http://ir.bdu.edu.et/handle/123456789/11529 2001-01-13T05:52:20Z 2001-01-13T05:52:20Z Gashachew Yeshineh http://ir.bdu.edu.et/handle/123456789/13005 2022-02-03T11:55:17Z 2022-02-03T00:00:00Z

IMPACTS OF SETTLEMENT AND AGRICULTURAL EXPANSION ON FOREST COVER CHANGE IN WEST GONDAR ZONE, NORTH WEST ETHIOPIA Gashachew Yeshineh Huge number of settlement programs and unscientific agricultural expansion cause the reduction of forest cover. Thus, this study was conducted to detect the impacts of settlement and agricultural expansion on forest cover change in West Gondar zone, between the year1980 – 2020. To detect the impacts of settlement and agricultural expansion on forest cover; Landsat TM of 1980, ETM+ of 2000 and OLI-TIRS of 2020 were used to generate the land cover map of the study area. In addition to the detection; Field observation, focus group discussions, key informant interviews and remotely sensed data were used to analyze the cause, agent, management options, patterns and rate of land use land cover change. For the purpose of land-use change analysis; preprocessing, post-classification and change detection comparison were employed. Hence, the land use analysis result showed that the dramatic increment of farm land from 4962.711km2 (31.88 %) in 1980 to 8068.38km2 (51.8 %) in 2020 with an annual increment rate of 155.28 km2, whereas forest cover decreased from 9030.23km2 (58.01%) in 1980 to 6,123.95km2 (39.3 %) in 2020 with annual decreasing rate of -72.66km2 per annum. In order to check the precision of land use classification, the accuracy assessment of the classification was employed. Therefore, the accuracy assessment result for 2020 maps showed that an overall accuracy (85.81%) and kappa coefficient was (81%) for the classifications. The reason for the increment of agriculture and the decline of forest cover was due to huge number of settlements, unscientific large-scale agriculture expansion, charcoal production, fuel wood collection, house construction and road construction with the facilitator of investor, settler, resident and per time contractor were the major reasons. To overcome such problems: forest conservation approach should be participatory, large-scale farmers should include forest conservation practice in their agricultural license and strong awareness about the positive impacts of forest and the negative impact of deforestation should be delivered to the community of the study area

2022-02-03T00:00:00Z Temesgen Mengist http://ir.bdu.edu.et/handle/123456789/13004 2022-02-03T11:48:16Z 2022-02-03T00:00:00Z

EFFECTIVENESS OF EXCLOSURE FOR DEGRADED LANDSCAPES RESTORATION, THE CASE OF DENGORA AND KARITA-WUHA WATERSHEDS, NORTHWESTERN ETHIOPIA Temesgen Mengist Land degradation, which includes loss of vegetation cover, soil degradation, and nutrient depletion, is a severe ecological problem in Ethiopia's northern highlands particularly in Dengora and Karita-Wuha watershed. In Dengora and Karita-Wuha watershed, rehabilitation of degraded lands through exclosure has been undertaken as a response to the ever-increasing land degradation. Despite this issue, no studies have been conducted in the research area to assess the use of exclosures as a practice for preventing soil deterioration and thereby increasing agricultural production. This study was conducted in the Dengora and Karita-Wuha watershed East and West Belesa woreda, Central Gondar zone, in northern Ethiopian highland to assess the effectiveness of exclosures in improving degraded landscapes. In each landscape position (upper slope, middle slope, and foot slope) 20 by 20 m, 10 by 10 m and 5 by 5 m sampling plots were established for cultivated land, trees and bush & shrub respectively to conduct vegetation inventory. In each plot of the land uses, five small soil holes (four from corners and one at the center) were opened by auger in an ‘X’ design for soil sampling in 20cm depth. A total of 22 quadrat plots were examined at Dengora watershed, of which 9, 8 and 5 quadrat plots were in the exclosure, cultivated land with terrace and communal grazing land respectively. Similarly, a total of 26 plots were examined at the Karita-Wuha watershed, of which 13, 8 and 5 plots were in the exclosure, communal grazing land and farm village respectively. Vegetation was inventoried to analyze aboveground biomass and soil samples were collected for soil fertility and nutrient stock analysis. Aboveground biomass of different land use types was estimated from the height and diameter of vegetation by using an allometric equation. Status of fertility and nutrient stock of different land use types were assessed using OC, TN, AP. Analysis of variance was used to compare means between vegetation indices, aboveground biomass, soil fertility and nutrient stock among land uses. This study shows no significant differences (P > 0.05) among land use types in aboveground biomass, soil fertility and nutrient stock in both watersheds. Because exclosure land was substantially degraded before it was exclosed and has yet to be recovered in a short time. The result supports exclosures can only be successful in rehabilitating degraded areas if they are well managed and protected from human and animal disturbances for an optimum period.

