How to make landscapes more sustainable: ASU ecologist focuses on big and small picture

A picture of a crying child with a boot pressed against his face is frightening. But zoom out and see that the child is holding the boot to his own face, and you get an entirely different perception altogether.

That viral meme proves the importance of context.

Arizona State University School of Life Sciences Dean’s Distinguished Professor Jianguo Wu wants landscape and urban ecologists to recognize that when designing ecological studies that look at land use. His lab has published four studies this year to illustrate just that.

“Sustainability science has to be done on multiple scales," Wu said. "Global scale is important. Local scale is important. Regional scale in the middle is very important and operational. From a distance, we see the big picture, but if you see the forest without seeing the trees, we can never see why. Mechanisms, processes — these are important. We need to zoom in and zoom out. See the context. See the details.”

In a paper published in the Journal of Land Use Science in April, Wu argues that the regional scale is the important missing link in this process. He said that scientists can understand similarities between regions by identifying both ecological patterns at global scales and information gleaned from local studies.

“If you work only on local ecosystems, they’re too small. You can’t incorporate all the socioeconomical processes and decision-making. The impact will be minimal,” Wu said. “But if you can institute it at a global level, we can improve our landscapes where we live, work and play. But we need to have concrete systems to work with. That’s where the regional scale comes in.”

However, finding solutions that work at multiple scales isn’t always easy to accomplish. A paper published in Landscape Ecology in February with Amy Frazier, assistant professor in the School of Geographical Sciences and Urban Planning, argues that discovering these solutions will involve linking landscape sustainability and landscape ecology. To understand how to sustain a landscape, scientists first must understand how all of its elements (plants, animals, humans) fit together to function.

As a researcher, Wu has focused on landscape ecology for 25 years, but when ASU started the Global Institute for Sustainability, he saw a natural connection. The institute brings together scientists from the natural sciences, ecology, geography, social sciences and design planning to form interdisciplinary collaborations.

This was a natural fit for Wu, who is interested in tackling landscape ecology problems from all angles. As humans continue to modify landscapes and reduce biodiversity, it is becoming more crucial for scientists to understand how to make landscapes more sustainable.

In a paper published in September by Landscape and Urban Planning, Wu and School of Sustainability graduate student Bing-Bing Zhou suggest that the way to do this is to focus on a diagnostic approach. This involves finding a problem and talking to people affected by that problem to understand what stands in the way of solving it.

“For example, for my dissertation, I am working on farmland preservation,” Zhou said. “What we’ve found is though we know where the best quality farmland is, the farmers don’t want to farm anymore. So those farmlands were just left abandoned. That’s what we call problem-driven and solution-oriented. The output of my research will be the social ecological solutions we can take to preserve the original farmland resources.”

Finding ways to solve landscape sustainability problems also becomes critical in urban areas, a direction Wu has noticed his students steering him toward in the last decade.

“I’m very much interested in urbanization. It’s a global phenomenon,” Wu said. “The whole world has become, and will continue to become, more urban. So urbanization is definitely a very important issue in sustainability and ecological research. Cities have to be better studied and better planned.”

For example, Wu pointed out, Chile is 100% urbanized now. No one resides in its rural areas. Thus, they need to find a way to preserve natural landscapes while urban areas continue to grow.

Wu’s former graduate student Ignacio Fernandez, now an assistant professor at Universidad Mayor in Santiago, Chile, is trying to do just that.

However, he’s taking a unique approach.

While most studies focus on the patches of natural land found in urban areas, in a paper published in July by Landscape and Urban Planning, Fernandez and Wu focus on the context. In this case, the context is the urban areas that surround the natural patches.

Outwardly, cities may seem very similar. However, if you drive around them, they can change very quickly from all-concrete business developments to suburban neighborhoods filled with yards to large golf courses and universities with vast swaths of green space.

In their paper, they found that which type of area surrounds the natural patches (referred to as the urban matrix) has an effect on its biodiversity and productivity.

“One of the major suggestions that we make in this paper is that the future of urban planning needs modeling focused on the natural areas, but also the context that will support those areas,” Wu said. “The matrix could help biodiversity conservation, but at the same time, it can harm. If there are a bunch of reserves surrounded by urban land use with concrete and impervious surfaces, it will create edge effects that negatively impact the patches. Instead, if we have a golf course or agricultural field, those negative effects will be reduced.”