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2.
Sci Total Environ ; 802: 149812, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455275

RESUMO

While ubiquitous natural organic matters (NOMs) are capable of enhancing zero-valent iron (ZVI) performance under aerobic conditions, there is limited understanding of how the properties of NOMs affect the reactivity of ZVI towards contaminants removal. Here, the corresponding activity of ZVI under aerobic conditions was investigated in the presence of humic acid (HA), fulvic acid (FA), bovine serum albumin (BSA). It was found that three models of NOMs were all effective in promoting diatrizoate (DTA) reduction via depassivating ZVI. Interestingly, fast adsorption of NOM onto ZVI surface initially caused inconspicuous impact or visible inhibition on hydrophilic DTA reduction depending on their hydrophobicity. However, subsequent exposure of more reactive sites with high hydrophilicity arising from the detachment of surfaced NOM-associated iron oxide finally contributed to the enhanced consumption of Fe0 with the ability: HA > FA ≈ BSA, and 1-2 times increase in DTA removal kinetic rate following the order: HA > FA > BSA. It further revealed that there were two key factors in determining DTA removal under aerobic conditions, including the ability of NOMs to boost Fe0 consumption as contributed by their aromaticity degree and amino groups, and the hydrophobicity of NOMs to initially affect the property of ZVI surfaces.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Adsorção , Substâncias Húmicas/análise , Ferro , Poluentes Químicos da Água/análise
3.
Front Med (Lausanne) ; 8: 649408, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722555

RESUMO

Psoriasis is a chronic multisystem inflammatory disease that affects ~0.1-1.5% of the world population. The classic cutaneous manifestation of psoriasis is scaly erythematous plaques, limited or widely distributed. Moreover, psoriasis could be associated with comorbidities like psoriatic arthritis, metabolic syndrome, diabetes, cardiovascular disease, nephropathy, bowel disease, and brain diseases. In this review, we suggest that psoriasis should be classified as cutaneous psoriasis or systemic psoriasis and propose the classification for distinction. This would help to better understand and manage psoriasis.

4.
Opt Express ; 29(21): 33109-33120, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809129

RESUMO

We demonstrate a high linear polarization, narrow linewidth hybrid laser composed of a semiconductor gain chip and a high birefringence waveguide Bragg grating (WBG). The laser operates in the C-band, and a maximum output power of 8.07 mW is obtained in the fiber waveguide. With careful temperature tuning, the hybrid laser can operate in a single longitudinal mode state from above the threshold current to 410 mA. The side mode suppression ratio (SMSR) reaches a value of 50.2 dB, and the polarization extinction ratio exceeds 39.6 dB. We numerically analyze the linewidth suppression for the Bragg grating based on adiabatic chirp theory. The hybrid laser shows a narrow linewidth of 4.15 kHz and a low relative intensity noise (RIN) of <-155 dBc/Hz, providing a high-performance light source for coherent light communication.

5.
N Engl J Med ; 385(22): 2077, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34797615
6.
Front Med ; 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34741701

RESUMO

Whether Fanconi anemia (FA) heterozygotes are predisposed to bone marrow failure and hematologic neoplasm is a crucial but unsettled issue in cancer prevention and family consulting. We retrospectively analyzed rare possibly significant variations (PSVs) in the five most obligated FA genes, BRCA2, FANCA, FANCC, FANCD2, and FANCG, in 788 patients with aplastic anemia (AA) and hematologic malignancy. Sixty-eight variants were identified in 66 patients (8.38%). FANCA was the most frequently mutated gene (n = 29), followed by BRCA2 (n = 20). Compared with that of the ExAC East Asian dataset, the overall frequency of rare PSVs was higher in our cohort (P = 0.016). BRCA2 PSVs showed higher frequency in acute lymphocytic leukemia (P = 0.038), and FANCA PSVs were significantly enriched in AA and AML subgroups (P = 0.020; P = 0.008). FA-PSV-positive MDS/AML patients had a higher tumor mutation burden, higher rate of cytogenetic abnormalities, less epigenetic regulation, and fewer spliceosome gene mutations than those of FA-PSV-negative MDS/AML patients (P = 0.024, P = 0.029, P = 0.024, and P = 0.013). The overall PSV enrichment in our cohort suggests that heterozygous mutations of FA genes contribute to hematopoietic failure and leukemogenesis.

