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Summary Tropical deforestation has caused a significant share of carbon emissions and species losses, but historical patterns have rarely been explicitly considered when estimating these impacts [ 1 ]. A deforestation event today leads to a time-delayed future release of carbon, from the eventual decay either of forest products or of slash left at the site [ 2 ]. Similarly, deforestation often does not result in the immediate loss of species, and communities may exhibit a process of “relaxation” to their new equilibrium over time [ 3 ]. We used a spatially explicit land cover change model [ 4 ] to reconstruct the annual rates and spatial patterns of tropical deforestation that occurred between 1950 and 2009 in the Amazon, in the Congo Basin, and across Southeast Asia. Using these patterns, we estimated the resulting gross vegetation carbon emissions [ 2, 5 ] and species losses over time [ 6 ]. Importantly, we accounted for the time lags inherent in both the release of carbon and the extinction of species. We show that even if deforestation had completely halted in 2010, time lags ensured there would still be a carbon emissions debt of at least 8.6 petagrams, equivalent to 5–10 years of global deforestation, and an extinction debt of more than 140 bird, mammal, and amphibian forest-specific species, which if paid, would increase the number of 20 th -century extinctions in these groups by 120%. Given the magnitude of these debts, commitments to reduce emissions and biodiversity loss are unlikely to be realized without specific actions that directly address this damaging environmental legacy. [ABSTRACT FROM AUTHOR]

The co-evolution of multi-cities has emerged as the primary form of urbanization in China in recent years. However, the processes, patterns, and coordination are not well characterized and understood, which hinders the understanding of the driving forces, consequences, and management of polycentric urban development. We used the Continuous Change Detection and Classification (CCDC) algorithm to integrate all available Landsat 5, 7, and 8 images and map annual land use and land cover (LULC) from 2001 to 2017 in the Chang–Zhu–Tan urban agglomeration (CZTUA), a typical urban agglomeration in China. Results showed that the impervious surface in the study area expanded by 371 km2 with an annual growth rate of 2.25%, primarily at the cost of cropland (169 km2) and forest (206 km2) during the study period. Urban growth has evolved from infilling being the dominant type in the earlier period to mainly edge-expansion and leapfrogging in the core cities, and from no dominant type to mainly leapfrogging in the satellite cities. The unfolding of the "cool center and hot edge" urban growth pattern in CZTUA, characterized by higher expansion rates in the peripheral than in the core cities, may signify a new form of the co-evolution of multi-cities in the process of urbanization. Detailed urban management and planning policies in CZTUA were analyzed. The co-evolution of multi-cities principles need to be studied in more extensive regions, which could help policymakers to promote sustainable and livable development in the future. [ABSTRACT FROM AUTHOR]

Understanding the effects of forest management strategies is especially important to avoid unregulated natural resource extraction that leads to ecosystem degradation. In addition to the loss of crucial forest services, inefficiencies at converting these natural resources into economic gain for people ultimately exacerbates poverty. Therefore, it is important to know which conservation strategies have proven to be effective in preventing ecosystem degradation and thus be encouraged in future management plans. Here, we used a high-resolution remotely sensed dataset spanning 15 years to study forest cover dynamics across various protected areas in Tanzania. Our findings highlight particular management approaches more effective in preventing forest cover loss and promote forest cover gain, and provide valuable information for conservation efforts. Results show that National Parks have the least forest cover loss, whereas multiple-use Game Controlled Areas have the highest rates of forest loss. In fact, results suggest that these multiple use areas tend to lose more forest cover than areas with no protection or management status at all. These findings suggest the need for more effective strategies for enforcing the existing policies to ensure that socio-economic benefits to local communities are maximized and national interests are sustained. [ABSTRACT FROM AUTHOR]