对活性污泥中6种内分泌干扰物的定量测定

针对活性污泥中6种内分泌干扰物（Endocrine Disrupting Compounds,EDCs）：双酚A（BPA）,雌酮（E1）,17β-雌二醇（E2）,雌三醇（E3）,17α-乙炔雌二醇（EE2）和己烯雌酚（DES）,建立了快速溶剂萃取（Accelerated Solvent Extractor,ASE）,固相萃取（SPE）净化,GC-MS检测的测试方法.对比分析了不同衍生化试剂、衍生化条件对分析结果的影响,同时优化了净化步骤.通过所建立的方法对6种EDCs在污泥中的浓度进行分析,检测回收率为77.2%—118.3%,相对标准偏差小于9%.应用该方法测定了重庆某2个污水处理厂剩余污泥中的EDCs浓度.     

PRA在焦化厂污染土壤修复目标值制定中的应用

以某焦化污染场地为例,采用PRA(概率风险评价)方法研究了17个人体暴露参数和5个土壤理化性质参数的不确定性对土壤中8种污染物修复目标值的影响.结果表明:PRA与DRA修复目标值的比值仅深层Nap为0.9,其余为1.11~2.49,因此,采用传统的DRA(确定性风险评价)方法制定的修复目标值容易偏保守;将土壤中污染物含量降低到PRA修复目标值所产生的暴露风险均在可接受的范围内,但表层土壤Ben对人体健康产生危害的可能性最大;参数敏感性分析的结果表明成人暴露周期(EDa,贡献率为35%~59.8%)和儿童暴露周期(EDc,6.2%~20.2%)对各污染物修复目标值不确定性的影响均较大,此外,土壤理化性质参数,如土壤有机碳含量(foc)、土壤孔隙中空气体积比(θair,vad)和土壤孔隙中水体积比(θwater,vad)对易挥发的Ben和Nap影响较大,儿童每日土壤摄入量(IRs-c)对不易挥发的BaA~DBA影响较大.     

Choice set formation for outdoor destinations: The role of motivations and preference discrimination in site selection for the management of public expenditures on protected areas

Effective public expenditure currently dominates the management focus of many protected areas. This calls for explicit modeling of constraints and motivations that, respectively, obstruct and stimulate visits to selected outdoor destinations. Choice set formation is the result of screening and/or inclusion of specific sites (alternatives) to form the set of sites considered in real choices. Evidence shows that the omission of a structural representation of choice set formation is harmful to econometric inference. Yet, the literature has largely ignored the underlying behavioral phenomenon. We show, using a discrete choice experiment involving selection among seven recreational sites in an Italian national park, that choice set formation is behaviorally relevant, even after controlling for preference discrimination. Motivations (why visit?) are important determinants of preliminary site screening for choice set inclusion, as well as site selection, justifying the additional value of such modeling extension.     

Ecotoxicological effects of waterborne PFOS exposure on swimming performance and energy expenditure in juvenile goldfish (Carassius auratus)

The potential risks of perfluorooctane sulfonate (PFOS) are of increasing ecological concern. Swimming performance is linked to the fitness and health of fish. However, the impacts of PFOS on swimming performance remain largely unknown. We investigated the ecotoxicological effects of acute exposure to PFOS on the swimming performance and energy expenditure of juvenile goldfish (Carassius auratus). The fish were exposed to a range of PFOS concentrations (0, 0.5, 2, 8 and 32 mg/L) for 48 hr. The spontaneous swimming activity, fast-start swimming performance, critical swimming speed (Ucrit) and active metabolic rate (AMR) of the goldfish were examined after exposure to PFOS. PFOS exposure resulted in remarkable effects on spontaneous activity. Motion distance was reduced, and the proportion of motionless time increased with increasing concentrations of PFOS. However, no significant alterations in the fast-start performance-related kinematic parameters, such as latency time, maximum linear velocity, maximum linear acceleration or escape distance during the first 120 msec after stimulus, were observed after PFOS exposure. Unexpectedly, although PFOS exposure had marked influences on the swimming oxygen consumption rates and AMR of goldfish, the U crit of the goldfish was not significantly affected by PFOS. This may result in a noteworthy increase in the energetic cost of transport. The overall results indicate that, in contrast to spontaneous activity, underlying swimming capabilities are maintained in goldfish after short-term exposure to PFOS, but energy expenditure during the process of swimming is dramatically aggravated.     

2012—2016年中央财政生态环境保护支出分析

本文基于财政"节能环保"支出科目,整合散落在其他科目里的生态环境保护支出,分析中央财政（含本级投入与专项转移支付）近五年（2012—2016年）的生态环境保护支出现状,发现：中央用于生态建设和保护方面的支出最多,五年支出均值为933.1亿元;其次是环境污染治理支出,五年支出平均值为773.4亿元。同时,基于现状分析及工作实践发现中央财政生态环境保护支出存在规模偏小、比重偏低、增长的稳定性不足等问题,中央财政需进一步优化支出方向和结构,加强绩效评价和结果应用。     

Influence of Body Weight and Size on the Mode of Wintering in Hibernators of the Family Sciuridae in Northeastern Russia

Energy expenditures in the Siberian chipmunk (Tamias sibiricus jacutensis Ognev, 1935) and long-tailed ground squirrel Citellus undulates jacutensis Brandt, 1843 during hibernation were compared. Energy expenditures were assessed by analyzing changes in body weight and gas exchange rate. The animals were weighed either monthly throughout the winter (26 ground squirrels and 9 chipmunks) or continuously (four to six times a day) in five ground squirrels (395 h) and three chipmunks (696 h). At a constant ambient temperature, the body weight of animals in both species decreased almost linearly during the day. The decrease in the body weight of hibernating grounds squirrels and chipmunks over a single short hibernation cycle was also approximated by a linear function, irrespective of species, age, and sex.     

