Research proposal submitted for the fulfillment of degree of Bachelor of Science on Geography and Environmental Science

Title: Gully expansion: which factors are responsible?

By:Endale Demeku Derib

Jimma University

November, 2004 E.C.

Table of ContentsIntroduction..........................................................................................................................3Objectives............................................................................................................................3Material and methods..........................................................................................................3

Study area........................................................................................................................3Data collection.................................................................................................................4

Expected outputs..................................................................................................................5Time plan.............................................................................................................................5References............................................................................................................................5Appendices..........................................................................................................................5

Table of figures

List of tables

Table 1 Time plan of the study............................................................................................5

Introduction

Land degradation and desertification are the serious problems that we are facing to feed the increasing population of our globe. Both of this problems have direct impact of food security (production, and access to food), development of infrastructure like road and water supply, and daily safe life of the society. Land degradation has large implication on soil fertility, hydrological cycle, climate, stability of slopes, soil moisture status and so on. Soil erosion is one of the results of land degradation that is caused by wind and water. Many studies and personal observation show that gully expansion is one of the problems that combat daily life of the society at large and hinder developments of Ethiopia at large. Different attempts like soil and water conservation has done for long time. However, factors along space and time have not clearly known in advance that are responsible for the expansion of gullies from time to time. Road construction, expansion of farming, overgrazing, rainfall and others are expected to be the causes of gully expansion. This small study has prepared to be done to use field surveys, focal group discussion, interviews, GIS, satellite images and descriptive status to identify the most important factors for gully expansion so that future conservation methods will be planned according to the results.

Objectives

1. to quantify the impact of gully expansion on farm lands and development works2. to identify physical, social and administrative factors responsible for gully

expansion3. to evaluate field reality with satellite images

Material and methods

Study areaThe study will be done in Oromya regional state, Arsi zone, Sire woreda around Sire town. It is geographically located at Located in the Arsi Zone of the Oromia Region, this town has a latitude and longitude of 08°17′N 39°27′E Coordinates : 08°17′N 39°27′E with an altitude of 1793 meters above sea level. It is one of three towns in Dodotana Sire woreda.

….. to his assignment to delineate the border between Kenya and Ethiopia, C.W. Gwynn passed through Sire in late October 1908. He describes the settlement's location at the time as "halfway up the scarp" on the southern side of the Awash River, and Sire itself as

"a small Abyssinian village and customs post". He was struck by its "curious little church consisting of a stone-built cube, surmounted by a sharp steeple-like roof, also of stone", which he speculated was originally a Muslim shrine "similar to that at Sheikh Hussein and others in the Arussi country."[1]

Based on figures from the Central Statistical Agency in 2005, Sire has an estimated total population of 10,977 of whom 5,404 are men and 5,573 women.[2] The 1994 census reported this town had a total population of 6,141 of whom 2,931 were men and 3,210 women.

According to ----, the population of the woreda is……. Agriculture, both farming and livestock rearing, is the main livelihood of the area. Tef, wheat and onion production are highly used as a cash generation mechanism to increase household income and trade of the area. It is located near to the main market accesses of the country to Adama and Addis Ababa. The annual rainfall and temperature vary ----, respectively. Access to local road to the area has been a challenge for years due to gully expansion and short life span of the gravel road constructed several times.

Figure 1 Study area: Ethiopia with Oromia regional state (left) and Arsi with Dodota Sire woreda (right).

Data collection

1. Bio-physical data- Geographical data like location of gullies, forest, town, homestead, road network, farmlands, and others will be gathered and processed from different sources and methods. Digital Elevation Model (DEM) with 30 m resolution will be collected from ASTER . Slope, aspect, stream network and elevation will be processed on GIS software. Important land uses like village, main and rural road network, town, farmlands and forest and bush land areas will be identified and digitized from Google earth images with the help of personal experience of the area. Sample gullies will be taken from these land uses and gullies to be addressed at field study. Gully depth, width and length will me measured with a tape meter and road from the sampled gully.

2. Socio-economic data-

3. GIS and statistical analysis- Slope and aspect terrain analysis will be done on ArcGIS software. Gullies, road and foot path networks will be delineated from Google earth maps on ArcGIS avenue. Watershed for each selected gully will be delineated on GIS using field survey, and DEM analysis. The area, average slope, and other watershed properties will be dived on GIS. Length measurement from GIS analysis will be evaluated with field measurement so that accuracy of dimensional data from satellite data is identified. Finally, descriptive statistics of field measurement is used to identify major factors for gully expansion with the help for historical background of gully formation derived from the inhabitants and personal experience.

4.

Expected outputs

Land and soil lost due to gully expansionFactors that contributes for gully formation and expansionExperience on field measurement, GIS and statistical analysis

Time planThe study is proposed for 47 days that can consts several activities shown on Table 1.Table 1 Time plan of the studyNo. Activities Time (days)1 Proposal writing 5 ( to )2 Download web data 2 ( to )3 Process web data 15 ( to )4 Field data collection 10 ( to )5 Data analysis 10 ( to )6 Report writing 10 ( to )6 Draft submition 5 ( to )7 Final presentation 5 ( to )

References

Found on http://en.wikipedia.org/wiki/Sire,_Arsihttp://www.oromiyaa.com/images/Dodota%20Sire.pdf

AppendicesSome satellite images of the study area from Google earth

Large gully developed along Dera-Sire road near Merfe Gassala village.

Large gully developed along Sire-Koshim road that make farm land unproductive and challenge locomotion from farm to farm (In Allelu Shashe kebele to the way to Borora).

Sire town