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991.
Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management
of forest ecosystems. This study analyzed spatial and temporal changes in land use and land cover patterns in a typical mountain
watershed in the Gumushane district along the Northeastern part of Turkey. The area is investigated by comparing LANDSAT images
from 1987 to 2000 and evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of
forest cover type maps from 1971 and 1987 using GIS and FRAGSTATS™.
The results show a general decreasing trend in area of natural land cover types including broadleaf and conifer forests as
well as coppice between 1971 and 1987 (0.54%, respectively). In contrast, between 1987 and 2000 this natural land cover types
show increasing trend (1.6%). In parallel with forest dynamics, the area of managed land including lowland and upland agricultural
areas, rangelands and grasslands increased during the first period and decreased during second period. In terms of spatial
configuration, Gümüşhane forests aren’t generally fragmented by intensive forest utilization in the latter periods. This is
partially due to out-migration of rural population in Gümüşhane. Nevertheless, land use pattern significantly changed over
time depending on a few factors such as unregulated management actions, social pressure and demographic movements. The study
revealed that demographic movements have a major effect on landscape dynamics. 相似文献
992.
全新型生态工业园区的工业共生链网结构研究--新疆石河子国家生态工业(造纸)园区的设计分析 总被引:11,自引:0,他引:11
本文以新疆石河子国家生态工业(造纸)园区的设计为例.运用产业生态学理论,深入系统地分析了生态工业园区的系统构成、工业共生关系以及生态工业链网结构.为全新型生态工业园区的设计及其运行提出了切实可行的建议。 相似文献
993.
过程工业计算机辅助安全防护层分析技术进展 总被引:6,自引:2,他引:4
介绍当前过程工业安全防护层分析(LOPA)的基本内容,研讨LOPA方法与深层次的危险和可操作性分析方法(HAZOP)之间的关系以及计算机辅助HAZOP的研究进展。针对人工LOPA方法的缺点,开发了SDG-HAZOP软件平台,为计算机辅助LOPA平台研发创造了先决条件。应用计算机辅助LOPA方法,使防护层的设置具有更好的针对性、合理性和有效性,发挥对事故的预防和预警作用,并具有良好的发展前景。 相似文献
994.
化学工业园区重大事故场外应急预案编制技术研究 总被引:1,自引:0,他引:1
阐述化学工业园区重大事故场外应急预案编制的技术路线;把编制过程分为调查评估、制度设计、预案编写3阶段,其中调查评估是基础,制度设计是关键;指出危险源辨识、脆弱性分析、应急资源评估、应急组织架构及其职责确定、应急救援运行机制设计等是化学工业园区重大事故场外应急预案编制的工作要点;提出"基本预案+应急功能程序+支持附件"的化学工业园区重大事故场外应急预案结构模式。该编制技术对促进化学工业园区重大事故场外应急预案的科学化、规范化和可操作性具有指导意义。 相似文献
995.
科学构建化工园区安全生产长效机制的关键要素 总被引:1,自引:1,他引:0
针对我国化工园区的发展现状和存在的问题,结合本质安全等现代先进安全管理理念,系统地分析了强化化工园区安全生产长效机制关键要素的手段和措施,为提高化工园区和相关行业的安全管理现状提供了科学依据。指出当前强化园区总体规划和布局论证以及严格执行园区准入制度的重要性;阐明建设项目本质安全化是重要关键所在,应通过在项目构建的不同阶段,分步实施本质安全化设计策略;考虑到园区重大事故多米诺效应概率显著增加,理论研究确定了爆炸和火灾触发多米诺效应的概率和临界距离;特别强调重大危险源的控制和管理是核心问题,提出了园区重大危险源的三级安全管理模式和园区应急资源评估模式。 相似文献
996.
Travis Wagner Samantha Langley-Turnbaugh 《Journal of Environmental Planning and Management》2008,51(4):525-541
While the presence of lead in urban soils from residential lead paint and leaded gasoline is well documented, the relative contribution of lead from area historical industrial activities is not. This study examined the connection between historical industrial sources of lead in Portland, Maine, USA from 1860 to 1970 to current, spatial distributions of soil lead. Collecting 1859 surface and 122 sub-surface soil samples in accordance with USEPA's Lead Safe Yard Protocols, lead concentrations varied from 9 mg/kg to >100,000 mg/kg with most of the samples greater than USEPA's critical value for lead (400 mg/kg). Using historical documents, probable sources of lead were mapped. In comparing two datasets, no clear relationship emerged. Findings were hampered by inability to sample under large areas of impervious surfaces and private properties. Because of lead's immobility in soil, one would expect decreasing concentration with depth, but lead concentrations varied with depth and location. The haphazard dumping of lead-contaminated industrial waste and the relocation of contaminated fill are likely factors. These findings suggest that in urban areas where multiple historical sources of lead existed, surface sampling to determine presence of lead may not be sufficient to protect public health. 相似文献
997.
