Lessons from upstream soil conservation measures to mitigate soil erosion and its impact on upstream and downstream users of the Nile River

A study was conducted to evaluate the effects of soil bunds stabilized with vetiver grass (V. zizanioides) and tree lucerne (C. palmensis) on selected soil physical and chemical properties, bund height, inter-terrace slope and barley (Hordeum vulgare L.) yield in Absela site, Banja Shikudad District, Awi administrative Zone of the Amhara National Regional State (ANRS) located in the Blue Nile Basin. The experiment had five treatments that included non-conserved land (control), a 9-year old soil bund stabilized with tree lucerne, a 9-year old soil bund stabilized with vetiver grass, a 9-year old sole soil bund, and a 6-year old soil bund stabilized with tree lucerne. Data were analyzed using one-way analysis of variance (ANOVA) and mean values for the treatments were separated using the Duncan Multiple Range Test. Results of the experiment indicated that organic carbon (OC), total nitrogen (N), bulk density, infiltration rate, bund height, and inter-terrace slope are significantly (p?0.05) affected by soil conservation measures. The non-conserved fields had significantly lower OC, total N, and infiltration rate; whereas higher bulk density as compared to the conserved fields with different conservation measures. However, no significant differences in bulk density were observed among the conservation methods. The field treated with 9-year old soil bund stabilized with tree lucerne or sole soil bund had significantly higher OC content than all other treatments. Fields having 6-year old soil bunds had lower OC and total N when compared to fields having 9-year old soil bunds irrespective of their method of stabilization. Fields with soil bunds stabilized with vetiver grass had the highest bund height and the lowest inter-terrace slope than fields with the remaining conservation measures. Barley grain and straw yields were significantly (P<0.05) greater in both the soil accumulation and loss zones of the conserved fields than the non-conserved (control) ones. In the accumulation zone, fields with the 9-year old soil bund stabilized with tree lucerne and those with the 9-year old sole soil bund gave higher grain yields (1878.5 kg ha-1 and 1712.5 kg ha-1, respectively) than fields having 9-year old soil bund stabilized with vetiver grass (1187 kg ha-1) and 6-year old soil bund stabilized with tree lucerne (1284.25 kg ha-1). When we compare the accumulation and the loss zones, the average grain yield obtained from the accumulation zones (averaged over all the Lessons from Upstream Soil Conservation Measures to Mitigate Soil Erosion and its Impact on Upstream and Downstream Users of the Nile River.Length: pp.170-183ErosionLand degradationSoil conservationBundsWater conservationSoil properties

Estimation of Economic Returns to Soil and Water Conservation Research – An Ex Ante Analysis

The economic returns to investment made in soil and water conservation research have been analyzed. Technologies such as conservation furrow, residue incorporation have been found to be economically viable under farmers’ conditions. The study has covered four locations, viz. Agra and Varanasi in Uttar Pradesh, Kota in Rajasthan and Jabalpur in Madhya Pradesh. The economic surplus analysis has revealed that when adopted on a large scale, soil and water conservation technologies generate significant economic surplus as reflected in high NPV and BC ratio. The share of producer surplus has been found to be higher in the total economic surplus generated from technology adoption. Thus, investments in generation and transfer of soil and water conservation technologies have been found be justified in terms of economic benefits. However, various constraints that hamper adoption of these technologies are to be addressed so that the potential benefits could be realized by both farmer and consumer.Agricultural and Food Policy,

CROP INSURANCE, GOVERNMENT AGRICULTURAL POLICIES, AND SOIL EROSION

This paper investigates the relationship between government agricultural programs and soil erosion. Using county-level data from the years 1992 and 1997, we estimate a model of water-induced (i.e., sheet and rill) soil erosion and crop insurance participation for counties where corn, soybean, and winter wheat account for at least 90% of total planted acreage. This includes most of the areas that have exhibited the highest historical levels of sheet and rill erosion. We find that crop insurance participation and conservation payments are significantly associated with county average soil erosion levels. In particular, corn insurance participation exhibits a positive impact on soil erosion, while wheat insurance participation exhibits a negative impact. After controlling for differences in soil erodibility, counties that receive higher conservation payments exhibit lower levels of soil erosion. We also find that government price and income support program payments (e.g., target price-based/loan deficiency payments and AMTA payments) exhibit no statistically significant association with our soil erosion measure.Environmental Economics and Policy,

