EDAPHOLOGY

Author: ABREU XIOMARA DEL CARMEN.
Year: 2004.
University: LLEIDA [www.udl.es].
Place of defense: ETSEA.
Place of preparation: LLEIDA.

Summary: The Priory Geological or Unit Paeozoica Priorato, is one of the areas most famous wine of Spain and recognized intemacionalmente because of the high quality of its wines. The main characteristic of the soils, called 'licorellas', is taking place on blackboards or paleozoics shale, which printed a character peculiar to the area, high quality wines and their particular interest by investors. In this regard have been replanted and planted new vineyards, which sometimes involve large movements of land for the construction of terraces. These changes could significantly alter the equilibrío agroecológico in this region, especially at the low awareness of the limitations and potential of these lands. It is now common to find plots with terraces, which showed degradation problems such as grooves, mass movements and gullies. Some producers have adopted the technique of mechanical grinding of the coarse fraction of the soil surface to create terraces of a much smaller size to that found in natural conditions. In doing so, and with large cuts and earth movements, can produce significant changes in the hydrologic behavior of these soils. In that sense, this research is intended to contribute to knowledge of the hydrological properties and susceptibility to erosion and surface mass of some stony soil of this region. It raised the following objectives: i) to assess the effect of different fractions of soil, level of coverage stones and outstanding in the production of sediments in stony soil under simulated rainfall, ii) to identify and compare the characteristics físico-hidrológicas, chemical and mineralogical some soils, m) to evaluate the effect of aterrazamiento on the hydrological properties and the production of water and sediment and iv) to estimate the risk of erosion by mass movements in stony soil, through determinations field laboratory , and process modeling. To find the behavior of these soils were conducted studies of the mechanical properties and hydrological, and the assessment of hydrological processes in the field and laboratory. Finally, the information generated will be integrated into a hydrologic model, which allowed simulate potential risk periods of mass movements. The results indicate the high pedregosídad of these soils, characterized by frank sandy texture to areno frank (fraction less than 2 mm), very low content of clay (smectite), low plasticity. They also offer a low moisture retention capacity and very high infiltration. Therefore, even in steep slopes, all the water that falls can infiltrate, which somehow makes it susceptible to that limit reached liquid, these soils can slip by mass movements. The risks are greatest mass movements during díciembre-enero. While these periods of risks may arise, it's duration was reduced to only short periods of time, as the water drains very quickly towards deeper layers. Only submit two or more consecutive days of risk, if they occur rains followed by large-scale, where soil moisture is very close to field capacity. While in the area of slope can be found little deep soils, water drains quickly towards deeper layers due to the nature of exfoliating tabloids and the presence of cracks and fractures. It concludes that many of the traditional methodologies for assessing properties hydrological and susceptibility to water erosion and surface mass, are not suitable for studying the behavior of stony soil, espe-cial, those related to infiltration and water erosion. Moreover, the simulation field and laboratory scale movements, together with the application of hydrological models can enable predict behavior 8 of this 31d s special events soil before rain and thus set the stage for use and manejomás appropriate to prevent the degradation of these soils.

Author: HERNÁNDEZ GARCÍA DIANA.
Year: 2005.
University: AUTÓNOMA DE MADRID [www.uam.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: This Doctoral Thesis deals with the study of agronomic use of pig slurry, in order to provide an adequate solution to the growing production of this residue, improve soil fertility farm in a way that respects the environment. To do so, were studied in the field and cumulative residual effects of the application of pig slurry at various doses on fertility and physicochemical properties, biological and biochemical a degraded soil representative of a semiarid agroecosystem, valuing especially transformations organic matter and the risks of contamination in soil and plants. The experimental design consisted of plots planted with barley and amended with 30, 60, 90, 120 and 150 m3 ha-1 of pig slurry, which were compared with a ground control and with a fertilization treatment ore annually. A block of plots received a single addition of slurry at the start of the experiment in 1997 in order to study the residual effect in subsequent years, while the other set was amended for seven consecutive years to study the cumulative effect of the application of slurry . This paper includes the results of the last three years. Overall, the annual slurry fertilization improves the response of the crop, increasing the production values regarding fertilization ore, without being aware of problems or heavy metal contamination in grain and straw. The study of fertilizer efficiency indices reveals that the use of moderate doses achieved more efficient use of N applied. The soils amended with slurry experiencing an increase in pH, electrical conductivity and the content of nitrates, P, Ca and Na equivalent. The total concentration of Cu equivalent and potentially increases the ground control after seven years of implementation, but do not reach levels considered pollutants. The contents of total organic C and analyzed the organic fractions (húmicas substances and water-soluble compounds) barely affected by the application of slurry, but show a gradual decline in all treatments over time, which shows the limited capacity of the amendment to mitigate the degradation of soil organic matter caused by environmental conditions and agricultural management. In fact, the study of the isotopic concentration of 13C indicates a significant incorporation of C from the slurry and suggests a mineralization of organic matter native. It has also marked the humic acids and fúlvicos of pig slurry, ground control and the amended with 90 and 150 m3 ha-1 for seven years. The addition of pig slurry influence on the composition, molecular structure, behavior acid and the ability to form complexes with Cu (II) and Zn (II) húmicas substances from soils amended, which suggests partially transposed húmica fraction of the slurry in the native soil. The input of organic matter readily biodegradable induces a revival of growth and soil biological activity, as reveal the contents of microbial biomass C and activities oxidorreductasas. The results of the metabolic ratio point towards an easing of the situation of stress for biological populations, but this effect is temporary due to resource depletion bioavailable, as indicated by the fact that the baseline barely breathing is affected. The addition of slurry provokes responses in various activities hidrolasas; phosphatase activity is inhibited annually as a result of a high availability of 8 P mien 303 after that urease hardly varies and activities proteasa-BAA and Ã-glucosidasa stimulate in response to the incorporation of organic substrates.

Author: Ortega Pérez Raúl.
Year: 2005.
University: ALMERÍA [www.ual.es].
Place of defense: D.Edafología y Química Agrícola.
Place of preparation: Universidad de Almería.

Author: SALES DÁVILA BEATRIZ.
Year: 2005.
University: SEVILLA [www.us.es].
Place of defense: INSTITUTO DE RECURSOS NATURALES Y AGROBIOLOGÍA DE SEVILLA.
Place of preparation: UNIVERSIDAD DE SEVILLA.

Summary: Integrated Survey of different fractions of organic matter (OM) in soils representative of Peru's Amazonian ecosystems, specifically the Department of Ucayali (Pucallpa area), under different systems of use and management, the objective is to assess the importance of these ecosystems in storage C in tropical systems. They apply appropriate techniques for the study of complex matrices, how destructive type of analytical pyrolysis (Py-GC/MS) and sequential chemical degradation and espectrográficas how FT-IR and 13C NMR in solid form. The first approach involves valid knowledge of the current status (physicochemical characteristics and quality of MO) Soil Ecosystem representative of Amazonian Peru. Research that will be the basis for INIA-Perú perform the following two actions: A Monitor-time changes in the frequent changes made by management and land use in their properties. B-Predicting residence times (turnover) of the forms of C, and thus support the design of management policies aimed at enhancing the capacity of storage and sequestration of C in organic soils.