caa a22 4500 467885478 CHVBK 20180406152733.0 cr unu---uuuuu 170328e20061101xx s 000 0 eng 10.1007/s10021-005-0138-y doi (NATIONALLICENCE)springer-10.1007/s10021-005-0138-y Synchrony of Seed Dispersal, Hydrology and Local Climate in a Semi-arid River Reach in California [Elektronische Daten] [John Stella, John Battles, Bruce Orr, Joe McBride] The temporal availability of propagules is a critical factor in sustaining pioneer riparian tree populations along snowmelt-driven rivers because seedling establishment is strongly linked to seasonal hydrology. River regulation in semi-arid regions threatens to decouple seed development and dispersal from the discharge regime to which they evolved. Using the lower Tuolumne River as a model system, we quantified and modeled propagule availability for Populus fremontii (POFR), Salix gooddingii (SAGO), and Salix exigua (SAEX), the tree and shrub species that dominate near-channel riparian stands in the San Joaquin Basin, CA. A degree-day model was fit to field data of seasonal seed density and local temperature from three sites in 2002-2004 to predict the onset of the peak dispersal period. To evaluate historical synchrony of seed dispersal and seasonal river hydrology, we compared peak spring runoff timing to modeled peak seed release periods for the last 75 years. The peak seed release period began on May 15 for POFR (range April 23-June 10), May 30 for SAGO (range May 19-June 11) and May 31 for SAEX (range May 8-June 30). Degree-day models for the onset of seed release reduced prediction error by 40-67% over day-of-year means; the models predicted best the interannual, versus site-to-site, variation in timing. The historical analysis suggests that POFR seed release coincided with peak runoff in almost all years, whereas SAGO and SAEX dispersal occurred during the spring flood recession. The degree-day modeling approach reduce uncertainty in dispersal timing and shows potential for guiding flow releases on regulated rivers to increase riparian tree recruitment at the lowest water cost. Springer Science+Business Media, Inc., 2006 phenology nationallicence seed dispersal nationallicence degree-day model nationallicence seed longevity nationallicence germination nationallicence Populus nationallicence Salix nationallicence seedling recruitment nationallicence riparian habitat restoration nationallicence flow regulation nationallicence California central-valley nationallicence Stella John Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut Battles John Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut Orr Bruce Stillwater Sciences, 2855 Telegraph Ave., Suite 400, 94705, Berkeley, California, USA aut McBride Joe Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut Ecosystems Springer-Verlag; www.springer-ny.com 9/7(2006-11-01), 1200-1214 1432-9840 9:7<1200 2006 9 10021 https://doi.org/10.1007/s10021-005-0138-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10021-005-0138-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Stella John Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut NATIONALLICENCE 700 1- Battles John Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut NATIONALLICENCE 700 1- Orr Bruce Stillwater Sciences, 2855 Telegraph Ave., Suite 400, 94705, Berkeley, California, USA aut NATIONALLICENCE 700 1- McBride Joe Department of Environmental Science, Policy, and Management, University of California at Berkeley, 137 Mulford Hall, 94720−3114, Berkeley, California, USA aut NATIONALLICENCE 773 0- Ecosystems Springer-Verlag; www.springer-ny.com 9/7(2006-11-01), 1200-1214 1432-9840 9:7<1200 2006 9 10021 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer