TED 精彩演讲 |如何利用森林和真菌之间古老的伙伴关系

So we know forests play an essential role in regulating the Earth's climate. However, most of what we know about those forests is actually based on things we can measure aboveground. So historically, ecologists like myself would come to this place, and we’d count the number of tree stems we’d find. We’d identify which species they are, and today we’d probably remotely sense features of this forest canopy from space. And all of this absolutely makes sense. Aboveground is where photosynthesis happens. Photosynthesis is how carbon and energy enter forests. Photosynthesis is how trees can remove carbon dioxide from the atmosphere.

所以我们知道森林在调节地球气候方面发挥着重要作用。 然而，我们对这些森林的大部分了解 实际上是基于我们可以在地面上测量的东西。 所以从历史上看，像我这样的生态学家会来这个地方， 我们会数一数我们找到的树干的数量。 我们会确定它们是哪个物种， 今天我们可能会从太空遥感这片森林树冠的特征。 而这一切绝对是有道理的。 地上是光合作用发生的地方。 光合作用是碳和能量进入森林的方式。 光合作用是树木从大气中去除二氧化碳的方式。

However, we also know most trees are limited in some way, by soil resources like water or nutrients. And to access those resources, trees have to build roots. And trees build an incredible amount of roots. So in some forests, there can be as much or more biomass belowground, in root structures, as aboveground, in stems and leaves. Decades of research have now made very clear that belowground ecology -- so what’s going on in the soil -- is really essential to understanding how these forest systems work.

然而，我们也知道大多数树木在某种程度上 受到水或养分等土壤资源的限制。 为了获取这些资源，树木必须生根。 树木会长出数量惊人的根。 因此，在某些森林中，地下 的根结构中的生物量可能 与地上的茎和叶中的生物量一样多或更多。 数十年的研究现在已经非常清楚地表明 ，地下生态学—— 也就是土壤中发生的事情——对于理解 这些森林系统的运作方式确实至关重要。

However, if you follow these root systems all the way out to their terminal ends, the finest tips in the root system, and you look closely -- I mean super closely, like, you’re going to need a microscope closely -- you discover a place where the tree stops being a plant, and starts becoming a fungus. So most trees on Earth form a partnership, or what scientists call symbiosis, with mycorrhizal fungi.

然而，如果你一直追踪这些根系直到它们的末端， 根系中最好的尖端， 然后你仔细观察——我的意思是非常仔细， 就像，你需要一个显微镜来仔细观察—— 你找到一个地方，那里的树不再是植物，而是 开始变成真菌。 因此，地球上的大多数树木都与菌根真菌结成伙伴关系， 或者科学家称之为共生关系。

So this, in my opinion, is one of the most remarkable images ever captured of these organisms. So in the background, at the top, you can see this dense network of fungal hyphae. These are essentially like roots, but for fungi, instead of plants. And in the foreground, you can see these incredible, multinucleated fungal spores, which look totally unreal, but absolutely are. These are the reproductive structures of the fungus. These have the potential to become entirely new fungal networks.

因此，在我看来，这 是有史以来拍摄到的这些生物最引人注目的图像之一。 所以在背景的顶部， 你可以看到这个密集的真菌菌丝网络。 这些基本上像根，但对于真菌，而不是植物。 在前景中， 您可以看到这些令人难以置信的多核真菌孢子， 它们看起来完全不真实，但绝对是真实的。 这些是真菌的繁殖结构。 这些有可能成为全新的真菌网络。

Mycorrhizal fungi are essential to how basically all plants access limiting soil resources. There's actually evidence that when plants first made the evolutionary transition from living in water to living on land, they evolved this symbiosis before they even evolved roots. And so this partnership between forests and their fungi is ancient, and it stretches back hundreds of millions of years.

菌根真菌对于 基本上所有植物如何获取有限的土壤资源至关重要。 实际上有证据表明 ，当植物首次 从水中生活到陆地上的进化过渡时， 它们甚至在进化出根之前就已经形成了这种共生关系。 因此，森林与其真菌之间的这种伙伴关系由来已久， 可以追溯到数亿年前。

However, these roots don't have to be just fungi. They can also be, for instance, bacteria. So these circular structures in this root network are called root nodules. They house symbiotic, nitrogen-fixing bacteria. And what these bacteria do is actually convert nitrogen gas in the atmosphere into plant-usable forms, and in turn, they nurture plant growth.

