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41.
基于Meta分析的矿业城市生态服务价值转移研究   总被引:2,自引:0,他引:2  
采矿活动剧烈干扰了区域土地利用,对生态系统健康造成了严重影响。论文在综合国内若干资源型城市生态系统服务价值研究实例的基础上,提炼系列指标参数,运用Meta分析方法建立并验证了专门针对矿业城市耕地、林地、草地、水域的价值转移模型,并以河北省武安市为例估算了1987、2001和2014年的生态系统服务价值。研究结果表明:1)价值转移模型可以有效地评估矿业城市生态系统服务价值;2)武安市生态系统服务总价值呈现先增后减的趋势,2001年之后呈现快速下降状态;3)从地类面积来看,1987—2014年间武安市经济发展对生态用地产生的干扰程度为:耕地>草地>水域>林地,从服务价值角度看,干扰程度为:耕地>水域>草地>林地;4)在生态用地总面积减少的情况下,适当优化生态用地土地利用结构可以提高生态系统服务总价值。  相似文献   
42.
To investigate short-term effects of ambient ozone exposure on mortality in Chinese cities, we conducted a meta-analysis of 10 effect estimates of 5 short-term studies, which reported associations between ambient ozone and mortality in Chinese mainland cities. And we estimated pooled effects by non-accidental mortality, cardiovascular mortality, and respiratory mortality. Combined estimates and their 95%CI were tested by RevMan 5, and Funnel plots were used for the bias analysis. For a 10 μg m−3 increase of maximum 8-h average concentration of ozone, the percent change for non-accidental mortality, cardiovascular mortality, and respiratory mortality were 0.42 (95%CI, 0.32–0.52%), 0.44% (95%CI, 0.17–0.70%) and 0.50% (95%CI, 0.22–0.77%), respectively. Compared with pooled estimates from other meta-analyses on ambient ozone-associated mortality, our pooled estimate for non-accidental mortality was slightly higher than previous ones and pooled estimate for cardiovascular mortality was consistent with others. However, we observed significantly positive association between ambient ozone and respiratory mortality, which were generally nonsignificant in earlier studies. By combining estimates from published evidence, a small but substantial association between ambient ozone level and mortality was observed in Mainland China.  相似文献   
43.
Sperm competition (the competition among the sperm of different males for fertilization of the eggs of a female) has been suggested to be an important component of sexual selection, but no general assessment has been made of this proposition. We used a meta-analytic approach to assess the extensive literature on paternity (the proportion of offspring in a focal nest sired by an attending male) in birds based on allozyme and molecular techniques. The relative variance in male mating success was on average increased by a factor of 4.6 over the variance in apparent male success. Males with more extravagant secondary sexual characters had higher paternity in their own nests than less adorned males. There was a weak effect of male age being positively associated with paternity in own nests. Male body size measured as the length of wing and tarsus was weakly positively associated with paternity in own nests. Male survival prospect was positively associated with paternity in own nests. Polygynous males generally had decreased paternity of their broods compared to monogamous males. Paternity of the resident male decreased with increasing population density and breeding asynchrony. The intensity of paternity guards such as within-pair copulation rate and mate guarding were not significantly related to extra-pair paternity. Sperm competition was thus an important component of sexual selection by increasing the variance in male mating success, and by being associated with the expression of secondary sexual characters, in particular in dense and asynchronously breeding populations of birds. Received: 12 February 1998 / Accepted after revision: 31 May 1998  相似文献   
44.
To investigate the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts of the workers, domestic and foreign published research data on the change of human peripheral blood leukocyte counts under low-level occupational benzene exposure from January 1990 to December 2020 were collected and analyzed. According to the literature inclusion and exclusion criteria, 18 independent studies from 12 publications were selected for meta-analysis to explore the effect ...  相似文献   
45.
Introduction: The purpose of this review was to identify the most influential personality predictors of speeding. Method: Thus, this study analyzed the associations of Anger-Aggression and Impulsive-Sensation Seeking with Speeding. Research studies included in online databases and papers identified in previous reviews were considered for inclusion. Results: Using a random effects model, we found a small but significant effect for the relation between Anger-Aggression and Speeding (r = 0.12 [0.06–0.18], Z = 3.85, p < 0.001). We identified a significantly stronger effect for the relation between Impulsive-Sensation Seeking and Speeding, but still of low magnitude (r = 0.23 [0.16–0.29], Z = 6.54, p < 0.001). Moderator analysis revealed only one significant moderator: driver type. Namely, for professional drivers, the relation with Speeding was non-significant for both predictors (r = −0.004, p = 0.958 for Impulsive-Sensation Seeking and r = 0.02, p = 0.720 for Anger-Aggression, respectively) and significantly smaller than the associations for general population and young drivers. Conclusions: Overall, our results confirm Speeding’s associations with both hypothesized most important predictors, but at a low magnitude.  相似文献   
46.
