Assessment of Effectiveness of Protection Strategies in Tanzania Based on a Decade of Survey Data for Large Herbivores

Abstract:  Considerable controversy surrounds the effectiveness of strictly protected areas that prohibit consumptive resource use. For Tanzania we compared temporal changes in densities of large herbivores among heavily protected national parks and game reserves, partially protected game-controlled areas, and areas with little or no protection. Comparisons based on surveys conducted in the late 1980s and early 1990s versus the late 1990s and early 2000s showed three consistent patterns across the country. First, significant declines in the densities of large herbivores between these two snapshots in time overwhelmingly outnumbered significant increases in all protection categories. Second, more species fared well (increased significantly or showed no significant change) in strictly protected national parks than in areas with partial or no protection and in heavily protected game reserves relative to areas with no protection. Third, significantly more species fared poorly (densities declined or were too low to detect a decline) than fared well in areas with partial or no protection. Our results show that although heavy protection was generally more effective in maintaining large herbivore populations than partial or no protection, continued long-term monitoring is needed in Tanzania to inform managers whether large herbivores are experiencing declining population trends even within heavily protected areas .     

Filling the Gaps in the Risks vs. Benefits of Mammalian Adult-Cell Cloning: Taking Bernard Rollin's Philosophy Its Next Step

A critique is made of Bernard Rollin's examination of the ethics of cloning adult mammalian cells. The primary concern is less to propound an anticloning or procloning position than to call for full exploration of the ethical complexities before a rush to judgment is made. Indeed, the ethical examination in question rushes toward an ethical position in such a way that does not appear consistent with Rollin's usual methodology. By extending this methodology – which entails full weighing of benefits and costs – it becomes apparent that there are real potential risks to this type of cloning in both animals and humans, besides the possible benefits, and that the scientific, political, philosophical, and broader academic communities should explore these risks and benefits extensively. Rollin's usual methodological call for hesitation before risks would translate into hesitation before the ethical risks of adult mammalian cell cloning instead of his paper's curiously laissez-faire stance.     

Trends and sources of particulate matter in the Superstition Wilderness using air trajectory and aerosol cluster analysis

Ambient aerosols adversely affect human health and visibility and impact climate. Identification of sources of particulate matter and its precursors is necessary for developing control strategies. The goal of this research is to utilize long-term speciated particulate matter data and back-trajectory cluster analyses to determine trends and sources of particulate matter in the Superstition Wilderness, a rural area east of Phoenix, Arizona. Twenty-four hour back-trajectories were calculated for every hour of every 24-h particulate matter sample obtained by IMPROVE from 1991 to 2004. Days that included back-trajectories with considerable spatial variance were excluded from further analyses. To minimize uncertainties inherent in single trajectories, all calculated trajectories for each sampling day were averaged to represent the air mass sampled during that day. Cluster analysis of trajectories identified four unique regions, including a region with Phoenix, a region with copper smelters, and one with coal-fired power plants. Yearly averages of sulfate, nitrate, soil, and carbon concentrations were calculated for each region. Statistically significant trends in species concentrations by region and independent of region and differences in concentrations between regions were examined.Sulfate concentrations from the region with smelters were higher than other regions but decreased during the study period. Emissions data from the smelters indicate that much of the sulfate from the region was due to the smelters. The overall 2.2% year⁻¹ decrease in sulfate concentrations at TNM is likely due to decreased emissions from the copper smelters. A 3.6% year⁻¹ increase in nitrate concentrations was driven largely by increasing NO_x concentrations from Phoenix and to a lesser extent the region southwest of the site which includes Tucson and suburban/urban areas between Phoenix and Tucson. Soil concentrations were higher from regions with deserts than the region without desert. This method could not identify trends or source regions of carbonaceous aerosols at this site.     

Concentrations and trends of benzene in ambient air over New York State during 1990–2003

Since 1990s, a systematic program to measure air toxics has been active in New York State with monitors located both in urban and rural areas. In this study we examined the spatial and temporal characteristics of benzene, a known human carcinogen that is emitted by many source categories. The analysis indicates that ambient concentration levels of benzene have decreased by as much as 60% over this period not only in the ozone non-attainment area of New York City that had the reformulated gas (RFG) requirements, but also over the rest of the state as well. Although the rate of decrease appears to have flattened out in recent years, the annual average concentration levels are found to be above the health risk threshold even at the remote location, Whiteface Mountain, suggesting the need for further reductions in benzene emissions.     

