148 resultados para Gully


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在分析黄土高原地区的沟沿线、沟沿线上下沟间地和沟谷地土壤侵蚀特征、小流域泥沙来源、坡沟侵蚀产沙关系的基础上,结合廊道的生态功能和以往的研究结果,认为在沟沿线的上部建立草灌与整地工程措施相结合的植物廊道,来拦蓄阻截沟间地的来水来沙,可使流域的土壤侵蚀量减少54.5%~77.0%。

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以浅沟集水区为研究对象,分析了子午岭地区林地被开垦破坏15年后裸露地在不同侵蚀强度和侵蚀方式下的土壤养分流失和土壤微生物数量的变化。结果表明,林地开垦破坏后,土壤侵蚀加剧发展,侵蚀强度达159.7t/(hm2.a),是林地土壤侵蚀量的上千倍。开垦破坏15年后,裸露地浅沟集水区不同地形部位表层土壤全氮、有机碳、速效磷和土壤微生物总数显著减少,同林地相比,依次分别减少37.9%~82.6%、42.7%~86.4%、24.2%~80.3%和31.8%9~2.0%。在裸露地浅沟集水区梁坡随坡长的增加,表层土壤有机碳、全氮和速效磷含量及微生物总数呈显著的下降趋势,且沟槽的土壤各养分含量及微生物总数明显低于沟间。裸露地浅沟集水区土壤养分流失强度及微生物数量减少幅度在浅沟集水区的空间分布与土壤侵蚀方式和侵蚀强度相对应。林地开垦破坏15年后,土壤养分以有机碳流失最严重,其次分别为速效磷、全氮;微生物中的真菌减少幅度最大,细菌次之,放线菌减少幅度最小。

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依据在陕西安塞进行的田间试验,研究了黄土丘陵旱农区传统翻耕和免耕及化肥和有机肥对玉米光合速率和气孔导度的影响。结果表明,免耕措施下玉米的光合速率、气孔导度、水分利用效率均高于传统翻耕,气孔导度的日变化与光合速率显著相关。在黄土丘陵区实施免耕既有利于作物对有限降水的高效利用,提高作物产量,也可促进农田系统生产力可持续提高。

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Using satellite images taken on different dates, GIS analysis of aerial photos, bathymetric maps and other field survey data, tidal troughs and major sand ridges in the northern Jiangsu coastal area were contrasted. The results show that there have been three types of movement or migration of tidal trough in this area: (1) Periodic and restricted, this type of trough usually developed along the beaches with immobile gully head as a result of the artificial dams and the swing range increased from gully head to the low reaches, so they have been obviously impacted by human activity and have longer swing periods; (2) Periodic and actively, this kind of trough, which swung with a fast rate and moved periodically on sand ridges, were mainly controlled by the swings of the host tidal troughs and hydrodynamic forces upon tidal sand ridge and influenced slightly by human constructions; (3) Steadily and slowly, they are the main tidal troughs with large scale and a steady orientation in this area and have slow lateral movement. The differences in migration mode of tidal trough shift result in different rates of migration and impact upon tidal sand ridges. Lateral accumulation on current tidal trough and deposition on abandoned tidal troughs are the two types of sedimentation of the tidal sand ridges formation. The whole radial sand ridge was generally prone to division and retreat although sand ridges fluctuated by the analysis of changes in talwegs of tidal troughs and shorelines of sand ridges.

