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1.
Huan Jing Ke Xue ; 45(5): 2793-2805, 2024 May 08.
Article in Chinese | MEDLINE | ID: mdl-38629542

ABSTRACT

The purpose of this study was to reveal the spatial and temporal evolution patterns of habitat quality in karst counties of Guizhou plateau and its driving factors and to provide scientific basis for balanced ecological conservation and sustainable development of karst regions. Using DEM data, meteorological data, socio-economic data, and four periods of land use data in 1989, 2003, 2010, and 2020, the InVEST model was used to analyze the spatial and temporal evolution characteristics of habitat quality in Puding County from 1989 to 2020 and to quantitatively detect the driving forces of its spatial divergence. The results were as follows:① Arable land and forest land were the main land use types in Puding County, which constituted the surface cover landscape matrix. Land use changes from 2003-2010 were the most significant, among which forest land had the largest increase of 86.42%; arable land was the most severely lost land use type, with an area decrease of 157.57 km2, mainly flowing to forest land and construction land. ② From 1989 to 2020, the average value of habitat quality index in Puding County increased from 0.60 to 0.73. Spatially, the distribution pattern of "high-low-high" was generally from northeast to southwest, with the high value areas of habitat quality mainly distributed in the woodland and grassland areas in the northeast and the low value areas concentrated in the construction land in the central and south areas. ③ Land use type was the primary factor affecting the spatial and temporal distribution of habitat quality, with an explanation of 91.00%. In the interaction detection, the interaction of any two influencing factors was greater than that of individual factors alone, and the interaction between land use type and average annual precipitation was the strongest, reaching 96.00%; the interaction with lithological factors reached 94.00%, with natural and human factors jointly dominating the spatial and temporal changes in habitat quality. From the results of this study, we concluded that the habitat quality of Puding County was generally good from 1989 to 2020, and the relationship between land use type changes and habitat quality was close. Optimizing the land use structure and reducing the influence of human activities are important to improve the habitat quality of Puding County.

2.
J Environ Manage ; 351: 119796, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38081084

ABSTRACT

Stated preference valuation of ecosystem services involves participants answering hypothetical questions to express preferences. Participants tend to respond to the hypothetical questions separately, without any deliberation (the process of considering and discussing within a group). However, a relatively recent development in deliberation research involves asking participants to state preferences via deliberation. Deliberation is historically conducted in-person but can now also be done online. This paper covers the strengths and limitations of integrating online deliberation into stated preference valuation, including: (1) comparison between stated preference valuation with and without deliberation, (2) comparison between in-person and online deliberation, and (3) comparison between online deliberation media, such as typing, video meetings, and voice calls. Conducting deliberation can broaden participants' understanding of the target ecosystem services and others' preferences. However, this requires participants' willingness to deliberate and increases time investment. Online deliberation has lower costs and travel restrictions and higher time efficiency and confidentiality of personal information than in-person deliberation. However, people with low abilities or willingness to use online media are disadvantaged. Differences in the online deliberation media may reduce or improve the inclusiveness, engagement, and openness of deliberations in ways that affect valuation results. We also provide suggestions for selecting deliberation media and mitigating deliberation bias derived from the choice of deliberation media. Further research should explore how to improve time efficiency and affordability of online deliberation, how to promote inclusiveness, engagement, and openness of online deliberation, and how different deliberation media affect deliberation quality and valuation results.


Subject(s)
Ecosystem , Costs and Cost Analysis
3.
Sci Total Environ ; 887: 163911, 2023 Aug 20.
Article in English | MEDLINE | ID: mdl-37149175

ABSTRACT

Karst ecosystems are important to several billion people, so it is necessary to accurately diagnose and evaluate the health of these ecosystems for socioeconomic development; however, the existing evaluation methods have many limitations, so they cannot accurately evaluate the ecosystem health in karst areas. In particular, they ignore the influence and restriction of the soil formation rate on the ecosystem health. To this end, we established a new index to represent the actual health status of karst ecosystems. The soil formation rate was found to pose a threat to the health of 28 % of the world's karst ecosystems, covering an area of 594 km2. In addition, a dataset of global karst ecosystem health index values with a spatial resolution of about 8 km × 8 km from 2000 to 2014 was created, and the proportion of unhealthy areas was found to be as high as 75.91 %. This study highlights the contribution of the soil formation rate to karst ecosystem health and provides a new method and deeper scientific understanding for further accurate evaluation of karst ecosystem health, which can improve future ecosystem health research and social management.


Subject(s)
Ecosystem , Soil , Humans , Soil Microbiology , China
4.
Sci Rep ; 12(1): 19121, 2022 11 09.
Article in English | MEDLINE | ID: mdl-36352040

ABSTRACT

Karst rocky desertification (KRD) has become one of the most serious ecological and environmental problems in karst areas. At present, mapping KRD with a high accuracy and on a large scale is still a difficult problem in the control of KRD. In this study, a random forest (RF) based on maximum information coefficient and correlation coefficient feature selection is proposed to predict KRD. Nine predictors stood out as feature factors to estimate KRD. Rock exposure was the most important predictor, followed by fractional vegetation cover for the prediction of KRD processes. The kappa and classification accuracy indexes were to evaluate the performance of the model. We recorded overall accuracy rate and kappa index values of 94.7% and 0.92 for the testing datasets respectively. The RF model was then used to predict the KRD in 2001, 2011, 2016, and 2020, and it was found that the KRD in the study area has exhibited a positive trend of improvement. Therefore, the use of multisource remote sensing data combined with the RF model can obtain better prediction results of KRD, thereby providing a new idea for large-scale estimation of the KRD in peak-cluster depression.


Subject(s)
Conservation of Natural Resources , Ecosystem , Conservation of Natural Resources/methods , Depression , China , Machine Learning
5.
Article in English | MEDLINE | ID: mdl-36231869

ABSTRACT

Human well-being in many countries lags behind the gross domestic product (GDP) due to the rapid changes in the socio-economic environment that have occurred for decades. However, the mechanisms behind this complex phenomenon are still unclear. This study revealed the changes in human well-being in China from 1995 to 2017 by revising the genuine progress indicator (GPI) at the national level and further quantified the contribution of interfering factors that have driven the increase in the GPI. The results indicated that: (1) The per capita GPI of China showed an increasing trend with an annual growth rate of 12.43%. The changes in the GPI followed the same pattern as economic development, rather than presenting the phenomenon of economic growth combined with a decline in welfare that has been recorded in some countries and regions. (2) The increase in human well-being was mainly driven by economic growth, but it was most sensitive to social factors. (3) Increasing income inequality and the cost of lost leisure time contributed obvious negative impacts (24.69% and 23.35%, respectively) to the per capita GPI. However, the increase in personal consumption expenditures, the value of domestic labor, ecosystem service value, and net capital growth accelerated the rise in the GPI, with positive contribution rates of 30.69%, 23%, 20.54%, and 20.02%, respectively. (4) The continuous increase in economic investment and the strengthening of social management due to policy adjustments completely counteracted the negative impacts on human well-being, thus leading to a great increase in the per capita GPI. Such insights could provide theoretical support for decision making and policy implementation to improve global human well-being.


Subject(s)
Economic Development , Ecosystem , China , Gross Domestic Product , Humans , Policy
6.
Glob Chang Biol ; 28(14): 4377-4394, 2022 07.
Article in English | MEDLINE | ID: mdl-35366362

ABSTRACT

Climatic and non-climatic factors affect the chemical weathering of silicate rocks, which in turn affects the CO2 concentration in the atmosphere on a long-term scale. However, the coupling effects of these factors prevent us from clearly understanding of the global weathering carbon sink of silicate rocks. Here, using the improved first-order model with correlated factors and non-parametric methods, we produced spatiotemporal data sets (0.25° × 0.25°) of the global silicate weathering carbon-sink flux (SCSFα ) under different scenarios (SSPs) in present (1950-2014) and future (2015-2100) periods based on the Global River Chemistry Database and CMIP6 data sets. Then, we analyzed and identified the key regions in space where climatic and non-climatic factors affect the SCSFα . We found that the total SCSFα was 155.80 ± 90 Tg C yr-1 in present period, which was expected to increase by 18.90 ± 11 Tg C yr-1 (12.13%) by the end of this century. Although the SCSFα in more than half of the world was showing an upward trend, about 43% of the regions were still showing a clear downward trend, especially under the SSP2-4.5 scenario. Among the main factors related to this, the relative contribution rate of runoff to the global SCSFα was close to 1/3 (32.11%), and the main control regions of runoff and precipitation factors in space accounted for about 49% of the area. There was a significant negative partial correlation between leaf area index and silicate weathering carbon sink flux due to the difference between the vegetation types. We have emphasized quantitative analysis the sensitivity of SCSFα to critical factors on a spatial grid scale, which is valuable for understanding the role of silicate chemical weathering in the global carbon cycle.


Subject(s)
Carbon Dioxide , Carbon Sequestration , Carbon Dioxide/analysis , Rivers , Silicates/analysis , Weather
7.
Sci Total Environ ; 810: 151209, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34748828

ABSTRACT

Vegetation changes in karst areas are controlled by the soil formation rate (SFR) and soil moisture (SM). However, little is known about their thresholds and global control patterns. To this end, based on high-precision climate and vegetation data for 2000-2014, using Pearson correlation analysis, the Hurst index, and change-point analysis, the thresholds of the SFR and SM in vegetation growth in karst areas were identified. Furthermore, a spatial map (0.125° × 0.125°) of the global karst ecosystem with a static/dynamic limitation zone was established. We found that the net primary productivity (NPP) in 70% of the global climate zones exhibited a dual restriction relationship with the SM and SFR. The limitations of the SFR and SM in vegetation growth were most obvious in subpolar and semi-arid climates. In addition, their ecological thresholds were 25.2 t km-2 yr-1 and 0.28 m3 m-3, respectively. The static limitation of the SFR on the NPP in karst areas accounted for 28.37%, and the influence of the SM enhanced this limit (21.79%). The limitation of the SFR on vegetation was mainly concentrated in Boreal forests (17%), and the limitation of the SM was mainly concentrated in tropical savannas (12%). The NPP and the Normalized Difference Vegetation Index (NDVI) were the most sensitive to changes in the SM and SFR. Moreover, the analysis based on 14 ecologically limitation karst areas further revealed that the reduction in these factors may cause the tropical rain forest to experience degradation. It can be seen that the SM enhanced the limiting effect of the SFR on vegetation in karst areas. In short, this interpretation of karst vegetation limitations provides a deeper understanding of and approach to ecosystem evolution and vegetation restoration in these regions.


Subject(s)
Ecosystem , Soil , China , Desert Climate
8.
Sci Total Environ ; 788: 147706, 2021 Sep 20.
Article in English | MEDLINE | ID: mdl-34023608

ABSTRACT

Eco-hydrological processes affect the chemical weathering carbon sink (CS) of rocks. However, due to data quality limitations, the magnitude of the CS of rocks and their responses to eco-hydrological processes are not accurately understood. Therefore, based on Global Erosion Model for CO2 fluxes (GEM-CO2 model), hydrological site data, and multi-source remote sensing data, we produced a 0.05° × 0.05° resolution dataset of CS for 11 types of rocks from 2001 to 2018. The results show that the total amount of CS of global rocks is 0.32 ± 0.02 Pg C, with an average flux of 2.7 t C km-2 yr-1, accounting for 53% and 3% of the "missing" carbon sink and fossil fuel emissions, respectively. This is 23% higher than previous research results, which may be due to the increased resolution. Although about 60% of the CS of global rocks are in a stable state, there are obvious differences among rocks. For example, the CS of carbonate rocks exhibited a significant increase (0.30 Tg C/yr), while the CS of siliceous clastic sedimentary rocks exhibited a significant decrease (-0.06 Tg C/yr). Although temperature is an important factor affecting the CS, the proportion of soil moisture in arid and temperate climate zones is higher (accounting for 24%), which is 3.6 times that of temperature. Simulations based on representative concentration pathways scenarios indicate that the global CS of rocks may increase by about 28% from 2050 to 2100. In short, we produced a set of high-resolution datasets for the CS of global rocks, which makes up for the lack of datasets in previous studies and improves our understanding of the magnitude and spatial pattern of the CS and its responses to eco-hydrological processes.