污水生物脱氮除磷工艺的现状与发展

阐述了污水生物脱氮除磷的机理,并按空间和时间顺序介绍了一些经典的脱氮除磷工艺,对其发展趋势作了展望。通过对除磷机理及工艺的介绍和分析,提出应加深对生物除磷机理的研究,从微生物的角度进行工艺调控。     

五常流域拉林河水环境现状、变化趋势及防治对策

本文运用单因子指数细致分析了五常流域拉林河水环境质量现状,运用秩相关系数定量研究9a的水环境污染变化趋势,明确提出了防治水污染的主要对策。     

Estimated trends and patterns of road traffic fatalities in China, 2002–2012

Objective: This study examined the time trends and age distribution patterns of estimated road traffic fatalities (RTFs) in China over the period 2002–2012. Methods: Data on age-, sex-, and region-specific RTF rates were provided by the Chinese Ministry of Health. The crude rates were standardized and the Mann-Kendall test was used to test the significance of time trends. Annual number of RTFs was calculated. To minimize the effect of yearly variations, magnitude of changes in and age distribution patterns of the RTFs were examined using mean values of 2 years. Results: RTFs increased significantly in China during the study period. Several features were identified for the RTFs in China. First, RTF rates skyrocketed in rural areas including towns and counties. Second, a significant increase in RTFs was also observed in cities even though the change in RTF rates was not statistically significant there. Third, individuals aged 20–24, 40–49, and 55–64, especially in rural areas, were particularly at risk for RTFs in recent years. Finally, RTFs became more common among middle-aged and older adults than young Chinese, with roughly 57% of all RTFs occurring among individuals aged 45 and above during 2011–2012. Conclusions: RTFs increased dramatically in China during the past decade, especially in rural areas. Age distribution patterns of RTFs have changed there. Community-based public health education and intervention programs are warranted.     

Effects of site-selection bias on estimates of biodiversity change

Estimates of biodiversity change are essential for the management and conservation of ecosystems. Accurate estimates rely on selecting representative sites, but monitoring often focuses on sites of special interest. How such site-selection biases influence estimates of biodiversity change is largely unknown. Site-selection bias potentially occurs across four major sources of biodiversity data, decreasing in likelihood from citizen science, museums, national park monitoring, and academic research. We defined site-selection bias as a preference for sites that are either densely populated (i.e., abundance bias) or species rich (i.e., richness bias). We simulated biodiversity change in a virtual landscape and tracked the observed biodiversity at a sampled site. The site was selected either randomly or with a site-selection bias. We used a simple spatially resolved, individual-based model to predict the movement or dispersal of individuals in and out of the chosen sampling site. Site-selection bias exaggerated estimates of biodiversity loss in sites selected with a bias by on average 300–400% compared with randomly selected sites. Based on our simulations, site-selection bias resulted in positive trends being estimated as negative trends: richness increase was estimated as 0.1 in randomly selected sites, whereas sites selected with a bias showed a richness change of −0.1 to −0.2 on average. Thus, site-selection bias may falsely indicate decreases in biodiversity. We varied sampling design and characteristics of the species and found that site-selection biases were strongest in short time series, for small grains, organisms with low dispersal ability, large regional species pools, and strong spatial aggregation. Based on these findings, to minimize site-selection bias, we recommend use of systematic site-selection schemes; maximizing sampling area; calculating biodiversity measures cumulatively across plots; and use of biodiversity measures that are less sensitive to rare species, such as the effective number of species. Awareness of the potential impact of site-selection bias is needed for biodiversity monitoring, the design of new studies on biodiversity change, and the interpretation of existing data.     

成都市冬季大气颗粒物组成特征及来源变化趋势

年冬季分别在成都市8个环境受体采样点采集PM₁₀、PM_2.5样品,同时采集颗粒物源类样品,分析上述样品质量浓度及多种无机元素、水溶性离子和碳组分的含量,以对这3 a冬季大气颗粒物浓度、特征组分、来源及变化趋势进行分析. 使用CMB-iteration模型对成都市中心城区的PM₁₀、PM_2.5进行来源解析. 结果表明: 成都市冬季ρ(PM₁₀)在工业区最高,PM_2.5污染呈现区域性特征;冬季PM₁₀的主要来源有扬尘、二次硫酸盐、煤烟尘、二次硝酸盐和机动车尾气尘,上述5类源在2010─2012年的分担率分别为24%～29%、17%～22%、13%～16%、6%～12%、6%～11%;对PM_2.5有重要贡献的源类有二次硫酸盐、扬尘、煤烟尘、二次硝酸盐和机动车尾气尘,这5类源在2010─2012年的分担率范围分别为25%～27%、19%～22%、12%～15%、11%～13%、8%～11%. 二次粒子、扬尘等是成都市大气颗粒物的主要污染源,其中扬尘、建筑水泥尘等以粗粒子为主的源类浓度贡献呈逐年下降趋势,而二次粒子等以细粒子为主的源类浓度贡献则逐年上升,成都市冬季大气细颗粒物污染加重.      

南汇边滩的沉积特征和沉积物输运趋势

在对南汇边滩沉积物粒度特征进行分析的基础上,利用Gao Collins泥沙概率输运模型探讨边滩的沉积物输运趋势,结果表明：①沉积物中值粒径、分选系数和偏度的分布具有一致性,三者相关性较强;②边滩的沉积物粒度特征表现为正偏,分选性较差,分选系数值集中在2左右,沉积物相对较粗（中值粒径大于0.01 mm）的区域主要集中在没冒沙中部、南汇咀及卢潮港近岸,其它区域沉积物相对较细（中值粒径小于0.01 mm）;③将 Gao Collins的泥沙概率模型和南汇边滩的动力与沉积环境结合表明,沉积物在东滩的净输运趋势是由北向南输运。由于南滩的动力条件相对复杂,因此南滩沉积物的净输运趋势有待进一步分析。