PLANT ECOLOGY (2)

Author: Luna Trenado María Belén.
Year: 2005.
University: CASTILLA-LA MANCHA [www.uclm.es].
Place of defense: F.Ciencias del Medio A..
Place of preparation: Facultad de Ciencias del Medio Ambiente.

Summary: They are known factors affecting the regeneration of a community plant typically Mediterranean, considering the key determinants of germination capacity of a species representative of that community. It also seeks to simplify the high variability of responses germ found through analysis of different functional groups that allow comparison with other communities with similar characteristics but floristic composition difeferente. The seeds were subjected to different treatments in the lab. First were germinated under four constant temperatures: 10Â ° C, 15Â ° C, 20Â ° C and 25Â ° C. In this experiment simulating the conditions in the absence of fire. In addition, the seeds were subjected to treatment factors associated with direct and indirect fire. In an experiment, the seeds were exposed to different thermal pulses: control 80Â ° C for 10 minutes, 100Â ° C for 10 minutes and 120Â ° C for 10 minutes, simulating the temperatures reached during the passage of a fire. In another experiment, the seeds were put in a factorial treatment of exposure to white light and potassium nitrate 20mM, simulating the conditions in the wake of a fire. Finally, we studied the effect of retardante chemical Fire-Trol 934 highly used in firefighting, at concentrations of 0.02%, 0.2% and 2%. Responses germ of the 58 species studied in this thesis, prior to treatment were analyzed in relation to different functional groups: biotype (caméfitos vs. Hemicriptófitos), regenerative strategy (rebrotadoras vs. Not rebrotadoras), and range of geographical distribution ( endemic species of the Iberian Peninsula, species distribution with Mediterranean species with wider distribution). In general, the species studied showed no specific requirements related to the fire for their germination, although in some cases they could see benefit from them. Therefore, it could be concluded that the regeneration of this community is not linked to the fire. Although the diversity of responses germ is large and depends on many factors, in this thesis highlights the importance of considering functional groups because of their possible differential response

Author: PALACIO BLASCO SARA.
Year: 2005.
University: BARCELONA [www.ub.es].
Place of defense: FACULTAD DE BIOLOGÍA.
Place of preparation: INSTITUTO PIRENAICO DE ECOLOGÍA (CSIC).

Summary: The caméfilos wood dominate large areas of the Mediterranean climate where the low depth of the soil, high levels of stress or frequent disruptions preventing the development of trees and shrubs greater height. However, despite its great importance in the Mediterranean ecosystems, the attention devoted to the study of caméfitos wood has been very limited, especially when compared to the studies carried out on trees and shrubs of the same areas. It is not known, for example, the limits of its ecological diversity. In fact, this type of plants presents a variety of forms of growth appears to be indicative of its various environmental strategies, and therefore, its high functional diversity. However, in most functional classifications made, caméfitos wood mdeiterráneos tend to appear in multiples. The main objective of eta Doctoral Thesis is to deepen the analysis of the environmental strategies of caméfitos wood Mediterranean, by studying the patterns fenomorfológicos and seasonal dynamics of nitrogen (N) and non-structural carbohydrates (CNE) of six species of caméfitos wood Mediterranean representative of the main types fenomorfológicos in this group of plants. To do so, were analyzed monthly for a minimum of 13 months: morphology and activity of the barren, shoot growth, phenology of the aerial part, the growth of raicillas, patterns of living biomass allocation and fotosintétcia, the dynamics of N CNE and the water content in a state of maximum hydration of the branches of the species studied. The analysis of these parameters revealed the existence of certain patones general. All species analyzed and presented buds naked rhythmic patterns of development of their buds and shoots, adjusting these processes to seasonal Mediterranean climate. However, the species studied showed differences in the location of their buds and the extent of its drilling outbreaks, species that submitted their buds braquiblastos (or short branches) emerged outbreaks were partially deformed, while those with greater protection its buds showed outbreaks preformed. The water content in a state of maximum hydration of the branch reached maximum values during the period of extension of outbreaks, which showed a strong relationship between the two processes in species analyzed. The growth of the species raicillas study was limited by the availability of water and the cold winter. There was no meaningful competition between budding and growing raicillas, although those species study with a period of developing their dolicobalstos (or long branches) and tended to separate the two processes over the year. We found various patterns of photosynthetic biomass allocation between species dimorphism with seasonal analyzed. In these species, the formation of leaves tolerant to stress and reduction in the amount of photosynthetic biomass responded with the arrival of the summer drought and reducing winter temperatures. These results show that the seasonal dimorphism is an ecological strategy flexible, since it includes fenologías foliar very contrasting and enables plants to avoid the effects of both drought and cold. The differences in the two species coexisting phenology were translated into dynamic mixed-use and storage of CNE in their bodies wood. However, despite their differences fenomorfológicas, photosynthetic structures served as a source of NyC for spring growth in most evergreen species studied. These results highlight the importance of ecological characteristics morfoló 8 ments (f 795 wine and physiological, facilitating the survival of genetic caméfitos Mediterranean limiting environmental conditions. For example, attributes such as the presence of naked buds with a low level of pre-, The existence of braquiblastos emerged capable of supplying NyCa sprouting, seem to favor the growth of opportunistic type of caméfilos wood Mediterranean areas with arid climates and unpredictable. species without braquiblastos, but with carvings photosynthetic thorny outbreaks and periods highly preformed Short of developing their dolicoblastos seem to be favored in areas with cold winters and dry summers and sometimes subjected to frequent disturbance. In this sense, despite being functionally similar to those braquiblastos in some respects, the stems appear to be photosynthetic an enhanced capacity for tolerance to stress. Consequently, it is suggested that characters such as the type and location of the buds, the presence of braquiblastos or photosynthetic stalks, the degree of seasonal oscillation of biomass or duration of the development of dolicoblastos they are included inthe future functional classifications of this type of plant.

