Managing plant populations in fragmented landscapes: restoration or gardening?

Abstract

Ecosystem fragmentation results in major changes in several environmental and biotic parameters that affect the ability of plant populations to persist. All stages of the plant life cycle may be influenced in either negative or positive ways by the changed biophysical settings caused by fragmentation and associated changes in the surrounding landscape. This may result in plant populations being lost or significantly reduced from patches of native vegetation, leading to the need for active management intervention. This intervention may include management of threatening processes, reversal of ecosystem degradation, or the reintroduction of plants of species that have been lost from an area. These management actions range from preventative management through to active restoration. In the present paper I explore the question of whether there is a limit to the degree of intervention that is desirable in conservation terms, beyond which we are no longer conserving but rather cultivating and gardening, i.e. creating an artificial and potentially unsustainable system. I discuss this question in relation to management of remnant vegetation in urban and agricultural settings and suggest that a careful mix of species-based and process-based management is required for us to succeed in the goal of biodiversity conservation in fragmented landscapes.