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"A sea of plastic"

Short-term profit motives have led China’s farmers to use polluting plastics, chemical fertilisers and herbicides in abandon. The country needs sustainable farming to preserve the quality of its food – and its land, writes Jiang Gaoming.

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During my recent visits to villages in the Chinese provinces of Henan, Hebei, Tianjin and Shandong, I saw the phenomenon of “white pollution” with my own eyes. This “white terror” is the sea of plastic that covers our land and blows on the breeze along the highways.

This plastic membrane used in agriculture can be seen strewn between fields, in ditches and beside roads – you even see it on streets in towns and in household courtyards, piled layer upon layer. I have visited dozens of countries, but never seen plastic used on such a scale as it now is in China. And it looks as if the country’s five millennia of agricultural history may now be destroyed by the excessive use of plastic membrane, fertiliser, pesticides and herbicides. 

Plastic has two main uses in farming – to construct plastic greenhouses for growing crops out of season, and covering the ground to increase the value of crops. In the provinces of Shandong and Hebei, I saw it used to grow almost every crop, apart from cereals like wheat and maize. Peanuts, potatoes, watermelons, garlic, eggplants, peppers and tobacco are all grown under plastic.

The farmers say that covering the ground with a plastic membrane increases the temperature and humidity of the soil, extending the growing season and increasing harvests by 20% to 50%. When growing crops such as peanuts, they say, it can even double production. This method of farming may be a new scientific advance, but nobody has considered whether our environment can cope with the plastic waste that results. Currently, about half a million tonnes of the plastic is left in the soil every year, almost 40% of the total plastic used. This forms a layer in the earth which is less permeable to water and air, making it harder to farm.

More careful farmers will remove the membrane from their fields at the end of the growing season, but they only go so far as to throw it to the edge of their land. The plastic is light and covered with earth, so it is difficult to sell for recycling. When there is a big enough pile of the stuff, the farmers generally burn it – polluting the environment even further.

Plastic can be seen across China's fields

Organic compounds which do not biodegrade are known as Persistent Organic Pollutants (POPs), and 12 of the most harmful of these chemicals were restricted or banned by the 2004 Stockholm Convention on POPs. These compounds linger in the environment for long periods and can enter the human body through food or respiration, causing poisoning, cancers and even death. Burning plastic membrane results in the release of at least five of the 12 POPs listed by the Stockholm Convention.

Ten years ago, officials from the Ministry of Agriculture and Ministry of Science and Technology expressed hopes that scientists could develop a microorganism to break down plastic waste – but there has been little success. Despite frequent and promising-sounding reports to the contrary, these methods are expensive and ineffective, and the farmers simply do not use them. Officials and their scientists have both made a fundamental error: plastic is not something that can be dealt with by the natural world. The solution is to look for an alternative material or use policy measures to stop its use, and control the pollution at the source.

While it may be true that the large-scale use of plastic membrane increases production, it also lowers quality. All living organisms will suffer and lose quality if you force them to grow in an unnatural manner, such as cultivating them very rapidly. It can mean a loss of flavour, as well as pollution in the fields. Thanks to the use of plastic membrane and fertiliser in agriculture, I have seen garlic shoots thicker than my thumb – impossible 20 or 30 years ago – but the farmers themselves will tell you that the flavour is not the same. In the past, garlic would be covered with straw and natural fertiliser, but now plastic membrane and chemical fertilisers are used, and the taste has suffered.

Some will say that since the harvests are bigger, the farmers can earn more. But in reality, the extra income is divided up among other parties, with little left for the farmers themselves – even though they bear the risks. In practice, the merchants who sell the plastic, exporters, wholesalers, local traders and retailers all want to divide the extra income. Extra earnings that come from waiving agricultural taxes or from increased subsidies are quickly swallowed up by increases in the cost of raw materials – and the farmers are left to deal with the pollution. They remain at society's lowest level, and never earn as much from greater harvests as they can by leaving the land and working in the cities. In one area, I saw the price of garlic shoots drop from 1 yuan (US$0.15) a kilogram to 0.6 yuan over the course of two days. Last year, freshly-picked garlic sold for 2.4 yuan a kilogram; this year it only fetches 1.4 a kilogram. With every household planting the same crops, the farmers are unable to withstand the market risk.

