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This paper explores factors influencing smallholder farmers’ attitudes towards integrated soil fertility management (ISFM). ISFM is paramount to improve soil fertility for sustainable agricultural productivity, especially in contexts where smallholder agriculture is an important local livelihood and economic activity, as in many countries of the Global South. Alongside the development and availability of new technologies to enhance soil fertility, smallholder farmers’ attitudes towards these innovations in specific contexts are key to determining the extent and outcomes of their uptake. A better understanding of these is thus essential to inform measures to increase ISFM practices among smallholder farmers.

IntroductionOilseed pennycress (Thlaspi arvense L.) is an emerging biofuel crop for use in the aviation industry that has potential as a rotational crop in corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] cropping sequences. Ensuring autumn emergence of pennycress after early broadcast seeding is key because this practice may result in uneven spatial distribution due to the small seed size and variable germination, soil contact, and moisture availability. The objective of this research was to evaluate the impact of five seed treatments and enhancements on autumn establishment in two pennycress lines (MN106NS and tt8-t/ARV1) in broadcast seeding compared with no treatment.MethodsTested treatments were (i) gibberellic acid (GA) soak, (ii) fludioxonil fungicide, (iii) pelleting with diatomaceous earth and a commercial binder, (iv) fungicide plus pelleting, or (v) fungicide plus pelleting with GA added to the binder. Seeds were planted at nine sites in four U.S. states to assess establishment (stand counts and percentage canopy cover) in the autumn and spring and seed yield after maturity.ResultsThe MN106NS line had greater plants m−2 and percent green cover with treatments that included GA compared to the control. Line tt8-t/ARV1 had reduced stands when pelleted compared to the untreated, and establishment was unchanged when treated with GA compared to the untreated. Pelleting treatments without GA were not beneficial for stand establishment of either line. Seed yield for MN106NS was 20% greater than the untreated when treated with GA only or pelleted. Seed yield for tt8-t/ARV1 did not increase over the untreated with any treatment and was reduced by 20%–40% when pelleted.DiscussionThese results suggest minimal benefit of seed treatment and pelleting for the tested lines under broadcast seeding, though black-seeded lines may still benefit from GA treatment. Plant establishment and yield were negatively correlated with total precipitation post-planting, suggesting that excessive rainfall post-planting (>60 mm) may impede establishment when broadcast seeded.

An online calculator is available to determine economic optimum nitrogen rate (EONR) for maize (Zea mays L.) production in the USA Corn Belt. For Minnesota, this calculator considers nitrogen (N) fertilizer cost, maize grain price and crop history, and produces a statewide N rate based on maximum economic return to N (MRTN). However, a clear precipitation and temperature gradient, and soil heterogeneity across the state, and recent changes in fertilizer cost and maize grain price require the comparison of EONR from this calculator with results from field study. The objectives of this research were to determine the agronomic and economic benefits of basal and split application of N fertilizer on maize grain yield and yield components and compare EONR from field study with N recommendation from the online calculator. The nitrogen fertilizer rate for the field study ranged from 0 to 224 kg N ha−1, either split or all applied at planting. The results showed that there were no interaction effects of N rate by time or N rate by year on maize grain yield. Maize grain yield had a quadratic response to N rate, and agronomic maximum grain yield peaked at 205 kg N ha−1. The EONR from the field study was 168 kg N ha−1 and it remained stable under a wide range of economic analysis scenarios with net benefit reaching up to 2474 USD ha−1. The N rate from the online calculator at MRTN was 151 kg N ha−1 and this rate may cause N deficiency in maize resulting in a yield penalty compared with the field study results. The field study was performed under specific soil and climatic conditions. Therefore, extensive research under various soil types, agronomic management practices and climatic conditions is warranted to evaluate the online calculator performance and its reliability as a precision tool for N fertilizer management in maize production.

