LEGUME ABUNDANCE TO EXPLORE THE LEGUME ABUNDANCE ALONG SUCCESSIONAL AND RAINFALL GRADIENT IN NEOTROPICAL FORESTSEDWIN NJOROGESCG200-1311/2015BOTANY DEPARTMENT LEGUME ABUNDANCE ALONG SUCCESSIONAL AND RAINFALL GRADIENT IN NEOTROPICAL FORESTSAccording to ( Gei, Danae& Powers,2018) the nutrient demands of regrowing tropical forests are partly satisfied by Nitrogen fixing legume trees, but those species are biased towards wet tropical regions. During the first three decades of natural forests regeneration, legume basal area is twice as high in dry compared to wet secondary forests, the tremendous ecological success of legumes is recently disturbed, water, limited forests is likely to related to both their reduced leaflets size and ability to fix N2 which together enhance legume drought tolerance and water use efficiency. Earth should incorporate these large scale successional and climate pattern of legume dominance to provide more accurate estimates of the maximum potential for natural Nitrogen fixation across forests.Forests contribute significance potion of the land carbon sink, but their ability to sequester CO2 may be constrained by Nitrogen, a major plant limiting plant nutrient.
Many tropical forests possesses tree species capable of fixing atmospheric Dinitrogen (Batter man, Hedin & Hall, 2013). According to(Barron, Parves &Hedin,2010) symbiotic Dinitrogen fixation is often invoked to explain the Nitrogen richness in tropical forests as ostensibly N2 –fixing tree can be major component of the community. Such argument assume Dinitrogen fixer are fixing Nitrogen when present.
Fixation of substantial in disturbed forests and some gaps but near zero in high Nitrogen soils of natural forests. Canopy legumes crossly regulates Nitrogen fixation leading to large variations in Nitrogen inputs across the landscape and low symbiotic fixation in mature forests despite abundant legumes (Barron et al, 2010).(Wielder, Cleveland &Lawrence, 2015) Uncertainties in terrestrial carbon cycle projection increase uncertainty of potential climate feedback. Efforts to improve model performance often include increased representation of biogeochemical processes, such as coupled Carbon-Nitrogen cycle.
The world greatest terrestrial stores of biodiversity and carbon are found in the forest of Northern south America, where largescale biogeographic patterns and process have recently began to be described (slvege, Pilman &Vazquez,2006).According to (pellegrin et al, 2016) tropical savannahs are hypothesized to be hotspots of Nitrogen- fixer diversity and actively because of the high disturbances and low Nitrogen characteristics of savannah landscapes. Comparison of abundances of Nitrogen Fixing Conditions using plant inventory studies across 566 plots in South America and Africa.Legume taxonomic composition differed strongly between secondary and mature rain forests and floristic similarities of legume between both forests types was only 34%. Successional changes in legume vegetation shares and taxonomic composition were weak within secondary regrowth through repeated slash and burn did affect legume vegetation (Gehrin, Munis & De souza, 2008).
According to (Meger &Chazdon ,2015) trees capable of symbiotic Nitrogen fixing are abundant in man tropical forests. In temperate forest, it is well known that Nitrogen fixers specialize in early successional niches, but in tropical forests successional trends of Nitrogen fixing species are poorly understood.References.Batterman, S. A et al(.2013) Key role of symbiotic dinitrogen fixation in tropical forests secondary succession, 224-227.
Barron, A. R,. Purves, D. W. & Hedin, l. O.
(2010) Facultative Nitrogen fixation by canopy legumes in lowland tropical forests, 511-520.Chazdon, R. L. et al(2017).
carbon sequestration potentialof second growth forest in the latin American tropics. Gehring, C., Muniz, F. h.
, &Gomes de souza,l. A., (2008) Leguminosae along 2-25 years of secondary forests succession after slash-and-burn agriculture and in mature rain forests of central Amazonia, 388-400.Hanster steege, h.
et al. (2006) Continental-scale patterns of canopy tree composition and function Amazonia, 444-447.Maga Gei, Danae M.
A. Rozendaal & Jeniffer s.Powers (2018) Nature of Ecology and EvolutionMenge, D. N.
L. & Chazdon, R.L. (2015) Higher survival drives the success of nitrogen fixing trees through succession in Costa Rican rainforests, 965-977.
Pellegrini, A. F. A., Staver,A. C.
, Hedin,l. o.,Charles-Dominique, T.& Tourgee,A (2016) Aridity not fire, favours nitrogen fixing plants across tropical savannah and forests biomes, 2177-2183.
Wieder, W.R., Cleveland, C. C., Lawrence, D.
M. & Bonan,G. b. (2015) Effects of model uncertainty on carbon cycle projections; Biological nitrogen fixation as a case study, 1-9.