Academic literature on the topic 'Water and soil conservation'

A simple water balance model was applied to a micro-catchment water harvesting system for a semi-arid area in the North-Eastern part of Jordan. Two Negarim micro-catchment water harvesting systems were built at Al-Khanasri research station. A Randomized complete block design (RCBD) in factorial combination was used with six treatments and three replicates. Each plot was divided into two parts; a runoff area, and a run-on area. Two different treatments were used for the catchment area, these were: compacted (T1) and Natural treatments (T2). Three treatments were used for the run-on area, these were: disturbed (S1), stones (S2), and crop residue mulch (S3). Soil water content was measured over a depth of 0-1 m during the seasons 96-97 in these micro-catchments. In this model; daily rainfall, runoff, and evaporation were used. Runoff was calculated by the curve number method; evaporation was calculated by the Penman equation, the Priestley and Taylor method and the Class A pan approach. The least squares method was used for optimizing model parameters. The performance of the model was assessed by different criteria, such as root mean square error, relative root mean square error, coefficient of determination and the Nash-Sutcliffe efficiency method. The performance of the micro-catchments system was also evaluated. Results showed that with limited but reliable hydrological data good agreement between predicted and observed values could be obtained. The ratio of water storage in a one meter soil depth to the rainfall falling on each catchment indicated that T1S2 and T1S3 have the highest values in size1 plots while T2S1 and T2S2 have the highest values in size 2 plots. Modelling results showed that for all the size 1 plots, the required ratio of the cultivated to catchment area, (C/CA), required to ensure sufficient harvested water, was less than the actual ratio used in the experimental design. For the size 2 plots this was only true for the T1 treatments. Consequently for the majority of plot sizes and treatments, the results showed that a smaller catchment area is capable of providing sufficient harvested water to meet crop growth requirements. The experimental ratio was based on a typical yearly design rainfall for the region having either a 50% or 67% probability of occurrence. Results also indicated that using stones and crop residue as mulch on the soil surface in the cultivated area was effective in decreasing the evaporation rate. S3 was more efficient than S2 as it stored more water due to the higher infiltration rate (12.4 cm/hr) when compared to S2 (4.1 cm/hr).

Agriculture has a direct impact on the soil environment, altering soil properties, surface characteristics and erosion risk. This has led to a move away from conventional tillage to the adoption of conservation practices, aiming to minimise soil disturbance and reduce erosion. The effectiveness of this has been shown in studies from the USA, but equivalent research in Europe is limited. The present study investigated losses of soil, water, nutrients and carbon from different tillage regimes. Two UK sites were used – Loddington (Leicestershire, on heavy clay) and Tivington (Somerset on sandy clay loam). Three cultivations were applied - conventional (deep, inversion ploughing), and two forms of conservation tillage - SOWAP (non-inversion, shallow tillage), and Farmer Preference (non-inversion, deep tillage). Treatment effects were investigated at three spatial scales, ranging from field based erosion plots (0.05 ha), to micro-plots (1.5 m2), to soil aggregate tests. Results from 2004 to 2006 showed that adoption of conservation tillage did not consistently reduce losses of soil, water, nutrient and carbon, due to high temporal variability. Notable differences were found between sites. Runoff coefficients ranged from 0.39-0.46% at Loddington, and 2.43-3.82% at Tivington. Soil losses at Loddington were below 2 t ha-1 y-1, but higher at Tivington (3.47 t ha-1 y-1). Conservation tillage led to notable changes in soil properties and surface characteristics, including a decrease in bulk density and increases in organic matter, micro-topography and residue cover. Absolute values of erosion from small scale investigations could not be extrapolated directly to field scale results. Relative treatment ranks gave better comparisons, although results were not consistent for all small scale methods, due to high levels of variability. Caution should be used when extrapolating between spatial scales. Further work is required to understand the links between temporal and spatial fluctuations in soil, surface and rainfall characteristics and erosion processes.

Land degradation resulting largely from the environmentally unsustainable agricultural practices of smallholder farmers is a serious problem in Ghana. It is most serious in northern Ghana, where in spite of past efforts to solve it, persists because farmers' adoption of soil and water conservation technologies has not been encouraging. Farmers' inability to adopt soil and water conservation measures is mainly as a result of constraints resulting from market failures which lead to externalities like degradation. In the presence of externalities, government intervention is justified, and payment for environmental services, whereby incentive payments are made to resource managers, is one such intervention. The current study uses the choice experiment and contingent valuation methods to estimate farmers' WTA for soil and water conservation technologies, specifically soil and stone bunds, and examine the effect of collective action and other factors on farm households' willingness-to-accept. Based on data collected from 305 smallholder farm households in northern Ghana, and using the Bayesian approach, the mixed logit and interval-data probit models were employed to analyze choice experiment and contingent valuation data respectively. Results from both the choice experiment and the contingent valuation methods revealed that farmers like collective action and are prepared to receive less when they act collectively. From the choice experiment, farmers were willing to accept ¢49.40/acre (or ¢125.30/hectare) less in order to act collectively under a compensation scheme for the adoption of SWC technologies. Farmers were willing to accept ¢182.00/acre (¢455.00/hectare) to adopt a SWC technology in order to maintain landscape quality and ¢66.20/acre (¢165.50/hectare) to improve landscape quality. Results from the contingent valuation revealed that farm households would accept from ¢913.46 - 922.08/hectare for stone bund and ¢705.34-714.92/hectare for soil bund. Farmers belonging to farmers' groups were willing to accept from ¢23.55 - 62.54/hectare less than non-group members depending on the technology and type of participation. Willingness of farm households to accept compensation were positively correlated with education, wealth status, farm households with adequate labour supply, the severity of erosion of their farms, and whether the household has already adopted either stone or soil bunds. Age, farm size, and previous participation in soil and water conservation projects are some variables found to be negatively correlated to willingness-to-accept. It is recommended that collective action/contracting be designed into payment schemes to reduce their transaction costs to make them more successful.

The studyâ s purpose was to determine the job satisfaction level of Virginia Soil and Water Conservation District (SWCD) employees during fiscal year 2007-2008. Employee characteristics were identified; three measures of job satisfaction were attained (intrinsic, extrinsic, general satisfaction); and satisfaction levels on 12 specific job aspects were determined. The relationship between job satisfaction and four independent variables (age, gender, education level, primary job responsibility) was assessed. The instrument consisted of an employee characteristics survey, the Minnesota Satisfaction Questionnaire (MSQ) 1977 Short-Form, derived from the MSQ 1967 Long-Form (Weiss, Dawis, England, & Lofquist, 1967), and a modified 2002 Virginia Association of Soil and Water Conservation Districts (VASWCD) survey. Descriptive research statistics were utilized. A total of 185 employees participated, which was an 80% response rate. The majority of employees were characterized as: non-Hispanic, white, female, average age 41 years, married with no children 18 and under living in the home, bachelorâ s degree, average tenure of 6.52 years, full-time, permanent position, average hourly wage of $14.45 and annual salary of $36,373.54, primary job responsibility â technical.â The MSQ found respondents generally and intrinsically satisfied. Greater satisfaction was expressed for variety and social services. Overall respondents were undecided about extrinsic job aspects. Advancement was an area of dissatisfaction. The modified VASWCD survey found respondents satisfied overall. Respondents were â very satisfiedâ with work schedule, type of work, and board relationships. Employees were less satisfied with health insurance benefits, new employee orientation, and compensation. They were â dissatisfiedâ with career advancement opportunities and life insurance. Differences in total intrinsic, extrinsic, and general job satisfaction, as measured by the MSQ, based on the independent variables were determined. A one-way ANOVA and Tukeyâ s post-hoc test were utilized. Since the population of this study violated Leveneâ s Test of Homogeneity, the ANOVA could not be performed for age and intrinsic and general job satisfaction. The ANOVA was performed for all other variables. There was not a significant difference in extrinsic satisfaction among respondents of the various age groups. There were no significant differences in intrinsic, extrinsic, or general job satisfaction for the variables of gender, education level, or primary job responsibility.<br>Ph. D.

Doctor of Philosophy<br>Environmental Design and Planning<br>Timothy D. Keane<br>Kenya has been adversely affected by soil erosion due to population growth, changes in land use and land cover, and unsustainable agricultural practices. Issues related to land degradation cost the Kenyan government approximately $390 million or 3 percent of the country’s GDP yearly (Government of Kenya, 2013). Despite extensive land degradation, many attempts to encourage the use of soil and water conservation (SWC) practices have been unsuccessful. The study focuses on Merigi Ward, Kenya. Merigi Ward lies within the Mara River Basin (MRB), an ecologically and economically important river basin that has experienced extensive erosion problems. Increased agricultural activities driven by population growth in the area and changes in land use and land cover have degraded the landscape. SWC practices are greatly needed to mitigate the effects of erosion and conserve the natural resources within the MRB. Past studies suggest that social capital may increase the adoption of SWC practices (Knowler & Bradshaw, 2007; Nyangena, 2008). This study defines social capital as the groups and networks, trust and reciprocity, formal and informal rules, and information that informs the interactions among persons that lead to collective action. Twenty-five smallholder farmers within Merigi Ward were interviewed and the relationship between the adoption of SWC practices and social capital was explored through a qualitative analysis. Additionally, the MRB is home to the Mau Mara Serengeti Sustainable Water Initiative (MaMaSe). The MaMaSe initiative is a public private partnership (P3) with the goal to promote sustainable water use, economic growth, and environmental conservation within the basin. The effect the MaMaSe initiative had on the level of social capital amongst the study participants was also investigated. Findings suggest that social capital is an important aspect of SWC adoption in Merigi Ward. Groups and networks provide farmers with implementation support and information. Particularly, the local farmers’ cooperative provides farmers with implementation assistance and links (bridging capital) to experts at the MaMaSe initiative and the Ministry of Agriculture. Strong bonding capital works in the favor of this community allowing for high levels of trust. Thus, farmers collaborate to help one another implement practices and exchange information, materials, and experiences. In general, social capital has helped facilitate better environmental conservation awareness and the use of SWC practices. The largest impact the MaMaSe initiative had on the community’s social capital was expanding networks (particularly bridging and linking capital) and providing in depth information and guidelines for SWC practice use. The P3 has also helped the farmers integrate environmental conservation into their daily lives and has helped promote a shared understanding of the importance of conservation. The findings of this study will help environmental conservation professionals understand how to use social capital to strengthen natural resource management.