Carbon sequestration in intensive hardwood plantations: influence of management

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Interactions among plant layers in shrub-encroached Iberian dehesas and consequences for their persistance

PosterWe analyze the effect of shrub understory on the functioning and persistence of Iberian dehesas (grazed open woodlands). We study the effect of two contrasting, in terms of morphological traits and reproductive strategy, shrub species: Retama sphaerocarpa (a deep rooted shrub) and Citus ladanifer (a shallow rooted shrub), in order to account for specie-specific effects, on neighboring vegetation (tree and pasture). Pasture and tree rooting profile, soil resources availability (water and nutrients), tree and pasture production, tree physiological status and tree regeneration were assessed with and without the presence of shrubs. The results showed that the presence of shrubs deeply modify tree and pasture root systems. Trees growing either with Cistus or Retama exhibited a significantly deeper rooting profile than growing without competition, whereas herbaceous species showed the opposite trend, shifting most of their roots upwards to shallower soil horizons. Cistus appeared to be a great competitor for soil resources, what led to significantly lower tree leaf water potential, leaf gas exchange parameters, acorn production and growth. Cistus encroachment also reduced pasture yield by 68 to 98 %. Retama ameliorated top soil fertility and showed positive effect on soil moisture. Retama increased significantly pasture yield by 11 to 157 % and tree growth by 6 to 13 %, but had a neutral to negative effect on acorn yield. Both shrubs showed a similar positive effect on tree seedling emergence in spring and survivorship after summer. However, as seedling aged, this positive association strengthened with Retama and weakened over time with Cistus. To sum up, shrubs have the potential to modify the functioning and persistence of Mediterranean open oak woodlands. Thus, future management practices must bear in mind this specificity of effects and try to optimize the positive effect of shrubs without jeopardizing the productivity or functioning of the system

Silvopastoral management for quality wood production

PosterIn the last decade, hardwood plantations have substantially increased in many Spanish regions. In order to grow trees for high quality timber in short rotations, an intensive management, with high economic and environmental costs. The control of competing herbaceous vegetation is required for avoiding tree-herbage competition and fire risk. Silvopastoral management could allow reducing the economic costs and optimize their environmental functions. This study was carried out in various intensive 15 year old plantations of walnut located in Extremadura (Spain). A comparison of different herbaceous layer control was realized: harrow, brushcutter and grazing on natural grassland combined with different doses of irrigation. The objective of this study is to evaluate the profitability of each technique and their environmental implications. The nutritional and physiological status of trees was analyzed, as well as their growth (diameter increment). In addition, the temporal dynamics of soil moisture profile, available nutrients in the soil and nitrate leaching were studied. The maximum tree growth was observed with harrowing (where the highest available N and Ca in soil were observed) and grazing treatment (where P availability in soil was increased) both combined with the highest level of irrigation (that produced an increment of P and K content in leaves). The lowest tree growth was observed with brushcutting, in spite of this treatment, as horrowing, improved the N leaf level. Moreover, brushcutting affected positively to organic matter content and produced the lowest nitrate leaching in soil (in the first 30 cm depth). Respect to nitrate leaching, the difference among treatments was not significantly below 30 cm deep which reduces environmental hazard. There was no difference in physiological status of trees and soil moisture. Therefore, silvopastoral systems can be compatible with the medium-long term hardwood timber production, with great current and future demand, developing an environmentally efficient production system

The role of scattered trees and habitat diversity for biodiversity of Iberian dehesas

PosterWe studied 10 dehesas of CW Spain (40º 00’-10’ N, 06º 10’-20’ W), mapping every habitat according to a standardized protocol developed by the European BioBio project. We defined 35 habitat types, with 19 habitat types (split in 85 plots) per dehesa, on average. In one randomly selected plot per habitat type diversity of the four taxa, plants, bees, spiders and earthworms, were assessed. In total, 450 plant species (average of 189 per farm and 36 per habitat), 63 bee species (17.6 and 3.2), 130 spider species (43.8 and 7.4), and 17 earthworm species ( 7.8 and 2.5) were recorded. In each taxa, only some species were very abundant, while most of the species were found only in few farms/habitats. A high proportion of species (ca. 40%) were observed only in just one habitat per farm, indicating that farm biodiversity strongly depends on the habitat diversity. The analysis of unique and shared species among habitats revealed that every habitat contribute significantly to farm biodiversity. By contrast, species richness was poorly explained by the presence of scattered trees, whereas the combination of wood pastures and open pastures was a significant predictor. Summarizing, our extensive survey showed that diversity of the four taxa was strongly related to the existence of a wide mosaic of habitats, including non-productive habitats and linear elements, which harbor a disproportionate number of species compared to the low area occupied. Moreover, these habitats harbor a high number of exclusive species. As a next step, the importance of the spatial arrangement of main and non-productive habitats for biodiversity at the farm and landscape levels, need to be checked

Incorporation of nio into sio2, tio2, al2o3, and na4.2ca2.8(si6o18) matrices: Medium effect on the optical properties and catalytic degradation of methylene blue

