TERMITES
There are some 4 billion tons of them. It is said that about 700 kg of termites exist for every human on the planet. In terms of carbon churn and methane they contribute the most as compared to other living species on earth. They eat everything cellulose, often even living plant tissues.
The presence of termites across vast swathes of savanna creates a climate that is more severe. There is less humidity in the air, more violent rainstorms, less frequent rain. The type of plants that do manage to survive in termite areas are those which devote a great deal of energy to producing anti termite toxins. Acacias and all types of magnificent mahogany tress all derive from the selective pressure to avoid being gobbled up by termites.
The point is that not everything natural is necessarily good and wholesome, just because termites have been degrading their environment for hundreds of millions of years does not mean that their influence is desirable. termites do not like the cold. If they did, perhaps the soils of the temperate zones would be as poor as tropical soils.
The biomass per sq km of termites is often far greater than any other animal.
Back in 1989, a New Scientist article highlighted the role that termites play in methane emissions. At the time it was thought that only around 1% of methane emissions were caused by the digestive processes of the 250 trillion termites on Earth, but now the figure is thought to be around 3% of the total – still small, definitely natural and almost certainly out of our control. New CH4 emission data from a number of Northern and Southern Hemispheric, tropical and temperate termites, are reported, which indicate that the annual global CH4 source due to termites is probably less than 15 Tg. The major uncertainties in this estimate are identified and found to be substantial. Nevertheless, results suggest that termites probably account for less than 5% of global CH4 emissions.
Termites...The Danger is Real!
Termites cause more damage to homes than fires and all storms combined in the USA.
Homeowners insurance doesn't provide protection from the perils of termites.
There are more than 2,500 species of termites worldwide.
Termites cause damage to more than 600,000 U.S. homes with losses totaling over $2 billion annually.
Subterranean termite colonies are large, once swarming begins its numbers are between 60,000 and 1.5 million.
The total weight of all the termites on Earth is estimated to be much greater than the total weight of all the humans on Earth.
Methane emissions from termites are a function of the amount of feed consumed and the proportion of this that is converted into methane. Termites in these ecosystems emit between 1.07% (Holt, 1988) and 1.39% (Khalil et al., 1990) of the carbon they consume in the form of methane, the reminder being emitted as CO2 with very small traces of other gases such as chloroform. Feed consumption of termites can be very high in tropical environments with around 25-30% of the litterfall being eaten (Josens, 1983; Mott et al., 1985). Feed consumption by temites is a function of the termite biomass and the feed consumption per unit biomass. Of the carbon consumed by termites, 1.23% (average of measured emissions) was emitted in the form of methane, the reminder as CO2. Nitrous oxide emissions have also been measured from temite mounds in eastern Australia (Khalil, et al., 1990). Based on these measurements, emissions of nitrous oxide from termites were estimated to be 0.0125% of the weight of the carbon consumed assuming a fixed C:N ratio.
Subterranean termites graze about 100 kg / ha (Mott et al. (1985) for tropical savannas in Australia.
Termites annually consume food on an average rate of seven times of their own biomass.
