Equações de afilamento e volume para tamanhos comerciais de nothofagus obliqua e N. alpina

Timber volume of standing trees is essential information for managementdecisions. The increasing need to optimize the potential capacity of forests maintaining their conservation, requires the quantification of the different potential possible timber products. The aim was to adjust taper equations to determine volumes of different timber products for commercial stems of Nothofagus alpina and N. obliqua. Trees of both species were randomly selected in harvesting areas of Lanin National Park (Argentina).Trees were felled and cut into commercial logs, measuring diameter with bark at different heights up to the beginning of the crown, and for each tree the diameter at breast height and total height. Five taper equations were selected and non-linear regression processes were employed for the fittings. We obtained the volume through the integration of the stem profile equation and the rotation in the space thereof through solid of revolution.The Bennet and Swindel (1972) model was selected for both Nothofagus species,obtaining similar equation parameters and differences were observed at the top of the stems of larger trees. For this the use of an integrated model is not recommended. With the obtained equations it is possible to: (i) estimate volume at different heights and for different commercial diameters, and (ii) predict the height at which both species reach to a certain diameter. The model presented some statistical limitations (e.g. multicollinearity), however, the fitting of the equation and the easy understanding of the outputs support itas a useful tool in a broad range of forest applications.O volume de madeira das árvores em pé é uma informação essencial para as decisões de gestão. A crescente necessidade de otimizar a capacidade potencial das florestas mantendo sua conservação, requer a quantificação dos diferentes possíveis produtos de madeira possíveis. O objetivo era ajustar equações de afilamento para determinar volumes de diferentes produtos de madeira para hastes comerciais de Nothofagus alpina e N. obliqua. As árvores de ambas as espécies foram selecionadas ao acaso nas áreas de colheita do Parque Nacional Lanin (Argentina). As árvores foram derrubadas e cortadas em troncos comerciais, medindo o diâmetro com a casca em diferentes alturas até o início da coroa, e para cada árvore o diâmetro na altura do peito e altura total. Foram selecionadas cinco equações cônicas e foram empregados processos de regressão não-linear para ajustar. Obtivemos o volume através da integração da equação do perfil do caule e da rotação no seu espaço através do sólido da revolução. O modelo de Bennet e Swindel (1972) foi selecionado para as duas espécies de Nothofagus, obtendo parâmetros de equação semelhantes e observando-se diferenças no topo das hastes de árvores maiores. Portanto, o uso de um modelo integrado não é recomendado. Com as equações obtidas é possível: (i) estimar o volume em diferentes alturas e para diferentes diâmetros comerciais, e (ii) prever a altura em que ambas as espécies atingem um determinado diâmetro. O modelo apresentou algumas limitações estatísticas (por exemplo, multicolinearidade), no entanto, o ajuste da equação e a compreensão fácil das saídas o suportam como uma ferramenta útil em uma ampla gama de aplicações florestais.Fil: Attis Beltran, Hernan. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chauchard, Luis. Universidad Nacional del Comahue; ArgentinaFil: Iaconis, Ariana. University of Sydney; AustraliaFil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin

Un nid de guêpes

Paris, qui a largement inspiré le roman noir, lui devait bien une messe (noire). Son église est une bibliothèque : la Bilipo. Le catéchisme de la bibliothéconomie s’est adapté à la loi du milieu et, chaque année, le concile y rédige une nouvelle bible en noir et jaune, Les crimes de l’année. Un vrai nid de guêpes

Crecimiento y producción de repoblaciones de Pinus radiata D. Don en la provincia de Guipúzcoa (País Vasco)

