“培养瓶中的实验差不多只能做到这个程度，自然条件下共生的物种数量要大得多。”琼斯指出。
"You can only do so much in a flask, and the mix of species would be much greater in a natural environment, " Jones pointed out.
不同季节的保护鸟类物种数有差异。
通常人们把关注点放在物种数量或者丰富程度上。
因此，监测锹虫物种数量是一项法律要求。
As a result, there was a legal requirement to monitor the species' Numbers.
相比之下，新发现的物种数量持续急剧增长。
By contrast, the number of newly discovered species continues to rise sharply.
自1993年来，已知的哺乳动物物种数增加了10%。
Since 1993 the number of known mammal species has increased 10 percent.
设计一般说来，保护区越大，区内物种数就越多。
In general, the larger the reserve, the greater the number of species in it.
平均而言，44个禁捕区内的物种数增长了23%。
Onaverage, the number of species in the 44 sites increased by 23%.
迄今为止，人类所发现的物种数量约为190万种1。
The number of living species thus far discovered is approximately 1.9 million.1.
“物种数量显著增加改变了生态系统的功能”，Sax说。
"The dramatic increase in the number of species has changed how the system functions," Sax said.
当空间异质性较高时，面积对鸟类物种数的影响是明显的。
The effect of area on the Numbers of bird species is obvious if the spatial heterogeneity is diverse.
该研究团队用以计算地球物种数量的是一种叫线性回归的方法。
The study team used a method called linear regression to calculate the number of Earth's species.
冬季少数生物还在活动，月间的总物种数和总个体数有所波动。
The total species and individual number fluctuated a little during the two months because some organisms were acting.
这是一个高山湖泊和完整土地上的植物和动物物种数百人的王国。
It is an intact land of lakes and mountains where hundreds of plants and animal species have their kingdom.
在2000到2001年间，IUCN评估的物种数量增长超过60%。
Between 2000 and 2011 the number of species assessed by the IUCN grew by over 60%.
即使濒危物种数量恢复，降低或者去除CITES的保护措施也十分困难。
Even when endangered populations recover, it has proved difficult to reduce or remove CITES protection.
微生物数量的估计值只能大致接近事实，就像估计地球上物种数量一样。
Estimates of microbial biomass, like estimates of the number of species on the planet, are only loose approximations.
他发现有大约三分之一的树种其DNA的改变同衍生出的物种数呈现正相关性。
He found that in about a third of them, there was more change in the DNA in those trees where more species had been generated.
这一过程无疑也会导致其他物种数量的下降，就像发生在这种蜥蜴身上的一样。
This process will no doubt cause population declines in other species, just as it has in the salamander species.
这种努力的目的是在于不使目前的物种数量减少，也确保濒危品种得以生存下来。
Efforts are aimed at preventing the depletion of present populations and ensuring the continued existence of the habitats targeted species need to survive.
沃姆博士及其同事发现，海洋的物种数越多，对于人类过度捕捞活动的恢复能力就更强。
Dr Wormand his colleagues discovered that the more species an ocean regionhas, the more robustly it seems to cope with overexploitation.
图表显示，我们能够看到动物物种数量下降的速度越来越快，而且这种趋势将会持续下去。
As is shown in the chart, we can see the number of animal species decreases faster and faster and this trend will continue.
我们目前已经描述过的物种数量为120万种，其中大多数为陆生生物，总数多于海洋生物。
About 1.2 million species have been formally described, the vast majority from the land rather than the oceans.
尽管生存在地球上的物种数量，我们可以估计个大概，但是我们一直找不到可信的方法来计算。
Although the number of species on the planet might seem an obvious figure to know, a way to calculate it with confidence has been elusive.
研究人员记录了会导致灭绝风险的物种数量变化事件，在这些事件中，物种的数量快速降到零。
The researchers documented changes to extinction risk, where species are moving most rapidly toward zero population.
研究人员记录了会导致灭绝风险的物种数量变化事件，在这些事件中，物种的数量快速降到零。
The researchers documented changes to extinction risk, where species are moving most rapidly toward zero population.
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