Emerging Stress and Relative Resiliency of Giant Sequoia Groves Experiencing Multiyear Dry Periods in a Warming Climate

摘要: The relative greenness and wetness of Giant Sequoia (Sequoiadendron giganteum, SEGI) groves the surrounding Sierra Nevada, California forests were investigated using patterns in vegetation indices from Landsat imagery for period 1985-2015. Vegetation (normalized difference index) thus forest biomass increased by about 6% over that 30-year period, suggesting a 10% increase evapotranspiration. No significant change non-grove was observed. In this local temperature measurements showed an 2.2 °C. no overall long-term trend, but responded to changes annual water-year precipitation temperature. trends grove elevation dependent, with lower rain-snow transition zone (1700 – 2100 m) marking increasing trend at elevations decreasing higher elevations. 2011-2015 drought brought unprecedented drop wetness, five times 1985-2010 standard deviation; SEGI dropped 50% more than areas. Overall, larger response warming climate influence droughts on reflected effects both multi-decadal warmer drought-year temperatures evaporative demand current vegetation, plus sufficient regolith water storage rain snowmelt sustain through seasonal multi-year dry periods.