scholarly journals The impact of outgassing of CO2 and prior calcium precipitation to the isotope composition of calcite precipitated on stalagmites. Implications for reconstructing climate information from proxies

2021 ◽  
pp. 120676
Author(s):  
Wolfgang Dreybrodt ◽  
Jens Fohlmeister
Keyword(s):  
Isotope Composition ◽  
Climate Information ◽  
The Impact ◽  
Calcium Precipitation

The impact of temperature on the degree of structurization of water of different isotope composition

2017 ◽  
Vol 39 (4) ◽  
pp. 185-190
Author(s):  
V. V. Goncharuk ◽  
I. Yu. Romanyukina ◽  
M. D. Skil’skaya ◽  
A. I. Marynin ◽  
A. V. Syroeshkin ◽  
...  
Keyword(s):  
Isotope Composition ◽  
The Impact

Epithermal Fluorite Deposits in Transbaikalia (Geochemical Features, Sources of Matter and Fluids, and Genesis)

2021 ◽  
Vol 62 (4) ◽  
pp. 415-426
Author(s):  
E.I. Lastochkin ◽  
G.S. Ripp ◽  
D.S. Tsydenova ◽  
V.F. Posokhov ◽  
A.E. Murzintseva
Keyword(s):  
Meteoric Water ◽  
Isotope Composition ◽  
Spatial Proximity ◽  
Thermal Waters ◽  
Sr Isotope ◽  
Light Isotope ◽  
Geochemical Parameters ◽  
Nd Systems ◽  
Deep Source ◽  
The Impact

Abstract —We consider the isotope-geochemical features of epithermal fluorite deposits in Transbaikalia, including the REE compositions, Sr isotope ratios, Sm–Nd systems, and isotope compositions of oxygen, carbon, hydrogen, and sulfur. The 87Sr/86Sr ratios in fluorites are within 0.706–0.708, and the εNd values are negative. Oxygen in quartz, the main mineral of the deposits, has a light isotope composition (δ18O = –3.4 to +2.6‰), and the calculated isotope composition of oxygen in the fluid in equilibrium with quartz (δ18O = –9 to –16‰) indicates the presence of meteoric water. The latter is confirmed by analysis of the isotope compositions of oxygen and hydrogen in gas–liquid inclusions in fluorites from three deposits. These isotope compositions are due to recycling caused by the impact of shallow basic plutons. The isotope composition of sulfur indicates its deep source. During ascent, sulfur became enriched in its light isotope (δ34S = –1.8 to –7.7‰). We assess the association of fluorite ores with basaltoids widespread in the study area. The isotope and geochemical parameters suggest their spatial proximity. Probably, the basaltoids were responsible for the recycling of meteoric water. It is shown that the epithermal fluorite deposits formed by the same mechanism as fissure–vein thermal waters in western Transbaikalia.

NUKLEUS - User-relevant and applicable kilometer-scale climate information for Germany

2021 ◽  
Author(s):  
Kevin Sieck ◽  
Bente Tiedje ◽  
Hendrik Feldmann ◽  
Joaquim Pinto
Keyword(s):  
Climate Models ◽  
Local Scale ◽  
Easy Access ◽  
Climate Information ◽  
Post Processing ◽  
Last Mile ◽  
Wide Range ◽  
Impact Modelling ◽  
The Impact ◽  
Impact Models