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The thesis show you seven interpretation models of erosion of MAs1+2 in the west of prospect and eroded gully of middle and east, form the interpretation technique how to built up eroded gully of the Ordovician top, according of the practical demand of oil-gas exploration in the ShanGanNing basin, using seismic information, combining well logging and well drilling data, Carefully analyzing geologic deposition background and well logging data, through a great quantity forward and inversion for geologic model and combination geologic model with seismic section. Related to research of reservoir absorption in the ShanGanNing basin, it firstly introduces PRONY transformation multidimensional filter. It can simultaneously express relationship of frequency and absorption decay coefficient, better than FUSAIPU analysis method; PRONY filter have obtain the better effect in the gas field of ZhenChuanBao in the ShanBei area after adopting PRONY filtering method to predict reservoir absorption, by analyzing fixed well and prediction of non-well drilling. In the ShanGanNing basin, general seismic inversion method can produce evident different results or misunderstanding because wave impedance and lithology, physical property, gas property are not sole, especially while have little impedance contrast and even have contract direction; the author carefully analyzes multi-parameter inversion technique, add natural gamma ray and natural potential and other parameter combined making model inversion method according of theory of seismic inversion and applying reservoir velocity and wave impedance information at last, we get the more directly reservoir physical property parameter, judging reservoir physical property is more exact. In accordance with geologic, seismic feature of Shan basin, the thesis conclude Ordovician system top erosion interpretation technology with ChangQing character, and reservoir thickness prediction technique combining inversion technique with wave character analysis, Reservoir physical property that is mainly absorption factor analysis and multi-parameter inversion and oil-gas prediction technology. These technologies obtain the better result in the oil-gas field exploration and have formed comprehensive research method and technology series with ShanGanNing character.

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Heavy metals, primarily zinc, copper, lead, and chromium, and Polycyclic Aromatic Hydrocarbons (PAHs) are the main hazardous constituents of road runoff. The main sources of these contaminants are vehicle emission, mostly through wear and leakage, although erosion of the road surface and de-icing salts are also recognised pollution sources. The bioavailability of these toxic compounds, and more importantly their potential biomagnification along food chains, could affect aquatic communities persistently exposed to road runoff. Several internationally approved abatement technologies are available for the management of road runoff on new motorway schemes. Recent studies conducted in Cork and Dublin, Ireland demonstrated the efficacy of infiltration trenches as abatement technologies in the removal of both heavy metals and PAHs prior to discharge; the technology was however inefficient in mitigating first flush events. Gully traps with sedimentation chambers, another technology investigated, demonstrated to have a substantially lower removal potential but appeared to be more effective in attenuating surges of contaminants attributed to first flush events. Consequently the employment of combined abatement techniques could efficiently minimise deviations from required effluent concentrations. The studies determined a relatively stationary accumulation of heavy metals and PAHs in sediments close to the point of discharge with a rapid decline in concentration in nearby downstream sediments (<50m). Further, Microtox® Solid Phase testing reported a negligible impact on assemblages exposed to contaminated sediments for all sites investigated. This paper describes pollutant loading from road runoff and mitigation measures from a freshwater deterioration in a water quality perspective. The results and analysis of field samples collected adjacent to a number of roads and motorways in Ireland is also presented. Finally sustainable drainage systems, abatement techniques and technologies available for onsite treatment of runoff are presented to improve and mitigate impacts of vehicular transport on the environment.

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Tese de doutoramento, Geografia (Geografia Física), Universidade de Lisboa, Instituto de Geografia e Ordenamento do Território, 2014

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El proceso administrativo y de compras de OPL Carga tiene algunas falencias entre ellas: fallas en la Comunicación entre el personal operativo, no se realizan llamadas internas usando con frecuencia el email, produciendo la saturación de solicitudes las cuales terminan sin ser resueltas en cuanto a roles se refiere, no hay enfoque de procesos en vista que no se tiene claras las tareas de cada cargo, adicionalmente no hay claridad en los subprocesos, perjudicando el proceso con el aumento de costos, pérdida de tiempo, las responsabilidades de los funcionario no todas las veces se ejecutan en el tiempo asignado, el liderazgo compartido presenta ambigüedades. Objetivos: Definir el trabajo en equipo en el proceso administrativo y de compras en OPL carga de Bucaramanga. La investigación que a realizar es de tipo descriptivo, busca descubrir las falencias o características que permiten diseñar y desarrollar un modelo de solución para los problemas del equipo de OPL Carga S.A.S. Materiales y métodos: La investigación efectuada es de tipo descriptivo, el objetivo es definir el modelo del trabajo en equipo y describir las falencias en el proceso administrativo y de compras en OPL carga de Bucaramanga, que permitan obtener un diagnóstico integral que conlleve a la implementación de estrategias de solución. Resultados: Se identificaron las falencias en los siguientes aspectos: Variable comunicación, rendimiento, destrezas complementarias, propósito significativo y meta específicas de los funcionarios en OPL carga sección administrativa. Conclusiones: El modelo de trabajo en equipo que OPL aplica es jerárquico, en el que se ofrece estabilidad, seguridad, se toman decisiones en forma piramidal, mediante la planeación de tareas, la colaboración, igualdad y respeto por los miembros, trabajando en pro de la solución de problemas. Se construyó un plano conceptual que permitió exponer la interpretación que la estudiante tiene de las teorías, investigaciones y antecedentes válidos para la comprensión del problema investigado. Área comunicacional: Coordinar acciones tendientes para que los funcionarios respondan a tiempo los emails atenientes a su trabajo. Área condiciones de trabajo: Clarificar y diseñar las reglas de comportamiento al interior de los equipos de trabajo que redunden en el mejoramiento del mismo y la búsqueda de soluciones oportunas. Área metas específicas: Procurar mediante auditorías el cumplimiento de las metas y objetivos propuestos por cada equipo de trabajo.