Irrigation is one way of utilizing the land resources to enhance agricultural production. Irrigation crop production is crucial in the present study area due to its arid and semi-arid climatic characteristics. However, little is known about the influence of different cropping and land management practices on soil quality (SQ). This study aimed to determine the effects of different cropping systems and land management practices on variability of SQ indicators in the Central Rift Valley of Ethiopia (CRVE). To this end, 45 disturbed surface (0‒20 cm) and 24 undisturbed (upper 7 cm) soil samples were collected from four adjacent farms: large-scale perennial farms (LSPF), large-scale annual farms (LSAF), smallholder subsistence annual farms (SHAF), and non-cultivated lands (NCL). Soil analyses were made for selected SQ indicators – particle size analysis, bulk density, soil water content, organic matter, pH, total nitrogen, available potassium and phosphorus, exchangeable bases, and cation exchange capacity. One-way analysis of variance (ANOVA) and Pearson correlation coefficient (r) were computed. Key informants’ interview was conducted to substantiate the data obtained from soil laboratory analyses. As the results confirmed, different cropping and land management practices had significant effects on some SQ indicators. Soil organic matter, total nitrogen, available P, and available K declined significantly (P < 0.05) in the soils of LSAF and SHAF. This is attributed to land management-induced problems such as frequent tillage practice of mono-cropping, high level of mechanization, removal of crop residues/above-ground biomass in LSAF, and use of low external inputs and overcultivation without appropriate land management practices in SHAF. However, LSPF practice resulted in the improvement of key SQ indicators, next to NCL. Therefore, LSPF can be an alternative cropping and land management practice to achieve sustainable agricultural production and land management in semi-arid irrigated lands of CRVE and in places with similar environments.

Pennycress (Thlaspi arvense L.) is a new winter annual oilseed crop that can be integrated as a “cash cover crop” in Midwestern USA cropping systems. Relay-cropping pennycress with soybean [Glycine max (L.) Merr.] has been shown as an effective way to produce three crops over 2 years while providing living cover on the agricultural landscape nearly year-round. However, management improvements are needed to optimize pennycress and soybean production in this new system. A 2-year field study was conducted to evaluate three soybean interseeding dates (based on pennycress growth stage) and three soybean cultivars (varied in maturity date) on the overall productivity of this relay system. Interseeding dates were SD1 (rosette stage), SD2 (bolting stage), and SD3 (initial flowering), and soybean cultivars were MG0.2 (early), MG1.1 (standard), and MG1.7 (late). In the second season, relaying soybean reduced pennycress seed yield compared with its monocrop counterpart, but the reduction was lowest (23%) at SD2. Cultivar maturity group impacted soybean seed yields in the relay system, which for MG0.2, MG1.1, and MG1.7 averaged 2,589, 3,196, and 3,445 kg ha−1, respectively. Although there was soybean yield drag associated with relay cropping, the seed yield of the MG1.7 cultivar relay interseeded at SD2 was not significantly different from a monocropped MG1.1 soybean using conventional practice (CP; winter fallow, no pennycress). The results indicate that relay interseeding of longer maturity (MG1.7) soybean for the region at the bolting stage (SD2) of pennycress optimized overall system productivity while keeping the continuous living cover on the agricultural landscape. More research will likely be needed to improve soybean selection and management regionally for this unique relay system.

