Responses of CO and CH in the alpine wetlands of the Tibetan Plateau to warming and nitrogen and phosphorus additions.

Wetland ecosystems store large amounts of carbon, and CO and CH fluxes from this ecosystem receive the double impact of climate change and human activities. Nonetheless, research on how multi-gradient warming and nitrogen and phosphorus additions affect these wetland greenhouse gas emissions is still limited, particularly in alpine wetland ecosystems. Therefore, we conducted a field experiment on the Tibetan Plateau wetlands, investigating the effects of warming and nitrogen and phosphorus additions on the CO and CH fluxes in alpine wetlands.

Global evapotranspiration from high-elevation mountains has decreased significantly at a rate of 3.923 %/a over the last 22 years.

Clarifying the responses of human activities and climate change to the water cycle under variable environments is crucial for accurately assessing regional water balance. An analysis of the changes in actual evapotranspiration and its driving factors was conducted in the global high-elevation mountains during the period from 2001 to 2022. Utilizing 18 formulas for calculating evapotranspiration, which are based on comprehensive, temperature, radiation, and mass transfer, and then simulated the variations in reference evapotranspiration.

Atmospheric precipitation chemistry and environmental significance in major anthropogenic regions globally.

In order to investigate the spatiotemporal distribution and influencing factors of global precipitation chemistry, we conducted a comprehensive analysis using multiple data sources, revealing the impact of human activities on the natural environment. The results indicate a decreasing trend in global precipitation acidity over the past 20 years. The distribution of global precipitation is influenced by both natural and anthropogenic factors.

The effect of freeze-thaw action on the dynamic change of supra-permafrost water sources: A stable isotope perspective.

Due to the continuous degradation (gradual thawing) of permafrost, supra-permafrost water has become an important component of runoff that occurs in cold regions. However, current research has only focused on the amount of water provided by permafrost, and little has been reported regarding the source and formation mechanisms of supra-permafrost water. Due to the difficulty of observation and sampling in cold regions and insufficient data accumulation, model simulations face various difficulties in regard to solving problems related to hydrological processes.

Vegetation restoration strategies based on plant water use patterns.

The study on the water source of plants in alpine mountainous is of great significance to optimize the allocation and management of water resources, and can also provide important reference for ecological restoration and protection. However, the controls of water sources for different plants in alpine mountainous region remain poorly understood. Based on the advantages of stable isotope tracer and Bayesian (MixSIAR) model, the water source of plants in Qilian Mountains was quantitatively analyzed.

Sand fixation and human activities on the Qinghai-Tibet Plateau for ecological conservation and sustainable development.

The sand fixation ecosystem services and human activities on the Qinghai-Tibet Plateau (QTP) play a crucial role in local sustainable development and ecosystem health, with significant implications for surrounding regions and the global ecological environment. We employed an improved integrated wind erosion modeling system (IWEMS) model for the QTP to simulate sand fixation quantities under the unique low temperature and low pressure conditions prevalent on the plateau. Using the human footprint index (HFI), the intensity of human activities on the plateau was quantified.

Particularity of hydrological processes under heavy ablation based on environmental isotopes in transition zones between endorheic and exorheic basins.

Drastic changes in the cryosphere have a significant impact on the quantity and formation process of water resources in the Qilian Mountains. The present study focused on quantitative evaluation of runoff components and runoff formation processes during strong ablation periods (August), in 2018, 2020, and 2021, in the transition zone between endorheic and exorheic basins in China, based on 1906 stable isotope samples. The results revealed that as the altitude decreased, the contribution of glacier and snow meltwater and permafrost water to runoff decreased, whereas that of the precipitation increased.

Precipitation changes and its interaction with terrestrial water storage determine water yield variability in the world's water towers.

