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961.
惠阳城区降雨径流重金属污染特征研究:Ⅰ.地表堆积物重金属含量分析 总被引:2,自引:0,他引:2
以惠阳城区为研究对象,选取4种具有代表性的典型城市功能区类型:工业区、商业区、住宅区、交通区,对其地表堆积物进行样品采集和实验分析.结果表明:地表堆积物细粒部分(粒径<149舯)所占比例为51%,粗粒部分(粒径>2 000um,)所占比例仅4.1%;重金属含量的粒径分级特性和质量分数相似,即粒径越细的部分重金属含量越高;Pb,Zn,Cu.Cr之间的相关系数较高;重金属的浸出浓度在不同的功能区基本遵循同样的规律,即细粒部分重金属浸出浓度最高,随粒径的增大浸出浓度逐减,细粒部分重金属的浸出浓度:w(Pb)为59.1 rag/kg/kg,w(Zn)为93.5 mg/kg,w(Cu)为37.7 ms/ks,w(Cr)为23.9 ms/kg,w(Cd)为0.07 mg,kg. 相似文献
962.
963.
呼和浩特市十年地表水环境质量趋势分析 总被引:1,自引:0,他引:1
本文根据呼和浩特市十年来河流水质监测数据,选取高锰酸盐指数(CODMn)、生化需氧量(BOD5)、氨氮、挥发酚、汞、铅和石油类七项指标,运用水质综合指数法(P法),分析呼和浩特市地表水十年来的变化趋势及污染特点,提出了治理地表水污染的思路。 相似文献
964.
环境与健康是人类永恒的主题。本文介绍了环境与健康的关系,总结了在全球气候变化、臭氧层损耗、生物多样性的丧失、土地荒漠化和干旱、环境污染以及城市化等多方面给人类健康带来的影响,探讨了人体总暴露研究、地理信息系统技术在本领域的应用,最后概括了我国在这一领域的研究现状。 相似文献
965.
Vulnerability assessment and adaptation to the impacts of sea level rise on the Kingdom of Bahrain 总被引:2,自引:0,他引:2
S. Al-Jeneid M. Bahnassy S. Nasr M. El Raey 《Mitigation and Adaptation Strategies for Global Change》2008,13(1):87-104
This paper assesses quantitatively the impact of sea level rise (SLR) at the global and regional scale as a result of climate
change (CC) on the coastal areas of the Kingdom of Bahrain’s islands (36 Islands). The standard Intergovernmental Panel on
Climate Change (IPCC) guidelines was modified as appropriate for the situation of the study area. Geographic Information Systems
(GIS) coupled with Remote Sensing (RS) were used as the main techniques of collecting, analyzing, modeling simulating and
disseminating information to build SLR scenarios in a geographically referenced context. Also, these tools were used to assess
vulnerability and risk of the coastal area of the islands with the expectation that coastal planner and government authorities
will profit from integrating these knowledge into a broad based environmental decision making. Three SLR scenarios: low, moderate
and high were developed to examine the impacts from SLR on all islands. The low SLR scenario (Optimistic) assumes a 0.5-m
rise above current sea level, the moderate scenario (Intermediate) assumes a one meter rise, and the high scenario (Pessimistic)
assumes a 1.5 m rise in sea level. Two more SLR scenarios were assumed to perform risk analysis, a 2 and 5 meter rise above
current sea level. The simulation of SLR are quite straightforward, emphasizing on the uses of both of the data that are incorporated
from the satellite images and the created Digital Elevation Model (DEM) to estimate SLR scenarios that are adapted in the
study. These data were used to predict consequences of the possibility of the rise in sea level at different scenarios which
may alter the landuse and patterns of human communities. Results indicate that low-lying coastal areas of Bahrain islands
are at risk from the effects of any SLR resulting from CC. These islands are vulnerable under different SLR Scenarios. More
than 17% of the country total area may be inundated under 1.5 m SLR in 2100. The total area that might be lost under different
sea level scenarios will vary from more than 77 km2 if SLR reaches 0.5 m, to about 100 km2 under 1.0 m SLR and may reach 124 km2 under 1.5 m SLR scenario. The total inundated areas due to risk scenarios will reach 133 km2, if the SLR rises to 2.0 m, and it is estimated to be more than (22%) of the main island total area. Under the second scenario,
if the SLR reaches 5.0 m, the main islands will lose approximately half of its area (47%) equal to 280 km2. Hawar islands group will lose about (30%) of its total area under 2.0 m SLR, which is about 15.5 km2.A SLR adaptation policy framework (APF) and adaptation policy initiatives (APIs) are suggested for planners to build upon
for reducing the likely effects of SLR in the Kingdom of Bahrain. The framework is composed of four steps namely, acquisition
of information, planning and design, implementation and monitoring and evaluation. A general policy framework for a national
response to SLR is suggested. Additionally, a range of policy adaptation options/initiatives to sustain coastal developments
under the likely effects of SLR are recommended. 相似文献
966.