Esta tesis tiene la finalidad de desarrollar las bases de un modelo para la predicción del crecimiento y la producción de las masa de Pinus radiata D.don en la provincia de Guipúzcoa, (País Vasco). Los modelos se componen de funciones de transición que respetan ciertos principios biológicos y propiedades matemáticas. Además cada función fue verificada y validada, esto último cuando se contó con la muestra independiente apropiada, con ello se obtuvieron los correspondientes errores de estimación y la exactitud del modelo. El estudio consta de tres capítulos principales, el estudio de la calidad de estación, el desarrollo de las funciones de crecimiento del rodal y por último una aplicación práctica de los resultados obtenidos. La calidad de estación se estudió a través del crecimiento en altura dominante del rodal, empleando además la metodología del índice de estación o sitio. En primer lugar, se caracterizaron los patrones de crecimiento en la altura dominante en relación a la calidad de estación. De ello resultó que en las diferentes calidades de estación, los rodales de Pinus radiata mostraron culminaciones del incremento corriente anual muy tempranas para luego mantener un crecimiento sensiblemente proporcionales entre las diferentes estaciones. Se desarrolló un método independiente para la clasificación de la estación. El método se denomina del Intercepto de Crecimiento o de Intercepción y consiste en relacionar la altura dominante del rodal con el índice de estación a través de una función lineal simple. Esto se puede considerar inédito en el país y resuelve un problema planteado por los forestales del País Vasco. Finalmente se construyeron dos sistemas de curvas altura dominante-edad. que se confrontaron contra los sistemas desarrollados anteriormente. Las funciones de crecimiento del rodal se estudiaron con la variable área basal o basimétrica como variable de respuesta. Se desarrollaron diferentes métodos de predicción. Uno emplea el vínculo o relación entre dos índice de densidad, la Densidad Relativa de Curtis (1982) y el Factor de Altura de Andenmatten et al.(1997). El otro consiste en dos ecuaciones diferenciales de crecimiento que se diferencian entre sí en la variable conductora asociada con el tiempo que emplean. Mientras una usa la variable edad, al estilo tradicional, la otra se basa en la teoría del espacio de los estados y emplea la variable de estado altura dominante. La aplicación práctica consiste en unas nuevas tablas de producción para la especie. Se propone un cambio innovador en el funcionamiento de una tabla. Se podría considerar que se han logrado una mejora en las típicas tablas de selvicultura variable (tercera generación) y de selvicultura a la carta (cuarta generación). Las mismas deben considerarse como provisionales dado que las funciones de volumen que incluyen son preliminares pues su perfeccionamiento escapan a los objetivos de la tesis. SUMMARY Since recent years there is the need to improve the stand growth and yield prediction techniques. This gave rise to implement simulators that liberalize silvicultural decisions, instead of using traditional and rigid yield tables. The purpose of this thesis is to develop growth and yield models for Pinus radiáis D. Don in Guipúzcoa, Basque-Country, Spain. These models include important biological and mathematical principies. Each function was verified and validated, when the independent sample was a proper one, and it allowed to obtain an estimation error and model accuracy. This research has three main chapters: study of site quality, develop of growth functions and practica! applications of the results. Site quality was studied through both top height growth and site index methodology. Firstly the top height patterns in relation to site index were studied. The patterns showed early height annual increment and a later proportional growth, between different site qualities. To estímate site index the growth intercept method was adapted for polyciclic species as Pinus radiata. This method allowed to estímate site index in young stands (5-10 years oíd). Finally two set of site quality curves were developed and they were compared with the previously developed systems. Through this comparison, the extend of errors could be defined when inadequated curves were applied. Differences over 15 percent in top height estimations among different systems were found. The basal área was the predictable variable used in the stand's growth model. Two different prediction methods were developed. One of them uses the link or relation between two stands density indexes (STDI), Curti's Relative Density (1982) and the Height Factor (Andenmatten et al., 1997). The other one lies in two differential growth equations, which differ in the driver variable associated with the time. While one in the traditional way, uses age as a variable, the other one uses top height as a variable of state (based on the theory of states' space). The models were verified with permanent sample plots' data. The output of the models were compared with the real basal área evolutions. All of them were quité precise, with errors arround 6 and 8 percent. The practical application consisted in the construction of new yield tables for this species. An inovative change in the functioning of the tables was proposed. I consider that an improvement of the typical variable silvicultural table (3*^ generation) and in the particular silviculture table (4* generation) has been achieved. These tables should be considered as provisional ones, because they include preliminary volume functions. The improvement of these functions are beyond the objectives of this thesis

GeoTraceAgri final project report (GTA)

Are the universalisation and the globalisation of trade exchanges synonymous with a standardization in which agro-food products uprooted of their soil will no longer be differentiated from manufacturers or supermarket brands? Original food products belong to the inheritance of the territories and the consumers are attracted more and more by their authenticity. The GeoTraceAgri project resolutely supports agriculture and the sustainable promotion of the territory as opposed to universalisation which standardizes and moves away those who produce for consumers. Geotraceability aims at associating information of geographical nature with the traditional data of traceability. Farming origin and operations have become factual and verifi able data is available everywhere in the world, thus making it possible to bring additional guarantees to the signs of quality. The GeoTraceAgri (GTA) project largely contributed to the realisation of geotraceability. With the implementation from January 1,2005 of the new Common Agricultural Policy and its regulation imposing on the Member States a single system of declaration, all the agricultural parcels now form part of a European database of geographical references. This new regulation reinforces the basis of the concept of geotraceability, whereas throughout the project it was necessary to defi ne geo-indicators for integrated or crop production with very few geographical data on the farming precedents. The development of the GTA prototype rests on a decentralized architecture and Web services. It was indeed necessary to conceive a system which is readily accessible on Internet for farmers, co-operatives and collectors, and potentially with the administrations which have control responsibilities. In term of acceptability, the potential users realise the potential economic benefi ts of the concept and of the indicators of geotraceability in their plan of exploitation, on the other hand sociological acceptability is less evident which induces the need for communication to make for its adoption. This fi nal report fi nal illustrates the fi rst stage : the GeoTraceAgri partners are continuing their research on the defi nition of an integrated system of geotraceability for the Common agricultural policy and the plan of analysis of the results of GeoTraceAgri should lead to the marketing within two years of an application making it possible to integrate the geo-indicators into management software for the actors of the agro food chain

