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1.
Nat Ecol Evol ; 8(2): 251-266, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182682

RESUMO

The biodiversity impacts of agricultural deforestation vary widely across regions. Previous efforts to explain this variation have focused exclusively on the landscape features and management regimes of agricultural systems, neglecting the potentially critical role of ecological filtering in shaping deforestation tolerance of extant species assemblages at large geographical scales via selection for functional traits. Here we provide a large-scale test of this role using a global database of species abundance ratios between matched agricultural and native forest sites that comprises 71 avian assemblages reported in 44 primary studies, and a companion database of 10 functional traits for all 2,647 species involved. Using meta-analytic, phylogenetic and multivariate methods, we show that beyond agricultural features, filtering by the extent of natural environmental variability and the severity of historical anthropogenic deforestation shapes the varying deforestation impacts across species assemblages. For assemblages under greater environmental variability-proxied by drier and more seasonal climates under a greater disturbance regime-and longer deforestation histories, filtering has attenuated the negative impacts of current deforestation by selecting for functional traits linked to stronger deforestation tolerance. Our study provides a previously largely missing piece of knowledge in understanding and managing the biodiversity consequences of deforestation by agricultural deforestation.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Filogenia , Florestas , Agricultura
2.
J Environ Manage ; 330: 117190, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603263

RESUMO

An ambitious new Post-2020 Global Biodiversity Framework "Kunming-Montreal Global Biodiversity Framework" has been developed. However, the combined effects of climate change and human modification can undermine the potential benefits of the global post-2020 conservation efforts. The co-benefits of stabilizing the climate, conserving biodiversity, and maintaining intact wilderness areas may help to persuade the general public of the need to quickly expand existing protected areas (PAs). To maximize the co-benefits after 2020, the careful optimization of existing (PAs) network and scientific identification of conservation targets are both essential. Here, we mapped hotspots of biodiversity, climate vulnerability, and wilderness in Southwest China (SWC). By analyzing the representativeness and gaps of the existing PAs network in SWC, we devised post-2020 conservation targets and highlighted their implications for decision-makers. Our results showed that the incongruence between hotspots of different species exists, indicating that habitats suitable for one taxon may not fully harbor other taxa. According to our assessment, the five jurisdictions of SWC have warmed on average by 0.4°C-1.1 °C over the past 60 years alone. In particular, biodiversity hotspots in SWC are undergoing stark climatic changes. We uncovered prominent conservation gaps in SWC's network of PAs, especially in terms of climate vulnerability and biodiversity. Due to their insufficient number and unreasonable spatial distribution, the PAs network in SWC may be not capable of meeting its biodiversity, climate vulnerability, and wilderness conservation objectives. To rectify this, we proposed a 3-step mission: milestone 2025, milestone 2030, and goal 2050, which aims to protect 23%, 28%, and 60% of the terrestrial area in SWC, respectively. Taken together, our study derived conservation priority areas with relatively clear spatial boundaries and importance levels, thus providing detailed, timely information for decision-makers to expand the PAs network and implement conservation measures varying in strictness in post-2020 conservation practice.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Biodiversidade , China , Conservação dos Recursos Naturais/métodos , Ecossistema
3.
J Environ Manage ; 325(Pt A): 116505, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36270131

RESUMO

As the most biodiversity-rich part of the protected areas system, habitats within the pilot national parks have long been threatened by drastic human-induced land use and land cover changes. The growing concern about habitat loss has spurred China's national park project to shift from pilot to construction phase with the official establishment of China's first group of national parks (CFGNPs) in October 2021. But far too little attention has been paid to the synergistic work concerning the habitat quality (HQ) dynamics of all five national parks. Here, the InVEST model, combined with a satellite-derived land use and land cover product and a hot spot analysis (HSA) method, was used to investigate the HQ dynamics at the park- and pixel-scale within the CFGNPs. Our results demonstrate that the past ecological conservation practices within national parks have been unpromising, especially in Giant Panda National Park, Northeast China Tiger and Leopard National Park (NCTL), and Wuyi Mountain National Park (WYM), where HQ as a whole showed a significant decline. Furthermore, more than half of Hainan Tropical Rainforest National Park (87.2%), WYM (77.4%), and NCTL (52.9%) showed significant HQ degradation from 1980 to 2019. Besides, increasing trends in the area shares of HQ degraded pixels were observed in all five national parks from 1980-1999 to 2000-2019. The HSA implied that the hot spots of high HQ degradation rates tend to occur in areas closer to urban settlements or on the edge of national parks, where human activities are intensive. Despite these disappointing findings, we highlighted from the observed local successes and the HQ plateau that the construction of CFGNPs is expected to reverse the deteriorating HQ trends. Thus, we concluded our paper by proposing an HSA-based regulatory zoning scheme that includes five subzones to guide the future construction of China's national park system.


Assuntos
Conservação dos Recursos Naturais , Parques Recreativos , Humanos , Conservação dos Recursos Naturais/métodos , Ecossistema , Biodiversidade , China
4.
iScience ; 25(12): 105660, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36567714

RESUMO

Various global land use/land cover (LULC) products have been developed to drive land-relevant climate and hydrological models for environmental assessments. However, systematic studies remain scarce that assess the uncertainties of using these products. By using a total of 16 commonly used global LULC products, we find a logarithm law of upscaling with the spatial resolution. The law reveals spatial details of urban features will be majorly distorted when using LULC products with coarser resolutions. A tipping point of the law around the 30-m resolution was identified by additional analysis of the 1-m and 10-m local land use dataset. Through the example of assessing crop production loss, we further find that most of these products will yield a significant underestimation of crop production losses, globally and locally. We conclude that the underestimated urban land rooted in most of these products would cause vital impacts on global change analyses and modeling.

