BEIJING, Oct. 20 (Xinhua) -- For years, converting wetlands into farmland has been seen as a practical way to grow more food. However, a new global study shows that this strategy may not be as beneficial as once thought and could carry greater risks than expected.
Researchers led by the Institute of Geographic Sciences and Natural Resources Research (IGSNRR) of the Chinese Academy of Sciences, working with international partners, examined global croplands created from wetlands between 2000 and 2022. They assessed how much food these lands produced and their exposure to flooding. Their findings were recently published in the journal Nature Sustainability.
The findings show that wetland-reclaimed croplands contributed only marginally to global food production, accounting for just 0.1 percent of total crop output. In nearly half of these areas, yields were lower than on existing croplands, particularly for dryland crops. In 79 percent of the regions studied, their contribution to crop production was less than 1 percent.
These croplands also face significant flood exposure. Of these, 52 percent, covering about 21,000 square kilometers, are in areas prone to major flooding. On average, their flood exposure is 23 times that of croplands overall.
The study also found that 60 percent of wetland-reclaimed croplands combine limited agricultural benefits with high flood exposure. These areas are concentrated in East Asia, South Asia, North America, eastern South America and Oceania. They are especially common in food-importing or low-income countries.
According to Dong Jinwei, a researcher from IGSNRR, the study provides global evidence of the trade-offs between agricultural gains and ecological costs associated with wetland reclamation.
"Effective interventions are needed to ensure that agricultural expansion does not compromise critical wetland ecosystem services and long-term sustainability," Dong added. ■
