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人地协同论:可持续发展模型构建的基础 总被引:6,自引:0,他引:6
人地协同论是在陆地系统科学、非线性系统理论基础上建立起来的关于可持续发展的一个数理模型,它以社会与自然的交互作用、交界面性质及其演化规律为研究对象。本文根据系统生态学理论,提出了关于可持续生存的数学定义。 相似文献
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上海市空气质量变化的多重分形分析 总被引:3,自引:0,他引:3
以上海市2000年7月至2006年6月的污染指数时间序列为基础数据,引入多重分形分析方法对上海市的大气污染特征及其变化趋势进行了研究.研究表明,上海市的3种主要大气污染物(SO2、NO2和PM10)在整个时间尺度上均表现出标度不变性,具有完全不同的多重分形特征.多重分形分析方法不仅能确认序列中的标度不变性,而且能说明3种大气污染物序列中概率分布的标度变化,这对于描述大气污染物时间序列的动力学变化具有现实意义.另外,进一步应用3个多重分形谱参数(B、△a和△f),研究了3种大气污染物各年的多重分形谱的变化,并结合上海市采取的大气环境治理措施,对其变化的原因进行了分析.结果表明,多重分形谱参数可作为一个评价城市空气质量演变程度的综合定量指标.为分析城市空气质量的演变提供了一条新的途径,对于认识上海市城市空气质量的变化过程和科学制订环境保护决策具有重要意义. 相似文献
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Shi Lu Du Nanshan Yuan Yinghui Shu Sheng Sun Jin Guo Shirong 《Environmental science and pollution research international》2016,23(18):18277-18287
Environmental Science and Pollution Research - Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. cucumerinum (FOC) is the most severe soil-borne disease attacking cucumber. To assess the... 相似文献
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Coal is not only an important energy source in China but also a major source of air pollution. Because of this, China’s national
sulfur dioxide (SO2) emissions have been the highest in the world for many years, and since the 1990s, the territory of China’s south and southwest
has become the third largest acid-rain-prone region in the world. In order to control SO2 emissions, the Chinese government has formulated and promulgated a series of policies and regulations, but it faces great
difficulties in putting them into practice. In this retrospective look at the history of SO2 control in China, we found that Chinese SO2 control policies have become increasingly strict and rigid. We also found that the environmental policies and regulations
are more effective when central officials consistently give environmental protection top priority. Achieving China’s environmental
goals, however, has been made difficult by China’s economic growth. Part of this is due to the practice of environmental protection
appearing in the form of an ideological “campaign” or “storm” that lacks effective economic measures. More recently, better
enforcement of environmental laws and regulations has been achieved by adding environmental quality to the performance assessment
metrics for leaders at all levels. To continue making advances, China needs to reinforce the economic and environmental assessments
for pollution control projects and work harder to integrate economic measures into environmental protection. Nonetheless,
China has a long way to go before economic growth and environmental protection are balanced. 相似文献
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Zili Zhang Jian Wang Lianghua Chen Xinyu Chen Guiyuan Sun Nanshan Zhong Haidong Kan Wenju Lu 《Environmental science and pollution research international》2014,21(6):4236-4244
Guangzhou is a metropolitan in south China with unique pollutants and geographic location. Unlike those in western countries and the rest of China, the appearance of haze in Guangzhou is often (about 278 days per year on average of 4 years). Little is known about the influence of these hazes on health. In this study, we investigated whether short-term exposures to haze and air pollution are associated with hospital admissions in Guangzhou. The relationships between haze, air pollution, and daily hospital admissions during 2008–2011 were assessed using generalized additive model. Studies were categorized by gender, age, season, lag, and disease category. In haze episodes, an increase in air pollutant emissions corresponded to 3.46 (95 % CI, 1.67, 5.27) increase in excessive risk (ER) of total hospital admissions at lag 1, 11.42 (95 % CI, 4.32, 18.99) and 11.57 (95 % CI, 4.38, 19.26) increases in ERs of cardiovascular illnesses at lags 2 and 4 days, respectively. As to total hospital admissions, an increase in NO2 was associated with a 0.73 (95 % CI, 0.11, 1.35) and a 0.28 (95 % CI, 0.11, 0.46) increases in ERs at lag 5 and lag 05, respectively. For respiratory illnesses, increases in NO2 was associated with a 1.94 (95 % CI, 0.50, 3.40) increase in ER at lag 0, especially among chronic obstructive pulmonary disease. Haze (at lag1) and air pollution (for NO2 at lag 5 and for SO2 at lag3) both presented more drastic effects on the 19 to 64 years old and in the females. Together, we demonstrated that haze pollution was associated with total and cardiovascular illnesses. NO2 was the sole pollutant with the largest risk of hospital admissions for total and respiratory diseases in both single- and multi-pollutant models. 相似文献
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加强区域性中心城市建设在西部大开发中的作用 总被引:6,自引:0,他引:6
在分析区域性中心城市的条件和作用的基础上,针对目前西部区域城市发展体系的严重不完备,强调培育功能健全,经济发达,具有相当规模的区域性中心城市在实施西部大开发中的重要性与迫切性。 相似文献
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煤矿开采沉陷对耕地永续利用的影响分析 总被引:7,自引:0,他引:7
本文结合开采沉陷学和环境土壤学的理论,详细分析了煤炭开采造成的地面沉陷对耕地永续利用的影响,将有助于人们提高认识,组织开展沉陷地复垦利用,促进矿区耕地永续利用。 相似文献
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