If we want to manage forests for maximum welfare outcomes, we need to boost the provision of bundled forest ecosystem services. But to get there, we first need to know where different ecosystem services are happening most, so we can set our priorities for where in space our forest conservation and management efforts are most needed.
José (Pipo) Roces-Días (CREAF & Swansea University) collaborated with a large and multidisciplinary team of a dozen co-authors to do exactly that, in an interesting research piece published recently in the journal Ecological Indicators. At the fairly coarse scale of municipalities in Catalonia (NE Iberian Peninsula), they have quantified 12 different ecosystem services from an integrated perspective in a spatially explicit manner.
Going beyond the rough proxies of forest coverage and quality that are often used in these studies, they combined forest surveys, ecological model predictions and official statistics, together with land cover information. Their indicators span widely across the forest ecosystem service spectrum, from the so-called “provisioning services” (wood and non-wood forest products), to “regulating services” (hydrological, carbon storage – above and below ground – and erosion control), and “cultural services” (recreational, landscape and existence values).
The resulting map for forest ecosystem services in Catalonia is interesting. Unlike in many other studies mapping ecosystem services, we do not see a picture of strong trade-offs between service peaks: provisioning, regulating, and in part also cultural ecosystem services all correlate positively. They are obviously linked by areas with high overall ecosystem productivity and biomass production, especially located in the northern, mountainous region of Catalonia.
These hotspots of ecosystem services are typically characterised by a fairly wet and cool climate, by Catalan standards. They are also less densely populated than average Catalonia, and there is less agriculture to compete with forest cover. This high-service cluster also correlates with high levels of biodiversity. In turn, a slight exception from the clustering are cultural ecosystem services (recreation, landscape, and existence values), which, not unexpectedly, correlate more with greater human presence and usage, such as occurs in peri-urban areas, and thus also have more of a general correlation with the service economy.
Using municipalities as a study unit has the advantage of linking directly to administrative structures that are responsible for land-use planning and forest management. Surely, if a forest manager was to zoom in to a finer spatial scale, more trade-offs between ecosystem services would also, almost by definition, occur than in the municipal-level clusters. Ideally, as a next step, one could overlay this ecosystem services map with predicted future land-use changes and forest threats and vulnerabilities, including predicted impacts of climate change, which would integrate the static service mapping exercise into a dynamic planning perspective.
Another additional perspective could be to explore some of the potential disservices from forests (that are not well-covered in the ecosystem services concept adopted by the Millennium Ecosystem Assessment) – notably the dangers of Mediterranean forest fires posed by an increasingly contiguous and homogenous forest-cover on abandoned agricultural lands, together with higher biomass densities in widely unmanaged forestlands.
Conversely, however, one could also speculate on how much extra ecosystem services these newly created forestlands have triggered, compared to a couple of decades ago when Catalonia had significantly less forests: at the extreme, is it just carbon being accumulated till the next big fire sweeps the landscape, or have there been tangible broader societal benefits to these expanding ‘new forests’?
On aggregate, ecosystem service maps like the ones developed in this study have many potential uses, for analysts and planners alike. Yet, they can also help us ‘putting ecosystem services on the map’ — in the more figural sense: decision-makers are being provided with tangible spatial tools to consider the synergies and trade-offs of managing our forests.
For more information, please contact José (Pipo) Roces-Díaz at: email@example.com
José V. Roces-Díaz, Jordi Vayreda, Mireia Banqué-Casanovas, Martí Cusó, Marc Anton, José A. Bonet, Lluís Brotons, Miquel De Cáceres, Sergi Herrando, Juan Martínez de Aragón, Sergio de-Miguel, Jordi Martínez-Vilalta. 2018. Assessing the distribution of forest ecosystem services in a highly populated Mediterranean region, Ecological Indicators, Vol. 93, pp. 986-997, ISSN 1470-160X.