Abstract Enhancing crop diversification is needed to ensure sustainable food and energy production in the soybean [Glycine max (L.) Merr.] and maize (Zea mays L.) dominated cropping systems of the US Midwest. Relay‐cropping soybean with winter camelina [Camelina sativa (L.) Crantz] is a means to sustainably intensify food and energy production while adding cropping system diversity. However, soybean yields in relay systems tend to be less than a full‐season monocrop. We hypothesized that improved soybean selection and seeding date for relay cropping could minimize this yield gap, thus increasing agricultural land use productivity. A 2‐year field study was conducted to determine the effects of soybean maturity and seeding date (SD) on winter camelina and soybean yields and land use productivity. Three soybean genotypes differing in maturity (MG) were relayed into winter camelina at rosette (SD1), bolting (SD2), and first flowering (SD3) growth stages. The soybean MGs were MG0.2, MG1.1, and MG1.7 representing early, standard, and late maturity, respectively, for the study region. The MG1.1 sown at SD2 was grown as sole crop check using conventional practices (CP). Results demonstrated that SD3 decreased camelina seed yield compared with SD1 and SD2. Soybean yield in the relay system was greatest for the MG1.7 genotype, and averaged across SD1 and SD2, was just 11.6% less than the sole crop CP check. Relaying soybean MG1.7 at SD2 produced 43% greater total (camelina +soybean) oil yield and greatly improved land use efficiency compared with CP. Appropriate soybean genotype selection can enhance winter camelina–soybean relay system productivity and land use efficiency.

Soil quality (SQ) dynamics assessment vis-à-vis land use/land cover (LULC) and elevation variations in Ethiopia is desirable as elevation impact on land use is highly pronounced. This study examined SQ indicators dynamics across LULC and elevation variations. For this, surface soil samples (0−20 cm) were collected from the recognized LULC categories of different elevations in Wanka watershed, northwestern Ethiopian highlands. Both disturbed and undisturbed soil samples that were taken from three adjacent LULC (natural forest, grazing and cultivated lands) and elevation (2238–2300, 2400–2600, and 2700–2800) classes analysed for the selected physico-chemical SQ indicators. Two-way ANOVA, Tukey’s multiple comparison test and SQ deterioration index were computed. The impact of LULC and elevation was found significant on key SQ indicators. In cultivated and grazing lands, soil organic matter (SOM) and soil nutrients like total nitrogen declined significantly (p < 0.01). Conversely, bulk density increased significantly (p < 0.01). The divalent basic cations (Ca2+ and Mg2+), cation exchange capacity and pH significantly (p < 0.01) decreased in upper elevation. Synergetic effect of LULC and elevation variations was found significant (p < 0.01) on SOM, total nitrogen, available phosphorus, water content at field capacity and soil particle distribution (silt and clay). Thus, elevation specific land management strategies that improve these SQ indicators need to be emphasized.

Abstract The need for organic produce is increasing worldwide but weed control remains a critical problem for organic crop production. Three types of weed control practices were evaluated for two organic chickpea (Cicer arietinum L.) varieties at the Western (Corvallis) and Eastern (Sidney) Agricultural Research Centers of Montana State University. Treatments included two chickpea varieties (Black and CDC Orion chickpeas), two seeding rates (standard seeding rate or 1× at 43 seeds m−2 and 50% increase over the standard rate or 1.5×), and two pre‐emergent weed control practices (flame weeding and shallow tillage). Results revealed that Black chickpea was associated with greater stand densities and grain yield with lower weed biomass than CDC Orion. Increasing seeding rate for Black chickpea improved crop density and increased grain yield to the extent of 26% compared with the standard seed rate. Flaming increased chickpea grain yield only at Corvallis in 2016. The combined effects of shallow tillage and increased seeding rates resulted in reduced weed biomass. Shallow tillage can be successfully integrated to improve yields and reduce weed pressure in organic chickpea. However, precaution must be taken for the tillage timing to avoid damage to emerging chickpea seedlings. More research is needed to select chickpea varieties that have improved vigor and are more competitive to weed pressure commonly seen in organically managed fields.

