Farmers perception of soil and watershed degradation and the assessment of soil nutrients status under agroforestry systems in the Western Highlands of Cameroon: Case of Ako sub division

Abstract

The objective of this study was to assess farmers' perception regarding the activities which degrade the soil and watershed and to analyze soil nutrients status under different agroforestry systems. The aim of the study was to identify and promote locally-known agroforestry-based practices for soil and watershed conservation in the savannah highland area of Cameroon. Semi-structured questionnaires were administered to 120 farmers purposively selected from 10 villages in the Ako sub division characterized by favorable environmental conditions for agricultural production and the presence of agroforestry systems. The 10 villages were classified following a stratified sampling based on the degree of degradation of the soil and the watershed. Ako sub division was chosen because it is a priority zone for agricultural production and some of the practices are unsustainable leading to soil and watershed degradation. Soil samples were collected from each of the agroforestry systems found in the villages sampled and were analyze for soil nutrients status. The soil nutrients that were analyzed are: Organic matter by the wet oxidation method; exchangeable cations; cation exchange capacity; total nitrogen by Kjedahl method; available phosphorus by Bray II method and carbon to nitrogen ratio. The results showed that farmers perceived poor farming methods (33.10%) and deforestation (29.58%) as the main activities degrading the soil and the watershed. The standard values developed were used to compare the level of soil nutrients in each agroforestry system. The results of the soil analysis under each agroforestry system in Ako indicated that, soils were highly deficient in phosphorus in all the systems. The values were very low in all the systems ranging from 0.21 in palm agroforestry system to 0.46 in cocoa agroforestry system. Based on the level of organic matter and cation exchange capacity observed in the different farms, the agroforestry systems that should be promoted are: Coffee agroforestry systems, and cocoa agroforestry systems.

Assessing the Role of Agroforestry in Soil Fertility Improvement in Mbelenka-Lebialem, Southwest Cameroon

“…Since the slash and burn practice and the improved fallow were not prominent, the two main agroforestry practices identified in this area were life fences (AFP1) and scattered trees on farm lands (AFP2). This finding is different from the findings of Munjeb (2018), and Awazi et al (2019) who found a multitude of agroforestry practices on farmlands in north western Cameroon. Other studies undertaken by Nair (1989) and Nair (1993) found a multitude of agroforestry practices implemented by farmers across the tropics.…”

“…This is the first study in Cameroon to produce such unprecedented findings, showing that scattered trees on croplands play a major role in improving soil fertility in south western Cameroon. Nevertheless, other studies have equally shown that agroforestry practices in general have the capacity to improve soil fertility (Young, 1997;Asaah et al, 2011;Leakey, 2017;Awazi & Tchamba, 2018;Munjeb, 2018).…”