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991.
ABSTRACT This study examined the vulnerability of smallholder livestock farmers in North-West Ghana to climate change using data obtained from 200 livestock farmers obtained through the administration of a semi-structured questionnaire. The Livelihood Vulnerability Index (LVI) approach was used to examine the levels of vulnerability. The study compared the vulnerability between the Nandom district and the Lawra district. The empirical results revealed that livestock farmers are more vulnerable to climatic extremes in the Nandom district than the Lawra district. The study highlights the critical role of the government regarding education and construction of water resources, among others. 相似文献
992.
安全信息有效沟通在增强企业安全文化中的作用 总被引:1,自引:1,他引:0
在分析若干起由于安全信息沟通失效引起的事故及当前企业安全文化建设不够深入的基础上,进一步探讨安全信息有效沟通对于增强安全文化的重要作用;分析信息沟通的基本过程和基本形式及在安全管理中的应用;重点研究企业内部和外部安全信息沟通的内容和形式以及影响安全信息有效沟通的因素;提出一些提高安全信息有效沟通的建议和措施。研究表明:安全信息的有效沟通对于鼓励员工参与安全事务、获得员工合作和支持、增强企业积极的安全文化建设等方面具有重要的作用。 相似文献
993.
固体火箭发动机点火装置是固体火箭的重要组成部分,它必须在极短的时间内可靠地点燃发动机主燃药,使发动机安全稳定的工作.直列式点火系统应用于固体火箭发动机上,极大地提高了发动机的可靠性.完整的直列式钝感点火系统由直列式全电子安全与解除保险装置、脉冲功率装置、冲击片点火管组成.针对这一系统,利用Labview设计一个可视化的固体火箭发动机直列式点火实验控制系统.该系统通过PC机可与单片机进行串口通信.单片机按照安伞解保时序向直列式全电子安全与解除保险装置传输上电信号,当解保时序正确且接收到高压监测信号时触发点火管,同时采集功率脉冲装置中高压储能电容的电压.试验表明,该系统可准确地按照固体火箭发动机直列式点火时序完成点火实验. 相似文献
994.
Impacts of climate change on surface water quality in relation to drinking water production 总被引:9,自引:0,他引:9
Besides climate change impacts on water availability and hydrological risks, the consequences on water quality is just beginning to be studied. This review aims at proposing a synthesis of the most recent existing interdisciplinary literature on the topic. After a short presentation about the role of the main factors (warming and consequences of extreme events) explaining climate change effects on water quality, the focus will be on two main points. First, the impacts on water quality of resources (rivers and lakes) modifying parameters values (physico-chemical parameters, micropollutants and biological parameters) are considered. Then, the expected impacts on drinking water production and quality of supplied water are discussed. The main conclusion which can be drawn is that a degradation trend of drinking water quality in the context of climate change leads to an increase of at risk situations related to potential health impact. 相似文献
995.
Vulnerability and adaptation of European farmers: a multi-level analysis of yield and income responses to climate variability 总被引:6,自引:3,他引:3
Pytrik Reidsma Frank Ewert Alfons Oude Lansink Rik Leemans 《Regional Environmental Change》2009,9(1):25-40
Climate change will affect crop yields and consequently farmers’ income. The underlying relationships are not well understood,
particularly the importance of crop management and related factors at the farm and regional level. We analyze the impacts
of trends and variability in climatic conditions from 1990 to 2003 on trends and variability in yields of five crops and farmers’
income at farm type and regional level in Europe considering farm characteristics and other factors. While Mediterranean regions
are often characterized as most vulnerable to climate change, our data suggest effective adaptation to variable and changing
conditions in these regions largely attributable to the characteristic farm types in these regions. We conclude that for projections
of climate change impacts on agriculture, farm characteristics influencing management and adaptation should be considered,
as they largely influence the potential impacts. 相似文献
996.
Jason B. Fellman Eldon H. Franz Chelsea L. Crenshaw Denise Elston 《Environment, Development and Sustainability》2009,11(4):871-885
It has become increasingly well documented that human activities are enhancing the greenhouse effect and altering the global
climate. Identifying strategies to mitigate atmospheric carbon dioxide emissions on the national level are therefore critical.
Fossil fuel combustion is primarily responsible for the perturbation of the global carbon cycle, although the influence of
humans extends far beyond the combustion of fossil fuels. Changes in land use arising from human activities contribute substantially
to atmospheric carbon dioxide; however, land use changes can act as a carbon dioxide sink as well. A soil carbon model was
built using STELLA to explore how soil organic carbon sequestration (SOC) varies over a range of values for key parameters
and to estimate the amount of global soil carbon sequestration from livestock waste. To obtain soil carbon sequestration estimates,
model simulations occurred for 11 different livestock types and with data for eight regions around the world. The model predicted
that between 1980 and 1995, United States soils were responsible for the sequestration of 444–602 Tg C from livestock waste.
Model simulations further predicted that during the same period, global soil carbon sequestration from livestock waste was
2,810–4,218 Tg C. Our estimates for global SOC sequestration are modest in proportion to other terrestrial carbon sinks (i.e.
forest regrowth); however, livestock waste does represent a potential for long-term soil carbon gain. SOC generated from livestock
waste is another example of how human activities and land use changes are altering soil processes around the world.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
997.
