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991.
Use of Integrated Modeling to Enhance Estimates of Population Dynamics Obtained from Limited Data 总被引:2,自引:0,他引:2
MICHAEL SCHAUB†‡‡ OLIVIER GIMENEZ‡§ ANTOINE SIERRO† RAPHAËL ARLETTAZ† 《Conservation biology》2007,21(4):945-955
Abstract: Demographic data of rare and endangered species are often too sparse to estimate vital rates and population size with sufficient precision for understanding population growth and decline. Yet, the combination of different sources of demographic data into one statistical model holds promise. We applied Bayesian integrated population modeling to demographic data from a colony of the endangered greater horseshoe bats (Rhinolophus ferrumequinum) . Available data were the number of subadults and adults emerging from the colony roost at dusk, the number of newborns from 1991 to 2005, and recapture data of subadults and adults from 2004 and 2005. Survival rates did not differ between sexes, and demographic rates remained constant across time. The greater horseshoe bat is a long-lived species with high survival rates (first year: 0.49 [SD 0.06]; adults: 0.91 [SD 0.02]) and low fecundity (0.74 [SD 0.12]). The yearly average population growth was 4.4% (SD 0.1%) and there were 92 (SD 10) adults in the colony in year 2005. Had we analyzed each data set separately, we would not have been able to estimate fecundity, the estimates of survival would have been less precise, and the estimate of population growth biased. Our results demonstrate that integrated models are suitable for obtaining crucial demographic information from limited data. 相似文献
992.
海洋环境污染监测是海洋环境管理的“耳目”和“哨兵”.离开海洋环境污染监测.海洋环境管理将寸步难行。在过去15年中,中国海洋环境污染监测工作取得了长足的进步,集中表现在三个方面:一是形成了从国家海洋环境监测中心一海区监测中心-管区-监察站的四级海洋环境监测体系;组建了由国务院有关部委、沿海11个省(市)、自治区等有关部门100多个单位2500人参加的全国海洋环境污染监测网;每年获取各类海洋环境污染监测数据十万余个,提供了估计全国海洋环境形势的基础。二是海洋环境污染监测工作有中国的特色。组织上实行了优化布点、分级管理,初步形成了有特色的监测网络体系;技术上推行站点网络化、布点采样规范化、分析方法标准化、数据处理计算机化、质量保证工作系统化规范化,具有自己特色的技术路线正在形成;管理上逐渐走上科学管理的道路。三是为海洋环境管理服务的能力有了明显提高。该文概略地介绍了中国海洋环境污染监测工作的全貌,全面地总结了中国海洋环境15年来的十条宝贵经验,宏观地描述了未来中国海洋环境污染监测的发展方向。 相似文献
993.
以江阴市环境监测站标准化建设后评估工作为例,介绍了近年来苏南地区县级环境监测站的发展状况,指出了影响基层环境监测站发展的一些问题,并就相关对策进行探讨。 相似文献
994.
城市绿地降低空气中含菌量的生态效应研究 总被引:24,自引:0,他引:24
按照大气生物监测的方法和要求,选择了上海市区的交通干通。公园和居住区的主要类型的绿地,对绿地降低气挟菌数量的生态效应进行了初步研究,结果表明,绿地结构,植物种类配置和粉尘污染是影响绿地降低气挟菌数量效应的主要因素。 相似文献
995.
针对DASIBI 1000系列环境空气自动监测系统中常出现的一些故障进行了分析,并提出解决的方案和建议。 相似文献
996.
Xiaodong Zou Zhemin Shen Tao Yuan Shan Yin Jingping Cai Liping Chen Wenhua Wang 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):8068-8073
In this paper, a shifted power-law model, based on the wind profile model, had been supposed to simulate concentration gradient of nitrogen dioxide (NO2) with distance from a highway. Field experiments were performed for NO2 gradients from a highway in Shanghai by using passive samplers. The shifted power-law model was fitted well with experimental results of field experiments both in this study and in the literature. The results not only verified the validity of shifted power-law relationship between NO2 concentration and the distance from a highway, but also partially demonstrated that there were some significant similarities between wind profile and air pollutants concentration profile near highway. With known concentration of chosen reference point and appropriate value of the parameter k, the model could be practically applied for predicting the NO2 distributions near a highway. The methods of determining the parameter k were also discussed for further detailed studies. 相似文献
997.
结合工作实践,归纳了目前建设项目环保设施竣工验收监测报告中存在的几个突出问题,提出了完善竣工验收监测报告的几点建议。 相似文献
998.
Schmidt S 《Environmental science and pollution research international》2003,10(3):183-187
The efficiency of a water treatment program or a water monitoring program can be checked only if it is accompanied by water analysis procedures allowing meaningful statements on water quality. Meaningful statements do not only include high accuracy, but high precision as well. With high precision values, good repeatability and reproducibility is aimed for. Repeatability and reproducibility may either be monitored by regular inter-laboratory trials, without prescribing a distinct analytical method, or by applying a standardized method which has undergone thorough checks concerning its reliability and efficiency. The article presents the structure of the ISO, CEN and DIN standardization work in water analysis. 相似文献
999.
Zdenko Franić Gina Branica Branko Petrinec Gordana Marović 《Journal of environmental science and health. Part. B》2020,55(4):382-387
AbstractThis paper presents the results of long-term investigations of 137Cs activity concentrations in chicken meat and eggs from northwest Croatia for the period 1987–2018. The research has been done as a part of monitoring program of radioactive contamination in Croatia. The highest activity concentrations in both of these foodstuffs were measured in 1987 and have been decreasing exponentially ever since. The Fukushima-Daiichi accident in 2011 did not cause any increase of 137Cs activity concentrations. The ecological half-life for 137Cs was estimated to be 8.0 and 8.4?years for chicken meat and eggs respectively. The correlation between 137Cs in fallout and chicken meat as well as between 137Cs in fallout and eggs is very good, the respective correlation coefficients being 0.79 and 0.72, indicating that fallout was the main source of 137Cs contamination in both foodstuffs. The estimated effective doses received by adult members of the Croatian population due to the intake of radiocaesium by chicken meat and egg consumption for the overall observed period are very small, 2.0 and 0.6 µSv respectively. Therefore, chicken meat and chicken egg consumption was not a critical pathway for the transfer of radiocaesium to humans. 相似文献
1000.
有毒化学品销毁设施的环境保护 总被引:2,自引:0,他引:2
销毁有毒化学品时最重要的是确保人员安全与健康,以及生态环境安全。因此,其销毁活动必须遵守严格的安全与环保规定。介绍了有毒化学品销毁设施的安全与环境设计标准、控制工艺废弃物,尤其是有毒废气的具体做法,以及销毁设施内部、作业区附近的环境监测方案。这些环境保护措施同样也适用于其他有毒化学品销毁设施。 相似文献