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Oportunidades y desafíos para la protección del piedemonte andino de Santiago : una perspectiva desde la gobernanza urbana / Opportunities and challenges for the protection of the andean piedmont of Santiago. A perspective from the urban governanceGaldámez Roco, Elizabeth January 2016 (has links)
Memoria para optar al Título Profesional de Ingeniero en Recursos Naturales Renovables / La transformación de las áreas naturales a otros usos o coberturas es una de las alteraciones más importantes que ha provocado el ser humano, pues modifica entre otras cosas, la estructura y funcionamiento de los ecosistemas. Uno de los hechos más relevantes es la expansión de suelo urbano sobre áreas adyacentes a hotspot de biodiversidad. Es el caso de la ciudad de Santiago, que desde mediados de siglo pasado ha crecido sobre el Piedemonte Andino de Santiago. La dicotomía entre la expansión de las ciudades y la protección de estos ecosistemas exige una nueva forma de planificar las ciudades, que requiere comprender que en estas zonas confluyen diversos intereses y se encuentran en constante tensión. El reconocimiento de la complejidad de los actores involucrados conlleva la necesidad de analizar las condiciones actuales de interacción entre los actores que indicen sobre estas áreas naturales. La gobernanza ofrece un marco de análisis acorde a estas necesidades. A partir de este enfoque en la investigación se buscaron oportunidades y desafíos para la protección del Piedemonte analizando los arreglos institucionales formales (leyes, ordenanzas, procedimientos formales, políticas, planes, entre otros), e informales (valores, creencias, pautas de comportamiento, entre otros) mediante las cuales se preparan, adoptan y ejecutan las decisiones en la esfera pública.
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The carbon balance of Atriplex vesicaria / by Desmond F. ColemanColeman, Desmond Francis January 1982 (has links)
Typescript (photocopy) / x, 210 leaves, [2] leaves of col. plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1982
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Evaluación del uso de atriplex nummularia con la aplicación de enmiendas húmicas para la fitoestabilización de relaves minerosLoch Arellano, Bruno Nicolas 11 1900 (has links)
Químico Ambiental / La minería del cobre es una actividad económica muy importante para el país, sin embargo, presenta diversos riesgos ambientales, principalmente asociados a la disposición de relaves mineros. Uno de los métodos utilizados en la remediación de estos relaves es la fitoestabilización, que se enfoca en generar una cobertura vegetal que permita la estabilización y contención del relave.
El presente trabajo tiene por objetivo evaluar la capacidad de Atriplex nummularia, en conjunto con las enmiendas orgánicas Perl Humus y compost, para la fitoestabilización de un relave minero de Chile (Tranque de Relaves Ovejería), con respecto a Cu, Mo y S. Para esto se implementó un ensayo en invernadero con macetas con tres sustratos: T1 (relave), T2 (Relave + Perl Humus) y T3 (Relave + compost). La proporción de la enmienda orgánica fue de 5% m/m. El sustrato fue caracterizado para: CE, pH, N, P, K, entre otros. La determinación de biomasa seca de tejido vegetal (aéreo y radicular) y de las concentraciones de Cu, Mo y S, tanto en sustrato como en tejido vegetal, se realizó a los 60 y 120 días. Con estos resultados, se determinó el índice de translocación (Ti) y el factor de bioconcentración (FBC).
Al final del ensayo, se encontró que la biomasa aérea y radicular fue mayor en los tratamientos con enmiendas orgánicas, siendo el tratamiento con Perl Humus (T2) en el que se generó la mayor biomasa de tejido aéreo. Las concentraciones de Cu (7,3–10,2 mg kg-1) y Mo (1,0–3,0 mg kg-1) en tejido aéreo de A. nummularia no presentaron niveles tóxicos (Cu>20 mg kg-1; Mo>1 mg kg-1), excepto en el tratamiento con compost (T3), en que los niveles de Mo fueron 10,2 mg kg.1. En cada tratamiento, las concentraciones de S en tejido aéreo (7319–24452 mg kg-1) superan los valores encontrados en suelos agrícolas. En relación con el índice de translocación (Ti), Cu (0,026–0,19), Mo (0,27–1,11) y S (0,25–0,93) mostraron valores menores a 1 en todos los tratamientos, excepto para Mo en relave (T1). Los valores más bajos de Ti fueron para el tratamiento con Perl Humus. Esto indicaría que en este tratamiento A. nummularia presenta una mayor acumulación de Cu, Mo y S en raíz que en los otros tratamientos, propiedad que favorece la fitoestabilización del relave. Respecto al factor de bioconcentración (FBC), en todos los tratamientos y tanto
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para tejido aéreo como para raíz, los valores para Cu (0,0059-0,22) y Mo (0,03-0,36) fueron menores a 1 y los valores para S fueron mayores a 1 (9-57,5). Los resultados del factor de bioconcentración indican que el elemento que más se absorbe por el tejido vegetal es S, siendo el tratamiento con Perl Humus en el que se observa la mayor absorción.