9.
Sci Total Environ ; 750: 141525, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-32858291

ABSTRACT

The weathering carbon sink (CS) of rocks has a sensitive response to different influencing factors, and it is important to accurately distinguish this response in the global carbon cycle. However, no quantitative analysis of the response mechanism has been performed. In this study, the CS of the 12 types of terrestrial rocks in China from 2000 to 2014 is estimated using the GEM-CO2 model. The relative contribution rates of climate change and ecological restoration to the CS are quantitatively evaluated using the Lindeman-Merenda-Gold model. Results showed that: (1) The CS of terrestrial rocks in China was 17.69 Tg C yr-1, and the CS flux (CSF) was 2.53 t C km-2 yr-1; mixed sedimentary rocks had the highest CS (6.89 Tg C yr-1), and carbonate rocks had the highest CSF (5.8 t C km-2 yr-1). (2) The average annual CSF slightly decreased at a rate of 5.4 kg C km-2 yr-1; the areas of the CSF that decreased in the south were the areas where water budget decreased significantly, and it was the areas with a reduced water budget and ecological deterioration in the north. (3) The relative contribution rates of water budget and precipitation reached 57% and 35%, respectively; the response of the CSF to temperature was evident in areas with low or decreasing temperatures, and the influence of fractional vegetation cover (FVC) on the CSF in low value area was evident. (4) Mixed sedimentary rocks and carbonate rocks displayed a more evident reduction trend in the CSF than other rocks. This research verified the applicability of the GEM-CO2 model in China and presented a scientific basis for quantitative assessment of the impact of climate change and ecological restoration on the CSF.

10.
J Proteome Res ; 18(5): 2321-2330, 2019 05 03.
Article in English | MEDLINE | ID: mdl-30966751

ABSTRACT

Dry eye syndrome (DES) is a growing public health concern with a high global prevalence; however, the fundamental processes involved in its pathogenic mechanisms remain poorly understood. In the present study, we applied nanoscale liquid chromatography and quadrupole time-of-flight tandem mass spectrometry (nanoLC/Q-TOF-MS/MS) and ultraperformance LC/Q-TOF-MS/MS technologies on tear samples obtained from 18 dry eye patients and 19 healthy controls for integrated proteomic and metabolomic analyses. Overall, 1031 tear proteins were detected, while 190 proteins were determined to be significantly expressed in dry eye patients. Further functional analysis suggested that various biological processes were highly expressed and involved in the pathogenesis of DES, especially immune and inflammatory processes. In total, 156 named metabolites were identified, among which 34 were found to be significantly changed in dry eye patients. The results highlighted the key elements, especially inflammatory-related proteins and metabolites that played important roles in the development of DES. Further, the regulatory roles of primary pathways, including complement and coagulation cascades, glycolysis/gluconeogenesis, and amino acid metabolism, were also identified as processes involved in DES. Collectively, our work not only provided insight into the potential biomarkers of DES for diagnostic and prognostic purposes but extended our knowledge of the physiopathology of this syndrome.


