苯并[a]芘对马氏珠母贝D型面盘幼虫发育的影响

苯并芘(B[a]P)已广泛分布于海洋环境中,低等海洋无脊椎动物从受精卵开始整个生长发育过程都面临着B[a]P等多环芳烃类污染物(PAHs)的威胁。本实验以热带海洋优势贝类马氏珠母贝(Pinctada maetensii)作为材料,研究B[a]P对马氏珠母贝D型面盘幼虫发育的影响。将幼虫暴露于不同浓度(1、2、4、10和15μg·L-1)B[a]P中,在暴露后第12、24、36、48、72、84小时,分别测定其D型面盘幼虫的死亡率和畸形数。结果表明:B[a]P对D型面盘幼虫死亡率的影响明显,死亡率与时间呈正相关,其中4和10μg·L-1浓度组的响应最敏感。在1～10μg·L-1浓度范围内,死亡率与浓度呈正相关;B[a]P暴露对马氏珠母贝D型面盘幼虫的形态也有显著影响,且随着浓度的增大产生畸形个体的时间越短。另外,B[a]P对马氏珠母贝D型面盘幼虫的半数致死浓度(LC50)随着时间的推移逐渐降低后趋于稳定,48h时LC50趋于稳定,为21.56μg·L-1。研究表明,B[a]P对马氏珠母贝D形幼虫的发育具有不利影响,并可能影响其种群结构。     

The dynamics of heavy metals in plant-soil interactions

The effects of soil contamination by heavy metals are studied by a mathematical interaction model, validated by experimental results. The model relates the dynamics of uptake of heavy metals from soil to plants. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality. Data are taken from soil with Cd, Cu and Zn treatments for alfalfa, lettuce, radish and Thlaspi caerulescens, measuring the concentrations in the aboveground biomass of plants. At low concentrations, the effects of heavy metals are moderate, and the dynamics seem to be linear. However, increasing concentrations exhibit nonlinear behaviors.     

长江口溯河鳗苗开发率估算

利用长江口南支上段东风西沙调查站位(121°15′45′′E;31°40′18′′N)2015年度鳗苗捕捞数据,通过CPUE波动趋势分析,确定当年日本鳗鲡鳗苗溯河汛期特征;进而采用Leslie和Delury两种方法估算东风西沙站位鳗苗资源指标。结果显示,2015年度东风西沙站位出现6个明显的鳗苗补充汛期,两种方法估算的汛期波动规律一致。各汛期捕捞持续时间5~27 d,平均为10.17 d。Leslie法估算的各汛期捕捞开发率43.38%~96.30%,平均77.14%;Delury法估算结果为43.36%~105.37%,平均81.43%;均为较高水平。高开发率表明东风西沙水域樯张网作业方式致使溯河迁移鳗苗处于高度开发状态,减少溯河鳗苗数量,影响长江流域成鳗资源。Leslie法估算日捕捞死亡系数和日捕捞死亡率平均值分别为0.23和20.02%,均分别低于De Lury法估算平均值0.27和22.79%;捕捞死亡系数将为采用年渔获量估算鳗苗资源量提供基础数据。     

Risk factors for mortality during the 2002 landslides in Chuuk, Federated States of Micronesia

This study examines health effects resulting from landslides in Chuuk during Tropical Storm Chata'an in July 2002, and suggests strategies to prevent future mortality. In August 2002, we conducted a cross-sectional survey to identify risk factors for mortality during landslides, which included 52 survivors and 40 surrogates for 43 decedents to identify risk factors for death. Findings suggest that 1) females had a higher mortality rate from this event than males, and 2) children aged 5–14 years had a 10-fold increase in mortality when compared with annual mortality rates from all causes. Awareness of landslides occurring elsewhere and knowledge of natural warning signs were significantly associated with lower risks of death; being outside during landslides was not associated with reduced mortality. In Chuuk, improving communication systems during tropical storms and increasing knowledge of natural warnings can reduce the risk for mortality during landslides.     

Seagrass mortality due to oversedimentation: an experimental approach

Mortality due to oversedimentation of the Mediterranean seagrassPosidonia oceanica was experimentally evaluated by field manipulations of the sediment level. Increased levels of sediment placed over plant shoots and rhizomes induced significant shoot mortality, even at moderate burial levels (ca. 5 cm). When sediment was added to reach levels 15 cm higher than the initial one, a 100 % mortality was observed after 200–300 days. The response of the plant was independent of site and depth. These results can be used in ecological risk assessment of coastal activities which potentially affect sediment deposition.     

