Distinctions between exotic and native species are artificial.
外来物种和本地物种的区分是人为的。
They prevent fish migrations and change aquatic habitats essential for native species.
它们阻止了鱼类迁徙，并改变了对本地物种至关重要的水生栖息地。
The other thing we're doing is getting rid of some of the foreign species that are growing in the gardens and putting back some native plants and trees.
我们正在做的另一件事是除掉生长在花园里的一些外来物种，并种回一些本地植物和树木。
In the years since the Pleistocene epoch, native species have adapted to the changing environmental there, plants, smaller animals, they have been evolving without megafauna for millennia.
在更新世以来的这些年里，当地的物种已经适应了那里不断变化的环境，植物，小动物，它们已经在没有巨型动物的情况下进化了几千年。
Many of the species native to California, such as the prickly chaparral, rely on fires to propagate.
加利福尼亚有许多土生土长的物种，比如多刺的灌木荆棘丛，依靠火来繁殖。
Both native and exotic species can become invasive, and so they all have to be monitored and controlled when they begin to get out of hand.
本土物种和外来物种都有可能成为入侵物种，因此当它们开始失控时，我们必须对它们进行监视和控制。
If a nonnative plant species invades an above-ground community of flora and fauna, it can alter links between the native above-ground community and the below-ground soil community.
如果一种外来植物入侵了地上的动植物群落，就会改变地上群落和地下土壤群落之间的联系。
The ecosystem down there can't handle this non-native species. It's destroying the environment.
当地的生态系统并不能应付这个外来物种。它正在摧毁我们的环境。
Rugosa rose is a species of rose native to eastern Asia.
蔷薇属玫瑰是原产于东亚的玫瑰品种。
A species of alumroot (Heuchera sanguinea) was native to the southwest United States and Mexico.
一种矾根属植物（珊瑚钟矾根属）原产于美国西南部及墨西哥。
Some of the lowest islands could be allowed to flood, providing habitat and food for smelt, salmon, and other native species.
海拔最低的一些岛屿如果适当泛滥的话，还可以为胡瓜鱼、鲑鱼和其他本地物种提供栖息地和食物。
But native species disappeared at a rate of roughly two per year, while more than one newcomer arrived.
但是本地土著物种在以大约每年两个的速度消失，而新的外来物种每年却不止一个。
Invasive animals and plants have devastated native species on many Pacific islands.
在许多太平洋岛屿上，外来动植物已经毁灭了本地物种。
At the Botanical garden on a hill above St John's, two areas showcase native species: the rock garden and the peat garden.
在圣约翰的一座小山上有一个植物园，里边有两个地方展示了本地物种：石园和泥炭园。
The more benign aliens, by contrast, were predicted to have arsenals also found in at least some native species.
相比之下，入侵性较弱的外来物种所具有的“武器库”可能至少同样存在于某些土产物种。
Indeed many places, such as large parts of Western Europe, sub-Saharan Africa and Australia, had no domesticable native species at all.
许多地方，如西欧大部，下撒哈拉非洲和澳大利亚，则完全没有可驯化的本地物种。
Some of the beasts that have been introduced, such as foxes, eat the native species, or their food, and many imported plants prove invasive and overwhelm the locals.
还有一些引进的动物，如狐狸，它们会吃本土的物种或抢它们的食物，并且许多引进的植物也带有侵略性，他们会破坏本地物种。
And because native species haven't had time to adapt to these new arrivals, many stand defenseless against the invaders.
而本地物种因为没有充分的时间适应入侵者，对它们的“攻城掠地”表现得毫无抵抗之力。
The spread of scale insects would have delighted one of the region's native species: the tropical fire ant, which is fond of dining on the sugary excrement of scale insects.
介壳虫的蔓延会让一种该地区的本土物种感到高兴：热带火蚂蚁。这种蚂蚁喜食介壳虫含糖的排泄物。
Scientists discovered the snails a year and a half later, after they had already pushed some native species close to extinction.
一年半之后，科学家发现了这种蜗牛，但那时它们已经快把当地一些物种推向灭绝的边缘。
Monk parakeets, which have established colonies in the home counties, are to be culled because they are alleged to pose a danger to crops, the electricity grid and native species.
已经在伦敦各郡建立群居点的和尚鹦鹉因为被认为威胁作物、电网及本土物种将受到清除。
Their population, now in the millions, threatens many native species across Australia.
它们的数量，现在已经上百万，对整个澳大利亚的很多本土生物种群造成了威胁。
In New Zealand, for example, there were about 2, 000 native species of plants.
例如在新西兰曾经有2000种本地植物。
In some case, non-native species of oysters are introduced after a population decline, and they bring with them diseases that further kill off the native oysters.
在一些例子中，非本土种类的牡蛎会在本土数量下降后引入，它们随身带来的疾病会进一步杀死光本土牡蛎。
Non-native plants sometimes threaten native species by using up nutrient resources.
有时，非本地植物通过耗尽营养资源而威胁本地物种。
Non-native plants sometimes threaten native species by using up nutrient resources.
有时，非本地植物通过耗尽营养资源而威胁本地物种。
应用推荐