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Trees are not enough

City planners often don’t pay enough attention to China’s natural heritage, says Jiang Gaoming. Losses to rural ecosystems, he argues, are not worth the appearance benefit in urban areas – which need their own native biodiversity.

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Sustainable urban development in China depends on both the control of pollution and the protection of biodiversity. The importance of the former is now widely accepted, but the latter is still ignored, even by city planners. The wonders of Beijing’s culture are intimately linked with its biodiversity. Central Beijing has 226,000 old-growth trees, and there are 180,000 more in its suburbs. The city is surrounded by rich and diverse ecologies. Baihua Mountain and Wuling Mountain have 1,200 species of higher plants – a natural heritage more precious than any building. London, New York, Paris and Berlin do not have this kind of rich environment. Yet this natural heritage goes ignored.

The planting of trees on urban pavements has not taken ecological factors into consideration and is clearly artificial, monotonous and unreasonably spaced. In city centres, the large numbers of tall buildings and trees lining the streets prevent the flow of air, while in the suburbs more trees are needed. A sad sight, indeed, is the concreting over of the base of the trees, preventing the growth of bushes and grass. The needs of small mammals and birds are not considered. Poplars monopolise the streets of our northern cities – but where are the indigenous shrubs and plants? There is no canopy coverage and lifespan is short, with trees discarded within a couple of decades. There is no consideration of biodiversity.

Cities need to plan for long-term preservation – the older they are, the more valuable. When designing the imperial resort of Chengde, Emperor Kangxi ordered that all existing vegetation be retained. Tragically today’s city planners use only a few commercial varieties, and cities lose their native biodiversity. So some planners turn their eyes to surrounding villages and buy up large trees in great numbers. This means great business for the tree traders, but disaster for trees in rural areas. (In the worst case, rural trees literally fueled the steel-production drive of the Great Leap Forward.) The trend started in Shanghai and spread nationwide, and now almost every city beautification project ships in truckloads of large trees.

One city brought in over 6,400 trees -- each of more than 30cm in diameter -- at a cost of RMB 10,000 apiece. A single tree changed hands for RMB 220,000. Another city purchased large numbers of mature trees from villages and plantations in an attempt to be named a “National Park City” – but before long over 70% of them had died off. A north-eastern city launched a program to transplant 300,000 trees from villages within two to three years. These schemes cause a number of problems. 

First, they cause serious damage to rural ecologies and biodiversity. Each tree forms a complete ecosystem with its soil, organisms in the soil, surrounding vegetation and birds, mammals and insects. The amputation of the tree destroys that ecology. Soil and water are lost, animals lose their home – losses that are not worth the benefit to appearance of our cities. The removal of a tree 30cm in diameter also results in the loss of one to two tons of soil. Many older villagers complain that they no longer recognise their birthplace.

Second, huge numbers of trees die during transportation. The cutting of root systems, stripping of leaves and long-distance transportation means 50 to 70% of trees die before they reach their intended destinations. And even if they do survive, what value is there in a mighty tree becoming little more than ornamentation?

Third, the process is part of poorly considered projects which value form over substance. Trees grow slowly. Two decades ago, many specialists suggested tree plantations for future use in cities – but nobody paid any attention, leading to today’s tragedies. Improvement depends of us realising that there is no easy solution; using these large old trees as a quick, green fix is a typical example of projects operated for appearance only. This has led to a lack of tree plantations for the purpose of ornamentation, and those that do exist now have to compete with tree speculators. 

Fourth, it leads to corruption and crime. The high cost of bringing trees to the cities mean that there is profit to be made. These large trees have become a commodity, and we now see tree scalpers traveling between villages, seeking a quick profit. Investigations have show that a century-old pear tree can be bought locally for under RMB 100, and a crane to remove it hired for RMB 200 an hour – but get it to the city, and it’s worth over RMB 10,000. Where the money goes is clear. The potential for profit is too high for city officials to resist. 

Fifth, the trees bring diseases and pests, which originally were part of a balanced ecosystem where their natural enemies kept them in check. But when the trees are brought into the cities, disease and pest populations explode. This has caused rises in the numbers of various insects in the cities.

Urban biodiversity needs to be approached scientifically. Local ecosystems need to be preserved, with plants selected from surrounding areas to be moved into the cities where they should form self-sustaining communities. Simply trucking in trees is inadequate.

 

The author: Jiang Gaoming is a professor at the Chinese Academy of Sciences’ Institute of Botany and a doctoral candidate tutor, vice secretary-general of the United Nations Educational, Cultural and Scientific Organisation’s China-MAB (Man and the Biosphere) Committee and member of the UNESCO MAB Urban Group. He is recognised for his introduction of the concepts of urban vegetation and using natural forces to restore China’s ecosystems.

