4种实用配方饲料对锦鲤诱食活性和生长的影响

试验用鱼选择锦鲤.根据动物摄食行为学原理,采用迷宫法和摄食率法为试验方法,配制4种添加甘氨酸的实用饵料,研究其对锦鲤诱食活性和生长的影响,实验结果用Excel和SPSS17.0软件进行分析.结果表明,4种实用饵料都对锦鲤具有诱食反应.其中,火棘(35m甘氨酸)P=0.003＜ 0.05,浒苔(35mg甘氨酸)P=0.001＜0.05,诱食效果有极显著意义.与对照组相比,喂食实用饵料的锦鲤增重率都有所提高,其中浒苔+50mg甘氨酸最为明显,达到8.44％,饵料系数降低到4.123.     

Spatial pattern of impervious surfaces and their impacts on land surface temperature in Beijing, China

Land surface temperature （LST）, which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces （IS） spatial patterns have on LST in Beijing, China. A classification and regression tree model （CART） was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper （TM） image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy （correlation coefficient of 0.94 and the average error of 8.59%）. Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.     

环境激素污染研究

综述了国内外环境激素的研究进展,介绍了环境激素的概念、种类、作用机制及其危害,提出了环境激素污染的防治措施。     

Isolation and algae-lysing characteristics of the algicidal bacterium B5

Water blooms have become a worldwide environmental problem.Recently,algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms.In this study,one strain of algicidal bacterium B5 was isolated from activated sludge.On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence,it was identified as Bacillusfusiformis.Its algae- lysing characteristics on Microcystis aeruginosa,Chlorella and Scenedesmus were tested.The results showed that:(1)the algicidal bacterium B5 is a Gram-negative bacterium.The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B.fusiformis reached 99.86%,so B5 was identified as B.fusiformis;(2)the algal-lysing effects of the algicidal bacterium B5 on M.aeruginosa, Chlorella and Scenedesmus were pronounced.The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-α.The greater the initial bacterial cell density,the faster the degradation of chlorophyll-α.The greater the initial algal cell density,the slower the degradation of chlorophyll-α.When the bacterial cell density was 3.6 x l07 cells/ml,nearly 90% of chlorophyll-αwas removed.When the chlorophyll-αconcentration was less than 550μg/L,about 70% was removed;(3)the strain B5 lysed algae by secreting metabolites and these metabolites could bear heat treatment.     

系统电磁环境效应要求和试验评估研究

目的提高武器系统适应日益复杂的电磁环境,提升装备的作战效能,提出合理的系统电磁环境效应要求,并开展试验评估,以验证指标是否得到满足。方法采用基于使用需求和标准分析的方法,针对系统级电磁环境效应的复杂性和特殊性,通过对电磁环境效应要求和标准的分析,提出采用建模仿真,预测电磁环境,开展缩比模型、1︰1模型试验验证等方法确定电磁环境效应指标和要求。结果提出了系统内自兼容、系统间兼容性和系统与外部电磁环境3大类14小类的系统电磁环境效应要求,分析了每项电磁环境效应要求对四大类典型系统的适用性,提出了开展系统电磁环境效应试验的方法和流程,为开展装备系统级电磁环境效应工程研制、试验和评估提供了技术支撑。结论采用提出并确定系统电磁环境效应要求和试验评估方法,实施武器系统的电磁环境效应控制和评估,对装备使用性能的充分发挥具有十分重要的意义。     

纳米氧化物对藻类致毒性研究进展

纳米技术的迅猛发展及纳米氧化物在化学产品、电子工业、结构材料、农业及制药等领域大量生产和广泛应用,人们开始关注纳米氧化物进入环境带来的潜在风险。本文综述了纳米氧化物对藻类毒性试验所取得的研究成果(包括毒性效应、生理毒性、致毒机理等),以及纳米氧化物在水体中与其他物质发生复合后产生的联合毒性,展望了纳米氧化物毒性效应的研究方向。     

Single and joint effects of pesticides and mercury on soil urease

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13%-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.     

碳税的三重效应分析——碳税政策实施效应的比较

碳税是一种重要的环境经济手段,其设立初衷是将环境成本内部化,减少化石能源的消费和碳排放量。20世纪90年代以来,许多国家和地区探索实施了碳税。但作为一个干预经济运行的政策手段,碳税不仅会产生环境效应,还会产生经济效应和分配效应。这些效应互相影响,最终效果存在较大的不确定性:碳税的引入会在本国或本地区带来碳排放量的一定程度下降,但也可能引起"碳泄漏"。同时,由于碳税干扰了能源价格,可能加大能源成本,对工业生产竞争力,以及居民福利、就业等产生影响。既利用碳税实现碳减排,又要避免碳税对市场的扭曲,影响经济目标的实现,还要避免对贫困阶层的不利影响,同时达到这些目标实非易事,因此各国引入碳税前大多非常谨慎。特别是近几年,全球经济持续低迷,各国正设法推动制造业发展以提振经济走出疲软态势,对征收碳税的积极性有所下降。我国是一个发展中国家,正处于经济结构转型、多项重要改革同时推进的艰难转型期,在当前世界经济增长放缓的大背景下,保增长促就业的任务也很重,考虑到碳税三种效应的复杂性和不确定性,建议我国开征碳税应非常慎重。     

药物及个人护理品的污染现状、分析技术及生态毒性研究进展

随着医药及洗化行业的快速发展,PPCPs（pharmaceuticals and personal care products,药物及个人护理品）的生产和使用量增长迅速,已经成为自然环境中具有潜在生态风险的一类新型污染物.由于PPCPs在环境中浓度低、检测难度大、生态风险具有潜伏性,高灵敏度的定量检测方法已成为研究的热点.比较了文献中常用的不同预处理方法〔液液萃取（liquid liquid extraction,LLE）、固相萃取（solid phase extraction,SPE）、固相微萃取（solid phase micro extraction,SPME）、超声波溶剂萃取（ultrasonic solvent extraction,USE）、加压液相萃取（pressurized liquid extraction,PLE）、微波辅助溶剂萃取（microwave assisted solvent extraction,MASE）〕和检测方法〔GC/MS（气相色谱-质谱）、GC/MS/MS（气相色谱-双质谱）、HPLC/MS（高效液相色谱-质谱）、HPLC/MS/MS（高效液相色谱-双质谱）〕对地表水、沉积物、饮用水等不同介质中PPCPs检出限和检出浓度的异同,发现水样预处理常采用固相萃取法,其具有高回收和富集倍数、消耗有机溶剂少、省时等优点;固相样品预处理常采用超声溶剂萃取,其具有操作简单、适用性广等优点;HPLC/MS/MS检测方法具有广泛适用性,可检测大多数PPCPs,并且操作简单、灵敏度高.PPCPs会在水生生物体富集,并会表现出抑制酶活性、蛋白质及核酸合成、干扰藻类生长、影响动物活动等毒性效应.建议未来应加强环境中超低浓度PPCPs定量、定性分析技术的研发与应用,同时加强其环境风险研究,为揭示PPCPs的环境归趋行为提供技术支持.