Baby kangaroos can help in combatting climate change

Perjantai 19.5.2023 klo 19:30 - Mikko Nikinmaa

In addition to taking up immense land area as pasture, cattle causes the release of greenhouse gases directly. When they digest grass, they produce and burb methane, which is a strong greenhouse gas. This is because the bacteria in their fermenting stomach have methane as their end product.

Now, wouldn’t it be nice, if the methane release of cattle could be decreased? A recent study by Karekar and Ahring in Biocatalysis and Agricultural Biotechnology (Vol 47: 102526) “Reducing methane production from rumen cultures by bioaugmentation with homoacetogenic bacteria” has suggested that replacing methane-producing bacteria with acetate-producing bacteria in kangaroo babies’ faeces could completely prevent methane production, if the methane-producing bacteria were first eradicated. This finding is currently only done on rumen cultures, but if the change of bacterial consortiums can be done on commercial scale on cattle, some of the climate problems with cattle ranching would disappear. The fact that kangaroos can live with rumen  containing acetogenic bacteria indicates that they are compatible with mammalian herbivores. However, the efficiency of acetogenic bacteria may be lower than that of methanogenic ones.

Kommentoi kirjoitusta. Avainsanat: greenhouse gases, methane, cattle

Agricultural land use: unvegetated fields result in both erosion and carbon dioxide liberation

Sunnuntai 20.10.2019 klo 19:34 - Mikko Nikinmaa

The usual way of producing agricultural products: crops, potatoes, vegetables etc., is to plough and harrow the land and use artificial fertilizers. This leaves the land uncovered by plants for a long period of time, which leaves the soil vulnerable: rain and wind can remove organic material, and the fertility of soil decreases. The major reason for soil fertility is the organic material of soil, which recovers after cultivation, if the land remains covered with plants for a long period of time. However, the present agricultural practises do not allow adequate time for soil recovery, even though in principle the land fertility is a renewable resource. The land erosion results in decreased food production to increasing human population, and the need to clear forest to food production.

The decreased land fertility is not the only problem. The plant/grass-covered soil contains  huge amount of organic carbon, which is liberated as carbon dioxide when the soil is ploughed and harrowed, and the soil is without vegetation. The most pronounced carbo dioxide liberation occurs, when bog/marsh soil is dried. This increases respiration, i.e. carbon dioxide production, of soil (micro)organisms. This is particularly worrisome in Finland, as marshes have been dried to farmland, and as peat is extracted for energy production. Both cause disproportionate liberation of greenhouse gases, in fact, energy production using peat is climatewise worse than using coal.

This actually brings about the fact that if cattle is reared so that the animals feed out on grassland, the climate effect of cattle-based  products is much smaller than if the animals do not feed out on grass.

Kommentoi kirjoitusta. Avainsanat: climate change, agriculture, cattle, food production, peat