A preliminary spatial quantification of the soil security dimensions for Tasmania

Abstract

Soil Security is a holistic soil assessment approach that cogitates soil as a multi-dimensional medium. Rather than traditional single dimensional assessment approaches such as land capability mapping that largely considers only soil and landscape biophysical attributes, the Soil Security concept considers social aspects, education, policy, legislation, current land use, condition and the soils natural and economic value to society. It can identify discrete soils that are currently being used within their capacity, and areas where a use might be unsustainable, i.e. not secure. It would therefore make sense to map this concept, which aligns well with the aspirational and marketing policies of the Tasmanian Government, where increased agricultural expansion through new irrigation schemes and multiple-use State managed production forests co-exists beside pristine World Heritage conservation land, a major drawcard of the economically important tourism industry. The spatial quantification of soil security is seen as an emerging tool to effectively protect the soil resource in terms of food and water security, biodiversity maintenance and safeguarding fragile ecosystems. The recent development and application of Digital Soil Mapping and Assessment capacities in Tasmania to stimulate agricultural production and better target appropriate soil resource use has formed the foundational system that can enable the first efforts in quantifying and mapping Soil Security, in particular the five Soil Security dimensions (Capability, Condition, Capital, Codification and Connectivity). This forms a preliminary mapping product that demonstrates the feasibility of mapping the Soil Security concept. To provide a measure of overall soil security, it was necessary to separately assess the State’s three major soil uses; Agriculture, Conservation and Forestry. These outputs provide an indication of where different activities are sustainable or at risk, where more soil data is needed, and develops a tool to better plan for a State requiring optimal food and fibre production, without depleting its natural soil resources and impacting the fragile ecosystems providing environmental benefits and supporting the tourism industry. The following paper demonstrates why and how we might map Soil Security, describing a preliminary approach to mapping the separate dimensions; this approach could be adapted and applied elsewhere as an evaluation tool to identify soil threats relevant to current land use, biophysical properties, policy and management, and stimulate further research and debate into developing a global Soil Security mapping methodology.