从为风暴多发的海岸遮风挡雨的红树林到锁住数万吨碳的泥炭地，再到赋予生命的土壤景观：地球的生态系统具有巨大的价值。但这一价值很难衡量，而且经常被忽视——对环境造成了严峻的后果。
联合国环境署的报告《成为#修复一代》 发现，全球一半的GDP依赖于自然，对于生态修复每投资1美元就会创造高达30美元的经济效益。
现在，可以使用新的工具来衡量自然的价值及其对人类的诸多好处，使政府和其他决策者能够将地球的“自然资本”与人类和人造资本一同考虑，并加紧对于自然资本的修复。
“气候变化、生物多样性丧失和污染证明，狭隘地一味追求传统经济增长无法为我们自身和子孙后代提供想要的生活质量，”联合国环境署首席环境经济学家普什帕姆·库马尔说。 “在我们向可持续发展转型的过程中，我们必须将地球的所有馈赠都考虑在内。”
长期以来，经济发展一直由一国的国内生产总值 (GDP) 来衡量。每年计算一次，GDP反映了一国商品和服务产出的市场价值总和。
但专家表示，这一指标缺乏对环境退化的关注，导致经济政策和投资转向了有害的方向，包括对化石燃料的依赖和日益加剧的不平等，以及对地球有限资源的不公平和不可持续利用。
“我们现在面临的关键决策，例如能源系统转型和生物多样性保护，需要通过比GDP更好的指标来衡量”库马尔说。
Climate change, biodiversity loss and pollution prove that a narrow focus on conventional economic growth cannot deliver the quality of life that we want for ourselves and future generations.
The shortcomings of GDP
GDP captures some of the most tangible ways that nature contributes to the economy, such as supplying markets for timber and fish. But it largely omits nature’s “non-market” benefits, including its spiritual, aesthetic, or recreational value. Also overlooked are fundamental functions such as the generation of fertile soil, the provision of clean air and water, and natural barriers to disease.
Moreover, Kumar notes that market mechanisms typically fail to reflect the alarming erosion of the natural capital from which these vital benefits flow, such as the loss of forests and wetlands or the pollution of the atmosphere.
“This conceals how the foundations of human well-being are weakening even as financial incomes may have risen for most people,” he said.
In response, economists are developing new ways to measure wealth and well-being that better reflect the health of the planet as well as of people and economic systems. More governments have begun to use these metrics to guide their development strategies and economic policies.
New yardsticks for sustainability
For example, UNEP has developed the Inclusive Wealth Index (IWI). Rather than focus on flows of goods and services, the index sums the social value of economic, human, produced and natural assets to indicate whether countries are developing sustainably.
Now calculated for about 140 countries, the index indicates that inclusive wealth expanded by an average of 1.8 per cent for the 1990-2014 period, far below the 3.4 per cent expansion rate of GDP, largely because of declines in natural capital.
“The index doesn’t just show that we are not as wealthy as we think we are,” adds Kumar. “It shows how protecting or restoring the environment is as relevant as developing industries, expanding education and improving public health for our long-term prosperity.”
Natural capital accounting
Countries are also going beyond GDP by adding environmental statistics to their national accounts. Under the UN-supported System of Environmental Economic Accounting (SEEA), countries can track environmental assets such as energy and water resources, their use in the economy, and return flows of waste and emissions.
An assessment in 2020 showed that 89 countries have already implemented the SEEA and another 27 plan to join them.
To further strengthen natural capital accounting, the SEEA has expanded to include “ecosystem accounts” that measure the diversity, extent, condition and the value of ecosystems and the services they generate. Once fully developed, the accounts can reveal how ecosystems as a whole support an economy and whether they are being depleted. “This is a historic step forward towards transforming how we view and value nature,” UN Secretary-General António Guterres said at the 2021 launch. “We will no longer be heedlessly allowing environmental destruction and degradation to be considered economic progress.”
Dozens of countries are already compiling ecosystem accounts on an experimental basis. In South Africa, for example, a study using ecosystem accounts has shown that the economic benefits of restoring grasslands degraded by erosion and bush encroachment clearly outweigh the costs.
Researchers are working on biophysical modelling and artificial intelligence tools to generate ecosystem accounts automatically – a boon for countries with limited data and resources for the task.
This new way of taking nature into account is also starting to affect businesses. The new ‘Task Force on Nature-related Financial Disclosures’ will provide the metrics for the private sector to calculate and manage their ecological footprint.
Monitoring restoration
Ecosystem accounts could also guide growing efforts to halt and reverse environmental degradation.
Coordinators of the UN Decade on Ecosystem Restoration, which began in 2021, are exploring how ecosystem accounts can help identify degradation hotspots and monitor the long-term impacts of projects to restore them. The SEEA could also be used to measure countries’ progress – or lack of it –toward the Sustainable Development Goals and new post-2030 global biodiversity targets to be set later this year. Countries have already committed to restoring nearly 1 billion hectares of degraded ecosystems.
A new report from UNEP and partners has found that global investment in nature needs to increase four-fold by 2050, equating to an annual investment of over USD 536 billion a year, to address the climate, biodiversity and land degradation crises. Countries have already committed to restoring nearly 1 billion hectares of degraded ecosystems. Currently, USD 130 billion per year flows into Nature-based Solutions, with public funds making up 86 per cent and private finance 14 per cent.
“New environmental measures and indicators are revealing with ever more precision not only what we are losing, but also what we will gain from bringing people and planet into balance,” said Tim Christophersen, Coordinator of the UN Decade on Ecosystem Restoration. “The case for investing in nature is only getting clearer.”
Nature for Human and Ecosystem Health is one of the key thematic areas of the resumed session of the UN Environment Assembly (UNEA5.2) to be held from 28 February to 2 March 2022. UNEA is the world’s highest environmental decision-making body. Through its resolutions and calls to action, the Assembly provides leadership and catalyzes intergovernmental action on the environment.