Mediante el análisis de los resultados, es posible establecer que la adición de enmiendas orgánicas al relave minero aumenta el potencial de fitoestabilización de A. nummularia, respecto a Cu, Mo y S. La enmienda Perl Humus presentó ventajas sobre el compost, principalmente para la acumulación en raíz de Cu y S. Por esto, se podría recomendar el uso de esta especie vegetal ayudada por la enmienda orgánica Perl Humus para la estabilización química de relaves con alto contenido de Cu y S. / Copper mining is a very important economic activity for the country, however, it presents several environmental risks, mainly associated with the disposal of mine tailings. One of the methods used in the remediation of these tailings is the phytostabilization, which focuses on generating a vegetative cap that allows the stabilization and containment of the tailings.
The present work aims to evaluate the capacity of Atriplex nummularia, in conjunction with the organic amendments Perl Humus and compost, to achieve the phytostabilization of a Chilean mine tailings (Tranque de Relaves Ovejería), regarding Cu, Mo and S. For this, a greenhouse experiment was implemented with three substrata: T1 (Tailings), T2 (Tailings + Perl Humus) and T3 (Tailings + compost). The proportion of the amendments was 5% w/w. The substrata was characterized for: EC, pH, N, P, K, among others. The determination of dry biomass of vegetal tissue (aerial and root) and the concentration of Cu, Mo and S, both in substrate and in plant tissue, was carried out at 60 and 120 days. With these results, the translocation index (Ti) and the bioconcentration factor (FBC) were determined.
At the end of the experiment, it was found that the aerial and root biomass was higher in the treatments with organic amendments, being the treatment with Perl Humus (T2) in which the highest biomass of aerial tissue was generated. The concentration of Cu (7,3–10,2 mg kg-1) and Mo (1,0–3,0 mg kg-1) in aerial tissue of A. nummularia did not present toxic levels (Cu>20 mg kg-1; Mo>1 mg kg-1), except for the treatment with compost (T3), in which the levels of Mo were 10,2 mg kg.1. In each treatment, the concentrations of S in aerial tissue (7319–24452 mg kg-1) excedes the values found in agricultural soils. Regarding the translocation index (Ti), Cu (0,026–0,19), Mo (0,27–1,11) and S (0,25–0,93) showed values lower than 1 in all treatments, except for Mo in tailings (T1). The lowest Ti values were for the Perl Humus treatment. This would indicate that in this treatment A. nummularia presents a higher acumulation of Cu, Mo and S in root than in the other treatments, property that favors the phytostabilization of the tailings. Concerning the bioconcentration factor (FBC), in all the treatments and for both aerial and
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root tissue, the values for Cu (0,0059-0,22) and Mo (0,03-0,36) were less than 1 and the values for S were greater than 1 (9-57,5). The results of the bioconcentration factor indicate that the element that is more absorbed by the plant tissue is S, being the treatment with Perl Humus in which the greater absorption is observed.
By analyzing the results it is possible to establish that the adition of organic amendments to the mine tailings increases the phytostabilization potential of A. nummularia, regarding Cu, Mo and S. The amendment Perl Humus showed advantages over compost, mainly for the acumulation of Cu and S in roots. For this reason, the use of this species, aided by the organic amendment Perl Humus, could be recommended for the chemical stabilization of mine tailings with high content of Cu and S.
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Uso de aguas servidas tratadas en cultivos de atriplex con fines energéticos / Treated wastewater use on atriplex crops for energy purposeFigueroa Parraguez, Jorge Andrés January 2016 (has links)
Memoria para optar al título profesional de Ingeniero en Recursos Naturales Renovables / Las zonas áridas de Chile corresponden aproximadamente al 40% del territorio nacional, y están compuestas por suelos potencialmente productivos no utilizados. Las potenciales áreas para la expansión de cultivos energéticos, no representan competencia para los cultivos con fines alimenticios, debido a que son suelos marginales y áridos, subutilizados debido a la degradación que poseen, inviables para la producción agroalimentaria. El uso de aguas servidas para el riego de cultivos energéticos contribuye a la disminución de la demanda de agua de riego frente a la escasez. Las especies del género Atriplex representan una opción para la producción de biomasa para bioenergía. Esta memoria determinó el efecto del riego con aguas servidas tratadas sobre el crecimiento y desarrollo de A. nummularia, A. halimus y A. canescens, con fines bioenergéticos.