The medium effect of the optical and catalytic degradation of methylene blue was studied in the NiO/SiO2, NiO/TiO2, NiO/Al2O3, and NiO/Na4.2Ca2.8(Si6O18) composites, which were prepared by a solid-state method. The new composites were characterized by XRD (X-ray diffraction of powder), SEM/EDS, TEM, and HR-TEM. The size of the NiO nanoparticles obtained from the PSP-4-PVP (polyvinylpyrrolidone) precursors inside the different matrices follow the order of SiO2 > TiO2 > Al2O3 . However, NiO nanoparticles obtained from the chitosan precursor does not present an effect on the particle size. It was found that the medium effect of the matrices (SiO2, TiO2, Al2O3, and Na4.2Ca2.8(Si6O18)) on the photocatalytic methylene blue degradation, can be described as a specific interaction of the NiO material acting as a semiconductor with the MxOy materials through a possible p-n junction. The highest catalytic activity was found for the TiO2 and glass composites where a favorable p-n junction was formed. The isolating character of Al2O3 and SiO2 and their non-semiconductor behavior preclude this interaction to form a p-n junction, and thus a lower catalytic activity. NiO/SiO2 and NiO/Na4.2Ca2.8(Si6O18) showed a similar photocatalytic behavior. On the other hand, the effect of the matrix on the optical properties for the NiO/SiO2, NiO/TiO2, NiO/Al2O3, and NiO/Na4.2Ca2.8(Si6O18) composites can be described by the different dielectric constants of the SiO2, TiO2, Al2O3, Na4.2Ca2.8(Si6O18) matrices. The maxima absorption of the composites (¿max) exhibit a direct relationship with the dielectric constants, while their semiconductor bandgap (Eg) present an inverse relationship with the dielectric constants. A direct relationship between ¿max and Eg was found from these correlations. The effect of the polymer precursor on the particle size can explain some deviations from this relationship, as the correlation between the particle size and absorption is well known. Finally, the NiO/Na4.2Ca2.8(Si6O18) composite was reported in this work for the first time

Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA

We report results of air monitoring started due to the recent natural catastrophe on 11 March 2011 in Japan and the severe ensuing damage to the Fukushima Dai-ichi nuclear reactor complex. On 17-18 March 2011, we registered the first arrival of the airborne fission products 131-I, 132-I, 132-Te, 134-Cs, and 137-Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. We measured the evolution of the activities over a period of 23 days at the end of which the activities had mostly fallen below our detection limit. The highest detected activity amounted to 4.4 +/- 1.3 mBq/m^3 of 131-I on 19-20 March.Comment: 7 pages, 5 figures, published in Journal of Environmental Radioactivit

Intra-abdominal pulmonary secuestration as an exceptional cause of abdominal mass in the adult

AbstractINTRODUCTIONPulmonary sequestration (PS) is an extremely rare malformation defined as a portion of lung tissue isolated from the pulmonary system. PSs are classified into intralobar type and intra-abdominal PS that represents only 2.5% of cases. There are 20 cases of PS reported in adults and only two were managed by laparoscopic approach. We report a case of intra-abdominal PS mimicking a gastroesophageal duplication cyst in an adult. Besides its rarity, this is the first intra-abdominal PS in an adult managed by an anterior laparoscopic approach.PRESENTATION OF CASEA 60-year-old female patient had had epigastric and left upper quadrant pain for several days. Physical examination was normal. Image test were consistent with a gastroesophageal duplication. The patient was taken to the operating room for laparoscopic exploration and resection. The pathological diagnosis was extralobar pulmonary sequestration.DISCUSSIONLess than 20 cases of PS have been reported in adults and only two cases were managed by a lateral laparoscopic approach. In contrast to these reports, we used an anterior approach due to the GEJ suspected origin of the mass.CONCLUSIONExtralobar intra-abdominal PS is an extremely rare condition during adulthood but this diagnosis should be included in the differential diagnosis of a left-sided suprarenal mass. Due to the difficulty in achieving a definitive preoperative diagnosis, surgery is recommended. Laparoscopic resection is safe and effective but careful preoperative imaging studies are recommended in order to plan the most suitable approach

Shrub encroachment of Iberian dehesas : implications on total forage productivity

The Iberian dehesa, a grazed Mediterranean open woodland, is an outstanding example of a silvopastoral system. Shrub encroachment has been proposed as an effective method to facilitate natural tree regeneration and ensure the sustainability of silvopastoral systems. At the same time, shrubs can affect both pasture understory and tree overstory production. The effects of varying intensities of shrub encroachment on the productivity of four forage components of this system—pasture, acorns, shrub browse and tree browse—were tested and the overall metabolisable energy (ME) under different scenarios of vegetation structure was calculated. Two common shrub species with contrasting plant architectures and ecological functions were studied as models: Cistus ladanifer and Retama sphaerocarpa. Cistus negatively affected acorn, tree browse and pasture production, whereas Retama positively affected pasture and browse production and was neutral for acorn production. The highest ME values were found when tree cover was ca. 70 % and C. ladanifer cover was low or R. sphaerocarpa cover was medium. The authors recommend conserving and promoting patched three-layered plots in Iberian dehesas and similar extensive silvopastoral systems where certain shrub species could simultaneously encourage the sustainability of these systems and reinforce (with R. sphaerocarpa) or maintain (with C. ladanifer) their productivity.Spanish Ministry of Science and Innovation (AGL2006-09435/FOR) and the Regional Government of Extremadura (PRI07C044).http://link.springer.com/journal/104572016-08-31hb201

Supersymmetric Model of Muon Anomalous Magnetic Moment and Neutrino Masses

We propose the novel lepton-number relationship $L_\tau = L_e + L_\mu$, which is uniquely realized by the interaction $(\hat \nu_e \hat \mu - \hat e \hat \nu_\mu) \hat \tau^c$ in supersymmetry and may account for a possibly large muon anomalous magnetic moment. Neutrino masses (with bimaximal mixing) may be generated from the spontaneous and soft breaking of this lepton symmetry.Comment: 10 pages, including 2 figure