Covering the ground with plastic and chemical fertiliser is comparable to feeding it with opium: crops grow bigger and faster, but the land becomes unhealthy and reliant on artificial support. Nowadays, farmers often say that nothing will grow without lots of fertiliser. The plastic, fertiliser, pesticide, herbicide and additives accumulate in the soil and sap its vitality in the long term.

Farmers rely on the land for their living, and it is vital that we protect the land, rather than encouraging farmers to use unnatural methods for the sake of short-term profit. Yet the widespread use of plastic membrane has been promoted by the Ministry of Agriculture and government.

Instead of turning the earth white with plastic, we should be using organic material to make it darker: feeding straw to livestock to produce meat, milk and dung. This dung can subsequently be used to produce methane, and the residue can fertilise the fields. Increasing the organic content of the soil and improving its structure will allow high levels of sustainable – rather than short-term – production. Livestock and energy production will be increased, and the value added to the land will be much greater than using plastic. The use of organic fertiliser will reduce the volume of chemical fertilisers used, and eliminating the use of plastic will reduce costs and put a stop to this “white pollution”. These are all needed to provide a healthy path forward for China’s agriculture, and must be considered by the Ministry of Agriculture, the State Environmental Protection Administration (SEPA), Ministry of Land and Resources and the Ministry of Science and Technology.

Farmers’ income must be increased through appropriate measures, with increased production and increased efficiency going hand in hand, the land being protected and pollution reduced. Short-term methods such as the use of plastic membrane exploit the land without caring for it. In fact, these methods destroy the land – and should be discontinued altogether.


Jiang Gaoming is a professor at the Chinese Academy of Sciences’ Institute of Botany. He is also vice secretary-general of the UNESCO China-MAB (Man and the Biosphere) Committee and a member of the UNESCO MAB Urban Group.

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Default avatar
匿名 | Anonymous

引导而不是禁止

引导群众使用生物降解地膜,而不是禁止使用高科技产品,解决白色污染问题。

Guiding instead of banning

In solving the problem of "white pollution", we should guide the public in using microorganism to break down plastic waste, instead of banning the use of high-tech products.

Default avatar
匿名 | Anonymous

从我们自己做起

要阻止这种糟糕的情况恶化,政府之间必须密切合作,言行一致.但是,只要求政府采取行动是不够的,作为个人我们也必须行动起来,尽我们的能力让地球再披绿装.

We must start with ourselves.

To prevent this nightmare of having no usable infield from coming true, governments need to work closely with each other and back up their verbal commitment by actions. However, it is not enough only to ask what governments can do to get rid of white pollution, we must ask ourselves what we as individuals can do to colour the earth green instead of white.

Default avatar
匿名 | Anonymous

我想问问

我想问一下,农膜也算是白色污染吗?

One question

Hi there, may I ask if the plastic membrane counts as white pollution?

Default avatar
匿名 | Anonymous

农膜和白色污染的关系

传统的农膜多数是塑料膜,这种膜不能够降解,多季使用后留在土壤里对土壤质量、透水性等都有影响,如果焚烧则会产生有毒物质直接污染土壤、空气和水源。
现在有新研发的可降解农膜,但是价格高。

真让人头疼,耕地资源本来就有限,如果不保护好土壤,将来吃什么,作者身居其位,请多多向有关部门建言啊。

李阳
慕尼黑工业大学

The relationship between White Pollution and Plastic Membranes

The majority of membranes used for farming have traditionally been made from plastic, a material which is not degradable. They are left in the ground for many seasons and so influence the quality of the soil, its water permeability, and so on. If the membrane is exposed to fire, it produces harmful chemicals which directly pollute the nearby soil, air, and water sources. Although new research is being done regarding degradeable membranes, the cost is steep. This issue really is a headache as our agricultural resources are already limited, and if we don't protect good soil, what will we eat in the future? Please would the author present their opinions to the relevant departments as much as possible.
Li Yang, Technical University of Munich.

