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51.
In India, rain water and atmospheric aerosols are observed to bealkaline in nature due to the influence of soil-derivedparticles which are rich in components like Ca and Mg. Thesecomponents increase the neutralization potential of rain waterand have a greater influence at rural site compared to urbansite. However, if there are continuous rains, the concentrationof crustal components becomes lower resulting in lower pH ofrain water. Unlike the characteristics of rain water oncontinent, the pH of rain water has been observed to be acidicin all the events over the Indian Ocean during Pre-campaigns ofIndian Ocean Experiment (INDOEX). The possible reason for acidicrains over Indian Ocean could be the anthropogenic contributionfrom continent transported by NE winds coming towards the oceanduring this period.  相似文献   
52.
Mandatory disclosure of corporate social responsibility (CSR) reporting forces supply chain members to consider CSR issues in developed countries. Researchers have viewed CSR content within different themes, such as human (social), ethical and environmental perspectives. So far, in India, very little research has been done to study the impact of human issues in employment (social), ethical issues in business operations and pollution (environmental) issues at both regional and specific sector level. This paper emphasises the perspective view of supplier selection, considering CSR issues as opposed to traditional methods using conventional selection criteria such as cost, quality, delivery and service. It employs six CSR criteria such as discrimination, abuse of human rights, child labour, long working hours, unfair competition and pollution to assess small- and medium-sized suppliers who produce and deliver products to the automotive and textile industry sectors. The results of this study indicate that to prevent discrimination against pay variation, minimise cases of abuse of human rights and incidence of child labour, suppliers must put in place proper policies and procedures regarding employment contract, identification and verification records. Furthermore, to reduce unfair competition, suppliers of both automotive and textile sectors may introduce processes for investigating reports of unethical conducts and take severe disciplinary action. The suppliers of both automotive and textile sectors believe that the competitive advantage can be achieved through environmental oriented business practices. However, they differ in their approaches in attaining this objective.  相似文献   
53.
Abstract:  Pteropus livingstonii , P. voeltzkowi , and P. rodricensis are three critically endangered fruit bats from western Indian Ocean islands for which multidisciplinary conservation programs have been established that include environmental education programs (EEPs). We describe these EEPs in terms of the strategies used to achieve them and evaluate the educational and conservation outcomes and impacts of the programs. Educational outputs (including posters, stickers, videos, lesson plans, and workshops), primarily linking human needs to the ecosystem services provided by bats, were delivered to schools and community groups, and local environmental educators were trained to further develop the EEPs. Outcomes included increased local awareness about the bats and their conservation, training of environmental educators, inclusion of bat conservation and environmental issues in the school curricula, and establishment of community-based environmental nongovernmental organizations (NGOs). Extensive prior planning, presentations in local languages, distribution of outputs through existing networks of educators, training of local educators, establishment of local environmental NGOs, and local capacity-building were all associated with these EEPs achieving their goals in the under-resourced island locations where these bats are found. The EEPs were also important in the development of other components of their respective conservation programs, such as population monitoring programs. Although long-term conservation impacts, particularly tackling habitat loss, are slow to materialize and social and economic issues need to be addressed, these EEPs have already had important outcomes and have established the foundation for future conservation actions.  相似文献   
54.
Abstract: Mid‐range streamflow predictions are extremely important for managing water resources. The ability to provide mid‐range (three to six months) streamflow forecasts enables considerable improvements in water resources system operations. The skill and economic value of such forecasts are of great interest. In this research, output from a general circulation model (GCM) is used to generate hydrologic input for mid‐range streamflow forecasts. Statistical procedures including: (1) transformation, (2) correction, (3) observation of ensemble average, (4) improvement of forecast, and (5) forecast skill test are conducted to minimize the error associated with different spatial resolution between the large‐scale GCM and the finer‐scale hydrologic model and to improve forecast skills. The accuracy of a streamflow forecast generated using a hydrologic model forced with GCM output for the basin was evaluated by forecast skill scores associated with the set of streamflow forecast values in a categorical forecast. Despite the generally low forecast skill score exhibited by the climate forecasting approach, precipitation forecast skill clearly improves when a conditional forecast is performed during the East Asia summer monsoon, June through August.  相似文献   
55.
中国代际降水区域变化差异分析   总被引:1,自引:0,他引:1  
利用中国气象中心160站点的夏季降水实际观察资料,对中国半个世纪的降水变化按年代进行了系统分析,并对各地的代际降水量变化趋势进行了区域对比。结果发现,降水变化幅度大的区域主要集中在季风区,而非季风区的年代际降水相对稳定。在多数情况下,以四川为中心的区域的降水量变化与东北的北部一致,东南沿海与渤海湾沿岸区域一致。季风区降水量变化的区域差异,可能既受季风的年代际强弱变化的影响,又受微地形的影响:  相似文献   
56.
An assessment of human interference in Kedarnath Wildlife Sanctuary (KWLS) showed huge dependence of local communities on forest fringes. KWLS is under active consideration as a national park because of its unique flora and fauna. Studies have evidenced habitat destruction and successional changes in the area because of ongoing unsustainable harvesting and logging. The present study provides an integrated approach towards evaluating resource extraction and management of the sanctuary. The study was based on in-depth semi-structured interviews and group discussions with local inhabitants of six villages and with forest officials. In addition, regeneration patterns and vegetation analysis was conducted in three land tenurial systems: community forest (CF), reserve forest (RF) and protected forest (PF). Key issues identified were wildlife offences, encroachment, pressure from unsustainable harvesting of resources and lack of livelihood opportunities. Ecological studies showed continuous change in regeneration patterns in forest patches/stands. The local survey stressed managing sanctuary fringes considering the village economy, social issues and resource requirements, and enhancing on-farm resource production to reduce pressure on forests. Forest personnel demanded more training on encroachment and poaching, these being major threats to biodiversity and bio-resources. Supporting and providing better livelihood opportunities is a viable option for minimizing pressure and managing biodiversity of the area through active community participation. This study generated useful outcomes and strategies for advancing policies to reduce pressure and overcome management constraints in the sanctuary.  相似文献   
57.
