967 resultados para Land systems


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This project examined the potential for historical mapping of land resources to be upgraded to meet current requirements for natural resource management. The methods of spatial disaggregation used to improve the scale of mapping were novel and provide a method to rapidly improve existing information. The thesis investigated the potential to use digital soil mapping techniques and the multi-scale identification of areas within historical land systems mapping to provide enhanced information to support modern natural resource management needs. This was undertaken in the Burnett Catchment of South-East Queensland.

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Thesis (Ph.D.)--University of California, Berkeley, 1920.

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"USDA Forest Service research paper."

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The Great Barrier Reef (GBR) is the largest reef system in the world; it covers an area of approximately 2,225,000 km² in the northern Queensland continental shelf. There are approximately 750 reefs that exist within 40 km of the Queensland coast. Recent research has identified that poor water quality is having negative impacts on the GBR (Haynes et al. 2007). The Fitzroy Basin covers 143,000 km² and is the largest catchment draining into the GBR as well as being one of the largest catchments in Australia (Karfs et al. 2009). The Burdekin Catchment is the second largest catchment entering into the GBR and covers 133,432 km².The prime determinant for the changes in water quality entering into the GBR have been attributed to grazing, with beef production the largest single land use industry comprising 90% of the land area (Karfs et al. 2009). Extensive beef production contributes over $1 billion dollars to the national economy annually and employs over 9000 people, many in rural communities (Gordon 2007). ‘Economic modelling of grazing systems in the Fitzroy and Burdekin catchments’ was a joint project with the Fitzroy Basin Association and the Queensland Department of Employment Economic Development and Innovation. The project was formed under the federally funded Caring For Our Country and the Reef Rescue programs. The project objectives were as follows; * Quantifying the costs of over-utilising available pasture and the resulting sediment leaving a representative farm for four of the major land systems in the Burdekin or Fitzroy catchments and identifying economically optimal pasture utilisation rates * Estimating the cost of reducing pasture utilisation rates below the determined optimal * Using this information, guide the selection of appropriate tools to achieve reduced utilisation rates e.g. extension process versus incentive payments or a combination of both * Model the biophysical and economic impacts of altering grazing systems to restore land condition e.g. from C condition to B condition for four land systems in the Burdekin or Fitzroy catchments.

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Animal production, hay production and feeding, winter forage composition changes, and summer pasture yields and nutrient composition of a year-round grazing system for spring-calving and fall-calving cows were compared to those of a conventional, minimal land system. Cows in the year-round and minimal land systems grazed forage from smooth bromegrassorchardgrass-birdsfoot trefoil (SB-O-T) pastures at 1.67 and 3.33 acres, respectively, per cow in the summer. During the summer, SB-O-T pastures in the year-round grazing system also were grazed by stockers at 1.67 stockers per acre, and spring-calving and fall-calving cows grazed smooth bromegrass–red clover (SB-RC) and endophyte-free tall fescue–red clover (TF-RC) at 2.5 acres per cow for approximately 45 days in midsummer. In the year-round grazing system, spring-calving cows grazed corn crop residues at 2.5 acres per cow and stockpiled SB-RC pastures at 2.5 acres per cow; fallcalving cows grazed stockpiled TF-RC pastures at 2.5 acres per cow during winter. In the minimal land system, in winter, cows were maintained in a drylot on first-cutting hay harvested from 62.5–75% of the pasture acres during summer. Hay was fed to maintain a body condition score of 5 on a 9-point scale for springcalving cows in both systems and a body condition score of 3 for fall-calving cows in the year-round system. Over 3 years, mean body weights of fall-calving cows in the year-round system did not differ from the body weights of spring-calving cows in either system, but fall-calving cows had higher (P < .05) body condition scores compared to spring-calving cows in either system. There were no differences among all groups of cows in body condition score changes over the winter grazing season (P > .05). During the summer grazing season, fall-calving cows in the year- round system and springcalving cows in the minimal land system gained more body condition and more weight (P < .05) than springcalving cows in the year-round grazing system. Fall calves in the year-round system had higher birth weights, lower weaning weights, and lower average preweaning daily gains compared to either group of spring calves (P < .05). However, there were no significant differences for birth weights, weaning weights, or average pre-weaning daily gains between spring calves in either system over the 3-year experiment (P > .05). The amount of total growing animal production (calves and stockers) per acre for each system did not differ in any year (P > .05). Over the 3-year experiment, 1.9 ton more hay was fed per cow and 1 ton more hay was fed per cow–calf pair in the minimal land system compared to the year-round grazing system (P < .05).