Stand development stages and recruitment patterns influence fine-scale spatial genetic structure in two Patagonian Nothofagus species

Key message: Nothofagus alpina (Poepp. et Endl.) Oerst. and Nothofagus obliqua (Mirb.) Oerst forests have strong fine-scale spatial genetic structures. The intensity of genetic structure patterns differed according to species, stand development stages, life stages, and spatial arrangement of regeneration groups. This data becomes useful for forest management as it provides an understanding of how populations evolve as well as of the consequences of disturbances and enables the establishment of sampling strategies. Context: The understanding of fine-scale spatial genetic structure in natural populations is useful for forest management. Although Nothofagus alpina (Poepp. et Endl.) Oerst. and N. obliqua (Mirb.) are important species of the Patagonian forest, little is known about the genetic structure of their populations. Aims: The main objectives were to investigate the differences in fine-scale spatial genetic structure among mature tree populations of both species considering two stands at different development stages. Genetic structure was also evaluated among life stages and spatial distribution groups of regeneration within the old-growth stand. Methods: Genetic structure was examined by microsatellite DNA analysis of regeneration and mature tree populations of both species (around 1300 individuals). Gene dispersal distance was additionally estimated. Results: In both stands and species, strong fine-scale spatial genetic structure and short dispersal distance were found. This pattern was stronger in the early successional forest, in N. obliqua populations, in earlier life stages, and in scattered regeneration. Conclusion: Stand development stages and recruitment patterns influence the fine-scale spatial genetic structure of both Nothofagus species. However, the genetic structure also differs between species.Estación Experimental Agropecuaria BarilocheFil: Sola, Georgina. Universidad Nacional del Comahue; ArgentinaFil: Sola, Georgina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; ArgentinaFil: Marchelli, Paula. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Grupo de Ecologia Forestal; ArgentinaFil: Marchelli, Paula. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnologia Agropecuaria (INTA). Estacion Experimental Agropecuaria Bariloche. Area Forestal; ArgentinaFil: Chauchard, Luis. Universidad Nacional del Comahue; ArgentinaFil: El Mujtar, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: El Mujtar, Veronica Andrea. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentin

Mixed Nothofagus forest management: a crucial link between regeneration, site and microsite conditions

Canopy openings due to harvesting practices constitute a disturbance that changes the environmental conditions of microsites. Its impact on the relative performance of the regeneration of different tree species could also be affected by site conditions and forest structure.The objective of this study was to determine how regeneration establishment of Nothofagus mixed forests is influenced by shelterwood silvicultural system. We focused on Lanín National Reserve (Neuquén, Argentina) where this silvicultural system has been applied since the late 1980s. The microsite scale analysis (one managed forest) showed that canopy cover was a key factor conditioning Nothofagus regeneration establishment, with older and larger individuals growing in less exposed microsites. Low understory dominance and leaf litter thickness were also associated with microsites with regeneration, while successful establishment (saplings taller than 2 m) showed positive correlation with soil moisture. Variations of these patterns were observed among species reflecting their specific ecophysiological requirements. On a stand scale (two managed forests along Lacar watershed) regeneration of N. dombeyi and N. alpina showed significant correlation with site and specific basal area, while N. obliqua was correlated with total basal area. Regeneration taller than 2 m was mainly correlated with site and altitude. At both, microsite and stand scale, the relative abundance of species changed between mature trees and regeneration. In particular, for N. alpina, an abundance decrease was observed on regeneration. Our results suggest that forest management systems should diversify silvicultural practices throughout the forest landscape, to provide at each site the micro-environmental conditions required by each species in order to maintain biodiversity and forest functions.Estación Experimental Agropecuaria BarilocheFil: Sola, Georgina Giselle. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. CCT-Patagonia Norte; ArgentinaFil: El Mujtar, Veronica Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área Sistemas Forestales. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Attis Beltran, Hernan. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; ArgentinaFil: Chauchard, Luis Mario. Universidad Nacional del Comahue. Cátedra de Ordenación Forestal; ArgentinaFil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área Sistemas Forestales. Unidad de Genética Ecológica y Mejoramiento Forestal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin