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1.
Glob Chang Biol ; 30(4): e17267, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563471

RESUMEN

Lakes, as integral social-ecological systems, are hotspots for exploring climatic and anthropogenic impacts, with crucial pathways revealed by continuous sediment records. However, the response of multi-proxies in large shallow lakes to typical abrupt events and sustained drivers since the Anthropocene remains unclear. Here, we explored the driver-identification relationships between multi-proxy peaks and natural and anthropogenic events as well as the attribution of short-term perturbations and long-term pressures. To this end, sediment core records, socio-ecological data, and documented events from official records were integrated into a large shallow lake (Dongting Lake, China). Significant causal cascades and path effects (goodness-of-fit: 0.488; total effect: -1.10; p < .001) were observed among catchment environmental proxies, lake biogenic proxies, and mixed-source proxies. The peak-event identification rate (PEIR) and event-peak driving rate were proposed, and values of 28.57%-46.43% and 50%-81.25% were obtained, respectively. The incomplete accuracy of depicting event perturbations using sediment proxies was caused by various information filters both inside and outside the lake. PEIRs for compound events were 1.41 (±0.72) and 1.09 (±0.46) times greater than those for anthropogenic-dominated and natural-dominated events, respectively. Furthermore, socio-economic activity, hydrologic dynamics, land-use changes, and agriculture exerted significant and persistent pressures, cumulatively contributing 55.3%-80.9% to alterations in sediment proxies. Relatively synergistic or antagonistic trends in temporal contributions of these forces were observed after 2000, which were primarily attributed to the "Grain for Green" project and the Three Gorges Dam. This study represents one of the few investigations to distinguish the driver-response relationship of multiple proxies in large shallow lakes under typical event perturbations and long-term sustained pressures since the Anthropocene. The findings will help policymakers and managers address ecological perturbations triggered by climate change and human activities over long-term periods.


Asunto(s)
Sedimentos Geológicos , Lagos , Humanos , Ecosistema , China , Agricultura , Monitoreo del Ambiente
2.
Water Res ; 255: 121509, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38537491

RESUMEN

Interconnected river-lake systems record sedimentary organic carbon (OCsed) dynamics and watershed environmental changes, providing valuable information for global carbon budgets and watershed management. However, owing to the evolving river-lake interactions under global change, monitoring OCsed is difficult, thereby impeding the understanding of OCsed transport and fate. This study provided new insights into the dynamical mechanisms of OCsed in a typical river-lake system consisting of Dongting Lake and its seven inlet/outlet rivers (the three inlets of the Yangtze River and four tributaries) over the last century using stable isotope tracing and quantified the influences of climate change and human activities on OCsed. Results indicated that exogenous OC dominated the OCsed in the lake (58.2 %-89.0 %) and was lower in the west than in the east due to the differences in the material inputs and depositional conditions within the lake. Temporally, the distribution patterns of OCsed sources mainly responded to human activities in the basin rather than to climate change. Before 2005, the Yangtze River contributed the most OCsed (53.5 %-74.6 %), attributed to the high-intensity land use changes (path coefficient (r∂): 0.48, p-value < 0.01) and agriculture-industry activities (r∂: 0.44, p-value < 0.001) in the Yangtze River basin that increased soil erosion. After 2005, a large amount of Yangtze River OC was intercepted by the Three Gorges Dam, altering the OC exchange in the river-lake system and shifting OCsed dominance to the four tributaries (52.2 %-63.8 %). These findings highlight the active response of OCsed to the river-lake interaction evolution and anthropogenic control, providing critical information for regulating watershed management behavior under global change.

3.
Sci Total Environ ; 916: 170101, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38242474

RESUMEN

The presence of residual antibiotics in the environment is a prominent issue. Photodegradation behavior is an important way of antibiotics reduction, which is closely related to dissolved organic matter (DOM) in water. The review provides an overview of the latest advancements in the field. Classification, characterization of DOM, and the dominant mechanisms for antibiotic photodegradation were discussed. Furthermore, it summarized and compared the effects of DOM on different antibiotics photodegradation. Moreover, the review comprehensively considered the factors influencing the photodegradation of antibiotics in the aquatic environment, including the characteristics of light, temperature, dosage of DOM, concentration of antibiotics, solution pH, and the presence of coexisting ions. Finally, potential directions were proposed for the development of predictive models for the photodegradation of antibiotics. Based on the review of existing literature, this paper also considered several pathways for the future study of antibiotic photodegradation. This study allows for a better understanding of the DOM's environmental role and provides important new insights into the photochemical fate of antibiotics in the aquatic environment.


