline erosion is more prevalent than accretion at an average linear regression rate of ~?9 m per year between 2004 and 2013. The major morphological changes at Trinkat Island were observed in coastal inlets, beaches, and bay head-lands. Straight beaches had almost recovered eight years after the tsunami; however, erosion is continually observed in other areas. Our study will help understanding the response and recovery of shorelines in Indian Ocean regions after the 2004 tsunami. 相似文献
100.
Yin Long Tianming Huang Fen Zhang Zhenbin Li Baoqiang Ma Yiman Li Zhonghe Pang 《水文研究》2021,35(4):e14166
The use of the sulphate mass balance (SMB) between precipitation and soil water as a supplementary method to estimate the diffuse recharge rate assumes that the sulphate in soil water originated entirely from atmospheric deposition; however, the origin of sulphate in soil and groundwater is often unclear, especially in loess aquifers. This study analysed the sulphur (δ34S-SO4) and oxygen (δ18O-SO4) isotopes of sulphate in precipitation, water-extractable soil water, and shallow groundwater samples and used these data along with hydrochemical data to determine the sources of sulphate in the thick unsaturated zone and groundwater of a loess aquifer. The results suggest that sulphate in groundwater mainly originated from old precipitation. When precipitation percolates through the unsaturated zone to recharge groundwater, sulphates were rarely dissolved due to the formation of CaCO3 film on the surface of sulphate minerals. The water-extractable sulphate in the deep unsaturated zone (>10 m) was mainly derived from the dissolution of evaporite minerals and there was no oxidation of sulphide minerals during the extraction of soil water by elutriating soil samples with deionized water. The water-extractable concentration of SO4 was not representative of the actual SO4 concentration in mobile soil water. Therefore, the recharge rate cannot be estimated by the SMB method using the water-extractable concentration of SO4 in the loess areas. This study is important for identifying sulphate sources and clarifying the proper method for estimating the recharge rate in loess aquifers. 相似文献