<p>Given the current developments in climate science it becomes more a more feasible to provide climate information at the kilometer-scale from convection-permitting climate simulations. This progress will enable many users to directly feed high-resolution climate information into their impact-models for climate impact studies at the local scale. Examples include urban heat stress at street level or the design of drainage systems for future precipitation extremes. Within the RegIKlim (Regional information for action on climate change) consortium, the NUKLEUS (Actionable local climate information for Germany) project will not only provide climate information at the local scale, but also to co-develop interfaces between climate and impact models, in order to fulfil the needs of the impact modelling community as good as possible. Within the RegIKlim consortium, the impact modelling community is organised in six “model regions” across Germany, which cover a wide range of geographical and socio-economic conditions.</p><p>For the NUKLEUS project, the baseline will be the latest generation of EURO-CORDEX downscaled CMIP6 simulations, which will be further refined to roughly 3 km horizontal resolution and 30-year time-slices for Germany with convection-permitting climate models (ICON CLM, COSMO-CLM, REMO-NH) and statistical-dynamical downscaling approaches. A detailed analysis on the performance of the multi-model mini-ensemble is planned to assess the quality of the provided data. At the interface to the users, we will follow three different approaches to provide usable climate information at the kilometer-scale. One is to provide easy-access to data and post-processing opportunities using the FREVA system. FREVA offers various access-levels from shell to web-based, which serves different levels of user-expertise. In addition, it provides a transparent way of post-processing data by workflow sharing mechanisms. The second one is to develop appropriate additional downscaling methods for the “last mile” where needed. For this “last mile”, we will apply dynamical and statistical methods such as urban climate models and/or weather generators. With the third approach we explicitly aim at integrating a collected user-feedback into the regional modelling systems used within NUKLEUS. Specifically, we intend to identify and incorporate data processing that is best done during the simulation permanently into the models. Examples are wind speeds at rotor heights of windmills or high frequency precipitation sums. NUKLEUS is a contribution to the German research program RegIKlim funded by the Federal Ministry of Education and Research (BMBF).</p>

The impact of an inverse climate–isotope relationship in soil water on the oxygen‐isotope composition of Larix gmelinii in Siberia

2015 ◽  
Vol 209 (3) ◽  
pp. 955-964 ◽  
Author(s):  
Matthias Saurer ◽  
Alexander V. Kirdyanov ◽  
Anatoly S. Prokushkin ◽  
Katja T. Rinne ◽  
Rolf T. W. Siegwolf
Keyword(s):  
Oxygen Isotope ◽  
Soil Water ◽  
Isotope Composition ◽  
Oxygen Isotope Composition ◽  
Larix Gmelinii ◽  
The Impact

An igneous-textured clast in the Peace River meteorite: insights into accretion and metamorphism of asteroids in the early solar system

2013 ◽  
Vol 50 (1) ◽  
pp. 14-25 ◽  
Author(s):  
Christopher D.K. Herd ◽  
Jon M. Friedrich ◽  
Richard C. Greenwood ◽  
Ian A. Franchi
Keyword(s):  
Solar System ◽  
Isotope Composition ◽  
Parent Body ◽  
Early Solar System ◽  
Element Abundances ◽  
Fine Grained ◽  
Peace River ◽  
Petrology And Geochemistry ◽  
Mineral Compositions ◽  
The Impact

The mineralogy, petrology, and geochemistry of an igneous-textured clast in the Peace River L6 chondrite meteorite was examined to determine the roles of nebular processes, accretion, and parent-body metamorphism in its origin. The centimetre-scale clast is grey and fine grained and is in sharp contact with the host chondrite. Two sub-millimetre veins cut across both the clast and host, indicating that the clast formed prior to the impact (shock) event(s) that produced the numerous veins present in the Peace River meteorite. The clast and host are indistinguishable in terms of mineral compositions. In contrast, there are differences in modal mineralogy, texture, as well as trace element and oxygen isotope composition between the clast and host. These differences strongly suggest that the clast was formed by impact melting of LL-group chondritic material involving loss of Fe–FeS and phosphate components, followed by relatively rapid cooling and incorporation into the Peace River host meteorite. Subsequent metamorphism on the Peace River parent body caused recrystallization of the clast and homogenization of mineral compositions and thermally labile element abundances between the clast and host. Shock metamorphism, including formation of shock melt veins, occurred post-metamorphism, during fragmentation of the L chondrite parent body. The results suggest that the formation of the Peace River parent asteroid included the incorporation of material from other asteroids and that the pre-metamorphic protolith was a breccia. Accordingly, we propose that the Peace River meteorite be reclassified as a polymict breccia.

scholarly journals Isotopic composition of maize as related to N-fertilization and irrigation in the Mediterranean region

2011 ◽  
Vol 68 (2) ◽  
pp. 182-190 ◽  
Author(s):  
Berta Lasa ◽  
Iosu Irañeta ◽  
Julio Muro ◽  
Ignacio Irigoyen ◽  
Pedro María Aparicio Tejo
Keyword(s):  
Isotopic Composition ◽  
Zea Mays L ◽  
Isotope Composition ◽  
Application Rate ◽  
N Fertilization ◽  
Furrow Irrigation ◽  
N Leaching ◽  
C And N ◽  
Set Up ◽  
The Impact