然而，这些根不一定只是真菌。 例如，它们也可以是细菌。 所以这个根网络中的这些圆形结构 被称为根结节。 它们容纳共生的固氮细菌。 这些细菌所做 的实际上是将大气中的氮气 转化为植物可用的形式， 进而培育植物生长。

And the complexity of soil biology just keeps going. So these root symbionts are embedded in an even more complex network of free-living bacterial and fungal decomposers, and archaea and protists, microscopic soil animals, viruses ... The biodiversity of soil communities is astonishing. We now know a handful of soil can easily contain over 1,000 coexisting microbial species.

土壤生物学的复杂性还在不断发展。 因此，这些根系共生体嵌入了一个更为复杂的网络中，该网络 由自由生活的细菌和真菌分解者、 古生菌和原生生物、 微观土壤动物、病毒组成…… 土壤群落的生物多样性令人震惊。 我们现在知道，一小撮土壤 很容易包含 1,000 多种共存微生物。

And so all of this, this is the soil microbiome. This is the forest microbiome, this is the ecosystem microbiome. So breakthroughs in DNA sequencing technology have finally turned the lights on belowground. DNA has allowed us to see these microbial communities in unprecedented detail, and, only recently, at unprecedented scales.

所有这一切，这就是土壤微生物组。 这是森林微生物组，这是生态系统微生物组。 因此，DNA 测序技术 的突破终于让地下的灯亮了起来。 DNA 使我们能够 前所未有地详细了解这些微生物群落， 而且直到最近，我们才以前所未有的规模了解这些微生物群落。

Yet despite these breakthroughs, I'd argue we still don't know the answers to seemingly simple questions, like this: "What does a healthy forest microbiome look like?" We're far closer to answering a question like this for people than we are for plants. The Human Microbiome Project has really led in this area. So the human body is a microbial ecosystem. Each of us houses an incredibly biodiverse community of bacteria in our gut, and that has a profound impact on our health. This was discovered by medical microbiologists using DNA sequencing to characterize which bacteria live in hundreds of people's bodies. And importantly, also noting health features of those same people. So, are they sick? And if so, with what? What's their blood pressure, their digestive health, their mental health? And by combining all of that information, those microbiologists could begin to identify combinations of bacteria linked to health and disease. And these analyses became a road map for the development of human microbiome transplant therapies, which is essentially ecosystem restoration, but for your gut microbiome. And these therapies are now on the road to market to treat some of these diseases today.

然而，尽管取得了这些突破， 我认为我们仍然不知道看似简单问题的答案，例如： “健康的森林微生物群是什么样的？” 与植物相比，我们更接近于为人类回答这样的问题。 人类微生物组计划在这一领域确实处于领先地位。所以人体是一个微生物生态系统。我们每个人的肠道内都有一个生物多样性极其丰富的细菌群落，这对我们的健康有着深远的影响。这是医学微生物学家发现的，他们使用 DNA 测序来表征数百人体内存在的细菌。重要的是，还要注意这些人的健康特征。 那么，他们生病了吗？如果是这样，用什么？ 他们的血压、消化系统健康状况、 心理健康状况如何？ 通过结合所有这些信息， 这些微生物学家可以开始识别 与健康和疾病相关的细菌组合。 这些分析成为 开发人类微生物组移植疗法的路线图， 这本质上是生态系统恢复， 但针对的是肠道微生物组。 这些疗法现在正在走向市场 ，以治疗当今的一些疾病。

And so drawing from this work, my team asked, "What would it look like to take the Human Microbiome Project approach, but apply it to the forest?” What could we discover about the forest carbon cycle? Could we identify places where we could actually do belowground microbial restoration, and, in the process, combat climate change?

因此，根据这项工作，我的团队问道： “如果 将人类微生物组计划的方法应用于森林，会是什么样子？” 关于森林碳循环，我们能发现什么？我们能否确定我们可以实际进行地下微生物恢复的地方，并在此过程中应对气候变化？

Over the past three years, we’ve been working with forest scientists across Europe to do exactly that. In each of these locations, scientists have been documenting forest health for decades. And so, we asked our forest research partners to go out to each of these forests and collect a small sample of soil, which they then shipped back to our lab in Zurich so we could extract and sequence DNA, which allowed us to understand which microorganisms, and particularly fungi, live in each of these forests. And then finally, we used statistics and machine learning to relate which microorganisms live in a forest to a really important forest health metric: tree growth rate and carbon-capture rate aboveground.

