Dataset Information

China's fight to halt tree cover loss.

ABSTRACT: China is investing immense resources for planting trees, totalling more than US$ 100 billion in the past decade alone. Every year, China reports more afforestation than the rest of the world combined. Here, we show that China's forest cover gains are highly definition-dependent. If the definition of 'forest' follows FAO criteria (including immature and temporarily unstocked areas), China has gained 434 000 km2 between 2000 and 2010. However, remotely detectable gains of vegetation that non-specialists would view as forest (tree cover higher than 5 m and minimum 50% crown cover) are an order of magnitude less (33 000 km2). Using high-resolution maps and environmental modelling, we estimate that approximately 50% of the world's forest with minimum 50% crown cover has been lost in the past approximately 10 000 years. China historically lost 1.9-2.7 million km2 (59-67%), and substantial losses continue. At the same time, most of China's afforestation investment targets environments that our model classes as unsuitable for trees. Here, gains detectable via satellite imagery are limited. Conversely, the regions where modest gains are detected are environmentally suitable but have received little afforestation investment due to conflicting land-use demands for agriculture and urbanization. This highlights the need for refined forest monitoring, and greater consideration of environmental suitability in afforestation programmes.

SUBMITTER: Ahrends A

PROVIDER: S-EPMC5443932 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

China's fight to halt tree cover loss.

Ahrends Antje A Hollingsworth Peter M PM Beckschäfer Philip P Chen Huafang H Zomer Robert J RJ Zhang Lubiao L Wang Mingcheng M Xu Jianchu J

Proceedings. Biological sciences 20170501 1854

China is investing immense resources for planting trees, totalling more than US$ 100 billion in the past decade alone. Every year, China reports more afforestation than the rest of the world combined. Here, we show that China's forest cover gains are highly definition-dependent. If the definition of 'forest' follows FAO criteria (including immature and temporarily unstocked areas), China has gained 434 000 km<sup>2</sup> between 2000 and 2010. However, remotely detectable gains of vegetation tha ...[more]

PMID: 28469024

Similar Datasets

Project description:BackgroundSunburn is the strongest risk factor for melanoma and non-melanoma skin cancers. Adolescent sunburns are related to higher risk of developing melanoma later in life. Little is known about the association of sunburns and shade, particularly tree cover, around adolescent homes and schools. This linkage study assessed associations of adolescent self-reported sunburns with ambient ultraviolet radiation (UV) and tree cover.MethodsWe analyzed a U.S. national sample of parent-child dyads (n?=?1333) from the 2014 Family Life, Activity, Sun, Health, and Eating (FLASHE) study conducted by the National Cancer Institute. The outcome was adolescent sunburns reported for the previous 12 months. GIS buffers around geocoded home and school addresses were used to summarize UV and tree cover. A sensitivity analysis assessed different UV measures and tree cover buffer distances. Logistic regression models estimated the adjusted odds of any sunburns for five models: (1) no environmental variables; (2) spatial variables of latitude and longitude; (3) UV; (4) tree cover; and, (5) a combined model with UV and tree cover. Covariates included common sunburn-related items such as sun protective behaviors, socio-demographics, and latitude. Model residuals were assessed for spatial dependency and clustering.ResultsOverall, 44% of adolescents reported any sunburns in the previous 12 months. For the bivariate associations, lower categories of UV were associated with any reported sunburns (p-trend?=?0.002). Home tree cover was not associated with any reported sunburns (p-trend?=?0.08), whereas schools with lower categories of tree cover were associated with sunburns (p-trend?=?0.008). The adjusted odds of any sunburns by UV tertiles, as a linear tread, was 0.89 (0.76-1.05) (p?=?0.17); school tree cover was: 0.91 (0.78-1.07) (p?=?0.25). Neither UV nor tree cover, in a combined model, were significant. Sensitivity analyses resulted in the optimal buffer size of 200 m for summarizing tree cover. Spatial dependence of residuals was not significant and clustering was significant for about 6% or less of the sample in each model.ConclusionsWe did not find significant relationships between UV or tree cover and adolescent sunburns, when adjusted by sunburn-related covariates. Better contextual data about where sunburns occurred is needed to identify environmental correlates of sunburn.

Project description:Osteoporosis (OP) is a systemic skeletal disorder, manifesting with a reduction in bone mass and deterioration of the microarchitecture. Mesenchymal stem cells (MSCs) have an innate ability to differentiate into several cell types, including osteoblasts (OB). Ginsenoside Rb1 (GRb1) is an ethanol extract from ginseng and contains a highly concentrated form of ginsenoside. GRb1 shows extensive beneficial health effects such as anti-oxidative and anti-inflammatory functions, modulating the immune system and inhibiting osteoclastogenesis. We hypothesized that GRb1 can promote MSC differentiation into OBs and inhibit bone loss. In the present study, we aimed to address two questions: (1) Will GRb1 have a positive effect on osteogenic differentiation of MSCs? and (2) Will GRb1 halt bone loss in ovariectomized (OVX) rats? We investigated the effects of GRb1 on viability and osteogenic differentiation of rat mesenchymal stem cells (rMSCs). Our results showed that GRb1 at concentrations of 10-8 M and 10-6 M can increase alkaline phosphatase activity, mineralization and the expression of osteogenic related proteins, such as osteopontin and osteoprotegerin, while incubating rMSCs with osteogenic induction medium and GRb1. Adding GRb1 into the medium can prevent rMSCs from Oxidative damage at the concentration of 25?M H2O2. Furthermore, 40 4-month-old rats were assigned to 5 groups(8 rats per group): the basal group, the sham group, the OVX group, the high dose of GRb1 group (6 mg/kg/day) and the low dose of GRb1 group (3 mg/kg/day). Rats recrived treatment 3days after surgery and last for 14 weeks. Examinations included serum analysis, mechanical testing, Masson-Goldner trichrome staining and bone histomorphometry analysis. The results showed that OVX can lead to dyslipidemia and excessive oxidative stress, whereas GRb1 cannot significantly halt dyslipidemia and excessive oxidative stress in OVX rats. In addition, the bone density of the lumbar vertebra and femur were decreased significantly in the OVX rats, and GRb1 could not inhibit bone loss. Bone histomorphometry analysis showed that the number and width of bone trabecula of the tibia were reduced in OVX rats, and GRb1 could not prevent their occurrence. A bone biomechanics assay showed that GRb1 cannot improve the ability of bone structure to resist fracture of the femur in OVX rats. The current study demonstrated that GRb1 has an obvious effect on osteogenic differentiation in rMSCs but no obvious effect on bone loss in OVX rats. These findings indicate GRb1 has a positive effect on rMSCs but does not have an effect on bone loss in OVX rats at the concentration we used.

Dataset Information

China's fight to halt tree cover loss.

Publications

China's fight to halt tree cover loss.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets