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11.
三种固体废弃物综合利用的初步研究 总被引:6,自引:0,他引:6
从环境建设的可持续发展出发 ,结合天津开发区在基础设施及园林绿化建设中面临土源紧缺以及周边地区存在大量的海湾泥、粉煤灰、碱渣土等固体废弃物的现实 ,在详细研究了3种废物的物理、化学性质的基础上探讨了用这些废物代替农田客土的可行性。实验及推广应用结果表明 ,这些废物按适当比例混合后能够形成一种可替代种植客土的新型土壤 ,这种新型土壤的最佳配比(即海湾泥与粉煤灰或碱渣土 )比例为3:1 ,同时该配比基质对植物生长的适宜性优于滨海盐土。 相似文献
12.
SeawaterintrusionincoastalareasofYellowSeaandBohaiSeaShengXuebin;SunJianzhong;DaiZhaohua(ResearchCenterforEco-EnvironmentalSe... 相似文献
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Oliveira Amauri P. Bornstein Robert D. Soares Jacyra 《Water, Air, & Soil Pollution: Focus》2003,3(5-6):3-15
The major topographic, mesoscale, and urban influences on the wind patterns of the City of São Paulo are characterized using one year of surface wind velocity data observed at 11 surface stations within its urban limits. The data was used to study the diurnal and annual variations of wind velocity and horizontal wind divergence within the city. Results showed that the circulation over the investigated area is dominated by three major factors: sea breeze; mountain-valley circulations; and urban effects, such as roughness, building-barrier, and urban heat island. The sea breeze was found to be the dominant feature of the monthly-averaged diurnal variation of São Paulo surface winds during the eight warmest months of the year. The sea breeze front induces a velocity minimum at the time of its passage and a post-frontal afternoon velocity maximum. Mountain-valley thermal effects on the flow can be seen in the temporal divergence/convergence patterns. These thermal effects tend to be more important during colder months, at night, and when the wind velocities are low. Nighttime downslope convergent flows are present over the city during winter and spring and daytime upslope divergent flows are present over the city during summer months. 相似文献
17.
浅谈秦皇岛近海海域生态环境保护措施 总被引:3,自引:1,他引:3
杨俊 《中国环境管理干部学院学报》2003,13(3):49-51,57
为了使海域的生态良性循环和海洋资源的可持续发展,本文根据秦皇岛近海海域生态 环境存在的严重问题,从多方面,不同角度,对该海域的生态保护提出了切实可行的保护措施。 相似文献
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基于GIS技术的海塘防洪减灾信息系统 总被引:2,自引:0,他引:2
海塘工程的规划、设计、建设、维护和管理,对沿海省份经济发展和人民生命财产的安全十分重要,历来受到政府和沿海居民的高度重视.介绍了基于GIS技术的海塘防洪减灾信息系统的主要功能及逻辑结构,分析了海塘数据库的特点,详细讨论了海塘属性和空间数据库的建库内容及方法.最后通过应用实例,验证了系统技术路线的合理性、正确性和实用性. 相似文献
19.
The Water Fluxes of the Yellow River to the Sea in the Past 50 Years, in Response to Climate Change and Human Activities 总被引:12,自引:1,他引:12
Jiongxin X 《Environmental management》2005,35(5):620-631
Since the 1970s, the water fluxes to the sea of the Yellow River have declined significantly. Based on data of precipitation, air temperature, the measured and “natural” river flow, the water diversion and consumption, and the areas of erosion and sediment control measures over the drainage basin, water fluxes to the sea of the Yellow River are studied in relation with the influences of changing climate and human activities. The Yellow River basin can be divided into different water source areas; multiple regression indicates that the variation in precipitation over different water source areas has different effect on water fluxes to the sea. In the period between 1970 and 1997, averaged air temperature over the whole Yellow River increased by about 1.0°C, from 16.5°C to 17.5°C, a factor that is negatively correlated with the water yield of the Yellow River. Water diversion and consumption has sharply increased and resulted in a significant decline in the water fluxes to the sea. Since the 1960s, erosion and sediment control measures have been practiced over the drainage basin. This factor, to a lesser degree, is also responsible for the decrease in water fluxes to the sea. A multiple regression equation has been established to estimate the change in water fluxes to the sea caused by the changes in precipitation, air temperature, water diversion and consumption, erosion, and sediment control measures, indicating that the contribution of water diversion and consumption to the variation in annual water flux to the sea is 41.3%, that of precipitation is 40.8%, that of temperature is 11.4%, and that of erosion and sediment control measures is 6.5%. 相似文献
20.
《Journal of Environmental Economics and Management》2014,67(3):639-655
By signing a water sharing agreement (WSA), countries agree to release an amount of river water in exchange for a negotiated compensation. We examine the vulnerability of such agreements to reduced water flows. Among all WSAs that are acceptable to riparian countries, we find out the one which is self-enforced under the most severe drought scenarios. The so-called upstream incremental WSA assigns to each country its marginal contribution to its followers in the river. Its mirror image, the downstream incremental WSA, is not sustainable to reduced flow at the source. Self-enforcement problems can be solved by setting water releases and compensations contingent to water flow. We apply our analysis to the Aral Sea Basin. We compute the upstream incremental compensations for the Bishkek agreement and asses its vulnerability with historical flows. 相似文献