Skip to main content

N2O emissions from Arctic soils not as low as previously thought: study (downtoearth)

A new study from the University of Eastern Finland presents, for the first time, the isotopic fingerprint of nitrous oxide produced by Arctic soils. The finding opens new avenues for predicting future trends in atmospheric nitrous oxide as well as identifying climate change mitigation actions in the Arctic, a region that is particularly sensitive to climate change.

Nitrous oxide (N2O) is a powerful greenhouse gas and also the second largest contributor to ozone depletion in the stratosphere. It is produced naturally by soils, with agricultural and tropical rainforest soils being the main sources of N2O to the atmosphere. Until recently, scientists assumed that nitrous oxide emissions were negligible in colder climate regions like the Arctic and sub-Arctic.

This assumption, however, was contradicted by scientists from the University of Eastern Finland a decade ago, when they discovered that bare peat surfaces in permafrost peatlands are releasing high amount of N2O, despite the general nitrogen limitation of tundra ecosystems. Since then, N2O emissions and their underlying processes have been the object of plenty of research and, also, debate.

In a new study, researchers from the University of Eastern Finland, together with colleagues from the Venezuelan Institute for Scientific Research (IVIC) and the University of California, Berkeley, explore the isotopic composition and potential sources of nitrous oxide emitted by soils in the sub-Arctic tundra. The study explores new frontiers in polar science, and the approach used establishes a legacy of data and methodologies that have the potential to link the Arctic ecosystem with the global N2O cycle.

In the study, the researchers examined nitrogen and oxygen isotopes in N2O samples collected from permafrost peatland sites in northwestern Russia. Using "site preference" analysis, the scientists also identified the specific isotopes occupying two different nitrogen sites within the nitrous oxide molecule. The study presents for the first time the isotopic fingerprint of N2O produced by soils of Arctic Tundra, thereby contributing to an understanding of N2O production mechanisms in this understudied environment.

Since different microbial processes leave distinct isotopic fingerprints on nitrous oxide, the researchers also hoped to figure out the relative amount of nitrous oxide emitted by different nitrogen-processing microbes in the tundra soils. The results suggest that the N2O emissions from bare tundra peat soils might be due to nitrifier denitrification, a microbial process that transforms ammonia (NH4) into N2 in a series of steps, one of which produces nitrous oxide. However, in the study year, N2O emissions were low compared to previous years, and the reasons for high emissions are still unclear. The isotope data was not conclusive enough, and even the sophisticated site preference technique did not provide enough information to tease out the relative roles of different microbes.

Nonetheless, the findings are valuable because isotopic nitrous oxide data from the Arctic and sub-Arctic are extremely rare. The findings could aid predictions of future trends in atmospheric nitrous oxide and help to identify mitigation actions in the Arctic, a region that is particularly sensitive to climate change. In the future, enhanced N2O emissions from natural soil such as sub-Arctic tundra might mask the isotope effect caused by mitigation actions derived from agriculture.

Popular posts from this blog

Indian Polity Elections (MCQ )

1. Who of the following has the responsibility of the registration of voters
a) Individual voters
b) Government
c) Election commission
d) Corporations


2. Democracy exists in India, without peoples participation and co operation democracy will fail. This implies that
a) Government should compel people to participate and cooperate with it
b) People from the government
c) People should participate and cooperate with the government
d) India should opt for the presidential system


3. Which of the following are not the functions of the election commission
1) Conduct of election for the post of the speaker and the deputy speaker, Lok sabha and the deputy chairman, Rajya sabha
2) Conduct of elections to the state legislative assemblies
3) Deciding on all doubts and disputes arising out of elections

a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 2

4. Which of the following electoral systems have not been adopted for various elections in India
1) System of direct elections on the basis of adult suffrage
2…

El Nino may make a comeback in 2017, but unlikely to affect southwest monsoon (downtoearth,)

In 2016, the world witnessed the strongest El Nino on record, which resulted in above average temperatures. The year experiences record-breaking heat for nine consecutive months. It had also ruined the Indian monsoon for two years. After two successive droughts in 2014 and 2015, last year witnessed erratic rainfall both in terms of geographical spread and time. Thanks to El Nino, the southwest monsoon in 2014 and 2015 witnessed a deficit of 11 and 14 per cent respectively.

While the 2016 monsoon season in India saw 97 per cent rainfall, it was far less than the 106 per cent that the India Meteorological Department (IMD) had forecast in July. The lesser-than-expected rainfall, especially in the second half of the monsoon season, has been attributed to the absence of a strong La Nina phenomenon in the equatorial Pacific Ocean that is known to help the Indian monsoon.

According to a recent forecast by the National Oceanic and Atmospheric Administration (NOAA), there’s a 50 per cent chan…

Current Affairs MCQ for UPSC Exams – 21 December 2016

Q.1- Which of the following is/are correct regarding Nirbhaya missile?

1. It is a cruise missile
2. It is hypersonic in speed
A. 1 only
B. 2 only
C. Both
D. None

Q.2- Khanjar-III is military exercise between which of the following countries?

A. India and Russia
B. Russia and China
C. India and Kyrgyzstan
D. Russia and Afghanistan

Q.3- UPI has been in news recently, what is the full form of UPI?

A. Unified Payment Interchange
B. Unified Payment Interface
C. Unified process interchange
D. Unified process interface
 .
.
.
.

.
.
.
.
.
.
.
.
.
.
.
.
.
.

.
.
.
.
.
.
.
.
.
.
Answer  1-A, 2 -C, 3-B