Kenneth T. Gillingham Steven J. Smith Ronald D. Sands 《Mitigation and Adaptation Strategies for Global Change》2008,13(7):675-701
In the coming century, modern bioenergy crops have the potential to play a crucial role in the global energy mix, especially
under policies to reduce carbon dioxide emissions as proposed by many in the international community. Previous studies have
not fully addressed many of the dynamic interactions and effects of a policy-induced expansion of bioenergy crop production,
particularly on crop yields and human food demand. This study combines an updated agriculture and land use (AgLU) model with
a well-developed energy-economic model to provide an analysis of the effects of bioenergy crops on energy, agricultural and
land use systems. The results indicate that carbon dioxide mitigation policies can stimulate a large production of bioenergy
crops, dependent on the level of the policy. This production of bioenergy crops can lead to several impacts on the agriculture
and land use system: decreases in forestland and unmanaged land, decreases in the average yield of food crops, increases in
the prices of food crops, and decreases in the level of human demand of calories.
相似文献
Steven J. Smith (Corresponding author)Email: |
967.
Impacts of climate change and CO2 increase on agricultural production and adaptation options for Southern Québec, Canada 总被引:1,自引:1,他引:0
Jean-Phillipe Brassard Bhawan Singh 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):241-265
This study involves the assessment of the potential impacts of greenhouse gas climate change and changing ambient carbon dioxide
(CO2) levels on crop yields in Quebec, Canada. The methodology involves coupling the transient diagnostics of two Atmosphere-Ocean
General Circulation Models, namely the Canadian CGCM1 and the British HadCM3, to the Decision Support System for Agrotechnology
Transfer (DSSAT) 3.5 crop models to simulate current (1961–1990) and future (2040–2069) crop yields and changes. This is done
for four different crop species, namely spring wheat, maize, soybean, and potato, and for seven agricultural regions of Southern
Quebec. The results of this study focus on the main causative factors influencing crop yields, namely the direct CO2 fertilization effect, the influence of the increase in growing season temperature, including optimal thermal conditions and
acceleration in crop maturation, soil moisture availability, as influenced by precipitation and evapotranspiration, and nitrogen
uptake by crops. Our results show that crop yield changes may vary according to climate scenario, crop species, and agricultural
region. Consistent with other similar research, it would seem that these multiple causative factors very often seem to cancel
each other out and dilute the impacts of climate change on crop yields. 相似文献
968.
969.
自50年代初至2001年,50年来虎林市境内以平原沼泽型为主的湿地面积损失了三分之二,引起灾害性气候增加,造成了一定程度的农业损失,文章通过公式计算得出了农业损失值。 相似文献
970.
系统响应气候变化脆弱性定量评价国内研究综述 总被引:2,自引:0,他引:2
定量评价气候变化脆弱性是人类采取适应性措施应对全球气候变化,以减少其不利影响的关键和基础。在对气候变化脆弱性有关概念进行讨论,及对国际、国内系统响应气候变化脆弱性评价研究回顾的基础上,对中国近十几来有关气候变化脆弱性定量评价研究的成果从三个方面进行了较为系统的总结:气候情景的模拟预测、系统变化过程的模拟、脆弱性指标的选取及脆弱性层次的划分。最后,从评价对象、技术手段、指标体系、时间尺度等方面探讨了该领域研究的不足及发展方向。 相似文献