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961.
Knowledge and understanding about how the ecological systems of the Earth support life form the foundation for ecological literacy, which, in turn, is of critical importance for sustainability. There is widespread concern that levels of ecological literacy within many contemporary human societies are too low to enable effective decision-making about how to live sustainably. This paper presents and discusses the findings of an ecological literacy assessment of South Australian adults. The assessment tested for knowledge and understanding of ecological systems and interconnections with human society. Analyses revealed significant relationships between assessment scores and a range of value-based and behavioural characteristics. Such characteristics included the value placed on nature, time spent outdoors and in nature, involvement in nature-based activities, and perceived sources of ecological knowledge and understanding. Higher average scores were correlated with higher values accorded to involvement in outdoor activities, importance of the outdoors to enjoyment of life, importance of nature in the household, volunteer environmental activity and growing food. Higher scores were also correlated with higher education, research activities, outdoor lifestyles, place-based experiences, volunteer activities, mentors and colleagues, and books and magazines. Lower scores were achieved by those who considered media, natural disasters and environmental marketing to be major contributors to their ecological knowledge. These findings contribute to a broader study of the relationships between ecological literacy and a range of both socio-demographic and psychographic characteristics. They invite serious consideration from any society that values the participation of an informed population with the capacity to make sustainable environmental decisions.  相似文献   
962.
The atomised nature of the humanitarian system has led to frequent and repeated attempts to coordinate humanitarian activity. Since 2005, some of the best resourced, and arguably most successful, coordination mechanisms have been the humanitarian Clusters, groups of UN (United Nations) and non‐UN actors that engage in sectoral coordination of humanitarian response (such as the provision of healthcare and water) at the global and country level. Nevertheless, it is not clear exactly what ‘coordination’ means in the context of a Cluster. Formal guidance suggests that they should be aiming to create a single, joint strategy to guide the activities of members. Actual experience of the Clusters, however, indicates that looser forms of coordination are more effective. This finding resonates with organisational theory, and with the experience of emergency management professionals beyond the international humanitarian sector. To capitalise fully on the success of the Clusters, policymakers may need to rethink their attitudes to, and expectations of, coordination.  相似文献   
963.
为研究三峡水库春季水体营养盐与浮游植物的空间分布状况,于2013年3月对三峡水库22条支流及干流的6个断面进行采样监测. 结果表明:来水、回水、河口和干流4类断面ρ(TN)平均值分别为1.69、1.84、2.01、1.51 mg/L;ρ(TP)平均值分别为0.115、0.191、0.179和0.181 mg/L;不同类型断面间ρ(TN)、ρ(TP)差异不显著;水体中N、P的主要形态分别为NO3--N和PO43--P;N/P〔n(N)/n(P)〕从来水(110.8)至干流(18.9)逐渐降低. 三峡水库总体上为中营养状态,回水和河口区富营养化程度较高,富营养断面比例分别为45.4%和36.4%. 研究期间共检出浮游植物8门98属,其中以绿藻门、硅藻门和蓝藻门为主,分别检出42、26和17属;从组成上看,来水和干流断面以硅藻-绿藻为主,回水、河口断面以绿藻-硅藻为主. 浮游植物丰度由高到低依次为回水、河口、来水和干流断面. 调查期间,22条支流中有15条支流在不同位置发生水华,但主要集中在回水区;拟多甲藻水华为主要类型且集中在库区的下游支流,而库区中上游支流则以隐藻、衣藻、小球藻、小环藻等水华为主. 环境因子排序分析表明,在水华集中的回水-河口区域,影响浮游植物丰度分布的主要环境因子数明显少于其他区域,温度和ρ(DO)为该区域浮游植物丰度分布的主要影响因子,而ρ(TN)、ρ(TP)的影响不明显.   相似文献   
964.
