Changes in soil properties and nematode population status under planted and natural fallows in land use systems of southern Cameroon

Abstract

Changes in soil properties and nematode population status under Flemingia macrophylla [(Willd.) Merrill], Pueraria phaseoloides (Roxb.) Benth, and natural bush fallows were assessed in three villages in southern Cameroon. In each village, experiments were set up in a 4-5 year-old bush fallow dominated by Chromolaena odorata (L.) R. M.King and H. Rob and a more than 20 year-old secondary forest. Total aboveground biomass production of P. phaseoloides was 7.45 Mg ha -1 , 4.2 times higher than F. macrophylla (1.78 Mg ha -1 ; P \ 0.05). In two years (24 MAP), the soil bulk density under P. phaseoloides, F.macrophylla and the natural regrowth in both bush and forest land use systems decreased (P \ 0.05). Within the same period, there was a general improvement in aggregate stability. The particle size distribution changed over 3 years (36 MAP), such that at 0-10 cm depth, the percent sand content had reduced whiles the percent clay content had increased under all the fallow systems in both bush and forest land use systems (LUSs). Soil N also increased significantly (P \ 0.05) after cropping under all the fallow systems in both LUS. In contrast, soil organic carbon decreased, but the extent was lower under P. phaseoloides and F. macrophylla compared to the natural regrowth. Soil P also decreased after cropping under all the fallow systems in both LUS whereas decrease in Mg was only observed under P. phaseoloides. F. macrophylla had Mg content after cropping similar to the initial in both LUS. Soil contents of K and Ca were not significantly different over time under all the fallow systems. Comparing the initial Helicotylenchus multicinctus population to that at 12 MAP, both P. phaseoloides and F. macrophylla reduced density of H. multicinctus (P \ 0.05). However, when the initial population density was compared to that at 24 MAP only under P. phaseoloides was the reduction maintained. The study concluded that the general improvement in the soil physical properties, impacted positively on the N and organic carbon contents which were sustained to a larger extent under the planted fallows than the natural regrowth. Furthermore, P. phaseoloides could be used as one component for the biological control of Helicotylenchus multicinctus, a phytopathogenic nematode.

Soil macroporosity, physical properties and nutrient leaching after forest conversion to rubber and oil palm plantation in an Acrisol of Jambi, Indonesia

“…There was no significant difference among the land uses; however, secondary forest apparently had rather lower MWD than other land uses. These results were comparable with Banful and Hauser (2011) who studied aggregate stability in secondary forest and bush. Kara and Baykara (2014) also found lower aggregate stability in the forest soil compared to farmland and grassland.…”

Improving Food Security by Adapting and Mitigating Climate Change-Induced Crop Pest: The Novelty of Plant-Organic Sludge in Southern Nigeria

“…This might be explained by the deep rooting system of C. odorata that mobilizes soil mineral nutrients which are turned into organic and plant-available nutrients in conducive climate (Kushwaha et al 1981;Tondoh et al 2013). Other possible reasons for high contents of minerals in the C. odorata soil could be due to high contents of leaf biomass and earthworms (Tian et al 2000;Kone et al 2012), fast decomposing rate of C. odorata (Roder et al 1995), and the elevated activities of the soil microbes (Mboukou-Kimbasta et al 2007;Banful and Hauser 2011;Ngo-Mbogba et al 2015;Dawson and Schrama 2016). On the other hand, E. guineensis (EG) treatment had elevated soil organic carbon and total nitrogen in our study.…”

“…3 Year elements in the soil, while Chromolaena odorata increased the contents of soil organic carbon and other minerals especially in the favorable climate years. Several studies have reported the effects of the exotic plants and organic residues of V. amygdalina, C. odorata, and Elaeis guineensis on the soil chemical properties and microbes (Kushwaha et al 1981;Obatolu and Agboola 1993;Quansah et al 2001;Peveling et al 2003;Koutika et al 2004;Callaway et al 2004;Gbaruko and Friday 2007;Banful and Hauser 2011;Tondoh et al 2013;Agbede et al 2014;Gandahi and Hanafi 2014;Nurulita et al 2014;Ngo-Mbogba et al 2015;Ajayi et al 2016;Dawson and Schrama 2016;Veldhuis et al 2017).…”

Improving Food Security by Adapting and Mitigating Climate Change-Induced Crop Pest: The Novelty of Plant-Organic Sludge in Southern Nigeria

“…3 Year application of Vernonia amygdalina and fipronil (FP) elevated the concentrations of most trace elements in the soil, while Chromolaena odorata increased the contents of soil organic carbon and other minerals especially in the favorable climate years. Several studies have reported the effects of the exotic plants and organic residues of V. amygdalina, C. odorata, and Elaeis guineensis on the soil chemical properties and microbes (Kushwaha et al 1981;Obatolu and Agboola 1993;Quansah et al 2001;Peveling et al 2003;Koutika et al 2004;Callaway et al 2004;Gbaruko and Friday 2007;Banful and Hauser 2011;Tondoh et al 2013;Agbede et al 2014;Gandahi and Hanafi 2014;Nurulita et al 2014;Ngo-Mbogba et al 2015;Ajayi et al 2016;Dawson and Schrama 2016;Veldhuis et al 2017).…”