7.
Plant Physiol Biochem ; 167: 1035-1048, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34600181

RESUMO

Lonicera japonica Thunb. is widely used in traditional medicine systems of East Asian and attracts a large amount of studies on the biosynthesis of its active components. Currently, there is little understanding regarding the regulatory mechanisms behind the accumulation of secondary metabolites during its developmental stages. In this study, published transcriptomic and proteomic data were mined to evaluate potential linkage between protein modification and secondary metabolism during the floral development. Stronger correlations were observed between differentially expressed genes (DEGs) and their corresponding differentially abundant proteins (DAPs) in the comparison of juvenile bud stage (JBS)/third green stage (TGS) vs. silver flowering stage (SFS). Seventy-five and 76 cor-rDEGs and cor-rDAPs (CDDs) showed opposite trends at both transcriptional and translational levels when comparing their levels at JBS and TGS relative to those at SFS. CDDs were mainly involved in elements belonging to the protein metabolism and the TCA cycle. Protein-protein interaction analysis indicated that the interacting proteins in the major cluster were primarily involved in TCA cycle and protein metabolism. In the simple phenylpropanoids biosynthetic pathway of SFS, both phospho-2-dehydro-3-deoxyheptonate aldolase (PDA) and glutamate/aspartate-prephenate aminotransferase (AAT) were decreased at the protein level, but increased at the gene level. A confirmatory experiment indicated that protein ubiquitination and succinylation were more prominent during the early floral developmental stages, in correlation with simple phenylpropanoids accumulation. Taken together, those data indicates that phenylpropanoids metabolism and floral development are putatively regulated through the ubiquitination and succinylation modifications of PDA, AAT, and TCA cycle proteins in L. japonica.


Assuntos
Lonicera , Flores , Processamento de Proteína Pós-Traducional , Proteômica , Metabolismo Secundário
8.
Ecol Evol ; 11(18): 12583-12595, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34594522

RESUMO

Geological events, landscape features, and climate fluctuations have shaped the distribution of genetic diversity and evolutionary history in freshwater fish, but little attention has been paid to that around the Gulf of Tonkin; therefore, we investigated the phylogeographic structure of the dwarf snakehead (Channa gachua) on Hainan Island and mainland China, as well as two populations in Vietnam. We attempted to elucidate the origins of freshwater fish in South Hainan by incorporating genetic data from DNA markers on both the mitochondrial cytochrome b gene (cyt b) and the nuclear recombination-activating gene 1 (RAG-1). Mitochondrial phylogenetic analysis identified two major lineages (lineages A and B), which may represent separate species. Divergence data suggested that C. gachua populations diverged between 0.516 and 2.376 myr. The divergence of the two cryptic species is congruent with sea-level rise, which subsequently isolated Hainan from the mainland. During the Pleistocene glaciations, the entire region of the Gulf of Tonkin and the Qiongzhou Strait became part of the coastal plain of the Asian continent, which might have resulted in the current distribution patterns and dispersal routes of C. gachua populations. The formation of three sublineages in lineage A indicated that the Gulf of Tonkin was a geographical barrier between Hainan Island and mainland China but not between Vietnam and Hainan Island. The results of this study may help to elucidate the origins of freshwater fish in South Hainan and the phylogeographic structure of C. gachua.

