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51.
Makadia TH Adetutu EM Simons KL Jardine D Sheppard PJ Ball AS 《Journal of environmental management》2011,92(3):866-871
We investigated the possibility of re-using remediated soils for new bioremediation projects by spiking these soils with waste oil sludge in laboratory based microcosms. The level of Total Petroleum Hydrocarbon (TPH) reduction was high (>80%) in naturally attenuated microcosms and was not significantly improved by biostimulation, bioaugmentation and the combined treatment of bioaugmentation and biostimulation by week 12. This indicated that the observed TPH reduction might have been related to the soil's inherent hydrocarbon-degrading potential. Microbial community analysis (16S rDNA and ITS-based Denaturing Gradient Gel Electrophoresis fingerprints) confirmed the dominance of hydrocarbon degrading genera such as Alcanivorax and Scedosporium. Cluster and Shannon diversity analysis revealed similar but stable bacterial and fungal communities in naturally attenuated and amended microcosms indicating that rapid reduction in TPH may not always be accompanied by changes in soil microbial communities. This study has therefore shown that soils previously used for bioremediation can have an improved hydrocarbon degrading potential which was successfully re-harnessed for new projects. This ability to re-harness this potential is attractive because it substantially reduces operational costs as no additional bioremediation treatments are needed. It can also extend a landfill's lifespan as soils can be re-used again before landfill disposal. 相似文献
52.
ABSTRACT: A climate factor, CT, (T = 2–, 25-, and 100-year recurrence intervals) that delineates regional trends in small-basin flood frequency was derived using data from 71 long-term rainfall record sites. Values of CT at these sites were developed by a regression analysis that related rainfall-runoff model estimates of T-year floods to a sample set of 50 model calibrations. CT was regionalized via kriging to develop maps depicting its geographic variation for a large part of the United States east of the 105th meridian. Kriged estimates of CT and basin-runoff characteristics were used to compute regionalized T-year floods for 200 small drainage basins. Observed T-year flood estimates also were developed for these sites. Regionalized floods are shown to account for a large percentage of the variability in observed flood estimates with coefficients of determination ranging from 0.89 for 2-year floods to 0.82 for 100-year floods. The relative importance of the factors comprising regionalized flood estimates is evaluated in terms of scale (size of drainage area), basin-runoff characteristics (rainfall. runoff model parameters), and climate (CT). 相似文献
53.
江苏省耕地资源的发展趋势及潜力分析 总被引：2，自引：0，他引：2
根据《江苏统计年鉴(1998年)》,对江苏省耕地资源在数量、质量两方面的历年发展趋势进行了分析,并针对耕地资源存在的数量减少、质量恶化现状,对江苏耕地持续利用的潜力进行了探讨。 相似文献
54.
Species assessed as threatened by the International Union of Conservation of Nature (IUCN) show evidence of declining population sizes. Genetic diversity is lost by this decline, which reduces the adaptive potential of the species and increases its extinction risk in a changing environment. In this study, we collected an extensive dataset of nucleotide diversities in the COI (Cytochrome C Oxidase subunit I) mitochondrial gene for 4,363 animal species assessed by IUCN and found significantly reduced levels of diversity in threatened species of long-lived animal classes. Then, we built up a comparative frame by acquiring the 95% confidence interval (CI) of mean values of COI nucleotide diversity in bootstrapped samples of nonthreatened species. Finally, we tested the comparative frame with data from the endangered bivalve species, Pinna nobilis. We conclude that nucleotide diversity in COI is a good proxy for a first evaluation of the conservation status of species populations, where previous knowledge is lacking and census is difficult to perform . 相似文献
55.
《Journal of Environmental Planning and Management》2012,55(1):1-23
In our research we investigated the optimal utilization of land resources for agricultural production in Tabriz County, Iran. A GIS-based Multi Criteria Decision Making land suitability analysis was performed. Hereby, several suitability factors including soils, climatic conditions, and water availability were evaluated, based on expert knowledge from stakeholders at various levels. An Analytical Hierarchical Process was used to rank the various suitability factors and the resulting weights were used to construct the suitability map layers. In doing so, the derived weights were used, and subsequently land suitability maps for irrigated and dry-farm agriculture were created. Finally, a synthesized land suitability map was generated by combining these maps and by comparing the product with current land use SPOT 5 satellite images. The resulting suitability maps indicate the areas, in which the intensity of land use for agriculture should increase, decrease or remain unchanged. Our investigations have revealed that 65676 hectares may be suitable for irrigation and 120872 hectares may be suitable for dry-farm agriculture. This indicates a substantial potential to satisfy the significantly increasing regional demand for agricultural products. The results of our research have been provided to the regional authorities and will be used in strategic land use planning. 相似文献
56.
57.
针对目前测定水中氧化还原电位常用的铂电极直接测定法和去极化法,主要在方法原理、测定仪器、实验操作、准确度和测试时效等方面对这两种测定方法进行分析和比较研究。实验结果表明:直接法对于复杂介质样品测定时间长,测量不稳定且误差大;去极化法优点突出,对于复杂介质样品的测定时间较短,在保证数据准确的同时又提高了工作效率。 相似文献
58.
上海潜在滨海旅游资源调查及开发研究 总被引：1，自引：0，他引：1
上海市的海岸线蜿蜒460km，涉及5区1县，潜在滨海旅游资源亟待开发。为了更好地了解和掌握潜在上海滨海旅游资源的现状，结合上海独特的自然禀赋和社会经济条件，参照《旅游资源分类、调查与评价（国家标准）》（GB／T18972-2003），在对上海潜在滨海旅游资源普查的基础上，研究了上海潜在滨海旅游资源分类，分析了潜在滨海旅游资源特征和资源富集区状况，选划出上海应重点开发的6大潜在滨海旅游资源区，并分别就各资源区的开发对策与建议提出初步构想。 相似文献
59.
60.
湖北省油菜测土配方施肥下N2O减排潜力估算 总被引：1，自引：0，他引：1
以油菜种植大省-湖北省为案例地,在分析农田氮肥施用与油菜籽产量的基础上,依据氮肥利用率变化,估算测土配方施肥技术在湖北省全面推广的情况下,带来的N2O减排潜力.结果表明,在湖北省油菜种植中,测土配方施肥技术的推广将带来646.32ktCO2-eq的理论减排.以2012年湖北省油菜测土配方推广情况为基础,进一步全面实施该项技术,将产生173.91ktCO2-eq的减排量,占油菜种植因氮肥使用而产生的N2O排放总量的13.98%.测土配方施肥通过优化营养元素配比,提高油菜氮肥利用效率,是一项控制与减少农业N2O排放、减少氮素在环境中盈余量的有效措施. 相似文献