Gas tracer tests can be used to determine gas flow patterns within landfills, quantify volatile contaminant residence time, and measure water within refuse. While gas chromatography (GC) has been traditionally used to analyze gas tracers in refuse, photoacoustic spectroscopy (PAS) might allow real-time measurements with reduced personnel costs and greater mobility and ease of use. Laboratory and field experiments were conducted to evaluate the efficacy of PAS for conducting gas tracer tests in landfills. Two tracer gases, difluoromethane (DFM) and sulfur hexafluoride (SF6), were measured with a commercial PAS instrument. Relative measurement errors were invariant with tracer concentration but influenced by background gas: errors were 1-3% in landfill gas but 4-5% in air. Two partitioning gas tracer tests were conducted in an aerobic landfill, and limits of detection (LODs) were 3-4 times larger for DFM with PAS versus GC due to temporal changes in background signals. While higher LODs can be compensated by injecting larger tracer mass, changes in background signals increased the uncertainty in measured water saturations by up to 25% over comparable GC methods. PAS has distinct advantages over GC with respect to personnel costs and ease of use, although for field applications GC analyses of select samples are recommended to quantify instrument interferences.  相似文献   
965.
Nickel-resistant bacteria isolated from underneath Ni-hyperaccumulators growing on serpentine soils were screened for production of polyhydroxyalkanoates. These rhizobacteria accumulated poly-3-hydroxybutyric acid [P(3HB)] accounting 3.9–67.7% of cell dry weight during growth in gluconate and/or glucose. Cupriavidus pauculus KPS 201 utilized only gluconate and accumulated about 67.7% P(3HB) while, Bacillus firmus AND 408 utilized both carbon sources for polymer synthesis. The isolates being resistant to Ni also accumulated substantial amount of P(3HB) when grown in presence of the heavy metal and this was revealed by transmission electron microscopic studies. Although B. firmus AND 408 produced only P(3HB) at higher concentrations of gluconate, C. pauculus KPS 201 synthesized copolymer of 3-hydroxybutyric acid (3HB) and 3-hydroxyvaleric acid (3HV) [P(3HB-co-3HV)]. In presence of 0.8% gluconate and 4 mM Ni, KPS 201 cells produced PHA amounting 81% CDW, which contained 76 and 24 mol% 3HB and 3HV monomers, respectively.  相似文献   
966.
Aquifer sediment and groundwater chemistry data from 15 Department of Defense facilities located throughout the United States were collected and analyzed with the goal of estimating the amount of natural organic carbon needed to initiate reductive dechlorination in groundwater systems. Aquifer sediments were analyzed for hydroxylamine and NaOH‐extractable organic carbon, yielding a probable underestimate of potentially bioavailable organic carbon (PBOC). Aquifer sediments were also analyzed for total organic carbon (TOC) using an elemental combustion analyzer, yielding a probable overestimate of bioavailable carbon. Concentrations of PBOC correlated linearly with TOC with a slope near one. However, concentrations of PBOC were consistently five to ten times lower than TOC. When mean concentrations of dissolved oxygen observed at each site were plotted versus PBOC, it showed that anoxic conditions were initiated at approximately 200 mg/kg of PBOC. Similarly, the accumulation of reductive dechlorination daughter products relative to parent compounds increased at a PBOC concentration of approximately 200 mg/kg. Concentrations of total hydrolysable amino acids (THAA) in sediments also increased at approximately 200 mg/kg, and bioassays showed that sediment CO2 production correlated positively with THAA. The results of this study provide an estimate for threshold amounts of bioavailable carbon present in aquifer sediments (approximately 200 mg/kg of PBOC; approximately 1,000 to 2,000 mg/kg of TOC) needed to support reductive dechlorination in groundwater systems. © 2012 Wiley Periodicals, Inc.  相似文献   
967.
This study evaluated the effect of heterogeneity in hydraulic conductivity on the tendency for contaminant plumes to attenuate via dilution, hydrodynamic dispersion, and molecular diffusion in simulated aquifers. Simulations included one homogeneous and four increasingly heterogeneous hydraulic conductivity fields. A numerical mass transport model generated an initial contaminant plume for each case; all initial plumes had the same mass. Next, the model simulated plume migrations through the simulated aquifers. Results suggest that highly heterogeneous settings are potentially effective at plume attenuation. Low‐velocity zones in heterogeneous settings delay plume travel, enabling more time for natural processes to lower contaminant concentrations in groundwater. © 2012 Wiley Periodicals, Inc.  相似文献   
968.