Previous studies have quantified the contributions of climate factors, vegetation, and terrestrial water storage change, and their interaction effects on hydrological process variation within the Budyko framework; however, further decomposition of the contributions of water storage change has not been systematically investigated. Therefore, focusing on the 76 water tower units of the world, the annual water yield variance was first examined, followed by the contributions of changes in climate, water storage change, and vegetation, as well as their interaction effects on water yield variance; finally, the contribution of water storage change on water yield variance was further decomposed into the effect of changes in groundwater, snow water, and soil water. The results showed that large variability exists in the annual water yield with standard deviations ranging from to 10-368 mm in water towers globally.

[Spatial Distribution Characteristics and Influencing Factors of Soil Organic Carbon Density in Yellow River Basin Based on MGWR Model].

As the largest terrestrial carbon pool, the spatial distribution characteristics and influencing factors of soil organic carbon have important implications for global carbon cycle processes. Soil organic carbon density (SOCD) and influencing factors were predicted in the Yellow River basin using a mixed geographically weighted regression (MGWR) model based on soil organic carbon density data and environmental factors. The results showed that:① the SOCD ranged from 0-14.

Autotrophic denitrification using Fe(II) as an electron donor: A novel prospective denitrification process.

As a newly identified nitrogen loss pathway, the nitrate-dependent ferrous oxidation (NDFO) process is emerging as a research hotspot in the field of low carbon to nitrogen ratio (C/N) wastewater treatment. This review article provides an overview of the NDFO process and summarizes the functional microorganisms associated with NDFO from different perspectives. The potential mechanisms by which external factors such as influent pH, influent Fe(II)/N (mol), organic carbon, and chelating agents affect NDFO performance are also thoroughly discussed.

A review of isotope ecohydrology in the cold regions of Western China.

The mountainous alpine area in western China is an Asian water tower and is an important ecological barrier area. Based on the previous research results, this study sorted out and summarized the isotopic ecohydrology of the alpine mountains in the western China and found that the local meteoric water line (LMWL) in the west of the alpine mountains is δD = 7.44δO + 5.

Environmental significance of atmospheric nitrogen deposition in the transition zone between the Tibetan Plateau and arid region.

The ecological effect of atmospheric N deposition has become a hot research point along with intensive human activities and global climatic change. As the transition zone between the Tibetan Plateau and the arid region, the Qilian Mountains are important ecological barriers and source regions of inland rivers in northwest China. However, the quantification of N deposition in the transition zone between the Tibetan Plateau (TP) and the arid region remains unclear, primarily due to the lack of in situ measurements.

Hydrochemical patterns indicating hydrological processes with the background of changing climatic and environmental conditions in China: a review.

In the background of global climate and environmental change, the hydrochemical characteristics of water bodies present significant instability to all regions, including humid, arid, and alpine ones. There are two main reasons for this: (1) climate change has altered the temporal and spatial distribution of precipitation, and climate warming intensified the mutual transformation of water bodies. The temperature in China increased by 0.

Environmental effect and spatiotemporal pattern of stable isotopes in precipitation on the transition zone between the Tibetan Plateau and arid region.

In the transition zone between the Tibetan Plateau and the arid region of northwestern China, the spatiotemporal patterns and environmental controls of stable isotopes in precipitation remain unclear. A network of 19 sampling stations was established across the Qilian Mountains to observe stable isotopes in precipitation, and 1310 precipitation event-scale samples were collected. The local meteoric water line (LMWL) was obtained and expressed as δD = 7.

An ecological footprint approach for cropland use sustainability based on multi-objective optimization modelling.

Croplands are heterogeneous in productivity and their sustainable use holds a prominent place in supporting a virtual society-economy-ecology-environment circle. This study developed a model for the evaluation of cropland use sustainability by integrating the revised ecological footprint model with multi-objective optimization. The model enabled to gain insights into changes of the supply-demand balance of cropland use ecologically from a planning perspective, and also enables policy makers to determine the optimal patterns of cropland use in order to reconcile contradictions between multiple dimensions in agroecosystems, such as resource utilization, economy, society, and environment.

Transformation mechanism of ions on different waters in alpine region.

