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Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to traditional vegetation indices, the photochemical reflectance index (PRI) and the emission of solar-induced chlorophyll fluorescence (SIF), now measurable from space, provide a new range of opportunities to monitor the global carbon cycle using remote sensing. However, the scale mismatch between EC observations and the much coarser satellite-derived data complicate the integration of the two sources of data. The solution is to establish a network of in situ spectral measurements that can act as a bridge between EC measurements and remote-sensing data. In situ spectral measurements have already been conducted for many years at EC sites, but using variable instrumentation, setups, and measurement standards. In Europe in particular, in situ spectral measurements remain highly heterogeneous. The goal of EUROSPEC Cost Action ES0930 was to promote the development of common measuring protocols and new instruments towards establishing best practices and standardization of these measurements. In this review we describe the background and main tradeoffs of in situ spectral measurements, review the main results of EUROSPEC Cost Action, and discuss the future challenges and opportunities of in situ spectral measurements for improved estimation of local and global estimates of GPP over terrestrial ecosystems.

Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to traditional vegetation indices, the photochemical reflectance index (PRI) and the emission of solar-induced chlorophyll fluorescence (SIF), now measurable from space, provide a new range of opportunities to monitor the global carbon cycle using remote sensing. However, the scale mismatch between EC observations and the much coarser satellite-derived data complicates the integration of the two sources of data. The solution is to establish a network of in situ spectral measurements that can act as bridge between EC measurements and remote sensing data. In situ spectral measurements have been already conducted for many years at EC sites, but using variable instrumentation, setups, and measurement standards. In Europe in particular, in situ spectral measurements remain highly heterogeneous. The goal of EUROSPEC Cost Action ES0930 was to promote the development of common measuring protocols and new instruments towards establishing best practices and standardization of in situ spectral measurements. In this review we describe the background and main tradeoffs of in situ spectral measurements, review the main results of EUROSPEC Cost Action, and discuss the future challenges and opportunities of in situ spectral measurements for improved estimation of local and global carbon cycle.

The GLObal ReactIon Array (GLORIA) has been designed in order to study direct nuclear reactions induced by exotic nuclei at energies close to the Coulomb barrier. The detector array consists of six silicon particle-telescopes arranged in a very close geometry around a 30° rotated-target system, allowing the measurement of reaction fragments in a continuous angular range from 15° to 165° (Lab.). GLORIA has been used for the first time at the SPIRAL/GANIL facility at Caen (France) to study the scattering of the system 8He+208Pb at the collision energies of 16 and 22 MeV.

The direct estimation of nitrogen (N) in fresh vegetation is challenging due to its weak influence on leaf reflectance and the overlaps with absorption features of other compounds. Different empirical modelsrelate in this work leaf nitrogen concentration ([N]Leaf) on Holm oak to leaf reflectance as well as derivedspectral indices such as normalized difference indices (NDIs), the three bands indices (TBIs) and indices previously used to predict leaf N and chlorophyll. The models were calibrated and assessed their accuracy, robustness and the strength of relationship when other biochemicals were considered. Red edge was the spectral region most strongly correlated with [N]Leaf, whereas most of the published spectral indexesdid not provide accurate estimations. NDIs and TBIs based models could achieve robust and acceptableaccuracies (TBI1310,1720,730 R2= 0.76, [0.64,0.86]; RMSE (%) = 9.36, [7.04,12.83]). These models sometimesincluded indices with bands close to absorption features of N bonds or nitrogenous compounds, but also of other biochemicals. Models were independently and inter-annually validated using the bootstrap method, which allowed discarding those models non-robust across different years. Partial correlationanalysis revealed that spectral estimators did not strongly respond to [N]Leaf but to other leaf variablessuch as chlorophyll and water, even if bands close to absorption features of N bonds or compounds werepresent in the models. © 2013 Elsevier B.V.

In this paper we describe a compact and large solid-angle silicon array, the GLObal ReactIon Array (GLORIA), designed to study direct nuclear reactions induced by exotic nuclei at energies close to the Coulomb barrier. The detector array consists of six particle-telescopes arranged in a very close geometry around a 30° rotated-target system, allowing for the measurement of reaction fragments in a continuous angular range from 15° to 165° (Lab). GLORIA has been used for first time at the SPIRAL/GANIL facility at Caen (France) to study the scattering of the system 8He+208Pb at the collision energies of 16 and 22 MeV.

