DNA泄密:古北美野牛兴衰有新解

美洲野牛急速穿越平原的蹄印是美国西部持久不变的象征。西部牛仔一直是美国西部的代言人。无论在遥远的古代，还是逝去的近代，野牛曾经是美国西部的一大宏伟壮观的景象。黄沙漫漫，远处传来轰隆的响声，也许就是一群野牛飞奔过来了。     

世界九大航天发射场

肯尼迪航天中心位于美国东部佛罗里达州东海岸的梅里特岛,成立于1962年7月,是美国宇航局进行载人与不载人航天器测试、准备和实施发射的最重要场所。     

治污高手Halomonas campisalis

美国蒙大拿州立大学化工教授Brent Peytonjiqi及其同事描述了以前未曾被发现过的Halomonas campisalis细菌。     

Sedimentary record of polycyclic aromatic hydrocarbons in Lake Erhai, Southwest China

The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhal in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method.The total organic carbon (TOC) normalized total PAHs concentrations (sum of US Environmental Protection Agency proposed 16 priority PAHs) ranged from 31.9 to 269 μg/g dry weight (dw),and were characterized by a slowly increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments.The PAHs in the sediments were dominated by low molecular weight (LMW) PAHs,suggesting that the primary source of PAHs was low- and moderate temperature combustion processes.However,both the significant increase in high molecular weight (HMW) PAHs in the upper sediments and the vertical profile of diagnostic ratios pointed out a change in the sources of PAHs from low-temperature combustion to high-temperature combustion.The ecotoxicological assessment based on consensus-based sediment quality guidelines implied that potential adverse biological impacts were possible for benzo(ghi)perylenelene and most LMW PAHs.In addition,the total BaP equivalent quotient of seven carcinogenic polycyclic aromatic hydrocarbons (BaA,CHr,BbF,BkF,BaP,DBA and INP) was 106.1 ng/g,according to the toxic equivalency factors.Although there was no great biological impact associated with the HMW PAlls,great attention should be paid to these PAH components based on their rapid increase in the upper sediments.     

中美污染物排放标准比较研究（上）

本文在系统分析美国大气与水污染物排放标准体系的基础上，我国排放标准从制定到实施中存在的不足，提出了改进我国排放标准工作的建议。     

美国水质保护及其对亚洲国家的启示

美国是世界上最早开展水质保护立法的管理的国家，公众参与水资源管理的历史最长，其经验对工业化和城市化发展的亚洲国家有借鉴与指导意义。     

美国《1990年油污水》及船舶油污损害赔偿机制概述

美国没有加入《１９６９年责任公约》和《１９７１年基金公约》，而是通过制定《１９９０年油污法》而建立了国内船舶油污损害赔偿机制。笔者曾于１９９３年前往美国就此问题专门进行了考察。在中国正在研究建立国内船舶油污损害赔偿机制之际，将的经验作一总结，希望能有所裨益。     

美国人口突破3亿向4亿迈进不值得庆贺

人口增长是不断扩大的分母,它会使每个人分到的资源份额缩小。影响到水的短缺、粮田转向非农使用、交通拥挤、垃圾围城、过度捕捞、国家公园摩肩接踵、依赖进口石油及其它等,这些都会降低我们生活的质量。