Restoring Native Forest Understory: The Influence of Ferns and Light in a Hawaiian Experiment

Sustainability

Rachelle K. Gould²  Harold Mooney³  Laura Nelson¹  Robert Shallenberger⁴ 

[1] P.O. Box 514, Holualoa, HI 96725, USA; E-Mail:;Emmett Interdisciplinary Program in Environment and Resources, Stanford University, 473 Via Ortega, Stanford, CA 94305, USA;Department of Biology, Stanford University, 371 Serra Mall, Stanford, CA 94305, USA; E-Mails:;P.O. Box 6779, Kamuela, HI 96743, USA; E-Mail:

关键词: ʻalalā (Hawaiian Crow;    Corvus hawaiiensis);    biodiversity conservation;    economic costs of restoration;    interspecific facilitation;    land-use change;    pasture;    private lands;    tropical forest restoration;   

DOI  :  10.3390/su5031317

来源: mdpi

【 摘 要 】

Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1) overstory shade and (2) possible facilitation by a fern (Dryopteris wallichiana), one of few native colonists of pasture in our montane Hawaiʻi study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings survived. Seedling survivorship was significantly higher in the presence of a fern (79% vs. 71% without a fern) and in medium and low light conditions (81% vs. 64% in high light). Relative height was highest at low to medium light levels. After 2.2 years, 2.8% of the planted seeds germinated. We observed no significant differences in seed germination relative to light level or fern presence. Analyzing several approaches, we found nursery germination of seeds followed by outplanting ca. 20% less costly than direct seeding in the field. This study opens new questions about facilitation mechanisms that have the potential to increase the extent and effectiveness of restoration efforts.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.