9.
Front Mol Biosci ; 8: 720370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568426

RESUMO

Purpose: Despite considerable efforts to improve treatment modalities for cholangiocarcinoma, a common form of malignant tumor, its long-term survival rate remains poor. Hydroxychloroquine (HCQ) is a 4-aminoquinoline derivative antimalarial drug that has antimalarial and autophagy inhibition effects and exhibits comprehensive therapeutic effects on various cancers. In this study, we aimed to explore the anticancer potential and the underlying molecular mechanism of HCQ in cholangiocarcinoma treatment in vitro and in vivo. Methods: Autophagy-related genes (ARGs) were obtained from the Human Autophagy Database and Molecular Signatures Database, and the expression profiles of ARGs were downloaded from the database of The Cancer Genome Atlas. Different expression gene sets were performed using R software. The Gene Ontology and KEGG enrichment analyses were performed to reveal significantly enriched signaling pathways and to identify differentially expressed genes in cholangiocarcinoma tissues. HuCCT-1 and CCLP-1 cells were exposed to different concentrations of HCQ. Cell proliferation was detected by Cell Counting Kit-8 (CCK-8), colony formation, and 5-ethynyl-2'-deoxyuridine (EdU) assays. Cell apoptosis and cycle arrest were detected by the Live/Dead cell assay and flow cytometry (FCM). The inhibition of autophagy was observed using fluorescence microscopy. The reactive oxygen species levels were assessed by fluorescence microscopy and flow cytometry. The protein levels were determined by western blot. A cholangiocarcinoma cell line xenograft model was used to evaluate the antitumor activity of HCQ in vivo. Results: Compared with normal tissues, there were 141 ARGs with an aberrant expression in cholangiocarcinoma tissues which were mainly enriched in autophagy-related processes. Inhibition of autophagy by HCQ effectively suppressed cholangiocarcinoma in vitro and in vivo. HCQ inhibited cell proliferation and induced apoptosis and cycle arrest in vitro by increasing ROS accumulation, which was involved in autophagy inhibition. The ROS scavenger reduced l-glutathione distinctly weakened HCQ-induced cell apoptosis and viability inhibition in cholangiocarcinoma cells. In addition, HCQ inhibited growth of cholangiocarcinoma cell line xenograft tumors. Conclusion: HCQ could inhibit cell proliferation and induce apoptosis in cholangiocarcinoma by triggering ROS accumulation via autophagy inhibition, which makes HCQ a potential antitumor drug candidate for cholangiocarcinoma treatment.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34531543

RESUMO

Graft-versus-host disease (GVHD) is a critical complication after allogeneic haematopoietic stem cell transplantation induced by genetic differences in donor-recipient pairs. Rigorous HLA matching has reduced GVHD, but severe GVHD still occurs. Minor histocompatibility antigens (mHAs) are another source of GVHD inducers. We designed a multi-mHA panel with 35 valid mHA loci and retrospectively analyzed 391 donor-recipient pairs with the anticipation of implementing mHA typing into clinical practice to optimize donor selection. Results showed the total mismatching in mHA loci in this panel, as well as mismatching in the GVH direction in unmatched-related recipients (UMRs) were 1.8 times and 1.3 times as those in matched-sibling recipients (MSRs) (p = 4.1e-4, p = 0.012, respectively). There was no significant association between mHA loci mismatching and grades II-IV acute GVHD (aGVHD), III-IV aGVHD, extensive chronic GVHD (cGVHD), or relapse in neither group. UMRs had an increased cumulative incidence of II-IV aGVHD (p = 0.002), but there was no statistical difference of the incidences in severe aGVHD or cGVHD (p = 0.093; p = 0.930). This is a preliminary study to explore GVHD risks brought by mHA loci mismatching in both unmatched-related recipients and matched-full-sibling recipients. Our results confirmed that stringent HLA matching is the key to reduce the risks for GVHD.

11.
Inorg Chem ; 60(18): 14467-14474, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34495661

RESUMO

In this work, a tunable luminescence color from yellow to orange of photoluminescence (PL), long persistent luminescence (LPL), and photostimulated luminescence (PSL) is successfully achieved in BaGa2O4:Bi3+ phosphors with the introduction of Sr2+ ions as secondary cations. It is confirmed that broad-band emissions located at 500 and 600 nm originate from the occupation of Bi3+ ions at different lattice sites in the BaGa2O4 host matrix. The replacement of Sr2+ for Ba2+ ions makes the emission red-shift from 600 to 650 nm; moreover, two additional emissions appeare at 743 and 810 nm due to the occupational preference of Bi3+ ions at Ga3+ sites. Furthermore, the doped Sr2+ ions promote the reconstruction of the trapping centers, which conduces to the fundamental improvement of the optical storage capacity behavior of Bi3+-doped phosphors. Our results clarify the dependence of the luminescence performance on the crystal sites of Bi3+ ions with fascinating broad-band emissions in the BaGa2O4:0.01Bi3+ host matrix and will benefit the design and exploration of Bi3+-doped solid solutions for optical storage applications.

