Ecosystem services must tackle anthropized ecosystems and ecological engineering

- The notion of ecosystem service has never been applied in a consistent way to anthropized ecosystems.
- Human manipulations and natural ecological processes are tightly intermingled.
- Services arising solely from ecological processes cannot be separated from the result of human manipulations.
- We must jointly assess ecological services, disservices and environmental impacts of ecological manipulations.
- The framework we propose constitutes a consistent way to assess and compare different practices of ecological engineering.

The notion of ecosystem service is meant to better link human societies to ecological systems and to serve has a tool for decision making. However, the notion has never been applied in a comprehensive and consistent way to anthropized ecosystems while most ecosystems are indeed anthropized. This means that in initiatives of ecosystem service assessment anthropized ecosystems are either neglected or their services assessed in a misleading way. For example, services from cultivated lands are usually valued through the value of the agricultural production, while this production highly depends on inputs (fertilizers, pesticides, non-renewable sources of energy) and human work that cannot be assimilated to ecological factors. Moreover, these practices have negative impacts such as the emission of greenhouse gases, nutrient leaching to other ecosystems or loss of soil fertility. Hence, we present here a general framework that could be used to assess the ecosystem services provided by anthropized ecosystems. This framework is based on the joint assessment of ecological services, disservices, losses of natural capital and impacts on other ecosystems. We show that this framework is required to assess different practices to manipulate an ecosystem, e.g. low- vs high-input agriculture, or different ecosystems with different levels of anthropization, e.g. manage forest vs. cropland. Indeed, ecosystems function in such a complex way that human manipulations and natural ecological processes are tightly intermingled so that services and disservices arising solely from ecological processes cannot be separated from the result of human manipulations.