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71.
Two representative zones in Chongming Dongtan which faced the Yangtze River and East China Sea respectively were selected to study the variability of soil organic carbon (SOC) reservation capability between coastal wetland and riverside wetland in the Chongming Dongtan wetland as well as its mechanism by analyzing soil characteristics and plant biomass. The results showed the SOC content of riverside wetland was only 48.61% (P = 0.000 < 0.05) that of coastal wetland. As the organic matter inputs from plant litter of the coastal wetland and riverside wetland were approximately the same, the higher soil microbial respiration (SMR) of riverside wetland led to its lower SOC reservation capability. In the riverside wetland, the high soil microbial biomass, higher proportion of β-Proteobacteria, which have strong carbon metabolism activity and the existence of some specific aerobic heterotrophic bacteria such as Bacilli and uncultured Lactococcus, were the important reasons for the higher SMR compared to the coastal wetland. There were additional differences in soil physical and chemical characteristics between the coastal wetland and riverside wetlands. Path analysis of predominant bacteria and microbial biomass showed that soil salinity influenced β-Proteobacteria and microbial biomass most negatively among these physical and chemical factors. Therefore the low salinity of the riverside area was suitable for the growth of microorganisms, especially β-Proteobacteria and some specific bacteria, which led to the high SMR and low SOC reservation capability when compared to the coastal area.  相似文献   
72.
如何在国民经济发展计划中体现资源环境因素的影响?如何用现实可行的方法制定出符合可持续发展要求的国民经济发展计划?是目前环境经济领域急待解决的问题。本文从物质平衡的角度,探讨可持续经济发展计划的研究方法。  相似文献   
73.
通过构建知识创新能力与城市化、工业化进程的评价指标体系,对长三角地区2000-2011年25个地级以上城市的知识创新能力指数及城市化与工业化进程系数进行测算,并利用协调度模型综合分析评价了知识创新能力与城市化、工业化进程的协调关系.结果显示:①知识创新能力与城市化整体协调度优于其与工业化的协调度;②知识创新能力与城市化协调度逐步磨合到相对理想状态;③知识创新能力与工业化协调度呈现出先上升后下降又上升的较大波动性.  相似文献   
74.
The objective of this work is to examine to what degree the integration between R&D and environmental departments facilitates the achievement of an environmental practice-derived competitive advantage. With this aim, we surveyed 110 International Organization for Standardization (ISO) 14001 certified factories. The results reveal that the integration of environmental action into the R&D department enhances a company's reputation through the product quality and image. Moreover, the said integration positively influences the company's overall innovative capability and, hence, its ability to penetrate international markets.  相似文献   
75.
美洲商陆(Phytolacca americana)是一种我国广泛分布的商陆科入侵植物。通过实验观察和人工控制套袋等方法,对其开花动态、花部综合特征、繁育系统和种子萌发率等与繁殖相关的特性进行了研究,探讨了这些繁殖特性与入侵性的关系。结果表明,美洲商陆每年6—8月开花,单花序的花期为6~7 d,单花的花期为2~4 d。其花直径、雄蕊长、花柱长、柱头直径分别为(6.43±0.15)、(2.83±0.10)、(0.92±0.06)和(1.02±0.08) mm。套袋实验表明,美洲商陆自交亲和,自交结实率较高,为(93.33±1.92)%,而其同样存在异交结实现象,开花前去雄,不套袋,自然条件下其结实率为(42.22±2.22)%,其 P/O 值为372.37±31.24,杂交指数为3。综合套袋实验、P/O 值及杂交指数,表明其繁育系统为兼性自交,有时需要传粉者。主要访花昆虫为蜜蜂科(Apidae)、胡蜂科(Vespidae)、麻蝇科(Sarcophagidae)和食蚜蝇科(Syrphidae)昆虫。种子千粒质量为6.43 g,室内萌发率相对较低,但出苗整齐,寿命长。交配机制灵活、结实量大、种子寿命长、具有克隆繁殖等特性增强了美洲商陆的入侵性,是其入侵成功的重要因素。  相似文献   
76.