Improved agronomic management strategies are needed to minimize the impact that current maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) production practices have on soil erosion and nutrient losses, especially nitrogen (N). Interseeded cover crops in standing maize and soybean scavenge excess soil N and thus reduce potential N leaching and runoff. The objectives were to determine the impact that pennycress (Thlaspi arvense L.) (PC), winter camelina (Camelina sativa (L.) Crantz) (WC), and winter rye (Secale cereale L.) (WR) cover crops have on soil N, and carbon (C) and N accumulation in cover-crop biomass. The cover crops were interseeded in maize at the R5 growth stage and in soybean at R7 in four replicates over two growing seasons at four locations. Soil and aboveground biomass samples were taken in autumn and spring. Data from the maize and soybean systems were analyzed separately. The results showed that cover crops had no effect on soil NH4+-N under both systems. However, winter rye decreased soil NO3−-N up to 76% compared with no-cover-crop treatment in the soybean system. Pennycress and WC scavenged less soil N than WR. Similarly, N and C accumulation in PC and WC biomass were less than in WR, in part because of their poor growth performance under the interseeding practice. Until PC and WC varieties with improved suitability for interseeding are developed, other agronomic practices may need to be explored for improving N scavenging in maize and soybean cropping systems to reduce nutrient leaching and enhance crop diversification.

Soil organic carbon (SOC) and total nitrogen (TN) stock are key indicators of soil quality in tropical regions; however, their status is often degraded, especially due to massive deforestation in natural forest areas associated with extensive agricultural land use. The aim of this study was to investigate the dynamics of SOC and TN stock in different land-use systems in the Abobo woreda, Western Ethiopia. To analyze their status, 80 disturbed (composite) and 45 undisturbed soil samples were collected from the top 20 cm of soil in five major land-use types: natural forestlands, grasslands, recently developed commercial farmlands, old commercial farmlands, and small-scale cultivated lands. The results showed that SOC stock varied significantly across the different land-use types, with mean stock ranging from 32.23 Mg·ha−1 in recently developed commercial farmlands to 54.54 Mg·ha−1 in natural forestlands. The mean TN stock ranged from 2.54 Mg·ha−1 in recently developed commercial farmlands to 4.63 Mg·ha−1 in natural forestlands. With natural forestlands as a baseline and the duration ranging in age from 15 to 45 years since land-use conversion, the mean annual absolute rates of change in SOC and TN stock loss were 0.49, 1.49, 0.39, and 0.45 Mg·ha−1·yr−1 and 0.05, 0.14, 0.03, and 0.04 Mg·ha−1·yr−1 for grasslands, recently developed commercial farmlands, old commercial farmlands, and small-scale cultivated lands, respectively. The results of this study revealed that soil disturbance during forestland conversion to tillage enhanced the decomposition rate of organic matter in recently developed commercial farmlands. Nevertheless, after agricultural abandonment and vegetation restoration, the SOC and TN stock capacities were enriched in the old commercial farmlands. It is, therefore, important to effectively restore vegetation and implement sustainable land-use management practices. [ABSTRACT FROM AUTHOR]

Since the 1970s, the Government of Ethiopia has implemented villagization, whereby nomadic pastoralist groups are supported to develop (more) sedentary lifestyles and livelihoods. Villagization has been officially promoted to encourage diversification from livestock herding to agricultural cultivation, and to fulfil basic needs through infrastructure and services. From the late 2000s, villagization was reintroduced for arid and semi-arid regions as a strategy for adaptation to climate change, as part of the country's green growth agenda. The aim of this paper is to evaluate to what extent this phase of villagization has contributed to adaptation strategies among pastoral and agro-pastoral communities, based on an empirical analysis of four villagised sites in the Middle Awash Valley using qualitative data collected between 2014 and 2018. Perceptions and experiences of villagization varied across individuals, households, villages, and districts. While villagization has generally delivered infrastructure and services, and offered income diversification to those able to access irrigated agriculture, its implementation has been partial and uneven, and it has reproduced previous problems of resource scarcity while creating new risks and vulnerabilities. We argue that villagization may play a role in some aspects of adaptation, if programmes address the drivers of livelihood change, and embed equity and rights. [ABSTRACT FROM AUTHOR]