2022-02-03T00:00:00Z Temesgen Mengist http://ir.bdu.edu.et/handle/123456789/13003 2022-02-03T11:44:47Z 2022-02-03T00:00:00Z

EFFECTIVENESS OF EXCLOSURE FOR DEGRADED LANDSCAPES RESTORATION, THE CASE OF DENGORA AND KARITA-WUHA WATERSHEDS, NORTHWESTERN ETHIOPIA Temesgen Mengist Land degradation, which includes loss of vegetation cover, soil degradation, and nutrient depletion, is a severe ecological problem in Ethiopia's northern highlands particularly in Dengora and Karita-Wuha watershed. In Dengora and Karita-Wuha watershed, rehabilitation of degraded lands through exclosure has been undertaken as a response to the ever-increasing land degradation. Despite this issue, no studies have been conducted in the research area to assess the use of exclosures as a practice for preventing soil deterioration and thereby increasing agricultural production. This study was conducted in the Dengora and Karita-Wuha watershed East and West Belesa woreda, Central Gondar zone, in northern Ethiopian highland to assess the effectiveness of exclosures in improving degraded landscapes. In each landscape position (upper slope, middle slope, and foot slope) 20 by 20 m, 10 by 10 m and 5 by 5 m sampling plots were established for cultivated land, trees and bush & shrub respectively to conduct vegetation inventory. In each plot of the land uses, five small soil holes (four from corners and one at the center) were opened by auger in an ‘X’ design for soil sampling in 20cm depth. A total of 22 quadrat plots were examined at Dengora watershed, of which 9, 8 and 5 quadrat plots were in the exclosure, cultivated land with terrace and communal grazing land respectively. Similarly, a total of 26 plots were examined at the Karita-Wuha watershed, of which 13, 8 and 5 plots were in the exclosure, communal grazing land and farm village respectively. Vegetation was inventoried to analyze aboveground biomass and soil samples were collected for soil fertility and nutrient stock analysis. Aboveground biomass of different land use types was estimated from the height and diameter of vegetation by using an allometric equation. Status of fertility and nutrient stock of different land use types were assessed using OC, TN, AP. Analysis of variance was used to compare means between vegetation indices, aboveground biomass, soil fertility and nutrient stock among land uses. This study shows no significant differences (P > 0.05) among land use types in aboveground biomass, soil fertility and nutrient stock in both watersheds. Because exclosure land was substantially degraded before it was exclosed and has yet to be recovered in a short time. The result supports exclosures can only be successful in rehabilitating degraded areas if they are well managed and protected from human and animal disturbances for an optimum period.

2022-02-03T00:00:00Z HABTEMARIAM TESHOME http://ir.bdu.edu.et/handle/123456789/13001 2022-02-03T08:56:23Z 2022-02-03T00:00:00Z

IDENTIFICATION OF YIELD LIMITING NUTRIENTS FOR SORGHUM (Sorghum bicolor (L.) Moench) YIELD, NUTRIENT UPTAKE AND USE EFFICIENCY ON VERTISOLS OF RAYA KOBO DISTRICT, NORTHEASTERN ETHIOPIA HABTEMARIAM TESHOME Low soil fertility accompanied with inbalanced fertilizer application during crop cultivation in Ethiopia and Amhara Region adversely reduced crop yield and affected soil quality. As a result, the response of major crops to fertilizer applications is often by far below the attainable and potential yields. Thus, this study was conducted to identify the most yield limiting nutrients for sorghum (Sorghum bicolor) through omission trial in Raya Kobo district of Amhara Region during 2020/21 cropping season. The test crop was Girana one sorghum variety. The treatments included: Control (no fertilizer), NPS, PSBZn, NPBZn, NSBZn, NPSB, NPSZn, NPSBZn, recommended NP and NPSKBZn. The experiment was laid out in RCBD design with three replications. A composite soil sample at a depth of 0-20cm was collected before the application of the treatments to determine soil pH, soil texture, organic Carbon, CEC, Total N, available P, S, exchangeable K, Zn and B determination following standard procedures. Grain and stalk samples of sorghum were collected from each plot for analysis of N and P uptakes. Agronomic data were also collected following standard procedures. The collected data were subjected to analysis of variance using SAS version 9.0 software. The analysis of variance showed that significantly higher grain yield (4620 kg ha-1) was obtained from NPKSZnB, while the lowest grain yield (2759 kg ha-1) was obtained from the control followed by N omitted (2805 kg ha-1) plots. A significant yield reduction was observed in nitrogen fertilizer omitted plots than others and there was no statistically significant yield difference between potassium, sulfur, boron and zinc omitted plots and recommended NP plots. In addition to grain yield, the highest agronomic efficiency of N (20.2kg grain kg-1 N) and P(28.92kg grain kg-1 P2O5) were recorded from plots treated with NPKSZnB and recommended NP, respectively. As a result research and development should focus on nitrogen to attain optimum sorghum yield for the study area, Phosphorus could also applied to maintain the fertility level in the optimum range.

2022-02-03T00:00:00Z