LISEA

The objective of this work was to develop equations of thickness profile and bark volume at different heights with easy-measurement variables, taking as a study case Nothofagus pumilio forests, growing in different site qualities and growth phases in Southern Patagonia. Data was collected from 717 harvested trees. Three models were fitted using multiple, non-lineal regression and generalized linear model, by stepwise methodology, iteratively reweighted least squares method for maximum likelihood estimation and Marquardt algorithm. The dependent variables were diameter at 1.30 m height (DBH), relative height (RH) and growth phase (GP). The statistic evaluation was made through the adjusted determinant coefficient (r 2 -adj), standard error of the estimation (SEE), mean absolute error and residual analysis. All models presented good fitness with a significant correlation with the growth phase. A decrease in the thickness was observed when the relative height increase. Moreover, a bark coefficient was made to calculate volume with and without bark of individual trees, where significant differences according to site quality of the stands and DBH class of the trees were observed. It can be concluded that the prediction of bark thickness and bark coefficient is possible using DBH, height, site quality and growth phase, common and easymeasurement variables used in forest inventories.

El género Nothofagus comprende alrededor de 35 especies nativas del Hemisferio Sur. En la Patagonia se han citado numerosos ejemplos de híbridos naturales entre varias especies de Nothofagus. El objetivo del presente trabajo fue analizar y describir la evidencia de la existencia de posibles híbridos naturales entre Nothofagus pumilio y N. antarctica en Patagonia Sur, mediante el estudio de caracteres morfológicos foliares. Se trabajó con 20 posibles híbridos recolectados en una zona de transición entre bosques de N. pumilio y N. antarctica de Tierra del Fuego, y con individuos de N. pumilio y N. antarctica obtenidos de poblaciones puras cercanas a las anteriores. Por medio de un muestreo aleatorio se seleccionaron 20 hojas de cada individuo a las que se les midió largo, ancho, distancia del mayor ancho a la base, forma, base, borde, ápice y largo del pecíolo. Las hojas de los posibles híbridos difirieron de N. pumilio en tamaño, distancia del ancho máximo a la base y frecuencia de a...

Private institutions for third-party (eco-)labelling of food and wood products has been a lively field of empirical research, peaking in the conception of certification as a ''non-state market-driven governance system,'' which is gaining rule-making authority domestically and internationally as a private governance institution and a transnational regime. Recent findings, however, suggest that state actors also play a decisive role in private certification governance. Questions relating to who within the state, however, so far remain unaddressed. Very recent empirical trends in the fields of timber and palm oil certification in Indonesia suggest that it is distinct public bureaucracies who start reclaiming certification authority through state-led mandatory schemes, challenging the private and transnational certification institutions in support of government-driven international certification regimes. Against this background, the objective of this paper is to substantiate the trend from transnational private to international state-driven governance by analyzing the role of distinct state bureaucracies in the emergence, diffusion, and reshaping of private natural resource governance systems. To achieve these objectives, we develop our propositions by combining insights from political certification studies, regime theory, as well as bureaucratic politics theory. Methodologically, we employ a qualitative case study design on recent developments in forest, timber, and palm oil certification systems in Argentina and Indonesia. Our results substantiate the observation that distinct state actors play a key role in private governance systems and, in the case of Indonesia, even reclaim labelling authority from private institutions by attempting to outcompete them through employing their exclusive regulatory power. The results further indicate a strong, self-interested support from domestic state bureaucracies to state-driven international rather than to transnational certification regimes, supporting the temporary governance hypothesis. We discuss and conclude on our results in light of literatures on private governance, policy sectors as well as international relations theory on the emergence of international and transnational regimes.