Assessing urban ecosystem condition account with object-based methods

Abstract

We present a methodology based on the System of Environmental-Economic Accounting-Ecosystems Accounting (SEEA-EA) framework to measure urban ecosystem condition accounts. This methodology allows the condition accounts of urban ecosystems to be spatially and explicitly evaluated at a detailed scale. The reference area is determined using object-based evaluation, where the reference value for each variable is set in a real geographic context rather than individual pixels.This methodology consists of the following steps: 1. Delimitation of the urban categories to be evaluated; 2. Selection of the variables that characterize the abiotic and biotic environment; 3. Establishment of the reference polygon with which to compare the condition values; 4. Calculation of weighted condition indicators; 5. Generation of a single condition index from the aggregation of the indicators.In Madrid, the areas with the highest condition levels are characterised by a significant density of trees and bird species richness. In contrast, areas with the lowest condition levels are defined by high contamination, impervious surfaces, built-up areas and major communication routes.This innovative approach to calculating urban conditions represents an advancement in local-scale urban condition accounting and offers a potentially compatible tool with current urban policy frameworks. Its applications can be various, from identifying urban problems to reviewing the effectiveness of a plan already implemented. Several advantages have been identified over other ecosystem accounting metrics. These advantages include lower operating costs, a more integrative vision, adaptability to different spatial scales, flexibility in modifying its structure, the capacity to incorporate complex urban dynamics, reduced dependence on human judgment and easier interpretation of results.

Keywords

• Urban ecosystem accounting
• Natural capital
• Condition account
• SEEA-EA
• Madrid