12.
Plants (Basel) ; 10(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34579353

RESUMO

7-hydroxymethyl chlorophyll (Chl) a reductase (HCAR) plays critical roles in the Chl cycle and degradation during leaf senescence, however, its function in horticultural crops remains unknown. Here, we identified an HCAR gene (CsHCAR) from cucumber (Cucumis sativus L.) and investigated its roles in response to dark-induced Chl degradation. CsHCAR encoded 459 amino acids, which were orthologous to Arabidopsis HCAR, had the conserved domains, and localized in the chloroplast. Gene expression analysis showed that CsHCAR expression was the highest in senescent leaves and was responsive to different stresses and phytohormone treatments. Overexpression of CsHCAR in tobacco accelerated dark-induced Chl degradation through enhancing the expression of Chl catabolic genes. After 10 d of darkness treatment, the biomass of CsHCAR overexpression plants was reduced. Furthermore, the value of net photosynthetic rate, maximum quantum yield of photosystem II, and effective quantum yield of photosystem II in CsHCAR overexpression plants was significantly reduced in comparison to that in wild-type (WT) plants. The photosynthetic protein content, including Lhcb1, Lhcb2, Lhcb4, RbcS, and RbcL in CsHCAR overexpression plants exhibited a lower level as compared to that observed in WT plants. In addition, the expression of genes encoding these proteins in CsHCAR overexpression plants was significantly lower than that in WT plants. Moreover, CsHCAR overexpression plants inhibited the dark-induced accumulation of reactive oxygen species (ROS). These results indicate that CsHCAR affects the stability of photosynthetic proteins in chloroplasts, positively regulates Chl degradation, and plays an important role in maintaining ROS homeostasis in leaves.

13.
Pain Ther ; 10(2): 1051-1066, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34537952

RESUMO

Although thoracoscopy has characteristics such as a small surgical incision and low stress response, post-surgical pain after a thoracoscopic operation is no less than that after a thoracotomy. Moreover, poor post-surgical pain management is likely to cause an increased incidence of postoperative pulmonary complications (PPCs) and chronic post-surgical pain. The serratus anterior plane block (SAPB) is a regional anesthesia method whereby local anesthetics (LAs) are injected into the serratus anterior space to block the lateral cutaneous branch of the intercostal nerve, long thoracic nerve, and dorsal thoracic nerve. The block range of the SAPB covers the incisions of video-assisted thoracoscopic surgery (VATS) and the site of the chest tube, which are often located in the antero-lateral chest wall. Therefore, the SAPB can achieve effective analgesia in VATS. For example, 0.125% to 0.25% levobupivacaine (20-25 ml) is widely used for thoracic surgery, which can achieve effective analgesia and avoid adverse reactions. Moreover, it has advantages compared with thoracic segmental epidural block (TEA) and thoracic paravertebral block (TPVB), such as simple operation, increased safety, fewer complications, and hemodynamic stability. In addition, adequate analgesia is helpful for pulmonary function recovery and reduces the incidence of PPCs. This article introduces the anatomical mechanism of the SAPB, diverse operation approaches, how to choose drugs and adjuvants, and the resulting impacted area range. It summarizes the advantages and disadvantages of the SAPB compared with other analgesic methods and posits that the SAPB is beneficial to the recovery of postoperative lung function, which provides more options for postoperative analgesia after VATS.

14.
Sci Rep ; 11(1): 18591, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545152

RESUMO

Environmental exposures interact with genetic factors has been thought to influence susceptibility of systemic lupus erythematosus (SLE) development. To evaluate the effects of environmental exposures on SLE, we conducted a population-based cohort study across Jiangsu Province, China, to examine the associations between the living environment including air and water pollution, population density, economic income level, etc. and the prevalence and mortality of hospitalized SLE (h-SLE) patients. A total of 2231 h-SLE patients were retrieved from a longitudinal SLE database collected by the Jiangsu Lupus Collaborative Group from 1999 to 2009. The results showed that: It existed regional differences on the prevalence of h-SLE patients in 96 administrative districts; The distribution of NO2 air concentration monitored by atmospheric remote sensors showed that three of the ultra-high-prevalence districts were located in the concentrated chemical industry emission area; h-SLE patient prevalence was positively correlated with the excessive levels of nitrogen in drinking water; The positive ratio of pericarditis and proteinuria was positively correlated with the prevalence of h-SLE patients and pollution not only induced a high h-SLE patient prevalence but also a higher mortality rate, which might be attributed to NOx pollution in the air and drinking water. In summary, our data suggested that NOx in air and drinking water may be one of the important predispositions of SLE, especially for patients with renal involvement.


