More than a third of the Earth's top layer is at risk. Is there hope for our planet's most precious resource?

地球上超过三分之一的表层土壤面临威胁。我们星球最珍贵的资源是否有希望被保护？

A More than a third of the world's soil is endangered, according to a recent UN report. If we don't slow the decline, all farmable soil could be gone in 60 years. Since soil grows 95% of our food, and sustains human life in other more surprising ways, that is a huge problem.

A 根据一项最近的联合国报告，世界上超过三分之一的土壤正在被破坏。如果我们不减缓这种衰退趋势，所有可耕种的土壤会在60年内消失。由于我们食物中的95%需要依赖土壤，并且土壤在其他更多方面维持人类生命，所以这是一个巨大的问题。

B Peter Groffman, from the Cary Institute of Ecosystem Studies in New York, points out that soil scientists have been warning about the degradation of the world's soil for decades. At the same time, our understanding of its importance to humans has grown. A single gram of healthy soil might contain 100 million bacteria, as well as other microorganisms such as viruses and fungi, living amid decomposing plants and various minerals.

B 来自纽约卡瑞生态系统研究所的Peter Groffman指出在几十年间，土壤科学家一直针对地球上的土壤退化现象发出警告。与此同时，我们归于土壤对人类重要性的理解也在提高。仅一克健康土壤中就可能含有一亿细菌，以及一些其他微生物，如病毒和真菌，他们存在于腐烂植物和各种矿物质中。

That means soils do not just grow our food, but are the source of nearly all our existing antibiotics, and could be our best hope in the fight against antibiotic- resistant bacteria. Soil is also an ally against climate change: as microorganisms within soil digest dead animals and plants, they lock in their carbon content, holding three times the amount of carbon as does the entire atmosphere. Soils also store water, preventing flood damage: in the UK, damage to buildings, roads and bridges from floods caused by soil degradation costs £233 million every year.

这意味着土壤并不是只能用来种植食物，而是几乎所有现存抗生素的来源，并且可能是我们对抗耐药性细菌的最大希望。土壤同样可以帮助我们对抗气候变化：由于土壤中的微生物消化死去的动物和植物，他们可以留住动植物的碳成分，保存相当于整个大气层三倍的碳含量。土壤同样可以贮藏水分，防止洪水灾害：在英国，每年由于土壤退化而遭受洪灾的建筑物，道路和桥梁需要花费2.33亿英镑来修复。

C If the soil loses its ability to perform these functions, the human race could be in big trouble. The danger is not that the soil will disappear completely, but that the microorganisms that give it its special properties will be lost. And once this has happened, it may take the soil thousands of years to recover.

C 如果土壤失去发挥这些功能的能力，人类会陷人巨大的麻烦。这种危险井不在于土壤会完全消失，而在于赋予土壤特殊性质的微生物将会消失。一旦这种情况发生，土壤需要几千年才可以恢复原有的状态。

Agriculture is by far the biggest problem. In the wild, when plants grow they remove nutrients from the soil, but then when the plants die and decay these nutrients are returned directly to the soil. Humans tend not to return unused parts of harvested crops directly to the soil to enrich it, meaning that the soil gradually becomes less fertile. In the past we developed strategies to get around the problem, such as regularly varying the types of crops grown, or leaving fields uncultivated for a season.

到日前为止农业是最大的问题。自然环境下，植物生长时会带走土壤中的营养物质，但随看植物衰退腐烂，这些营养物质会直接返还到土壤中。人类往往不会将所收获庄稼的未使用部分直接返还到土壤中使其更加肥沃，这意味着土壤会逐渐变得越发贫瘠。过去我们使用各种方法避开这一问题，比如定期改变种植农作物的品种，或是在一个季度中不对田地进行耕作。

D But these practices became inconvenient as populations grew and agriculture had to be run on more commercial lines. A solution came in the early 20th century with the Haber-Bosch process for manufacturing ammonium nitrate. Farmers have been putting this synthetic fertiliser on their fields ever since.

D 但是随着人口增加以及农业以更加商业化的方式进行，这些方法变得不再可行。20世纪早期。随着制作硝胺酸的哈布二氏法出现，人们找到了一种解决方法。自此以后农民们将这种合成肥料用在自己的农场里。

But over the past few decades, it has become clear this wasn't such a bright idea. Chemical fertilisers can release polluting nitrous oxide into the atmosphere and excess is often washed away with the rain, releasing nitrogen into rivers. More recently, we have found that indiscriminate use of fertilisers hurts the soil itself, turning it acidic and salty, and degrading the soil they are supposed to nourish.