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THE PHOTOSYNTHESIS OF TWO ATRIPLEX SPECIES AS A FUNCTION OF SALINITY.Gast, Timothy Curtis. January 1983 (has links)
No description available.
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efeito da aplica??o de uma solu??o salina no crescimento e na composi??o qu?mica da atriplex nummulariaAraujo, Eliane Gon?alves de 06 August 2009 (has links)
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Previous issue date: 2009-08-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aimed to analyze the effect of a saline solution on growth and chemical composition of Atriplex nummularia, shrubby plant, absorbing salts used in the diet of animals and the management of water and saline soils. These plant seedlings
were planted and grown in a reserved area at the Federal University of Rio Grande do Norte. The plantation was divided into two blocks, in which one of them was irrigated with saline solution with a concentration of 2840 mgL-1 of NaCl and the second group was irrigated with drinking water. After six months, the plants were collected, harvested and divided into three parts: leaf, thin and thick stem. Monthly, dimension
measurements were carried out for cataloging the growth of Atriplex. Ion Chromatography (IC) and Optical Emission Spectroscopy Inductively Coupled Plasma (ICP-OES) were used to analyze the chemical composition of the partition plant parts.
The results of these analyses revealed that an absorption process of anions and cations by Atriplex nummularia plant during its growth was achieved, in particular by a higher
concentration of sodium and chloride ions. Scanning electron microscopy images showed and confirmed the presence of small crystals on the leaf surface. Electrical conductivity and pH measurements of the aerial parts of the plant were carried out and these results showed that the leaf is the plant part where there is a largest concentration of ions. In addition, measurements of specific surface were obtained from irrigated
plants with saline solution, achieving higher surface area, in all cases. Plant dimensions obtained monthly showed that the plants irrigated with water grew 5% more than those plants irrigated with saline solution. Based on results obtained, Atriplex plant showed a higher potential to survive and adapt to environments (aquatic or geological) with high levels of salinity and this property can be used as a tool for removing salts/metals from industrial contaminated soils and effluents. / O presente estudo teve como objetivo analisar o efeito da aplica??o de uma solu??o salina no crescimento e na composi??o qu?mica da Atriplex nummularia, planta arbustiva, absorvedora de sais utilizada na dieta de animais e no manejo de ?guas e solos salinos. Mudas desta erva foram plantadas e cultivadas no Horto da Universidade Federal do Rio Grande do Norte. A planta??o foi dividida em dois blocos, no qual um
deles foi irrigado com solu??o salina com concentra??o de 2840 mgL-1 de cloreto e o outro irrigado com ?gua pot?vel. Ap?s seis meses do plantio as plantas foram colhidas e dividas em tr?s partes: folha, caule fino e caule grosso. O crescimento da Atriplex foi avaliado atrav?s de medidas mensais. Para a caracteriza??o qu?mica fez-se necess?rio o uso de t?cnicas anal?ticas como: Cromatografia de ?ons (IC) e Espectroscopia de
Emiss?o ?ptica por Plasma Indutivamente Acoplado (ICP-OES). Os resultados dessas an?lises destacaram a diversidade de ?nions e c?tions absorvidos pela planta durante seu processo evolutivo, apresentando em especial uma maior concentra??o dos ?ons s?dio e cloreto. A Microscopia Eletr?nica de Varredura identificou a presen?a de pequenos cristais na superf?cie da folha. An?lises de condutividade el?trica das partes a?reas da
planta foram realizadas juntamente com medidas do potencial hidrogeni?nico e essas mostraram que na folha encontram-se as maiores concentra??o de ?ons. Medidas da ?rea superficial espec?fica das plantas irrigadas com solu??o salina apresentaram maior ?rea superficial. As medidas mensais realizadas durante todo o cultivo mostraram que as plantas irrigadas com ?gua pot?vel se desenvolveram 5% a mais do que as plantas cultivadas com solu??o salina. Com base em todos os resultados obtidos durante o estudo foi conclu?do que a Atriplex ? uma planta que apresenta potencialidade em
sobreviver e adaptar-se a ambientes salinos, podendo ser utilizada como uma fonte absorvedora de sais dos solos contaminados por efluentes resultantes de processos
industriais nos quais tem a ?gua salina como produto final de seus processos.
