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The Use of Chemical Hydrographs in Groundwater Quality StudiesSchmidt, Kenneth D. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / High nitrates in drinking water are significant in relation to an infant disease, methemoglobinemia, and the U.S. public health service has set a limit of 45 ppm for human consumption. This paper illustrates how chemical hydrographs were used in a study of nitrates in the groundwater of the Fresno-Clovis metropolitan area (F.C.M.A.) of semiarid central California. The area comprises about 145 square miles, with a population of 310,000. Urban water use is entirely derived from wells, whereas the surrounding agriculture relies on surface and ground water. In 1965, the California department of water resources noted nitrate concentrations in the F.C.M.A. were exceeding the safe limit. A number of sources of error in chemical analyses of water quality are noted. A measure of the accuracies of analyses and a method of double-checking anomalous results is furnished by plotting chemical hydrographs of individual wells. Seasonal changes in nitrate were consistent for many parts of the area, and were related to hydrogeologic factors and parameters directly affecting nitrification. Nitrate hydrographs were monitored by chloride hydrographs. The highest nitrate concentrations were in the shallower parts of the aquifer, and well deepening and changes in water level, pumping patterns and recharge rates complicated interpretations. However, the hydrographs helped to pinpoint the source of nitrate in areas where several possible sources were present.
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Increasing Forage Production on a Semiarid Rangeland WatershedTromble, J. M. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Two native grass species, blue grama and sidecoats, were successfully seeded on a semiarid rangeland on the walnut gulch experimental watershed in southeastern Arizona. Optimum seeding dates selected were those within the time period most likely to receive precipitation, and grass stands were established in two successive years with average rainfall. Shrubs were killed by root-plowing at a depth of 14 inches, a procedure which was more than 95% successful in controlling sprouting shrubs. Forage production measurements taken on nm-28 sideoats and Vaughn sideoats showed a yield of 1,950 and 2,643 pounds of forage per acre, respectively, for the 2 years following the seeding, whereas untreated sites produced 23 and 25 pounds per acre of forage. Results indicate that success in establishing a stand of native grass is increased through use of existing hydrologic data.
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A Deterministic Model for Semi-Arid CatchmentsNnaji, S., Davis, D. R., Fogel, M. M. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Semiarid environments exhibit certain hydrologic characteristics which must be taken into consideration for the effective modeling of the behavior of catchments in these areas. Convective storms, which cause most of the runoff, occur in high intensity and short duration during the summer months and are highly localized so that only a small portion of the catchment actually contributes flow to the storm hydrograph. Also, streams in semiarid catchments are ephemeral with flow occurring only about 1 percent of the time. This study attempts to develop a simple synthetic catchment model that reflects these features of the semiarid environment and for which (1) the simplifying assumptions do not preclude the inclusion of the important components of the runoff process, and (2) parameters of the equations representing the component processes have physical interpretation and are obtainable from basin characteristics so that the model may be applicable to ungaged sites. A reductionist approach is then applied in which the entire catchment is subdivided into a finite number of meshes and the various components of the runoff phenomenon are delineated within each mesh as independent functions of the catchment. Simplified forms of the hydrodynamic equations of flow are used to route flow generated from each mesh to obtain a complete hydrograph at the outlet point.
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Effects of Brush to Grass Conversion on the Hydrology and Erosion of a Semiarid Southwestern Rangeland WatershedSimanton, J. R., Osborn, H. B., Renard, K. G. 16 April 1977 (has links)
From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / Increased nutritional and economic demands for agricultural products have dictated the need for greater and more efficient use of western grass forage. Vegetation manipulation is the quickest and most economical means of increasing forage. However , the hydrologic effects must be taken into consideration before embarking on a large scale vegetation manipulated program. This study discusses the hydrologic and erosion changes measured from a 110-acre semiarid watershed which was converted from brush to grass by root plowing and seeding. Significant changes were observed in rainfall-runoff relationships as average summer runoff was considerably in excess of predictions. Sediment yield also varied, and both of these results were tied to the change in vegetative cover and post conversion rainfall conditions.
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Geomorphic Features Affecting Transmission Loss PotentialWallace, D. E., Lane, L. J. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Water yield studies and flood control surveys often necessitate estimating transmission losses from ungaged watersheds. There is an immediate need for an economical method that provides the required accuracy. Analysis of relations between stream order, drainage area, and volume of channel alluvium existing in the various orders is one means of estimating loss potential. Data needed for the stream order survey are taken from aerial photos. Stream order is analyzed using stereophoto maps. Stream lengths taken from the maps are combined with average channel width and depth data (determined by prior surveys) to estimate volumes of alluvium involved. The volume of channel alluvium in a drainage network is directly related to the stream order number of its channels. Thus, a volume of alluvium within a drainage network (with a known transmission loss potential) may be estimated by knowing the order of each length of channel and the drainage areas involved. In analyzing drainage areas of 56-mi² or less, 70 to 75 percent of the total drainage network length is contained within first and second order channels; yet, these constitute less than 10 percent of the total transmission loss potential of the areas. Analysis of stream order and drainage area versus volume of alluvium relations allows preliminary estimates of transmission loss potential to be made for ungaged areas.
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Da experimentação social ao "experimentalismo institucional" : Trajetórias de relações entre Estado e sociedade civil: Experiências no Semi-Árido. / From social experimentation to "institutional experimentalism": Trajectories of relations between State and civil society: Experiences in the Semi-Arid. / De l'expérimentation sociale à l '"expérimentalisme institutionnel": trajectoires des relations entre État et société civile: expériences dans les pays semi-arides.DINIZ, Paulo Cesar Oliveira. 25 October 2018 (has links)
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Previous issue date: 2007-10-02 / Este trabalho analisa um processo de “experimentalismo institucional” instituído no Governo Lula com o objetivo de fundar um novo paradigma na relação entre Estado e sociedade civil, seja no sentido de alargar a relação ou seja na intenção de aprofundar as mudanças ocorridas no âmbito relacional. Dois aspectos caracterizam um experimentalismo institucional: a decisão do governo em repensar os mecanismos de elaboração e implementação de políticas públicas e, ao mesmo tempo, a iniciativa
governamental de buscar se apropriar e fortalecer as experiências bem sucedidas
no campo da sociedade civil, passando a referenciar novas políticas. E Dois casos de experimentalismo institucional serão analisados. No primeiro, o experimentalismo se funda em torno da política de segurança alimentar do governo federal e das experiências de convivência com o sem-árido, estas desenvolvidas pela Articulação do Semi-Árido Paraibano. No segundo caso, o experimentalismo é instituído a partir da implantação da política governamental de desenvolvimento territorial. Nos territórios, atores sociais e
governos interagem num processo de aprendizagem no sentido de estabelecer
concertações, compartilhar identidades e compromissos mútuos. Finalmente, o texto apresenta algumas considerações sobre os dois casos de experimentalismo institucional e sua capacidade para alargar as relações entre Estado e sociedade civil e para aprofundar as mudanças pretendidas e os compromissos assumidos nessa trama relacional. Além disso, sugere como esses experimentalismos contribuíram para o estabelecimento de um “novo projeto” de agricultura familiar no país. / This thesis analyses a process of “institutional experimentalism” that was implement by Lula’s1 Government, in order to establish a new paradigm in the relationship between the State and Civil Society, both to broaden the scope and deepen the changes that occurred in this relationship. Two aspects characterize this “institutional experimentalism”: firstly, the
government’s decision to review the elaboration and implementation mechanisms of public policies and, secondly, the government’s initiative to incorporate, and strengthen, the successful Civil Society initiatives, using them as references for new policies. Two cases of “institutional experimentalism” are discussed. In the first one, the “experimentalism” is established around the Federal Government’s food security policy and the initiatives based on the idea of “living with the semi-arid environment”2 developed by the Paraíba Semi-Arid Region Network. In the second case, the “experimentalism” concerns the implementation the governmental policy of territorial development. In the territories, social actors and government bodies interact in a learning process that tries to establish negotiation, and share identities and bilateral commitments. Finally, the thesis presents some concluding remarks on the two cases of “institutional experimentalism” and their capacity to reinforce the relationship between the State and Civil Society and to consolidate the intended changes and the commitments that were set up in this process. Moreover, it also comments on how this “experimentalism” has contributed towards the establishment of a
“new project” for the country’s family farmers. / Le présent travail analyse un processus d' espérimentalisme institutionnel, institué par le Gouvernement Lula dans le but de créer un nouveau paradigme dans la relation entre l'Etat et la societé civile, que ce soit dans le sens d’élargir cette relation ou que ce soit dans le but d’approfondir les changements qui ont eu lieu dans le domaine relationnel. Deux aspects caractérisent cet expérimentalisme institutionnel : la décision du
gouvernement de repenser les mécanismes d’élaboration et d’implantation de
politiques publiques et, en même temps, l’initiative gouvernementale de chercher
à s’approprier des expériences réussies dans le champ de la société civile, et à
les renforcer pour qu’elles servent de référence pour de nouvelles politiques. Deux cas d’expérimentalisme institutionnel seront analysés. Dans le premier, l’expérimentalisme s’exerce à propos de la politique de sécurité alimentaire du gouvernement fédéral et sur la base des expériences bien réussies de « convivence » dans la région semi-aride, expériences menées par l’Articulation du Semi-Aride de la Paraíba. Dans le second cas, l’expérimentalisme s’institue à partir de l’implantation de la politique gouvernementale de
développement territorial. Dans les territoires, acteurs sociaux et gouvernements
dialoguent dans un processus d’apprentissage visant à établir des arrangements,
partager des identités et des engagements mutuels. Finalment, le texte présente quelques considérations sur les deux cas d’expérimentalisme institutionnel et leur capacité d’élargir les relations entre Etat et société civile, et d’approfondir les changements recherchés et les engagements assumés dans cette trame relationnelle. En outre, il suggère que
ces expérimentalismes ont contribué à établir um « nouveau projet » d’agriculture familiale dans le pays.
