Human footprint shows extinction, climate change steps

[MANILA] Halting or reversing the effects of carbon dioxide and other planet-warming greenhouse gas emissions is best done by using the human footprint to identify key regions where action can be the most cost-effective, says a new study.

根据study, published last month (October) in自然, restoring a select 15 per cent of the land converted or degraded by humans could avoid 60 per cent of expected extinctions while sequestering 299 gigatonnes of carbon dioxide, or the equivalent of 30 per cent of the total carbon dioxide increase in the atmosphere since the Industrial Revolution.

根据World Economic Forum,over halfof the land on earth has been converted by human activity.

恢复世界上30％的退化土地到其自然状态，可以挽救70％以上的土地哺乳动物，两栖动物和鸟类有可能死亡的风险，同时吸收超过4650亿吨的二氧化碳。

“协调不同类型生态系统的恢复工作将带来最大的总体好处。”

Hawthorne Beyer, University of Queensland, Australia

Most of the priority areas identified are in developing countries and tropical regions, specifically South-East Asia, South Asia, Central and South America as well as West and Central Africa.

“这个研究对于在国际政策层面上为战略决策提供信息特别有用，”Hawthorne Beyer，一个研究员University of Queensland在澳大利亚和研究的合着者，告诉scidev.net。

“However, achieving restoration in practice requirescooperationamong countries to share the costs of restoration, and the development of national and regional programs that encourage land owners to participate in restoration activities and that compensate them for lost revenue — an idea known as 'payment for ecosystem services’.”

为了帮助确定优先领域，研究人员分析了全球28.7亿公顷的生态系统，这些生态系统已在1992年至2015年之间转换为农田。然后，他们根据三个主要动机评估了土地 - 通过增加栖息地的降低风险，增加栖息地的灭绝风险气体以及由于生态系统恢复而对农业生产的影响减少。

“Not every natural ecosystem will be optimal for climate and生物多样性, and even fewer areas are great for both benefits and not so much for agricultural production simultaneously,” Alvaro Iribarrem, a researcher and professor at the里约热内卢教皇天主教大学，巴西和研究的合着者告诉scidev.net。

Further complicating the challenge of identifying priority areas is that “restoration must not impact18beplay in the context of a growing global population over the coming decades”, adds Beyer.

After factoring in the various costs and benefits, the researchers found that restoring森林and wetlands delivers the highest climate and biodiversity benefits, while restoring grasslands and arid ecosystems costs the least.

In particular, 96 per cent of the Caribbean converted lands are in the top 15 per cent of global priorities for biodiversity. Restoring South American and African shrublands, meanwhile, brings important benefits for their unique biodiversity.

拜尔在向记者讲义中说：“协调不同类型生态系统的恢复工作将带来最大的总体好处。”

道格拉斯·莫尼（Douglas Muchoney），负责人FAO的地理空间单位告诉scidev.net，这项研究是有益的，“对于当地生态学的更多理解，一个起点。”但是他强调，为了有效地解决生态系统恢复，尤其是与全球挑战有关的情况，包括SDGs一般而言，科学家需要将生态系统视为一种抽象，而更像是具有独特风景的真实地方，以及所有需要的复杂性。

“我们必须预料昆虫，病原体和人和政策，“ 他说。

这件作品由Scidev.net的亚太桌子制作。