PURPOSE: Famines and food shortages are one of the most common long time histories of Ethiopia. Hence, malnutrition has been persisted at alarming raters in the country. Moreover, it is a major cause of morbidity and mortality in Afar National Regional State of Ethiopia. Specifically, in Amibara and Awash Fentale districts. The anthropometric data were presented on height, weight, MUAC, weight/height/Age and Body Mass Index (BMI) of under-five children. METHODS: A cross-sectional descriptive survey was conducted from March 01, 2017 to June 15, 2018. The data was collected by using anthropometric measurement. A multi stage random sampling procedure was applied in order to recruit the required sample size. The data collections were conducted at two selected districts in Afar region by trained interviewers and health care providers. The data were analyzed by using SPSS Version 23. Bivariate analysis between dependent and independent variables was employed. Multivariate analysis was also done to control for possible confounding variable by selecting variable which show statistically significant association (P < 0.05). RESULTS: Out of 410 under five children's anthropometric finding, the majorities (62.7%) of those registered under five children were male and (33.3%) were female. The majority (46.8%) of under five children were less than or equal to 50 cm by their height. Most (54.1%) of under five children were less than or equal to 12.5 cm by their MUAC. It indicated that they were diagnosed with severe malnutrition based on anthropometric measurements. Meanwhile, majority (64%) of under five children were less than 60% their weight/age. Regression analysis result indicated that all of the variables were not significant predictors of BMI for under five children (P > 0.05). Based on ANOVA result, there was significant difference between sex and other predictors (P = 0.031). This finding implies that improvement in food aid and poverty alleviation programs are very important. Based on the finding, it is important to provide high quality and quantity of food. Moreover, less access to assets and health services commonly contributed for malnutrition. Highlighting under five children's malnutrition will help to develop and design future policies and programs in Ethiopia. [ABSTRACT FROM AUTHOR]

BACKGROUND: Drought is a serious issue which might be caused by climate change that could create famine and health problems. Drought reduces air quality, increases fungal infestation, reduces people hand washing, affects mental health, leads to malnutrition by decreasing agricultural production, and increases diseases transmitted by insects. This study aimed to determine and describe community health status through building drought resilience in Ethiopia. METHODS: This review was conducted based on the available peer-reviewed articles that were published from January 2004 to December 2018 Online databases from PubMed, MEDLINE, Scopus, EMBASE and Google Scholar were searched for studies related to the building drought and community health resilience at different regions of Ethiopia that were published in English language. The search was made by using "Emergency disaster", "prevention", "preparedness", "response", "recovery", "drought", "food insecurity", "coping strategies" and "drought health policy" as keywords. RESULTS: Most of the reviewed articles deal with the impact of climate change on the human health in relation to food security. The associated factors of the impact of drought on food security is basically due to lack of irrigation and farmland, the scarcity of water due to the direct effect of drought, flood, severe soil erosion, livestock dispossession, family size of the household and literacy of the households. Various coping strategies were employed by the households to alleviate the high and continued food insecurity problem such as reducing the number and amount of meal, scrounging cash and grain, searching for off-farm and non-farm jobs, getting food aid, vending of livestock, and partake in food for work programs. CONCLUSION: The findings explored components of the coping strategies to the building resilience create fruitful health conditions for the food insecure household. The effect of agricultural support services as reliance's on drought and community health situation was regarded as a positive outcome. Moreover, the means to get adequate food security strategies in all regions of Ethiopia should be designed. Furthermore, future researches are recommended for finding the best building strategies for each region of Ethiopia. [ABSTRACT FROM AUTHOR]

