BONN, Germany (Landscape News) — In an era of increasing competition for resources, with pressing needs both to nourish human populations and support ecosystems and biodiversity, the search for holistic solutions that minimize conflicts over land use is a hot topic for ecology and landscape management.
Traditionally, ecology has focused on studying individual functions within ecosystems and consideration of how they relate to their drivers. But ecosystem functioning is actually “inherently multidimensional,” say the authors of a new study published in Nature, Ecology and Evolution.
In recognition, the term “multifunctionality” has grown in popularity in recent years. It is usually referred to broadly as the ability of an ecosystem to deliver a number of different functions or services simultaneously.
As lead author Peter Manning explains, if we can take better measures of the multitude of interlocking things that ecosystems are providing, it can help us to make much more careful decisions about the ways we manage and interact with them.
In fact, multifunctionality is named as one of the “Ten principles for a landscape approach” to reconciling agriculture, conservation and other competing land uses, in a key document by experts in the ecology and landscape management fields.
However, to date the concept has not been well-defined or -measured, which has limited its accuracy and usefulness, Manning said.
But it seems that, just like use of the term “landscapes” to address multiple stakeholder needs and activities in a given area, “multifunctionality” also has people scratching their heads.
ECOSYSTEMS AT YOUR SERVICE?
Manning, an ecologist at the Senckenberg Biodiversity and Climate Research Centre in Germany, has a fair notion of where all this bewilderment comes from.
His own background is in biodiversity and ecosystem-functioning research. Within that area, multifunctionality has usually been explored in terms of how the biodiversity of an ecosystem affects its ability to perform multiple functions, like cycling soil nutrients or pollination.
However, at the same time, multifunctionality research has also been occurring within landscape management fields, where it is used to assess an ecosystem’s ability to provide a range of services to humans. And therein lies the confusion, Manning said. The term has been used both to look at ecosystem functioning in and of itself, and to consider the values of these functions from a human perspective.
“So we’re really talking about two different things,” he said, “and a lot of past research has mixed the two together.”
Accordingly, the paper makes a clear distinction between what it terms “ecosystem-function multifunctionality” (assessing ecosystem functions), and “ecosystem-service multifunctionality” (assessing ecosystem services to humans). Having cleared that up, the paper then offers new ways of measuring the extent to which a particular ecosystem is “multifunctional.”
“Till now, there hasn’t really been a good way of quantifying ecosystem-service multifunctionality, especially at larger scales,” Manning said. “There’s a lot of cases where people look at trade-offs and synergies, and talk about these things, but often the numbers aren’t there. So there’s a real need to toughen up this kind of science.”
The study puts forward a new tool to help with this task. “You can test out how different management options would change the overall benefit of the ecosystem to different groups of people,” he explains.
The tool also allows users to quantitatively weight the desires of different groups of people using the landscape.
“Say we’ve got farmers and the ecotourism industry in the same region,” Manning said. “We could give them an equal weighting for what they want, and then work out what the management options are. So it gives you a quantitative way of supporting decisions on how landscapes should be managed for the ecosystem service requirements of multiple groups.”
CHALLENGES AND POSSIBILITIES: SCALING UP
As is often the case in data analyses, the proposed metrics simplify reality, and risk missing out on important factors. The approach is also quite data-intensive, and some of the elements, such as people’s requirements and demands for land use, can be difficult to measure and represent quantitatively.
“There’s also a difficulty in terms of taking measures of ecosystem function from small-scale plots and upscaling those to the (larger) landscape level,” Manning adds. Methods such as remote sensing hold possibilities, though there are question marks as to how accurately these measures reflect realities on the ground.
“I think the method is feasible, and it’s just about reducing the uncertainty in the estimates we get,” he says. “And where there is uncertainty, we need to make sure we communicate that properly, so that people understand that this isn’t black and white, right or wrong, but it’s the best estimate we can make.”
The research team is now applying the framework to a number of studies. One such project is within the Biodiversity Exploratories, which looks at the relationship between land biodiversity and ecosystem functions and services in German forests and grasslands.
Manning’s team is using the new method to predict ecosystem functions at the plot level and then upscale those measures for landscapes. They’re also talking to stakeholders and finding out their preferences and priorities in order to provide the weightings for the ecosystem-service multifunctionality measures that result.
“We think it’s a general theory which can be applied to quite a wide range of different ecosystems and landscape management cases,” says Manning. “I’m sure we’ll find along the way that there are things we need to tweak for particular cases, but we’re looking forward to seeing how it works in practice.”