Mating patterns in three <Emphasis Type="Italic">Bufo andrewsi</Emphasis> populations at different latitude

Body size-dependent mating pattern is thought to a consequence of the sexual selection on phenotypic characters. In the view, we investigated the mating patterns in Bufo andrewsi from three populations at different latitude in three Nature Reserves (i.e. Wanglang, Yele and Fengtongzhai) in China from early- March to late-May 2013 and 2014. The results showed that average body size did not differ significantly between amplectant and non-amplectant males within each population. We found a significantly positive relationship in body size between the amplectant males and amplectant females in Wanglang population, but not in Qiqiao and Yele populations. The strength of size-dependent mating was not correlated with the malebiased operational sex ratios (OSRs), suggesting that intensity of male-male competition at nights do not result in variation in size-dependent mating patterns in B. andrewsi among populations.     

渗滤液氨氮在地下咸水环境中的迁移过程

海滨填埋场是沿海地区垃圾处理的一个重要选择,但其渗滤液泄漏引发的地下环境污染具有一定的独特性。以渗滤液中长时间保持高浓度的氨氮作为指标,通过构建砂箱实验,探讨咸水条件下氨氮在地下环境中的迁移转化过程。结果表明,在地下水环境中,渗滤液氨氮较易沿水流水平方向扩散,扩散速度随空间推移不断降低,从开始的4 cm/d降低到出水处的3.2 cm/d;其衰减率沿饱和区、过渡区、调整区依次增高;同时其衰减率随时间的增加不断降低,在实验的第15、25、35、45和55天,分别为100%、98.7%、95.6%、91.8%和83.5%。     

Revealing photon transmission in an ultraviolet reactor: Advanced approaches for measuring fluence rate distribution in water for model validation

Fluence rate (FR) distribution (optical field) is of great significance in the optimal design of ultraviolet (UV) reactors for disinfection or oxidation processes in water treatment. Since the 1970s, various simulation models have been developed, which can be combined with computational fluidic dynamic software to calculate the fluence delivered in a UV reactor. These models strive for experimental validation and further improvement, which is a major challenge for UV technology in water treatment. Herein, a review of the simulation models of the FR distribution in a UV reactor and the applications of the current main experimental measurement approaches including conventional flat-type UV detector, spherical actinometer, and micro-fluorescent silica detector (MFSD), is presented. Moreover, FR distributions in a UV reactor are compared between various simulation models and MFSD measurements. In addition, the main influential factors on the FR distribution, including inner-wall reflection, refraction and shadowing effects of adjacent lamps, and turbidity effect are discussed, which is helpful for improving the accuracy of the simulation models and avoiding dark regions in the reactor design. This paper provides an overview on the simulation models and measurement approaches for the FR distribution, which is helpful for the model selection in fluence calculations and gives high confidence on the optimal design of UV reactors in regard to present methods.     

加强环境监测的全过程质量管理

质量管理是环境监测赖以生存和发展的基础,目前,环境监测质管工作中“重结果、轻过程”的问题仍然普遍存在,加强全过程质量管理才能确保监测数据的准确性和可靠性,为实现环境资源的可持续利用提供强有力的技术支撑。文章叙述了环境监测质量管理的发展概况,引出全过程质量管理的概念,提出从提高全员质量意识、建立健全质量管理体系、实施全过程的质量保证、加大质控工作力度等几方面加强环境监测的全过程质量管理,从而提升环境监测机构整体质量管理水平。     

浅谈龙江县人为水土流失的防治对策

本文分析了龙江县水土流失的成因及危害,并提出了机关的防治对策,对今后的水土保养、合理开发有一定的借鉴作用.     

引水工程前后西湖流场的数值模拟研究

采用Delft 3D水动力学计算模型,对西湖西进工程前后的流场进行了模拟,计算结果与实测资料较为吻合,模型真实可靠.各种工况下的流场模拟结果表明在不考虑风场的情况下,各进出水口的流量和位置决定了西湖的流场结构,而流场结构决定了水体的推移扩散规律.总体上,南湖水体推移扩散效果最好,西里湖、外湖和岳湖次之,北里湖最差,基本不能被置换.西湖水体的置换效果主要取决于可被置换区域的面积和引水量,而可被置换区域大小主要取决于流场结构.因此,在引水量不变的前提下,优化西湖水体置换效果的根本途径就是调整进出水口位置和流量大小,以改变流场结构.     

风景区中影视拍摄的环境规制研究

影视剧组在风景区的拍摄活动,往往造成风景区的环境破坏。文章首先对风景区中影视拍摄所造成的破坏类型进行分析,然后从相关责任主体方面探讨造成该问题的原因,最后根据环境规制发展的趋势,提出风景区中影视拍摄的规制对策：政府部门的强制性规制和影视剧组的自愿性规制两者相结合。     

硝化抑制剂的加量对生化需氧量值影响的探讨

BOD作为衡量水体受有机污染程度的重要指标,其反映的可生化降解性是其他参数无法替代的。在5日生化培养时间内,硝化作用的耗氧量取决于是否存在足够数量的能进行此种氧化作用的微生物,许多二级生化处理的出水和受污染较久的水体中,往往含有大量硝化微生物,因此测定这种水样时应抑制其硝化反应。通过对特定水体硝化抑制剂添加与否及加量多少对BOD5测定结果的影响,分析并探讨抑制特定水体硝化过程的最佳条件。在严格质量控制的基础上,对特定行业和环境水体的实际样品进行硝化抑制剂添加与否和加量及时间培养曲线等对比实验,通过所得到的比对数据以化学需氧量值与BOD5之间关系为基准,对硝化抑制剂的加量进行了探究。     

Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin

Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between enantiomers.In this study,enantiomers of insecticide beta-cypermethrin (beta-CP) were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval assays.The enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism (CD) at 236 nm.Better separation could be achieved at lower temperature (e.g.,20°C) and with lower levels of polar modifiers.Pure enantiomers were obtained on Chiralcel OD.The CD spectra of enantiomers were recorded.By comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was determined.The individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked body.The 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration (e.g.,0.3 mg/L).The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.