Abstract Agriculture contributes to deforestation and the conversion of other terrestrial ecosystems, affecting important ecosystem functions. A growing share of the produced agricultural commodities is traded between countries. It is widely assumed that international trade reduces humanity's pressure on land ecosystems by optimizing the mix of origin, i.e. by sourcing products from countries where land is used more efficiently. We examined if recent changes in the origin of agricultural products reduced humanity's impact on a fundamental ecosystem function, the net primary production (NPP) of vegetation. We performed an index decomposition analysis on a dataset of human appropriation of net primary production embodied in bilateral trade flows of 392 agricultural products between 167 countries (eHANPP) from 1986 to 2011. We found that while changes in the origin of agricultural products globally reduced HANPP in the 1990s, this trend reversed since 1999. This turn is explained by the increased sourcing of agricultural products from tropical regions, for exports and domestic consumption. After 2008, countries – on average – increasingly sourced their agricultural products from less efficient regions than in 1986. Our results suggest that the potential of trade to reduce humanity's impact on land ecosystems has not been exploited in the recent past.

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农产品贸易是否会减轻对土地生态系统的压力？分解人类对净初级生产的占有的驱动因素

摘要 农业导致森林砍伐和其他陆地生态系统的转化，影响重要的生态系统功能。越来越多的农产品在国家之间进行贸易。人们普遍认为，国际贸易通过优化原产地组合，即通过从土地使用效率更高的国家采购产品来减轻人类对土地生态系统的压力。我们研究了最近农产品来源的变化是否降低了人类对基本生态系统功能的影响，即植被的净初级生产 (NPP)。我们对 1986 年至 2011 年 167 个国家 (eHANPP) 之间 392 种农产品双边贸易流中包含的人类对净初级生产的占用数据集进行了指数分解分析。我们发现，虽然 1990 年代全球农产品来源的变化降低了 HANPP，但这种趋势自 1999 年以来发生了逆转。这一转变的原因是从热带地区采购的农产品增加，用于出口和国内消费。2008 年之后，与 1986 年相比，各国平均越来越多地从效率较低的地区采购农产品。我们的研究结果表明，贸易在减少人类对土地生态系统影响方面的潜力在近期并未得到开发。