This article describes optimization strategy of SMCCM from perspective of utility of coal miner with the method of empirical research. Four elements of SMCCM are put forward which consist of “employee safety knowledge”, “equipment safety knowledge”, “environment safety knowledge” and “rule safety knowledge”. Eight elements of utility are put forward which consist of “benefit satisfaction”, “promotion satisfaction”, “job satisfaction”, “enterprise satisfaction”, “management satisfaction”, “colleague satisfaction”, “relationship satisfaction” and “communication satisfaction”. Then hypotheses of influence path between SMCCM and utility are proposed. JCIA is chosen as the sample to carry out survey, which questionnaire is designed based on the likert six-point scale to avoid the middle tendency of the test samples. Data analysis is done from following angles: analysis of the structure and utility of test samples, variables analysis of SMCCM and utility, model analysis of interaction between SMCCM and utility. And then results are obtained from the analysis of elements of SMCCM and elements of utility. Conclusions: first, “rule safety knowledge” should be strengthened above all; second, “job satisfaction” should be paid more attention to; third, coal miner’s benefit should be concerned specially.  相似文献   
77.
基于灰色层次分析法的突发事件应急管理能力评价   总被引:1,自引:0,他引:1  
突发事件的频发,使得对应急能力的评价备受关注。首先按照应急管理能力评价指标的选取原则,构建了突发事件应急管理能力评价指标体系。然后利用层次分析法确定各评价指标的权重系数,采用专家打分法建立评价指标集,运用灰色系统理论计算评分,进而建立了适用于突发事件应急管理能力的灰色层次分析评价模型。最后对某区域的突发事件应急管理能力进行实例分析,在定量计算的基础上,对其应急能力进行缺陷诊断,并提出措施建议,为完善应急能力提供科学有效的依据。  相似文献   
78.
Given the complexity and time-consuming of the conventional environmental capacity based assessment on air environment carrying capacity; a new method for assessing urban air environment carrying capacity based on air pollution index (API) is presented. By using this new method, the air environmental bearing capability of 333 cities at the prefecture level and above is assessed. The results show that of the 333 cities 9.6% is of high bearing capability, 34.5% relatively high bearing capability, 52.6% medium bearing capability, 2.7% low capability, and 0.6% is of weak bearing capability; in terms of regional distribution, the western region is of relatively high air environment bearing capability, followed by north-eastern and eastern regions, and the ambient air quality in the middle region is quite poor; among the 12 urban agglomerations in key regions, Pearl River delta, west side of Taiwan Strait and Chengdu-Chongqing agglomerations are of relatively high carrying capacity while other agglomerations are of medium bearing capability. The assessment results imply that the existing air quality standard (GB3095-1996) is quite unsound.  相似文献   
79.
煤矿安全管理能力理论框架研究   总被引:8,自引:2,他引:6  
运用文献分析和综合归纳等研究方法,对煤矿安全管理能力进行研究。通过研究得出:煤矿安全管理能力本质是一种累积专有知识的集合,是煤矿对由安全生产体系进行协调控制的过程中,诸要素相互作用形成的蕴含在煤矿内部的一种企业管理能力。具备知识属性的"人、设备、环境、制度"成为煤矿安全管理能力的构成要素,而"人的不安全行为"、"设备不安全状态"、"环境不安全条件"和"制度不安全条件"对构成要素产生不良影响,成为煤矿安全管理能力的影响因素。煤矿安全管理能力的构成要素与影响因素之间存在一种此消彼长的互动关系——构成要素越强则影响因素越弱,导致煤矿安全事故发生概率越低;构成要素越弱则影响因素越强,导致煤矿安全事故发生概率越高。  相似文献   
80.
通过分析近年来我国的公共安全形势和突发事件发生基本情况,预测未来5~10年各类突发事件的发展趋势,借鉴国外应急管理工作的特点和先进经验,总结分析我国应急体系与应急能力现状及存在的主要问题,提出提升我国应急体系和能力现代化建设水平的建议。  相似文献   
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