Extreme Temperature Diary- Friday November 20th, 2020/ Main Topic: Miscanthus Grass…One Plant To Use In Our Efforts To Combat Climate Change

The main purpose of this ongoing blog will be to track United States extreme or record temperatures related to climate change. Any reports I see of ETs will be listed below the main topic of the day. I’ll refer to extreme or record temperatures as ETs (not extraterrestrials).😉

Main Topic: Miscanthus Grass…One Plant To Use In Our Efforts To Combat Climate Change

Dear Diary. We all know that plants are the best natural way to absorb carbon dioxide and store carbon, taking it away from the atmosphere such that its greenhouse effect becomes a bit less. Scientists are learning much about which plants store the greatest amount of carbon for the least effort on the part of us humans to grow them. For today’s main subject let’s focus on one plant that you need to bring into your orbit. It never dawned on me that a common decorative plant around the southern United States that I commonly called “sea grass,” learning that term from my parents, could be a great tool to combat climate change until now. Every time I would go to the beach this plant was everywhere during the 1960s and 1970s and really enhanced the beauty of coastal areas. Later during the 1980s I noticed that around the Atlanta area seagrass was planted to decorate posh apartment communities. Now just about every southern lawn has seagrass planted as an ornamental shrub.

Most varieties of seagrass are very hardy, so this plant need not be confined to the U.S. South. Indeed, it can be grown in just about everywhere that there is not a polar climate. Around the planet this decade seagrass or rather, miscanthus, has been discovered to absorb carbon very well and could be a great biofuel. To learn more about the wide varieties of miscanthus, please read this Wikipedia article:

https://en.wikipedia.org/wiki/Miscanthus

Winter miscanthus, an ornamental grass, growing in Southern Ontario, Canada

For more details on this wonderful resource let’s turn to this BBC article:

https://www.bbc.com/news/uk-wales-mid-wales-17402684

And this more recent blog from the same university referred to from the 2012 BBC piece:

https://pwllpeiran.org/category/miscanthus/

MISCANTHUS

Energy to burn

by Amanda Holder (a PhD student at Aberystwyth University working on the multi-centre MAGLUE research programme)

As I have spent a lot of time over the past two years crawling around a field not far from the offices at Pwllpeiran I thought it would be a good idea to explain that there was a purpose to it!  It was all in an effort to record soil emissions of the greenhouse gas nitrous oxide emitted during the period of land preparation and planting of a new crop of Miscanthus (of course, why else!).

In order to combat climate change there is a need to reduce emissions of greenhouse gasses such as carbon dioxide, nitrous oxide and methane into the atmosphere. Producing energy from plants to reduce the use of traditional fuels such as coal and gas can help to do this.  Miscanthus is a tall perennial grass, similar in appearance to bamboo, which can grow up to 3 metres in one growing season. Harvested annually its rapid growth makes it good for use as a biofuel (being burned to produce electricity).

Amanda 2

Miscanthus growing in plots at Pwllpeiran

As with all plants Miscanthus absorbs carbon dioxide from the air during growth.  However, it is important that the full greenhouse gas implications of converting land to Miscanthus are understood. This is where I come in.

The period of land use change can be considered a ‘hotspot’ for release of greenhouse gasses from the soil due to the  disturbance involved.  To investigate the extent of soil nitrous oxide fluxes during the establishment of Miscanthus a set of 12 trial plots were set up at Pwllpeiran.  Two types of Miscanthus (the commercially available variety and a new hybrid) were planted using different reduced tillage methods, with some plots retained as sheep grazed pasture for comparison. Minimum tillage (soil cultivated to a shallow plough depth before planting) and no tillage (Miscanthus planted in slots cut into the ground) methods were used for the commercial variety, and the new hybrid was planted with minimum tillage under a film mulch layer.

Amanda 4

The new Miscanthus hybrid being planted.

Amanda 3

The plots set up and testing soil emissions when grazed grassland is converted to Miscanthus.

To record the soil nitrous oxide emissions the hard work started before planting began, with samples taken before any intervention, and then continuing until the plants were 18 months old. To do this, in each plot, a circular plastic ‘collar’ was inserted into ground and then every two weeks a lid was clamped to the collar creating an air tight chamber.

A few spare chamber lids were stored in the field and proved to be popular with local wildlife …

Amanda 6

Field vole nest, latrine, and escape hole made underneath a spare chamber lid that was stored in the field.

…but don’t worry the vole kept his home for the year as the spares lids weren’t needed!

Samples of air were taken from inside the chamber through a rubber seal using a syringe. These were taken at 15 minute intervals over the period of one hour. The samples were then taken to the Centre for Ecology & Hydrology at Lancaster (a partner in the project) where they were analysed for levels of nitrous oxide.

Amanda 7

Gas chromatography machine used to analyse the samples of air taken from inside the sealed chambers.

In the end the study was more than worth burning up some of my own energy!  The results obtained can be used to help balance the pros and cons of land use change to Miscanthus.  It was found that soil nitrous oxide emissions from the cultivated plots were higher than the uncultivated sheep pasture, but levels were similar to those for when a grass ley is reseeded. There was no difference between the cultivation methods tested, or the type of Miscanthus. Work with mature crops of Miscanthus had already shown that their fluxes are very similar to pasture.  When specific emissions related to the cultivation ‘hotspot’ are put into the context of the 15-20 year crop life time the impact is small and overall greenhouse gas balances for using Miscanthus are less than for coal or natural gas.

This July we see yet another study which could help agricultural interests breed and utilize miscanthus:

https://www.sciencedaily.com/releases/2020/07/200728130821.htm

Quoting:

“As climate change becomes increasingly difficult to ignore, scientists are working to diversify and improve alternatives to fossil-fuel-based energy. Renewable bioenergy crops, such as the perennial grass Miscanthus, show promise for cellulosic ethanol production and other uses, but current hybrids are limited by environmental conditions and susceptibility to pests and diseases.”

“Breeders have been working to develop new Miscanthus hybrids for years, but the clonal crop’s sterility, complex genome, and long time to maturity make conventional breeding difficult. In a new study, University of Illinois researchers mine the crop’s vast genomic potential in an effort to speed up the breeding process and maximize its most desirable traits.”

As researchers continue to improve varieties of miscanthus, let’s all begin to utilize this plant in our own local world as an ornamental. To my worldwide friends, add this plant to your gardens and use it as an indoor house plant. In summary, miscanthus can greatly lessen your carbon footprint. This is some good news to end our week on this Friday.

Here is more climate and weather news from Friday:

(As usual, this will be a fluid post in which more information gets added during the day as it crosses my radar, crediting all who have put it on-line. Items will be archived on this site for posterity. In most instances click on the pictures of each tweet to see each article. The most noteworthy items will be listed first.)

Now here are some of today’s articles and notes on the horrid COVID-19 pandemic:

(If you like these posts and my work please contribute via the PayPal widget, which has recently been added to this site. Thanks in advance for any support.) 

Guy Walton “The Climate Guy”

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