Author: CERMEÑO AINSA PEDRO ALEJANDRO.
Year: 2005.
University: VIGO [www.uvigo.es].
Place of defense: FACULTAD DE CIENCIAS EXPERIMENTALES.
Place of preparation: FACULTAD DE CIENCIAS EXPERIMENTALES.

Summary: The cell size of phytoplankton is a fundamental property of pelagic marine ecosystems. On the one hand the cell size controls key aspects of the biology of these organisms such as metabolic rates, rates of sedimentation or susceptibility to predation. Moreover, the structure size of the phytoplankton community determines the ability of marine ecosystems to recycle organic material or exported to higher trophic levels, adjacent ecosystems, and ultimately, towards the deep ocean where it can be retained for long periods thus controlling levels of CO2 atmosphere and thus contribute to the global control of the peak ground. In essence, but dominated ecosystems planktonic cells phytoplankton small environments are generally very unproductive and they favor recycling processes. The planktonic productive ecosystems, however, are dominated by phytoplankton cells with larger and they favor the process of export. This thesis has analyzed the structure size of the community in terms of phytoplankton abundance and biomass, and photosynthesis during an annual cycle complete in the Ria de Vigo. Our objective was to investigate the role of structure size of phytoplankton in the biogeochemical and ecological functioning of a coastal ecosystem eutrophic. The results obtained in this thesis show that the structure size of the community of phytoplankton in the Ria de Vigo is dominated by large cells during the summer or outcrops, and by a clear codominancia of different size classes during the winter season. During the time of outcrop much of the primary production is exported outside the system, while during the winter period, the bulk of primary production is consumed by the communities heterótrofas of the ecosystem itself. The Ria de Vigo took stock producción-respiración clearly autotrófico throughout the cycle annulled, although the magnitude of the flow is highly dependent on the structure of sizes dela community fitoiplanctón. Our analysis indicates that the patterns of distribution of phytoplankton in coastal system eutrophic as the Ria de Vigo may be related to the high efficiency of phytoplankton photosynthetic large on favorable terms light and nutrients, which, contrary to expectations as the allometric models generally allowed to develop growth rates higher than those achieved by the small size of phytoplankton. In this thesis discusses these results based on the analysis of growth rates and photosynthetic efficiencies in different classes tamñao. Consistent, analysis indicates that certain groups fitopolancton large, mostly diatoms, adaptive advantages such as a high affinity for nutrients, high capacity to attract high-efficiency light or to transfer electrons through fotosistema II. These advantages ecofisiológicas allow these groups of phytoplankton exploit the resources available in the middle and dominate the community. These results are essential for understanding the functioning of ecological communities of phytoplankton and how organic matter is transferred through the different compartments of the coastal marine ecosystems.