Asunto(s)
Antibacterianos , Contaminantes Químicos del Agua , Materia Orgánica Disuelta , Fotólisis , Contaminantes Químicos del Agua/química , Agua/química
4.
Environ Sci Pollut Res Int ; 31(4): 5655-5667, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38123779

RESUMEN

The combined role of ground cover management in controlling soil erosion and nutrient loss from new orchards is still less understood. In this study, four ground cover management practices, orchard with grass cover (OG), orchard with interplant cover (OI), orchard with straw cover (OS), and orchard with bare ground (OB), were designed to identify their impacts on soil erosion and associated carbon-nitrogen-phosphorus loss in new orchards by rainfall simulation tests with rainfall intensities of 60, 90, and 120 mm h-1 and 90 min rainfall duration. The results showed that OS had the lowest surface flow coefficient (6.6%) and highest subsurface flow coefficient (32.5%). The highest soil loss rate occurred in the OB plot (65.4 g m-2 min-1), and the lowest soil loss rate occurred in the OS plot (0.5 g m-2 min-1). OS plot showed better effectiveness in improving soil erosion. However, the increased infiltration capacity was facilitated in terms of causing non-point source pollution. The C-N-P ratios of surface flow in different cover measures (OB, OI, OG, and OS) were 1.4:1.2:0.9:1, 1.8:1.7:1.2:1, and 2.3:1.9:1.2:1, respectively. The ratios of sediment in different cover measures were 7.3:9:2.3:1, 2:1.5:1.2:1, and 1.2:1:0.8:0.7, respectively. Cover management plots play an active role in reducing nutrient loss in surface flow and sediment, but the increased infiltration in covered management plots is associated with the risk of groundwater contamination in subsurface flow. The C-N-P ratios of subsurface flow in OB and covered managed plots (OI, OG, and OS) were 1:3.3:1.6:2.7, 1:1.5:2.2:2.4 and 1:1.2:1.5:1.3, respectively. Therefore, when managing the phenomenon of soil erosion through ground cover measures, attention should also be focused on the function of cover measures in regulating non-point source pollution underground, such as subsurface flow. This research recommends a combination of cover management measures to further mitigate erosion and the risk of groundwater contamination.


Asunto(s)
Nitrógeno , Fósforo , Nitrógeno/análisis , Carbono , Suelo , Poaceae , Lluvia
5.
J Environ Manage ; 344: 118617, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37453298

RESUMEN

The abandonment of rice terraces in hilly agroecosystems in recent decades has caused substantial changes in microbial characteristics and their impact on microbial necromass carbon (MNC) and soil organic carbon (SOC). Nevertheless, the regulatory mechanisms and impact pathways of MNC remain unclear. Here, soil samples were collected from 0 to 120 cm soil profiles in rice terraces, dry land (DL), and forest land (FL) for analysis. After converting rice terraces to DL and FL, MNC decreased significantly by 31.12% and 38.33%, while SOC decreased significantly by 51.26% and 29.87% respectively. These reductions are due to the loss of terrace management practices and associated functions. There were no significant changes in bacterial necromass carbon (BNC), whereas fungal necromass carbon (FNC) experienced a significant decrease. As a result, the decline in SOC may be primarily attributed to the reduction in FNC. BNC and FNC were regulated by bacterial life history strategies and fungal biomass, respectively. However, bacterial copiotrophs experienced a significant reduction after rice terrace abandonment. The regulation of BNC may be influenced by other factors, potentially offsetting the negative impact of abandonment. Dissolved organic carbon and bulk density were the primary control factors for bacterial community composition and fungal biomass, respectively. Additionally, the impact of soil layers on the alterations in MNC and SOC was more significant compared to the abandonment of rice terraces. These findings indicate that short-term abandonment of rice terraces results in a decrease in SOC, potentially compromising the ecological service function of the hilly agroecosystems. In the face of rapid population growth and global warming, it is crucial to minimize terrace abandonment and enhance utilization rates. This approach will effectively support sustainable terrace management and ecological services.