Estimating Soil Loss Rates For Soil Conservation Planning in Borena Woreda Of South Wollo Highlands of Ethiopia: The Case from the Legemara Watershed

The rate of soil erosion is pervasive in the highlands of Ethiopia. Soil conservation is thus crucial in these areas to tackle the prevailing soil erosion. This area is mainly in the steeper slope banks of tributaries where steep lands are cultivated or overgrazed. The objective of this study is to estimate the rate of soil loss in Legemara watershed in Borena Woreda of South Wollo Administrative Zone in the Amhara Regional State. The study also recommends possible ways of curbing the problem.The study uses the Revised Universal Soil Loss Equation (RUSLE), integrated with satellite remote sensing and the Geographical Information System (GIS) as useful tools for conservation planning. Monthly precipitation, a soil map, a 30m-digital-elevation model, a land-cover map, land-use types and slope-length steepness were used to determine the RUSLE values. Based on the level of soil erosion rates, the study area was divided into five priority categories for conservation interventions. The results show that, 2,344.57 ha (42.97 %) of the total area and 130,102.35 tons ha-1yr-1 (77.19 %) of the total soil loss have ranges of the erosion severity classes of very severe and severe, in which case, conservation priorities of first and second order are suggested. Moreover, the total soil loss in the study area was168, 521 metric tons per year from 5456.5 ha, and the average annual soil loss for the entire watershed was estimated at 30.88 metric tons ha-1yr-1.Keywords: Soil Erosion; RUSLE; GIS; Conservation; Watershed; Ethiopi

MEETING THE KYOTO TARGET THROUGH CONSERVATION TILLAGE AND ITS IMPLICATION FOR NATURAL CAPITAL MAINTENANCE, PRODUCTION EFFICIENCY, AND SUSTAINABILITY

According to Article 3.4 of the Kyoto Protocol, agricultural soil could be used as a sink for carbon sequestration and hence it may provide an alternative venue to sequester the greenhouse gas emission. US plans to reduce the carbon emission amount by seven percent below the 1990 level within the target date of 2008-2012. The major approaches to achieve the goal targeted by Kyoto Protocol in US are through fossil fuel tax and increasing forest area by afforestation. This means fossil fuel price will increase which will have a direct impact to conventional tillage cost. As a result farmers would be motivated to use less machinery operation in farming and hence may use conservation tillage in farming practices. Rather than cause and effect relationship created by fuel price increase, conservation tillage itself has been considered as a method suggested to increase carbon sequestration. We analyze the economic and environmental roles of conservation tillage in carbon sequestration. The use of conservation tillage helps to sequester carbon in the form of soil organic matter. We examined the potential of conservation tillage in sequestering carbon and its role in increasing soil natural capital and thus the productivity of soil. We then used the concept of production efficiency to calculate the benefits of soil carbon sequestration using sustainability criteria. The detail of carbon sequestration and soil natural capital buildup were demonstrated using conservation tillage practiced in cotton production in Georgia. Four systems of conservation tillage encompassing both chemical and organic source of plant nutrients were compared for their capacity to sequester carbon. Organic matter buildups were faster in a system with conservation tillage and organic sources of nutrient compared to conventional tillage. Result indicated that in a system with a slow buildup of natural capital, production efficiency was not significant. This has resulted the system to be unprofitable in the short run and unsustainable in the long run. The system with a high amount of organic matter increases the production efficiency of applied inputs and also plays an important role in substituting chemical fertilizers. Alternative tillage management systems were evaluated for their sustainability using total factor productivity. It was found that conservation tillage meets criteria of sustainability more often than the management system containing conventional tillage. Conservation tillage was found to be the best alternative not only to sequester carbon but also developing natural capital-based sustainable system.Kyoto protocol, Carbon sequestration, Natural capital, Production efficiency, Sustainability, Environmental Economics and Policy, Productivity Analysis,