PM2.5污染对我国健康负担和经济损失的影响

开展全国范围归因于PM_2.5污染的健康负担和经济损失研究,对于污染防控政策至关重要.首先利用空气质量模型（WRF-Chem）模拟结果,分析2016年PM_2.5的时空分布和暴露水平;同时结合环境健康风险及环境价值评估方法,评估PM_2.5污染引起的健康负担和经济损失;最后基于情景分析方法,预估实现具体PM_2.5控制目标的健康经济效益.结果表明,2016年,我国PM_2.5污染主要集中在京津冀及周边地区、长三角地区、四川盆地以及西北沙漠地区,且71.49%的人口暴露在PM_2.5浓度高于35 μg·m^-3的环境空气中;PM_2.5污染造成约106.04万人过早死亡,约占总死亡人数的10.9%,其中冠心病和中风约占80%;PM_2.5污染造成健康经济损失7059.31亿元,约占国内生产总值（GDP）的0.95%.PM_2.5污染造成的健康负担和经济损失存在显著空间差异,主要分布在PM_2.5浓度和人口密度高的中东部地区;情景分析表明,我国所有地区PM_2.5浓度降至35 μg·m^-3,只能避免17.11%的健康经济损失,而降至10 μg·m^-3可以带来80.47%的健康经济效益.建议环境管理者进一步加强控制力度,更好地保障居民的健康和财富利益,尤其是心脑血管疾病患者等敏感人群以及归因死亡率高的地区.     

大鼠胚胎期PFOS暴露致出生早期死亡及神经系统发育影响的基因组学分析

为了阐明PFOS导致新生儿死亡的可能原因和机制,探讨PFOS致死与神经系统发育的相互联系,利用基因芯片技术,观察了经PFOS饲料染毒后出生1和7d大鼠脑组织基因表达情况,通过基因组学(Gene Ontology)和生物路径(Pathway)对差异基因的功能和相互联系进行分析.结果显示,PFOS染毒后,出生1、7d的大鼠脑皮质组织分别有864、642条基因发生差异表达,差异基因涉及的与PFOS致死相关的生物过程包括中枢神经系统发育、血循环系统、刺激应答、骨骼发育、氧化应激、心脏功能以及pH值调节等.结果表明,PFOS导致的出生早期死亡与神经系统发育有关,PFOS可能通过改变脑组织血氧平衡,影响正常的中枢神经系统功能和发育过程而使新生儿的存活率下降.     

上海市实施清洁空气行动计划的健康收益分析

为掌握上海市实施清洁空气行动计划(2013~2017年)的人群健康收益,综合采用空气质量数值模拟、健康风险评估、环境价值评估方法定量评价行动计划实施后居民大气PM_(2.5)暴露水平变化及健康和经济效益.结果表明,PM_(2.5)年均暴露浓度在35μg·m~(-3)及以下的人口比例由基准年的1.62%上升至控制年的34.06%,归因PM_(2.5)暴露死亡风险由基准年的15.2%下降至控制年的11.9%.实现的健康收益总和为118.41亿元(95%CI:50.24~178.19亿元),占2013年上海市国民生产总值0.55%(95%CI:0.23%~0.82%).行动计划的实施对保护人群健康具有积极作用,外环线以内人口密集且PM_(2.5)降幅较高的区域健康收益更加显著.     

Women and children last: An essay on sex discrimination in disasters

In general, little attention has been given to differential survival between the sexes in disasters. Consideration of physiological differences between males and females would suggest that, all things being equal, morbidity and mortality after disaster, particularly where food shortage is involved, should indicate an excess male mortality. Such statistics as exist in disasters, as in chronic underdevelopment, show that it is females and especially girl children who are at highest risk. The basis of this lies in sex discrimination which is implicit in most social systems.     

Mortality of pollen beetle (Meligethes spp.) larvae due to predators and parasitoids in rape fields and the effect of conservation strips

In 1996–1999, different mortality factors of pollen beetle larvae were investigated in twenty six rape fields in the northern part of Switzerland which had either a wild flower strip or an extensively managed meadow adjacent to the long side of the field. At 3 and 30 m into the crop from the conservation strip, total mortality, mortality from predators, parasitoids and unspecified factors were measured. Total pollen beetle larval mortality was 66–96%. Mortality caused by predators was 16–27% and there was no significant difference between mortality at 3 m and that 30 m from the extensively managed meadows. However, in fields with wild flower strips adjacent to them, the percentage mortality from predators was significantly greater at 30 m than at 3 m. The range of parasitism of pollen beetle larvae was 0–54% and was on average greater at 3 m than at 30 m. In fields with wild flower strips, the percentage parasitism with Tersilochus heterocerus was significantly higher than in fields with extensively managed meadows. However, mortality from all parasitoids was only 1–2% and there was no significant difference between 3 and 30 m. The effect of parasitoids on pollen beetle mortality was masked by the high unspecified mortality and the mortality from predators. The unspecified mortality was 46–72% and was significantly greater in 1998 and 1999 than in 1996 and 1997. These differences are probably because of meteorological factors (wet in 1999 and dry in 1998). The possible influences of the two types of conservation strips on pollen beetle larval density were investigated. The results show that in fields with adjacent wild flower strips, the pollen beetle larvae were more evenly distributed (but not significantly so) than in fields with extensively managed meadows where larval density decreases faster from the edge into the rape field.