Asunto(s)
Carbono , Oryza , Carbono/análisis , Suelo , Biomasa , Bosques , Bacterias , Microbiología del Suelo
6.
Environ Int ; 172: 107788, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36738584

RESUMEN

Sediment organic carbon (SOC) is a precious archive that synthesizes anthropogenic processes that remove geochemical fluxes from watersheds. However, the scarcity of inspection about the dynamic mechanisms of anthropogenic activities on SOC limits understanding into how key human factors drive carbon dynamics. Here, four typical basins with similar natural but significantly diverse human contexts (high-moderate-low disturbance: XJ-ZS and YJ-LS) were selected to reconstruct sedimentation rates (SR) and SOC dynamics nearly a century based on 200-cm corers. A partial least squares path model (PLS-PM) was used to establish successive (70 years) and multiple anthropogenic data (population, agriculture, land use, etc.) quantification methods for SOC. Intensified anthropogenic disturbances shifted all SR from pre-stable to post-1960s fluctuating increases (total coefficient: high: 0.63 < low: 0.47 < medium: 0.45). Although land use change was co-critical driver of SOC variations, their trend and extent differed under the dams and other disturbances (SOC mutated in high-moderate but stable in low). For high basin, land use changes increased (0.12) but dams reduced (-0.10) the downstream SOC. Furthermore, SOC mutation corresponded to soil erosion due to urbanization in both periods A and B. For moderate, SOC was reversed with the increase in afforestation and cropland (-0.19) due to the forest excitation effect and deep ploughing, which corresponded to the drought in phase B and the anthropogenic ecological project in A. For low, the increase in SOC corresponded to the Great Leap Forward deforestation in period B and the reed sweep in A, which suggested the minor land change substantially affected (0.16) SOC in fragile environments. Overall, SOC dynamics revealed that anthropogenic activities affected terrestrial and aquatic ecosystems for near the centenary, especially land use. This is constructive for agroforestry management and reservoir construction, consistent with expectations like upstream carbon sequestration and downstream carbon stabilization.


Asunto(s)
Ecosistema , Suelo , Humanos , Efectos Antropogénicos , Carbono/análisis , Agricultura , Secuestro de Carbono , China
7.
Water Res ; 233: 119779, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36848854

RESUMEN

Sediment organic carbon (SeOC) sources with rich information can be used as a "historical archive" reflecting anthropogenic activities in the catchment, which is crucial to carbon management in the watershed. Anthropogenic activities and hydrodynamic conditions significantly influence the river environment and are reflected by the SeOC sources. However, the key drivers of the SeOC source dynamics are ambiguous, which restricts the behavior of regulating the carbon output of the basin. In this study, sediment cores from the lower reach of an inland river were selected to quantify the SeOC sources based on a centennial scale. A partial least squares path model was used to establish the relationship between anthropogenic activities and hydrological conditions with the SeOC sources. Findings showed that the exogenous advantage of SeOC composition was gradually significant (early period: 54.3%; middle period: 81%; later period: 82%) from the bottom layer to the surface layer of the sediments in the lower reach of the Xiangjiang River. Factors related to anthropogenic activities controlled the external input of SeOC (δ13C: r∂ = -0.94, P < 0.001; δ15N: r∂ = -0.66, P < 0.001). Different anthropogenic activities performed different effects. Land use change aggravated soil erosion and brought more terrestrial organic carbon to the downstream. The variation of grassland carbon input was the most obvious (from 33.6% to 18.4%). In contrast, the reservoir construction intercepted upstream sediments, which might have been the main reason for the slow growth of terrestrial organic carbon input in the downstream in the later period. This study provides a specific grafting for the SeOC records - source changes - anthropogenic activities in the lower reach of the river, which provides scientific basis for watershed carbon management.


Asunto(s)
Efectos Antropogénicos , Carbono , Carbono/análisis , Sedimentos Geológicos , Monitoreo del Ambiente , Ríos
8.
Artículo en Inglés | MEDLINE | ID: mdl-36767471

