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81.
我国臭氧短期暴露与人群死亡风险的Meta分析   总被引:4,自引:0,他引:4  
为评价中国臭氧短期暴露对人群死亡率的影响,获取臭氧污染与人群死亡的暴露-反应关系.检索了Pub Med、SCI(Science Ciation Index)、Ebsco、Ovid、中国生物医学文献数据库、维普中文科技期刊全文数据库、万方数据库和中国知网等,检索时间均为1990年1月1日至2014年12月31日,以"O3or ozone"、"mortality"、"China"、"臭氧"及"死亡"为关键词查找关于臭氧短期暴露对人群死亡率影响的文献.依据文献纳入和排除标准,进行文献筛选和质量评价.纳入文献后分别提取臭氧的暴露反应关系,采用Stata12.0软件进行Meta分析,根据异质性结果选择相应的效应模型合并效应值,并对结果进行敏感性分析、发表偏倚检验与校正.结果显示,大气中臭氧浓度每增加10μg·m-3,人群非意外总死亡率、心血管系统疾病和呼吸系统疾病死亡率分别增加0.40%(95%可信限(CI):0.303%~0.498%)、0.448%(95%CI:0.171%~0.724%)和0.461%(95%CI:0.225%~0.697%).与国外其它未纳入中国研究文献的Meta分析结果进行比较发现,中国的臭氧短期暴露对死亡风险影响的暴露-反应关系系数较高.大气中臭氧浓度的上升会导致我国人群非意外总死亡率、心血管系统疾病死亡率和呼吸系统疾病死亡率的增加.  相似文献   
82.
Urban forest ecosystems are complex and vulnerable social–ecological systems. The relationship between urban forests and housing is particularly variable and uncertain. We examine the influence of building renovation and rental housing on public trees at the parcel and street-section scale in a residential neighbourhood in Toronto, Canada. We use empirical data describing multiple tree inventories and government open data describing building permit applications to test for effects on urban forest structure, tree mortality, and tree planting. We found that the presence and number of building permits significantly predicted mortality at both scales, while planting was positively correlated with building permits at the street-section scale only. Multi-unit parcels had significantly lower rates of planting than single-unit parcels and multi-unit housing was positively correlated with mortality at the street-section scale. These findings suggest that where concentrated changes in housing stock are occurring, substantial losses of trees and associated ecosystem services are possible.  相似文献   
83.
Mortality of animals on roads is a critical threat to many wildlife populations and is poised to increase strongly because of ongoing and planned road construction. If these new roads cannot be avoided, effective mitigation measures will be necessary to stop biodiversity decline. Fencing along roads effectively reduces roadkill and is often used in combination with wildlife passages. Because fencing the entire road is not always possible due to financial constraints, high-frequency roadkill areas are often identified to inform the placement of fencing. We devised an adaptive fence-implementation plan to prioritize road sections for fencing. In this framework, areas along roads of high, moderate, and low levels of animal mortality (respectively, roadkill hotspots, warmspots, and coldspots) are identified at multiple scales (i.e., in circles of different diameters [200–2000 m] in which mortality frequency is measured). Fence deployment is based on the relationship between the amount of fencing being added to the road, starting with the strongest roadkill hotspots, and potential reduction in road mortality (displayed in mortality-reduction graphs). We applied our approach to empirical and simulated spatial patterns of wildlife–vehicle collisions. The scale used for analysis affected the number and spatial extent of roadkill hot-, warm-, and coldspots. At fine scales (e.g., 200 m), more hotspots were identified than at coarse scales (e.g., 2000 m), but combined the fine-scale hotspots covered less road and less fencing was needed to reduce road mortality. However, many short fences may be less effective in practice due to a fence-end effect (i.e., animals moving around the fence more easily), resulting in a trade-off between few long and many short fences, which we call the FLOMS (few-long-or-many-short) fences trade-off. Thresholds in the mortality-reduction graphs occurred for some roadkill patterns, but not for others. Thresholds may be useful to consider when determining road-mitigation targets. The existence of thresholds at multiple scales and the FLOMS trade-off have important implications for biodiversity conservation.  相似文献   
84.
Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is a serious pest of corn in several American countries. It is mainly controlled with synthetic insecticides. The objectives of this study were to evaluate the effects of the natural products, neem oil and pyroligneous extract, and the synthetic insecticide, lufenuron, at 2.50mL water (0.25 %) on the mortality of 2-, 4- and 6-day-old caterpillars of S. frugiperda, and their selectivities against fourth instar larvae of Eriopis connnexa Germar (Coleoptera: Coccinellidae). Four- and 6-day-old S. frugiperda caterpillars showed higher mortality after exposure to neem oil (83.33 ± 0.83 and 89.58 ± 0.90 %, respectively) and lufenuron (95.83 ± 0.96 and 85.41 ± 0.83 %), compared to pyroligneous extract (68.75 ± 0.69 and 31.25 ± 0.31 %). The deleterious effect of pyroligneous extract was higher in 2- (83.33 ± 0.83 % mortality) and 4-day-old (68.75 ± 0.69 %) S. frugiperda caterpillars than in 6-day-old caterpillars (31.25 ± 0.31 %). Larval mortality of the predator E. connexa was lower with neem oil and pyroligneous extract (25.00 ± 0.33 %) than with lufenuron (91.66 ± 1.22 %). Neem oil is thus recommended for control of S. frugiperda because of its high toxicity, combined with its relatively low toxicity to larvae of the natural enemy E. connexa.  相似文献   
85.
探讨不同臭氧度量指标对我国人群总死亡风险的影响.基于中国知网、万方数据库、维普中文服务平台、 Web of Science和PubMed数据库,检索了建库至2020年12月底发表的相关时间序列研究和病例交叉研究,最终纳入22项合格研究.按照臭氧每日1 h最大浓度(O3-M1h)、每日8 h最大平均浓度(O3-M8h)和每日24 h平均浓度(O3-24h)分别进行Meta分析.结果表明,O3-M1h指标(RR#, 1.005 2; 95%CI, 1.003 1~1.007 3)与人群总死亡风险增加的关联更加密切,O3-24h指标(RR#, 1.003 6; 95%CI, 1.002 5~1.004 8)和O3-M8h指标(RR#, 1.003 1; 95%CI, 1.002 2~1.004 1)关联较弱. 3类指标的亚组分析表明,冷季臭氧的总死亡风险更高,老年人(≥65岁)更容易受臭氧污染的影响,且北方地区总死亡风险高于南方地区.  相似文献   
86.
Globally, policies aiming for conservation of species, free-flowing rivers, and promotion of hydroelectricity as renewable energy and as a means to decarbonize energy systems generate trade-offs between protecting freshwater fauna and development of hydropower. Hydroelectric turbines put fish at risk of severe injury during passage. Therefore, comprehensive, reliable analyses of turbine-induced fish mortality are pivotal to support an informed debate on the sustainability of hydropower (i.e., how much a society is willing to pay in terms of costs incurred on rivers and their biota). We compiled and examined a comprehensive, global data set of turbine fish-mortality assessments involving >275,000 individual fish of 75 species to estimate mortality across turbine types and fish species. Average fish mortality from hydroelectric turbines was 22.3% (95% CI 17.5–26.7%) when accounting for common uncertainties related to empirical estimates (e.g., handling- or catch-related effects). Mortality estimates were highly variable among and within different turbine types, study methods, and taxa. Technical configurations of hydroelectric turbines that successfully reduce fish mortality and fish-protective hydropower operation as a global standard could balance the need for renewable energy with protection of fish biodiversity.  相似文献   
87.
The interactions between cod (Gadus morhua), herring (Clupea harengus) and sprat (Sprattus sprattus) in the Central Baltic Sea were examined with a simple dynamic model, an alternative to more complicated and data-demanding multispecies and ecosystem models. The main aims of the study were to compare the effect of alternative structures on the model output and examine the control relationships in the fish assemblage under different environmental conditions. The effect of environmental conditions was modelled using a stock-recruitment equation for cod incorporating an environmental index. The model output was especially sensitive to the functional response in predation by cod on herring and sprat. The type II functional response led to a collapse of the clupeid stocks when cod was abundant, while the type III response produced more realistic stock dynamics. According to the simulations, an abundant cod stock was able to keep the sprat stock at a low level, while the herring stock was less affected and benefited from the decreased density of sprat. Simulation of different fishing scenarios indicated that reducing fishing mortality to the level currently advised by ICES would allow the recovery of the cod stock even in unfavourable environmental conditions.  相似文献   
88.
89.
为了评估PM2.5排放导致女性生殖系统癌症的风险以及城乡差异,以卵巢癌为例,分析了中国东部地区2000~2011年期间PM2.5和卵巢癌发病率和死亡率的相关关系,并估算了PM2.5排放导致卵巢癌发病率和死亡率升高的风险.结果表明,城市地区卵巢癌发病率和死亡率显著高于农村,在城市地区,PM2.5与卵巢癌发病率显著相关,PM2.5年平均浓度每上升10μg/m3,城市地区卵巢癌发病率上升的相对风险为9.3%(相对于PM2.5年平均浓度为35μg/m3时),每十万人口升高0.51人.  相似文献   
90.
通过收集广州市2011~2015年6种疾病(非意外因素、心血管疾病、脑卒中、缺血性心脏病、呼吸系统疾病以及慢性阻塞性肺疾病)逐日死亡人数、逐日NO2浓度以及同期气象资料,采用广义相加模型探讨了NO2暴露对不同疾病死亡的影响(相对危险度,RR值)和累积滞后效应,并进一步采用分层分析方法解析了冷季(11月至次年4月)和暖季(5~10月) NO2死亡风险的差异.结果表明,NO2影响急促短暂,通常持续4d.当NO2浓度升高10μg/m3,在Lag0-4d时,人群非意外死亡人数将上升2.18%(RR=1.0218;95% CI:1.0167,1.0270),在冷季与暖季分别上升2.6%(RR=1.0260;95% CI:1.0191,1.0328)与0.57%(RR=1.0057;95% CI:0.9952,1.0163),两者差异有统计学意义(P=0.002).在不同疾病中,NO2对慢性阻塞性肺疾病的影响最大.因而NO2仍然为广州地区人群健康重要的危险因素,需要加强NO2排放的控制与治理,并且加强冷季健康风险预警以保护公共健康.  相似文献   
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