Nitrate leaching as a result of excessive application of N-fertilizers and water use is a major problem of vulnerable regions. The farming of maize requires high N fertilization and water inputs in Spain. Isotopic techniques may provide information on the processes involved in the N and C cycles in farmed areas. The aim of this work was studying the impact of sprinkler and furrow irrigation and N input on maize (Zea mays L.) yields, and whether isotopic composition can be used as indicator of best farming practices. Trials were set up in Tudela (Spain) with three rates of N fertilization (0, 240 and 320 kg urea-N ha-1) and two irrigation systems (furrow and sprinkler). Yield, nitrogen content, irrigation parameters, N fate and C and N isotope composition were determined. The rate of N fertilization required to obtain the same yield is considerably higher under furrow irrigation, since the crop has less N at its disposal in furrow irrigation as a result of higher loss of nitrogen by NO3--N leaching and denitrification. A lower δ13C in plants under furrow irrigation was recorded.The δ15N value of plant increased with the application rate of N under furrow irrigation.

scholarly journals Issues in Climate Smart Agriculture in Southeastern Nigeria

2020 ◽  
pp. 190-200
Author(s):  
E. O. Okoro ◽  
V. U. Okwu- Delunzu ◽  
C. S. Ofordu
Keyword(s):  
Climate Change ◽  
Crop Production ◽  
Information Service ◽  
Climate Information ◽  
Southeastern Nigeria ◽  
Climate Services ◽  
Innovative Strategies ◽  
Climate Change And Variability ◽  
Negative Implication ◽  
The Impact

Farming is a prime livelihood activity of people of Southeast (SE) Nigeria. In the age of climate change, farmers have to cope with highly variable, short and unpredicted rainfall to sustain their enterprise. This study reviews the effects of climate change on agriculture production, identifies farmer's views on the impact of climate change on crop production in the southeast, reviews the adoption of CSA in Nigeria and identifies the importance of climate information service in agriculture in Southeast Nigeria. From the review, farmers within the SE are aware of climate change and they have adopted improved innovative strategies to adapt to the negative implication associated with climate change and variability but more awareness is needed in the area of climate information services (CIS) to assist them to cope better. Therefore, this study recommends the Participatory Integrated Climate Services for Agriculture (PICSA) approach to educate farmers more on how to manage their enterprise in the face of climate change and variability.

scholarly journals Comparative Performances of Beneficial Microorganisms on the Induction of Durum Wheat Tolerance to Fusarium Head Blight

2021 ◽  
Vol 9 (12) ◽  
pp. 2410
Author(s):  
Zayneb Kthiri ◽  
Maissa Ben Jabeur ◽  
Kalthoum Harbaoui ◽  
Chahine Karmous ◽  
Zoubeir Chamekh ◽  
...  
Keyword(s):  
Grain Yield ◽  
Durum Wheat ◽  
Fusarium Head Blight ◽  
Isotope Composition ◽  
Canopy Temperature ◽  
Seed Coating ◽  
Head Blight ◽  
C Metabolism ◽  
Carbon And Nitrogen Content ◽  
The Impact

Durum wheat production is seriously threatened by Fusarium head blight (FHB) attacks in Tunisia, and the seed coating by bio-agents is a great alternative for chemical disease control. This study focuses on evaluating, under field conditions, the effect of seed coating with Trichoderma harzianum, Meyerozyma guilliermondii and their combination on (i) FHB severity, durum wheat grain yield and TKW in three crop seasons, and (ii) on physiological parameters and the carbon and nitrogen content and isotope composition in leaves and grains of durum wheat. The results indicated that the treatments were effective in reducing FHB severity by 30 to 70% and increasing grain yield with an increased rate ranging from 25 to 68%, compared to the inoculated control. The impact of treatments on grain yield improvement was associated with higher NDVI and chlorophyll content and lower canopy temperature. Furthermore, the treatments mitigated the FHB adverse effects on N and C metabolism by resulting in a higher δ13Cgrain (13C/12Cgrain) and δ15Ngrain (15N/14Ngrain). Overall, the combination outperformed the other seed treatments by producing the highest grain yield and TKW. The high potency of seed coating with the combination suggests that the two microorganisms have synergetic or complementary impacts on wheat.

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