但是在最近的几十年，人们发现这显然并不是一个非常明智的主意。化肥会向大气中释放污染性的氧化二氮，过量部分则经常被雨水冲走，从而将氮元素带到河流中。最近，我们发现滥用化肥对土壤本身也有很大伤害，使其变成酸性且含盐度高，并且使那些本想被其滋养的土壤出现退化。

E One of the people looking for a solution to this problem is Pius Floris, who started out running a tree-care business in the Netherlands, and now advises some of the world's top soil scientists. He came to realise that the best way to ensure his trees flourished was to take care of the soil, and has developed a cocktail of beneficial bacteria, fungi and humus* to do this. Researchers at the University of Valladolid in Spain recently used this cocktail on soils destroyed by years of fertiliser overuse. When they applied Floris's mix to the desert-like test plots, a good crop of plants emerged that were not just healthy at the surface, but had roots strong enough to pierce dirt as hard as rock. The few plants that grew in the control plots, fed with traditional fertilisers, were small and weak.

E Pius Floris在荷兰经营一家树木护理公司。他是寻求这一间题解决方法的人之一，现在他开始为世界顶级土壤科学家提供建议。他意识到保证树木得到滋养的最佳方式是保护土壤，并且开发了一种有益菌、真菌和腐殖质的混合物来实现这一目的。西班牙巴利亚多利德大学的研究者们最近给些土壤使用了这种混合物，这些土壤由于过度使用肥料被破坏。当他们将 Floris的混合物用在沙漠般的试验区时，长出的作物不仅表层是健康的，根系也发达到可以刺穿岩石般坚硬的泥土。而用传统肥料养成的对照区的植物，则细小貌弱。

F However, measures like this are not enough to solve the global soil degradation problem. To assess our options on a global scale we first need an accurate picture of what types of soil are out there, and the problems they face. That's not easy. For one thing, there is no agreed international system for classifying soil. In an attempt to unify the different approaches, the UN has created the Global Soil Map project. Researchers from nine countries are working together to create a map linked to a database that can be fed measurements from field surveys, drone surveys, satellite imagery, lab analyses and so on to provide real-time data on the state of the soil. Within the next four years, they aim to have mapped soils worldwide to a depth of 100 metres, with the results freely accessible to all.

F 然而，这种方法并不足以解决全球土壤退化问题。为了评估我们在全球规模上可以采取的施，我们首先需要关于每个地方的土壤种类以及它们所面临问题的精确描述。这并不容易。一方面，尚没有一致的关于土壤分类的国际通行体系。在努力统一不同方法的过程中，联合国建立了全球土壤地图项目。来自九个国家的研究者们正在共同建立一张连接到数据库的地图，它可以获得来自实地考察、无人机考察、卫星影像、实验室分析等方式的测量数据，以提供关于土壤状态的实时数据。在未来四年中，他们的目标是绘制世界范围内深度在100米以内土壤的地图，并将结果免费提供给所有人。

G But this is only a first step. We need ways of presenting the problem that bring it home to governments and the wider public, says Pamela Chasek at the International Institute for Sustainable Development, in Winnipeg, Canada. 'Most scientists don't speak language that policy-makers can understand, and vice versa.' Chasek and her colleagues have proposed a goal of 'zero net land degradation'. Like the idea of carbon neutrality, it is an easily understood target that can help shape expectations and encourage action.

G 但这仅仅是第一步。我们需要呈现问题并使政府和更广泛的公众了解这一情况的途径，来自加拿大温尼伯国际可持续发展研究所的 Pamela Chasek说。“大多数科学家说的并不是政策制定者们能够听得懂的语言，相反政府人员说的话他们也无法理解。Chasek和她的同事们提出了“零土地净退化”的目标。就像碳平衡的想法一样，这是一个非常容易被理解的目标，可以帮助人们描述预期并鼓励行动。

For soils on the brink, that may be too late. Several researchers are agitating for the immediate creation of protected zones for endangered soils. One difficulty here is defining what these areas should conserve: areas where the greatest soil diversity is present? Or areas of unspoilt soils that could act as a future benchmark of quality?

F对处于衰退边缘的土壤，这些或许都为时已晚。几位研究者呼吁马上建立针对濒危土壤的保护区。这里的一个困难是界定这些地区应该保护什么：呈现出最高土壤多样性的地区？还是有未受破坏的土壤可以作为未来质量标准的地区？

Whatever we do, if we want our soils to survive, we need to take action now.

无论我们做什么，如果我们希望土壤得以存活，我们需要当下就采取行动。

* Humus: the part of the soil formed from dead plant material

* 腐殖质：土壤中由死亡的植物物质形成的部分。