 

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Default avatar
匿名 | Anonymous

没有捷径

这篇文章很好地指出一个问题,一旦没有了长成的大树,就没有简单或快速的解决方法。我认为我们需要用更多更严厉的惩罚来禁止砍树。我住在伦敦,这里是严禁砍树的,即使是自家花园的树,除非它会造成危险。难道中国没有像这样的法律吗?

no quick fixes

This is a fascinating article that show that there are no easy or quick solutions once old growth trees have gone. What it suggests to me is that we need much stricter penalties for cutting down trees. I live in London where it is against the law to cut down a tree, even if it is in your own garden, unless it has become dangerous. Does China have any laws like that?

Default avatar
匿名 | Anonymous

文章标题有问题

这个标题不太合适。通读全文,应该是讲用“大树进城”的方法来增加城市生物多样性是错误的,而不是说“大树进城”远远不够。建议改为:《“大树进城”——增加城市生物多样性的误区》。妥否?请作者考虑。

Suggestion to improve the title

I suggest a better title to the article. After reading the article, I think the title should be "It is wrong to try to increase urban biodiversity by just planting trees" instead of that "trees are not enough". Please consider my suggestion.

Default avatar
匿名 | Anonymous

关于帖文的翻译

“大树进城”翻译成just planting trees太不妥当,应该是“moving the big trees from the villages to the cities"。文章的标题也错在这里。

Suggestions about translation

It’s inappropriate to translate “大树进城”into “just planting trees”, it should be “moving big trees from the villages to the cities”. The article title is also wrong in here.

Default avatar
匿名 | Anonymous

关于标题翻译

谢谢2号评论员建议。我原来用的题目是“增加城市生物多样性不能靠大树进城”,翻译的时候改成了现在的题目,看来现在的题目容易引起误解。大树进城是笔者反对的,因此不是希望越来越多,而是要禁止。

Re: title translation

Thanks to the author of comment No. 2 for your suggestion. My original title is "Transporting trees into cities is not the way to increase biodiversity", but the title was changed when translated. It seems that this has resulted in a misunderstanding. What I am opposed to is transporting trees into the cities. This should be forbidden, I am not in favour of trucking in more.-- Gaoming Jiang

Default avatar
匿名 | Anonymous

回复:标题翻译

我们已经将认真考虑过您的建议,并对标题做了修改。如果您认为我们的文章有任何翻译上的错误,欢迎随时指出,请直接联系我们,邮箱地址是[email protected] Chinadialogue

Re: title translations

Hi - we have been trying to take your comments into account and have published a modified chinese title.
If you suspect something has been mistranslated please feel free to email us directly at [email protected]
Sam - chinadialogue

Default avatar
匿名 | Anonymous

英文标题是否也应该改过来?

谢谢你们的更正。但英文标题是否也应该做一下相应的修改?

Should the English title be revised?

Thanks for your kind correction. And should the English title be revised?

Default avatar
匿名 | Anonymous

大树搬家

据我所知,在云南的一些绿化公司,通常的做法是把在云南南部热带雨林里的一些长势良好的大树拍好照片,到城市兜售,客户看中哪棵,就到森林里去移植哪颗,通常这些行为都是当地林业管理者和商人共同操作的

Moving forests across Yunnan

As I understand it, some forestry companies in Yunnan take photos of thriving big trees in the tropical south part of the province. After that, they show these photos to their clients in the city. Once decided by the client, they go back to the forest to dig them out and move them to the cities. Generally speaking, these arrangements are conspired by the local forestry regulators and businessmen.

Default avatar
匿名 | Anonymous

关于树的法律

和伦敦相比,中国的树大多是没有树权的,即使活了上百年的大树。作为发展中国家,中国人基本上还没有为树立法的观念。

Laws regarding trees

Compared with in London, China's trees have very few rights and little protection under the law, even if they have been living for hundreds of years. As China is a developing country, Chinese people still do not have an idea of laws protecting trees.

Default avatar
匿名 | Anonymous

谁决定了要买这些大树?

这在很大程度上已经不是一个环境问题,而是政治问题。谁决定了要买这些大树?是那些有巨大贪污才能的官员。这些大树不过是他们的摇钱树。

Who decided to buy these trees?

For the most part, this is not an environmental problem, but a political one. Who decided to buy these trees? It's those officials involved in major corruption who do it. These trees are a ready source of money for them.