RESUMEN

A deeper understanding of the rainfall-flow processes can improve the knowledge of the rain-driven erosional processes in coarse-textured agricultural soil. In this study, on the red soil slope farmland developed from weathered granite, a simulated rainfall experiment was conducted to study the characteristics of rainfall redistribution, the processes of surface-subsurface flow generation and prediction, and sediment production. Rainfalls with three intensities of 45, 90, and 135 mm h-1 with a duration of 90 min were applied to the weathered granite red soil with the slope gradient of 10°. Under 45 mm h-1 rainfall intensity, the output of rainwater was composed by subsurface flow and bottom penetration, accounting for 35.80% and 39.01% of total rainfall, respectively. When the rainfall intensities increased to 90 and 135 mm h-1, the surface flow became the main output of rainwater, accounting for 83.94% and 92.42%, respectively. Coarsened soil exhibited strong infiltration-promoting but poor water-storage capacities under light rainfalls. With an increased rainfall intensity, the surface flow coefficient increased from 19.87% to 92.42%, while the amount of subsurface flow and bottom penetration decreased by 1.3 and 6.2 L, respectively. For sediment production, the sediment concentration was raised from 1.39 to 7.70 g L-1, and D10, D50, and D90 increased by 1.50, 1.83, and 1.40 times, respectively. The content of coarse particles (>1 mm) in surface soil increased by 12%, while the content of fine particles (<0.5 mm) decreased by 9.6%. Under strong rainfalls, severe soil and water loss, coarsening soil surface, and large loss of fine particles became major problems. During rainfall, the subsurface flow and bottom penetration could be predicted well through quadratic equations of rainfall time, which transformed into time-dependent exponential functions after rainfall. The results provide a theoretical basis and data reference for soil erosion prevention and water management in coarse-textured agricultural lands.


Asunto(s)
Sedimentos Geológicos , Suelo , Movimientos del Agua , Lluvia , Agua , China
9.
Artículo en Inglés | MEDLINE | ID: mdl-36673938

RESUMEN

Fine particulate matter (PM2.5) pollution brings great negative impacts to human health and social development. From the perspective of heterogeneity and the combination of national and urban analysis, this study aims to investigate the variation patterns of PM2.5 pollution and its determinants, using geographically and temporally weighted regression (GTWR) in 273 Chinese cities from 2015 to 2019. A comprehensive analytical framework was established, composed of 14 determinants from multi-dimensions, including population, economic development, technology, and natural conditions. The results indicated that: (1) PM2.5 pollution was most severe in winter and the least severe in summer, while the monthly, daily, and hourly variations showed "U"-shaped, pulse-shaped and "W"-shaped patterns; (2) Coastal cities in southeast China have better air quality than other cities, and the interaction between determinants enhanced the spatial disequilibrium of PM2.5 pollution; (3) The determinants showed significant heterogeneity on PM2.5 pollution-specifically, population density, trade openness, the secondary industry, and invention patents exhibited the strongest positive impacts on PM2.5 pollution in the North China Plain. Relative humidity, precipitation and per capita GDP were more effective in improving atmospheric quality in cities with serious PM2.5 pollution. Altitude and the proportion of built-up areas showed strong effects in western China. These findings will be conductive to formulating targeted and differentiated prevention strategies for regional air pollution control.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Ciudades , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Contaminación del Aire/análisis , China
10.
J Environ Manage ; 329: 117064, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535145

RESUMEN

In recent decades, terraces abandonment has been prevalent in the hilly areas of China. Soil fungi play an important role in clarifying soil ecosystematic feedback after ancient rice terraces abandonment, but how their community composition and function shift remains unclear. Soil profiles of 0-120 cm were excavated in ancient rice terraces, dry land, and forest land (formed from ancient rice terraces abandonment), respectively. The 13C NMR and high-throughput sequencing were used to determine soil organic carbon chemical groups and fungal community, respectively, and FUNGuild was used to predict functional groups. The results showed that the soil fungal community changed from Ascomycota to Basidiomycota after ancient rice terraces abandonment. The trophic modes of dry land and forest land were transformed into pathotrophic fungi and symbiotrophic fungi, respectively. The number of nodes and edges of fungal co-occurrence networks increased by 83.8% and 644.1% in dry land, and 81.3% and 431.2% in forest land, respectively. Moreover, soil nutrients (especially DOC, TN, and TP) can more affected the variation of fungal community composition and function than soil organic carbon chemical groups. These findings indicate that soil fungal community shifts in different directions in response to ancient rice terraces abandonment, which is related to the adaptive strategies for environmental changes and may be more conducive to the acquisition and turnover of soil nutrients.


