The suitability of isotopic methods in identifying water sources of a shallow-rooted herbaceous plant in a desert steppe.

Isotopic methodologies have gained prominence in investigating the composition of plant water sources; however, concerns regarding their suitability and reliability in diverse environments have emerged in recent years. This study presents a comparative analysis of root, soil, and liquid water (precipitation, dew, and groundwater) samples obtained from a desert steppe using isotope ratio infrared spectrometry (IRIS) and isotope ratio mass spectrometry (IRMS). The objective was to evaluate the applicability of these techniques in discerning the water sources of Stipa breviflora, a shallow-rooted herbaceous plant species.

Effects of drought stress on water content and biomass distribution in summer maize( L.).

The resource allocation of different component organs of crops under drought stress is a strategy for the coordinated growth of crops, which also reflects the adaptability of crops to drought condition. In this study, maize variety namely 'Denghai 618', under the ventilation shed, two treatment groups of light drought (LD) and moderate drought (MD), and the same rehydration after drought are set, as well as the normal water supply for control in shed (CS). The drought experiment was conducted in the jointing-tasseling stage in 2021.

Drought-flood abrupt alteration events over China.

Drought-flood abrupt alternation (DFAA) is characterized by a period of persistent drought followed by sudden heavy precipitation at a certain level, with impacts on ecosystems and socioeconomic environment. At present, previous studies have mainly focuses on the monthly scale and regional scale. However, this study proposed a multi-indicator daily-scale method for identifying the DFAA occurrence, and explored the DFAA events over China from 1961 to 2018.

The persistent impact of drought stress on the resilience of summer maize.

Crop resilience refers to the adaptive ability of crops to resist drought at a certain level. Currently, most of the research focuses on the changes in root or photosynthesis traits of crops after drought and rehydration. Still, the persistence effect (drought period (T2) - rehydration period (T3) - harvest period (T4)) of drought stress on crops and quantitative estimation of resilience is still unclear.

Construction of root tip density function and root water uptake characteristics in alpine meadows.

Accurate calculation of root water uptake (RWU) is the key to improving vegetation water use efficiency and identifying water cycle evolution patterns, and root tips play an important role in RWU. However, most of the current RWU models in the alpine meadow are calculated based on the root length density (RLD) function. In this study, a large number of roots, soil hydraulic conductivity, and physicochemical property indices were obtained by continuous field prototype observation experiments for up to 2 years.

A data set of distributed global population and water withdrawal from 1960 to 2020.

Population and water withdrawal data sets are currently faced with difficulties in collecting, processing and verifying multi-source time series, and the spatial distribution characteristics of long series are also relatively lacking. Time series is the basic guarantee for the accuracy of data sets, and the production of long series spatial distribution is a realistic requirement to expand the application scope of data sets. Through the time-consuming and laborious basic processing work, this research focuses on the population and water intake time series, and interpolates and extends them to specific land uses to ensure the accuracy of the time series and the demand of spatially distributed data sets.

Underestimated permafrost degradation: Improving the TTOP model based on soil thermal conductivity.

Under the continuing influence of global warming, resolving the inconsistency of permafrost degradation rates and quantifying the spatial distribution characteristics are critical for high-altitude water cycle processes. The dynamics of permafrost degradation are mainly manifested in soil temperature, which can be measured with high accuracy and high temporal resolution. This study considered the influence of soil thermal conductivity (K) by periodic land surface temperature (LST), improved the static output of the temperature at the top of permafrost (TTOP) model, and verified the reliability of the TTOP model improvement by the Kappa coefficient.

Spatiotemporal characteristics of surface water resources in the Tibetan plateau: Based on the produce water coefficient method considering snowmelt.

The Tibetan Plateau (TP), with its widely distributed cryosphere elements and the source of 12 major rivers, is a strategic area for Asian water resource generation, storage, and migration. Because of the unique surface water resources (SWR) characteristics, multi-phase and multiple sources, the hydrological process here is extremely complex. Coupled with the lack of measured data, the SWR in the TP has not been quantified refinedly.

Variation trends and attribution analysis of lakes in the Qiangtang Plateau, the Endorheic Basin of the Tibetan Plateau.

The Tibetan Plateau (TP) is the area with most high-altitude lakes in the world, of which most are in the Qiangtang Plateau (QP), the endorheic basin of the TP. Since the 1990s, abundant studies have reported the accelerated expansion of lakes in the QP. However, the dominant factors affecting lakes expansion or shrinkage are still controversial.

Responses of Phosphate-Solubilizing Microorganisms Mediated Phosphorus Cycling to Drought-Flood Abrupt Alternation in Summer Maize Field Soil.

Soil microbial communities are essential to phosphorus (P) cycling, especially in the process of insoluble phosphorus solubilization for plant P uptake. Phosphate-solubilizing microorganisms (PSM) are the dominant driving forces. The PSM mediated soil P cycling is easily affected by water condition changes due to extreme hydrological events.

Regulation of heavy metals accumulated by Acorus calamus L. in constructed wetland through different nitrogen forms.