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Análise geoambiental em unidades de conservação de proteção integral no semiárido sergipanoSouza, Heloísa Thaís Rodrigues de 16 December 2016 (has links)
Historically, the northeastern forest activity has been characterized by a predatory
exploitation model of natural ecorecursos, notably from the caatinga (ecosystem rich in
biodiversity), by the disorganization of production and by the low valorization and
diversification of the forest products of the semiarid, limited mainly to firewood And
coal. Nonetheless, this activity contributes significantly to regional development. In
order to protect biodiversity in the semi-arid region of Sergipe, it is necessary to create
planning and management mechanisms, with the involvement of the entire society.
Among these mechanisms exists as a public policy in situ conservation, in Brazil, one of
the main strategies is the creation of Conservation Units (CUs). In this context, the
present thesis results in the evaluations of the dynamics of the forest fragments in
Conservation Integrated Units in the Semi-Arid Sergipano, promoting concrete
recommendations for management purposes and consequently subsidies for effective
and / or elaboration of the management plan of the same, Basic assumption of the
environmental sustainability of these remnants, verified through environmental
indicators (biotic and abiotic). In this sense, the objective of this research was to analyze
the effects of the implantations of the Conservation Units of Integral Protection of the
State of Sergipe, the conservation of the forest fragments in the Semi - arid, evaluating
the socio - environmental aspects of the same through sustainability indicators. Thus,
this research made possible the necessary elements to characterize the biotic and abiotic
situation of the remaining Caatinga forest remnants in the State, due to the creation of
the CUs, looking at the environmental problems resulting from degradation processes
and inadequate management that contributed to the current Framework, pointing out
possibilities of actions for their better conservation and sustainability. The results of the
analysis of the indicators (biotic and abiotic) indicate different levels of anthropization
of the caatinga, which result in geoenvironments that have different regeneration
capacities, even being within the macro vegetative complex. Thus, monitoring has
become important to create subsidies for the management of the caatinga to be carried
out according to the fragilities of each micro-environment. In addition, the sustainable
forest management of the forest stands out from the use of the phytotherapeutic
potential of the vegetal species of the sergipana caatinga. / Históricamente, la actividad forestal nordestina se ha caracterizado por un modelo de
explotación predatoria de los ecorecursos naturales, principalmente provenientes de la
caatinga (ecosistema rico en biodiversidad), por la desorganización de la producción y
por la baja valorización y diversificación de los productos forestales del semiárido,
limitados principalmente a leña Y el carbón. A pesar de ello, esta actividad contribuye
significativamente al desarrollo regional. Para que haya protección de la biodiversidad
en el semiárido sergipano, es necesaria la creación de mecanismos de planificación y
gestión, con la participación de toda la sociedad. Entre estos mecanismos existe como
política pública la conservación in situ, en Brasil, una de las principales estrategias
consiste en la creación de Unidades de Conservación (UC's). En este contexto, la
presente tesis resulta en las evaluaciones de las dinámicas de los fragmentos forestales
en UC's de Protección Integral en el Semiárido Sergipano, promoviendo
recomendaciones concretas para fines de gestión y consecuentemente subsidios para
efectivización y / o elaboración del plan de manejo de las mismas, teniendo por Premisa
básica la sostenibilidad ambiental de estos remanentes, verificados a través de
indicadores ambientales (bióticos y abióticos). En ese sentido, esa investigación
objetivó analizar los efectos de las implantaciones referentes a las Unidades de
Conservación de Protección Integral del Estado de Sergipe, la conservación de los
fragmentos forestales en el Semiárido, evaluando los aspectos socioambientales de los
mismos a través de indicadores de sustentabilidad.