The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reported.

We describe the results of an experiment designed to compare the radiometric performance of four different spectroradiometers in ideal field conditions. A carefully designed experiment where instruments were simultaneously triggered was used to measure the Hemispherical Conical Reflectance Factors (HCRF) of four targets of varying reflectance. The experiment was in two parts. Stage 1 covered a 2 hour period finishing at solar noon, where 50 measurements of the targets were collected in sequence. Stage 2 comprised 10 rapid sequential measurements over each target. We applied a method for normalising full width half maximum (FWHM) differences between the instruments, which was a source of variability in the raw data. The work allowed us to determine data reproducibility, and we found that lower-cost instruments (Ocean Optics and PP Systems) produced data of similar radiometric quality to those manufactured by Analytical Spectral Devices (ASD –here we used the ASD FieldSpec Pro) in the spectral range 400-850 nm, which is the most significant region for research communities interested in measuring vegetation dynamics. Over the longer time-series there were changes in HCRF caused by the structural and spectral characteristics of some targets.

The dynamics of 8He around the Coulomb barrier is investigated by measuring the energy and angular distribution of the elastic 8He and the 6He and 4He fragment yields in the collision process with a 208Pb target. The experiment was carried out at SPIRAL/GANIL in October 2010. The experimental results will provide information about the relevant reaction mechanisms and the validity of the optical model (OM) when applied to exotic nuclei. In this paper, details of the experimental setup and preliminary results on the elastic scattering for the collision at 22 MeV are presented.

The Centro Nacional de Aceleradores (CNA) in Sevilla-Spain currently contains three accelerators: two tandems and a compact 18/9 cyclotron. Next year, a 60Co irradiation system will also be installed. This equipment will expand the range of irradiation experiments in the Centre using both charged particles as well as gamma-ray photons. Originally, based on the 3 MV tandem accelerator, the CNA was considered as a multidisciplinary research Centre devoted basically to the materials characterization by IBA techniques. Nowadays, the validity of our low-energy accelerators has been verified not only to perform analysis but also for irradiation testing, a very promising field of work since radiation effects are aggravated with the technology decreasing scales. In this work, the last innovations and modifications of our laboratory will be briefly described, emphasizing with respect to high energy PIXE experiments and its versatility to carry out irradiation tests.

The experimental study of the fusion of light neutron-rich nucleus 8He with 206Pb is reported in this work. A fusion stack of 206Pb targets has been used for this study. The most prominent evaporation residue (210Po), which has half-life of 138 days and decays by alpha emission, is populated in the reaction. Radiochemical analysis technique is used to extract the yield of this evaporation residue.

Organic farming can be seen as a whole innovation approach, but we can also find some single improved practices which can be diseminanted to other farmers in other regions.In this paper several innovations used in the production chain of olive trees in Spain have been identified in an inquiry made to 200 organic olive oil producers/processors. Some of this innovations were selected and discussed in detail regarding it´s adoption at the expert workshop organised by the Biolmed Project in the framework of the First Spanish Organic Olive oil production Symposium in Córdoba (Spain). The results of this discussions and the reference compilation about the selected innovations are presented here with a shortly description, adventages/disaventages, experiences and information sources. Most of the selected innovations in production methods can be easily adopted by organic farmers

Particle radiation effects are a fundamental problem in the use of numerous electronic devices for space applications, which is aggravated with the technology shrinking towards smaller and smaller scales. The suitability of low-energy accelerators for irradiation testing is being considered nowadays. Moreover, the possibility to use a nuclear microprobe, with a lateral resolution of a few microns, allows us to evaluate the behavior under ion irradiation of specific elements in an electronic device. The CEICI is the new CEnter for Integrated Circuits Irradiation tests, created into the facilities at the Centro Nacional de Aceleradores (CNA) in Sevilla-Spain. We have verified that our 3 MV Tandem accelerator, typically used for ion beam characterization of materials, is also a valuable tool to perform irradiation experiments in the low LET (Linear Energy Transfer) region.