Heavy metal removal and cyanide destruction in the metal plating industry: an integrated approach from egypt 总被引:1,自引:0,他引:1
Wastewater produced from a metal plating is a major environmental problem. Industrial auditing revealed that the main source
of pollution mainly originated from rinsing water. The characterization of final effluent showed that it is highly contaminated
with hazardous heavy metals and cyanide. The concentration of copper, hexavalent chromium, nickel, and cyanide in the rinsing
water of metal plating department was 14.8, 40.9, 13.3, and 19 mg/l, respectively. The concentration of cyanide and zinc from
the galvanizing department reached 60 and 80 mg/l. The remediation scheme included the application of in-plant control measures
via changing the rinsing process followed by the destruction of cyanide and reduction of hexavalent chromium bearing wastes.
The pretreated wastes were then mixed with other industrial wastes prior to a combined chemical coagulation-sedimentation
using lime and/or lime in combination with ferric chloride. The results indicated that, after applying the waste minimization
measures alone at the source, prior to final treatment of industrial waste, removal rates of cyanide, copper, nickel, and
chromium concentrations were 23.2%, 14.9%, 32.3%, and 55.3%, respectively in the rinse water from metal plating department.
Furthermore, the removal rates of cyanide and zinc in the galvanizing department reached 59.7% and 24.3. The integrated control
measures and treatment scheme led to more than 99% removal of copper, nickel, chromium, and zinc, while the complete removal
of cyanide was achieved in the final effluent. 相似文献
998.
Field Validation of a Conservation Network on the Eastern Shore of Maryland,USA, Using Breeding Birds as Bio-Indicators 总被引:1,自引:0,他引:1
Maryland’s Green Infrastructure (GI) is a network of large, intact natural areas (hubs), interconnected by linear swaths of
riparian or upland vegetation (corridors). The GI serves significant ecological functions and provides the bulk of the state’s
natural support system. This study examined whether the GI as mapped does, in fact, identify Maryland’s most ecologically
valuable forested lands, using forest interior dwelling birds (hereafter called “forest birds”) as bio-indicators. We conducted
bird point counts within forest both inside and outside of hubs on Maryland’s Eastern Shore. We also collected a wide variety
of habitat data. We found that both the condition of a forest and its surrounding landscape influenced the bird communities.
On average, forest bird richness was significantly higher within hubs; furthermore, almost all sites with at least five forest
bird species present were in hubs. Forest bird richness and abundance were highest in undisturbed, mature broadleaf forest
with wetlands and streams nearby. We detected a significant relationship between forest bird richness and the ecological score
of a finer-scale landscape assessment, focused on “cells” of about 0.1 ha in size. This field study also validated the Rapid
Field Assessment (RFA) protocol developed in 2001 to assess, on the ground, the relative condition of individual sites or
properties within the GI. Forest bird richness and abundance were positively correlated with the RFA community scores. Our
results underscore the importance of maintaining regional biological diversity by retaining large blocks of forest, especially
mature forest containing streams and wetlands. 相似文献
999.
Conservation-based development programs have sought to create economic opportunities for people negatively impacted by biological diversity protection. The USDA Forest Service, for example, developed policies and programs to create contracting opportunities for local communities to restore public lands to replace jobs lost from reduced timber harvest. This article examines 12 years of Forest Service land management contracting in western Oregon, Washington, and northern California to evaluate if contractors located in communities near national forests have been awarded more land management contracts and contract value over time. We find that land management contracting spending has declined dramatically and, once we control for intervening factors, we find that local contractors have received a smaller proportion of land management contracts over time. 相似文献
1000.
This paper explains briefly the conceptual framework of an ecosystem-based multiple-use forest management planning focusing on biodiversity conservation and participation. Some results from a case study were documented to realize the implementation of the concept. A strong liaison between the related institutions and major stakeholders and the effective use of Geographic Information System (GIS) and Remote Sensing (RS) are necessary. Effective participation is evident only with the involvement of enthusiastic and skillful stakeholders. A case study of ??neada, Turkey, supported the idea that participation as communication has better possibilities to promote multiple-use forest management than participation as information gathering. Primary challenges relate to the effectiveness of conservation program, availability of coherent biodiversity data, capacity building; awareness, training, and common understanding of biodiversity and protected area concept; coordination among the related institutions and stakeholders; and willingness and enthusiasm of authorities to accept and implement the concept. 相似文献