• Energy Research

Abstract Despite the looming land scarcity for agriculture, cropland abandonment is widespread globally. Abandoned cropland can be reused to support food security and climate change mitigation. Here, we investigate the potentials and trade-offs of using global abandoned cropland for recultivation and restoring forests by natural regrowth, with spatially-explicit modelling and scenario analysis. We identify 101 Mha of abandoned cropland between 1992 and 2020, with a capability of concurrently delivering 29 to 363 Peta-calories yr− 1 of food production potential and 290 to 1,066 MtCO2 yr− 1 of net climate change mitigation potential, depending on land-use suitability and land allocation strategies. We also show that applying spatial prioritization is key to maximizing the achievable potentials of abandoned cropland and demonstrate other possible approaches to further increase these potentials. Our findings offer timely insights into the potentials of abandoned cropland and can inform sustainable land management to buttress food security and climate goals.

AbstractChina faces a complicated puzzle in balancing the country’s trade-offs among water and energy security, economic competitiveness, and environmental sustainability. It is therefore of prime importance to comprehend China’s water and energy security under the effect of its economic structural changes. Analyses of this issue still remain few and far between, and a comprehensive picture has not been available that would help understand the recent evolution of China’s economic structure as well as its spatial features and links to water and energy security, and policy-making. Consequently, we addressed these information gaps by performing an integrated and quantitative spatio-temporal analysis of the impacts of China’s industrial transition on water use intensity and energy-related carbon intensity. Those two factors are national indicators for policy-making targets of its water and energy security. Primary industry appeared to dominate the water use intensity although its relative share decreased, and the water use intensity of primary industry continued to be far higher than that of secondary and tertiary industries. In contrast, secondary industry dominated the total energy-related carbon intensity at both national and provincial scales. Besides, the total water use intensity and energy-related carbon intensity had a significant positive correlation.

Abstract China has been undergoing unprecedented urbanization since the 1978 economic reform, with the present growth rate of 20 million people per year. This rapid and perennial progress has been raising concerns about environmental sustainability, due to a severe nationwide deterioration of China's environment and ecosystems in the context of ceaselessly increasing demand for water and energy. It is therefore of prime necessity and importance to comprehend China's water and energy security under the effect of dramatic demographic changes. Analyses of this issue still remain few and far between, and a comprehensive picture is not available that would help understand China's recent development in urbanization, its spatial features and links to water and energy security, particularly regarding residential consumption, and related national policy-making. Consequently, we address these knowledge gaps by performing an integrated and quantitative spatio-temporal analysis of the impacts of China's urbanization on water use and energy-related CO2 emissions of residential consumption. We propose adding residential per capita water use and per capita energy-related CO2 emissions as national indicators for policy-making targets of China's water and energy security. Over the study period of 2003–2012, per capita rural residential water use was on the increase, while urban use showed the opposite trend. Rural consumption has been remarkably higher than the urban, and this gap appears to be growing. In contrast, the per capita energy-related CO2 emissions of residential consumption augmented significantly in both urban and rural areas nationwide. Besides, both the total and rural per capita residential water use and energy-related CO2 emissions showed a significant positive correlation. However, in urban areas this correlation was negative.