Rates of trichloroethene (TCE) mass transformed by naturally occurring biodegradation processes in a fractured rock aquifer underlying a former Naval Air Warfare Center (NAWC) site in West Trenton, New Jersey, were estimated. The methodology included (1) dividing the site into eight elements of equal size and vertically integrating observed concentrations of two daughter products of TCE biodegradation—cis‐dichloroethene (cis‐DCE) and chloride—using water chemistry data from a network of 88 observation wells; (2) summing the molar mass of cis‐DCE, the first biodegradation product of TCE, to provide a probable underestimate of reductive biodegradation of TCE, (3) summing the molar mass of chloride, the final product of chlorinated ethene degradation, to provide a probable overestimate of overall biodegradation. Finally, lower and higher estimates of aquifer porosities and groundwater residence times were used to estimate a range of overall transformation rates. The highest TCE transformation rates estimated using this procedure for the combined overburden and bedrock aquifers was 945 kg/yr, and the lowest was 37 kg/yr. However, hydrologic considerations suggest that approximately 100 to 500 kg/yr is the probable range for overall TCE transformation rates in this system. Estimated rates of TCE transformation were much higher in shallow overburden sediments (approximately 100 to 500 kg/yr) than in the deeper bedrock aquifer (approximately 20 to 0.15 kg/yr), which reflects the higher porosity and higher contaminant mass present in the overburden. By way of comparison, pump‐and‐treat operations at the NAWC site are estimated to have removed between 1,073 and 1,565 kg/yr of TCE between 1996 and 2009. © 2012 Wiley Periodicals, Inc.*  相似文献   
969.
A large-scale database concerning benthic copepods from the Arctic, Baltic Sea, North Sea, British Isles, Adriatic Sea and Crete was compiled to assess species richness, biodiversity, communities, ecological range size and biogeographical patterns. The Adriatic showed the highest evenness and the most species-rich communities. Assemblages from the North Sea, British Isles, Baltic and Crete had a lower evenness. The British Isles were characterised by impoverished communities. The ecological specificity of copepod species showed two diverging trends: higher specificity of species in more diverse assemblages was observed in the Adriatic, North Sea and Baltic. A uniformly high species specificity disregarding sample diversity was found on Crete and in the British Isles. Benthic copepod communities showed distinct patterns that clearly fit the predefined geographical regions. Communities were distinguishable and β-diversity was found to be high around Europe, indicating a high species turnover on the scale of this investigation. The British Isles and the North Sea were found to be faunistic links to the Baltic and the Arctic.  相似文献   
970.
Gagnon PR  Passmore HA  Platt WJ  Myers JA  Paine CE  Harms KE 《Ecology》2010,91(12):3481-6; discussion 3503-14
Pyrogenic plants dominate many fire-prone ecosystems. Their prevalence suggests some advantage to their enhanced flammability, but researchers have had difficulty tying pyrogenicity to individual-level advantages. Based on our review, we propose that enhanced flammability in fire-prone ecosystems should protect the belowground organs and nearby propagules of certain individual plants during fires. We base this hypothesis on five points: (1) organs and propagules by which many fire-adapted plants survive fires are vulnerable to elevated soil temperatures during fires; (2) the degree to which burning plant fuels heat the soil depends mainly on residence times of fires and on fuel location relative to the soil; (3) fires and fire effects are locally heterogeneous, meaning that individual plants can affect local soil heating via their fuels; (4) how a plant burns can thus affect its fitness; and (5) in many cases, natural selection in fire-prone habitats should therefore favor plants that burn rapidly and retain fuels off the ground. We predict an advantage of enhanced flammability for plants whose fuels influence local fire characteristics and whose regenerative tissues or propagules are affected by local variation in fires. Our "pyrogenicity as protection" hypothesis has the potential to apply to a range of life histories. We discuss implications for ecological and evolutionary theory and suggest considerations for testing the hypothesis.  相似文献   
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