Subject(s)
Complement System Proteins/genetics , Dry Eye Syndromes/genetics , Eye Proteins/genetics , Metabolome , Proteome/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Amino Acids/metabolism , Case-Control Studies , Chromatography, Liquid , Complement System Proteins/classification , Complement System Proteins/metabolism , Dry Eye Syndromes/metabolism , Dry Eye Syndromes/physiopathology , Eye Proteins/classification , Eye Proteins/metabolism , Female , Gene Expression Regulation , Gene Regulatory Networks , Gluconeogenesis/genetics , Glycolysis/genetics , Humans , Male , Middle Aged , Protein Interaction Mapping , Proteome/classification , Proteome/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tears/chemistry
11.
Sci Total Environ ; 643: 157-170, 2018 Dec 01.
Article in English | MEDLINE | ID: mdl-29936159

ABSTRACT

The magnitudes, spatial distributions and contributions to global carbon budget of the global carbonate carbon sink (CCS) still remain uncertain, allowing the problem of national measurement of CCS remain unresolved which will directly influence the fairness of global carbon markets and emission trading. Here, based on high spatiotemporal resolution ecological, meteorological raster data and chemical field monitoring data, combining highly reliable machine learning algorithm with the thermodynamic dissolution equilibrium model, we estimated the new CCS of 0.89 ±â€¯0.23 petagrams of carbon per year (Pg C yr-1), amounting to 74.50% of global net forest sink and accounting for 28.75% of terrestrial sinks or 46.81% of the missing sink. Our measurement for 142 nations of CCS showed that Russia, Canada, China and the USA contribute over half of the global CCS. We also presented the first global fluxes maps of the CCS with spatial resolution of 0.05°, exhibiting two peaks in equatorial regions (10°S to 10°N) and low latitudes (10°N to 35°N) in Northern Hemisphere. By contrast, there are no peaks in Southern Hemisphere. The greatest average carbon sink flux (CCSF), i.e., 2.12 tC ha-1 yr-1, for 2000 to 2014 was contributed by tropical rainforest climate near the equator, and the smallest average CCSF was presented in tropical arid zones, showing a magnitude of 0.26 tC ha-1 yr-1. This research estimated the magnitudes, spatial distributions, variations and contributions to the global carbon budget of the CCS in a higher spatiotemporal representativeness and expandability way, which, via multiple mechanisms, introduced an important sink in the terrestrial carbon sink system and the global missing sink and that can help us further reveal and support our understanding of global rock weathering carbon sequestration, terrestrial carbon sink system and global carbon cycle dynamics which make our understanding of global change more comprehensive.

12.
Sci Rep ; 8(1): 641, 2018 01 12.
Article in English | MEDLINE | ID: mdl-29330526

ABSTRACT

Land surface temperature (LST) can reflect the land surface water-heat exchange process comprehensively, which is considerably significant to the study of environmental change. However, research about LST in karst mountain areas with complex topography is scarce. Therefore, we retrieved the LST in a karst mountain area from Landsat 8 data and explored its relationships with LUCC and NDVI. The results showed that LST of the study area was noticeably affected by altitude and underlying surface type. In summer, abnormal high-temperature zones were observed in the study area, perhaps due to karst rocky desertification. LSTs among different land use types significantly differed with the highest in construction land and the lowest in woodland. The spatial distributions of NDVI and LST exhibited opposite patterns. Under the spatial combination of different land use types, the LST-NDVI feature space showed an obtuse-angled triangle shape and showed a negative linear correlation after removing water body data. In summary, the LST can be retrieved well by the atmospheric correction model from Landsat 8 data. Moreover, the LST of the karst mountain area is controlled by altitude, underlying surface type and aspect. This study provides a reference for land use planning, ecological environment restoration in karst areas.

