Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Afrique du Sud → 2018 → Conservation agriculture and its impact on soil quality and maize yield : A South African perspective.

University of KwaZulu-Natal (2018)

Conservation agriculture and its impact on soil quality and maize yield : A South African perspective.

Sithole, Nkanyiso Justice.

Titre : Conservation agriculture and its impact on soil quality and maize yield : A South African perspective.

Auteur : Sithole, Nkanyiso Justice.

Université de soutenance : University of KwaZulu-Natal

Grade : Doctor of Philosophy (Crop Science) 2018

Résumé partiel
The countries in sub-Saharan Africa (SSA) are faced with the problem of soil degradation resulting from unsustainable soil management practices such as conventional tillage (CT) and the removal of soil biomass from crop land. Conventional tillage leads to deterioration of important soil physical properties, the decline in soil organic carbon (SOC) and increase the risk of soil erosion. The reduction of SOC further affects soil macrofauna which has important key roles in soil processes such as soil structural formation, decomposition of soil organic matter (SOM) and recycling of soil important nutrients. This combined with water scarcity, low inherent soil fertility, increasing population and the predicted negative impacts of climate change poses threat to the regions ability to self-supply enough food for current and future generations. In response to this conservation agriculture (CA) has been endorsed because of its powerful mechanism to adapt by increasing resilience to land degradation, drought and increasing water use efficiency. Soils under no-till CA have been recognised widely that they generally contain higher SOC, the key principal indicator of soil quality, than CT system. These responses, however, are site-specific and depends on soil type, cropping systems, climate, fertilizer application and other management practices. Moreover, most of the published literature on the effect of CA on soil quality parameters comes from cooler temperate regions. As a result, the effect of CA on soil quality parameters in sub-tropical semi-arid environments remains unknown or controversial. Therefore, the primary objective of the study was to assess the effect of no-till (NT), rotational tillage (RT), CT and nitrogen fertilizer application rates on selected physical, chemical and biological properties of the soil and, their influence on maize yield. The secondary objective of the study was to explore the use of visible to near infrared spectroscopy (VIS-NIRS) as a possible cheap alternative for SOC quantification.

Présentation

Version intégrale (1,58 Mb)

Page publiée le 4 janvier 2021