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• This paper performs the first meta -regression analysis of Chinese aid effectiveness using 1,149 estimates from 29 studies. • Chinese aid is positively associated with economic outcomes in recipient countries. • Chinese aid correlates with deforestation and negative perceptions of China among citizens, albeit negligible in size. • Sub-sample MRAs detect publication selection bias in the Chinese aid effectiveness literature. • Heterogeneity is driven by differences in the choice of data, estimation method, and authors' institutional affiliation. This paper employs a meta -regression analysis of 1,149 estimates from 29 studies to take stock of the empirical literature on Chinese aid effectiveness. After accommodating publication selection bias, we find that, on average, Beijing's foreign assistance is positively associated with economic outcomes in recipient countries, but correlates with deforestation and negative perceptions of China among citizens, albeit negligible in size. We also show that studies that fail to uncover empirical effects that conform to researchers' expectations are less likely to be submitted or accepted for publication. Differences in the choice of data, estimation method, and authors' institutional affiliation explain the heterogeneity among Chinese aid effectiveness estimates reported in the literature. [ABSTRACT FROM AUTHOR]

The world's forests have historically been managed as systems in which environmental health is compromised for the sake of economic efficiency and growth. China's forest policy framework has generally followed this paradigm as large-scale deforestation over the 20th century led to landscapes that, while economically productive, were made vulnerable to natural disturbances. However, in recent decades China has experienced substantial forest reforms that aim to protect important forested lands while simultaneously increasing timber outputs from plantations. Multiple green growth oriented programs have been in place to attain these objectives with the anticipation that rural poverty can be alleviated and the vulnerability towards natural disasters can be avoided. A growing body of research demonstrates the success of these reforms for improving the lives of landowners while also increasing the country's forest cover. However, these reforms have brought upon substantial change to the relationship within and between social, economic and ecological properties of the nation's forest system, and consequentially its ability to respond and adapt to change in the future. The objective of this paper is to describe the relationship between forest policy and environmental change in China during the last century using a complex adaptive systems framework. This approach demonstrates the coupled nature of policies and forest dynamics that need to be considered in future policy development. China's green growth directed policies and practices must embrace a perspective of constant change and the inevitability of perturbations and disturbances. In this way, China can begin to consider how to build resilience into its policies and management strategies so that the overall system maintains a level of flexibility that allows it to adapt to unforeseen economic and ecological change. [ABSTRACT FROM AUTHOR]

The end-Triassic mass extinction (ETE), one of the five largest mass extinctions, occurred at 201.6 Ma. It was characterized by dramatic declines in marine and terrestrial ecosystems and was approximately synchronous with the eruption of the Central Atlantic Magmatic Province (CAMP). Loss of marine biodiversity is linked to extreme global warming while the cause of floral destruction in terrestrial ecosystems remains open to debate. In this paper, biomarker records of higher plants are reported from terrestrial facies in the Haojiagou section of the high palaeolatitude Junggar Basin, northwest China. Strata around the ETE interval are marked by sharp increases in the abundances of cadalene, retene, pimanthrene and furans, which are synchronous with "fern spikes". These results are interpreted as indicating the demise of land vegetation and the enhanced burial of higher plants, consistent with palynological evidence for the loss of floral diversity. The fluctuations in the abundance of n -alkanes series and conversion of n -alkanes peak patterns coincide with wildfires indicated by polycyclic aromatic hydrocarbons. Based on integrated stratigraphic correlation, the increased burial of higher plants, wildfires and CAMP volcanism are synchronous both in the Haojiagou section and other classic Triassic-Jurassic boundary sections globally. We propose that widespread deforestation may be due to CAMP-derived acid rain and the rapid and large-scale demise of vegetation may have provided moisture-free fuels for wildfires. • Higher plant biomarkers are first reported in a high palaeolatitude terrestrial basin across the Triassic-Jurassic transition. • Similar biomarker features are witnessed at worldwide marine and terrestrial sections, suggesting a global deforestation. • Extensive deforestation and wildfires during the ETE period could be initially caused by the CAMP-originated acid rainfalls. [ABSTRACT FROM AUTHOR]

• We propose a new forest prediction model and use actual deforestation data for optimization and verification. • Use the XGBoost method to reconstruct deforestation intensity data. • Deforestation hotspots in China are mainly concentrated in the southern and southeastern regions. • Our model provides certain reference information for forest disaster prevention and forest management. Forests are important for the global carbon cycle, hydrothermal balance, and climate change. Human activities can exert a significant impact on forest ecosystems, thereby having the potential to alter their physical and chemical properties and thus affecting carbon, water, and heat budgets, and climate change. The historical reconstruction of the disturbance of global forests can help us understand the processes and patterns of human activities and global change. In this paper, we construct a deforestation prediction model using a Spearman correlation coefficient and implement the XGBoost method, using Python 3.6, for the reconstruction of deforestation intensity data from 2000 to 2019. Secondly, the selection of the driver indicators is done by using extreme difference regularization to unify the magnitude, and the potential deforestation area risk index is calculated in the form of equal weights. Finally, the actual deforestation data were used for optimization and validation. The model shows that the deforestation hotspots are mainly concentrated in the southern and southeastern regions of China and that there are large differences in deforestation in different provinces. In the future, the fine spatial and temporal patterns of deforestation in China during the historical period can be quantitatively reconstructed, which can provide some reference information for forest disaster prevention and forest management in China. [ABSTRACT FROM AUTHOR]

