A cross sectional comparison of chemical treatment on plant biodiversity at Neudamm farm, Namibia
This study determined the impact of Tebuthiuron application on plant biodiversity over a three-year period at Neudamm farm. A total of 40 (1m2) quadrats were randomly nested in three 250 m2 belt transects per each treatment to record the herbaceous plant density, species composition, dry matter and ground cover. Woody plant density, heights and canopy diameters were measured in each 250 m2 belt transects. A General Linear Model (GLM) procedure of SAS (2007) was used for analyses. The herbaceous biomass production was significantly higher (P < 0.05) in chemically treated site of 2015 (975 Kg DM ha-1) and least in the other two sites. The chemically treated site of 2016 had greater (P < 0.05) ground cover percentage than the other treatment sites. The canopy cover and woody plant densities in all woody height categories were higher (P < 0.05) in the control and chemically treated site of 2017, than the other two sites. The study concluded that the Tebuthiuron had impacted on the plant biodiversity of treated rangelands by improving the herbaceous plant species, biomass yields and reduced bush density. The study recommends that aftercare practices and application of arboricides be carried out routinely to allow herbaceous plants recovery.
Keywords: Bush encroachment, arboricides, plant density, biomass production, canopy