The time series of stable water isotope composition relative to IAEA-GNIP meteorological stations located in alpine zones are analyzed in order to study how the amplitude of the seasonal isotopic composition of precipitation (Aδ) varies along a vertical transect. A clear relationship between Aδ and local evaporation is obtained, with slopes of -0.87 ‰/100mm/yr and -7.3 ‰/100mm/yr for Aδ(18)O and Aδ(2)H, respectively. When all sampling points of the vertical transect receive the same moisture sources, then a linear relationship between Aδ and elevation is obtained, with vertical gradients of 0.16 ‰/100mm/yr and 1.46 ‰/100mm/yr forAδ(18)O and Aδ(2)H, respectively.
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http://dx.doi.org/10.1016/j.scitotenv.2015.12.034 | DOI Listing |
Physiol Plant
January 2025
Department of Radioecology, Institute for Environmental Sciences, Aomori, Japan.
The use of stored carbon is essential for new organ development in deciduous trees during early spring. However, the contribution of carbon to the development of new organs in early spring of subsequent years is not well understood. Using a C labelling approach, we investigated the reallocation of assimilated carbon into new aboveground organs on apple (Malus domestica) saplings in the following two years.
View Article and Find Full Text PDFFront Plant Sci
January 2025
College of Agriculture, Shihezi University, Shihezi, China.
Introduction: In order to elucidate the physiological mechanism of post-flowering assimilate transport regulating the formation of yields in arid regions and to provide technological support for further water-saving and high yields in the wheat region in Xinjiang, we conducted a study on the effects of different fertility periods and different degrees of drought and re-watering on the post-flowering dry matter accumulation and transport of spring wheat and the characteristics of grain filling.
Methods: In two spring wheat growing seasons in 2023 and 2024, a split-zone design was used, with the drought-sensitive variety Xinchun 22 (XC22) and drought-tolerant variety Xinchun 6 (XC6) as the main zones and a fully irrigated control during the reproductive period [CK, 75%~80% field capacity (FC)], with mild drought at the tillering stage (T1, 60%~65% FC), moderate drought at the tillering stage (T2, 45%~50% FC), mild drought at the jointing stage (J1, 60%~65% FC), and mild drought at the jointing stage (J2, 45%~50% FC) as the sub-zones.
Results: The dry matter accumulation of the aboveground parts of wheat (stem sheaths, leaves, and spikes), the transfer rate and contribution rate of nutrient organs, the maximum filling rate (V), and the mean filling rate (V) increased significantly after re-watering in the T1 treatment, and decreased with the deepening of the degree of water stress.
Nat Commun
January 2025
Department of Anthropology, University of Arkansas, Fayetteville, AR, USA.
The timing of the initial dispersal of hominins into Eurasia is unclear. Current evidence indicates hominins were present at Dmanisi, Georgia by 1.8 million years ago (Ma), but other ephemeral traces of hominins across Eurasia predate Dmanisi.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Department of Geology, Aligarh Muslim University, Aligarh, India.
Evolution of groundwater genesis in Central Ganga Plain (CGP) is scrutinized with due consideration of hydrochemical and hydrodynamic environment within Quaternary alluviums. Wide variation in hydrochemical facies in CGP indicates a dynamic hydro-geochemical environment influenced from the seasonal rainfall, return flows, canal seepages, and anthropogenic activities. The Ca-HCO facies retaining meteoric nature is characterized by shallow water levels, high recharge rate, high hydraulic conductivity, low salinity and trace elemental load.
View Article and Find Full Text PDFEnviron Res
January 2025
State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, National Hulunbuir Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address:
Increasing extreme precipitation and drought events along changes in their seasonal patterns due to climate change are expected to have profound consequences for carbon cycling. However, how these climate extremes impact ecosystem respiration (R) and whether these impacts differ between seasons remain unclear. Here, we reveal the responses of R and its components to extreme precipitation and drought in spring and summer by conducting a five-year manipulative experiment in a temperate meadow steppe.
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