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111.
ABSTRACTThe automated classification of ambient air pollutants is an important task in air pollution hazard assessment and life quality research. In the current study, machine learning (ML) algorithms are used to identify the inter-correlation between dominant air pollution index (API) for PM10 percentile values and other major air pollutants in order to detect the vital pollutants’ clusters in ambient monitoring data around the study area. Two air quality stations, CA0016 and CA0054, were selected for this research due to their strategic locations. Non-linear RPart and Tree model of Decision Tree (DT) algorithm within the R programming environment were adopted for classification analysis. The pollutants’ respective significance to PM10 occurrence was evaluated using Random forest (RF) of DT algorithms and K means polar cluster function identified and grouped similar features, and also detected vital clusters in ambient monitoring data around the industrial areas. Results show increase in the number of clusters did not significantly alter results. PM10 generally shows a reduction in trend, especially in SW direction and an overall minimal reduction in the pollutants’ concentration in all directions is observed (less than 1). Fluctuations were observed in the behaviors of CO and NOx during the day while NOx displayed relative stability. Results also show that a direct and positive linear relationship exists between the PM10 (target pollutant) and CO, SO2, which suggests that these pollutants originate from the same sources. A semi-linear relationship is observed between the PM10 and others (O3 and NOx) while humidity shows a negative linearity with PM10. We conclude that most of the major pollutants show a positive trend toward the industrial areas in both stations while tra?c emissions dominate this site (CA0016) for CO and NOx. Potential applications of nuggets of information derived from these results in reducing air pollution and ensuring sustainability within the city are also discussed. Results from this study are expected to provide valuable information to decision makers to implement viable strategies capable of mitigating air pollution effects. 相似文献
112.
ABSTRACTWe greatly enjoyed reading the paper by Liu et al., which is both timely and rich in insight, as it discusses the challenges in operationalizing the water–energy–food security (WEF) nexus. The nexus approach is gaining increasing attention, both in research and in policy documents, as reflected in the number and content of published documents in the past years and highlighted by the authors. 相似文献
113.
The first significant government sponsored community‐based forest management project in Australia was initiated in Central Victoria in 2002. This paper analyses the initial stage of the Wombat Community Forest Management Pilot Project. The paper develops a functional concept of ‘effective community’ for structuring community engagement in these kinds of natural resource management projects. The effective community has characteristics in common with a community of interest, adopts a bioregional perspective, embodies the values of environmental stewardship and interacts in a fully informed way as a ‘discursive community’ (Meppam 2000). The paper offers general advice for organising effective community engagement in such projects and 12 recommendations for governments developing similar initiatives elsewhere. 相似文献
114.
Rapid economic development in the aftermath of the Chinese post-1978 reforms has resulted in a shrinking of grain grown area
in the southern and eastern regions of the country which in turn is believed to have put the marginal northern regions under
increased pressure. This paper examines key indicators of agricultural performance as well as cultivated land area development
of the pre- and post-1978 reform periods focusing on the agro-pastoral Tongliao City Prefecture, eastern Inner Mongolia. The
results are related to the village level development through a case study as well as to the provincial level. Average annual
grain per capita production increased from about 400 kg in the late 1970s to more then 1000 kg in the late 1990s. This was
achieved through a combination of intensification and reclamation of cropland, with the latter restricted to pastoral classified
counties. Production variability, in particular for the low producing counties, has also increased possibly as an effect of
the substitution of traditional mixed pattern of crops with HYV monocultures. Average living standards have improved but have
been accompanied by widening income gaps. Poor farmers’ livelihoods continue to be insecure, particularly during dry years.
Concern is raised regarding the sustainability of the rapid agricultural development; an increased use of costly fertilisers
constrains poorer farmer’s economy and may lead to deteriorating water quality while increasing irrigation depletes water
resources. 相似文献
115.
Jocelyn Papprill 《New Zealand geographer》2006,62(2):152-154
Abstract: The Untouched World Sustainable Cities Youth pilot project was held in Auckland in July 2005. This article outlines the activities that school students were involved in during the week and reflects on the nature of the learning experience. Whilst not specifically targeted at geography students or teachers, the project does support the outcomes of senior high school geography programmes. 相似文献
116.
Responding to the coffee crisis: a pilot study of farmers' adaptations in Mexico, Guatemala and Honduras 总被引:6,自引:0,他引:6
This article explores the impacts of market shocks and institutional change on smallholder livelihoods, and the challenge of adaptation in Mexico, Guatemala and Honduras. The rapid decline in coffee prices since the dissolution of the International Coffee Agreement in 1989 has had widespread and profound impacts across coffee-producing regions. The data collected in the three case studies of this project confirm the severity of the impact, particularly in the Mexican and Guatemalan communities. They also illustrate the importance of the historical relationship between farmers and public institutions in defining farmers' perception of risk, their awareness of the nature of the changes they face, and thus the flexibility of their responses to present and future uncertainty. The project's findings indicate that the existence and development of local networks among farmers, service providers and information sources may be critical for facilitating adaptation, particularly in the context of economic liberalization and globalized agriculture. 相似文献
117.
Jinwon Kim Norman L. Miller Jai-Ho Oh Jun-Seok Chung Deukkyun Rha 《Global and Planetary Change》1998,19(1-4)
We present the hydrometeorology of eastern Asia during April 1995 simulated by the Regional Climate System Model. The amount and location of simulated monthly precipitation agrees well with observations. Soil water content variation was closely correlated with precipitation. Land-surface evaporation and the surface energy budget were strongly controlled by soil moisture content. A sensitivity test with reduced initial soil moisture content suggested that near-surface soil moisture spins up quickly after heavy precipitation events. However, variations in the initial soil moisture field may alter details of the simulated precipitation which can introduce further complexity in climate simulations. 相似文献
118.
绿洲可持续性评价——以张掖绿洲为例 总被引:6,自引:1,他引:5
随着绿洲经验的发展,人口的剧增,使得人们对自然资源的需求持续扩大,再加上掠夺式经营和不合理开发,导致了绿洲生态破坏,环境污染等一系列问题,对绿洲的可持续性构成了威胁。本文以张掖绿洲为例,从资源承载力和“三生”指标分析其可持续性,从而提出走向可持续发展的对策建议。 相似文献
119.
WONG Tai-CheeDivision of GeographyNanyang Technological University Bukit Timah RoadSingapore 《地理学报(英文版)》1998,(2)
TransportandplanningisuesoftheParisRegion:aquestionofsustainabilityWONGTai-CheDivisionofGeographyNanyangTechnologicalUnivers... 相似文献
120.
持续农业及其中国态势 总被引:31,自引:0,他引:31
农业是发生在生物-自然、社会-政治、经济-技术这三重环境内各种过程的综合体,因此农业的持续性也可归纳为生态、经济、社会三重定义。持续农业在不同的空间尺度上具有不同的意义,在地方和区域尺度上就是生态农业,在国家和全球尺度上,则更注意食物及其分配问题,据此,本文分析了中国持续农业面临的挑战与具有的潜力。 相似文献