Asunto(s)
Micobioma , Oryza , Suelo/química , Carbono , Hongos , Nutrientes , China , Microbiología del Suelo
11.
Front Microbiol ; 13: 1007237, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36532439

RESUMEN

Microbial communities and functions play an important role in soil carbon and nitrogen transformations, and, in recent decades, the abandonment of terraces is prevalant in the hilly areas of China. However, it is unclear how soil carbon and nitrogen contents and prokaryotic communities changed as a result of the abandonment of ancient rice terraces. Soil profiles ranging from 0 to 120 cm were excavated on drylands, forestlands (both converted due to the abandonment of ancient rice terraces), and ancient rice terraces. The FAPROTAX database was used to predict soil prokaryotic functional groups. The results showed that soil organic carbon (SOC) and total nitrogen (TN) contents of abandoned ancient rice terraces in drylands (51.09 and 33.20%) and forestlands (31.76 and 16.59%) were significantly reduced. Soil prokaryotic diversity and community composition changed dramatically after the abandonment of terraces and were mainly affected by soil pH and ammoniacal nitrogen ( NH 4 + -N). Community composition was more similar in drylands and forestlands. Moreover, the abundance of transformation functional genes of carbon (57.01 and 50.80%) and nitrogen (15.25 and 22.36%) in bacterial communities was significantly reduced, and of carbon in the archaeal communities decreased sharply (28.10 and 46.50%), in drylands and forestlands. These findings indicate that short-term abandonment of ancient rice terraces reduces soil carbon and nitrogen contents, which may be closely related to the decline of prokaryotic functional groups. The prevalence of short-term abandonment of rice terraces in the hilly areas of China may pose adverse ecological risks.

12.
Molecules ; 27(23)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36500336

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease with limited therapeutic options. Pseudognaphalium affine (D. Don) Anderb. is a medicinal and edible plant used to treat cough, asthma, and COPD for a long time in folk medicine. The objective of this study is to evaluate the effect of Pseudognaphalium affine (D. Don) Anderb. extract (GAE) and investigate the possible underlying mechanism in vivo and in vitro. In vivo, the administration of GAE in a rat COPD model could significantly ameliorate lung damage and pulmonary function by inhibiting the production of pro-inflammatory cytokines. Western blot and real-time PCR results showed that GAE could suppress nuclear translocation of nuclear factor-kappa B (NF-κB), which indicated that GAE down-regulated the NF-κB pathway. Moreover, GAE protected against tumor necrosis factor (TNF)-α induced inflammatory response in BEAS-2B and inhibited the NF-κB pathway. All data suggested that GAE exhibited its anti-COPD effect by inhibiting pro-inflammatory cytokines, which may be associated with the inhibition of the NF-κB pathway.


Asunto(s)
Asteraceae , Enfermedad Pulmonar Obstructiva Crónica , Ratas , Animales , FN-kappa B/metabolismo , Transducción de Señal , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Pulmón , Factor de Necrosis Tumoral alfa/metabolismo , Citocinas/metabolismo , Asteraceae/metabolismo , Extractos Vegetales/uso terapéutico
13.
Environ Res ; 215(Pt 2): 114392, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36152885

RESUMEN

Total organic carbon (TOC) in lake sediments from upstream catchments is deposited and buried in substrate, recording historical environmental changes. However, the linkage among natural variability, anthropogenic activity, and TOC burial for has not yet been clarified. This study examined the lake sediments of five 200-cm-deep dated depositional cores in west Dongting lake, China to quantify the magnitude, allocation, and amplitude of TOC burial. 44.47-59.36% of TOC burial flux was buried at 100-200 cm, suggesting lake sediments at deep layers stored considerable carbon. TOC burial rate (BRTOC) decreased along the lake entrance to its body, which was explained by the geochemical differences. Since 1900, BRTOC presented an increasing with a 4-7 times uptrend, showing three sedimentary stages with the increased human disturbance, such as deforestation, hydroelectric facilities. Moreover, the coefficient of variation of BRTOC in the third stage was lower than that in the second stage for the implementation of watershed reforestation and reservoir construction. Our findings stressed that natural variations of lake sedimentation background induced the change of TOC burial among the depositional sites, and enhanced that anthropogenic perturbation drove its chronological increases. This research unveiled the linkage between TOC burial, natural variability, and human disturbance from the perspective of burial evolutions in a lacustrine sedimentary environment.


