环境科学交叉关系学科Chapter12,13重点句子及翻译.docVIP

第十二章 生物多样性问题 Biodiversity is a broad term used to describe the diversity of genes, species, and ecosystems in a region. Extinction is the death of a species, the elimination of all the individuals of a particular kind. Biodiversity is lost when all the individuals of a particular kind die off------- that is, when a species becomes extinct. Extinction is a natural and common event in the long history of biological evolution. However, as we will see later in this section, extinction ----- and the resulting loss of biodiversity----is also a major consequence of human domination of the Earth. 生物多样性是一个广泛的术语，被用于描述一个区域中基因、物种和生态系统的多样性。物种灭绝是指某一物种的死亡，特定物种的所有个体全部消失。当某一特定物种的所有个体全部死亡时，也就是说，当某一物种灭绝时，生物多样性就会丧失。在生物进化的历史长河中，物种灭绝是一件自然的、普遍存在的事情。然而，正如我们将在本节后面所要看到的那样，生物灭绝，以及由此导致的生物多样性丧失，是人类主宰地球的主要后果。 Studies of modern local extinctions suggest that certain kinds of species are more likely than others to become extinct. 现代的区域性物种灭绝研究表明，某些物种要比其他物种更容易灭绝。 As technology advanced, wood was harvested for fuel and building materials, land was cleared for farming, streams were dammed to provide water power, and various mineral resources were exploited to provide energy and build machines.These modifications allowed larger human populations to survive, but always at the expense of previously existing ecosystems. 随着技术的进步，需要木材用作燃料和建筑材料，土地被清理用于农业生产，河流被建坝以提供水能，各种矿物资源被开发用以提供能量和制造机器。这些改造活动，使得更多的人口可以生存。但是，这些总是以牺牲原来存在的生态系统作为代价。 Since our population is so large and because we have an advanced technology, catching or killing other animals for food is relatively easy. In some cases, this has led to extinctions. 因为人口数量如此之大，再加上人类掌握着先进的技术，捕获或宰杀其他动物显得比较容易。在某些情况下，这就造成了物种灭绝。 Today, with over 6 billion people on Earth, nearly all of the Earths surface has been affected in some way by human activity. One of the major impacts of human activity has been to reduce biodiversity. 目前，全球人口已超过60亿，几乎所有的地球表面，都以某种方式受到了人类活动的影响。人类活动的主要影响之一就是减少了生物多样性。 Genetic diversity is a term used to describe the number of differe