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Land systems are increasingly influenced by distal connections: the externalities and unintended consequences of social and ecological processes which occur in distant locations, and the feedback mechanisms that lead to new institutional developments and governance arrangements. Economic globalization and urbanization accentuate these novel telecoupling relationships. The prevalence of telecoupling in land systems demands new approaches to research and analysis in land science. This chapter presents a working definition of a telecoupled system, emphasizing the role of governance and institutional change in telecoupled interactions. The social, institutional, and ecological processes and conditions through which telecoupling emerges are described. The analysis of these relationships in land science demands both integrative and diverse epistemological perspectives and methods. Such analyses require a focus on how the motivations and values of social actors relate to telecoupling processes, as well as on the mechanisms that produce unanticipated outcomes and feedback relationships among distal land systems.

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In land systems, equitably managing trade-offs between planetary boundaries and human development needs represents a grand challenge in sustainability oriented initiatives. Informing such initiatives requires knowledge about the nexus between land use, poverty, and environment. This paper presents results from Lao PDR, where we combined nationwide spatial data on land use types and the environmental state of landscapes with village-level poverty indicators. Our analysis reveals two general but contrasting trends. First, landscapes with paddy or permanent agriculture allow a greater number of people to live in less poverty but come at the price of a decrease in natural vegetation cover. Second, people practising extensive swidden agriculture and living in intact environments are often better off than people in degraded paddy or permanent agriculture. As poverty rates within different landscape types vary more than between landscape types, we cannot stipulate a land use–poverty–environment nexus. However, the distinct spatial patterns or configurations of these rates point to other important factors at play. Drawing on ethnicity as a proximate factor for endogenous development potentials and accessibility as a proximate factor for external influences, we further explore these linkages. Ethnicity is strongly related to poverty in all land use types almost independently of accessibility, implying that social distance outweighs geographic or physical distance. In turn, accessibility, almost a precondition for poverty alleviation, is mainly beneficial to ethnic majority groups and people living in paddy or permanent agriculture. These groups are able to translate improved accessibility into poverty alleviation. Our results show that the concurrence of external influences with local—highly contextual—development potentials is key to shaping outcomes of the land use–poverty–environment nexus. By addressing such leverage points, these findings help guide more effective development interventions. At the same time, they point to the need in land change science to better integrate the understanding of place-based land indicators with process-based drivers of land use change.

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Land systems are the result of human interactions with the natural environment. Understanding the drivers, state, trends and impacts of different land systems on social and natural processes helps to reveal how changes in the land system affect the functioning of the socio-ecological system as a whole and the tradeoff these changes may represent. The Global Land Project has led advances by synthesizing land systems research across different scales and providing concepts to further understand the feedbacks between social-and environmental systems, between urban and rural environments and between distant world regions. Land system science has moved from a focus on observation of change and understanding the drivers of these changes to a focus on using this understanding to design sustainable transformations through stakeholder engagement and through the concept of land governance. As land use can be seen as the largest geo-engineering project in which mankind has engaged, land system science can act as a platform for integration of insights from different disciplines and for translation of knowledge into action.