Age-related foetal sex ratio bias in Iberian red deer (<Emphasis Type="Italic">Cervus elaphus hispanicus</Emphasis>): are male calves too expensive for growing mothers?

Several theories predict offspring biases towards males or females with increasing reproductive resources of the mother to maximize reproductive returns by offspring, or as a result of prohibitive cost of the most expensive sex for young mothers or those in poor condition. This study examines foetus sex of 221 harvested hinds in a food-supplemented game estate for 10 years, according to hind age class (yearlings, subadults or adults), precise age, body mass and condition, and jaw length. A logistic model showed that hinds had a greater probability of bearing a male foetus with increasing age class, but not with any other variable. The greatest bias was found in yearling hinds. After controlling for age class and mass, jaw length was smaller in pregnant compared to non-pregnant yearlings and subadults, which suggests a trade-off between reproduction and growth. The bias towards females in yearlings increased as gestation proceeded, which suggests that the bias might be a result of selective abortion of male foetuses. Although results do not exclude an investment in males to increase number of grand-offspring, they suggest that young hinds may produce daughters as a trade-off between low energetic-cost offspring and their need to grow.Communicated by S. Krackow     

Zebra finches,<Emphasis Type="Italic"> Taeniopygia guttata</Emphasis>, with elongated tails delay taking flight during group take-offs

Zebra finches with tail-elongations left perches during induced take-offs consistently later than unmanipulated controls. Latency in take-off was the same for both a short pintail-elongation (27% of finch long-axis) and an extreme pintail-elongation (49% of finch long-axis). There was no evidence for artificial pintails increasing energy expenditure, as predicted by flight aerodynamics models. Neither flight metabolic rate determined using the doubly labelled water technique, nor resting metabolic rate or food intake rates were affected. Hence, the energetic costs of elaborate pintails seem likely to be small and perhaps biologically trivial. In contrast, pintails appear to confer a manoeuvrability cost, as found in previous studies of long tails. Latency in take-off may be induced by an increased risk of collision with conspecifics during group take-offs and landings. Alternatively, latency may represent a change of predator-avoidance strategy, because taking off within the group does not minimise predation risk when handicapped by tail-elongation. The effects of tail-elongation are likely to be context-dependent and may differ between solitary species and more gregarious species that fly or forage in flocks.Communicated by W. Wiltschko     

Mechanisms enabling sperm economy in blenniid fishes

Sperm competition, cost of spermatogenesis and spawning frequency are known to influence ejaculate expenditure. Accordingly, males, particularly those with high reproductive costs, are expected to have evolved mechanisms enabling them to prudently allocate sperm, such as the fractioning of ejaculate expenditure or the semi-cystic type of spermatogenesis, hypothesised to favour the production of small ejaculates. In this study, we investigate sperm competition risk, ejaculate size and mode of ejaculate release in seven polygynous blenniid fish where males provide sole paternal care of eggs. In addition, we estimated the relative size of the two parts composing the male gonad, the strictly testicular (testicular lobules or testis) and the glandular (testicular gland), as the development of the latter is indicative of the level of semi-cystic spermatogenesis. In all the examined species, eggs were laid one by one, and the sperm expenditure at mating, evaluated as the total number of sperm released per mating, was parcelled out in several successive ejaculations, allowing males to adjust the release of sperm to the duration of egg deposition. In accordance with sperm competition theory, species experiencing higher sperm competition risk allocated more in sperm, both considering ejaculate size and ejaculate expenditure per mating. An increase in sperm expenditure was paralleled by the development of the testis at the expense of the testicular gland. Smaller species, whose males do not face sperm competition risk and fecundity is low, produced smaller ejaculates and exhibited a more developed testicular gland, supporting the hypothesis that a semi-cystic type of spermatogenesis is a mechanism allowing sperm economy.     

The real effect of legal institutions: Environmental courts and firm environmental protection expenditure

This paper evaluates the real effects of environmental justice reform on environmental governance at the firm level. Using the establishment of environmental courts in China as a quasi-natural experiment, our difference-in-differences estimation shows that: (1) environmental courts significantly enhance environmental investment by firms, and this relationship is robust to different specifications and alternative measures; (2) three possible channels are the improved levels of justice and enforcement of environmental protection, and the mitigation of local government intervention; (3) our findings are particularly pronounced in subsamples with severe local protectionism, state-owned enterprises (SOEs), and non-SOEs with political connections; (4) at the city-level, environmental courts significantly increase air quality and promote cities to cross the inflection point of the environmental Kuznets curve earlier. Overall, this paper reveals the micro-mechanisms behind the real effects of environmental justice on firm environmental investment, thus providing timely implications for regulators concerned with environmental protection.