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Here, we analyze the complete coding sequences of all recognized tick-borne flavivirus species, including Gadgets Gully, Royal Farm and Karshi virus, seabird-associated flaviviruses, Kadam virus and previously uncharacterized isolates of Kyasanur Forest disease virus and Omsk hemorrhagic fever virus. Significant taxonomic improvements are proposed, e.g. the identification of three major groups (mammalian, seabird and Kadam tick-borne flavivirus groups), the creation of a new species (Karshi virus) and the assignment of Tick-borne encephalitis and Louping ill viruses to a unique species (Tick-borne encephalitis virus) including four viral types (i.e. Western Tick-borne encephalitis virus, Eastern Tick-borne encephalitis virus, Turkish sheep Tick-borne encephalitis virus and Louping ill Tick-borne encephalitis virus). The analyses also suggest a complex relationship between viruses infecting birds and those infecting mammals. Ticks that feed on both categories of vertebrates may constitute the evolutionary bridge between the three distinct identified lineages.

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Este estudo teve como principal objetivo avaliar os estados de erosão acelerada do solo da microbacia hidrográfica do córrego da Fazenda Glória, Município de Taquaritinga, SP. Para tanto, foram utilizadas técnicas de sensoriamento remoto e geoprocessamento para análise em fotografias aéreas verticais, coloridas, na escala aproximada de 1:30.000, do aerolevantamento realizado pela BASE - Aerolevantamentos, dos anos de 1983 e 2000. Os processos erosivos foram identificados nas fotografias aéreas da microbacia hidrográfica e observados nas visitas em campo. Como resultado, o aspecto erosivo predominante na área foi o 3, áreas onde ocorria erosão com intensidade que afetava severamente a cobertura vegetal. O estado de erosão 2, com média intensidade, aumentou durante o período analisado. Este trabalho servirá de base para implementar programas de preservação de recursos naturais e de manejo conservacionista na microbacia.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This study aimed to determine how the richness and composition of ant species behaves with changes in the recovery process of a gully erosion. The study area has 0.9 hectares subdivided into three sections called sector: A, B and C. For the definition of the sectors, erosive and natural restoring were taken as the base level of activity. Four transects were laid systematically throughout the area and surrounding compound with forest and grassland. Each transect had three pitfall trap ten meters apart from each other, with catches of ants were held in rainy and dry seasons. Analysis of variance was applied to compare the number of ant species per plot captured and Scott-Knott test 5% for comparison of means. To verify the similarity of species between environments it was performed an analysis of similarity (ANOSIM) and ordering of environments a Nonmetric Multidimensional Scaling (NMDS). We captured 74 species of ants inside and around the gully erosion. The more degraded environment and initial stage of regeneration, showed greater richness of ant species. The composition of ant species was different between the recovery environments and around. The parameters of ant communities analyzed, richness and composition species were influenced by the regeneration of the area, indicating that ants can be used as bioindicators of gullies recovery.