13.
Sci Total Environ ; 601-602: 1449-1465, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28605863

ABSTRACT

The Yinjiang River watershed is a typical karst watershed in Southwest China. The present study explored runoff change and its responses to different driving factors in the Yinjiang River watershed over the period of 1984 to 2015. The methods of cumulative anomaly, continuous wavelet analysis, Mann-Kendall rank correlation trend test, and Hurst exponent were applied to analyze the impacts of climate change and human activities on runoff change. The contributions of climate change and human activities to runoff change were quantitatively assessed using the comparative method of the slope changing ratio of cumulative quantity (SCRCQ). The following results were obtained: (1) From 1984 to 2015, runoff and precipitation exhibited no-significant increasing trend, whereas evaporation exhibited significant decreasing trend. (2) In the future, runoff, precipitation, and evaporation will exhibit weak anti-persistent feature with different persistent times. This feature indicated that in their persistent times, runoff and precipitation will continuously decline, whereas evaporation will continuously increase. (3) Runoff and precipitation were well-synchronized with abrupt change features and stage characteristics, and exhibited consistent multi-timescale characteristics that were different from that of evaporation. (4) The contribution of precipitation to runoff change was 50%-60% and was considered high and stable. The contribution of evaporation to runoff change was 10%-90% and was variable with a positive or negative effects. The contribution of human activities to runoff change was 20%-60% and exerted a low positive or negative effect. (5) Climatic factors highly contributed to runoff change. By contrast, the contribution of human activities to runoff change was low. The contribution of climatic factors to runoff change was highly variable because of differences among base periods. In conclusion, this paper provides a basic theoretical understanding of the main factors that contribute to runoff change in a karst watershed.


Subject(s)
Climate Change , Environmental Monitoring , Human Activities , Water Movements , China , Humans , Rivers
14.
Int J Clin Pharmacol Ther ; 55(2): 126-132, 2017 02.
Article in English | MEDLINE | ID: mdl-27117036

ABSTRACT

AIMS: To investigate whether genetic variants of CYP2C9 and VKORC1 have different effects on the dose of warfarin in 180 Han Chinese patients who were recruited from the Fu Wai Hospital. All were on maintenance treatment with stable daily warfarin doses for a period of at least 3 months. METHODS: DNA was isolated and genotyped using a Warfarin dosage Prediction Kit for single nucleotide polymorphisms (SNPs) of CYP2C9 and VKORC1. RESULTS: The VKORC1 and CYP2C9*3 polymorphisms are significantly associated with warfarin maintenance dosages. Patients with AG&GG genotype in VKORC1 needed higher doses than those with AA genotypes (4.55 ± 1.27 mg/ day vs. 2.90 ± 0.97 mg/day, p < 0.001). Patients with *1/*3 genotype in CYP2C9 need doses lower than those with *1/*1 genotypes (1.73 ± 0.95 mg/day vs. 3.23 ± 1.13 mg/day, p < 0.001). There were no significant differences between the warfarin maintenance dosages in patients with atrial fibrillation (3.09 ± 1.16 mg/day), patients with heart valve replacement (2.95 ± 1.21 mg/day) and those with both atrial fibrillation and heart valve replacement (3.36 ± 1.13 mg/day) (p > 0.05). The mean warfarin daily dose requirements in the genotypes of VKORC1 and CYP2C9 were not dependent on the medical indication(s) present. CONCLUSIONS: Genetic variants of CYP2C9, VKORC1, and age are significant determinants of the maintenance dose of warfarin. The medical indications atrial fibrillation, valve replacement, or a combination of both are not determinants of the warfarin dose requirements.


Subject(s)
Anticoagulants/administration & dosage , Aortic Valve/surgery , Cytochrome P-450 CYP2C9/genetics , Drug Dosage Calculations , Heart Valve Prosthesis Implantation/adverse effects , Pharmacogenomic Variants , Polymorphism, Single Nucleotide , Stroke/prevention & control , Thrombosis/prevention & control , Vitamin K Epoxide Reductases/genetics , Warfarin/administration & dosage , Adult , Aged , Blood Coagulation/drug effects , China , Cytochrome P-450 CYP2C9/metabolism , Female , Humans , International Normalized Ratio , Linear Models , Male , Middle Aged , Multivariate Analysis , Pharmacogenetics , Phenotype , Stroke/diagnosis , Stroke/etiology , Thrombosis/diagnosis , Thrombosis/etiology , Treatment Outcome , Vitamin K Epoxide Reductases/metabolism
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