Ecological Study Of The Natural Regeneration Of The Woody Species In Enclosed Areas In Raya Azebo Woreda Southern Zone Tigray

Plant Biology And Biodiversity Management Project Topics

Get the Complete Project Materials Now! ยป

The study was conducted in Raya Azebo Woreda, Southern Tigray at about 662rnkm from Addis Ababa. It is under severe pressure due to grazing, anthropogenicrnactivities and rainfall fluctuations. Floristic composition, natural regnerationrnand soil analysis were assessed. Data were collected from three area closuresrnand their adjacent grazed lands using preferential and systematic samplingrnprocedures. Vegetation data were collected from a total of 90 sampling plotsrnand each field site comprised of 30 plots. In each of the study sites, sample plotsrnhaving an equal size of 20 m x 20 m were designated as the main plots used torninvestigate the densities and distribution of woody species. Moreover, eachrnmain plot was divided into five smaller sub-plots of sizes 5 m x 5 mrnfor regeneration counts (seedlings and saplings) and sizes of 2 m x 2 m forrnmeasuring cover abundance of herbaceous layers (grasses and forbs) in thernwoodland. In each sampling plot diameters of each woody species andrnenvironmental variables were recorded. From each plot, soil samples wererncollected to analyze the following edaphic parameters: soil pH, soil texture,rnavailable phosphorus, total nitrogen, cation exchange capacity, exchangeablernbases and soil conductivity. A total of 133 species representing 45 families werernrecorded. Fabaceae followed by Poaceae, Asteracae and Euphorbiaceae werernthe most dominant families in the study area. Five plant community types werernidentified from the hierarchical cluster analysis and named after two dominantrnspecies in each cluster. The density of all seedlings were 410 individuals/harnwhile the total sapling density was about 212 individuals/ha. The overallrnregeneration status of the study area was found to be good regenerationrn(5.56%), fair regeneration (55.56%), poor regeneration (22.22%) and nornregeneration (16.67%). The major factors affecting the regeneration of speciesrnin the woodland are frequent rainfall fluctuations, anthropogenic distrubancesrnand grazing pressures. The influential environmental variables of the studyrnarea were altitude, pH, EC, Na, K, Ca, Mg, CEC, TN, OM, P, Sand%, Silt% andrnClay%. The proportion of sand, silt and clay contents of the study arearnwas 66.58%, 21.66% and 11.78% respectively which impliess the soils in the arearnwas sand dominated. The five textural classes of soil identified in the studyrnareas were sandy loam followed by sandy clay loam, clay loam, loamy sandrnand loam. The soil pH in the area ranges from neutral (7.0 - 7.3) to stronglyrnalkaline (8.5 - 9.0) because the pH of dryland soils could be affected by therndeposition of unleached exchangeable cations on the soil surface due torninsufficient rainfall, hence, keeping the soil pH high.

Get Full Work

Report copyright infringement or plagiarism

Be the First to Share On Social



1GB data
1GB data

RELATED TOPICS

1GB data
1GB data
Ecological Study Of The Natural Regeneration Of The Woody Species In Enclosed Areas In Raya Azebo Woreda Southern Zone Tigray

210