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1.
Sci Total Environ ; 932: 173034, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38719061

RESUMO

Vegetation redistribution may bring unexpected climate-soil carbon cycling in terrestrial biomes. However, whether and how vegetation redistribution alters the soil carbon pool under climate change is still poorly understood on the Tibetan Plateau. Here, we applied the G-Range model to simulate the cover of herbs, shrubs and trees, net primary productivity (NPP) and soil organic carbon density (SOCD) at the depth of 60 cm on Tibetan Plateau for the individual years 2020 and 2060, using climate projection for Representative Concentration Pathways (RCP) 4.5 and RCP8.5 scenarios with the RegCM4.6 model system. Vegetation redistribution was defined as the transitions in bare ground, herbs, shrubs and trees between 2020 and 2060, with approximately 57.9 % (RCP4.5) and 59 % (RCP8.5) of the area will redistribute vegetation over the whole Tibetan Plateau. The vegetation cover will increase by about 2.4 % (RCP4.5) and 1.9 % (RCP8.5), while the NPP and SOCD will decrease by about -14.3 g C m-2 yr-1 and -907 g C m-2 (RCP4.5), and -1.8 g C m-2 yr-1and -920 g C m-2 (RCP8.5). Shrubs and trees will expand in the east, and herbs will expand in the northwest part of the Plateau. These areas are projected to be hotspots with greater SOCD reduction in response to future climate change, and will include lower net plant carbon input due to the negative NPP. Our study indicates that the SOC pool will become a carbon source under increased air temperature and rainfall on the Tibetan Plateau by 2060, especially for the area with vegetation redistribution. These results revealed the potential risk of vegetation redistribution under climate change in alpine ecosystems, indicating the policymakers need to pay attention on the vegetation redistribution to mitigate the soil carbon emission and achieve the goal of carbon neutrality on the Tibetan Plateau.

2.
Water Res ; 202: 117406, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273777

RESUMO

High water turbidity in aquatic ecosystems is a global challenge due to its harmful impacts. A cost-effective manner to rapidly and accurately measure water turbidity is thus of particular useful in water management with limited resources. This study developed a novel framework aiming to predict water turbidity in various aquatic ecosystems. The framework predicted water turbidity and quantified the uncertainty of the prediction through Bayesian modeling. To improve model performance, a model-update method was implemented in the framework to update the model structure and parameters once more measured data were available. 120 paired records (an image from smartphone and a measured water turbidity value by standard turbidimeters for each record) were collected from rivers, lakes and ponds across China to evaluate the performance of the developed framework. Our cross-validation results revealed a well prediction of water turbidity with Nash-Sutcliffe efficiency (NS) >0.87 (p<0.001) during the training period and NS>0.73 (p<0.001) during the validation period. The model-update method (in case of more measured data) for the developed Bayesian models in the framework resulted in a decreasing trend of model uncertainty and a stable mode fit. This study demonstrated a high value of the Bayesian-based framework in predicting water turbidity in a robust and easy manner.


Assuntos
Qualidade da Água , Água , Teorema de Bayes , Ecossistema , Rios
3.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2158-2168, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212622

RESUMO

The research on spatial pattern and optimization of regional ecological carrying capacity is especially necessary to promote the overall development of economic transformation, upgrading and ecological protection and restoration. This study chose the natural, social and economic complex ecosystem of Jiangsu coastal area as subject. The concept model of pressure-state-potential (PSP) of ecological carrying capacity was established. A total of 15 indices were used to represent the interaction of three level states. With the support of GIS and other space technologies, the magnitude, spatial variation of regional ecological carrying capacity were examined through comprehensive evaluation of multiple indices and analysis of single index. Results showed that the spatial pattern of the suitability of single factor ecological carrying capacity in Jiangsu coastal area showed a variety of trends. There were significant differences in the area, proportion and layout of the same index across different cities and counties. The spatial differentiation of pressure and state superposition index showed that low pressure suitable bearing, low pressure generally suitable bearing, low pressure unsuitable bearing, high pressure suitable bearing, high pressure generally suitable bearing, bearing high pressure unsuitable bearing area was 3971.42, 6885.21, 3705.23, 4597.03, 6853.26, and 6403.97 km2, accounting for 12.3%, 21.2%, 11.4%, 14.2%, 21.1% and 19.8% of the total area, respectively. The results of spatial differentiation of superposition index of state and potential showed that the area integral of low potential suitable bearing, low potential general sui-table bearing, low potential unsuitable bearing, high potential suitable bearing, high potential general sui-table bearing and high potential unsuitable bearing was 3030.79, 6545.30, 5874.31, 3253.31, 7614.38, and 6097.83 km2, accounting for 9.4%, 20.2%, 18.1%, 10.0%, 23.5% and 18.8% of the total area, respectively. Most areas showed distribution characteristics of low pressure bearing area corresponding to high potential bearing area and high pressure bearing area corresponding to low potential bearing area in spatial pattern. There was an interaction of mutual influence, mutual promotion and collaborative promotion between pressure and state superposition index and state and potential superposition index.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Cidades , Modelos Teóricos
4.
Sci Total Environ ; 742: 140574, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721731

