Slow recovery in desert perennial vegetation following prolonged human disturbance
Citation
Qinfeng Guo, Slow recovery in desert perennial vegetation following prolonged human disturbance: .
Summary
Questions: How long may it take for desert perennial vegetation to recover from prolonged human disturbance and how do different plant community variables (i.e. diversity, density and cover) change during the recovery process? Location: Sonoran Desert, Arizona, USA. Methods: Since protection from grazing from 1907 onwards, plant diversity, density and cover of perennial species were monitored intermittently on ten 10 m × 10 m permanent plots on Tumamoc Hill, Tucson, Arizona, USA. Results: The study shows an exceptionally slow recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s [...]
Summary
Questions: How long may it take for desert perennial vegetation to
recover from prolonged human disturbance and how do different plant
community variables (i.e. diversity, density and cover) change during
the recovery process? Location: Sonoran Desert, Arizona, USA. Methods:
Since protection from grazing from 1907 onwards, plant diversity,
density and cover of perennial species were monitored intermittently on
ten 10 m × 10 m permanent plots on Tumamoc Hill, Tucson,
Arizona, USA. Results: The study shows an exceptionally slow recovery
of perennial vegetation from prolonged heavy grazing and other human
impacts. Since protection, overall species richness and habitat
heterogeneity at the study site continued to increase until the 1960s
when diversity, density and cover had been stabilized. During the same
period, overall plant density and cover also increased. Species turnover
increased gradually with time but no significant relation between any of
the three community variables and precipitation or Palmer Drought
Severity Index (PDSI) was detected. Conclusions: It took more than 50
yr for the perennial vegetation to recover from prolonged human
disturbance. The increases in plant species richness, density, and cover
of the perennial vegetation were mostly due to the increase of
herbaceous species, especially palatable species. The lack of a clear
relationship between environment (e.g. precipitation) and community
variables suggests that site history and plant life history must be
taken into account in examining the nature of vegetation recovery
processes after disturbance. Published in Journal of Vegetation Science,
volume 15, issue 6, on pages 757 - 762, in 2004.