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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

The long-term effects of farming practices on soil quality, as influenced by farmer attitude and farm characteristics

Boehm, Marie Margaret 01 January 1996 (has links)
Several farming systems, in a region of the Dark Brown soil zone west of Saskatoon, were investigated to identify farming practices that are soil-conserving, or soil-degrading, by measuring their effects on soil quality. The study identified soil properties that are practical and measurable indicators of soil quality, and factors that influence farmers adoption of soil-conserving farming practices. On coarse-loamy to sandy-textured, glaciolacustrine soils, farming systems with long rotations and adequate fertilizer inputs or permanent cover, were associated with a higher quality of soils than tillage-intensive crop-fallow systems. Better soil quality was attributed to the larger addition of crop residues, enabling long-rotation soils to maintain a relatively large pool of mineralizable C, N, and P, and a large microbial biomass. The larger microbial biomass was an indicator of the improved quality of continuously cropped soils as a habitat for microorganisms, and their increased ability to cycle nutrients and C. Other indicators of improved soil quality were increased soil thickness, organic C content, infiltration rate, and aggregation, and decreased bulk density and salinity. Slightly lower A horizon pH was the only negative indicator of quality associated with the continuously cropped soils. The ability of farmers to adapt the longer-rotation systems was constrained by capital and labour limitations, management skills or lifestyle choices. Farmers with limited capital were less willing to invest in the inputs required to continuously crop, because they perceived an increase in the risk of crop failure in that system. Farmers with a large land base, or with off-farm employment, may not have the time or labour to seed and harvest all of their land every year. Among the study farms, the farmers who were best able to adopt continuous cropping systems were those involved in multifamily, mixed farms. There were less labour and capital limitation to continuous cropping on multifamily farms. On mixed farms, where income was derived from both livestock and grains, the risk of reduced grain yield was less serious. Appropriate use of low quality, erodible soils was often an important consideration of farmers who raised cattle.
122

An assessment of sustainable farming systems in Saskatchewan

Maqbool, Muhammad Asim 01 January 1999 (has links)
Farming systems are characterized by many attributes. In order to evaluate their overall sustainability, it is necessary to consider all relevant attributes together. This study uses a multiattribute utility model (MAUM) to compare two tillage technologies (conventional tillage versus zero tillage) to draw an inference about their sustainability. On the basis of five cropping systems, two soil landscapes and two tillage technologies, twenty large size farms are used to represent different range of farms in Saskatchewan. A bio-economic simulator is used to estimate stochastic values of the attributes characterizing these farming systems. The data for bio-economic simulator are obtained from Erosion Productivity Impact Calculator (EPIC) and Top Management Farm Business Simulator (TMFBS) models. The MAUM, based on the preferences of the individuals from two groups (Producers and Agrologists), is used to identify the preferred farming systems. Based on the simulated attribute values and their desirability, conventional tillage systems are preferred in the Brown soil zone. In the Dark Brown and the Black soil zones, the results are mixed. In the Gray soil zone, the zero tillage systems are preferred.
123

Influence of grass hedges on soil hydraulic properties, runoff and soil erosion in a small watershed /

Rachman, Achmad, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
124

Influence of grass hedges on soil hydraulic properties, runoff and soil erosion in a small watershed

Rachman, Achmad, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
125

Soil conservation, land use and property rights in northern Ethiopia : understanding environmental change in smallholder farming systems /

Beyene, Atakilte, January 2003 (has links)
Diss. Uppsala : Sveriges lantbruksuniv., 2003.
126

A policy implementation analysis of soil conservation practices by shallholder farmers in the Blantyre agricultural development division of Malawi.

Kambauwa, Gertrude J. January 2003 (has links)
Agriculture contributes about 70 percent of Malawi's Gross Domestic Product and sustains the livelihood of over 85 percent of the rural population. Soil erosion, which has reached alarming proportions, is threatening this resource base. Despite being rated the most serious environmental problem, soil erosion research lags behind in the listing of agricultural research priorities, particularly with regard to factors influencing the implementation of soil conservation policy and legislation. This study aimed to assess the impact of such policy implementation on smallholder farmer soil conservation practices. A postal, self administered, structured questionnaire was used to interview twenty-three farmers and fourteen agricultural extension staff members. The questions were designed to assess the influence of their perceptions of soil erosion as a problem and its causes. They also sought to assess how effectively relevant policy had been implemented before and after independence. Socio-economic information was additionally elicited from the farmers. After preliminary analysis of these questionnaires, ten days was spent in the field verifying data collected. A Spearman's Rank correlation analysis at 95 percent confidence level was carried out between various components of the farmers' socioeconomic profile data and their responses to the perception questions. Perceptions regarding different aspects of soil erosion and conservation were found to be influenced by the sex, age and educational level of respondents. The study revealed that both farmers and extension staff perceived soil erosion as a problem, had a sound knowledge of the mechanics of the process and attributed it to anthropogenic factors. While both farmers and extension staff attributed declining yields and fertility to accelerated soil erosion, they appeared to have difficulty in identifying physical indicators of such activity in the field. The study also revealed that both believed the top-down approach of the pre-independence period and the post-independence to 1990 period, had been partially effective. Since 1990, policy implementation has become more effective as a result of a more democratic governance and increased extension staff awareness of sustainability concepts which stress the need to incorporate the aspirations of farmers in a bottom-up implementation. This awareness led to the formulation of a new soil and water conservation policy in 1996 which ensures the voices of decision makers are taken into account in policy review. Once legislated, this policy bodes well for further improvements in soil conservation efforts in Malawi. However, the study also revealed that effective implementation of this policy will be dependent on the government providing adequate support and skills to both extension staff and farmers. / Thesis (M.Sc.)-University of Natal, Durban, 2003.
127

Soil loss and run-off in Umfolozi Game Reserve and the implications for game reserve management.

Venter, Johan. January 1988 (has links)
Two management blocks were set aside in Umfolozi Game Reserve (UGR) to compare different management approaches. In one, the non-cull block, a noninterventionist policy was followed and no large mammals were removed, while the other, the cull block was subjected to the same game removal treatment as the remainder of the reserve. The main objectives of this study were to determine the relationships between vegetation, soil surface variables and both soil loss and rainfall run-off, to derive predictive models for run-off and soil loss based on vegetation and soil surface variables, to determine the relationship between different levels of soil erosion and the production potential of soils, and to determine the relationship between different levels of soil erosion and herbaceous species diversity. Rainfall simulator trials and natural run-off plots were used to collect quantitative data on soil loss and run-off. Bivariate scattergrams showed that the relationship between soil surface and vegetation variables plotted against soil loss was curvilinear. "Susceptibility to erosion" showed the highest positive correlation, and "surface cover" the highest negative correlation with soil loss. The relationship between annual run-off and both the soil surface and vegetation variables was also curvilinear, with "soil capping" showing the highest positive and "litter cover" the highest negative correlation with run-off. Using multiple regression analysis it was found that "susceptibility to erosion" and predictors of annual soil loss. "surface cover" were the best "Soil capping" and "percentage contribution of run-off. forbs" were the best predictors of annual No clear relationship between either soil loss and stocking rate, or run-off and stocking rate was apparent in the two experimental blocks, and the differences in soil loss and run-off could not be explained by differences in stocking rate alone. There were however defects in the experimental design which invalidated the assumption that the stocking ~ate diffe~entia1 management blocks would inc~ease with time. between the two Because of the above deficiency, an a1te~native study a~ea on the weste~n bounda~y fence, which allowed fo~ pai~ed sampling sites on eithe~ side of the fence, was chosen. Ge~lach t~oughs we~e used to measu~e soil loss. The g~eatest va~iabi1ity in soil loss was explained by the position of the plots on the slope ~athe~ than whethe~ the plots we~e in UGR o~ in adjacent KwaZu1u. Simi1a~ly, diffe~ences in topog~aphy, ~athe~ than diffe~ences in 1anduse, exe~ted an ove~~iding effect on A-ho~izon depth, he~bage accumulation and g~ass species ~ichness. Conside~ing the ~esu1ts obtained, the opinion that a noninte~ventionist policy would lead to a decline in vegetation p~oductivity and to a 10ng-te~m ~eduction in species dive~sity appea~s to be unfounded. Finally, based on the data collected and on a ~eview of cu~~ent scientific 1ite~atu~e, changes to the Natal Pa~ks Boa~d soils policy and objectives a~e suggested, and the objectives a~e t~ans1ated into ope~ationa1 management goals. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1988.
128

The human relationship to agricultural land

Ives, Malcolm J. Unknown Date (has links) (PDF)
Through agriculture, humans have an intimate relationship to the land. Agriculture provides people with a link to the fertility of the earth in the production of resources for food, clothing and shelter. However, despite the fundamental dependence of humans on the earth’s fertility, people throughout history have transformed and degraded the natural landscapes of their agricultural lands. Continuation of this degradation will threaten the land’s ability to sustain the world’s increasing human populations. / This thesis investigates how agriculturalists might use the land without degrading it. The investigation focuses on the nature of the human-land relationship and begins with an examination of myth as an expression of the human relationship to the cosmos, including to the gods and the earth. Jungian psychology is examined for its explanation of symbolic perception and psychological attitude. Theological views on the human relationship to God are examined. These examinations of myth, psychology and theology identify two fundamental motifs in human thought about relationship to the cosmos: the Eros motif which derives from an egocentric attitude, and is associated with domination of nature; and the Agape motif which derives from the physically reintegrated attitude, and is associated with creativity through the development of fertility. The examination of background theory is followed by motif-analysis of theories of the human-land relationship, and of two case studies - the historical development of agriculture in Australia, and a comparative study of soil conservation and keyline farming. The analyses indicate that most theory and practice of agriculture is conducted with the Eros motif which leads to land degradation and responsive attempts at remedial actions. In contrast, keyline farming is indicative of the Agape motif in its development of the natural fertility of the land. / The thesis concludes that the humanised landscapes of the world follow symbolic patterns generated by psychological attitudes. The egocentric attitude leads to human domination of the land and its degradation through the transformation and simplification of the land’s ecological structure, and the superimposition of centralised settlement patterns which are often incompatible with the natural systems. Alternatively, people with the reintegrated attitude would nurture the land’s natural fertility through the integration of land utilisation and settlement patterns with the landscapes’ natural configurations and processes. Western thought is dominated by the Eros motif, inherited through religious mythology and perpetuated through Western education based on rationalism, reductionism and induction. This ethos tends to divorce humans from psychical and physical nature, and leads to a fragmentary and distorted view of the world. Education is necessary to bring the Agape motif into the consciousness of people and societies. People might then recognise and experience their direct relationship to the world and to have a creative relationship to the land.
129

Improved soil and water conservatory managements for cotton-maize rotation system in the western cotton area of Burkina Faso /

Ouattara, Korodjouma, January 2007 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2007. / Härtill 3 uppsatser.
130

Erosion modelling under different land use management practices

Pudasaini, Madhu Sudan. January 2003 (has links)
Thesis (M.Eng. (Hons.)) -- University of Western Sydney, 2003. / "Thesis submitted for the degree of Masters of Engineering (Honours) Environmental Engineering" Includes bibliography.

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