5.
Sci Data ; 9(1): 141, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365677

RESUMO

Plantation is an important land use type that differs from natural forests and affects the economy and the environment. Tree age is one of the key factors used to quantify the impact of plantations. However, there is a lack of datasets explicitly documenting the planting years of global plantations. Here we used time-series Landsat archive from 1982 to 2020 and the LandTrendr algorithm to generate global maps of planting years based on the global plantation extent products in Google Earth Engine (GEE) platform. The datasets developed in this study are in a GeoTIFF format with 30-meter spatial resolution by recording gridded specie types and planting years of global plantations. The derived dataset could be used for yield prediction of tree crops and social and ecological cost-benefit analysis of plantations.

6.
Sci Total Environ ; 825: 153938, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35183635

RESUMO

China is prone to broad land degradation and thus has been implementing ecological restoration projects (ERPs) since the reform and opening up. The extent of ERPs, as well as the varied planting efforts including tree gain projects (TGPs), grass gain projects (GGPs), and shrub gain projects (SGPs), have remained largely unknown. In addition, the mixed success of ERPs on preventing soil erosion and improving biodiversity is not well known. Based on a land use and land cover (LULC) product and a trajectory-based change detection approach, we successfully generated the first national map of ERPs associated with land use and land cover change (LUCC) and its three associated subcategories. Then, we applied the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model to evaluate the dynamics of sediment retention and habitat quality. In addition, we explored the heterogeneous patterns for the ecological impacts of ERPs. Our results suggested that during the past 40 years, a total ERP area of 9.54 × 106 hm2 was observed nationwide, mainly in the northwestern provinces of China. Of the three ERP subcategories, TGPs accounted for the largest area (48.55%), followed by GGPs (47.50%) and SGPs (3.96%). The national average sediment retention experienced a significant increase, whereas the national average habitat quality experienced a significant decline. ERP-driven increases in habitat quality were offset partly by the LUCCs induced by economic development policies in some regions, especially in northeast China. The simultaneous effect of construction land expansion and ERP implementation on sediment retention made the synchronization between ERP implementation and sediment retention improvement insignificant. We also suggested the optimal direction for ERP implementation.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , China
7.
Trials ; 21(1): 261, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164719

RESUMO

BACKGROUND: Insomnia is a global disease with a high incidence and acupuncture therapy is a well appropriate method to treat insomnia. Shenmen (HT 7) and Sanyinjiao (SP 6) are the acupoints most commonly used to treat insomnia. Although they can obviously relieve the clinical symptoms of insomnia, it is unclear whether they must be used together, whether the combination of two acupoints may have a synergistic or antagonistic effect, and whether there is a primary or secondary relationship between the two points in the treatment of insomnia. Further studies are needed. Therefore, in this study, we are exploring the acupoint combination effect and biological mechanism of HT 7 and SP 6 in treating insomnia. METHODS/DESIGN: This will be a parallel group randomized controlled trial. The study will recruit 120 patients with insomnia randomly assigned to a control group, an electroacupuncture on HT 7 group, an electroacupuncture on SP 6 group, and an electroacupuncture on HT 7 and SP 6 group. The allocation ratio is 1:1:1:1, with 30 subjects in each group. Meanwhile, ten healthy subjects who meet the study criteria will be recruited as the healthy control group. Patients in the intervention groups will be given ten rounds of electroacupuncture stimulation on the corresponding acupoints for 2 weeks, five times per week, with 2 days of rest between the two treatment courses. Patients in the control group will also receive the same two courses of ten rounds of compensatory acupuncture therapy after a 2-week waiting period for treatment. The major outcome measures of this study include the Sleep Dysfunction Rating Scale, the Insomnia Severity Index, Epworth Sleepiness Scale, the Zung Self-Rating Anxiety Scale, and the Zung Self-Rating Depression Scale, combined with the Measure Your Medical Outcome Profile, to evaluate insomnia and the emotional state of patients with insomnia. The secondary outcome measures include sleep composition monitored by polysomnography and measurements of acetylcholine, serotonin, dopamine, norepinephrine, melatonin, gamma-aminobutyric acid, and metabolic biomarkers in serum. DISCUSSION: In this study, we are exploring the acupoint combination effect and biological mechanism of HT 7 and SP 6 in treating insomnia, which may provide evidence for the clinical application of acupuncture and acupoint selection in the treatment of insomnia. TRIAL REGISTRATION: Chinese Clinical Trial Registry, Chi-CTR-1800017483. Registered on 1 August 2018.


Assuntos
Pontos de Acupuntura , Biomarcadores/sangue , Eletroacupuntura , Distúrbios do Início e da Manutenção do Sono/terapia , Acetilcolina/sangue , Dopamina/sangue , Humanos , Melatonina/sangue , Estudos Multicêntricos como Assunto , Polissonografia , Ensaios Clínicos Controlados Aleatórios como Assunto , Distúrbios do Início e da Manutenção do Sono/sangue , Resultado do Tratamento
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