The study investigates transformation mechanism of ions on different waters in Alpine region through analyzed the hydrochemical characteristics of the major ions of precipitation, glacier and snow meltwater, supra-permafrost water and river water in permafrost regions in the Tibetan Plateau under climate warming. The results showed that, The relation between recharge and discharge was the major ways for ionic transformation of each water body. Precipitation and glacier and snow meltwater are the main input sources for ionic transformation, and river water is the final output source.

The sources of supra-permafrost water and its hydrological effect based on stable isotopes in the third pole region.

The sources of supra-permafrost water and its hydrological effects were studied, based on the presence of stable isotopes in 562 samples collected in different ablation periods from the source regions of the Yangtze River. The δO (δD and d-excess) values for the initial ablation, ablation, and end ablation periods were -10.18‰ (-71.

[Characteristics of Stable Isotopes and Analysis of Water Vapor Sources of Precipitation at the Northern Slope of the Qilian Mountains].

This study is based on precipitation samples from eight sites at the northern slope of the Qilian Mountains, combined with meteorological factors over the same period. Precipitation isotope characteristics, influence factors and the vapor sources of precipitation were analyzed, and the results show that:① The stable isotopes of precipitation in the study area show obvious seasonal changes, which are characterized by enrichment in the summer half-year and depletion in the winter half-year. The spatial precipitation O value shows a significant downward trend with increasing altitude, and the altitude effect of the annual precipitation O is -0.

Response mode of hydrochemical types of river water to altitude gradient in alpine regions.

The study investigates the hydrochemical type and characteristics of river water in permafrost regions in the Tibetan Plateau by analyzing 532 samples collected from the source region of the Yangtze River. The hydrochemical type of the river water was Cl-Na-SO, and its hydrochemical characteristics were primarily influenced by the soil sources, though the influence of the sea sources and anthropogenic factors could not be ignored. Significant negative correlations were found between temperature and NO, SO, Mg, Ca, and between precipitation, relative humidity, and SO and Mg in the river water.

Tracing geochemical pollutants in stream water and soil from mining activity in an alpine catchment.

This research developed a method of tracing major water chemical parameters (WCP) and soil heavy metals (HM) to identify the processes of mining pollution in topographically complex landscapes. Ninety-nine spatially distributed water samples were collected to characterise the hydrochemical characteristics of an alpine river in north-west China. Sixty river WCP and fifty-six soil HM samples from areas near mining sites were then used to analyse the mining pollution process.

[Space-time Characteristics and Environmental Significance of Stable Isotopes in Precipitation at an Arid Inland River Basin].

This study was based on one complete hydrological year sampling of precipitation and meteorological data of the Shiyang River Basin in the Wuwei Station (1531 m a.s.l.

Environment significance and hydrochemical characteristics of supra-permafrost water in the source region of the Yangtze River.

This paper analyzed the environment significance and hydrochemical characteristics of the main ions on the supra-permafrost water from the view of space-time and different ablations. The study is conducted through collected 330 samples from June to September in 2016 and 2017 in the Source Region of the Yangtze River (SRYR). The results showed the pattern of ionic dominance based on mean value was following as: Cl > Na > SO > Ca > Mg > K > NO > NO > NH > F > Li.

Climate background, relative rate, and runoff effect of multiphase water transformation in Qilian Mountains, the third pole region.

Multiphase water transformation has great effects on alpine hydrology, but these effects remain unclear in the third pole region. Taking the Qilian Mountains as an example, the climate background and relative rates of multiphase water transformation were analyzed, and the runoff effect was evaluated based on long-term field observations. There are three climatic aspects driving multiphase water transformation, including lengthening ablation period, accelerative warming after 1990, and larger warming in the cryosphere belt than in the vegetation belt.

[Space-Time Characteristics and Environmental Significance of the Stable Isotopes in Precipitation in the Gulang River Basin].

Based on the precipitation samples and meteorological data simultaneously collected during individual precipitation events at the Gulang (2085 m a.s.l.