The Effects of Integrated Soil Conservation Practices on Soil Physico-Chemical Properties: The Case of Menesibu District, West Ethiopia

The study was conducted in Ethiopia, in Oromia Regional State, West Wollega Zone, Menesibu district to evaluate the effect of integrated soil conservation practices on soil physical and chemical properties. The land treated by integrated soil conservation practices were compared with land untreated. These were again evaluated across three slope gradients and two soil depths. The slope gradients were; gentle slope (3-10%), moderate slope (10-25%) and steep slope (&gt;25%). The study adopted a Randomized Complete Block Design (RCBD) with split-split plot layout. A total of 36 soil samples were collected from the top 0-20 cm and 20-40cm soil depths, which were replicated three times and the selected physical and chemical properties were analyzed in the laboratory. The results of the study showed that soil bulk density (BD), soil pH, electrical conductivity (EC), soil organic carbon (SOC), total nitrogen (N) available phosphorus and potassium (Av-P &amp;Av-K), cation exchange capacity (CEC) and exchangeable cations (Na+, K+, Ca2+, Mg2+) were significantly different (P &lt; 0.05), with the land treated by soil conservation practices showing better conditions than the untreated control under the three slope gradients and the two soil depths. No significant difference was observed in terms of soil texture between the conserved and un-conserved lands but there were significant differences among the slope gradient and the soil depths. The carbon to nitrogen ratio (C/N) was also not significantly different between the two land types (conserved and un-conserved land), slope gradients and soil depths. Keywords: Soil conservation practices, conserved land, un-conserved land, soil physical properties, soil chemical propertie

Effects of Soil Conservation Practices on Soil Properties in a Cotton and Soybean System in West Tennessee

Integration of conservation agriculture practices can provide benefits to crop production. The number of studies focusing on conservation agriculture practices’ effects on sustainable agriculture and environment have increased. In this study, two different experimental field were focused on. In the first one, we evaluated different tillage systems, cover crops and nitrogen fertilizer rates impact on soil properties which are soil total organic carbon (TOC), dissolved organic carbon (DOC), permanganate oxidizable carbon (POXC), total nitrogen (TN) and wet aggregate stability (WAS) under continuous cotton production. The results showed that cover crops were statistically significant in increasing all the properties measured. No-till only increased WAS and TOC compared to conventional tillage among the soil properties. Overall conservation practices had potential for enhancing soil properties on a long-term experiment. in the second study, effect of different rate of biochar on hydro-physical properties of fluvial deposits was evaluated. In this study, soil organic carbon (TOC), total nitrogen (TN) infiltration, bulk density, saturated hydraulic conductivity Ksat and moisture content were analyzed. The results indicated that Biochar rate over 82 t/ha has increased total organic carbon at both depths (0-5/5-15cm) while it has decreased bulk density significantly at 0-5 and 5-15 cm. 20.5, 41 and 82 t/ha rates of biochar showed higher moisture content compared to the other treatments. Except the highest rate of biochar, the other treatments showed no effect on total nitrogen at 0-5 cm. these are two studies evaluating conservation practices impacts on soil properties under different main crops. More similar studies are needed to help farmers to make decision of selecting the most proper practice for their production systems

