scholarly journals Sulfate deprivation triggers high methane production in a disturbed and rewetted coastal peatland

2018 ◽  
Author(s):  
Franziska Koebsch ◽  
Matthias Winkel ◽  
Susanne Liebner ◽  
Bo Liu ◽  
Julia Westphal ◽  
...  
Keyword(s):  
Coastal Wetlands ◽  
Methane Emissions ◽  
Dissimilatory Sulfate Reduction ◽  
Climate Effect ◽  
Efficient Measure ◽  
Electrical Conductivities ◽  
Agricultural Use ◽  
Favorable Conditions ◽  
Isotope Partitioning ◽  
Underlying Processes

Abstract. In natural coastal wetlands, high supplies of marine sulfate suppress methanogenesis. Coastal wetlands are, however, often subject to disturbance by dyking and drainage for agricultural use and it has been shown that they can turn to potent methane sources when rewetted for remediation, suggesting that the sulfate-related methane suppressing mechanisms were suspended by the preceding land use measures. Here, we unravel the hydrological relocation and biogeochemical S and C transformation processes that induced high methane emissions in a disturbed and rewetted peatland despite former brackish impact. The underlying processes were investigated along a transect of increasing distance to the coastline using a combination of concentration patterns, stable isotope partitioning and analysis of the microbial community structure. We found that dyking and freshwater rewetting caused a distinct freshening and an efficient depletion of the brackish sulfate reservoir by dissimilatory sulfate reduction (DSR). Despite some legacy effects of brackish impact expressed as high amounts of sedimentary S and elevated electrical conductivities, contemporary metabolic processes operated mainly under sulfate-limited conditions. This opened up favorable conditions for the establishment of a prospering methanogenic community in the top 30–40 cm of peat, the structure and physiology of which resembles those of terrestrial organic-rich environments. Locally, high amounts of sulfate persisted in deeper peat layers through the suppression of DSR, probably by competitive electron acceptors of terrestrial origin, for example Fe(III), but did not interfere with high methane emissions on ecosystem scale. Our results indicate that the climate effect of disturbed and remediated coastal wetlands cannot simply be derived by analogy with their natural counterparts. From a greenhouse gas perspective, the re-exposure of dyked wetlands to natural coastal dynamics would literally open up the floodgates for a replenishment of the marine sulfate pool and constitute an efficient measure to reduce methane emissions.

scholarly journals Sulfate deprivation triggers high methane production in a disturbed and rewetted coastal peatland

2019 ◽  
Vol 16 (9) ◽  
pp. 1937-1953 ◽  
Author(s):  
Franziska Koebsch ◽  
Matthias Winkel ◽  
Susanne Liebner ◽  
Bo Liu ◽  
Julia Westphal ◽  
...  
Keyword(s):  
Coastal Wetlands ◽  
Methane Emissions ◽  
Dissimilatory Sulfate Reduction ◽  
Climate Effect ◽  
Efficient Measure ◽  
Electrical Conductivities ◽  
Agricultural Use ◽  
Favorable Conditions ◽  
Isotope Partitioning ◽  
Underlying Processes

Abstract. In natural coastal wetlands, high supplies of marine sulfate suppress methanogenesis. Coastal wetlands are, however, often subject to disturbance by diking and drainage for agricultural use and can turn to potent methane sources when rewetted for remediation. This suggests that preceding land use measures can suspend the sulfate-related methane suppressing mechanisms. Here, we unravel the hydrological relocation and biogeochemical S and C transformation processes that induced high methane emissions in a disturbed and rewetted peatland despite former brackish impact. The underlying processes were investigated along a transect of increasing distance to the coastline using a combination of concentration patterns, stable isotope partitioning, and analysis of the microbial community structure. We found that diking and freshwater rewetting caused a distinct freshening and an efficient depletion of the brackish sulfate reservoir by dissimilatory sulfate reduction (DSR). Despite some legacy effects of brackish impact expressed as high amounts of sedimentary S and elevated electrical conductivities, contemporary metabolic processes operated mainly under sulfate-limited conditions. This opened up favorable conditions for the establishment of a prospering methanogenic community in the top 30–40 cm of peat, the structure and physiology of which resemble those of terrestrial organic-rich environments. Locally, high amounts of sulfate persisted in deeper peat layers through the inhibition of DSR, probably by competitive electron acceptors of terrestrial origin, for example Fe(III). However, as sulfate occurred only in peat layers below 30–40 cm, it did not interfere with high methane emissions on an ecosystem scale. Our results indicate that the climate effect of disturbed and remediated coastal wetlands cannot simply be derived by analogy with their natural counterparts. From a greenhouse gas perspective, the re-exposure of diked wetlands to natural coastal dynamics would literally open up the floodgates for a replenishment of the marine sulfate pool and therefore constitute an efficient measure to reduce methane emissions.

Methane Emissions from Estuarine Coastal Wetlands: Implications for Global Change Effect

2019 ◽  
Vol 83 (5) ◽  
pp. 1368-1377 ◽  
Author(s):  
Lijie Liu ◽  
Dongqi Wang ◽  
Shu Chen ◽  
Zhongjie Yu ◽  
Yunkai Xu ◽  
...  
Keyword(s):  
Global Change ◽  
Coastal Wetlands ◽  
Methane Emissions ◽  
Change Effect ◽  
Estuarine Coastal

scholarly journals Field-scale simulation of methane emissions from coastal wetlands in China using an improved version of CH4MOD wetland

2016 ◽  
Vol 559 ◽  
pp. 256-267 ◽  
Author(s):  
Tingting Li ◽  
Baohua Xie ◽  
Guocheng Wang ◽  
Wen Zhang ◽  
Qing Zhang ◽  
...  
Keyword(s):  
Coastal Wetlands ◽  
Methane Emissions ◽  
Field Scale

Methane emissions from riverine and swampy coastal wetlands: influence of open and macrophyte-infested areas

2011 ◽  
Vol 16 (4) ◽  
pp. 265-272 ◽  
Author(s):  
Christopher Mulanda Aura ◽  
Safina Musa ◽  
Erick Ochieng Ogello ◽  
Levy Michael Otwoma ◽  
Wainaina Miriam ◽  
...  
Keyword(s):  
Coastal Wetlands ◽  
Methane Emissions

scholarly journals 197 Effect of STC-4771, An Intermediate of ABA Synthesis, on the Anthocyanin Accumulation in Grapes

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 425A-425
Author(s):  
W.S. Lee ◽  
J.C. Lee ◽  
Y.S. Hwang
Keyword(s):  
Anthocyanin Synthesis ◽  
Anthocyanin Content ◽  
Internal Factors ◽  
External Application ◽  
Grape Berries ◽  
Color Development ◽  
Agricultural Use ◽  
Favorable Conditions

The coloration of grape berries depends on the anthocyanin synthesis during maturation. The quality of berries is often decreased due to the poor color development when berries are grown under unfavorable environments and/or inadequate internal factors are involved. It has been well-known that the level of ABA at ripening is closely associated with anthocyanin synthesis; thus, the external application of ABA results in the increase of anthocyanin content even in berries grown under favorable conditions. However, the agricultural use of natural ABA is not possible because of high prices. This experiment was conducted to study the potential of STC-4771 as a substitute for ABA. The effect of STC-4771 was studied in `Kyoho', `Pione', and `Delaware' grapes. Chemicals were applied when ≈10% of berries in a cluster were colored. In `Kyoho', anthocyanin synthesis was enhanced at a concentration of 100 mg/L and there was a trend in color enhancement in `Pione', regardless of treatment concentration, between 10 to 40 mg/L. However, no clear effect was found in `Delaware' at 50 to 100 mg/L. In an in vitro experiment, anthocyanin was only increased when an adequate amount of sucrose (0.6 m) was added in the incubation medium under light. Natural ABA effectively increased the anthocyanin content of berry segments even under shading condition through four bagging materials, but no effect was confirmed in STC treatment.

Northern soybean varieties: climate effect on growth, development and yield

2019 ◽  
Author(s):  
Г. Гатаулина ◽  
Н. Заренкова ◽  
С. Никитина
Keyword(s):  
Weather Conditions ◽  
Crop Productivity ◽  
Stress Factors ◽  
Climate Effect ◽  
Experimental Station ◽  
Yield Production ◽  
Climate Stress ◽  
Ecosystem Condition ◽  
The One ◽  
Favorable Conditions