Asunto(s)
Lagos , Contaminantes Químicos del Agua , Carbono/análisis , China , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos , Ríos , Contaminantes Químicos del Agua/análisis
14.
Phytother Res ; 36(9): 3662-3671, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35766233

RESUMEN

Inflammatory bowel disease (IBD) is a non-specific chronic intestinal inflammatory disease, often presenting with abdominal pain, diarrhea, bloody stool, anorexia, and body loss. It is difficult to cure completely and a promising treatment is urgently needed. Natural compounds can offer promising chemical agents for treatment of diseases. Polydatin is a natural ingredient extracted from the dried rhizome of Polygonum cuspidatum, which has anti-inflammatory, anti-tumor, and dementia protection activities. The purpose of this study was to evaluate the therapeutic effect of polydatin on IBD and explore its possible mechanism. We found that polydatin could effectively suppress the differentiation of Th17 cells in vitro, but had no effect on the differentiation of Treg cells. Polydatin significantly alleviated colitis induced by dextran sulfate sodium (DSS) and 2, 4, 6-trinitrobenzenesulfonic acid (TNBS) in mice, and dramatically decreased the proportion of Th17 cells in spleen and mesenteric lymph nodes. Mechanism investigations revealed that polydatin specifically inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation by directly binding to STAT3, leading to Th17 cell reduction and thereby alleviating colitis. These findings provide novel insights into the anti-colitis effect of polydatin, which may be a promising drug candidate for the treatment of IBD.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Animales , Diferenciación Celular , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colon , Sulfato de Dextran , Modelos Animales de Enfermedad , Glucósidos , Enfermedades Inflamatorias del Intestino/patología , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción STAT3/metabolismo , Estilbenos , Linfocitos T Reguladores/metabolismo , Células Th17 , Ácido Trinitrobencenosulfónico/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-35627349

RESUMEN

Due to high-intensity human disturbance and rapid climate change, optimizing the spatial pattern of land use has become a pivotal path to restoring ecosystem functions and realizing the sustainable development of human-land relationships. This review uses the literature analysis method combined with CiteSpace to determine current research progress and frontiers, challenges, and directions for further improvement in this field. The main conclusions include the following: (a) research on the optimization of spatial pattern of land use has transformed from pattern description orientation to sustainable development orientation to ecological restoration orientation. Its research paradigm has changed from pattern to function to well-being; (b) the research frontier mainly includes spatial pattern of land use that takes into account the unity of spatial structure and functional attributes, the ecological mechanism and feedback effect of change in spatial pattern of land, the theoretical framework and model construction of land use simulation and prediction based on multiple disciplines and fields, and the adaptive management of sustainable land use in the context of climate change; (c) based on current research challenges, we integrate the research on landscape ecology and ecosystem service flows to develop an "element sets-network structure-system functions-human well-being" conceptual model. We also propose the strengthening of future research on theoretical innovation, spatiotemporal mechanism selection, causal emergence mechanism, the transformation threshold, and uncertainty. We provide innovative ideas for achieving sustainable management of land systems and territorial spatial planning with the aim of improving the adaptability of land use spatial optimization. This is expected to strengthen the ability of land systems to cope with ecological security and climate risks.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Cambio Climático , Humanos , Modelos Teóricos , Desarrollo Sostenible
16.
Molecules ; 28(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36615213

RESUMEN

Huangqin is the dried root of Scutellaria baicalensis Georgi, which has been widely utilized for heat-clearing (Qingre) and dewetting (Zaoshi), heat-killed (Xiehuo) and detoxifying (Jiedu) in the concept of Traditional Chinese Medicine and is used for treating inflammation and cancer in clinical formulas. Neobaicalein (NEO) is of flavonoid isolated from Huangqin and has been reported to possess prominent anti-inflammatory effects in published work. Th17/Treg balance shift to Th17 cells is an essential reason for autoimmune inflammatory diseases. However, the role NEO plays in Th17 and Treg and the underlying mechanism has not been elucidated yet. Network pharmacology-based study revealed that NEO predominantly regulated IL-17 signaling pathway. Moreover, our result shown that NEO (3-30 µmol/L) down-regulated Th17 differentiation and cellular supernatant and intracellular IL-17A level and tumor necrosis factor α production in a concentration-dependent manner. The further mechanism research revealed that NEO also specifically inhibited phosphorylation of STAT3(Tyr725) and STAT4 (Y693) without influence on activation of STAT5 and STAT6 in splenocytes. Immunofluorescence results illuminated that NEO effectively blocked STAT3 translocated into nucleus. Interestingly, NEO at appreciated dose could only inhibit Th17 cell differentiation and have no effect on Treg differentiation. The present study revealed that NEO effectively inhibited Th17 cell differentiation through specifically blocking the activation of STAT3 signaling without inactivation of STAT5 and STAT6. Additional inhibitory effect on activation of STAT4 by NEO also suggested the potential for antagonism against Th1 differentiation. All work suggested that NEO may be a potential candidate for immunoregulation and treating autoimmune inflammatory diseases through inhibiting immune cell viability and T cell differentiation.


