Effect of manure composition on seedling emergence and growth of two common shrub species of Southeast Alaska

摘要: Theidea that fecal material accompanying vertebrate-dispersed seeds at depositionsites plays an important role in enhancing seed germination and seedlingsurvival has, surprisingly, little empirical support. The present studyattemptsto experimentally test this hypothesis. We examined the effect manurecomposition from brown bears (Ursus arctos), importantseeddispersers of Rubus spectabilis Vacciniumovalifolium/alaskaense temperate rainforests SoutheastAlaska, has on seedling emergence growth these two fleshy-fruitedspeciesin their natural habitat. spectabilisshowed a significantly higher rate manure composed animalmaterial (mainly deer hair bones) than consisting either fruitpulp or vegetation fiber controls (potting soil with no manureadded). final number germinated wassimilar between animal fruit pulp treatments, perhaps dueto similar water retention capacities, but was thevegetation treatment control. patterns ofVaccinium seeds, contrast, appeared to be unaffected bythe composition which they were embedded. Seedlings bothspeciesgrew faster, case produced moreleaves,when consisted material. A principal constituent bone iscalcium phosphate, may provide minerals growing plants.Manure containing also enhanced compared tomanure For Rubus, manurewith did not affect length significantly, although thenumber leaves per greater thecontrol. conclude influence frugivores fate seedsof fleshy-fruited plants appears depend only upon commonly consideredfactors such as distance dispersal, digestive tract, andlocation deposition, what dispersed areembedded in, i.e., other food have consumed along thefruits.