Повышение урожайности и её стабилизация у сои необходимы для решения проблемы дефицита растительного белка, сокращения импорта сои и обеспечения белковой независимости России. Скороспелые сорта сои северного экотипа Магева, Светлая и Касатка допущены к производству в Центральном регионе. Актуальность темы определяется необходимостью выявления стрессовых факторов, связанных с влиянием погодных условий на формирование урожайности и её нестабильность у различных сортов сои. Полевые опыты проводили в 20142018 годах на Полевой опытной станции РГАУМСХА им. К. А. Тимирязева на окультуренной дерновоподзолистой почве. Вариабельность показателей формирования урожайности оценивалась по коэффициенту вариации (V). В исследованиях установлена достаточно сильная вариабельность и нестабильность урожайности у сортов сои в зависимости от изменчивости погодных условий в разные годы. Продолжительность вегетации от всходов до созревания составила в среднем 90102 дня, что на 2025 дней меньше, чем в предшествующие годы, видимо, изза потепления климата. Максимальная за вегетацию высота растений изменялась у сорта Магева от 39 до 101 см в зависимости от условий года (V 30,8), у более скороспелого сорта Касатка от 31 до 69 см (V 28,9). В исследованиях подтверждено, что период цветения и образования плодов продолжительностью 2025 дней критический для формирования урожая. Средняя урожайность сортов при недостатке влаги в этот период (в 2014, 2017 годах) была в пределах 0,91,2 т/га при благоприятных условиях (в 2015, 2018 годах) она составила 2,52,8 т/га. В этот период одновременно с интенсивным вегетативным ростом определяются максимальные за вегетацию площадь листьев, число плодов и семян в расчёте на единицу площади (1 м2, 1 га). Коэффициент вариации (V), отражающий степень влияния погодных условий на величину площади листьев и урожайность семян, у сорта Магева составил соответственно 40,4 и 47,5, у сорта Касатка 32,5 и 30,7. Установлено, что предшествующее состояние агроценоза, особенно в критический период (цветение и образование плодов), в значительной мере определяет в последующем величину компонентов урожайности и непосредственно урожайность семян. This investigation took place in 20142018 at the Field Experimental Station of the Russian Timiryazev State Agrarian University on sodpodzolic soil. It is important to determine climate stress factors influencing soybean productivity. Weather conditions greatly affected soybean yield variability. Shortseason northern varieties of soybean such as Mageva, Svetlaya and Kasatka performed as objects of study. Growing season from germination to maturation averaged to 90102 days which was 2025 days less, than in previous years, apparently due to climate warming. Trait variability was determined via the variation coefficient (V). Mageva height varied within 39 and 101 cm depending on the year (V 30.8), the one of Kasatka from 31 to 69 cm (V 28.9). 2025day period of flowering and bean formation is crucial for yield production. Soybean productivity averaged to 0.91.2 t ha1 in 2014 (water deficit) and 2.52.8 t ha1 in 2015 and 2018 (favorable conditions). Leaf square area, bean and seed number per square unit were determined at this time. V of leaf area and seed yield amounted to 40.4 and 47.5 for Mageva and 32.5 and 30.7 for Kasatka. Ecosystem condition influenced significantly crop productivity.

Mars: was There an Ancient Eden?

1997 ◽  
Vol 161 ◽  
pp. 203-218 ◽  
Author(s):  
Tobias C. Owen
Keyword(s):  
Positive Answer ◽  
Biogenic Elements ◽  
Habitable Zones ◽  
The Face ◽  
The Origin Of Life ◽  
Early Mars ◽  
Favorable Conditions ◽  
Open Question ◽  
Rocky Planets ◽  
Impact Erosion

AbstractThe clear evidence of water erosion on the surface of Mars suggests an early climate much more clement than the present one. Using a model for the origin of inner planet atmospheres by icy planetesimal impact, it is possible to reconstruct the original volatile inventory on Mars, starting from the thin atmosphere we observe today. Evidence for cometary impact can be found in the present abundances and isotope ratios of gases in the atmosphere and in SNC meteorites. If we invoke impact erosion to account for the present excess of129Xe, we predict an early inventory equivalent to at least 7.5 bars of CO2. This reservoir of volatiles is adequate to produce a substantial greenhouse effect, provided there is some small addition of SO2(volcanoes) or reduced gases (cometary impact). Thus it seems likely that conditions on early Mars were suitable for the origin of life – biogenic elements and liquid water were present at favorable conditions of pressure and temperature. Whether life began on Mars remains an open question, receiving hints of a positive answer from recent work on one of the Martian meteorites. The implications for habitable zones around other stars include the need to have rocky planets with sufficient mass to preserve atmospheres in the face of intensive early bombardment.

Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

1996 ◽  
Vol 54 ◽  
pp. 160-161
Author(s):  
J. Fink
Keyword(s):  
Electronic Structure ◽  
Conducting Polymers ◽  
Conjugated Polymers ◽  
Electron Acceptors ◽  
Electron Donors ◽  
Light Emitting ◽  
One Dimensional ◽  
New Class ◽  
Electrical Conductivities ◽  
Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

Intraindividual Variability and Stability of Affect and Well-Being

GeroPsych ◽  
2013 ◽  
Vol 26 (3) ◽  
pp. 185-199 ◽  
Author(s):  
Christina Röcke ◽  
Annette Brose
Keyword(s):  
Age Differences ◽  
Well Being ◽  
Subjective Well Being ◽  
Emotional Experiences ◽  
Short Term ◽  
Regulatory Processes ◽  
Functional Implications ◽  
Methodological Approaches ◽  
Underlying Processes

Whereas subjective well-being remains relatively stable across adulthood, emotional experiences show remarkable short-term variability, with younger and older adults differing in both amount and correlates. Repeatedly assessed affect data captures both the dynamics and stability as well as stabilization that may indicate emotion-regulatory processes. The article reviews (1) research approaches to intraindividual affect variability, (2) functional implications of affect variability, and (3) age differences in affect variability. Based on this review, we discuss how the broader literature on emotional aging can be better integrated with theories and concepts of intraindividual affect variability by using appropriate methodological approaches. Finally, we show how a better understanding of affect variability and its underlying processes could contribute to the long-term stabilization of well-being in old age.

Validating an efficient measure of responsivity in father–child interactions.

2020 ◽  
Author(s):  
Nina Sokolovic ◽  
Sahar Borairi ◽  
Michelle Rodrigues ◽  
Michal Perlman ◽  
Jennifer M. Jenkins
Keyword(s):  
Efficient Measure
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