SOIL CONSERVATION TECHNIQUES AND PRODUCTIVITY OF ARABLE CROP FARMERS IN KOGI STATE, NIGERIA

The study examined soil conservation techniques and its effect on productivity of arable crop farmers in Kogi state, Nigeria. Data were collected from 184 farmers using three stage sampling technique.&nbsp; Data analyses were carried out using descriptive statistics, Total Factor Productivity (TFP) and regression analysis. Result shows that the soil conservation technique prevalent in the area was application of inorganic fertilizer. About 36.4% of the sampled household heads have productivity value above average across all the soil conservation categories (productive). Result also reveals that age (-1.801), household size (-0.310) and access to credit (-0.056) impacted arable crop farmers negatively while alley cropping (0.357), crop rotation (0.380), application of inorganic fertilizer (0.503), mulching (0.560) and organic manure (0.373) positively impacted arable farmers’ productivity.&nbsp; The study concludes that soil conservation techniques are productivity enhancer. Promoting sustainable conservation techniques that are farm or farmer specific is recommended. &nbsp; &nbsp

Construction of Soil Conservation Structures for improvement of crops and soil productivity in the Southern Ethiopia

Soil erosion is one of the major agricultural problems in the highlands of Ethiopia. Deforestation, overgrazing, and cultivation of slopes not suited to agriculture together with the farming practice that do not include conservation measures are the major causes for soil erosion in much of Ethiopia's highland areas. Degraded soils are also the major constraints to agricultural production and food security in the Southern Ethiopian highlands. A study was conducted on watershed that covers 544 ha at Gununo area of Wolaita Zone in the Southern Ethiopia with the objective of conserving soils by constructing soil conservation measures. The soil conservation measures were implemented fully with the participation of farmers. A survey was conducted and soil erosion and fertility decline were identified as top priority problems of the watershed. Then discussion was made among PAs leaders, researchers, and the community about the solution and soil conservation measures were constructed and bund stabilizers (Elephant grasses) were planted by collective action. Continuous participatory monitoring and evaluation was made for maintenance of the structure, improvement of soil fertility, and observation of its effect on crop yields. Soil and crop data were collected after implementation of conservation measures and compared with the baseline information. A total of 9965 m soil conservation structures were constructed, out of which 66.9% and 30.5% are Fanya-juu and soil bund, respectively. The soil conservation measures adapted well to the local conditions and protected the soil from being eroded. The colour of the soil was changed to black and organic matter content was increased. Yield was increased by 22 % on some farms and 15 fold on other farms within one year of bund/fanya-juu construction and by &gt;50 % after 3 years with similar farming practices. The land that could not grow any crop yielded 800 kg/ha of haricot bean after implementation of soil conservation measure. The purchasing power of the farmers increased after they conserved their soil. In conclusion, construction of soil conservation measures in the degraded highlands and stabilizing with multipurpose plant species is very important to conserve the soil and increase crops yields. Key words: Soil conservation measures, Degraded soils, Soil erosio

Farmers’ Perception of the Impact of Land Degradation and Soil and Water Conservation Measures in West Harerghe Zone of Oromia National Regional State, Ethiopia.

This study was conducted to assess the farmers’ perception of the impact of land degradation and its’ conservation measures on crop productivity and income in West Harerghe Zone of Oromia National Regional State, Ethiopia. The study was based on the data obtained from 398 sample households using pre-tested structured interview schedule. The data were analyzed using simple descriptive statistics with the appropriate statistical tests. The result of the analysis revealed that out of the total sampled households, 82.7 percent were perceptive about the problem of soil erosion and majority of these households (54.5 percent) perceived erosion on their land as severe. The perceived fertility decline on their farm was, 28.1 percent less severe, 57.9 percent sever and 13.9 percent very severe. More than 55 percent of sampled respondents also believe that the impact of land degradation on yield/productivity decline of their lands was severe. Likewise, majority (98.9 percent) of the total households were perceptive about the impact of soil and water conservation in improving soil fertility and yield/production. However, significant proportion farmers who perceived the impact of land degradation and the conservation measures on crop productivity and income were using traditional measures. Therefore, to encourage adoption of improved conservation measures extension, institutional support programs and projects which promote soil and water conservation technologies should have strategies which focus on enhancing the willingness of farm households. Keywords: Land degradation, soil and water conservation, perception, Ethiopia