Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Etats Unis → 2008 → Arthropod and Plant Communities as Indicators of Land Rehabilitation Effectiveness in a Semi-arid Shrub-steppe

Brigham Young University (2008)

Arthropod and Plant Communities as Indicators of Land Rehabilitation Effectiveness in a Semi-arid Shrub-steppe

Eric Ty Gardner

Titre : Arthropod and Plant Communities as Indicators of Land Rehabilitation Effectiveness in a Semi-arid Shrub-steppe

Auteur : Eric Ty Gardner

Université de soutenance : Brigham Young University

Grade : Master of Science 2008

Résumé
We describe a case study evaluating the ecological impact of Bromus tectorum L. (cheatgrass) invasion following fire disturbance and the effectiveness of revegetation in improving ecological integrity in a degraded semi-arid shrub steppe system. The effectiveness of rehabilitation efforts was assessed from measurements of arthropod richness, vegetation and arthropod community composition, and ground cover characteristics in three habitats : undisturbed, burned and weed-infested (B. tectorum), and burned and rehabilitated with native and non-native vegetation. Arthropods were collected in each habitat using pitfall traps. Differences in arthropod richness were compared using rarefaction curves. Non-metric multidimensional scaling, and non-parametric multivariate statistical procedures including analysis of similarity and similarity percentages routines were used to compare arthropod and vegetation community composition and ground cover characteristics between habitats. Arthropod communities in the rehabilitated habitat were distinct from and intermediate to those observed in the undisturbed and weed-infested habitats. Rehabilitation in this instance resulted in an improvement in ecological integrity and perhaps an intermediate step on the way complete restoration. Arthropod richness, arthropod and vegetation community composition, and ground cover characteristics were all useful indicators of ecological integrity, but returned slightly different results. Assessing multiple variables yielded the most complete understanding of the habitats studied.

Présentation

Version intégrale (0,84 Mb)

Page publiée le 21 mars 2010, mise à jour le 10 novembre 2018