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Seasonal Patterns of Photosynthesis and Respiration in Atriplex confertifolia and Ceratoides lanataWhite, Richard S. 01 May 1976 (has links)
Net photosynthesis and dark respiration studies were conducted on Atriplex confertifolia (Torr. and Frem.) S. Wats and Ceratoides lanata (Pursh) J.T. Howell under field and laboratory conditions. These woody species are commonly found in salt desert shrub communities of the Intermountain West. During these investigations, the effects of air temperature, plant moisture stress, soil water potential, irradiation, and plant phenological status were examined with respect to their influence on carbon dioxide (CO2 ) exchange.
Intensive field studies were carried out between April and October. This interval corresponded to the major period of physiological activity in both species. The factors of moisture stress and phenological status appeared to regulate photosynthesis and respiration on a seasonal basis. They set the limits within which daily CO2 exchange could take place. Diel patterns of CO2 exchange were primarily controlled by prevailing temperature and irradiation. Irradiation was more critical during the spring, and temperature became more limiting in the summer.
Two alternate photosynthetic strategies of dealing with existing harsh environmental conditions appeared to have evolved in Atriplex confertifolia and Ceratoides lanata. Atriplex confertifolia exhibited an endurance strategy whereby it continued moderate rates of photosynthesis throughout the season. Ceratoides lanata, in contrast, completed the majority of its net assimilation in the spring; then it was relatively inactive when moisture stress became great. These differences seemed to be correlated with water use efficiencies of both species.
Rates of net photosynthesis were greatest during the spring in both species. At that time CO2 fixation in Ceratoides lanata exceeded that of Atriplex confertifolia. Later in the year, photosynthetic rates were reduced; and the assimilation rate of Atriplex confertifolia was greater than that observed in Ceratoides lanata. These seasonal patterns of CO2 exchange offered an insight into differences between species using different assimilation pathways. Atriplex confertifolia utilizes the dicarboxylic acid pathway (C4) for carbon fixation, while Ceratoides lanata uses the pentose pathway (C3). Since both species can coexist in the same reasonably stable community, it appeared that both carboxylation pathways were efficient with respect to prevailing environmental conditions.
Atriplex confertifolia had lower net assimilation rates than C4 species from warmer climates. It carried on moderate rates of photosynthesis at low temperature (5 to 10 C), and it had relatively low thermal optima (15 to 27 C) for net photosynthesis. An acclimative shift in temperature optima was also noted. This photosynthetic pattern seemed to be related to the climatic conditions under which Atriplex confertifolia evolved.
Ceratoides lanata exhibited assimilation rates which were comparable to other C3 species in arid environments. As with Atriplex confertifolia, Ceratoides lanata carried on photosynthesis at relatively low temperatures, but it did not undergo an acclimative shift in the temperature optimum (15 C).
Both species were physiologically adapted to severe moisture stress. They carried out active photosynthesis and respiration at soil water potentials between -15 and -50 bars. As soil water potential decreased below -50 bars, CO2 exchange in Ceratoides lanata was curtailed. Photosynthesis and respiration continued at a moderate level in Atriplex confertifolia until soil water potential was reduced below -70 bars.
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Quantitative Analyses of Perennial Atriplex-Dominated Vegetation of Southeastern UtahSingh, Teja 01 May 1967 (has links)
An Intensive study of the applicability of mathematical methodology to the ordination and classification of desert vegetation was undertaken during 1962, 1963 and 1964. The study area, forming part of the shad-scale zone vegetation and covering 13.5 square miles, is situated near Cisco in Grand County, southeastern Utah. Broad pediments originating from the nearby Book Cliffs are the main landform.
Geologically, the area was subjected to many cycles of erosion. The pediment and the quaternary remnants thin out with increasing distance from the Book Cliffs. The alluvial fan deposits are readily recognizable at three distinct levels. Mancos shale, a lead-gray Cretaceous shale of marine origin, forms the lower part of the Book Cliffs. The alluvial fan deposits are readily recognizable at three distinct levels. Mancos shale, a lead-gray Cretaceous shale of marine origin, forms the lower part of the Book Cliffs and of the pediments originating from it. The vegetation consists of widely-spaced species in which the dominant shrub species belong to the genus Atriplex. The soils have characteristics of Sierozem zonal soils (Aridisols), are often heterogeneous even within short distances and edaphic influences are strong.
In absence of any single over-riding factor, the erosion gradient provided the primary basis for the ordination of vegetation. The gradient is readily noticeable and is accompanied by edaphic and other micro-environmental changes. Four sub-divisions or segments can be easily distinguished. Each segment incorporates a degree of microenvironmental homogeneity and a distinct expression of vegetation in which the transition from the one to the next is usually abrupt. The dominant Atriplex species for each segment, I to IV, are Atriplex confertifolia, A. nuttallii gardneri, and A. Corrugata.