Indoor radiation is a concern for people living in buildings constructed from materials with high emission of radionuclides. In this study, radiation rate measurements of 39 rooms in nine buildings of three different age groups at three locations were made using Electronic Personal Dosimeter (EPD). The measurements included both interiors and exteriors of the rooms. Interior measurements were made in two perpendicular directions from two adjacent walls at distance interval of 0.5 m. The EPD measurement revealed a decrease in the magnitude of the radiation as the days of measurement progressed, and that necessitated the need of correction factors, which were evaluated using background radiation rates of each location separately. All measured radiation rates were then corrected using the respective correction factors. The results obtained are summarized as follows. Background radiation doses at HU campus and Harar and Dire Dawa towns, averaged over the measurement days is, 4.1, 2.8 and 2.4 mSv/y, respectively. These values reflect effective external doses of 0.82, 0.55 and 0.47 mSv/y, respectively, for the three locations. Dire Dawa old building differed from all the other buildings of the three locations and it exhibited the highest interior radiation of average dose of 0.027±0.011 mSv/y above the background radiation. There were no significant differences between the new and the intermediate buildings of the three locations. When averaged out, irrespective of building ages of each location, HU buildings showed average dose of 0.004±0.004 mSv/y, Harar, -0.008±0.006 mSv/y and Dire Dawa, 0.009±0.008 mSv/y. No difference in radiation rates were observed between the two directions but radiation rates slightly increased from walls to the centers of rooms up to a certain point. Radiation rates of the interior and exterior of each room did not show a significant difference. Though differences were observed among buildings of the three different ages, the differences were not uniform at the three locations. The doses from all the rooms were within the limit set by IAEA for indoor radiation. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence, level of severity of potential drug-drug interactions (PDDIs) and the associated factors for PDDIs in hospitalized pediatric patients of Gondar University Hospital. Methods: A retrospective cross-sectional study was conducted for a period of 3 months from March to May 2014 in pediatric wards of Gondar University Hospital. Systematic random sampling technique was used to select charts from all pediatric patients' charts with every 7th interval to get sample size of 384. Univariate and multivariate analysis were performed to compute crude odds ratio and adjusted odds ratio respectively. Statistical significance was set at P value < 0.05. Results: A total of 176 (45.8%) patients had at least one PDDI. A total of 393 PDDIs, which were comprised of 283 types of interacting combinations, were identified. Of the total of 393 PDDIs, most were of moderate severity [201 (51%)] followed by minor [152 (39%)] and major severity [40 (10%)]. The most common interacting pairs of major severity were gentamicin + furosemide (6), cotrimoxazole + methotrexate (4) and phenytoin + artemether (4). The occurrence of PDDIs was significantly associated with age and polypharmacy. Conclusions: The study showed that most of the interactions had moderate severity followed by minor severity. Age and polypharmacy were found to show statistically significant association with the occurrence of PDDIs. Due to sensitive nature of pediatrics population, close monitoring is recommended for the detection and management of PDDIs to prevent its negative consequences. [ABSTRACT FROM AUTHOR]

Land use/land cover changes in a lake drainage basin reflect changes in the magnitude of the water balance components and rate of sediment deposition in a lake as a reflection of the fundamental linkage between what happens in a lake considered against what is happening in the drainage basin of the lake. The objective of this study was to quantify the spatio-temporal land cover/land use changes across the Lake Hayq closed drainage basin in north-east Ethiopia over a 50-years period, using multitemporal remote sensing and geospatial data. Two historical occasions of aerial photographs (1957 and 1986) and one satellite image (2007) were examined with image analysis tools: Leica Photogrammetric Suite ( LPS 9.2) Project Manager, ArcGIS10.0, and ERDAS EMAGINE 9.2. Seven aerial coverage of land use/land cover categories were identified and mapped for the past three historical times. The results indicated that farmlands/settlements and shrublands/degraded lands increased by 43.1% and 136.9%, at an annual rate of 27.4 and 13.5 ha year−1, respectively, between 1957 and 2007. In contrast, bushlands, grasslands, forestlands and lake surface area were diminished by 68.8%, 62.7%, 90.5% and 7.6%, at a rate of 24.0, 7.6, 6.1 and 3.7 ha year−1, respectively, over the past five decades. The basin had undergone significant transformation in land use/land cover over the past half century, affecting the lake's biophysical stability by accelerating soil erosion in the basin, sediment accumulation, and a reduced quantity and quality of cumulative stream flow into the lake. [ABSTRACT FROM AUTHOR]

