Brazil’s leadership in soybean and maize production depends on predictable rainfall in the Amazon-Cerrado agricultural frontier. Here we assess whether agricultural expansion and intensification in the region are approaching a climatic limit to rainfed production. We show that yields decline in years with unusually low rainfall or high aridity during the early stages of crop development—a pattern observed in rainfed and irrigated areas alike. Although agricultural expansion and intensification have increased over time, dry–hot weather during drought events has slowed their rate of growth. Recent regional warming and drying already have pushed 28% of current agricultural lands out of their optimum climate space. We project that 51% of the region’s agriculture will move out of that climate space by 2030 and 74% by 2060. Although agronomic adaptation strategies may relieve some of these impacts, maintaining native vegetation is a critical part of the solution for stabilizing the regional climate.
Efeito do substrato e de diferentes tratamentos pré-germinativos na germinação de sementes de Tento – Ormosia paraensis Ducke (Fabaceae)
Efeito do substrato e de diferentes tratamentos pré-germinativos na germinação de sementes de Tento – Ormosia paraensis Ducke (Fabaceae)
Este estudo objetivou avaliar a eficácia de tratamentos pré-germinativos em diferentes substratos para superar a dormência de sementes de Ormosia paraensis Ducke. Foram avaliados quatro tratamentos prégerminativos: 1) escarificação mecânica, 2) escarificação...