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DAMAGE REDUCTION. "All these changes are meant to balance the partitioning of energy at the photosystem level between photochemical and non-photochemical processes, so the excitation pressure at the photosystem II and damage to reaction centres can be reduced." https://lnkd.in/eYuQ_dT View in LinkedIn

THERMAL DISSIPATION. "Evergreen leaves also alter the energy partitioning at the photosystem level modifying the contribution of dynamic and sustainable thermal dissipation processes that are strongly regulated by light and temperature." View in LinkedIn

RESTRUCTURING OPTIONS. "Some of the changes concern restructuring and changes in size of photon-capturing antennae, and some are related to modifications in the quantity of chlorophylls, non-photosynthetic pigments, photosystem II light harvesting complexes and reaction centres." https://lnkd.in/eYuQ_dT View in LinkedIn

DRASTIC ANNUAL RESTRUCTURING. "Thus, leaves of evergreen plants need to cope with the variation in environmental conditions, typical for the northern and alpine regions. In order to ensure the integrity of the photosynthetic apparatus, Scots pine needles undergo drastic seasonal structural and molecular changes at the photosystem level." https://lnkd.in/eYuQ_dT View in LinkedIn

ENDURING PINE NEEDLES. "Unlike deciduous plants, overwintering ever-green plants do not shed their leaves annually but retain them for several years. For example, in Scots pine from boreal and sub-boreal regions...eight-year-old needles can be found." View in LinkedIn

ENERGY DISSIPATION. "In order to maintain the photosynthetic energy balance, leaves have mechanisms to modulate the absorption of radiation and the capacity to harmlessly dissipate the energy absorbed in excess. In the short term, many plants species change the orientation of leaves and reposition chloroplasts inside the cells to minimize harmful quantities of light." https://lnkd.in/eYuQ_dT View in LinkedIn

PHOTON EXCESS. "At subfreezing temperatures, net photosynthesis in white pine approaches zero, and photodynamic damage to the chloroplast can occur if energy from absorbed photons is not dissipated." https://lnkd.in/eqkRiKP View in LinkedIn

SEASONAL STRESSORS. "Throughout its growing range, this evergreen species is exposed to subfreezing temperatures that range from -10 to -30°C during the winter and high temperatures exceeding 30°C during the summer. These extremes are generally indicative of conditions leading to photo-oxidative stress, especially during periods of high irradiance and reduced CO2 fixation, when the primary sink for the removal of electrons from PSI is limited." (Eastern White Pine). https://lnkd.in/eqkRiKP View in LinkedIn

HIGHER PHOTOSYNTHESIS. "A study in Germany compared energy production in beech trees (which have broad, flat leaves) and Norway spruce trees (which have needles). It was found that the beech trees photosynthesize for 176 days in a year while the Norway spruce photosynthesize 260 days in a year! The bottom energy line was that with this increased time base for photosynthesis, the smaller leafed surface area of the Norway spruce was actually 58% more productive than the beech!" https://lnkd.in/evhFvqV View in LinkedIn

SPECIALIZED LEAVES. "Needle-shaped leaves have a very low light absorptive surface area. Each needle, then, is not able to capture very much sunlight energy for photosynthesis. Needles also have a very thick, outer cuticle coating and special "pit-like" stomatae designed to prevent excessive water loss. Trees with needle-shaped leaves are especially well suited to site's that have drier soils and to climates in which the careful conservation of water is an important survival strategy." https://lnkd.in/evhFvqV View in LinkedIn