This study analysed long-term land use/land cover (LULC) dynamics and their underlying causes and implications for land resources management in a dryland watershed of Hirmi and its adjacent agro-ecosystem, northern highlands of Ethiopia. Two sets of aerial photographs (1964 and 1994) and 2006 Spot 5 satellite images were utilised in the study. These derived data were complemented with the help of focus group discussions and personal interview methods. The study identified five LULC types: cultivated and rural settlement, forest, grassland, town and a small artificial pond. Expansions of cultivated and rural settlement and forestland use/land cover and a reduction of grassland and shrubland use/cover types were observed throughout the analysis period. Over the 42-year period, cultivated and rural settlement land increased by 24.6%. Grassland declined sharply from 20% in 1964 to 11.3% in 2006. The area under forest cover expanded from 0.9% in 1964 to 1.8% in 2006. The town of Indaselassie increased at a rate of 8.95 hectare (8.1%) per annum. An artificial pond covering 6 ha emerged between 1994 and 2006. Combinations of proximate and underlying causes such as poverty, demographic pressure, institutional and policy factors have influenced LULC dynamics in the Hirmi watershed and the adjacent agro-ecosystem. The LULC dynamics resulted in the degradation of land resources. There is a need to control the immediate causes of LULC dynamics by limiting cropland expansion via increasing land productivity and devising strategies to regulate urban land expansion. Long range strategies such as methods of easing population growth and ways of alleviating rural poverty need to be devised to bring about sustainable land resources management practices in the study site. [ABSTRACT FROM AUTHOR]

This study aimed to determine the spatial variation of topsoil properties as influenced by slope aspects and vegetation types. Three vegetation types and two slope aspects were considered. Disturbed and undisturbed samples were taken from the top soils. A two-way analysis of variance was used to test significant mean differences (α = 0.05). Results showed that contents of bulk density, total porosity, organic matter and exchangeable magnesium were significantly different with changes in slope aspect ( P < 0.05). Textural classes, organic matter, available phosphorus, carbon-to-nitrogen ratio, cation-exchange capacity, per cent base saturation and exchangeable bases demonstrated significant variation among vegetation types ( P < 0.05). The south-facing aspect and the grass vegetation showed higher bulk density but lower organic matter and total porosity. As a remedy for the identified problems, there is a need to undertake plantation of indigenous trees. [ABSTRACT FROM AUTHOR]

The generation of scientific information for improved understating of the physical dynamics of a lake is fundamental for guiding lake stakeholders and managers at the local level to implement best management practices and help design effective management strategies and policies at higher levels. Multitemporal bathymetric information on lakes is very important in hydrology and sediment studies to more clearly indicate environmental changes and to understand the effects of land processes on the hydrology of lakes. Accordingly, the purpose of this study was to map bathymetric charts of Lake Hayq in Ethiopia and to derive morphometric parameters, including depth, volume, area, width and length, and to plot curves illustrating the relationships between these parameters. The bathymetric survey was carried out using a combination of a SonarLite Portable Echo Sounder and Global Positioning System ( GPS) to generate three-dimensional ( XYZ) hydrographic data. Surfer 8.01 and Arc GIS 9.3 software program were used for surface, gridding and morphometric analyses. Comparison of the results of this study with a previous study conducted in 1941 indicated the lake has experienced changes in depth and surface area. To reduce the negative impacts of human-induced activities on the ecohydrology of the lake, and to maintain its ecological integrity, appropriate and integrated lake management practices must be adopted. This will necessitate policy formulation, active lake basin stakeholder involvement and implementation of basin-wide lake management to ensure sustainable use of the lake and its basin resources. [ABSTRACT FROM AUTHOR]