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This paper describes the employment of two experienced graziers as consultants to apply and evaluate a model for calculating 'safe' long-term grazing capacities of individual properties. The model was based on ecological principles and entailed estimates of average annual forage grown (kglha) on the different land systems on each property and the calculation of the number of livestock (dry sheep equivalents, DSE) required to 'safely' utilise this forage. The grazier consultants applied and evaluated the 'safe' grazing capacity model on 20 properties of their choosing. For evaluation, model results were compared with; (a) the Department of Lands rated carrying capacities for those properties and (b) the grazing capacity assessed independently by the owners of those properties. For the 20 properties, the average 'safe' grazing capacity calculated by the model (21.0 DSE/kmZ) was 8% lighter than the average of the owner assessed capacities (22.7 DSE/kmZ), which in tum was 37% lighter than the average of the pre-1989 Department of Lands rated carrying capacity (31.0 DSE/kmZ). The grazing land management and administrative implications of these results and the role graziers played as consultants are discussed.

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This work presents a comparison of alkaline and cristaline terrains of an area inside a Poços de Caldas (MG) contry for appropriate urban expansion. The study area has 52km2 through rural and urban terrains with geological and geomorphological differences. At present Poços de Caldas has more than 130 thousand people and expansion government plans are from 1993 showing the necessity of studies of infrastructure to population and tourists. At last 40 years the city became a place with job offers in bauxite minning causing a population increase about 200%. At this way this work uses the Vedolvello (2000)´s method of terrains physiographic compartimentalization (UBCs) with integrated analysis (Land Systems) made by remote sensing products (air photos). After that field trips was performed to check unity limits by observation of rocks, relief and weathering soil profile. The main results are Engineering Geological Map and a classification table of Basic Units of Compartimentalization to presents the characteristics to uses and soil occupation.

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Este trabalho teve como tema principal o mapeamento geológico-geotécnico de determinado trecho da Bacia do rio Passa Cinco, e sua suscetibilidade a processos erosivos lineares, fluviais e de assoreamento. A área tem 129km2 e está situada principalmente no município de Ipeúna, estado de SP. O estudo foi desenvolvido a partir de análise por sensoriamento remoto (land systems) de fotos aéreas e associação a mapas geológicos, geomorflógicos, pedológicos e perfis de alteração. Esta análise integrada permitiu a divisão da área em dez Unidades Básicas de Compartimentação (UBCs), com base na metodologia apresentada por VEDOVELLO em diversos trabalhos. Foram obtidas dez Unidades Básicas de Compartimentação, apresentadas na ordem de ocorrência na Depressão Periférica (6 Unidades) e no relevo escarpado (4 Unidades). A partir desta compartimentação, verificações em campo e imagens de satélite foram adotados parâmetros para a análise quanto a suscetibilidade a aos processos erosivos lineares, fluviais e de assoreamento, obtendo-se três Unidades com alta suscetibilidades a processos erosivos lineares, e uma Unidade com alta suscetibilidade a processos erosivos fluviais e assoreamento. Como produto foi gerado um Mapa geológico–geotécnico em escala 1:50.000, com perfil representativo da área e uma tabela-síntese com as principais características e análise de suscetibilidade aos processos analisados

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The replacement of native vegetation by other land uses is one of the main degrading ecosystem agents, being the most important component of terrestrial environments, natural or with different levels of human disturbance, besides being the main substrate used by plants to obtain conditions soil for its development. In this context, there is the need to adopt the use and sustainable management of land systems. The study aimed to evaluate what is forest restoration system more efficient degraded areas, based on the potential recovery of physical, chemical, carbon and biological activity in the soil. The work was conducted in a forest restoration area UTFPR- Campus two neighbors, whose experiment was established in October 2010. The experimental design is completely randomized, with four replications and experimental plot of 40 m wide by 54 m long ( 2160 m2) were collected and six sampling points per plot. The soil is classified as a Typic. The models evaluated are: 1 - natural or passive regeneration; 2 - Nucleation; 3 - Planting trees in the total area under lines fill and diversity (total planting); 4 - Reference area (forest). The collection of soil samples in layers of 0.0-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m was carried out in October 2013 and evaluated physical attributes of texture, bulk density, total porosity, microporosity and soil macroporosity and stability of water in households, chemical properties, and total organic carbon (TOC) and physical particle size fractionation and soil biological activity. To find the best forest restoration model, we designed a Restoration Quality Weighted Index for each variable analyzed. Natural regeneration and total plantation showed generally better soil aggregation over 0.10 m and nucleation volume of similar porosity the forest for these layers. There were no differences between the models below 0.10 m for the variables aggregation and soil porosity. The nucleation template had the lowest bulk density, but being greater than the density in the layer forest 0.05-0.10 m, however, was similar to below 0.10 m above the ground. The models had chemical properties similar to or greater than the forest. The forest had the highest stock of COT and carbon associated with minerals (CAM), but natural regeneration was similar to the particulate organic carbon (POC) in the superficial layers of the soil (0-0.10 m), below 0, 10 m, the forest showed higher stock of COT and COP on the ground. The highest peak of C-CO2 emissions occurred in the 28-35 day range where the total plantation was similar to forest. After four years of experiments, it was found that the effect of restoration methods on physical attributes and soil carbon restricted to 0.10 m deep.

