更多的植物会灭绝，而不是以前的想法

新的研究发现，自欧洲定居以来，美国大陆和加拿大灭绝了65种植物物种。这几乎是研究人员之前估计或任何研究过的物种的两倍。

该研究发表在杂志保护生物学由来自美国的16个保护和生物学研究人员团队。

虽然最近的研究表明，近600家工厂在全球灭绝，包括16个美国的38种植物种类，而是研究人员发现他们描述为“更可怕的情况”。他们的成绩于31个州，哥伦比亚地区和加拿大安大略省的灭绝物种文件介绍了比以前估计更大的面积更多的灭绝。

他们说，它可能是，所记录的灭绝高度低估了丢失的植物种类的实际数量。

灭绝最具灭绝的国家是加州（19），德克萨斯州（九），然后是佛罗里达州和新墨西哥州，每个都有四个。加拿大只有一个植物灭绝。

"There were a number of interesting discoveries. I was surprised at the geographic distribution of extinction events being southwestern. We were very surprised at the number of plants that were apparently known from a single site (i.e. extremely narrow geographic distribution)," lead author, ecologist and botanist Wesley Knapp of the North Carolina Natural Heritage Program of the North Carolina Department of Natural and Cultural Resources, told Treehugger.

"I think the largest surprise is the fact that up to seven plants are extinct in the wild (i.e. only known from botanical gardens), and some of these species weren’t known to be extinct in the wild before this study. Frankly, this is shocking."

Knapp说，现在只在野外灭绝的物种现在只存在于植物园和他们没有意识到他们在世界上有最后活植物的设施。

有趣的地理问题

Knapp说，一些用于灭绝的地理位置也是令人惊讶的。

“新英格兰比佛罗里达州更灭绝的事实是违反直觉的，突出了这种事实，即在被发现之前的物种可能灭绝的原因。新英格兰是一个特殊的领域，但植物学不是佛罗里达州的多样化，这位于全球生物多样性热点，含有数百种食植物种类。“

研究人员写道，灭绝的原因难以确定。Knapp表示，结果是重要的，希望研究人员可以从中学习。

“有一点，我希望人们从事工作是科学界需要更加合作地工作。知道找到稀有植物的群体，如北卡罗来纳自然遗产计划，需要与种子银行和保护花园密切合作help conserve genetic material (i.e. ex situ保守），“Knapp说。

"We should start by focusing on global single site endemics. We also need to closely look at our ‘protected lands’ to make sure we’re capturing the full array of biodiversity. Lastly, many conservation groups work on larger landscape level initiatives or focal areas. This is wonderful for ecosystem function, however the importance of small site protection for biodiversity conservation is imperative to protect extinction."

当Knapp是一名本科学生时，他被任务调查了马里兰州的两个县，寻找稀有植物物种。他说，植物谷物的Micranthemum（micranthemum micranthemoides）捕获了他的想象力，因为这是唯一一个被认为在马里兰州灭绝的植物。

"I did not realize extinct plants were found in places like Maryland, assuming they were only in far off species places like the Amazon. Over the years I’d talk to other botanists about what plants were extinct in their states. I found that most people didn’t know much about the plants that were presumed extinct where they were working, so I started maintaining a list of the extinct species," he said. "To my surprise, the work had not been done and everyone was on board that it was an important topic to investigate."