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81.
基于GIS的乌梁素海水体富营养化状况的模糊模式识别 总被引:14,自引:7,他引:7
利用基于MATLAB 7.0实现的模糊模式识别交叉迭代模型对2006年5—10月分布于乌梁素海各水体功能区的21个水质监测点的富营养化等级进行了模糊模式识别,并在GIS技术支持下,用Arcview的空间分析功能绘制富营养化等级识别结果、对富营养化状态影响权重最大的评价指标总氮(TN)含量和富营养化状态控制元素总磷(TP)含量对应的富营养化等级水体和地表水质等级水体的空间分布月变化Grid专题图.将富营养化状态变化及其分布区域与乌梁素海同期水质监测指标浓度变化及其分布区域进行对比分析及验证.结果表明,富营养化等级识别结果的时空分布与实际情况相符,能够比较准确地反映富营养化等级定量的时空变化趋势. 相似文献
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83.
环境监测实验室废液的管理与处理方法 总被引:2,自引:0,他引:2
徐根红 《环境监测管理与技术》2007,19(6):50-51
环境监测实验室的废液处理常常被忽视,提出建立有效的废液管理制度的必要性.有针对性地介绍了环境监测实验室中常见废液的处理方法. 相似文献
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86.
我国电子废弃物的处理处置正向产业化方向稳步推进。本文概括了电子废弃物的特点,以及我国目前处理电子废弃物的现状。遵照循环经济理念,并基于我国国情,提出了我国在电子废弃物处理处置过程中应遵循的主要原则和今后的发展方向。 相似文献
87.
Ram LC Srivastava NK Tripathi RC Jha SK Sinha AK Singh G Manoharan V 《Journal of environmental management》2006,79(2):173-187
Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed. 相似文献
88.
Grasslands were once widespread and species-rich ecosystems. They have drastically decreased throughout the world, largely due to changes in land-uses. Remnant grasslands are often highly degraded and disconnected and require active conservation. In order for grasslands to be maintained worldwide, protected areas need to be created. While adequately creating and managing protected areas has proven difficult, this can be improved by following a three-point guideline: (1) consider many ecological groups (birds, insects, plants); (2) use conservation biology knowledge; (3) seek agreements with concerned parties by comprehending elements of economy, politics and sociology. Based on the example of La Crau, a steppe area in South-eastern France, this review aims at (i) illustrating that this guideline can facilitate creating and managing protected areas and (ii) proposing improvement to the guideline while keeping it simple. In La Crau, the need for conservation was first acknowledged in 1975. Between 1983, when a request for a protection decree was made and 1990, when the first concrete protection measure was taken, 20% of the steppe disappeared. It took another 8 years to reach a concerted management plan in 1998. The review shows how using ecological guidelines would have helped better and faster protection of the steppe. Improvements to the guideline drawn from the La Crau experience include: the protection of some traditional practices; the protection of some degraded habitats that can substitute for habitats that no longer exist; the restoration of degraded habitats that do not qualify for protection; and the flexibility of the management plan. 相似文献
89.
Geographical areas constitute the basic implementation locus for integrated coastal zone management strategies and activities.
Because the definition of territorial planning objectives may be affected by socioeconomic and environmental characteristics,
one of the main steps in the process involves dividing the coast into homogeneous environmental management units (HEMUs).
This article presents a general and simple method for regionalizing the landside of a coastal zone into HEMUs and illustrates
it through application to the Catalan coast. Socioeconomic and natural (biophysical) subsystems were selected as the most
appropriate dimensions of the regionalization process. Dimensions were described using 11 spatial themes, which were managed
in a geographic information system environment that proved to be an adequate tool for the purpose. A final coastal zone map
of four classes of HEMUs connected to local administrative units was obtained, and because it reflects the current natural
and socioeconomic dynamics, it can be considered as an initial step in the planning process for the Catalan coast. Although
the proposed method was developed based on the characteristics of the Catalan coast, it is general enough to be adapted and
applied to most developed or developing coastal areas. 相似文献
90.
Assessing Impacts of Typhoons and the Chi-Chi Earthquake on Chenyulan Watershed Landscape Pattern in Central Taiwan Using Landscape Metrics 总被引:3,自引:1,他引:2
The Chi-Chi earthquake (ML = 7.3) occurred in the central part of Taiwan on September 21, 1999. After the earthquake, typhoons Xangsane and Toraji produced
heavy rainfall that fell across the eastern and central parts of Taiwan on November 2000 and July 2001. This study uses remote
sensing data, landscape metrics, multivariate statistical analysis, and spatial autocorrelation to assess how earthquake and
typhoons affect landscape patterns. It addresses variations of the Chenyulan watershed in Nantou County, near the earthquake’s
epicenter and crossed by Typhoon Toraji. The subsequent disturbances have gradually changed landscape of the Chenyulan watershed.
Disturbances of various types, sizes, and intensities, following various tracks, have various effects on the landscape patterns
and variations of the Chenyulan watershed. The landscape metrics that are obtained by multivariate statistical analyses showed
that the disturbances produced variously fragmented patches, interspersed with other patches and isolated from patches of
the same type across the entire Chenyulan watershed. The disturbances also affected the isolation, size, and shape-complexity
of patches at the landscape and class levels. The disturbances at the class level more strongly affected spatial variations
in the landscape as well as patterns of grasslands and bare land, than variations in the watershed farmland and forest. Moreover,
the earthquake with high magnitude was a starter to create these landscape variations in space in the Chenyulan watershed.
The cumulative impacts of the disturbances on the watershed landscape pattern had existed, especially landslides and grassland
in the study area, but were not always evident in space and time in landscape and other class levels. 相似文献