• Energy Research

1 IntroducciónDada la apremiante necesidad de cuantificar los flujos de carbono asociados con la dinámica de la vegetación terrestre, un número creciente de investigadores ha tratado de mejorar las estimaciones del volumen de árboles,la biomasa y las reservas de carbono. Las ecuaciones alométricas de árboles son herramientas críticas para tal propósito y tienen el potencial de mejorar nuestra comprensión sobre el secuestro de carbono en la vegetación boscosa, para apoyar la implementación de políticas y mecanismos diseñados para mitigar el cambio climático (por ejemplo, CDM y REDD+; Agrawal et al. 2011), para calcular los costos y beneficios asociados con los proyectos de carbono forestal, y para mejorar los sistemas de bioenergía y la gestión forestal sostenible (Henry et al. 2013). 1 Introduction Étant donné le besoin urgent de quantifier les flux de carbone associés à la dynamique de la végétation terrestre, un nombre croissant de chercheurs ont cherché à améliorer les estimations du volume des arbres, de la biomasse et des stocks de carbone. Les équations allométriques des arbres sont des outils essentiels à cette fin et ont le potentiel d'améliorer notre compréhension de la séquestration du carbone dans la végétation ligneuse, de soutenir la mise en œuvre de politiques et de mécanismes conçus pour atténuer le changement climatique (par exemple, CDM et REDD+ ; Agrawal et al. 2011), de calculer les coûts et les avantages associés aux projets de carbone forestier, et d'améliorer les systèmes de bioénergie et la gestion durable des forêts (Henry et al. 2013). 1 IntroductionGiven the pressing need to quantify carbon fluxes associatedwith terrestrial vegetation dynamics, an increasing number ofresearchers have sought to improve estimates of tree volume,biomass, and carbon stocks. Tree allometric equations arecritical tools for such purpose and have the potential toimprove our understanding about carbon sequestration inwoody vegetation, to support the implementation of policiesand mechanisms designed to mitigate climate change (e.g.CDM and REDD+; Agrawal et al. 2011), to calculate costsand benefits associated with forest carbon projects, and toimprove bioenergy systems and sustainable forest manage-ment (Henry et al. 2013). 1 المقدمة بالنظر إلى الحاجة الملحة لقياس تدفقات الكربون المرتبطة بديناميكيات الغطاء النباتي الأرضي، سعى عدد متزايد من الباحثين إلى تحسين تقديرات حجم الأشجار والكتلة الحيوية ومخزونات الكربون. تعد المعادلات المتجانسة للأشجار أدوات حاسمة لهذا الغرض ولديها القدرة على تحسين فهمنا لعزل الكربون في الغطاء النباتي الخشبي، لدعم تنفيذ السياسات والآليات المصممة للتخفيف من تغير المناخ (مثل CDM و REDD+؛ Agrawal et al. 2011)، لحساب التكاليف والفوائد المرتبطة بمشاريع كربون الغابات، وتحسين أنظمة الطاقة الحيوية والإدارة المستدامة للغابات (Henry et al. 2013).

<p><strong>Abstract: Tree above-ground biomass allometries for carbon stocks estimation in the Caribbean mangroves in Colombia</strong></p><p>In this study, we analyzed the above ground biomass of the species <em>Rhizophora mangle</em> and <em>Avicennia germinans</em> in the mangrove ecosystem located at Marine Protected Area called in Spanish Distrito de Manejo Integrado (DMI) Cispatá-Tinajones-La Balsa, Caribbean Colombian coast. We harvest 30 individuals of each species in field and built allometric models in order to estimates of aboveground biomass with low levels of uncertainty. Our results indicate that the above ground biomass of mangrove forests in the DMI Colombian Caribbean is the 129.69±20.24Mg/ha, the equivalent to 64.85±10.12MgC/ha. The DMI has an area of 8 570.9ha in mangrove forests, and we estimated the total carbon potential stored is about 555 795.93Mg. Although there are pantropical and national above ground biomass allometric models, most of them do not discriminate mangrove forests, despite being particular ecosystems. The equations generated in this study can be considered as an alternative for the assessment of carbon stocks in above ground biomass of mangrove forests in Colombia, and can be used for analysis at a more detailed scale and they are useful for determinate the potential for carbon storage in mangrove forests like an option for the country in forest conservation and emission reduction by deforestation.</p>

Abstract Temperature is a crucial factor influencing the growth of forest plantations, and a key variable used in process-based models of forest productivity. In the present study, we evaluated the relationship between temperature and growth of seven Eucalyptus genotypes in eight sites across a 3500 km latitude gradient in South America. From 18 months after planting until 72 months of age, climatic data and tree diameter increments at breast height (1.3 m above ground level) were monitored in each site intensively (every 15-30 days). The optimum temperature to growth varied among genotypes, ranging from 18 to 22 °C. The minimum annual temperature required for growth was 6 °C, while the maximum was 31 °C. The results at a monthly scale indicate that the minimum temperature to growth is between 7 °C and 23 °C, while the monthly maximum temperature is between 15 °C and 31 °C. When we used annual temperature or large temporal scales, we potentially minimize the effects of climate on plant metabolism; this should be taken into account in process based-models. The study results enhance our understanding of the influence of air temperature on tree growth dynamics. The Eucalyptus genotypes most planted in Brazil and Uruguay have specific thermal demands for growth maintenance and different optimal temperatures for maximum growth. Understanding variation in growth under different climatic conditions would facilitate accurate prediction of forest productivity based on thermal requirements. In addition, the data presented here could facilitate tree breeding by enhancing phenotypic analyses based on ecophysiological factors during the selection process.