【经济学人】清洁能源与生态 [英国媒体]

Clean energy and ecology

清洁能源与生态

Offshore wind farms will change life in the sea

海上风电场将改变海洋生物

Flexing the mussels

贻贝展示力量



IN THE North Sea, wind power is booming. At the moment the world’s biggest offshore wind farm, with a capacity of 630MW, sits in the Thames Estuary. But the London Array, as this farm is known, will not hold the record for long. Another farm, over twice the size, is under construction off the coast of Yorkshire. Of the six countries with the most installed offshore capacity, five are part of the North Sea’s littoral. (The exception is China.) Bloomberg New Energy Finance, a research firm that keeps a close eye on the industry, reckons the world’s offshore wind-generation capacity will quadruple by 2025.

在北海，风能正在迅猛发展。目前全球最大的海上风电场坐落于泰晤士河口，装机容量630兆瓦。但这座名为“伦敦阵列”的风电场的世界纪录不会保持太久。在约克郡沿海，另一座风电场正在建造当中，面积是其一倍。在海上风电装机容量最大的六个国家中，五个是北海沿岸国家（中国例外）。“彭博新能源财经”调查公司密切关注该产业的发展，预测2025年全球海上风电容量将翻两番。

Given the need to cut carbon emissions, that is welcome news. But, just because wind turbines produce little carbon dioxide does not mean they have no environmental impact. In a study posted on the arXiv, an online repository of scientific papers, Kaela Slavik and her colleagues at the Helmholtz Centre for Materials and Coastal Research, in Geesthacht, Germany, explore the effects that the turbines might have on local wildlife.

鉴于减少碳排放的需要，这条新闻令人高兴。但风力涡轮机不排放二氧化碳不意味着对环境没有影响。凯拉•斯拉维克及其同事任职于德国盖斯特哈赫特的“赫尔姆霍茨材料与海岸研究中心”，她们在科学文献库arXiv网站上发表的研究报告中，探讨了风力涡轮机对当地野生动物可能产生的影响。

As every sailor will tell you, almost anything immersed in seawater for long enough will be settled by living creatures. Wind turbines—or, rather, the concrete pilings upon which they sit—are no different. Turbines in the North Sea provide a particularly enticing home for a type of tasty, edible mollusc called the blue mussel. FINO 1, a German research platform, for instance, was found to have an average of 4.3 tonnes of mussels clinging to each of its four piles. Dr Slavik and her colleagues wondered what might happen as more and more turbines proliferate across the North Sea.

但凡水手都知道，几乎任何东西在海水里浸泡久了，都会有生物寄居在上面。风力涡轮机也是这样，更确切的说是支撑它们的混凝土桩。北海的风力涡轮机为一种美味、可食用的软体动物提供极具吸引力的家园，它被称为紫贻贝。例如：在FINO 1德国科研平台的四根基桩上，平均每根挂有4.3吨贻贝。斯拉维克博士及其同事想弄清楚，随着日益增加的风力涡轮机遍布北海，有可能发生什么。

One thing seems certain: there will be plenty more mussels. The team calculate that, if all the wind farms currently planned for the North Sea are built, they will provide extra habitat equal to about a fifth of the naturally occurring mussel beds along that sea’s coasts.

有一点看来确定无疑：贻贝会越来越多。该团队估算，如果目前规划的北海风电场全部建成，增加的栖息地面积约为海岸上天然的贻贝聚生地的20%。

This will have consequences. Mussels eat plankton that they filter from the surrounding water. Dr Slavik’s computer modelling suggests plankton numbers around wind farms could fall by as much as 10%. Since plankton are at the start of most marine food chains, that will mean less of them for other animals, such as anemones, scallops and jellyfish, and thus less of those species and others that in turn depend on them. It will, however, mean more food for species that eat mussels, of which there are many—starfish, seagulls, seals and, not least, people, especially Belgians, who have already set up an experimental mussel farm on one of their wind farms.

这将产生后果。贻贝以周围海水中的浮游生物为食，斯拉维克博士的计算机模拟显示，风电场周围的浮游生物可减少10%。由于浮游生物是多数海洋生物链的起点，这意味着其他动物得到的浮游生物会减少，例如海葵、扇贝、水母，结果这些物种和以它们为食的其他物种也会减少。然而，这意味着以贻贝为食的物种会有更多食物，这类动物有很多，例如：海星、海鸥、海豹，尤其是人类，比利时人在其中一座风电场上建造了贻贝实验养殖场。