Default avatar
匿名 | Anonymous

献给蒋先生和热爱这片土地的人

有一技术“地膜覆盖无孔种植法”,简称[新膜法],可免除耕地的白色污染。
地膜覆盖种植法在我国应用已近二十年,用地膜覆盖表土,地膜两边各垂直埋入土中十余厘米,将土壤分成膜内外,在地膜上面开孔,种庄稼。因地膜埋入土中太多,又与作物根结合在一起,极难回收。
地膜覆盖无孔种植法,用地膜平铺于表土,边沿用土压紧封闭,将庄稼种在地膜旁边,膜下土壤中的水分和热量不易散失,却容易吸收外界水分,因此,庄稼增产不比传统覆盖法少。因地膜无深埋土中的部分,庄稼和地膜完全分离,地膜可全部回收。做到了既使用地膜,又不让地膜对耕地造成破坏。新膜法使用的地膜是旧地膜覆盖种植法的一半(地膜宽是旧地膜的一半),特点是节能减排。
提议
农村的地膜污染十分严重,年复一年的地膜复盖种植,年复一年的把一半以上的地膜混入土壤中,虽获得眼前的高产,却在慢慢地毁掉赖以生存的耕地,真是“医的眼前疮,剜却心头肉”!地膜污染每一寸土地,每一个空间。农民把田里的地膜扔到地头、沟、坡,这些地方本来是留给野生植物的生存之地,长点杂草供牛羊吃,现在不能了。电线、树枝、灌木上、草梗上缠满了地膜。让人看了既恶心又惊心!
我国的农民本来是不会使用地膜的,为了提高粮食产量,政府推广使用旧地膜种植法,粮食产量上去了,但可怕的白色污染也随之而来。
我们不应只满足于眼前粮食产量的提高,更应实现人与环境和谐相处,更应珍惜我们赖以生存的耕地,耕地不仅是农民的,更是全体人民的命根子,我们的衣食来自土地。我们应当像推广旧地膜覆盖种植法一样,推广新膜法,须知,习惯势力是强大的,农民习惯了旧地膜覆盖种植法,绝不敢使用新膜法,靠新膜法自然传播到全国,所需的时间太长了,可能需要几十年,甚至半个世纪。那样长的时间里,地膜污染给我们造成的损害是无法挽回的!
zhangftacz ([email protected]

To Mr. Jiang and those who love our land

There is a technology by the name of Imperforate Film Mulching Method for Crop Planting, simply as 'New Film Method', which can save arable land from white pollution. Nearly 20 years has witnessed the Chinese application of film mulching method, by which the topsoil is covered with plastic film in a way that both ends of the film, as a separator to keep the inside soil from the outside one, are buried perpendicularly into the soil, and through the opening on the film, the crops are planted. Because the film is buried too deep into the soil and entangles with the crop roots, it is hard to recycle them. In contrast, the imperforate film mulching method is a way to cover the topsoil with the film fixed by compacted soil on its ends when the crop is planted beside the film. By this method, the soil under the film is easy to keep moisture and heat, and is easy to absorb external moisture as well, which makes the crop growth not less than that by traditional mulching method. As the film is not buried deep into the soil, the crop and the film are separated from each other completely and the film can be all recycled, which stop the film from damaging the arable land while putting it in use. The film used in new film method is half of that in old method(half of the old film in width) with features of energy saving and emission reduction.

