Vegetation is an important component of the terrestrial ecosystem that plays an essential role in the exchange of water and energy in climate and biogeochemical cycles. This study investigated the spatiotemporal variation of normalized difference vegetation index (NDVI) in northern China using the GIMMS-MODIS NDVI during 1982–2018. We explored the dominant drivers of NDVI change using regression analyses. Results show that the regional average NDVI for northern China increased at a rate of 0.001 year⁻¹. NDVI improved and degraded area corresponded to 36.1% and 9.7% of the total investigated area, respectively. Climate drivers were responsible for NDVI change in 46.2% of the study area, and the regional average NDVI trend in the region where the dominant drivers were temperature (T), precipitation (P), and the combination of precipitation and temperature (P&T), increased at a rate of 0.0028, 0.0027, and 0.0056 year⁻¹, respectively. We conclude that P has positive dominant effects on NDVI in the subregion VIAiia, VIAiic, VIAiib, VIAib of temperate grassland region, and VIIBiia of temperate desert region in northern China. T has positive dominant effects on NDVI in the alpine vegetation region of Qinghai Tibet Plateau. NDVI is negatively dominated by T in the subregion VIIBiib, VIIBib, VIIAi, and VIIBi of temperate desert regions. Human activities affect NDVI directly by reforestation, especially in Shaanxi, Shanxi, and Hebei provinces.

Chinese torreya (Torreya grandis cv Merrilli) is a relict tree cultivar, distributed in the subtropical mixed broadleaved forest zone in eastern China. Chinese torreya was selected long time ago from quality trees of Torreya grandis Fort. ex Lind. and grafted on other Torreya trees, then cultivated by artificial propagation. Due to its commercial importance (e.g., nuts for food and medicinal uses), cultivation and development of large scale industrial plantations for Chinese torreya is under way. This review includes multiple perspectives on this cash tree cultivar, involving grafting, biological characteristics, distribution, functional food and health effects, as well as its contribution to local society, economy and environment. The advantage and challenge in cultivation, management and development of this cultivar in China are discussed. The information will be helpful for introducing this tree elsewhere, developing new products and exploring its livelihoods effects. It is proposed that sustainable development for organic food industry and medical use combined with ecotourism should be encouraged.

The longleaf pine (Pinus palustris Mill.) forests are important ecosystems in the southeastern USA because of their ecological and economic value. Since European settlement, longleaf pine ecosystems have dramatically declined in extent, to the degree that they are now listed as endangered ecosystems. Its sporadic seed production, which limits the frequency of natural regeneration, is identified as a significant factor in this decline. Previous studies did not characterize the complexity in cone production. Here a method of multiscale entropy is used to analyze long-term data for cone production in longleaf pine forests at six sites across its native range. Our results indicate that there exists a regime shift for cone production at each site. The corresponding time scales of the regime shift are generally 1–9, 10–12, 13–16, and 17–24 yr. Overall patterns for the complexity of cone production with the change of time scale are similar among sites, with exception of the Red Hills (FL). There are high correlations between entropy of cone production and entropy of annual mean air temperature and annual total precipitation at all sites. These results provide new insight into the complexity of cone production of longleaf pine forests with significant management implications.

Studying the capacity of some plant species to adapt to climate change is essential for ecological research and agricultural policy development. Chinese Torreya (Torreya grandis ‘Merrillii’) has been an important crop tree in subtropical China for over a thousand years. It is necessary to characterize its adaptation to climate change. In this study, the average monthly temperature and precipitation from 1901 to 2017 in the six regions with Chinese Torreya plantations at different provinces were analyzed. The results indicated that the average annual air temperature across these regions had increased by about 2.0 °C, but no general trend in the annual precipitation and incidence of drought was found. The annual air temperature that Chinese Torreya plantations had experienced was 12.96–18.23 °C; the highest and the lowest average monthly air temperatures were 30.1 °C and −0.8 °C, respectively. The lowest and the highest annual precipitation were 874.56 mm and 2501.88 mm, respectively. Chinese Torreya trees endured a severe drought period in the 1920s. The monthly air temperature at Zhuji, which is the central production region, showed a significant correlation with the air temperature in the other five regions. The monthly precipitation in Hunan and Guizhou had no significant correlation with that of Zhuji. Chinese Torreya plantations have been grown in the regions with a similar climate distance index of air temperatures but different precipitation. This tree has a high capacity to adapt to climate change based on the climate dynamics across its range. This approach may provide a way to evaluate climate adaptation in other tree species. These results may provide helpful information for the development of Chinese Torreya plantations.