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There is no doubt that fraud in relation to land transactions is a problem that resonates amongst land academics, practitioners, and stakeholders involved in conveyancing. As each land registration and conveyancing process increasingly moves towards a fully electronic environment, we need to make sure that we understand and guard against the frauds that can occur. What this paper does is examine the types of fraud that have occurred in paper-based conveyancing systems in Australia and considers how they might be undertaken in the National Electronic Conveyancing System (NECS) that is currently under development. Whilst no system can ever be infallible, it is suggested that by correctly imposing the responsibility for identity verification on the appropriate individual, the conveyancing system adopted can achieve the optimum level of fairness in terms of allocation of responsibility and loss. As we sit on the cusp of a new era of electronic conveyancing, the framework suggested here provides a model for minimising the risks of forged mortgages and appropriately allocating the loss. Importantly it also recognises that the electronic environment will see new opportunities for those with criminal intent to undermine the integrity of land transactions. An appreciation of this now, can see the appropriate measures put in place to minimise the risk.

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Land use and agricultural practices can result in important contributions to the global source strength of atmospheric nitrous oxide (N2O) and methane (CH4). However, knowledge of gas flux from irrigated agriculture is very limited. From April 2005 to October 2006, a study was conducted in the Aral Sea Basin, Uzbekistan, to quantify and compare emissions of N2O and CH4 in various annual and perennial land-use systems: irrigated cotton, winter wheat and rice crops, a poplar plantation and a natural Tugai (floodplain) forest. In the annual systems, average N2O emissions ranged from 10 to 150 μg N2O-N m−2 h−1 with highest N2O emissions in the cotton fields, covering a similar range of previous studies from irrigated cropping systems. Emission factors (uncorrected for background emission), used to determine the fertilizer-induced N2O emission as a percentage of N fertilizer applied, ranged from 0.2% to 2.6%. Seasonal variations in N2O emissions were principally controlled by fertilization and irrigation management. Pulses of N2O emissions occurred after concomitant N-fertilizer application and irrigation. The unfertilized poplar plantation showed high N2O emissions over the entire study period (30 μg N2O-N m−2 h−1), whereas only negligible fluxes of N2O (<2 μg N2O-N m−2 h−1) occurred in the Tugai. Significant CH4 fluxes only were determined from the flooded rice field: Fluxes were low with mean flux rates of 32 mg CH4 m−2 day−1 and a low seasonal total of 35.2 kg CH4 ha−1. The global warming potential (GWP) of the N2O and CH4 fluxes was highest under rice and cotton, with seasonal changes between 500 and 3000 kg CO2 eq. ha−1. The biennial cotton–wheat–rice crop rotation commonly practiced in the region would average a GWP of 2500 kg CO2 eq. ha−1 yr−1. The analyses point out opportunities for reducing the GWP of these irrigated agricultural systems by (i) optimization of fertilization and irrigation practices and (ii) conversion of annual cropping systems into perennial forest plantations, especially on less profitable, marginal lands.