基于Meta分析的中国水资源价值移位研究   总被引:1,自引:1,他引:0       下载免费PDF全文
Meta分析价值移位方法是国际上资源价值评价领域关注的热点,国内相关研究较少。水作为重要的自然资源,研究其价值是解决我国水资源问题的关键途径。本文搜集我国水资源价值评估实证研究结果,建立效益移位基础数据库,应用基于Meta分析的函数效益移位方法,对我国水资源价值移位做实证研究,探讨效益移位法在我国水资源价值评估领域的可应用性及发展前景。结果表明:①水资源所在地、人口密度、水质、供水成本和利润以及对最大水费承受程度的差异会影响地区水资源价值变化;②模型平均移位误差在可接受范围内,可用于快速评估地区水资源价值;③省级层面水资源价值呈现出沿海高于内陆,华北、华东和西南高于其他地区的空间分异 规律。  相似文献   
47.
This paper reports a meta-analysis of studies using the New Environmental Paradigm (NEP) Scale over the last 30 years. A review of 69 studies from 36 countries (including 58,279 participants from 139 samples) shows that there is considerable variation in the way the NEP Scale is used, particularly with regards to the number of items used and the number of points on the Likert scale employed. Results from weighted regression analyses reveals that variations in sample type and scale length have a significant effect on NEP scores. In particular, environmentalist and white-collar samples scored significantly higher on the NEP Scale than nationally or regionally representative samples, while blue-collar samples scored significantly lower; and participants scored higher on 6-item versions of the scale than on the revised 15-item version, and lower on versions of the scale containing 5, 7, 8 or 10 items. Implications of this research for the comparability of previous studies using the NEP Scale are discussed and guidelines for future research are presented.  相似文献   
48.
Neal R. Haddaway 《Ambio》2014,43(5):703-706
Much of the scientific literature in existence today is based on model systems and case studies, which help to split research into manageable blocks. The impact of this research can be greatly increased in meta-analyses that combine individual studies published over time to identify patterns across studies; patterns that may go undetected by smaller studies and that may not be the main subject of investigation. However, many potentially useful studies fail to provide sufficient data (typically means, true sample sizes, and measures of variability) to permit meta-analysis. Authors of primary research studies should provide these summary statistics as a minimum, and editors should require them to do so. By putting policies in place that require these summary statistics to be included, or even those that require raw data, editors and authors can maximize the legacy and impact of the research they publish beyond that of their initial target audience.  相似文献   
49.
施肥对农田土壤抗生素抗性基因影响的整合分析   总被引:2,自引:1,他引:1  
冉继伟  肖琼  黄敏  蔡岸冬  张文菊 《环境科学》2022,43(3):1688-1696
探讨施肥措施对农田土壤中抗生素抗性基因(ARGs)的影响,为了解和掌握农田土壤中ARGs的来源与积累特征,制定保障生态环境安全和人类健康的管理策略提供科学依据.通过收集近20年(2000~2020年)来已发表的文献,获得独立实验条件下农田土壤ARGs数量和相对丰度匹配数据215组和201组.结果表明,与不施肥相比,配施...  相似文献   
50.
In the last few years there has been a growing interest in transport policy concerning behaviour oriented ‘soft’ measures to reduce private car use. Besides an assessment of the methodological quality of available evaluation results, the present paper focuses on a quantitative, meta-analytical synthesis of this empirical evidence. For these purposes a data set of 141 studies evaluating three types of soft transport policy measures was compiled mainly from already published narrative research reviews. The ability to draw strong causal inferences from the available research evidence is limited by the fact that all the retrieved evaluation studies use weak quasi-experimental designs. At least for one policy measure type our analyses also indicate the presence of a reporting bias. Across all three soft policy measures we found a statistically significant random-effects pooled effect size of 0.15. Translated into the original metric such an effect size indicates an increase in the no-car use proportion from 39% to 46%.  相似文献   
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