Abstract: Long-term deforestation and over-harvesting directly led to serious soil erosion and sharp forest deterioration, and the Eco-Environment in Mudanjiang became worse and worse. So the government there took the Returning Farmland to Forest Project (RFFP) firstly in Heilongjiang Province in China in 1999. On the basis of deeply understanding the Eco-Environmental problem of soil erosion and the Ecological Risk Definition, this paper put forward an Ecological Risk Assessment Model with Landscape Indexes and Eco-Environment Resilience. This model firstly calculated the landscape indexes of every sample by fragstats and then obtained the spatial distribution of Ecological Risk by ordinary Kruger interpolation. The results showed that: the landscape fragmentation improved after the RFFP, the Eco-Environment Resilience increased significantly because the forest area increased obviously and the serious soil erosion was controlled by the high vegetation cover, which in the end made the Ecological Risk drop down rapidly, from 0.003-0.952 to 0.003-0.310. The area proportion of minor, slight and moderate risk increased separately from 7.65%, 13.71% and 21.39% to 18.85%, 33.04% and 33.24%, while the intense and server declined respectively from 31.46% and 25.79% to 14.88% and 0%. In a word, the model possessed advantages of intuition and simplicity and could descript the regional ecological risk quantitatively and its spatial distribution intuitively. [Copyright &y& Elsevier]

Abstract: China has a long history of large-scale deforestation that has contributed to serious consequences such as frequent geological disaster, flood and soil erosion. It was only recently that forest management strategy shifted from the traditional harvesting orientation to a more balanced forest ecosystem management approach with a focus on conservation. To understand the effects of such a shift, on the forest dynamics especially since the implementation of Natural Forest protection Project (NFPP), this paper examined the case of Lushuihe region, a typical region of the northeast China forest zone. Land use and landscape pattern for the period of 1975–2007 were analyzed based on Landsat MSS and TM images. Net primary, productivity (NPP), estimated with the CASA productivity model, was used to assess the human impacts on the forest ecosystem function. The results showed a reversing trend of forest cover since 1988, from continuous decrease to rather rapid increase. From 1975 to 1988, due to reckless deforestation, the forest cover in the case region decreased about 10439.39ha (8.54% of the study area). Forest cover of the region recovered from 77.68% in 1988 to 89.56% in 1999 and 92.33% in 2007. While the forest cover increased, landscape metrics indicate that human disturbance significantly altered the composition and structure of the forest landscape. NPP change indicated a continued decreasing trend until 2007, albeit at a slower pace since 1988. In 2007, while the decreasing trend of NPP was reversed, the forest structure was still inferior to that of 1975. Looking forward, diversifying and securing the livelihoods of the still growing local population that have been heavily dependent on the traditional forestry industry remain one of the key challenges as well as solutions for enhancing and managing the regional forest ecosystem structure and function in the region. [Copyright &y& Elsevier]

Abstract: This paper examines the spatial variation of sediment yield in the Yangtze basin in China, a large basin with complex geology, climate, land-use history, and extensive sediment monitoring. 287 stations with drainage area less than 10,000km2 were used to study the scale effects of sediment yield. In order to develop scale relations for regional sediment yield, the whole study area was divided into eight sub-basins. Relation between specific sediment yield and drainage basin area was built for each sub-basin. Regional scaling relation was analyzed based on landforms, geology, lithology and land-use of each sub-basin. Three regional trends were identified in relation to the drainage area: (1) a declining trend, due to soil erosion on heavily cultivated steep land and the storage of sediment in floodplains; (2) a flat trend, due to mass movement on the upper reach and heavy agricultural disturbance on the middle and lower reaches; and (3) an increasing trend, due to downstream recruitment of sediment from land downstream where slope farming and deforestation occurred. Using these developed relations, areally adjusted sediment yield maps were created over the entire Yangtze basin. [Copyright &y& Elsevier]

Abstract: Soil degradation caused by deforestation is one of main environmental problems all over the world. The objective of this paper was to quantitatively evaluate the effects of erosion patterns on organic matter, nitrogen and phosphorus (P) losses, by monitoring soil erosion and nutrient loss in newly deforested lands in the Ziwuling region on the Loess Plateau of China from 1986 to 1996. Eight field runoff plots, with various sizes to enable documentation different combinations of dominant erosion processes, were established on a hillslope. Results showed that the nutrient loss was dramatically affected by erosion patterns and erosion intensity. Seven years after deforestation, organic matter, total nitrogen, ammonium nitrogen and available P reduced by 69, 46.7, 65.6 and 86.6%, respectively. The most severe soil erosion and nutrient loss occurred in the ephemeral gully channels. Organic matter, total nitrogen, ammonium nitrogen and available P had different nutrient enrichment ratios in eroded sediment. The available P had the highest enrichment ratios, followed by ammonium nitrogen. The nutrient enrichment ratios were closely related to sediment concentration and erosion patterns. In sheet erosion zone, the nutrient enrichment ratios in eroded sediment decreased with an increase of sediment concentration; in the combined erosion zones of sheet, rill and shallow gully, the nutrient enrichment ratios in sediment initially decreased and then increased with an increase of sediment concentration. The nutrient enrichment in eroded sediment also greatly affects by rainfall characteristics such as rainfall amount and intensity. [Copyright &y& Elsevier]