Assuntos
Poluição do Ar/efeitos adversos , Água Potável , Exposição Ambiental/efeitos adversos , Lúpus Eritematoso Sistêmico/epidemiologia , Poluição da Água/efeitos adversos , Adulto , China/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Lúpus Eritematoso Sistêmico/etiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
15.
Med Image Anal ; 74: 102207, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34487982

RESUMO

The assessment of myocardial perfusion has become increasingly important in the early diagnosis of coronary artery disease. Currently, the process of perfusion assessment is time-consuming and subjective. Although automated methods by threshold processing have been proposed, they cannot obtain an accurate perfusion assessment. Thus, there is a great clinical demand to obtain a rapid and accurate assessment of myocardial perfusion through a standard procedure using an automated algorithm. In this work, we present a spatio-temporal multi-task network cascade (ST-MNC) to provide an accurate and robust assessment of myocardial perfusion. The proposed network captures patch-based spatio-temporal representations for each pixel through a spatio-temporal encoder-decoder network. Then the multi-task network cascade uses spatio-temporal representations as shared features to predict various perfusion parameters and myocardial ischemic regions. Extensive experiments on CT images of 232 subjects demonstrate ST-MNC could produce a good approximation for perfusion parameters and an accurate classification for ischemic regions. These results show that our proposed method can provide a fast and accurate assessment of myocardial perfusion.

16.
BMC Endocr Disord ; 21(1): 154, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344344

RESUMO

BACKGROUND: Autoimmune polyendocrine syndrome type 1 (APS-1) is a rare monogenic inherited disease caused by mutations of the autoimmune regulator gene (AIRE). The three major components of this syndrome are chronic mucocutaneous candidiasis, hypoparathyroidism and adrenocortical insufficiency. CASE PRESENTATION: We report a 20-year-old male who was clinically diagnosed with APS-1 at the age of 15. He was admitted to our department this time for suffering from polyuria and polydipsia for 6 months and was finally diagnosed with diabetes insipidus. Whole-exome sequencing (WES) revealed a novel compound heterozygous mutation of the AIRE gene -the c.239 T > G (p.Val80Gly) variant on one allele and the copy number variant (CNV) of 21q22.3(chr21:45,670,150-45,706,528)*1 on the other. CONCLUSIONS: This case suggests that diabetes insipidus is a rare component of APS-1 and expands the variety of mutations on AIRE gene.

17.
Stem Cell Res Ther ; 12(1): 452, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380561

RESUMO

Mitophagy is a specific autophagic phenomenon in which damaged or redundant mitochondria are selectively cleared by autophagic lysosomes. A decrease in mitophagy can accelerate the aging process. Mitophagy is related to health and longevity and is the key to protecting stem cells from metabolic stress damage. Mitophagy decreases the metabolic level of stem cells by clearing active mitochondria, so mitophagy is becoming increasingly necessary to maintain the regenerative capacity of old stem cells. Stem cell senescence is the core problem of tissue aging, and tissue aging occurs not only in stem cells but also in transport amplifying cell chambers and the stem cell environment. The loss of the autophagic ability of stem cells can cause the accumulation of mitochondria and the activation of the metabolic state as well as damage the self-renewal ability and regeneration potential of stem cells. However, the claim remains controversial. Mitophagy is an important survival strategy against nutrient deficiency and starvation, and mitochondrial function and integrity may affect the viability, proliferation and differentiation potential, and longevity of normal stem cells. Mitophagy can affect the health and longevity of the human body, so the number of studies in this field has increased, but the mechanism by which mitophagy participates in stem cell development is still not fully understood. This review describes the potential significance of mitophagy in stem cell developmental processes, such as self-renewal, differentiation and aging. Through this work, we discovered the role and mechanism of mitophagy in different types of stem cells, identified novel targets for killing cancer stem cells and curing cancer, and provided new insights for future research in this field.


