Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002. / Thesis documentation sheet inserted. Appendix reprints five published papers and manuscripts, three co-authored with others. Includes bibliographical references. Also available electronically via World Wide Web in PDF format; online version lacks appendix.

Landscape management is often referred to as a holistic concept, which deals with large-scale processes and multidisciplinary manners in regards to natural resource use with ecological and livelihood considerations. Seen in this light, landscape transformation should be understood within the context of the human-nature relationship, viewing human activities and their institutions as an essential part of the system rather than as external agents. When it comes to the landscape planning and management related to cotton farming in Gujarat, there has been diversity of interest groups such as local communities, governments, corporations and non-governmental organisations. In the present study, I examine two case studies of cotton production pertaining to the Gujarat region in order to study the opportunities and challenges faced by local farmers in the process of developing agriculture. In the first case study on Cotton Improvement Program in the nineteenth century, I highlight the socioecological consequences of the colonial cotton project and how it relates to the social dynamics of networks and agricultural landscape management. The second case study examines current debates regarding the social, economic and environmental impacts of genetically modified (GM) cotton on India’s social and natural landscape. This thesis emphasises that there are recursive motifs between the two case studies in terms of the local resistances, power relations and possible environmental effects, which can be explained through the state of ‘global core’ and ‘periphery’, and partly the framework of ecologically unequal exchange. The analysis of recurring patterns concludes that exploring the narratives of local experiences offers a number of significant details that show complex power dynamics manifested through constant struggles and resistances by ‘peripheral agent’.

Local food networks are often defined as presenting a variety of alternative food production, consumption, and distribution practices to the conventional food system such as community-supported-agriculture, farmers markets, and community gardens. Local food initiatives are commonly proposed as a model for the future of sustainable agriculture, and in the region of Portland, Oregon the abundance of such alternative venues results from the area's natural surroundings and smart planning. The region is host to 39 farmers markets and Portland is often hailed as one of the country's most sustainable cities. This study examines the role of local food networks in preserving agricultural land uses and livelihoods in Washington County, Oregon, a rapidly growing county adjacent to the city of Portland. I focus on small-scale agricultural landscapes where the producer sells at farmers markets or through community supported agriculture (CSAs). I explore farmers' concerns about urbanization and farmland preservation, their relationship to urban markets, motives to become a farmer, engagement with the surrounding environment, and their difficulties participating in local food networks. In addition, I explore farmers market managers' insights into the development of local food networks and how they see their markets supporting small-scale farmers. In a survey of consumers I examine consumer motives to `buy local' and consumer concerns about farmland preservation. The research is qualitative and explores: 1) the processes shaping the development of local food networks; 2) how particular ideas and images of nature and the countryside inform both consumer desires to purchase from farmers selling locally and; 3) how those same images of nature and the countryside inform and motivate people to become farmers participating in local food networks. In so doing, I argue that the networks that sustain urban and rural systems are important in understanding the development of local food networks, and that the preservation of economically and culturally important agricultural lands in Washington County depends on a diversity of opinions and rural narratives in order to preserve small-scale sustainable farmlands close-in to cities. The conclusion is that local food sold through alternative venues can be used as a means to preserve and develop specific and manageable farm sites and agricultural land uses but the impact is limited. Large scale impacts on agricultural land uses and livelihoods will depend on planners and advocates agreeing on policies that encompass a diversity of opinions, land uses, and land managers, while understanding the array of networks beyond the city that sustain both urban and rural systems.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / The transfer of nutrients from US Midwest croplands into surface waters causes eutrophication and a decline in water quality. Temporary retention of nutrient-rich runoff in constructed wetlands can help mitigate these negative impacts through physical entrapment and biological transformation of nitrogen (N) and phosphorus (P). However, with the expectation that wet-dry periods will be more frequent in the region, there is a need to better understand the mechanisms that control nutrient retention and release in US Midwest wetlands constructed on former croplands. In this study, soil cores (30 cm long, 20 cm diam) were collected from two constructed wetlands (4 and 8-yr old), and the surface (0-20 cm) and subsurface (40-60 cm) layers of a cropland where a constructed wetland will be constructed in the future. Soil cores were subjected to either a moist or a dry treatment for 5 weeks, and then flooded with stream water (water depth 6 cm). The flux of nutrients, N2O, cations, and variation in floodwater chemistry (pH and ORP) were monitored for another 5 week period. Porewater was tested during the final 3 weeks of the experiment. Nitrate (0.1-130 mg N m-2 d-1) and inorganic P (Pi) fluxes (0.09-2.9 mg P m-2 d-1) were significantly higher in the dry treatment cores. Regardless of site, the dry treatment also resulted in higher floodwater NO3- concentrations suggesting organic matter mineralization and mineral N build up during the drying phase. However, this initial NO3- release was rapidly denitrified as indicated by the sharp increase in N2O production during that period. In contrast to N, the release of Pi was significantly higher in cores from the cropland. Soil at these sites had higher water extractable Pi and total P. Contrary to the study hypothesis and the results of previous studies, Pi concentration in floodwater and porewater was not correlated with dissolved Fe suggesting that reductive dissolution was not the dominant process controlling P release in US Midwest mineral soils developed from calcareous glacial till. Rather, variation in Ca2+ concentration and its relationship with Pi suggest that dissolution of Ca-containing minerals may be more important and should be the focus of future studies examining the geochemistry of P in these constructed wetlands.

