0198566123.pdf

NATURAL DISTURBANCE ON ISLANDS 39

Environmental disturbance

regimes

Biotic responses

Evolution of

the biota

Ecosystem change

Speciation

Extinction

Secondary

succession

Gap-phase

replacement

Competition

*Disturbance events Productivity

Soil development

Plate

tectonics

100

100

103

106

109

104 108

Temporal scale (years)

1012 100

Spatial scale (m^2 )

*Examples:

Wildfire, wind damage,

flood, earthquake

104 108 1012

Glacial-

interglacial

climatic cycles

Human activities

Fire regime

Pathogen outbreak

Species migration

Climatic fluctuations

Figure 2.20Environmental disturbance regimes and biotic responses, viewed in the context of four space–time domains (shown here bounded
by dashed lines), named micro-, meso-, macro-, and mega-scales by the scheme’s authors. (Redrawn from Delcourt and Delcourt 1991, Fig. 1.6;
from an original in Delcourt and Delcourt 1988, with kind permission from Kluwer Academic Publishers.)

Table 2.5Disturbance phenomena affecting Caribbean islands (after Lugo 1988). See text for explanation of the five types

Disturbance Type Area Primary Duration Recurrence
phenomena affected impact

Hurricanes 3, 5 Large Mechanical Hours–days 20–30 years
High winds 3, 4, 5 Large Mechanical Hours Annual
High rainfall 4 Large Physiological Hours Decade
High-pressure systems 1 Large Physiological Days–weeks Decades
Earthquakes 2, 5 Small Mechanical Minutes 102 years
Volcanism All Small Mechanical Months–years 103 years
Tsunamis 3, 4, 5 Small Mechanical Days 102 years
Extreme low tides 1 Small Physiological Hours–days Decades
Extreme high tides 3, 4, 5 Small Mechanical Days–weeks 1–10 years
Exotic genetic material 2, 3 Large Biotic 102 years Decades
Human, e.g. energy 1 Small Biotic Years 1–10 years
Human, e.g. war 5 Small Mechanical Months–years?