As one of the most important renewable and sustainable energy sources, the forest biomass energy resource has always been the focus of attention of scholars and policy makers. However, its potential is still uncertain in China, especially with respect to its spatial distribution. In this paper, the quantity and distribution of Chinese forest biomass energy resources are explored based mainly on forestry statistics data rather than forest resource inventory data used by most previous studies. The results show that the forest biomass energy resource in China was 169 million tons in 2010, of which wood felling and bucking residue (WFBR),wood processing residue (WPR), bamboo processing residue, fuel wood and firewood used by farmers accounted for 38%, 37%, 6%, 4% and 15%, respectively. The highest resource was located in East China, accounting for nearly 39.0% of the national amount, followed by the Southwest and South China regions, which accounted for 17.4% and 16.3%, respectively. At the provincial scale, Shandong has the highest distribution, accounting for 11.9% of total resources, followed by Guangxi and Fujian accounting for 10.3% and 10.2%, respectively. The actual wood-processing residue (AWPR) estimated from the actual production of different wood products (considering the wood transferred between regions) showed apparent differences from the local wood processing residue (LWPR), which assumes that no wood has been transferredbetween regions. Due to the large contribution of WPR to total forestry bioenergy resources, the estimation of AWPR will provide a more accurate evaluation of the total amount and the spatial distribution of forest biomass energy resources in China.

Cotton seed production is the main form of agriculture in Xinjiang, China. Unreasonable distribution of cotton seed production results in a waste of water, land, and human resources. In this study, we established a hierarchical classification integrating method; investigated the spatial suitability of climate, land and water resources, and infrastructure; examined the production risk and planting history; and integrated spatial suitability and production risk and history to produce the spatial layout of seed production for early-maturing cotton (EMC), early–medium-maturing cotton (EMMC), and long staple cotton (LSC) in Xinjiang. The results indicated that the appropriate areas for EMC, EMMC, and LSC seed production are 6.4 × 10⁵, 5.5 × 10⁵, and 3.6 × 10⁵ ha, respectively. By combining the suitable areas of seed production for the three cotton species, we concluded that the superior and most suitable area for producing cotton seed of EMC, EMMC, or LSC is located in the western Tarim Basin. The sub-suitable area for cotton seed production of EMC, EMMC, or LSC is mostly distributed in the western and northern Tarim Basin. This research provides a good solution to the selection of cotton seed production base; however, adoption will depend on the actual preference and market factors.

Afforestation in the Three North Region (TNR) of China has received wide concern due to the low survival rate and threats to water security associated with the lack of available precipitation for vegetation. It is crucial to provide a spatial layout for revegetation according to the available precipitation to achieve the vegetation cover target. This study investigated the spatial pattern of precipitation, determined the suitable vegetation distribution based on the ecological water requirements and precipitation, and proposed an optimized revegetation scheme by comparing the actual and suitable vegetation patterns. The results indicated that the actual vegetation that matched the pixel-level precipitation accounted for 67.24% of the total vegetation area in the TNR. However, 18.50% of the actual forest, 21.82% of the actual shrublands, and 19.95% of the actual grasslands were overloaded with respect to precipitation. The total suitable vegetation area was reduced slightly compared to the actual vegetation area. There is still some potential for the revegetation of forest and shrublands, mainly those in the eastern and south-eastern parts of the TNR. The optimized revegetation area in the TNR was 3.04 × 10⁶ km², including a maintenance management type of 2.19 × 10⁶ km², an upgrade type of 0.49 × 10⁶ km², and a degradation type of 0.37 × 10⁶ km². Maintenance management (natural restoration) and transformation to vegetation types with lower ecological water requirements were recognized as important revegetation practices in the TNR. This study provides guidelines to adjust the Three North Shelterbelt Project policies based on precipitation data to reduce the negative impact of revegetation on the hydrological cycle.

The quantity and quality of cropland plays an important role in ensuring food security. In order to explore spatiotemporal patterns of the extent to which cropland satisfies people’s grain need, we integrate multi-source heterogeneous data to investigate in which era, and in which region, the cultivated land can meet people’s food demands. It turns out that in the past 30 years, with the exception of the late 1980s, the amount of cropland could satisfy people’s grain needs at the nation scale. However, more than 10 provinces (municipality/autonomous region), mainly located in western China and southeast coastal areas, have been unable to meet the grain needs of local people. We projected the guarantee rate to the late 2020s. Our study concludes that the guarantee rate of cropland is estimated to be higher than 150% in China. Compared to 2019, except Beijing, Tianjin, Liaoning, Jilin, Ningxia, as well as Heilongjiang in the Sustainability scenario, and Shanghai in the Sustainability and the Equality scenarios, the guarantee rate of cultivated land will increase in every province (municipality/autonomous region) in 2030. This study has reference value for the study of China’s cultivated land protection system, as well as important significance for China’s sustainable development.