Landscape heterogeneity is thought to differ among farm management types (i.e. organic and conventional), and this difference is hypothesized to result in variations in pest control by natural enemies. However, it is unclear if these variations in pest control are driven by landscape structure or by farm management practices themselves. Remotely sensed datasets were used to describe the landscape structure surrounding a group of organic and conventional caneberry farms in Oregon and Washington that have different leafroller parasitism rates attributed to farm management type. A finer scale survey was done at one of the farms using the remotely sensed data as well as field surveys. Landscape metrics of diversity, richness and percent non-crop were used to describe the landscapes surrounding the farm fields at scales ranging from 0.05 km to 5.00 km for the large scale study, and 0.05 km to 0.20 km for the fine scale study. In the fine scale study, data on parasitoid species assemblages, diversity, and parasitism rate were collected and analyzed against the calculated landscape metrics spatially and seasonally. The purpose of this study was to quantify effects of farm management type on habitat structure, effect of habitat structure on leafroller parasitism rate, and to access correlations between landscape metrics calculated at the landscape and field scale. Overall, the farms were embedded in a landscape that was broadly similar, with very few differences in landscape structure occurring between organic and conventional farms. Organic farms had higher vegetation height class diversity at the largest scale compared to conventional farms, while conventional farms had significantly higher percent non-crop area compared to organic farms. There was no significant effect of any of the calculated landscape metrics on parasitism rates. In the field scale study, no correlations were found between habitat metrics and parasitism rates, or between field based metrics and those calculated at the landscape scale. The results of this study suggest that conventional and organic caneberry farms in the Willamette Valley are broadly similar in the habitat conditions they provide parasitoids. This suggests that management changes to pesticide use alone could increase levels of leafroller biological control on conventional farms to levels that are comparable to those seen on organic farms. Our comparisons of the landscape scale and field scale landscape metrics showed no connection, this suggests that direct comparisons cannot be made with these particular metrics at these very different scales. Rather than comparing these types of data, it may be more useful to combine them in order to increase the resolution and predictive power of remotely sensed data for describing landscapes at broad scales. / Graduation date: 2013

Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2005. / In the past, development was allowed in agricultural areas which would not be acceptable under current planning policy. There is a growing need to develop and maintain highly productive and ecologically stable agricultural systems. One approach to encourage better land management and utilisation is the international certification of a farm’s production practices.