Evaluation of Soil and Water Conservation Measures in Dejiel Watersheds, Choke Mountains, East Gojjam Zone of Amhara Region, Ethiopia

Masresha, Biele (2014) Evaluation of Soil and Water Conservation Measures in Dejiel Watersheds, Choke Mountains, East Gojjam Zone of Amhara Region, Ethiopia. Masters thesis, Addis Ababa University.

[img] PDF (Evaluation of Soil and Water Conservation Measures in Dejiel Watersheds, Choke Mountains, East Gojjam Zone of Amhara Region, Ethiopia)
Biele, Masresha.pdf - Accepted Version
Restricted to Repository staff only

Download (1MB) | Request a copy

Abstract

A field study was conducted in Dejiel watershed, East Gojjam, Ethiopia to assess the existing soil and water conservation practices and evaluate their sustainability. The study included biophysical field surveys, soil laboratory analyses and household level survey. Soil and water conservation (SWC) structures were widely practiced such as fanya juu terrace on cultivated lands and trench on closure areas in the watershed. A total of 80 fanya juu terraces and 29 trenches that lie in three randomly selected transect lines on farm lands and closure areas, respectively were investigated. Vertical interval, height (length for trench) and collection ditch's width and depth were measured against the standard values provided by MoARD. Soil samples were collected on cultivated land which SWC measures practiced with fanya juu terraces composed of seven, six and five years old fanya juu terraces stabilized with tree lucen (Chamaecytisus palmensis) and compared it with cultivated area where no SWC measures practiced through selected soil nutrient parameters. For each treatment, minimum of 5 representative samples were collected from 5 spots 20 m distance from each other. A total of 54 Household heads were interviewed through open-ended and close ended questionnaires to assess the community based watershed management practices in Dejiel watershed. Evaluation of SWC measures indicated that the quality of structures practiced in closure area was in good position compared to SWC structures implemented on cultivated lands. Fanya juu structures that were implemented on cultivated lands showed very significant differences in vertical back height and collection ditch’s width and depth. The existing fanya juu structures only met 20.6% and 9.16% with the recommended standard in vertical height and collection ditch’s depth respectively. The quality of trenches constructed on closure area fulfills the recommended standard. Soil analyses showed that organic matter (OM), total nitrogen (TN), available phosphorus, pH, and electrical conductivity are significantly (p≤0.05) affected by soil conservation measures. The non-conserved fields had significantly higher OM, TN, and electrical conductivity; compared to the conserved cultivated lands, perhaps due to prior differences of the lands at the start of the treatments, since areas already seriously affected are chosen for conservation. The crop field conserved in 2007 with fanya juu terrace had significantly higher OM content than all other conserved fields. Farmlands treated in 2009 (5-year old fanya juu bunds) had lower OM and total nitrogen when compared to 7-year old fanya juu bunds (2007 treated). However no significant difference occurred among conserved lands in total nitrogen and pH value. Farmlands treated in 2009 had the highest available phosphorus compared with the remaining conserved and non conserved cultivated lands. The household participation in the implementation of SWC plans was high while their participation in the planning and designing (61.1%), in monitoring and evaluation (64.8%) and taking corrective action (70.4%) was low. In terms of community benefits, 88.9% of the household respondents replied that the conservation works practiced fairly decreased the land degradation and plant depletion. Similarly 18.5% and 59.3% of the household respondents believed that SWC had improved and fairly improved their livelihood, respectively. From the study it was possible to conclude that, since SWC conserved cultivated lands differentiated across the years of constructed structures (stabilized with tree Lucerne), the measures had better held the soil in-situ and improved inter-terrace soil physical and chemical properties. This suggests that by applying soil conservation measures upstream, the erosion rate and the amount of silt entering streams has been reduced. Improving land productivity through SWC in the upstream areas is the means to cut the huge costs of silt cleaning in dams and irrigation canals of the downstream areas.

Item Type: Thesis (Masters)
Uncontrolled Keywords: SWC, land degradation, SWC sustainability, community participation
Subjects: G Geography. Anthropology. Recreation > GE Environmental Sciences
Q Science > Q Science (General)
Q Science > QE Geology
Divisions: Africana
Depositing User: Selom Ghislain
Date Deposited: 19 Sep 2018 14:15
Last Modified: 19 Sep 2018 14:15
URI: http://thesisbank.jhia.ac.ke/id/eprint/5403

Actions (login required)

View Item View Item