在过去的三年里， 我们一直在与欧洲各地的森林科学家合作 来做到这一点。 数十年来，科学家们一直在记录其中每个地点的森林健康状况。 因此，我们要求我们的森林研究合作伙伴前往这些森林中的每一个并收集一小部分土壤样本，然后他们将其运回我们在苏黎世的实验室，以便我们提取和测序 DNA，这使我们能够了解哪些微生物，尤其是真菌，生活在这些森林中。最后，我们使用统计数据和机器学习将森林中的哪些微生物与真正重要的森林健康指标联系起来： 地上树木生长率 和碳捕获率。

Now, once we controlled for the environmental drivers of tree growth -- so how warm and wet each of these places is, as well as other variables we know control background site fertility -- we discovered that particularly which fungi colonize the roots of these trees is linked to threefold variation in how fast these trees grow, how fast they remove carbon dioxide from the atmosphere. So put another way, these correlations imply that you could have two pine forests, sitting side by side, experiencing the same climate, growing in the same soils. But if one of them was colonized by the right community of fungi on its roots, it could be growing up to three times as fast as that adjacent forest. And furthermore, these patterns were not driven by the presence of particularly high-performing species or strains, but instead, they were driven by biodiverse and completely different communities of fungi.

现在，一旦我们控制了树木生长的环境驱动因素—— 每个地方的温暖和潮湿程度， 以及我们知道的其他控制背景场地肥力的变量—— 我们发现，特别是哪些真菌在 这些树的根部繁殖与这些树木生长 速度、它们从大气中清除二氧化碳的速度的三倍变化有关。 所以换句话说，这些相关性意味着你可以有两片松树林，并排坐着，经历相同的气候，生长在相同的土壤中。但如果其中一个被正确的真菌群落定殖在它的根部， 它的生长速度可能是邻近森林的三倍。 此外，这些模式并不是 由特别高性能的物种或菌株的存在驱动的， 而是由生物多样性和完全不同 的真菌群落驱动的。

And so these fungal signatures are super exciting to us because they imply an opportunity to manage, and in many cases, actually rewild the forest fungal microbiome.

因此，这些真菌特征对我们来说非常令人兴奋， 因为它们意味着管理的机会， 在许多情况下，实际上是重新野生森林真菌微生物组。

So, for example, can we reintroduce fungal biodiversity into a managed timber forestry landscape? And in the process, can we make those trees grow faster? Can we make them capture more carbon in their tree stems and in their soils? Can we rewild the soil and combat climate change? And these aren't just rhetorical questions -- we've actually started doing this.

那么，例如，我们能否将真菌生物多样性重新引入 受管理的用材林景观中？ 在这个过程中，我们能让那些树长得更快吗？ 我们能让它们在树干和土壤中捕获更多的碳吗？ 我们能否重建土壤并应对气候变化？ 这些不仅仅是修辞问题—— 我们实际上已经开始这样做了。

So this is one of our field trials in Wales, in the United Kingdom. It’s run in collaboration with the charity there called the Carbon Community. It’s 28 acres, or 11 hectares, and it's set up as a block-randomized controlled trial. This is analogous to how you would run a drug trial, but in this case, it's for trees instead of people. And here, we do a pretty straightforward experiment. We either plant trees, business as usual -- which is just direct planting of seedlings into the ground -- or we plant trees, and at the moment of planting, we add a small handful of soil. But it's not just any soil. It's soil sourced from a forest our analyses have identified as harboring potentially high-performing fungi. So since we reintroduced microbial biodiversity into some of these sites, we've observed that where we actually did that, we've been able to accelerate tree growth and carbon capture in tree stems by 30 to 70 percent, depending on the tree species. Or put another way -- where we manipulated and rewilded the invisible microbiology of this place, we’ve begun to change how that entire place works.

这是我们在英国威尔士进行的实地试验之一。 它与当地名为 Carbon Community的慈善机构合作运营。 它占地 28 英亩或 11 公顷，它被设置为一个块随机对照试验。这类似于你将如何进行药物试验，但在这种情况下，它是针对树木而不是人。在这里，我们做了一个非常简单的实验。我们要么像往常一样种树——这只是将幼苗直接种到地里——要么我们种树，在种植的时候，我们加了一小把土壤。但这不仅仅是任何土壤。这是来自森林的土壤 我们的分析已确定其中藏有潜在的高性能真菌。 因此，自从我们将微生物生物多样性重新引入 其中一些地点以来， 我们观察到，在我们实际这样做的地方， 我们已经能够将树木生长和树干中的碳捕获加速 30% 到 70%，具体取决于树种。 或者换句话说—— 我们操纵和重新野化了这个地方的无形微生物， 我们已经开始改变整个地方的运作方式。

Now it's important to emphasize that we're really excited about these findings, but we also understand they're still early. We want to see many more large-scale field trials and many more locations with many more years of data.

