No description available.

<p> Adoption of nitrogen (N) management strategies to minimize gaseous N loss from agriculture while maintaining high yield production is increasingly important for an exponentially growing population. Agricultural management on poorly-drained claypan soils in the Midwestern U.S. make corn (<i> Zea mays</i> L.) production even more challenging due to the subsoil&rsquo;s low permeability, which may result in wetter soil conditions and relatively larger amounts of soil N₂O emissions during the growing season. The objective of this study was to determine the effects of urea fertilizer placement with and without the addition of a nitrification inhibitor (NI) on corn yield, N use efficiency (NUE), and cumulative soil N2O emissions on a Northeastern Missouri claypan soil. The fertilizer strategies utilized in this study consisted of deep-banded urea (DB) or urea plus nitrapyrin [2-chloro-6-(trichloromethyl) pyridine] (DB+NI) at a depth of 20 cm compared to urea broadcast surface applied (SA) or incorporated to a depth of 8 cm (IA). The addition of a NI with deep-banded urea resulted in 27% greater apparent N recovery efficiency than all other N treatments. Additionally, DB+NI had 54 and 55% lower cumulative soil N₂O emissions than IA and SA treatments in the two combined growing seasons. These results suggest that deep placement of urea with or without nitrapyrin is an effective management strategy for increasing corn yield and reducing N loss on a claypan soil.</p><p>

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Landscape connectivity is a concept that refers to a landscape's structural and functional continuity, allowing for the flow of water, nutrients, energy, organisms, genes, and disturbances at many spatial and temporal scales. The loss of landscape connectivity leads to ecosystem fragmentation, which in turn contributes to a decline in biodiversity and threatens many species around the world. The importance of maintaining landscape connectivity is becoming recognized as a fundamental principle in land use planning. The purpose of this dissertation is to examine how the theory of landscape connectivity has been applied in Ontario's land use planning policy and practice between 1970 and 2008. This includes evaluating the degree to which theory has been applied to practice in landscape connectivity planning. In addition, the work investigates the processes that facilitated the movement from theory to practice in planning for landscape connectivity. Broadly framed within the theories of conservation biology, the research approach is qualitative and the research design includes a literature review, content analysis, and case study research. This research found that there has been an evolution of theory to practice in planning for landscape connectivity in Ontario between 1970 and 2008. The introduction of conservation biology principles created a growing public awareness, which contributed to rising pressure on the Government of Ontario to reform its land use planning policies. The theory of landscape connectivity is included in key land use planning legislation and policies and is now an accepted part of planning for natural heritage in the province. The Ontario Municipal Board has regard for landscape connectivity as a legitimate planning concern. In the majority of cases in the last decade in which landscape connectivity was identified as a deciding factor, the Ontario Municipal Board ruled in favour of protecting landscape connectivity. Planners in Ontario are expected to plan for landscape connectivity, but Ontario’s planning law and policy does not provide strong direction to planners on the issue of landscape connectivity. Recommendations for the Government of Ontario, based on the research findings, include planning for landscape connectivity at a provincial scale, creating a guidance document specifically for landscape connectivity and revising the Provincial Policy Statement.

Landscape connectivity is a concept that refers to a landscape's structural and functional continuity, allowing for the flow of water, nutrients, energy, organisms, genes, and disturbances at many spatial and temporal scales. The loss of landscape connectivity leads to ecosystem fragmentation, which in turn contributes to a decline in biodiversity and threatens many species around the world. The importance of maintaining landscape connectivity is becoming recognized as a fundamental principle in land use planning. The purpose of this dissertation is to examine how the theory of landscape connectivity has been applied in Ontario's land use planning policy and practice between 1970 and 2008. This includes evaluating the degree to which theory has been applied to practice in landscape connectivity planning. In addition, the work investigates the processes that facilitated the movement from theory to practice in planning for landscape connectivity. Broadly framed within the theories of conservation biology, the research approach is qualitative and the research design includes a literature review, content analysis, and case study research. This research found that there has been an evolution of theory to practice in planning for landscape connectivity in Ontario between 1970 and 2008. The introduction of conservation biology principles created a growing public awareness, which contributed to rising pressure on the Government of Ontario to reform its land use planning policies. The theory of landscape connectivity is included in key land use planning legislation and policies and is now an accepted part of planning for natural heritage in the province. The Ontario Municipal Board has regard for landscape connectivity as a legitimate planning concern. In the majority of cases in the last decade in which landscape connectivity was identified as a deciding factor, the Ontario Municipal Board ruled in favour of protecting landscape connectivity. Planners in Ontario are expected to plan for landscape connectivity, but Ontario’s planning law and policy does not provide strong direction to planners on the issue of landscape connectivity. Recommendations for the Government of Ontario, based on the research findings, include planning for landscape connectivity at a provincial scale, creating a guidance document specifically for landscape connectivity and revising the Provincial Policy Statement.

