Hydraulic properties control plant responses to climate and are likely to be under strong selective pressure, but their macro-evolutionary history remains poorly characterised. To fill this gap, we compiled a global dataset of hydraulic traits describing xylem conductivity (K s), xylem resistance to embolism (P50), sapwood allocation relative to leaf area (Hv) and drought exposure (w min), and matched it with global seed plant phylogenies. Individually, these traits present medium to high levels of phylogenetic signal, partly related to environmental selective pressures shaping lineage evolution. Most of these traits evolved independently of each other, being co-selected by the same environmental pressures. However, the evolutionary correlations between P50 and w min and between K s and Hv show signs of deeper evolutionary integration because of functional, developmental or genetic constraints, conforming to evolutionary modules. We do not detect evolutionary integration between conductivity and resistance to embolism, rejecting a hardwired trade-off for this pair of traits.

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Hydraulic properties control plant responses to climate and are likely to be under strong selective pressure, but their macroevolutionary history remains poorly characterized. We compiled a global dataset of hydraulic traits describing xylem efficiency, xylem safety, sapwood allocation relative to leaf area and drought exposure and matched it with a newly derived genus-level phylogeny to shed light on woody-plant hydraulic eco-evolutionary patterns. All hydraulic traits present medium to high levels of phylogenetic signal, being evolutionarily segregated into two phylogenetically conserved adaptive modules: the safety-exposure coordination, whereby lineages exposed to drought adapted to withstand low water potentials by evolving a xylem with higher embolism resistance; and the efficiency-allocation coordination, whereby higher water availability and deeper, water-retentive soils led to the evolution of hydraulically efficient species with higher leaf area relative to sapwood area. Moreover, the lack of evolutionary correlation between xylem safety and efficiency suggest that both adaptive modules are independent.

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<p>The sapwood area supporting a given leaf area (<em>v</em><sub>H</sub>) reflects a coordinated coupling between carbon uptake, water transport and loss at a whole plant level. Worldwide variation in <em>v</em><sub>H</sub> reflects diverse plants strategies adapt to prevailing environments, and impact the evolution of global carbon and water cycles. Why such a variation has not been convincingly explained yet, thus hinder its representation in Earth System Models. Here we hypothese that optimal <em>v</em><sub>H</sub> tends to mediate between sapwood conductance and climates so that leaf water loss matches both sapwood hydraulics and leaf photosynthesis. By compiling and testing against two extensive datasets, we show that our hypothesis explains nearly 60% of <em>v</em><sub>H</sub> variation responding to light, vapor pressure deficit, temperature, and sapwood conductance in a quantitively predictable manner. Sapwood conductance or warming-enhanced hydraulic efficiency reduces the demand on sapwood area for a given total leaf area and, whereas brightening and air dryness enhance photosynthetic capacities consequently increasing the demand. This knowledge can enrich Earth System Models where carbon allocation and water hydraulics play key roles in predicting future climate-carbon feedback.</p>

In the context of power loads a wind turbine based on a BLDC motor will be programmed and simulated in PSIM, as well as Power designs and control strategies. A three-phase power inverter for trapezoidal control of a BLDC motor will be developed. Electronic control of the motor is implemented in a MCU and this will simulate the behaviour of a wind turbine using the given input data. The Inverter will protect the motor against an overcurrent. Inverter will be powered by the 48 V DC bus. The three-phase inverter will be designed from a high-frequency MOSFET transistor, the IRF540, and a commercial driver, the IR2110. In order to implement the control unit, a dsPIC30F3010 Microchip microcontroller programmed in CSS will be used. The developed module has an educational purpose and is integrated in a scale size workbench for renewable energies in order to evaluate and test power modules and control strategies on smart grids powered by renewable energies.

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