现在需要强调的 是，我们对这些发现感到非常兴奋， 但我们也知道它们还为时过早。 我们希望看到更多的大规模现场试验 和更多的地点以及更多年的数据。

However, beyond just these carbon and climate outcomes, I think the most exciting thing here is that we can actually do this with wild and native and biodiverse combinations of microorganisms. And while we pointed this approach at forestry, in principle, this kind of science has the potential to generalize to all of our managed landscapes. We can begin asking questions like, "What does a healthy agricultural microbiome look like?" Thinking across both food and forest agriculture.

然而，除了这些碳和气候结果之外， 我认为这里最令人兴奋的事情 是我们实际上可以用野生和本地以及生物多样性 的微生物组合来做到这一点。 虽然我们在原则上将这种方法指向林业， 但这种科学有可能推广 到我们所有管理的景观。 我们可以开始问这样的问题， “健康的农业微生物群是什么样子的？” 思考粮食和林业农业。

And there's reason to think a biodiversity-first approach may be particularly powerful here. And that’s because the history of agriculture has been an exercise in reductionism. We've identified high-performing plant species, and then strains, and then we’ve selectively bred them, and now we genetically modify them. And finally, we plant those organisms out in vast monocultures. So a single plant species as far as you can see. And to be clear, this has produced very productive agroecosystems. But it's also produced ecosystems we’re coming to understand are remarkably fragile. Systems increasingly sensitive to extreme climate events, novel pathogens. Systems incredibly reliant on chemical inputs, we're coming to understand have really serious externalities.

并且有理由认为生物多样性优先的方法 在这里可能特别有效。 那是因为农业的历史 一直是还原论的实践。 我们已经确定了高性能植物物种， 然后是品系， 然后我们选择性地培育它们， 现在我们对它们进行基因改造。 最后，我们将这些生物种植在广阔的单一栽培中。 因此，就您所见而言，只有一种植物。 需要明确的是， 这产生了非常多产的农业生态系统。 但它也产生了 我们逐渐了解的生态系统非常脆弱。 系统对极端气候事件、 新型病原体越来越敏感。 非常依赖化学输入的系统， 我们开始明白具有非常严重的外部性。

So we now have the data, computational tools and the ecological theory to start going the other way, to lean into biodiversity and complexity. And once we do, the question really becomes, by rewilding our soils, can we make our managed food and forest landscapes reservoirs of belowground biodiversity? And in the process, can we enhance yields and carbon capture and all the other services we ask of these ecosystems?

因此，我们现在有了数据、计算工具 和生态理论，可以开始另辟蹊径，研究 生物多样性和复杂性。 一旦我们这样做了，问题就真的变成了， 通过重建我们的土壤， 我们能否使我们管理的食物和森林景观 成为地下生物多样性的水库？ 在这个过程中， 我们能否提高产量和碳捕获 以及我们要求这些生态系统提供的所有其他服务？

I think there's a lot of reason to be incredibly hopeful here. And I think we also shouldn't be so surprised that these microscopic organisms have the potential for such enormous, ecosystem-scale effects. And that’s because we’ve known now, really for a long time, that forests are fungi. And they’re incredibly biodiverse communities of bacteria and archaea and protists and microscopic soil animals and viruses. Soil is the literal foundation of terrestrial ecosystems, and the microbial life that inhabits soil represents some of the most complex and biodiverse communities of life on Earth.

我认为有很多理由在这里充满希望。 而且我认为我们也不应该对 这些微观生物具有 如此巨大的生态系统规模影响的潜力感到惊讶。 那是因为我们早就知道 森林是真菌。 它们是细菌、古细菌 、原生生物、微观土壤动物和病毒的令人难以置信的生物多样性群落。 土壤是陆地生态系统的真正基础 ，栖息在土壤中的微生物 代表了地球上一些最复杂和生物多样性 的生命群落。

For the first time, DNA sequencing is turning the lights on belowground. It’s allowing us to see these organisms in unprecedented detail and at unprecedented scales. Imagine studying plant biology, but you never really knew if you're looking at a sequoia tree or a sphagnum moss. And then, all of a sudden, you did. That's what's happening right now in global environmental microbiology. And so we should expect this revolution in our understanding of these microscopic organisms, and particularly fungi, to transform how we understand and how we manage our ecosystems in a foundational way.

我认为有很多理由在这里充满希望。 而且我认为我们也不应该对 这些微观生物具有 如此巨大的生态系统规模影响的潜力感到惊讶。 那是因为我们早就知道 森林是真菌。 它们是细菌、古细菌 、原生生物、微观土壤动物和病毒的令人难以置信的生物多样性群落。 土壤是陆地生态系统的真正基础 ，栖息在土壤中的微生物 代表了地球上一些最复杂和生物多样性 的生命群落。