What is the current weather doing to our soils?

There has been plenty of media coverage of the current extremely hot and dry weather. The drought is revealing archaeological features, (see also here), and we can even see the browning of our landscape from space. But this drought is not good news for our ecosystems at all, and one example of that are the recent wildfires in the Peak District. These fires are not just bad news for the plants and animals that live there, but also they make large amounts of carbon that have been sequestered over many years go up in the air as CO2, and this can amplify climate change. Drought also affects our ecosystems more subtly than that, but the long-term consequences might be as severe.

We can all see the effect the drought is having on plants: lawns are turning yellow, corn leaves are rolling, and in extreme cases, trees even lose their leaves. They become inactive, and can even die. This is not just bad news for the plants, it is also bad news for the soil. When plants stop growing, they are not photosynthesing, and when they are not photosynthesising, they are not removing CO2from the atmosphere. A large part of this photosynthesised COgoes straight into the soil to fuel the activities of microbes, which carry out important functions such as the decomposition of plant litter and the release of nutrients for plant growth. Continue reading

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Soil boring? My take on the image problem of soil science.

I am passionate about soil, especially about soil biodiversity and how soil organisms and plants interact and control C and N cycling. I have studied soils since I started my undergraduate in 1996, and I have witnessed a complete turnaround when it comes to interest in soil biodiversity and the functions it performs. When I started my PhD, no one was interested in soil organisms and how they regulate crucial ecosystem processes that also happen to be central to sustainable agriculture. Now, everyone is interested – from farmers, to policy makers, to fellow ecologists.

Well, I say everyone, but that is clearly not the case. Soil is still remarkably unsexy. I will illustrate this with a little anecdote.

Last Friday, I met the third year Zoology student who had been assigned to do a final year Science Media Education Project with me. As we walked up the stairs, I asked her what her background was, and she replied and said: “….. and you study soils, right?” in a slightly too upbeat manner. We went to my office, and after finding out that she’d like to interact with primary school children, I suggested organizing a book launch family activity or classroom activity linked to a children’s book about an earthworm that I provided scientific advice for. I explained to her what the book is about (it is about a little worm with low self-esteem, who goes on a journey and meets lots of impressive animals, but eventually finds out that worms are crucial for soil health and plant growth), that the authors are based in Manchester, and that it will come out in February. I saw her face light up as she got increasingly enthusiastic, and I said: “You probably thought, oh no, I have to do a project on soil” to which she replied that she had indeed been a bit worried. When she left, I felt happy that I had been able to excite her about the project, but sad that she had been worried about studying soil.

Sadly, I can’t really blame her.

I, too, often feel deeply bored when I read about soil.

Why is this? Continue reading

Soil Carbon Storage: The Headache of Grazing

[This is a guest post by Thomas Ross, a 3rd year Biology student at The University of Manchester – he is currently doing a Science Media Project on the effects of grazing on soil C storage, which I am supervising. This blog post is part of his portfolio, and he has to reflect on its impact in his final submission. So don’t hesitate to leave your comment!]

The carbon stored in soil amounts to double that in the atmosphere and biomass combined and soil has the potential to sequester more. As atmospheric levels of carbon dioxide have been on the rise there has been an increase in global temperatures and climate change (here, the processes involved in soil carbon storage explained in more detail). The potential of the soil carbon reservoir to sequester this carbon from the atmosphere, and potentially ease the speed of climate change, can be influenced by our actions and the way in which we manage land. One such way is through the grazing of domestic livestock.

Grazing has the potential to modify ecosystems drastically and thus affect soil carbon storage. But how much is too much? Unfortunately, I cannot give you a definitive answer as the effects of grazing on soil carbon storage vary greatly. Some studies showing increases in soil carbon due to grazing, others decreases and some no changes at all. This causes a tricky problem when deciding how to manage livestock to ensure maximum soil carbon storage and withholding the interests of all stakeholders. Continue reading