Termites:
To assess the role of termite populations in the change of global atmospheric methane concentrations, we reevaluate the hypothesis that deforestation leads to higher populations of wood-feeding termites and to a significant increase of termite-emitted methane in areas of cleared and burned former primary rain forest. Calculations are based on a model that uses literature information on termite population size in primary forest and pasture 1 to 10 years after forest conversion, wood consumption and methane emission rates of termites. We use two scenarios based on low- and high-end parameters based on data from rain forests in Brazilian Amazonia. In the low-end scenario, termite population biomass is 25 kg x ha(-1) in primary forest; 4 kg x ha(-1) in year 1 after forest clearing, 51 kg x ha(-1) in a six-year-old pasture, and 4 kg x ha(-1) in a ten-year-old pasture. In the high-end scenario, all values are doubled and the initial breakdown in year 1 is omitted. Wood consumption rates are 49 and 270 mg wood x g termite(-1) x day (-1) and methane emission rates are 0.0023 and 0.0079 t of carbon released as methane per ton of carbon consumed, in the low- and the high-end scenario, respectively. In the low-end scenario no significant difference exists between the average termite population size in primary forest and pasture modeled over a ten-year period. In the high-end scenario the average population size of years 1 - 10 after clearing is only 31 per cent over that of primary forest. The population model data combined with the wood consumption rates allow for only 23-32.3 per dent of the wood biomass left from forest bum to be consumed by termites within 10 years. The changes in methane emissions from termite population change after deforestation were calculated using two approaches: "Cumulative net emissions" for the region, which measure the 1 0-year impact of a year's forest clearing (e.g. 1.38 x 10(exp 6) ha in 1990), increase by 0.000 1 to 0. 11 Tg CH4 in the 10 yea r-period in both scenarios, a negligible contribution to the increase of atmospheric methane concentrations of 45 Tg x yr(-1). The "annual balance of net methane emissions" from termites in all the different landscapes existing in the whole region in a single year (1990) increases by only 0.004 to 0.33 Tg CH4 (low- and high-end scenario) because of the large proportion of old clearings (> 10 years old) with low methane emission rates. Termite populations do not tend to increase as a function of the available wood mass only and therefore methane emissions from termites in cleared areas of former rain forest do not make a significant contribution to the increase of the global methane concentrations in the atmosphere.
1 teragram = 1000000000 kilograms
Termites may emit large quantities of methane, carbon dioxide, and molecular hydrogen into the atmosphere. Global annual emissions calculated from laboratory measurements could reach 1.5 x 1014 grams of methane and 5 x 1016 grams of carbon dioxide. As much as 2 x 1014 grams of molecular hydrogen may also be produced. Field measurements of methane emissions from two termite nests in Guatemala corroborated the laboratory results. The largest emissions should occur in tropical areas disturbed by human activities.
Termites belong to the insect order Isoptera, an ancient insect group that dates back more than 100 million years. The Latin name Isoptera means "equal wing"and refers to the fact that the front set of wings on a reproductive termite is similar in size and shape to the hind set.
There are more than 2,500 different types of termites in the world. However, most of this diversity can be lumped into four distinct groups: dampwood, drywood, subterranean, and mound builders. Mound builders do not occur in North America, but the other three species do. Dampwood termites are very limited in their distribution: most species are found only in California and the Pacific Northwest. Dampwood termites derive their name from the fact that they live and feed in very moist wood, especially in stumps and fallen trees on the forest floor. Drywood termites are common on most continents and can survive in very dry conditions, even in dead wood in deserts. They do not require contact with moisture or soil. Subterranean termites are very numerous in many parts of the world and live and breed in soil, sometimes many feet deep. Lastly, the mound builders are capable of building earthen towers 25 feet or more in height. Mounds may be located either in the soil or in trees, and where they occur in Africa, Australia, Southeast Asia, and parts of South America, they are very noticeable and remarkable.
Termites are very important in the Sahara Desert where their activity helps to reclaim soils damaged by drying heat and wind and the overgrazing by livestock.
Termites may produce up to two litres of hydrogen from digesting a single sheet of paper, making them one of the planet's most efficient bioreactors. Termites achieve this high degree of efficiency by exploiting the metabolic capabilities of about 200 different species of microbes that inhabit their hindguts. The microbial community in the termite gut efficiently manufactures large quantities of hydrogen; the complex lignocellulose polymers within wood are broken down into simple sugars by fermenting bacteria in the termite's gut, using enzymes that produce hydrogen as a byproduct. A second wave of bacteria uses the simple sugars and hydrogen to make the acetate the termite requires for energy. By sequencing the termite's microbial community, the DOE hopes to get a better understanding of these biochemical pathways. If it can be determined which enzymes are used to create hydrogen, and which genes produce them, this process could potentially be scaled up with bioreactors to generate hydrogen from woody biomass, such as poplar, in commercial quantities.
