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901.
902.
903.
This article adopts Multivariate Adaptive Regression Spline (MARS) for prediction of Angle of Shearing Resistance(?) of soil. MARS is an adaptive, non-parametric regression approach. Percentages of fine-grained (FG), coarse-grained (CG), liquid limit (LL), and bulk density (BD) have been used as input variables of MARS. The developed MARS gives an equation for prediction of ? of soil. The results of MARS have been compared with Genetic Expression Programming (GEP), Artificial Neural Network (ANN), and Adaptive Neuro Fuzzy Inference System (ANFIS) models. These results demonstrate that the developed MARS can be used as a robust model for determination of ? of soil. 相似文献
904.
Turning the curve: A critical review of Kuznets approaches 总被引:1,自引:0,他引:1
905.
Babatunde Anifowose Damian M. Lawler Dan van der Horst Lee Chapman 《Applied geography (Sevenoaks, England)》2012,32(2):636-651
In countries with insufficient investments in infrastructure and weak environmental governance, oil leakage from pipelines often occurs as a result of poor management and maintenance. Nigeria has its share of such incidents, but also, it suffers a large number of deliberate attacks (‘interdictions’) on oil pipelines. Often these attacks are accompanied by oil theft, carried out by well-equipped professionals and/or at a smaller scale by opportunistic local residents. The causes of these attacks, and the extent of subsequent damage to local communities and the environment, are obscured by a complex web of stakeholders, claims and actions. Any efforts to mitigate the negative impacts of interdiction on the environment and people require a better understanding of its spatiotemporal pattern of occurrence. This article presents a first quantitative and regional exploration of the problem of oil pipeline interdiction in Nigeria. It illustrates geographic patterns through choroplethic and bivariate GIS (Geographical Information Systems) map overlays. We examine interdiction statistics, identify spatiotemporal patterns and discuss correlations with socioeconomic factors. Findings include: (a) strong negative correlation between pipeline interdiction and poverty; and (b) statistically and non-statistically significant mean differences in the pattern of interdiction occurrence amongst the five geographic regions. Finally, we highlight the need for much better data collection and reporting for the mitigation of the negative socio-environmental impacts of interdiction incidences. 相似文献
906.
《Norsk geografisk tidsskrift. Norwegian journal of geography》2012,66(4):265-270
The development of new technology for use in environmental research provides us with numerous sophisticated tools such as remote sensing and Geographical Information Systems (GIS). However, throughout recent decades there have been debates regarding the appropriate use of these tools. The question still remains as to whether they can strengthen environmental research, or whether perhaps more conventional methods are better suited? This paper focuses on the use of remote sensing in environmental applications, such as strategic or regional environmental assessments. By providing a case study from Sri Lanka, it is shown how the benefits from a visual interpretation of satellite imagery can be combined with a digital supervised classification in a hybrid approach. The use of these techniques in environmental assessments is further discussed in the light of 'best practicable science' as proposed by the International Association of Impact Assessment (IAIA). The intention is not to discourage the use of digital techniques, but to discuss how they should be utilized to their fullest extent. The approach argued for here provides data of a more general and possibly integrative nature. It may therefore be well suited for the early screening and scoping stages of environmental assessments at a landscape level. 相似文献
907.
908.
论中国城市生态健康与环境污染修复 总被引:1,自引:0,他引:1
从大气污染、水体污染、固体废弃物污染、噪声污染和土壤污染体等方面,对中国城市生态健康面I临的问题和环境污染现状进行了分析研究。结果表明,城市环境污染形势依然严峻,城市生态健康受到严重威胁,日益成为制约城市健康发展的主要因素。在此基础上,提出了中国城市环境污染修复的建议,认为保持生态健康,城市环境污染的物理和化学修复措施结合生物修复,是构成生态修复的重要要素。在实际修复过程中,把物理修复、化学修复和生物修复更好地结合起来,才能形成有效的生态修复技术。应该进一步增强城市生态健康意识,复合的城市生态系统还需用系统、生态的方法对城市环境污染进行修复,以实现可持续发展和构建和谐社会。 相似文献
909.
Dawn Day Biehler 《Geoforum》2009,40(6):1014-1023
This paper traces changes in the political ecology of insects and chemicals in US public housing since Congress founded public housing in 1937. Drawing upon the literature of critical geographies of home, urban political ecology, and medical history, it argues that the constitution of “public” and “private” space within public housing was deeply entangled with pest control practices there. Prior to 1945, reformers treated the housing as a commons, in part compelled by the mobility of bedbugs and the pesticide used to combat them, both of which were seen as serious health threats. Managers were also motivated by social welfare ideologies, while residents eagerly assisted with communal control policies in order to achieve freedom from the health insults of bedbugs. Following 1945, however, new synthetic pesticides like DDT seemed to stay safely within one apartment unit, encouraging housing managers to abandon community-oriented pest control practices. Meanwhile, curtailed budgets, particularly after the Housing Act of 1949, left the infrastructure of public housing to decay, rendering units more physically permeable even as managers neglected the communities there. The new pesticides nearly eradicated bedbugs, but tenacious populations of German cockroaches blossomed thanks to the permeable buildings and synthetic pesticides. Residents grew increasingly resistant to pesticide use as they observed that cockroach populations went unabated. The paper serves as a case for applying political ecology frameworks to domestic spaces, and also argues that housing quality and domestic pesticide use are not merely private responsibilities but should be regarded as environmental justice issues. 相似文献
910.
Based on this preliminary study, existing sand and gravel mining regulations (in Maine, USA) can be inferred to provide some
protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water. How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination
is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure
the effectiveness of mining regulations. The sand and gravel aquifer system studied is covered with former and active gravel
pits to nearly 25% of its areal extent. Data from homeowner interviews and field measurements found scant evidence of changes
in water quantity. Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable
to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities. 相似文献