Asunto(s)
Enfermedades Autoinmunes , Células Th17 , Humanos , Factor de Transcripción STAT5/metabolismo , Linfocitos T Reguladores , Diferenciación Celular , Transducción de Señal , Factor de Transcripción STAT3/metabolismo , Enfermedades Autoinmunes/metabolismo
17.
Toxins (Basel) ; 13(12)2021 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-34941719

RESUMEN

This study was conducted to compare the potential ameliorative effects between probiotic Bacillus subtilis and biodegradable Bacillus subtilis on zearalenone (ZEN) toxicosis in gilts. Thirty-six Landrace×Yorkshire gilts (average BW = 64 kg) were randomly divided into four groups: (1) Normal control diet group (NC) fed the basal diet containing few ZEN (17.5 µg/kg); (2) ZEN contaminated group (ZC) fed the contaminated diet containing an exceeded limit dose of ZEN (about 300 µg/kg); (3) Probiotic agent group (PB) fed the ZC diet with added 5 × 109 CFU/kg of probiotic Bacillus subtilis ANSB010; (4) Biodegradable agent group (DA) fed the ZC diet with added 5 × 109 CFU/kg of biodegradable Bacillus subtilis ANSB01G. Results showed that Bacillus subtilis ANSB010 and ANSB01G isolated from broiler intestinal chyme had similar inhibitory activities against common pathogenic bacteria. In addition, the feed conversion ratio and the vulva size in DA group were significantly lower than ZC group (p < 0.05). The levels of IgG, IgM, IL-2 and TNFα in the ZC group were significantly higher than PB and DA groups (p < 0.05). The levels of estradiol and prolactin in the ZC group was significantly higher than those of the NC and DA groups (p < 0.05). Additionally, the residual ZEN in the feces of the ZC and PB groups were higher than those of the NC and DA groups (p < 0.05). In summary, the ZEN-contaminated diet had a damaging impact on growth performance, plasma immune function and hormone secretion of gilts. Although probiotic and biodegradable Bacillus subtilis have similar antimicrobial capacities, only biodegradable Bacillus subtilis could eliminate these negative effects through its biodegradable property to ZEN.


Asunto(s)
Alimentación Animal/toxicidad , Bacillus subtilis , Toxinas Bacterianas/farmacología , Toxinas Bacterianas/uso terapéutico , Probióticos/uso terapéutico , Sustancias Protectoras/uso terapéutico , Zearalenona/toxicidad , Animales , Femenino , Probióticos/farmacología , Porcinos
18.
J Environ Manage ; 299: 113660, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34481371

RESUMEN

A clear quantification and spatial mapping between supply and demand of water provision service in relation to climate change and urban expansion can provide some guidance to water resources management. Nevertheless, so far, most researches ignored the dynamic changes and influences of supply-demand coupling correlations. In this study, water yield and water demand were quantified and mapped in the Xiangjiang River Basin (XRB) from 2000 to 2018 by using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) and water-demand models, then the spatial distribution characteristics and their matching relationship were identified by using the univariate local autocorrelation analysis and the common logarithm of water supply-demand ratio (WSDR). With that, the contributions of climate and socio-economic factors to the above-mentioned changes were explored by using geographic detector. Results showed that the annual water yield increased by 20.20% in 2000-2015 and decreased by 33.92% in 2015-2018 affected by precipitation and land use changes; Changsha-Zhuzhou- Xiangtan urban agglomeration (CZX) and Southwest of Yongzhou were the high value areas of water yield (>338 m3/hm2). Due to the urban expansion, the water demand increased by 40.50% from 2000 to 2005 and decreased by 36.39% after 2005; From 2000 to 2018, high value areas of water demand (>53566 m3/hm2) mainly appeared in midstream and downstream with high urbanization level, dense population and developed industry. Under the joint action of precipitation (prep) and urban expansion, the overall state of supply and demand in the upper reaches was surplus, and more than 90% of the regions in midstream and downstream were at the middle and high level of supply shortage, especially in Hengyang and Chenzhou. Consequently, the increasing needs of human beings should be emphasized from the overall perspective of the basin, the growth rate of construction land and the necessary green infrastructure should be controlled reasonably and configured for achieving win-win goals of coordinating environmental protection and urban development.


