The Ornamental Landscape as an Ecosystem: Implications for Pest Management

Abstract

Landscape, in this paper, is defined as 'a complex of geographically, functionally and historically interrelated ecosystems' (also: 'organised land'). For its planning and management, mapping of geomorphological, hydrological, and climatic conditions is crucial to understand the ecological patterns. To warrant the landscape's sustainability, its ecosystems' multiple and interdependent functions should be carefully identified on macro-, meso- and micro-level. It is argued that, whereas a natural ecosystem is homogenous, the landscape ecosystem is heterogeneous, for example in a mosaic or zoned way. Like evolution in organisms, succession in ecosystems tends do develop toward increasing independency from environmental fluctuations (increasing autonomy of the systems). On the contrary, landscape ecosystems have increasingly lost their regional autonomy over the last decades, as external input technologies became favoured. However, theories and practices of ecological (organic) agriculture, low external input oriented as they are, tend to re-enforce the local ecosystems' autonomy together with the regional identity. In the Netherlands intensive and widespread land reclamation (polders and floodplains) made hydro-ecology a major landscape-ecology determinant. Distribution patterns of floristic species are found to reflect the hydro-dynamic conditions in natural and semi-natural ecosystems. Provided that suitable knowledge on local conditions is available, they can be used as indicators of potential sites for nature regeneration and indicate landscape degradation as well. Even though potentially favouring agro-ecosystems diversity and regional autonomy, ecological types of agriculture, as currently defined by law, do only promote nature on the farm when the farmer dedicates special attention it as an additional objective of his (organic) farming.