Author: OROZCO ABUNDIS MARIO ALBERTO.
Year: 2006.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: ETSEIB.
Place of preparation: EDIFICI TR5 PLANTA 2, DESPATX 2.09 TR.

Summary: The emergence of a new form of agriculture with respect to the environment and linked to the production of healthy food and oriented export market, has been gaining importance in world agriculture over the last three decades. This new way of farming is known as Ecological Agriculture. In this PhD thesis is an analysis of organic farming and products that generated in Europe and particularly in Spain, from the background to the current situation, including benefits, legislation, consumption, quality , certification, strategies identification (tags), among others, as a starting point for the implementation of this sector ecological agriculture Mexican. There will always be a diagnosis from the ecological point of view and shows the opportunity for a country like Mexico, to incorporate this type of agriculture, both to improve the environment and for improved social and economic development, without losing sight of the cultural roots. Mexico is a country with agricultural vocation, with favorable climates and territories available for such holdings, and this thesis demonstrates its viability, through the redemption of traditional technologies and the incorporation of methods of certification and marketing systems, contributing to improving the quality of life of today's society (indigenous, peasants, farmers, traders, consumers, etc..), showing changes in the demand for food, criteria for the new health and environmental requirements. It makes an analysis of the legal framework that mark Mexican law, in terms of regulatory aspects of environmental, ecological balance and soil pollution, explores the social and economic importance, as well as regulations and certification processes, labeling and marketing. As part of priority discusses case studies of organizations already working organic farming in Mexico, and have been recognized on a national level as International, as the case of the Union of Indigenous Communities of the Isthmus Region (UCIRI), the main producers of organic coffee in Mexico, Organic Producers Cape of Baja California Sur and the Sustainable Agriculture Network Alternatives (RASA), based in Guadalajara, Jalisco. examples to follow for the implementation of agriculture that respects the environment to new farming communities in the country, strengthen their cultural identity and the conservation of natural resources. The main product of the Doctoral Thesis, it is generating a proposal for a system of quality assurance in production processes and communication, for the momentum of agroecology in Mexico, a proposal that is geared towards harnessing the power of agroecology as shaft driver of local development, maintaining the workforce in rural areas. ÂQueda lot to build but, as has been shown over the investigation, the potential for local development and aim always optimistic when conjunten the wills and efforts towards a common good ... â

Author: PAZ CANURIA MARÍA ELENA DE.
Year: 2006.
University: LEÓN [www.unileon.es].
Place of defense: FACULTAD DE CIENCIAS BIOLÓGICAS Y AMBIENTALES.
Place of preparation: FACULTAD DE CIENCIAS BIOLÓGIAS Y AMBIENTALES.

Summary: The objectives of this report are focused on the relations between the different series climatófilas vegetation and the respective types of soils on which they operate, as well as to establish the position of serial steps in space and time. First, we applied a methodology consisting of the analytical study prmenorizado of parámtros litológicos, geomorphological, soil and flora and vegetation of the various expressions of landscape plant. This was made profiles and geomorphological schemes were lifted profiles soil corrrespondientes and a catalog flora. Subsequently, through a metolología summarizes were characterized conditions of the natural environment of the series of vegetation in the area, as defined by the metolología fitosociológica from school sigmatista. He then was conducted analysis sinfitosociológico of the landscape. Finally, on the basis of data obtained using statistical techniques and analysis of major components have been identified existing relationships between different sets of vegetation and soil biotypes according to the two most common classifications at present (FAO / STS) and they have created models of correspondence. There were cofeccionado mapping units geoambientales for preparation of soil map with a maximum approximation to the distribution of the series vetación presents in this sector, based on the data obtained and possible extrapolation. Also, in addition to the soil map scale 1:100000, presents a map of the vegetation clomatófila current presence in the territory.

Author: Paris Carolina Ivon.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: Facultad de Biociencias.
Place of preparation: Facultad de Biociencias.