Asunto(s)
Ecosistema , Agua , China , Conservación de los Recursos Naturales , Humanos , Ríos , Urbanización , Abastecimiento de Agua
19.
Artículo en Inglés | MEDLINE | ID: mdl-34335849

RESUMEN

Neuroinflammation plays a crucial part in the commencement and advancement of ischemic stroke. Gualou Guizhi granule (GLGZG) is known to well exhibit neuroprotective effect, but it is not known whether GLGZG can regulate the inflammatory process at the cellular level in BV2 microglia cells and protect against microglia-mediated neurotoxicity in neurons. Herein, we aimed to investigate the anti-inflammatory effects of GLGZG on BV2 microglia cells and protection against microglia-mediated neurotoxicity in neurons. Methods. The cell model of neuroinflammation was constructed by lipopolysaccharide (LPS) to observe the effect of GLGZG in the presence or absence of GLGZG. The production of nitric oxide (NO), inflammatory mediators, was detected. Moreover, potential mechanisms associated with the anti-inflammatory effect, such as inhibition of microglial activation and nuclear factor kappa B (NF-κB), were also investigated. In addition, to prove whether GLGZG protects against microglia-mediated neurotoxicity, neuronal HT-22 cells were cultured in the conditioned medium. And cell survivability and neuronal apoptosis of HT-22 were evaluated. Results. It was found that a main regulator of inflammation, NO, is suppressed by GLGZG in BV2 microglial cells. Moreover, GLGZG dose dependently decreased the mRNA and protein levels of inducible NO synthase (iNOS) in LPS-stimulated BV2 cells. Additionally, GLGZG inhibited the expression and secretion of proinflammatory cytokines in BV2 microglial cells. Also, GLGZG inhibited LPS-activated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in BV2 microglial cells at the intracellular level. GLGZG significantly affected Akt phosphorylation: phosphorylated forms of Akt increased. To check whether GLGZG protects against microglia-mediated neurotoxicity, neuronal HT-22 cells were incubated in the conditioned medium. GLGZG showed a neuroprotective effect by promoting cell survivability and suppressing neuronal apoptosis. Conclusions. GLGZG exerted its potential effects on suppressing inflammatory responses in LPS-induced BV2 cells by regulating NF-κB and Akt pathways. In addition, GLGZG could protect against microglia-mediated neurotoxicity in HT-22.

20.
J Anim Sci Biotechnol ; 12(1): 80, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34253252

RESUMEN

BACKGROUND: The present study aimed at evaluating the effect of vitamin K (VK) supplementation on bone health of laying hens challenged by Salmonella Enteritidis. METHODS: A total of 80 32-week-old double negative salmonella-free brown-egg laying hens were randomly assigned to 4 treatments with 20 replicates each (1 bird per replicate) according to a 2 × 2 factorial design with 2 dietary VK supplementation levels [0 mg/kg (VK0) vs 2 mg/kg VK (VK2) and 2 challenge treatments [Salmonella Enteritidis (SE) vs physiological saline solution (PS)]. During the last 3 days of week 43 of age, birds of both VK treatments were either orally challenged with 1.0 mL suspension of 109 cfu/mL S. Enteritidis daily or received the same volume of PS. RESULTS: The laying rate, daily egg mass, tibia strength, CT, cOC and cOC/(cOC + ucOC) of VK2 treatment increased (P < 0.05) in contrast to VK0, however, the medullary area and ucOC of VK2 treatment decreased (P < 0.05) in contrast to VK0. Mortality, medullary area, serum Ca content of SE treatments increased (P < 0.05) in contrast to PS treatments. In both SE treatments, the decrease (P < 0.05) in birds' tibia strength was associated with higher (P < 0.05) Ca levels in serum. There is an interaction (P < 0.05) between SE challenge and VK levels with regard to tibia strength and serum Ca levels. At week 42, serum CT was positively correlated with cOC (R = 0.99, P = 0.009); at week 44, tibia strength was positively correlated with BMD (R = 0.95, P = 0.045), but negatively correlated with medullary area (R = - 0.98, P = 0.018). CONCLUSIONS: VK (2 mg/kg) supplementation to diets of laying hens can enhance bone strength under challenge situations with Salmonella Enteritidis. Medullary area has proven to be a sensitive biomarker for bone calcium loss caused by SE infection.

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