Population dynamics of Microtermes (Isoptera; Macrotermitinae) are investigated in the Southern Guinea savanna vegetation zone of Nigeria. Study sites were primary woodland, long-term maize and a randomised block experiment established from secondary woodland with woodland, pasture, sweet potato, groundnuts, yam and maize. The species assemblage Comprised of Microtermes allleo, Microtermes n.sp. c., Microtermes grassei, Microtermes/epidus, Microtermes subhyalinus. 2 Microtermes abundance and distribution (n/m2) to a soil depth of 1 metre are examined in Chapter Four. Community structure differed with vegetation cover. Abundance was generally higher in the wet compared to the dry season and abundance.was greatest in long-term maize and higher in newly cleared and cultivated sites than in woodland. M subhya/inus was the most abundant species in all vegetation types except long-term cultivated maize where M /epidus was the most abundant species. Changes in crop alter species abundance and Microtermes community structure. Microtermes fungus comb abundance (n/m2), individual dry weight (g) and total dry weight (g/m2) to a soil depth of 1 metre in primary and secondary woodland and short and long-term maize are examined in Chapter Five. Vegetation cover had an influence on seasonal changes in the abundance, individual and total dry weights of fungus combs. M subhyalinus fungus combs showed the greatest seasonal changes, in secondary woodland and short-term maize. Microtermes foraging activity on softwood baits with season, species and vegetation is examined in Chapter Six. Seasonal differences in foraging activity were recorded but differences over time were more significant. Foraging activity differed with vegetation and species. Percentage of baits attacked by species as a proportion of the total number of baits attacked by all species was the best indicator of foraging activity. Non-random foraging was identified for Microtermes with positive associations among M. subhya/inus, M. aluco and M. lepidus. Microtermes foraging activity on baits is compared with soil abundance in Chapter Seven using diversity indices and simple linear regression analysis. Foraging activity can give a more accurate indication of species richness than soil sampling. Foraging activity can be correlated positively with soil abundance, most significantly with wet season assessments.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:744234 |
| Date | January 1994 |
| Creators | Black, Helaina I. J. |
| Publisher | Queen Mary, University of London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://qmro.qmul.ac.uk/xmlui/handle/123456789/52083 |
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