Continuing decline of a keystone tree species in the Kruger National Park, South Africa

作者: Chantal V. Helm , Ed T. F. Witkowski

DOI: 10.1111/AJE.12032

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摘要: Sclerocarya birrea subsp. caffra (marula), a keystone large tree species in southern Africa and heavily utilized by people herbivores, is declining at an unprecedented rate the Kruger National Park (KNP), South Africa. Due to increasing concerns over declines KNP, mirroring those eastern last 50 years, local extinctions of marula populations north-western adult trees KNP were monitored between 2001 2010. Annual mortality rates across all size classes ranged 3.2 4.6%. Loss some areas decade exceeded 25%. Rainfall had strong influence on temporally spatially, but distance nearest perennial river little influence. Overall, continue decline further are possible. Given clearly unacceptable trends decline, next step utilize this information (i) develop predictive models for future dynamics incorporating drivers; (ii) advocate active management refugia within park where protected from elephant impacts; combination with (iii) continued monitoring. Resume Le un grand arbre essentiel en Afrique australe et orientale qui est largement utilise par les hommes train de decliner rythme sans precedent dans le Parc (PNK), du Sud. Vu l'inquietude croissante au sujet declin des grands arbres PNK, comparable celui constate l'Est cours 50 dernieres annees, locales marulas nord-ouest adultes sud PNK ont ete suivis entre Le taux mortalite annuel, toutes d'âge adulte, allait 3,2 4,6%. La perte d'arbres depasse 25% certaines regions la derniere decennie. Les chutes pluie eu une grande sur mortalite, aussi bien temps que l'espace, mais rapport plus proche riviere permanente avait peu d'influence. Partout continuent decliner, nouvelles sont possibles. Etant donne cette tendance declinante inacceptable, l'etape suivante consiste utiliser ces informations pour : 1) developper modeles predictifs pour dynamique integrant tous facteurs impliques ; 2) plaider gestion refuges parc ou seront protegees l'impact elephants ; combinaison avec 3) suivi continu.

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