An economical non-destructive method for estimating eelgrass, Zostera marina (Potamogetonaceae) leaf growth rates: formal development and use in northwestern Baja California.
Seagrass beds provide much of the primary production in estuaries; host many fishes and fish larvae, and abate erosion. The present study presents original analytical methods for estimating mean leaf-growth rates of eelgrass (Zostera marina). The method was calibrated by using data collected in a Z. marina meadow at Punta Banda estuary in Baja California, Mexico. The analytical assessments were based on measurements of leaf length and standard regression procedures. We present a detailed explanation of the formal procedures involved in the derivation of these analytical methods. The measured daily leaf-growth rate was 10.9 mm d(-1) leaf(-1). The corresponding value projected by our method was 10.2 mm d(-1) leaf(-). The associated standard errors were of 0.53 and 0.56 mm d(-1) leaf(-1) respectively. The method was validated by projecting leaf-growth rates from an independent data set, which gave consistent results. The use of the method to obtain the mean leaf growth rate of a transplanted plot is also illustrated. Comparison of our leaf-growth data with previously reported assessments show the significant forcing of sea-surface temperature on eelgrass leaf dynamics. The formal constructs provided here are of general scope and can be applied to equivalent eelgrass data sets in a straightforward manner.
Departamento de Ecología Marina, Centro de Investigación Científica y Educación Superior de Ensenada, P.O. Box 434844, San Diego CA 92143-4844, California, USA. esolana@cicese.mx
Elena
E
Solana-Arellano
Héctor
H
Echavarria-Heras
Ernesto
E
Franco-Vizcaíno
D004784:Environmental Monitoring / Q000191:economics / Q000379:methods*; D008800:Mexico; D008954:Models, Biological; D018515:Plant Leaves / Q000254:growth & development*; D012621:Seasons; D035962:Zosteraceae / Q000254:growth & development*