Improving accumulation of heavy metals (HMs) by plants is an important pathway for constructed wetland (CW) to alleviate the environmental risks caused by their release. This study aims to regulate HMs (Cr, Ni, Cu, Zn, and Cd) accumulated by Acorus calamus L. in the sandy substrate CW with different nitrogen forms, including ammonia (NH), nitrate (NO‾), and NH/NO‾ (1:1) in synthetic tailwaters.

Anthropogenic Effects on Hydrogen and Oxygen Isotopes of River Water in Cities.

Stable hydrogen and oxygen isotopes are important indicators for studying water cycles. The isotopes are not only affected by climate, but are also disturbed by human activities. Urban construction has changed the natural attributes and underlying surface characteristics of river basins, thus affecting the isotopic composition of river water.

A data set of global river networks and corresponding water resources zones divisions.

As basic data, the river networks and water resources zones (WRZ) are critical for planning, utilization, development, conservation and management of water resources. Currently, the river network and WRZ of world are most obtained based on digital elevation model data automatically, which are not accuracy enough, especially in plains. In addition, the WRZ code is inconsistent with the river network, hindering the efficiency of data in hydrology and water resources research.

Author Correction: A data set of inland lake catchment boundaries for the Qiangtang Plateau.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Wetlands of International Importance: Status, Threats, and Future Protection.

The 2303 Wetlands of International Importance distribute unevenly in different continents. Europe owns the largest number of sites, while Africa has the largest area of sites. More than half of the sites are affected by three or four impact factors (55%).

A data set of inland lake catchment boundaries for the Qiangtang Plateau.

A catchment is the basic unit for studying hydrologic cycle processes and associated climate change impacts. Accurate catchment delineation is essential in the field of hydrology, environment, and meteorology. Traditionally, catchment delineation is most easily carried out where the outflow area can be easily determined because of a well-defined outlet.

Changes in Major Global River Discharges Directed into the Ocean.

Under the influence of global climate change, the discharges of major global rivers directed into the ocean have undergone significant changes. To study the trends and causes in discharge variation, we selected 40 large rivers and analyzed their annual discharges near their estuaries from 1960 to 2010. The method of runoff variation attribution analysis based on the Budyko hypothesis for large-scale basins was developed, in which influencing factors of human activities and glacial melting factors were added to the formula.

Evolution of Drought⁻Flood Abrupt Alternation and Its Impacts on Surface Water Quality from 2020 to 2050 in the Luanhe River Basin.

It has become a hot issue to study extreme climate change and its impacts on water quality. In this context, this study explored the evolution characteristics of drought⁻flood abrupt alternation (DFAA) and its impacts on total nitrogen (TN) and total phosphorous (TP) pollution, from 2020 to 2050, in the Luanhe river basin (LRB), based on the predicted meteorological data of the representative concentration pathways (RCPs) climate scenarios and simulated surface water quality data of the Soil and Water Assessment Tool (SWAT) model. The results show that DFAA occurred more frequently in summer, with an increasing trend from northwest to southeast of the LRB, basically concentrated in the downstream plain area, and the irrigation area.

Bioelectricity generation from air-cathode microbial fuel cell connected to constructed wetland.

The aim of this study was to investigate the different performance of bioelectricity generation and wastewater treatment between constructed wetland (CW) respectively coupled with air-cathode microbial fuel cell (ACMFC) and microbial fuel cell (MFC) under a fed-batch mode. During a 75-day-operation, the voltage of CW-ACMFC and CW-MFC ranged from 0.36 to 0.

Bioenergy generation and degradation pathway of phenanthrene and anthracene in a constructed wetland-microbial fuel cell with an anode amended with nZVI.

The frequent occurrence of polycyclic aromatic hydrocarbons (PAHs) in aquatic environments is of great concern because of their teratogenicity, toxicity, carcinogenicity, and mutagenicity to plants, animals and human beings. In this study the bioelectricity generation, biodegradation, phytoextraction and substrate adsorption of phenanthrene and anthracene in a constructed wetland-microbial fuel cell (CW-MFC) were investigated with an anode electrode amended with or without biochar-nZVI. During a 182-day operation period, the average removal efficiency for phenanthrene and anthracene ranged from 88.

Variation of Hydrothermal Conditions under Climate Change in Naqu Prefecture, Tibet Plateau, China.

Analysis of the suitability of hydrothermal conditions for vegetation growth would benefit the ecological barrier construction, water resources protection and climate change adaptation. The suitability of hydrothermal conditions in Naqu Prefecture was studied based on the spatial displacement of 500 mm precipitation and 2000 °C accumulated temperature contours. Results showed that the 500 mm precipitation contour had a shifting trend toward the southwest, with a 3.

Evolution Characteristics of Surface Water Quality Due to Climate Change and LUCC under Scenario Simulations: A Case Study in the Luanhe River Basin.

It is of great significance to study the effects and mechanisms of the key driving forces of surface water quality deterioration-climate change and LUCC (land use and land cover change). The Luanhe River Basin (LRB) in north-eastern China was examined for qualitatively and quantitatively assessing the responses of total nitrogen (TN) and total phosphorus (TP) loads on different climate scenarios and LUCC scenarios. The results show that from 1963 to 2017, the TN and TP loads basically presented a negative correlation with the temperature change (except for winter), while showing a significant positive correlation with the precipitation change.