Suggestions:

the rural pollution by film is grim after the old method being taken, and more than half of the used film being mixed with the soil year after year. the old method is gradually destroying the arable land we live with even though it brings current high yield, which is really a gain for now but a loss in future! the film dirties our land and space when farmers throw them onto the ground, ditches and ramps beside their farmland. These are places for wild plants like weed that fits for cows and goats, but they are now unavailable. The scene of film entangling with powerwires, tree branches, shrubs and straws is disgusting and astonishing! To raise the food production, governments promote the old method that Chinese farmers had no idea of using them at first, and this results in a rising yield followed by the horrible white pollution. comparing with the happiness of the rising production, we should pay more efforts to come true the harmony between man and nature, and cherish more the arable land we live by. the arable land is a life line not just for farmers but for the whole nation because our clothes and food are made from it. It is needed to promote the new film method the way the old method was promoted, as the old habit of taking the old method by farmers dies hard. It will take too long a time of decades or even half a century to spread the new film method nationwide if we let the method run its own promotion. In such a long time of self-promotion, the film pollution will do a damage we can not reverse! zhangftacz ([email protected]

Translated by Ming Li

Default avatar
匿名 | Anonymous

3年后的现状

尊敬的蒋教授,
3年后,由于朋友的介绍,网络搜索,看到了您的这篇很有前瞻性的评论。
3年后的现状,我们可以看到,新疆已经由于不当的使用塑料地膜,出现水处理的问题。
PE塑料农膜,可回收的PE 塑料农膜被堂而皇之的成为可降解薄膜,继续在农田里四处使用。
由于成本低廉,又可以达到最直观的效果,很多农民依然使用这些低廉的塑料垃圾,用起来恶心,吃到百姓肚子里,更加恶心。
我们一直在抱怨现在的番茄,没有番茄的味道了,现在的黄瓜也没有黄瓜的味道了。
3年前的评论,到现在为止,依然没有得到有关部门的有力地科学正确的引导。
现在欧美国家都已经在致力推广100%生物可降解农用地膜的同时 ,中国上海还原高分子有限公司也将成为他们原材料的最大供应商,可是在国内,由于生产成本和价格因素,国内市场依然无法顺利打开局面。
只能用鲁迅先生的话说一句,人血馒头来治病,PE 环保塑料可降解农膜来种地一样。
中国需要科普,农民的杀鸡取卵的方法,和那些奸商为了蝇头小利,恶意误导毁掉我们赖以生存,息息相关的沃土,这些不道德的行为,都是需要用科学知识和国家的权威机构来引导的。
sophia yeh [email protected]

The situation 3 years later

Dear Professor Jiang,
3 years have passed and, thanks to a friend's suggestion, I browsed the net and saw your farsighted critique. As we can note, the situation after 3 years sees Xinjiang dealing with water treatment problems as a consequence of the inappropriate use of plastic membranes in the fields. The recyclable PE plastic membrane used in agriculture will largely become biodegradable and continue to be used everywhere in the rural areas. Because of its cheap cost and the possibility to achieve more visible results, many peasants still employ this cheap plastic garbage, only to feel disgusted when they use it, nauseous when it reaches their guts. We always complain that today's tomatoes don't taste like tomatoes, today's cucumbers don't taste like cucumbers.
Up to now, this criticism hasn't spurred yet a proper strong guidance by the concerned departments. While Europe and America already devote themselves to popularize 100% biodegradable plastic for agricultural use, Shanghai Reduction of Polymer Materials Company Ltd. will become their main raw material supplier, but in China, due to the manufacturing costs and prices, the market is not ready for that phase yet. We can use Lu Xun's saying: just as human blood bread can cure illnesses, environmental protection PE biodegradable plastics can be used to cultivate.
China needs a popularisation of science, because the immoral conducts we find in the stupid manners of peasants or in the petty profit-lead unscrupolous merchants will destroy the fertile soil we can't live without. They need to be guided by scientific knowledge and authority organs.