Assuntos
Mitocôndrias , Mitofagia , Autofagia , Humanos , Lisossomos/metabolismo , Células-Tronco/metabolismo
18.
World J Stem Cells ; 13(7): 737-752, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34367475

RESUMO

The mitochondrial unfolded protein response (UPRmt) is an evolutionarily conserved adaptive mechanism for improving cell survival under mitochondrial stress. Under physiological and pathological conditions, the UPRmt is the key to maintaining intracellular homeostasis and proteostasis. Important roles of the UPRmt have been demonstrated in a variety of cell types and in cell development, metabolism, and immune processes. UPRmt dysfunction leads to a variety of pathologies, including cancer, inflammation, neurodegenerative disease, metabolic disease, and immune disease. Stem cells have a special ability to self-renew and differentiate into a variety of somatic cells and have been shown to exist in a variety of tissues. These cells are involved in development, tissue renewal, and some disease processes. Although the roles and regulatory mechanisms of the UPRmt in somatic cells have been widely reported, the roles of the UPRmt in stem cells are not fully understood. The roles and functions of the UPRmt depend on stem cell type. Therefore, this paper summarizes the potential significance of the UPRmt in embryonic stem cells, tissue stem cells, tumor stem cells, and induced pluripotent stem cells. The purpose of this review is to provide new insights into stem cell differentiation and tumor pathogenesis.

19.
ACS Nano ; 15(9): 15114-15122, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34427090

RESUMO

Chiral growth and chirality transfer associated with plasmonic nanostructures have rejuvenated the field of chirality. As the precise regioselective growth of inorganic crystals into chiral shapes at the nanoscale is extremely challenging, "bottom-up" synthesis of intrinsically chiral nanoparticles with structural stability is obviously attractive and important. With the thiolated bimolecular cosurfactants, we demonstrated a chemical strategy for the synthesis of intrinsically helical plasmonic nanorods (HPNRs) with strong and tailorable plasmonic circular dichroism (PCD) responses, deriving from the zwitterionic interactions between the -NH3+ and -COO- groups of the cysteine molecules (Cys). The influence of structural parameters of HPNRs on PCD responses was analyzed systematically by theoretical simulations. Among the different structural parameters, the pitch depth was found to have the greatest impact on the PCD signals, in agreement with the experimental results. Moreover, the obtained HPNRs with the strong, tunable, and stable chiroptical properties were found to be able to induce circularly polarized luminescence of achiral luminophores. Due to the generality of this effect, this chiral plasmonic nanostructure may have great potential for use in the fields of chiral sensors, chiral catalysis, and displays.


Assuntos
Luminescência , Nanotubos
20.
Sci Total Environ ; 799: 149256, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34358740

RESUMO

Lakes and vegetation are important components of the hydro-ecological environment and sensitive indicators of anthropogenic climate change and human activities. For the first time, the lake area, vegetation cover change (obtained from Landsat satellite images), terrestrial water storage (TWS; estimated from the gravity recovery and climate experiment), and hydrochemistry, stable isotopes of different waterbodies were combined to analyze the long-term evolution and controlling factors of lake area and vegetation cover in the Nenjiang River basin, China. Between 1985 and 1999, the lake area experienced natural shrinkage due to climatic and hydrological changes, whereas artificial shrinkage related to increased human activities dominated during 2000-2019. The normalized difference vegetation index (NDVI) increased during 1988-1999 and was affected by hydrometeorological factors in the same year and lake area in the previous year. The rate of increase in the NDVI accelerated during 2000-2012 owing to the impact of human activities which is reflected by GDP, and the related artificial shrinkage of the lake area. The main hydrochemical type of lake water changed from Ca-HCO3 before 2000, which was similar to that of river water, to Na-HCO3 after 2000, which was the main hydrochemical type of groundwater. In addition, most of the lake water and groundwater samples were rich in H2SiO3, and a strong correlation between the TWS and lake area for the period 2003-2019 indicated that lake water was strongly affected by groundwater, which was related to deep circulation. Therefore, the decreased river water recharge owing to human activities made groundwater contribute more to lake water. This study can substantially improve the decision-making support for environmental protection and water resource management in ecologically diverse areas, specifically in arid and semi-arid areas.


Assuntos
Água Subterrânea , Rios , China , Monitoramento Ambiental , Humanos , Hidrologia , Lagos
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