Summary: The invasive ants displace native species of ants and other arthropods. As a result, the interactions of biological system invaded and ecological services performed by the native species are modified. The objective of this work was to investigate the effects of ant invading Lasius neglectus about some of the surface and subsurface components of an oak grove urban and compare them with the effects of native ants, in particular Lasius grandis. Ant invasive Lasius neglectus visit mainly scattered tree where he stayed more months in response to aphids and other insects in the cup of trees. Rather, the visit to the trees by the native ants not depended on the location of the trees. Except in the case of the ant native Lasius grandis, which remained on the trees longer isolated when Lasius neglectus was not present in the fragment. The richness of native species of ants and his visit to the trees was lower in fragmentation of forest where Lasius neglectus was present. Some species of native ants (Crematogaster scutellaris, Temnothorax lichtensteini and Lasius grandis) managed to coexist with invasive. The structure of the community of native ants into fragments with or without Lasius neglectus did not differ from a random pattern. Since the oak tree was more abundant in forest fragments studied were investigated in more detail some effects of the presence of ants on some components of Quercus ilex (oak). Between the months of May and October, we found two species of aphids, Hoplocallis picta, which was occasionally attended, and Lachnus roboris which was the most kind heeded. In oaks visited by the invading ant, it was observed that the abundance of Lachnus roboris tended doubled, as well as its production of molasses, compared with the results obtendios in oaks visited by the ant native Lasius grandis. In addition, the percentage of colonies served by Lasius neglectus was higher than served by Lasius grandis. Consequently, the invasive ant doubled its collection of molasses by oak regarding lahormiga native during the period studied. In oaks visited by Lasius neglectus or Lasius grandis colonies Lachnus roboris were located mainly in the petiole or on the capsid of acorns. However, it was not detected any effect inthe production or quality bellostas in its emergency or quality of the seedlings. Both species of ants captured mainly Pscópteroy Hplocallis picta as a source of protein. The percentage of workers carrying insects or pieces of arthropods between their jaws was superior to Lasius grandis. However, if we consider that the number of workers in Lasius neglectus rise to surpass s oaks in 9 to 1 to the number of workers in Lasius grandis both species quedrían nearly matched in relation to the capture of dams in the cup of oaks. The arthropod community and the level of herbivoría were not modified by the presence of one or another kind of ant. However, some groups showed clear trends. The oaks visited by Lasius neglectus spiders, curculiónidos and aphids tended doubled while larvae coccinellids (predators of aphids) decreased markedly. Typically not all production mix is collected by the ants. Partly remains on the leaves ypuede reach the ground dissolved in water trascolación in the form of dissolved organic carbon (COD). The collection of molasses Lasius neglectus decreased COD content in the water trascolación of oaks which would indicate an interruption of the flow of matter and energy between the cup of oaks and soil nearby. Likewise, the community of microorganisms are differentiated according to the presence of native ants or the invasive; tending the soil microbial biomass to be greater in the case of the presence of Lasius neglectus. According to the town, the quality of litter production was lower in the trees visited by Lasius neglectus. Litter Decomposition of oak was not modified by the presence of invasive ant.

Author: Rey Planellas Sonia.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: Facultad de Biociencias.
Place of preparation: Facultad de Biociencias.

Summary: The study aims to examine: a) the reproductive biology and ecology of the ant invading Lasius neglectus and b) its effects on the native community of arthropods in places invaded NE Spain. This last aspect has been studied in three populations. Likewise, there has been elprimer test control this pest through insecticide contactoy high persistence. The poligínia was demonstrated by studies of reproductive biology. The species shows a densely queens, either isolated or in groups of up to 13 reinas.Por their physiological characteristics of substances reserve, the species is included in the group of ants that can make fundanción independent. For their morphological features (chest proportion queen / worker) is also included in the group of independent foundation. Because of its characteristics for development wing, the species should be able to fly. Despite the earlier findings, swarms have never been seen in any of the known populations around the world. In laboratory showed the possibility of independent foundation and foundation dependent. The most significant impact of the invasion of Lasius neglectus detected in the other ants. The No species coexisting with it is significantly reduced. The effect of the invading other arthropods were variable, depending on the group in question. So aphids were favored positively but spiders, and flies hymenoptera in general, were adversely affected. In control testing insecticides were applied in the tree, in the trunks and inyenctó insecticide on the perimeter of the houses. They also discussed internally with the same baits. The treatment was applied two years in a row. The counting of rows of ants in the trunks and perimeter points with ants showed that the treatments were effective and that the involvement by ants was dropped to acceptable levels by tenants.