The data on canopy over and frequency were collected for each species. The analyses attempted embraced a wide range of quantitative techniques, namely grouping of species on peak CF (sum of relative canopy cover and relative frequency) value; analysis based on frequency x constancy index; association analysis (among species) using coefficient of interspecific association, chi-square, and their combination; derivation of homogeneous group of vegetation based on presence of single species showing positive association; association analysis and group study based on the use of correlation coefficient; multivariable approaches to the ordination of vegetation employing factor analysis preceded by partition of the sparse data matrix and the Q- and R-techniques of cluster analysis. Prevalent and modal species were also determined for each segment.
The study provided an excellent opportunity to compare and test the validity of results obtained from various analyses and also those that could be easily differentiated from inspection alone. The number and composition of groups derived showed considerable agreement in most cases, though slight variations were introduced inadvertently through subjective, and sometime inevitable, choice of qualitative and quantitative measures employed in particular analyses.
The quantitative approach, with an obvious advantage over the reconnaissance methods, provided a judgement on the significance of similarities and dissimilarities. It also made it possible to detect small differences which were more indicative of pattern, rather than a type, within vegetation area studies. The multivariate techniques of cluster analysis (Q- and R-analyses) illustrated superiority over other methods in that the cluster relations among various entities were readily discernable at all levels of affinity from the hierarchical dendrograms. On the other hand, the techniques utilizing statistical tests of significance necessitate preparing a new dendrogram every time a change is desired in the choice of probability level for testing hypotheses.
The analyses based on prevalent and modal species, and also those using peak values of CF and constancy x frequency indices, provided a quantitative measure of the habitat preference of component species. The quantitative approaches used in the study proved their usefulness and applicability, on the whole, to delimit accurate groups in the shadscale zone vegetation of Southeastern Utah. They also displayed a degree of flexibility, and sophistication, that may be needed in individual studies.
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Effects of Grazing Intensity by Sheep on the Production of Atiplex nummularia and Sheep Live Weight in JordanTadros, Kamal I. 01 May 1987 (has links)
Rangelands in Jordan are deteriorated due to a combination of harsh environmental conditions and human misuse. Jordan is importing increasingly large quantities of meat and animal products to meet the demand from its growing population. Sheep are supplementaQ ly fed during the dry season and large quantities of grain supplements are imported every year.
Significant success has been attained in the establishment of Atriplex nummularia lindl. (ATNU) in Jordan. There is, however, a general lack of adequate research to determine if ATNU is effectively utilized by local sheep, to what extent it is utilized and to what extent it tolerates grazing. The objectives of this research were to determine the effects of grazing ATNU at two intensities (moderate and heavy) on subsequent production of ATNU browse, and on sheep live weight.
Results of this research showed that HNU shrubs are grazing tolerant, they are stimulated by grazing to produce more forage than the non-grazed shrubs. When heavily grazed in the fall, they showed greater compensatory growth than moderately grazed shrubs, but the moderately grazed shrubs gave sustained production better than those heavily grazed in both good and bad years.
Sheep grazing ATNU shrubs with native forage (grasses and forbs) in the fall gained more weight at the moderately grazed treatments. The amount of sheep-live-weight gain was positively affected by the amount of food intake per sheep metabolic body weight and inversely affected by the percentage of ATNU browse in the diet. ATNU although less preferred by sheep than grasses and forbs, could probably be used up to 40% of the diet and still maintain sheep live weight.
ATNU is a good source of forage especially during the dry season, it provides (with native grasses and forbs) a high-quality forage and may considerably reduce the amount of costly supplements imported to Jordan.
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Caracterización y evaluación de los objetivos de forestación de las plantaciones de Atriplex nummularia Lindl. bonificadas mediante D. L. 701 de 1974 en cuatro comunidades agrícolas de la IV Región de CoquimboPeña Gómez, Carolina Anahi January 2006 (has links)
Memoria para optar al Título Profesional de Ingeniero Forestal / Las Comunidades Agrícolas, corresponden a un particular tipo de tenencia de la tierra, donde convive una propiedad común con una individual. Como una alternativa para aumentar la productividad de las praderas, se planteó, en la década de 1970 , la posibilidad de forestar los terrenos degradados por el uso excesivo y destinados al pastoreo del ganado, con especies forrajeras de alto valor nutritivo y palatabilidad para el ganado, aprovechando los beneficios que otorgaba el D.L. 701 de 1974.
Así, a partir de 1975 se desarrolló un proceso de forestación en el secano de la IV Región que ha permitido establecer cerca de 60.000 ha de arbustos forrajeros, estableciéndose más de 10.000 ha en terrenos pertenecientes a las denominadas Comunidades Agrícolas.
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