新浪博客

科技日报--世界上最大的植物（下）

2022-06-30 10:58阅读：

http://blog.sina.cn/dpool/blog/u/5119766161

科技日报--世界上最大的植物（下） The shallow, salty waters of Shark Bay. Credit: Angela Rossen
鲨鱼湾的浅咸水。图片来源：安吉拉•罗森
It is challenging to determine the exact age of a seagrass meadow, but we estimate the Shark Bay plant is around 4,500 years old, based on its size and growth rate.
确定海草草地的确切年龄是一项挑战，但根据其大小和生长速度，我们估计鲨鱼湾的海草大约有 4,500 岁了。 
Other huge plants have been reported in both marine and land systems, such as a 6,000-tonne quaking aspen in Utah, but this seagrass appears to be the largest to date.
据报道，在海洋和陆地系统中都有其他巨大的植物，例如犹他州的 6,000 吨颤杨，但这种海
草似乎是迄今为止最大的。
Other huge seagrass plants have also been found, including a closely related Mediterranean seagrass called POSIDONIA OCEANICA, which covers more than 15 km (9 miles) and may be around 100,000 years old.
还发现了其他巨大的海草植物，包括一种与地中海海草密切相关的，称为 POSIDONIA OCEANICA，它的覆盖超过 15 公里（9 英里），可能约 有10 万岁了。
为什么这很重要？
2010-11 年夏季，一场严重的热浪袭击了西澳大利亚海岸线的陆地和海洋生态系统。
鲨鱼湾的海草草地在热浪中遭受了广泛的破坏。然而，带状海草草地却已经开始恢复。
This is somewhat surprising, as this seagrass does not appear to reproduce sexually – which would normally be the best way to adapt to changing conditions.
这有点令人惊讶，因为这种海草似乎不会有性繁殖，这通常是适应不断变化的环境的最佳方式。
We have observed seagrass flowers in the Shark Bay meadows, which indicates the seagrass are sexually active, but their fruits (the outcome of successful seagrass sex) are rarely seen.
我们在鲨鱼湾的草地观察到海草花，这表明海草性活跃，但它们的果实（海草性成功的结果）却很少见。
科技日报--世界上最大的植物（下）
Flowers emerging from Posidonia australis seagrass. Credit: Angela Rossen
从 Posidonia australis 海草中出现的花朵。图片来源：安吉拉•罗森
Our single plant may in fact be sterile. This makes its success in the variable waters of Shark Bay quite a conundrum: plants that don’t have sex tend to also have low levels of genetic diversity, which should reduce their ability to deal with changing environments.
我们的单一植物实际上可能是不育的。这使得它在鲨鱼湾多变水域的成功成为一个难题：没有性行为的植物往往也具有低水平的遗传多样性，这应该会降低它们应对不断变化的环境的能力。
However, we suspect that our seagrass in Shark Bay has genes that are extremely well-suited to its local, but variable environment, and perhaps that is why it does not need to have sex to be successful.
然而，我们怀疑我们在鲨鱼湾的海草具有非常适合其当地但多变的环境的基因，也许这就是为什么它不需要发生性行为就可以成功的原因。
Even without successful flowering and seed production, the giant plant appears to be very resilient. It experiences a wide range of water temperatures (from 17ºC/63ºF to 30ºC/86ºF in some years) and salt levels.
Despite these variable conditions and the high light levels (which are typically stressful for seagrass), the plant can maintain its physiological processes and thrive. So how does it cope?
即使没有成功的开花和种子生产，这种巨型植物似乎也很有弹性。它的水温（在某些年份从 17ºC/63ºF 到 30ºC/86ºF）和盐分水平范围都很广。
尽管有这些多变的条件和高光照水平（这通常对海草造成压力），但海草可以维持其生理过程并茁壮成长。 那么它是如何应对的呢？
We hypothesize that this plant has a small number of somatic mutations (minor genetic changes that are not passed on to offspring) across its 180 km (112 mile) range that help it persist under local conditions.
我们假设这种植物在其 180 公里（112 英里）的范围内有少量体细胞突变（不会传递给后代的微小遗传变化），这有助于它在当地条件下持续存在。
However, this is just a hunch and we are tackling this hypothesis experimentally. We have set up a series of experiments in Shark Bay to really understand how the plant survives and thrives under such variable conditions.
然而，这只是一种直觉，我们正在通过实验解决这个假设。我们在鲨鱼湾进行了一系列实验，以真正了解植物如何在如此多变的条件下生存和繁衍。
科技日报--世界上最大的植物（下）
Transplant experiments. Credit: Martin Breed
移植实验 图片来源：Martin Breed
THE FUTURE OF SEAGRASS
Seagrasses protect our coasts from storm damage, store large amounts of carbon, and provide a habitat for a great diversity of wildlife. Conserving and also restoring seagrass meadows has a vital role in climate change mitigation and adaptation.
海草的未来
海草保护我们的海岸免受风暴破坏，储存大量碳，并为多种野生动物提供栖息地。保护和恢复海草草地在减缓和适应气候变化方面发挥着至关重要的作用。
Seagrasses are not immune from climate change impacts: warming temperatures, ocean acidification, and extreme weather events are significant challenges for them.
海草不能免受气候变化的影响：气温升高、海洋酸化和极端天气事件对它们来说是重大挑战。
However, the detailed picture we now have of the great resilience of the giant seagrass of Shark Bay provides us with the hope they will be around for many years to come, especially if serious action is taken on climate change.
然而，我们现在对鲨鱼湾巨型海草的巨大复原力的详细了解为我们提供了希望，它们将在未来很多年存在，特别是如果对气候变化采取认真行动的话。

我的更多文章

下载客户端阅读体验更佳

APP专享