随着森林生态系统的正向演替,植物物种多样性、群落结构、生产力以及土壤条件均会发生显著的变化,这些变化对菌根类型和多样性会产生不同程度的影响。为了探讨群落结构和功能的变化对菌根资源可能产生的影响,选择季风常绿阔叶林及其演替系列上的代表性森林生态系统为对象,对菌根化根系、菌根类型和菌根真菌孢子密度进行调查,并结合已有的群落信息和土壤养分状况,分析在森林演替过程中菌根资源的变化情况和可能的影响因素。结果表明:季风常绿阔叶林各演替阶段的森林生态系统中菌根化比例接近70%,但不同演替阶段森林的优势菌根类型存在明显的差异。处于演替初期的马尾松(Pinus massoniana)林以丛枝菌根为主,占菌根总数的78%;演替中期的针阔叶混交林中的外生菌根占有绝对优势,占75%,是丛枝菌根的3倍;演替顶级的季风常绿阔叶林中的外生菌根和丛枝菌根的比例相当。马尾松林的菌根真菌孢子密度最高,每20 g风干土壤中的孢子数量高达2 925个,是针阔叶混交林的2.5倍,季风常绿阔叶林的2倍。演替系列上的森林生态系统的菌根类型的差异与植物物种多样性和群落结构,尤其是林下的灌木、草本层密度存在一定的相关性,同时也受土壤养分状况的影响。马尾松林具有较丰富的草本植物和较高的草本层密度,并且该森林的土壤相对贫瘠,这些条件都有利于丛枝菌根真菌侵染草本植物的根系形成丛枝菌根并产生大量孢子。针阔叶混交林中外生菌根的优势主要受该森林中外生菌根植物在群落组成上的绝对优势影响。季风常绿阔叶林的物种丰富,群落结构复杂,因此该森林呈现了两种类型菌根优势相当的现象。该文的结果表明,随着季风常绿阔叶林演替的进行,菌根资源在类型上会出现较大的分异,而这种变化受植物物种数量、群落结构的影响,与土壤养分状况存在一定的关系,并且不同演替阶段森林生态系统影响菌根组成的因素存在差异。  相似文献   
58.
《Environmental Hazards》2013,12(3):249-265
This paper discusses insights from post-tsunami early warning system (EWS) development in Thailand, Sri Lanka and Indonesia by analysing selected elements of resilience, based on the Coastal Community Resilience (CCR) framework, and by distinguishing between the cognitive, normative and procedural dimensions of EWSs. The findings indicate that (1) recent calls to develop participatory and people-centred EWSs as promoted by the Hyogo Framework for Action 2005—2015 have not been sufficiently translated into action in the implementation of national policies and strategies for early warning; (2) policy and guidance places significantly more emphasis on the procedural compared to the normative and cognitive dimensions of EWSs; (3) practitioners engaged in early warning and disaster risk reduction operate in contexts shaped by multiple stakeholder agendas and face considerable challenges in negotiating diverse needs and priorities; and (4) few platforms currently exist that enable stakeholders to coordinate and reconcile agendas, negotiate joint targets, share knowledge and critically reflect on lessons learnt, and to improve the integration of early warning with other priorities such as livelihoods improvement, natural resource management and community development.  相似文献   
59.
ABSTRACT: The ground water in the Tucson basin is being drawn faster than it is replenished by nature. The water table is falling, giving rise to several conflicts between water users in the basin. At present, several lawsuits are in progress, including an action by the Papago Tribe against some of the major water users in the basin. Largely because of these difficulties, the State Legislature has established a commission to make proposals for the reform of Arizona's ground water law. The pattern of water use in the basin will undoubtedly be changed by the outcome of the present litigation and the coming reform of Arizona's ground water law. This paper describes how water use in the basin might be affected by changes in the availability of water and gives an account of the effects that these changes in water use could have on the region's economy. The paper concludes that the water problems of the Tucson basin will have little effect on the region at large and that these problems are simply a matter for the Indians and the other water users in the basin to sort out amongst themselves.  相似文献   
60.
中国东部海域发生海啸的可能性分析   总被引:3,自引:0,他引:3  
由强地震引发的印度洋大海啸在短短几个小时内就演变成了一场巨大的人间惨剧。这样的2004年12月26日自然灾害,人类能不能预防?它的形成机制是什么?我国历史上发生过海啸吗?在未来我国哪些地区会发生海啸?就上述问题,作了可能性分析。印度洋海啸的发生可以说既是天灾,也是人祸。人类虽说还不能控制地震、海啸等天灾的发生,但可以通过预报等措施来减轻它们造成的损失。我国历史时期曾发生过多次海啸,台湾周围海域是海啸的高发区域,其次是大陆架区域,渤海是低发区域。在未来,东海、南海,特别是台湾岛附近海域具备产生海啸的条件,即海南、台湾存在成灾条件;其次是上海,广州,也存在潜在的海啸危险;沿海其它城市亦应居安思危。  相似文献   
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