Does the exotic equal pollution? Landscape methods for solving the dilemma of using native versus non-native plant species in drylands

Abstract

There is a need to resolve methods to determine the merits of native versus non-native plant use in drylands and indeed in more temperate areas around the world. This is because whilst plant introductions may have positive objectives, they can have significant negative landscape and environmental impacts. A key discussion on this issue focuses on whether the use of non-native plant species can be considered to be pollution and pollutive based on the concept that pollution can be regarded as ‘matter out of place’. The consequences of putting the wrong plant species in the wrong place can be extremely detrimental to the landscape character, quality and value of the land, let alone the effects on ecosystem structure and functioning as well as on biodiversity. These effects can also affect human communities who may rely on the landscape, for example, for tourism. It is thus necessary that the discussion on how decisions are made in determining plant choice evolves so that the right decisions are made when planting is necessary, for the land, for nature and for the people. This discussion has been initiated through COST Action ES1104, which focused on the restoration of degraded dry and arid lands. This article discusses a number of landscape methods based on sustainability principles to determine when and where native and non-native plants could and should be used. © 2020 The Authors. Land Degradation & Development published by John Wiley & Sons Ltd