Understanding how severe disturbances and their interactions affect forests is key to projecting ecological change under a warming climate. Substantial increases in some biotic disturbances, such as bark beetle outbreaks, in temperate forest ecosystemsmay compromise recovery to a forest vegetation type (i.e., physiognomic recovery or resilience), especially if subsequent biotic disturbances (e.g., herbivory) alter recovery mechanisms. From 2005 to 2017, severe outbreaks (>90% mortality) of spruce bark beetles (SB,
It is frequently reported that overstocking of camels, cattle and goats is degrading the
Data were collected at 30 sites in the Jabal Qamar mountain range in western Dhofar, Oman.
The point‐centred quarter method was used to sample the composition, density and structure of woody vegetation. Constrained correspondence analysis was used to quantify the effects of livestock browsing on woody plant species composition, whilst effects on plant density were analysed using mixed‐effects models. Standardised major axis regression was used to examine differences in height–diameter allometry (stunting) under different stocking rates.
Fog density, topographic position and long‐term stocking rates were found to be important factors affecting woody species composition. We found lower species diversity and plant density, and higher frequencies of unpalatable species, under higher stocking rates. Juveniles showed a stronger response to stocking rates than adults, and several common species exhibited stunted morphology under high stocking rates.
Browsing by large‐bodied livestock, such as camels and cattle, can substantially alter the species composition, structure, and phytomorphology of woody vegetation in semi‐arid woodlands and forests. Juveniles are particularly susceptible to browsing which alters woody vegetation demography and inhibits regeneration potential. Our results support previous suggestions of overstocking in Dhofar and highlight the importance of swift measures to reduce livestock browsing pressure in the
- Award ID(s):
- 1617185
- NSF-PAR ID:
- 10457930
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Applied Vegetation Science
- Volume:
- 23
- Issue:
- 3
- ISSN:
- 1402-2001
- Page Range / eLocation ID:
- p. 363-376
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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