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381.
本文用两种不同日夜分界限统计了成都、重庆的P-T大气稳定度频率。结果表明,两种分界统计大气稳定度频率,不稳定类完全相同;以h=0分界比以h=k_1分界中性频率增加,稳定频率减少,两者频率差值大小与地理位置、气候和天气特征有关;这与理论分析完全符合。通过对比指出,h=0分界的应用有局限性。同时,通过计算表明,实际工作中,太阳赤纬σ每十日取一概略值已足够精确了。 相似文献
382.
古湖岸堤是湖泊湖面变化的地貌学证据,通过古湖岸堤沉积年代学研究可重建地质时期湖泊演化历史。青藏高原内陆湖泊众多,保存了大量的第四纪时期古湖岸堤,是研究过去湖泊演化和气候变化信息的重要载体。对青藏高原班戈错盐湖北岸和东岸的低位连续古湖岸堤开展了地貌调查和光释光年代学研究。结果表明班戈错自末次冰消期(13. 5±1. 2 ka BP)以来,湖面整体呈波动下降过程,期间出现了4期湖面稳定阶段,分别在末次冰消期(13. 5±1. 2~11. 2±1. 0 ka BP)、全新世早中期(10. 1±0. 8~6. 5±0. 5 ka BP)、全新世后期(4. 2±0. 4~3. 1±0. 2 ka BP)以及全新世晚期(1. 7±0. 1~1. 2±0. 1 ka BP)。全新世晚期约1. 7 ka BP以后湖面迅速退缩,湖泊蒸发浓缩进入盐湖阶段。在末次冰消期班戈错高湖面形成主要与北半球太阳辐射强度增加引起气温升高,导致区域冰雪融水量增加相关,而在全新世湖面变化主要受印度季风强度变化控制。 相似文献
383.
Assessments of pesticide impacts globally and holistic policies to address them require accurate pesticide use data, but good use data are difficult to find. For comparable estimates across countries, researchers and policymakers depend upon pesticide use data collected by the UN Food and Agriculture Organization (FAO). We analyze the FAO database and find declines in data reporting and data quality since 2007. We present a novel method that uses bilateral paired mirror trade statistics and an index of reporter reliability to add, update and/or replace data for 137 countries. The resulting Global Pesticide Use and Trade (GloPUT) database shows pesticide use in low and lower-middle income countries has been substantially underestimated. Over the last decade, global pesticide use grew 20% by volume; use in low-income countries grew by 153% over the same period. GloPUT estimates more accurately reflect social science findings on recent agrichemical supply chain restructuring and agrarian development, which indicate substantial increases in pesticide use. Significant issues with data reporting and quality mean that the impacts of recent changes in pesticide production, availability and adoption were not reflected in the FAO database, and, as a result, neither are they reflected in high profile environmental assessments. 相似文献
384.
Environmental concern is crucial as bottom-up support for policies that aim to tackle the multiple ecological crises. This paper investigates which characteristics of 206 European regions are robust drivers of generalized environmental concern. To this end, 25 Eurobarometer survey waves between 2009 and 2019 were combined with measures of the regional economy, population, geography, environmental quality, and meteorological events. Bayesian model averaging is used to systematically account for model uncertainty in the estimation of partial correlations. The results indicate that environmental concern increases with income level, a more equal distribution of income and wealth, and a less greenhouse gas-intensive industrial sector. Furthermore, regions with younger and better educated populations exhibit higher levels of environmental concern. In terms of environmental characteristics, both geographical vulnerability to natural hazards and meteorological events affect environmental concern. The results highlight the importance of the socio-economic and environmental context of opinion formation and have implications for designing and communicating environmental policies. 相似文献
385.
Coastal erosion management is primarily based on economic considerations (cost-benefit analysis). From the perspective of social justice (as a particular expression of the wider concept of human rights), however, several arguments can be advanced regarding public intervention in coastal defence management when private property is threatened by coastal erosion. In this paper we examine these arguments at both the short-term local scale and the long-term large spatial scale and consider the merits of inclusion of a social justice dimension in coastal erosion management. The coast provides a range of resources that benefit society as a whole. Coastal residents and property owners face a direct financial loss from coastal erosion but the general public also stands to incur losses other than purely financial if it there is public intervention for the benefit of these property owners. The arguments for public intervention are strongest at the local and short-term scales but they weaken (and even reverse) at geographically larger and longer time scales. At larger scales, the costs to society increase as intergenerational equity, non-coastal residents, climate and sea level change, and the environment are considered. Because of the intensity of interest involved at the local level, we argue that the necessary hard decisions must be made nationally if a sustainable policy is to be adopted. Social justice considerations provide a potential improvement on the traditional economic cost/benefit-based decision-making process of coastal erosion management but they only contribute to sustainability if viewed at the national level. 相似文献
386.
This paper outlines mining aspect of view to reclamation studies based on rather simpler but more practical analyses in terms
of legislations and regulations in Turkey. This paper also presents the results of various multi-disciplinary experimental
studies aimed at the development of a reclamation proposal for an open pit mine located in the Istanbul Agacli region. Within
the scope of this study, the current conditions and environmental features of the working area and its surrounding were evaluated.
Various experimental studies were carried out on the representative samples taken from the overburden material and water sources
in order to detect the existence of any contamination and also to determine the properties of samples subjected to the reclamation.
Then, both environmental features and the results of experimental studies of the working area were evaluated. At the end of
the evaluation, a simple and practicable reclamation proposal was developed. 相似文献
387.
The study of brine aquifers in southern Taiwan is highly complicated by hybrid geochemical reactions, which obscure important
geochemical information. Using multivariate analysis on major and minor ion compositions normalized by Cl− content, chemical constituents were combined into two principal components representing brine mixing and mineral precipitation.
Comparing to multivariate analysis on the original data, this procedure reveals more geochemical information. It demonstrates
that the brine groundwater of the region is primarily composed of highly evaporated seawater. The evaporation ratio is >70%;
a point at which calcite, dolomite and gypsum precipitate. Oxygen and hydrogen isotopic compositions confirm this inference;
and further, geochemical modeling quantitatively determined the evaporation ratio to be about 85%. Natural boron contamination
is a consequence of brine groundwater. Two evolutionary trends in the plotting of the Cl/B ratio versus Cl− can be identified: (1) Cl/B ratio decreases with boron being released from clay minerals when brine aquifers are flushed
with freshwater; and (2) Cl/B ratio increases when seawater of a high Cl/B ratio infiltrates coastal aquifers. 相似文献
388.
The interface between environmentalism and neoliberalism in industrialised nations is dynamic and evolving with each of these significant socio-political movements exerting influence on the other. In the context of Australian environmental policy, ideas of heritage, sense of place and belonging are increasingly invoked to support the current policy emphasis on the role of regional communities for realising goals for land and water conservation and environmental restoration. To explore the broader meaning and consequences of these developments, we focus on the manner in which ideas of heritage are employed and evoked within the Murray–Darling Outreach Project, a collaboration between the Murray–Darling Basin Commission, a key natural resource management agency, and the National Museum of Australia. The Murray–Darling Outreach Project has the aim of increasing community involvement in local environmental issues by promoting ideas of vernacular heritage. 相似文献
389.
The use of temporal mixture analysis (TMA) for creating a long-term baseline, or environmental “normal” is described. TMA is a promising analysis method derived from the hyperspectral image processing technique of spectral mixture analysis (SMA). TMA is algebraically identical to SMA, except that it is applied to temporal spectra rather than to electromagnetic spectra. TMA has particular potential to extract climate signals from long image sequences. 相似文献
390.
Douglas E. Booth 《社会与自然资源》2017,30(11):1404-1420
Postmaterialist theory suggests that under conditions of continuously expanding economic and personal security, younger generations will be less oriented to acquiring material goods and more committed than their older peers to attaining postmaterial social goals such as increased free self-expression and a healthy natural environment. Using the latest World Values Survey sample for the United States, ordinary least squares (OLS) and logit regressions are employed to test whether youth is a predictor of postmaterialism as theory suggests, and whether postmaterialism positively predicts environmental concern and individual actions in support of the environment. Age is found to be a negative and statistically significant factor in explaining variation in the postmaterialism index, and this index is in turn found to be a statistically significant positive factor in explaining individual environmental concern and activism. A combination of increased economic security and entrance of younger generations into adulthood could well matter for our environmental future. 相似文献