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201.
浅析辽河流域水环境管理现状及改善措施 总被引:1,自引:0,他引:1
辽河流域是我国北方重要的河流型流域,水环境污染问题突出。文章从水环境管理体制、水污染控制方式、水生态安全管理、预警监控4个方面剖析了辽河流域水环境管理现状,并提出针对性的改善措施,对促进辽河流域水环境管理能力提高具有积极的实际意义。 相似文献
202.
化工园企业环境风险分级评估与管理方法研究 总被引:1,自引:1,他引:0
为减少环境污染事故的发生,文章从化工园内企业化学品储存、运输、生产等潜在风险环节出发,结合企业风险管理水平及周边受体易损性,利用环境风险综合评价指数法对企业环境风险进行分级评估。在此基础上,以长江下游某化工园区调研的41家企业作为案例进行评估,结果显示:园区内重大、较大、一般环境风险企业分别占调查总数的2.4%,65.9%,31.7%。该评估方法从化工园企业风险控制的实际需求出发,具有实用性和可操作性,为化工园更有效的风险管理提供技术支持。 相似文献
203.
近年来,水文部门根据降水预报,探索流域洪水模拟预报,对密切监视暴雨洪水、做好防汛调度决策起到良好作用。文章在统计分析小凌河多年暴雨洪水的基础上,采用不同雨级平均24 h时段比率,进行凌河保护区洪水模拟预报成果编制研究。构建"以流域为单元、以干流为主线、以水库和河道水文站为控制节点"的流域河库联合模拟预报调度成果图表,实现流域水系河库模拟预报调度。通过科学的实时洪水调度可以调蓄洪水,减轻洪水灾害。同时,也可为流域洪水资源化提供保障和科学依据,实现流域的综合管理。 相似文献
204.
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206.
从环境监测与环境影响评价内容以及职能入手分析,研究二者之间的关系,并对环境监测中存在的问题与建议,进行重点分析,希望能够为今后环境监测与环境影响评价工作起到重要的借鉴作用。 相似文献
207.
Archaeological and paleontological datasets are used in conservation to add time-depth to ecology. In central Texas, several
top carnivores including prehistoric Native American hunters have been extirpated or have had their historic ranges restricted,
which has resulted in pest-level white-tailed deer (Odocoileus virginianus texana) populations in some areas. Differences in body size of deer between prehistory and modernity are expected, given that a
lack of predation likely has increased intraspecific competition for forage among deer, resulting in smaller body size today.
In fact, modern deer from settings without harvest pressure are significantly smaller than those from harvested areas and
from prehistoric deer. From a natural history perspective, this research highlights potential evolutionary causes and effects
of top-predator removal on deer populations and related components of biological communities in central Texas. 相似文献
208.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294
Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial
Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource
Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on
Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental
management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation
of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used
with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products
to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for
the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being
promoted by UNIDO′s Cleaner Production Programme.
Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of
chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the
effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing
approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more
service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration
project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which
is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved
through the development of company specific business models that implement the above-indicated Chemical Leasing concept with
the support from the Mexican National Cleaner Production Centre (NCPC).
Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing
sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial
sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project,
several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners.
The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies
in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international
level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach
to International Chemicals Management (SAICM) Preparation Conference in Vienna.
Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level,
UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical
leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical
Leasing projects and work programmes. 相似文献
209.
Ornamental Plants as Invasive Aliens: Problems and Solutions in Kruger National Park,South Africa 总被引:1,自引:0,他引:1
The most widespread invasive alien plant species in South Africa’s Kruger National Park (KNP) were either introduced unintentionally
along rivers and roads, or intentionally for use as ornamentals. We examine the spatial distribution of ornamental alien plants
in KNP, look at the link between human population size, history, and species richness, and show how the distribution of particular
species reflects the likely history of ornamental plantings. Results are used to assess whether past management actions have
been appropriately directed.
Two hundred and fifty-eight alien species have been recorded in the 36 tourist camps and staff villages. The number of staff
housed in villages explains much of the diversity of cultivated alien plant species. Older camps also tend to have more ornamental
alien plant species. However, the lack of a strong link between camp age and number of cultivated species suggests that ornamental
plants have been widely spread around the KNP by humans. We also show that increased camp activity (either size or age) has
led to more ornamental species, while, with the notable exception of Skukuza, camp activity has had a much smaller effect
on the number of noncultivated species. Noncultivated species tend to be naturally dispersed, as opposed to directly spread
by humans between camps.
Past management prioritized certain species on the basis of their potential to invade KNP and on the prevailing national legislation.
These species were removed manually and follow-up control was carried out. Once the priority species were deemed to be under
control, less invasive species were targeted. All alien species were removed from vacated houses, regardless of the potential
invasiveness of the species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
210.
Human alteration of the landscape has an extensive influence on the biogeochemical processes that drive oxygen cycling in streams. We estimated trends from the mid-1990s to 2003, using the seasonal Mann-Kendall's test, for percent saturation dissolved oxygen (DO), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and ammonia-nitrogen (NH(3)-N) for 12 sites in the Rock Creek watershed, northwest Oregon, USA. In order to understand the influence of landscape change, scale, and stormwater runoff management on dissolved oxygen trends, we calculated land cover change through aerial photo interpretation at full-basin, local (near sample point) basin, and 100m stream buffer scales, for the years 1994 and 2000. Significant (p < or = 0.05) trends occurred in DO (increasing at five sites), COD (decreasing at seven sites), TKN (decreasing at five sites, increasing at one site), and NH(3)-N (decreasing at one site, increasing at one site). Significant land cover change occurred in agricultural land cover (-8% for the entire basin area) and residential land cover (+10% for the entire basin area) (p < or = 0.05). Correlation results indicated that: (1) forest cover negatively influenced COD at the full basin scale and positively influences NH(3)-N at local scales, (2) residential land cover influenced oxygen demand variables at local scales, (3) agricultural land cover did not influence oxygen demand, (4) local topography negatively influenced TKN and NH(3)-N, and (5) stormwater runoff management infrastructure correlated positively with COD at the local scale. This study indicates that landscape factors influencing DO conditions for the study streams act at multiple scales, suggesting that better knowledge of scale-process interactions can guide watershed managers' decision making in order to maintain improving water quality conditions. 相似文献