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This paper provides an innovative approach to assessing carbon sequestration in sweet chestnut coppice taking into account the importance of carbon fluxes in the whole forest-industry value chain in the mitigation of climate change. The goals of this study were: to evaluate the baseline carbon capture of sweet chestnut forest in the north of Spain; to assess the effect of thinning and extending the rotation period on carbon storage; and to evaluate the substitution effect of using sweet chestnut products as an alternative to other materials. The CO2FIX model was used to estimate carbon content in different forest components: aboveground and belowground biomass, soil and wood products, under five different thinning and rotation scenarios. Model parameterization as a function of stand age was carried out using growth data, climate data, litterfall rates, sawmill processing data, and data on the lifespan of products and their final end. Sawmill efficiency was measured in situ using the Lumber Recovery Factor. The scenarios in which only one thinning was made resulted in more total carbon accumulating than the baseline, especially when the 40 years rotation was increased by 20 years. In contrast, scenarios involving two thinning did not even reach the baseline value of total carbon. Additionally, a positive impact on GHG emissions was found for using wood to substitute other materials, i.e. cement and fossil fuel. Taken together, these results highlight the sustainability of thinning and rotation treatments in terms of carbon storage in sweet chestnut coppice, and quantifiably supports the environmental benefits of the substitution effect of sweet chestnut wood products. As such, it provides valuable information for forest managers and policy makers who wish to address climate change mitigation in forest management planning. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new methodology to build parametric models to estimate global solar irradiation adjusted to specific on-site characteristics based on the evaluation of variable importance. Thus, those variables highly correlated to solar irradiation on a site are implemented in the model and therefore, different models might be proposed under different climates. This methodology is applied in a study case in La Rioja region (northern Spain). A new model is proposed and evaluated on stability and accuracy against a review of twenty-two already existing parametric models based on temperatures and rainfall in seventeen meteorological stations in La Rioja. The methodology of model evaluation is based on bootstrapping, which leads to achieve a high level of confidence in model calibration and validation from short time series (in this case five years, from 2007 to 2011). The model proposed improves the estimates of the other twenty-two models with average mean absolute error (MAE) of 2.195 MJ/m2day and average confidence interval width (95% C.I., n = 100) of 0.261 MJ/m2day. 41.65% of the daily residuals in the case of SIAR and 20.12% in that of SOS Rioja fall within the uncertainty tolerance of the pyranometers of the two networks (10% and 5%, respectively). Relative differences between measured and estimated irradiation on an annual cumulative basis are below 4.82%. Thus, the proposed model might be useful to estimate annual sums of global solar irradiation, reaching insignificant differences between measurements from pyranometers. [Copyright &y& Elsevier]

Abstract: The paper by Martín-Chivelet et al. (2011) presents a temperature reconstruction for the past 4000yr based on the δ13C record of three speleothems from different caves in northern Spain. I consider that the record of these speleothems cannot provide a reliable temperature reconstruction due to the lack of: (1) an adequate calibration (2) a mechanism able to explain the observed δ13C signal variability in terms of surface air temperature (SAT) and (3) a clear correlation when the record is quantitatively compared with other thermal reconstructions. Instead, the δ13C signal in these speleothems responds to a series of factors and not a single control. Some of these controls are known to be affected by factors other than SAT and could dominate the δ13C signal explaining the lack of correlation with other palaeotemperature compilation records. Therefore, a palaeotemperature reconstruction from these samples is thought to be unreliable. [Copyright &y& Elsevier]

Abstract: Ecosystem goods and services have been brought to the forefront of policy making all over the world. It is acknowledged that these goods and services underpin human well-being. The provision of water resources is amongst those services that have raised more attention, given its unquestionable value and global threats like climatic change. Nevertheless, the biophysical basis that determines the land-use/water interactions has been often ignored. For the formulation of sound decisions, it is necessary to extend the empirical basis that determines these complex relations. With this aim, the present paper analyses the effect of alternative types of land cover in the provision of water resources. In doing so, we compare hydrological, meteorological and land-cover data obtained in 15 watersheds located in the Basque Country (Northern Spain). Moreover we discuss the implications of including water resources in land-use policy and planning and address areas for further research. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to reconstruct the variation in the vegetation during the Holocene on the Northern Meseta through pollen analysis in order to determine the roles played by Pinus and Quercus in the vegetation dynamics. A new pollen sequence, Camporredondo, in the centre of the Duero River basin, Northern Meseta, Spain, is presented. It covers the period from ca 11,250 to 1630 cal yr BP. The Camporredondo sequence suggests that a forested landscape existed from the start of the Holocene with values of approximately 90% of arboreal pollen mainly derived from pine forests in the surroundings. Shortly after 8600 cal yr BP pine forests continued to dominate but the landscape became more open while stands of deciduous and evergreen Quercus developed. Around 4500 years ago, coinciding with the start of a period of less rainfall, the lacustrine areas in these territories began to silt up, favouring hydrophytic taxa such as Salix or Cyperaceae. A comparison with other Holocene pollen sequences from the central-eastern part of the Northern Meseta confirms the presence of pine forests in the whole region since the early Holocene. We discuss the variations of the general vegetation pattern in terms of the local or regional conditions at each site. Throughout the Holocene, Pinus forests dominated at least in the eastern half of the Duero River basin. The typical Holocene substitution of conifers by broadleaf species as recorded in other parts of the Iberian Peninsula and Europe, never takes place in the study area. The results of the present study suggest that the current view of the potential vegetation in the Spanish Northern Meseta should be reviewed. [Copyright &y& Elsevier]