<p> As developing countries experience substantial urban growth and expansion, remotely sensed based estimates of population and demographic characteristics can provide researchers and humanitarian aid workers timely and spatially explicit information for planning and development. In this exploratory analysis, high spatial resolution satellite imagery, in combination with fine resolution census data, is used to determine the degree to which spatial features are able to identify spatial patterns of demographic variables in Accra, Ghana. Traditionally when using satellite imagery, spectral characteristics are used on a per-pixel basis to produce land cover classifications; however, in this study, a new methodology is presented that quantifies spatial characteristics of built-up areas, and directly relates them to census-derived variables. Spatial features are image metrics that analyze groups of pixels in order to describe the geometry, orientation, and patterns of objects in an image. By using spatial features, city infrastructure variations, such as roads and buildings, can be quantified and related to census-derived variables, such as living standards, housing conditions, employment and education. To test the associations between spatial patterns and demographic variables, five spatial features (line support regions, PanTex, histograms of oriented gradients, local binary patterns, and Fourier transform) were quantified and extracted from the imagery, and then correlated to census-derived variables. Findings demonstrate that, while spectral information (such as the normalized difference vegetation index) reveals many strong correlations with population density, housing density, and living standards, spatial features provide comparable correlation coefficients with density and housing characteristics. The results from this study suggest that there are relationships between spatial features derived from satellite imagery and socioeconomic characteristics of the people of Accra, Ghana.</p>

Hierarchical crop growth models can contribute signi®cantly to land quality research because the yield gap between the estimated optimum and the actual crop production has been identi®ed as a major land quality indicator. This study describes a three-level, hierarchical crop production model, simulating radiation-thermal, water-limited and natural production potentials of annual crops. Input requirements have been kept low to ensure its applicability to developing regions, which often have access only to limited data. The simplicity of this model also has disadvantages: inconsistencies have been reported when applying this model in semiarid regions, which are characterized by very irregular rainfall patterns. Revision of the water balance, which simulates the availability of water, was required. The modi®ed model was validated using the experimental yields of maize and sun¯ower in Guquka, a semiarid region of South Africa. Yields were estimated very well, possible improvements to crop production were identi®ed and implications for land-use planning highlighted. Yield gap analysis revealed that radiation, sunshine and temperature are favourable for crop production, but the heavy dependence on rainfall makes the region very vulnerable to drought, with devastating impact on yields. The generally low chemical soil fertility further reduces crop performance.

No description available.

<p> I theorize and offer some evidence that humans inadvertently risk exacerbating the loss of maintenance-dependent species on private land by using species-based land-use regulation to seek other benefits. Drawing evidence primarily from the US, I argue that such regulation poses a risk to maintenance-dependent species, that humans routinely disregard this risk, and that this disregard widely serves to defend the power of individuals and organizations to use such regulation to seek other benefits. I suggest this implies that with constraints on public funding, humans might improve the survival of some species by clarifying the purpose of such regulation and considering openly refraining from such regulation for some species. I also suggest such change might depend on articulating the issue as whether the survival of a species could ever depend on individuals having a right to conserve or maintain it without selectively incurring harm from regulation intended to save it.</p>

<p> The impact of beach access paths on dune vegetation was investigated on the Isle of Palms, SC. Understanding the impacts of the most direct form of disturbance in this system (beach access paths) is of increasing importance from ecological and economic perspectives. Vegetation characteristics were measured along transects in foredune, mid dune and back dune communities at set distances from beach access paths. Survey was conducted to allow comparisons between path types and materials. Results indicate that beach access paths have a significant impact on beach dune vegetation. Sand paths cause greater reductions in vegetative cover than wooden paths and wooden paths raised at least 0.7m from the sand surface cause the least reduction in vegetation cover. Closely spaced paths reduce the species richness and percent of vegetative cover more than paths spaced at least 40 m apart. Current regulations can be minimally altered to improve dune vegetation and dune stability. Regulations requiring construction of raised wooden paths and disallowing private sand paths would greatly improve dune vegetation continuity. Additionally, voluntary path sharing of neighboring properties could significantly reduce the number of paths per mile of coastline while creating minimal inconvenience for beachfront homeowners and visitors.</p>