RESUMO

Environmental factors that drive vegetation change in the Three River Headwater Region (TRHR) on Qinghai-Tibetan Plateau are largely unknown. In particular, the response of alpine grasslands in the TRHR to changing climate and ecological compensations is still poorly understood. Here, we present data on vegetation trends of the TRHR from 1982 to 2015 by employing multiple high-resolution satellite data to determine the mean annual normalized difference vegetation index (NDVI). In addition, spatio-temporal changes in climate were monitored by long-term climate data collection and by using the distributed modeling system. It emerged that: 1) there was a weak increasing trend, albeit not significant, in overall TRHR NDVI, ranging between 0.23 and 0.27; whereas, grassland NDVI ranged between 0.43 and 0.50, and displayed a significant (r2adj = 0.46; P = 0.004) linear increase with year; 2) annual average temperature was below 0 °C and increased linearly (r2adj = 0.60; P = 0.01) at a rate of 0.06 °C/yr from 2000 to 2015, which was almost four times faster than the rate of global warming; and 3) average rainfall was 493 mm/yr, with no significant yearly trend. In conclusion, climate warming enhanced vegetation growth and recovery in the TRHR since 2000; whereas, rainfall did not show a trend. However, vegetation changes on the spatial scale demonstrated zoning and segmentation effects. Consequently, for restoration of degraded lands in the TRHR, effective one-to-one ecological conservation projects, which are particular to an eco-fragile area, should be implemented. In addition, these results are important for regional planning of livestock stocking rates and animal husbandry systems, which can have great impact on the livelihood of the people in the area.


Assuntos
Pradaria , Rios , China , Clima , Mudança Climática , Ecossistema , Temperatura
5.
Transl Psychiatry ; 8(1): 258, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30498208

RESUMO

Antipsychotic pharmacotherapy is strongly obesogenic and is associated with increased oxidative stress in patients with schizophrenia. However, whether these changes reflect psychopathology, antipsychotic efficacy, or some other factor is not known. Our study aims to investigate the degree of oxidative stress in different BMI categories and to identify clinical symptomatology that may be paired with increased oxidative stress in a schizophrenia population. To this end, we performed a cross-sectional study and recruited 89 long-term inpatients with schizophrenia and collected the following variables: plasma malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), routine biochemical analysis, and psychopathology through the Positive and Negative Syndrome Scale (PANSS). The results indicate that the levels of the lipid peroxidation product, MDA, were significantly higher in the high BMI group than the low (normal) BMI group. As expected, high BMI was associated with an atherogenic lipid profile; however, it was also associated with fewer psychopathological symptoms. Multiple regression analysis found that MDA levels, the PANSS general psychopathology subscore, and triglyceride levels (all p < 0.05) were independent contributors to the BMI in patients. These results suggested that oxidative stress may play an important role in antipsychotic-induced weight gain. Further investigations using the longitudinal design in first-episode schizophrenia patients are needed to explore the beneficial effect of antioxidants on the abnormal lipid metabolism mediated by antipsychotic treatment.


Assuntos
Antipsicóticos/efeitos adversos , Obesidade/induzido quimicamente , Obesidade/metabolismo , Estresse Oxidativo , Esquizofrenia/metabolismo , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico
6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(4): 405-8, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17680530

RESUMO

OBJECTIVE: To establish an effective method of genetic diagnosis on hemophilia A (HA) by detecting the inversion mutation in intron 22 of F8 gene. METHODS: Intron 22 inversion mutation in F8 gene was detected by using long distance-polymerase chain reaction (LD-PCR) and inversion-PCR (I-PCR) in 31 HA patients. The mothers of HA patients with intron 22 inversion mutation were selected to carrier diagnosis and amniotic fluid of the pregnant women with inversion mutation was collected at intermediate stage of gestation, and used to prenatal genetic diagnosis. RESULTS: Seven patients showed F8 gene inversion mutation in thirty-one patients. Three in four mothers of HA patients with intron 22 inversion mutation were diagnosed as carriers. The prenatal diagnosis result indicated that the fetus conceived in the HA-carrier woman was normal individual. CONCLUSION: The detection of intron 22 inversion mutation by LD-PCR and I-PCR is time-saving, and can be used in prenatal diagnosis on HA.


Assuntos
Fator VIII/genética , Hemofilia A/diagnóstico , Hemofilia A/genética , Diagnóstico Pré-Natal/métodos , Feminino , Humanos , Íntrons/genética , Mutação , Reação em Cadeia da Polimerase/métodos , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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