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781.
A sediment core collected from the sub-aqueous delta of the Yangtze River estuary was subjected to analyses of 137Cs and plutonium (Pu) isotopes. The 137Cs was measured using γ-spectrometry at the laboratories at the Nanjing University and Pu isotopes were determined with Accelerator Mass Spectrometry (AMS), measurements made at the Australian National University. The results show considerable structure in the depth concentration profiles of the 137Cs and 239+240Pu. The shape of the vertical 137Cs distribution in the sediment core was similar to that of the Pu. The maximum 137Cs and 239+240Pu concentrations were 16.21 ± 0.95 mBq/g and 0.716 ± 0.030 mBq/g, respectively, and appear at same depth. The average 240Pu/239Pu atom ratio was 0.238 ± 0.007 in the sediment core, slightly higher than the average global fallout value. The changes in the 240Pu/239Pu atom ratios in the sediment core indicate the presence of at least two different Pu sources, i.e., global fallout and another source, most likely close-in fallout from the Pacific Proving Grounds (PPG) in the Marshall Islands, and suggest the possibility that Pu isotopes are useful as a geochronological tool for coastal sediment studies. The 137Cs and 239+240Pu inventories were estimated to be 7100 ± 1200 Bq/m2 and 407 ± 27 Bq/m2, respectively. Approximately 40% of the 239+240Pu inventory originated from the PPG close-in fallout and about 50% has derived from land-origin global fallout transported to the estuary by the river. This study confirms that AMS is a useful tool to measure 240Pu/239Pu atom ratio and can provide valuable information on sedimentary processes in the coastal environment.  相似文献   
782.
Solid waste management (SWM) in many low- and middle-income countries is sometimes driven by the informal sector. Unfortunately, contributions of the sector to SWM are not acknowledged in many developing countries. This situation often arises from inadequate awareness and lack of advocacy for these development contributions. This article reports on the impact of a study conducted by final-year geography undergraduates on the informal waste management sector in Nsukka urban area, Nigeria. The purposes of this exercise were to stimulate development intervention on behalf of the sector to improve perceptions, attitudes and performance, to impart a range of development research skills and to expose the students to the business opportunities provided by SWM and recycling. Informal waste sector workers and government officials responsible for SWM were interviewed, and some commercial data on recycling operations were collected. Findings of this study indicate that such advocacy initiatives were effective in increasing students’ awareness of opportunities and interest in working in the informal waste sector to promote better SWM and development in Nigeria. Lessons from this university case study are also drawn for other developing countries struggling to achieve the poverty reduction and job creation Millennium Development Goals (MDGs).  相似文献   
783.
The World Bank used the Consumer Price Index (CPI) to calculate changes in the world poverty level (measured in U.S. dollars) prior to 1982. In 1983, the U.S. Bureau of Labor Statistics (BLS) replaced the CPI with several indices including CPI-W which was then adopted by the World Bank. This caused the inflated rate of the U.S. dollars and the percentage of the world population in poverty to be dramatically underestimated. This new incorrect procedure gives 25% (1.5 million) below the poverty line in 2005, while the more appropriate procedure (described herein) gives 52% (3.3 million in 2005). The rapid rise of the poverty line (using the preferable CPI) starting in 1987 occurred at nearly the same time as the peak in per capita annual cereal production.  相似文献   
784.
This paper analyses environmental and socio-economic barriers for plantation activities on local and regional level and investigates the potential for carbon finance to stimulate the increased rates of forest plantation on wasteland, i.e., degraded lands, in southern India. Building on multidisciplinary field work and results from the model GCOMAP, the aim is to (1) identify and characterize the barriers to plantation activities in four agro-ecological zones in the state of Karnataka and (2) investigate what would be required to overcome these barriers and enhance the plantation rate and productivity. The results show that a rehabilitation of the wasteland based on plantation activities is not only possible but also anticipated by the local population and would lead to positive environmental and socio-economic effects at a local level. However, in many cases, the establishment of plantation activities is hindered by a lack of financial resources, low land productivity and water scarcity. Based on the model used and the results from the field work, it can be concluded that certified emission reductions such as carbon credits or other compensatory systems may help to overcome the financial barrier; however, the price needs to be significantly increased if these measures are to have any large-scale impact.  相似文献   
785.
Rapid land-use change arising from incentives for afforestation has created tensions in rural communities previously dominated by agricultural enterprises. This paper reports on an innovative experiment with social learning that incorporated participatory modelling to resolve community concerns in a case study of plantation forestry in the Upper Clarence catchment of north-eastern NSW Australia. The development of a diagnostic framework helped identify socioeconomic and environmental issues within the community for investigation by a self-selected participatory advisory committee (PAC) representing a diversity of views. Implementation of a social learning exercise offered empathetic and intellectual engagement among PAC members that maintained interest, built confidence, and improved problem-solving capacity while fostering group ownership over decision making. A shared understanding of dynamic landscape problems helped empower participants to collaboratively develop solutions for improved management and operational practices, and cooperate to explore further options for plantation industry development under existing policy guidelines which are presented in this paper. As a result of frank discussions between diverse stakeholders in a mutually respectful learning environment that combined local, scientific and expert knowledge, concerns dissipated and participants developed a more favourable view of plantation forestry activity.  相似文献   
786.
Adaptive capacity in a community context has so far mainly been studied in developing countries as well as indigenous communities in the industrialised world. This article adds to that literature through reviewing studies undertaken in the Nordic countries and Russia, highlighting the ways in which general determinants of adaptive capacity play out in Northern, industrialised contexts. The paper illustrates that the determinants of adaptive capacity in industrialised states exhibit systematic differences from mixed subsistence-cash based communities such as those found in Arctic Canada. We discuss in particular the importance of economic resources in a market-based system, technological competition, and infrastructure, in determining adaptive capacity of natural resource-dependent communities in the Nordic countries and Russia. The paper also illustrates differences in adaptive capacity within the case study region, including between peripheral and central locations with regard to economic resources and diversification possibilities, and between Nordic and Russian cases with regard to infrastructure and technology access. The findings indicate that understanding of determinants of adaptive capacity in resource-dependent communities would benefit from both further contextualisation and broad comparison, across different types of political and administrative systems.  相似文献   
787.
Conference organizers are increasingly making efforts to reduce resource use at conferences, yet few responsibilities are placed on attendees. We hosted an ecology conference and offered attendees a discount if they took a sustainability pledge agreeing to reduce their resource use at the conference. In a post-conference survey, 83% of respondents reported fulfilling the pledge, but 62% indicated that convenience was the biggest obstacle impeding their ability to continue the pledge during and after the conference. We found great willingness by attendees to reduce resource use at and beyond our conference, and facilitating their participation was an important part of our success.  相似文献   
788.
Long-term (1860–2010) catchment mass balance calculations rely on models and assumptions which are sources of uncertainty in acidification assessments. In this article, we report on an application of MAGIC to model acidification at the four Swedish IM forested catchments that have been subject to differing degrees of acidification stress. Uncertainties in the modeled mass balances were mainly associated with the deposition scenario and assumptions about sulfate adsorption and soil mass. Estimated base cation (BC) release rates (weathering) varied in a relatively narrow range of 47–62 or 42–47 meq m−2 year−1, depending on assumptions made about soil cation exchange capacity and base saturation. By varying aluminum solubility or introducing a dynamic weathering feedback that allowed BC release to increase at more acidic pHs, a systematic effect on predicted changes in acid neutralizing capacity (ΔANC ca. 10–41 μeq l−1) and pH (ca. ΔpH = 0.1–0.6) at all sites was observed. More robust projections of future changes in pH and ANC are dependent on reducing uncertainties in BC release rates, the timing, and extent of natural acidification through BC uptake by plants, temporal changes in soil element pools, and fluxes of Al between compartments.  相似文献   
789.
The chemical composition of the odors typical of fires has recently been deciphered. Basically the constituents are mixtures of acetophenone, benzyl alcohol, hydroxylated derivatives of benzaldehyde, methoxylated and/or alkylated phenols and naphthalene. This finding makes it possible to develop objective, practical analytic measurement methods for the burnt smell as a contribution to improving fire damage assessment and remediation monitoring. With the aid of an artificially produced burnt smell and a panel of testers the odor detection threshold of a test mixture was determined olfactometrically to 2 μg m−3. Using a defined burnt-smell atmosphere in a test chamber, analytical methods with active sampling, the adsorbents XAD 7 and TENAX TA, and GC/MS measurement were then optimized and tested with a view to being able to carry out sensitive quantitative measurement of burnt smells. A further practical method with particular application to the qualitative characterization of this odor is based on the use of a new SPME (solid-phase microextraction) field sampler with DVB/CAR/PDMS (divinylbenzene/Carboxen™/polydimethylsiloxane) fibers.  相似文献   
790.
Indiscriminate use of agrochemicals worldwide, particularly, persistent organic pollutants (POPs), is of concern. Endosulfan, a POP, is used by various developing/developed nations and is known to adversely affect the development and the hormonal profiles of humans and animals. However, little is known about the molecular players/pathways underlying the adverse effects of endosulfan. We therefore analyzed the global gene expression changes and subsequent adverse effects of endosulfan using Drosophila. We used Drosophila melanogaster keeping in view of its well annotated genome and the wealth of genetic/molecular reagents available for this model organism. We exposed third instar larvae of D. melanogaster to endosulfan (2.0 μg mL−1) for 24 h and using microarray, we identified differential expression of 256 genes in exposed organisms compared to controls. These genes are associated with cellular processes such as development, stress and immune response and metabolism. Microarray results were validated through quantitative PCR and biochemical assay on a subset of genes/proteins. Taking cues from microarray data, we analyzed the effect of endosulfan on development, emergence and survival of the organism. In exposed organisms, we observed deformities in hind-legs, reminiscent of those observed in higher organisms exposed to endosulfan. In addition, we observed delayed and/or reduced emergence in exposed organisms when compared to their respective controls. Together, our studies not only highlight the adverse effects of endosulfan on the organism but also provide an insight into the possible genetic perturbations underlying these effects, which might have potential implications to higher organisms.  相似文献   
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