Abstract:The Andes of northern Peru are still widely covered with forests, but increasingly suffer from habitat fragmentation. Subsequent soil degradation often leads to the abandonment of overused forests and pastures. Ecological knowledge on the restoration potential, e.g., on dependencies of soil conditions and altitude, is scarce. Therefore, we compared soil and vegetation patterns along nine transects within the upper Pomacochas Basin, which is an important biodiversity corridor along the Andes, between remaining forests, succession sites and pastures. Anthropogenic successional and disturbance levels, geological substrate, and altitude have the most important ecological impacts on vegetation and tree species composition. Species responded to sandstone versus calcareous substrates, but also to depths of the organic soil layer, and light conditions. The absence of organic layers under pastures contrasted with the accumulation of thick organic layers under forest cover. Vegetation composition at succession sites revealed certain starting points (herbal stage, bush stage, or secondary forest) for restoration that will determine the length of regeneration paths. Pre-forest patches of Alchornea sp. and Parathesis sp. may act as habitat stepping stones for expeditiously restoring biocorridors for wildlife. The key findings can contribute to the sustainable use and conservation of biodiversity in a fragile ecoregion.

SUMMARYIn the western region of Patagonia, Argentina, there are about 70 thousand ha of afforestations, with 80% corresponding to Pinus ponderosa and the rest to Douglas fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta). To avoid the tendency to this kind of monocultures, with their unfavorable ecological and sanitary consequences, there is a need of evaluating the possibility of cultivating other timber species, to allow for the diversification of the current afforestations. In this study, small stands and groups of trees planted in the last 50 years were sampled, identifying the species present and measuring height, age and diameter of trees, as well as recording the environmental conditions where they grow. Those healthy species, that were found in two or more sites, and whose growth parameters resulted higher than those found in their places of origin, were selected as promissory species. Measured dominant heights were compared with those appearing in yield tables and site index curves for their natural distribution areas, so as to evaluate their growth potential. The species that showed higher heights than the same species grown in their native areas, were healthier, had high wood quality and a recognised value in the wood market were: Quercus robur, Pinus monticola, Pinus sylvestris and Larix decidua. All demonstrated a high potential to make provenances and plantation trials to diversify afforestations in Patagonia.Key words: forest species introduction, site index, Patagonia. RESUMENEn el oeste de la Patagonia argentina existen aproximadamente 70 mil hectáreas forestadas, de las cuales el 80% corresponde a Pinus ponderosa y el resto a Pseudotsuga menziesii y Pinus contorta. Con el objetivo de evitar esta tendencia hacia los monocultivos con sus consecuencias ecológicas y sanitarias desfavorables, surge la necesidad de evaluar la posibilidad de cultivar otras especies forestales que permitan la diversificación de las actuales forestaciones. En este trabajo se analizaron pequeños rodales y grupos de árboles plantados en los últimos 50 años en la región, identificando las especies presentes y midiendo en ellas las variables dasométricas, de sanidad y forma, así como las condiciones ambientales en las que crecieron. Aquellas especies sanas, que se presentaron en dos o más sitios y cuyos parámetros de crecimiento resultaron superiores a los lugares de origen, fueron elegidas como promisorias. Para evaluar su potencial de crecimiento se compararon las alturas dominantes observadas con las de tablas de producción a la misma edad e índice de sitio de esas especies en su área de distribución natural. Las especies que presentaron mayor crecimiento que en su lugar de origen, tienen maderas de calidad, reconocido valor en el mercado y resultaron promisorias fueron: Quercus robur, Pinus monticola, Pinus sylvestris y Larix decidua. Éstas demostraron un gran potencial de cultivo y se proponen para ensayos de procedencia y plantación para diversificar forestaciones.Palabras clave: introducción de especies,...

Concerted efforts are required to achieve the UN Sustainable Development Goals (SDGs) of the 2030 Agenda. In our study, we intend to outline how valuable synergy effects can be obtained from bilateral cooperation between Germany and Patagonia in order to protect temperate forest ecosystems and to ensure long-term and sustainable use of terrestrial natural resources. The additional benefit of this transcontinental and transhemispherical cooperation is that there are analogies between the Northern and Southern hemispheres, but also distinct differences that complement each other perfectly. We show in an exemplary way, how the challenges of Global Warming and the associated increased vulnerability to forest fires and other natural risks can be tackled. Knowledge transfer and common strategies will provide sound solutions for SDG 13 (urgent action to combat climate change and its impacts), SDG 15 (sustainable use of terrestrial ecosystems, sustainably managed forests, combating desertification, and halting and reversing land degradation and halting biodiversity loss) and SDG 17 (strengthening the means of implementation and revitalizing the global partnership for sustainable development). scientific research and a global political challenge to tackle this

Lomatia hirsuta (Lam.) Diels is a pioneer tree species that develops after wildfires, and in advanced successional stages, it is often found as a secondary species in Patagonian forests. However, in El Manso Valley, Province of Río Negro in Western Argentina, L. hirsuta forms mature pure stands, originated from stump shoots. The wood is very attractive for its colourful appearance and beautiful grain. Nevertheless, these forests are not managed for timber production, they are mostly strong thinned for grazing, and the wood is mainly used as firewood. The objective of this study was to evaluate the possibility to improve quality wood production in stands through silvicultural interventions in a sustainable way. Samples have been carried out in stands of different developmental stages. We evaluated the state and quality of the trees, and their growth has been studied by means of trunk analysis. The results indicate that there is significant potential to improve the production of quality wood in dense stands by thinning to release crop trees. Thinning should start in young stands. It also became apparent that forest management is first necessary to stabilise these nearly unattended forests.

Lomatia hirsuta (Lam.) Diels is a pioneer tree species that regenerates mostly after fire, and more frequently found as a secondary species in Patagonian forests dominated by Austrocedrus chilensis and Nothofagus dombeyi. However, in the El Manso Valley, Province of Río Negro in Western Argentina, L. hirsuta forms pure stands, originated from stump shoots. The wood is very attractive for its colourful appearance and beautiful grain, suitable for fine furniture. Nevertheless, these forests are not managed for timber production, they are mostly thinned for grazing, and the wood is mainly used as firewood. The objective of this study was to evaluate the possibility to improve quality wood production in stands through silvicultural interventions in a sustainable way. Samples have been carried out in dense stands of different ages and in one less dense stand with the traditional use for pastures. We evaluated the state and quality of the trees, and their growth has been studied by means of trunk analysis. The results indicate, that there is a significant potential to improve the production of quality wood in dense stands through thinning oriented to crop trees. This should start in young stands, because in older stands, good form and sound trees are already considerably reduced. It also became apparent, that forest management is necessary to stabilize these nearly unattended forests, which in old stands are very vulnerable to damages caused by wind and wet snow. In such stands the extraction of trees could be combined with the planting of seed trees, with the expectation to improve the quality and vigour of the trees at maturity.