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[Objective] Simulating the change of runoff and sediment changes in the watershed under the influence of land use and climate in the future is conducive to making suitable management plans. [Methods] Based on land use and meteorological data, combined with CMIP6 climate model data, PLUS model and SWAT model, the temporal and spatial changes of land use and runoff and sediment under different climate scenarios in 2030 were quantitatively simulated. [Results] (1) The SWAT model exhibited good accuracy in monthly scale in simulation of Minjiang River Basin, in which the R² and NSE (Nash-Sutcliffe Efficiency) ranged from 0.80 to 0.95 and 0.75 to 0.91, respectively. The R² and NSE ranged from 0.75 to 0.98 and 0.64 to 0.94 respectively. (2) Using the land use data of 2020 to evaluate the accuracy of the PLUS model, the Kappa coefficient was 0.77, and the simulated construction land and cultivated land in the Minjiang River Basin in 2030 would increase by 325.64 km² and 1 157.51 km², respectively. (3) Under the SSP2-4.5 and SSP5-8.5 scenarios, the average precipitation in 2025-2035 would increase by 0.15% and 2.18%, and the average annual temperature would increase by 0.23 and 0.62 °C, respectively. (4) In the low carbon and high carbon scenarios, only land use change led to an increase of 0.08% and 0.07% in annual mean runoff, and an increase f 0.24% and decreased of 0.05% in annual mean sediment transport, respectively, compared with the baseline period. Compared with the baseline period, the mean annual runoff decreased by 4.76 % and 4.11%, and the mean annual sediment transport increased by 18.12% and 0.13%, respectively. The combined effects of land use and climate resulted in a decrease of 4.57% and 3.93% in annual average runoff and an increase of 8.28% and 0.33% in annual average sediment transport compared with the base period, respectively. (5) Under the scenario of future climate and land use comprehensive change, the areas with higher and larger increase in surface runoff and sediment yield were concentrated in the northwestern of the basin centered on Shaowu City in Nanping and the southwest of the basin centered on Jiangle County in Sanming. [Conclusion] These research results provide some reference for the reasonable development and construction of Minjiang River basin in the future. [ABSTRACT FROM AUTHOR]

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The Minjiang River is an important first-level tributary of the Yangtze River. Understanding the driving factors of water quality variations in the Minjiang River is crucial for future policy planning of watershed ecology protection of the Yangtze River. The water quality of the Minjiang River is impacted by both meteorological factors and anthropogenic factors. By using wavelet analysis, machine learning, and Shapley analysis approaches, the impacts of meteorological factors and anthropogenic factors on the permanganate index (CODMn) and ammonia nitrogen (NH3-N) concentrations at the outlet of the Minjiang River Basin were quantified. The observed CODMn and NH3-N concentration data in the Minjiang River from 2016 to 2020 were decomposed into long-term trend signals and periodic signals. The long-term trends in water qualities showed that anthropogenic factors were the major driving factors, accounting for 98.38% of the impact on CODMn concentrations and 98.18% of the impact on NH3-N concentrations. The periodic fluctuations in water qualities in the Minjiang River Basin were mainly controlled by meteorological factors, with an impact of 68.89% on CODMn concentrations and 63.94% on NH3-N concentrations. Compared to anthropogenic factors, meteorological factors have a greater impact on water quality in the Minjiang River Basin during both the high-temperature and rainy seasons from July to September and during the winter from December to February. The separate quantification of impacts of driving factors on the varying water quality signals contributed to the originality in this work, providing more intuitive insights for the assessment of the influences of policies and the climate change on the water quality. [ABSTRACT FROM AUTHOR]

Urbanization has rapidly increased, leading to a wide range of significant disruptions to the global ecosystem. Road construction has emerged as the primary catalyst for such ecological degradation. As a result, it is imperative to develop efficient technological approaches for quantifying and tracking alterations in the ecological environment. Additionally, it is crucial to delve deeper into the spatial correlation between the quality of the ecosystem and the urban road network. This is of crucial importance in promoting sustainable development within the region. In this study, the research area selected was the Minjiang River Basin (MRB). We made optimal use of the Google Earth Engine (GEE) cloud platform to create a long-term series of remote sensing ecological index (RSEI) data in order to assess the quality of the ecological environment in the area. Additionally, we integrated digital elevation data (DEM) and OpenStreetMap (OSM) road network data to investigate the response mechanisms of RSEI with regard to elevation, slope, and the road network. The findings were as follows: (1) There were two distinct phases observed in the average value of RSEI: a slow-rising phase (2000–2010) with a growth rate of 1.09% and a rapidly rising phase (2010–2020) with a growth rate of 5.36%; the overall 20-year variation range fell between 0.575 and 0.808. (2) During the period of 2000 to 2010, approximately 41.6% of the area exhibited enhanced ecological quality, whereas 17.9% experienced degradation. Subsequently, from 2010 to 2020, the proportion of the region with improved ecological quality rose to 54.0%, while the percentage of degraded areas declined to 3.8%. (3) With increasing elevation and slope, the average value of RSEI initially rose and then declined. Specifically, the regions with the highest ecological quality were found in the areas with elevations ranging from 1200 to 1500 m and slopes ranging from 40 to 50°. In contrast, areas with an elevation below 300 meters or a slope of less than 10° had the poorest ecological quality. (4) The RSEI values exhibited a rapid ascent within the 1200 m buffer along the road network, while beyond this threshold, the increase in RSEI values became more subdued. (5) The bivariate analysis found a negative correlation between road network kernel density estimation (KDE) and RSEI, which grew stronger with larger scales. Spatial distribution patterns primarily comprised High–Low and Low–High clusters, in addition to non-significant clusters. The southeastern region contained concentrated High–Low clusters which covered approximately 10% of the study area, while Low–High clusters accounted for around 20% and were predominantly found in the western region. Analyzing the annual changes from 2000 to 2020, the southeastern region experienced a decrease in the number of High–Low clusters and an increase in the number of High–High clusters, whereas the northwestern region showed a decline in the number of Low–High clusters and an increase in the number of non-significant clusters. This study addresses a research gap by investigating the spatial correlation between road distribution and RSEI, which is vital for comprehending the interplay between human activities and ecosystem services within the basin system. [ABSTRACT FROM AUTHOR]

Copyright of Ecological Science is the property of Ecological Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecological Science is the property of Ecological Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Monitoring vegetation growth and exploring the driving force behind it is very important for the study of global climate change and ecological environmental protection. Based on Normalized Difference Vegetation Index (NDVI) data from Moderate-Resolution Imaging Spectroradiometer (MODIS), meteorological and nighttime lights data from 2001 to 2020, this study uses the Theil–Sen slope test, Mann–Kendall significance test, Rescaled Range Analysis and partial correlation analysis to investigate the evolution of NDVI in the Minjiang River Basin, China, from three aspects: the spatial-temporal variation characteristics and future trend prediction of NDVI, the variation of climate and human activities in the basin, and the influences of different driving forces on NDVI. The results show that the average NDVI in the growing season was 0.60 in the Minjiang River Basin in the past twenty years, with a growth rate of 0.002/a. The area with high NDVI growth accounts for 66.02%, mainly distributed in the southeast, the central and the northern low-altitude areas of the basin. Combined with the Hurst index, the NDVI in the Minjiang River Basin exhibits an anti-sustainable tendency, with 63.22% of the area changing from improvement to degradation in the future. Meanwhile, the spatial differentiation of NDVI in the Minjiang River Basin is mainly affected by topography and climate factors, followed by human activities. This study not only provides scientific guidelines for the vegetation restoration, soil and water conservation and sustainable development of the Minjiang River Basin, but also provides a scientific basis for making informed decisions on ecological protection under the impacts of climate change and human activities. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Disasters is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of South Architecture / Nanfang Jianzhu is the property of South Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pearl River is the property of Pearl River Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tibetans are one of the oldest ethnic groups in China and South Asia. Based on the analysis of 1,059 Tibetans in the Minjiang River basin at an altitude of 500–4,001 m, we found that the dominant phyla of the Tibetan population were Bacteroidota and Firmicutes , and the main genera were Prevotella and Bacteroides , which were mostly in consistent with other nationalities. We further evaluated in total 115 parameters of seven categories, and results showed that altitude was the most important factor affecting the variation in the microbial community. In the process of emigration from high altitudes to the plain, the gut microbial composition of late emigrants was similar to that of plateau aborigines. In addition, regarding immigration from low altitude to high altitude, the microbial community became more similar to that of high altitude population with the increase of immigration time. Changes in these microbes are related to the metabolism, disease incidence and cell functions of the Tibetan population. The results of other two cohorts (AGP and Z208) also showed the impact of altitude on the microbial community. Our study demonstrated that altitude of habitation is an important factor affecting the enterotype of the microflora in the Tibetan population and the study also provided a basis to explore the interaction of impact parameters with gut microbiome for host health and diseases. [ABSTRACT FROM AUTHOR]

Evapotranspiration is one of the critical processes in the terrestrial hydrological cycle, and the assessment of evapotranspiration is essential for understanding the regional hydrological cycle. In this study, the Minjiang River Basin, a typical watershed in the humid subtropical climate zone, is selected as the study region. The Penman-Monteith equation and the dual crop coefficient method are used to calculate the actual evapotranspiration (ETa) at seven meteorological stations within the study basin. Meanwhile, the applicability of the Global Land Data Assimilation System-Noah (GLDAS-Noah) ETa data in the Minjiang River Basin is evaluated based on stations P-M equation results, then to analyze the changes of the ETa in the Minjiang River Basin from 2000 to 2019. The results show that the GLDAS-Noah ETa data are well applicable in the Minjiang River Basin (R2 > 0.9 and NSE > 0.8). The ETa in the basin shows an increasing trend since 2000, and the increasing rate is 3.60 mm·yr−1 (p < 0.01). The seasonal variation results show that ETa tends to increase in winter and spring, with increasing rates of 1.10 mm·yr−1 (p < 0.01) and 2.60 mm·yr−1 (p < 0.01), respectively, while the ETa did not change significantly in summer and autumn. Annual air temperature has the largest effect on annual ETa (59.6%), followed by precipitation at 33.9%. ETa increased in spring was mainly influenced by increasing temperatures (89.4%) in the Minjiang River Basin from 2000 to 2019. The research results are of great benefit to further improve the understanding of ETa variations in the basin under global warming. [ABSTRACT FROM AUTHOR]

Dual factors of climate and human on the hydrological process are reflected not only in changes in the spatiotemporal distribution of water resource amounts but also in the various characteristics of river flow regimes. Isolating and quantifying their contributions to these hydrological alterations helps us to comprehensively understand the response mechanism and patterns of hydrological process to the two kinds of factors. Here we develop a general framework using hydrological model and 33 indicators to describe hydrological process and quantify the impact from climate and human. And we select the Upper Minjiang River (UMR) as a case to explore its feasibility. The results indicate that our approach successfully recognizes the characteristics of river flow regimes in different scenarios and quantitatively separates the climate and human contributions to multi-dimensional hydrological alterations. Among these indicators, 26 of 33 indicators decrease over the past half-century (1961–2012) in the UMR, with change rates ranging from 1.3% to 33.2%, and the human impacts are the dominant factor affecting hydrological processes, with an average relative contribution rate of 58.6%. Climate change causes an increase in most indicators, with an average relative contribution rate of 41.4%. Specifically, changes in precipitation and reservoir operation may play a considerable role in inducing these alterations. The findings in this study help us better understand the response mechanism of hydrological process under changing environment and is conducive to climate change adaptation, water resource planning and ecological construction. [ABSTRACT FROM AUTHOR]

Soil erosion is one of the main environmental problems in the world, and also an important branch of natural environment protection. Taking Minjiang River Basin as the research area, based on the supervised classification of land use status map, the comprehensive soil erosion modulus map was generated by referring to the soil erosion evaluation index and the revised soil loss equation (RUSLE). The results showed that the Minjiang River Basin is dominated by mild eroded area and middle eroded area, accounting for 41.50% and 54.81% of the total area respectively. High eroded area accounted for only 3.69%, mainly in the north and west, and there was no extremely sensitive area. From the perspective of land use types, the construction land and water body are mainly slightly sensitive areas, and forest land, garden land and cultivated land are mainly mild or middle sensitive areas, while the unused lands are shown as middle sensitive areas or highly sensitive areas. Through the discussion of the sensitivity evaluation of soil erosion in Minjiang River Basin, it can provide some references for the relevant departments to the soil and water conservation work in Minjiang River Basin. [ABSTRACT FROM AUTHOR]

An increase in extreme precipitation events due to future climate change will have a decisive influence on the formation of debris flows in earthquake-stricken areas. This paper aimed to describe the possible impacts of future climate change on debris flow hazards in the Upper Minjiang River basin in Northwest Sichuan of China, which was severely affected by the 2008 Wenchuan earthquake. The study area was divided into 1285 catchments, which were used as the basic assessment units for debris flow hazards. Based on the current understanding of the causes of debris flows, a binary logistic regression model was used to screen key factors based on local geologic, geomorphologic, soil, vegetation, and meteorological and climatic conditions. We used the weighted summation method to obtain a composite index for debris flow hazards, based on two weight allocation methods: Relative Degree Analysis and rough set theory. Our results showed that the assessment model using the rough set theory resulted in better accuracy. According to the bias corrected and downscaled daily climate model data, future annual precipitation (2030-2059) in the study area are expected to decrease, with an increasing number of heavy rainfall events. Under future climate change, areas with a high-level of debris flow hazard will be even more dangerous, and 5.9% more of the study area was categorized as having a high-level hazard. Future climate change will cause an increase in debris flow hazard levels for 128 catchments, accounting for 10.5% of the total area. In the coming few decades, attention should be paid not only to traditional areas with high-level of debris flow hazards, but also to those areas with an increased hazard level to improve their resilience to debris flow disasters. [ABSTRACT FROM AUTHOR]

Knowledge of vegetation distribution patterns is very important. Their relationships with topography and climate were explored through a geographically weighted regression (GWR) framework in a subtropical mountainous and hilly region, Minjiang River Basin of Fujian in China. The HJ-1 satellite image acquired on December 9, 2010 was utilized and NDVI index was calculated representing the range of vegetation greenness. Proper analysis units were achieved through segregation based on small sub-basins and altitudinal bands. Results indicated that the GWR model was more powerful than ordinary linear least square (OLS) regression in interpreting vegetation-environmental relationship, indicated by higher adjusted R2 and lower Akaike information criterion values. On one side, the OLS analysis revealed dominant positive influence from parameters of elevation and slope on vegetation distribution. On the other side, GWR analysis indicated that spatially, the parameters of topography had a very complex relationship with the vegetation distribution, as results of the various combinations of environmental factors, vegetation composition and also anthropogenic impact. The influences of elevation and slope generally decreased, from strongly positive to nearly zero, with increasing altitude and slope. Specially, most rapid changes of coefficients between NDVI and elevation or slope were observed in relatively flat and low-lying areas. This paper confirmed that the non-stationary analysis through the framework of GWR could lead to a better understanding of vegetation distribution in subtropical mountainous and hilly region. It was hoped that the proposed scale selection method combined with GWR framework would provide some guidelines on dealing with both spatial (horizontal) and altitudinal (vertical) non-stationarity in the dataset, and it could easily be applied in characterizing vegetation distribution patterns in other mountainous and hilly river basins and related research. [ABSTRACT FROM AUTHOR]