Adaptation to Climate Change in Developing Countries 总被引:2,自引:0,他引:2
Ole Mertz Kirsten Halsnæs Jørgen E. Olesen Kjeld Rasmussen 《Environmental management》2009,43(5):743-752
Adaptation to climate change is given increasing international attention as the confidence in climate change projections is
getting higher. Developing countries have specific needs for adaptation due to high vulnerabilities, and they will in this
way carry a great part of the global costs of climate change although the rising atmospheric greenhouse gas concentrations
are mainly the responsibility of industrialized countries. This article provides a status of climate change adaptation in
developing countries. An overview of observed and projected climate change is given, and recent literature on impacts, vulnerability,
and adaptation are reviewed, including the emerging focus on mainstreaming of climate change and adaptation in development
plans and programs. The article also serves as an introduction to the seven research articles of this special issue on climate
change adaptation in developing countries. It is concluded that although many useful steps have been taken in the direction
of ensuring adequate adaptation in developing countries, much work still remains to fully understand the drivers of past adaptation
efforts, the need for future adaptation, and how to mainstream climate into general development policies. 相似文献
998.
Willis SG Hole DG Collingham YC Hilton G Rahbek C Huntley B 《Environmental management》2009,43(5):836-845
Global climate change, along with continued habitat loss and fragmentation, is now recognized as being a major threat to future
biodiversity. There is a very real threat to species, arising from the need to shift their ranges in the future to track regions
of suitable climate. The Important Bird Area (IBA) network is a series of sites designed to conserve avian diversity in the
face of current threats from factors such as habitat loss and fragmentation. However, in common with other networks, the IBA
network is based on the assumption that the climate will remain unchanged in the future. In this article, we provide a method
to simulate the occurrence of species of conservation concern in protected areas, which could be used as a first-step approach
to assess the potential impacts of climate change upon such species in protected areas. We use species-climate response surface
models to relate the occurrence of 12 biome-restricted African species to climate data at a coarse (quarter degree-degree
latitude-longitude) resolution and then intersect the grid model output with IBA outlines to simulate the occurrence of the
species in South African IBAs. Our results demonstrate that this relatively simple technique provides good simulations of
current species' occurrence in protected areas. We then use basic habitat data for IBAs along with habitat preference data
for the species to reduce over-prediction and further improve predictive ability. This approach can be used with future climate
change scenarios to highlight vulnerable species in IBAs in the future and allow practical recommendations to be made to enhance
the IBA network and minimize the predicted impacts of climate change. 相似文献
999.
Long-Term Variability in Bioassessments: A Twenty-Year Study from Two Northern California Streams 总被引:2,自引:2,他引:0
Long-term variability of bioassessments has not been well evaluated. We analyzed a 20-year data set (1984–2003) from four
sites in two northern California streams to examine the variability of bioassessment indices (two multivariate RIVPACS-type
O/E scores and one multimetric index of biotic integrity, IBI), as well as eight metrics. All sites were sampled in spring;
one site was also sampled in summer. Variability among years was high for most metrics (coefficients of variation, CVs ranging
from 16% to 246% in spring) but lower for indices (CVs of 22–26% for the IBI and 21–32% for O/E scores in spring), which resulted
in inconsistent assessments of biological condition. Variance components analysis showed that the time component explained
variability in all metrics and indices, ranging from 5% to 35% of total variance explained. The site component was large (i.e.,
>40%) for some metrics (e.g., EPT richness), but nearly absent from others (e.g., Diptera richness). Seasonal analysis at
one site showed that variability among seasons was small for some metrics or indices (e.g., Coleoptera richness), but large
for others (e.g., EPT richness, O/E scores). Climatic variables did not show consistent trends across all metrics, although
several were related to the El Ni?o Southern Oscillation Index at some sites. Bioassessments should incorporate temporal variability
during index calibration or include climatic variability as predictive variables to improve accuracy and precision. In addition,
these approaches may help managers anticipate alterations in reference streams caused by global climate change and high climatic
variability. 相似文献
1000.
Amit Garg R. C. Dhiman Sumana Bhattacharya P. R. Shukla 《Environmental management》2009,43(5):779-789
India has reasons to be concerned about climate change. Over 650 million people depend on climate-sensitive sectors, such
as rain-fed agriculture and forestry, for livelihood and over 973 million people are exposed to vector borne malarial parasites.
Projection of climatic factors indicates a wider exposure to malaria for the Indian population in the future. If precautionary
measures are not taken and development processes are not managed properly some developmental activities, such as hydro-electric
dams and irrigation canal systems, may also exacerbate breeding grounds for malaria. This article integrates climate change
and developmental variables in articulating a framework for integrated impact assessment and adaptation responses, with malaria
incidence in India as a case study. The climate change variables include temperature, rainfall, humidity, extreme events,
and other secondary variables. Development variables are income levels, institutional mechanisms to implement preventive measures,
infrastructure development that could promote malarial breeding grounds, and other policies. The case study indicates that
sustainable development variables may sometimes reduce the adverse impacts on the system due to climate change alone, while
it may sometimes also exacerbate these impacts if the development variables are not managed well and therefore they produce
a negative impact on the system. The study concludes that well crafted and well managed developmental policies could result
in enhanced resilience of communities and systems, and lower health impacts due to climate change. 相似文献