. Así, esta investigación viabilizó elementos necesarios para caracterizar la situación
biótica y abiótica de los remanentes forestales de la Caatinga aún existentes en el
Estado, por cuenta de la creación de las UC's, vislumbrando los problemas ambientales
resultantes de procesos de degradación y manejo inadecuado que contribuyeron al
actual , Que apunta a posibilidades de acciones para su mejor conservación y
sostenibilidad. Los resultados de los análisis de los indicadores (bióticos y abióticos)
indican diferentes niveles de antropización de la caatinga, que resultan en geoambientes
que poseen distintas capacidades de regeneración, aun estando dentro del macro
complejo vegetacional. Así, el monitoreo se hizo importante para crear subsidios para
que el manejo de la caatinga sea realizado de acuerdo con las fragilidades de cada micro
ambiente. Además, se destaca el manejo forestal sustentable del bosque a partir de la
utilización del potencial fitoterápico de las especies vegetales de la caatinga sergipana. / Historicamente, a atividade florestal nordestina tem se caracterizado por um modelo de
exploração predatório dos ecorecursos naturais, notadamente oriundos da caatinga
(ecossistema rico em biodiversidade), pela desorganização da produção e pela baixa
valorização e diversificação dos produtos florestais do semiárido, limitados
principalmente a lenha e ao carvão. Apesar disso, essa atividade contribui
significativamente para o desenvolvimento regional. Para que haja a proteção da
biodiversidade no semiárido sergipano, é necessária a criação de mecanismos de
planejamento e gestão, com o envolvimento de toda a sociedade. Dentre esses
mecanismos existe como política pública a conservação in situ, no Brasil, uma das
principais estratégias consiste na criação de Unidades de Conservação (UC´s). Neste
contexto, a presente tese resulta nas avaliações das dinâmicas dos fragmentos florestais
em UC´s de Proteção Integral no Semiárido Sergipano, promovendo recomendações
concretas para fins de gestão e consequentemente subsídios para efetivação e/ou
elaboração do plano de manejo das mesmas, tendo por premissa básica a
sustentabilidade ambiental desses remanescentes, verificados através de indicadores
ambientais (bióticos e abióticos). Nesse sentido, essa pesquisa objetivou analisar os
efeitos das implantações referentes às Unidades de Conservação de Proteção Integral do
Estado de Sergipe, a conservação dos fragmentos florestais no Semiárido, avaliando os
aspectos socioambientais dos mesmos através de indicadores de sustentabilidade.
. Assim, esta pesquisa viabilizou elementos necessários para caracterizar a situação
biótica e abiótica dos remanescentes florestais da Caatinga ainda existentes no Estado,
por conta da criação das UC´s, vislumbrando os problemas ambientais decorrentes de
processos de degradação e manejo inadequado que contribuíram para o atual quadro,
apontando possibilidades de ações para a sua melhor conservação e sustentabilidade. Os
resultados das análises dos indicadores (bióticos e abióticos) indicam diferentes níveis
de antropização da caatinga, que resultam em geoambientes que possuem distintas
capacidades de regeneração, mesmo estando dentro do macro complexo vegetacional.
Assim, o monitoramento fez-se importante para criar subsídios para que o manejo da
caatinga seja realizado de acordo com as fragilidades de cada micro ambiente. Ademais,
destaca-se o manejo florestal sustentável da floresta a partir da utilização do potencial
fitoterápico das espécies vegetais da caatinga sergipana.
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Applicability of the Universal Soil Loss Equation to Semiarid Rangeland Conditions in the SouthwestRenard, K. G., Simanton, J. R., Osborn, H. B. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / An erosion prediction method that has recently received wide attention in the United States is the universal soil loss equation which is given as: a=rklscp. Where a = estimated soil loss (tons/acre/year), r = a rainfall factor, k = a soil erodibility factor, l = a slope length factor, s = a slope gradient factor, c = a cropping-management factor, and p = an erosion control practice factor. Data collected on the walnut gulch experimental watershed in southeastern Arizona were used to estimate these factors for semiarid rangeland conditions. The equation was then tested with data from watersheds of 108 and 372 acres. The predicted value of annual sediment yield was 1.29 tons/acre/year as compared with an average 1.64 tons/acre/year for 4 years of data for the 108-acre watershed, and a sediment yield of 0.39 tons/acre/year was predicted for the 372-acre watershed as compared with the measured value of 0.52 tons/acre/year. Although good agreement was noted between predicted and actual sediment yield, additional work is needed before the equation can be applied to other areas of the southwest.
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