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Getting The Most Out Of A Jigsaw Ecosystem

Posted on January 27, 2022 by Sam Perrin Leave a comment

Image Credit: Mainaksinghabarma, CC BY-SA 4.0, Image Cropped

Increasing cover of natural areas at smaller scales can improve the provision of biodiversity and ecosystem services in agroecological mosaic landscapes (2022) Rosenfield et al., Journal of Environmental Management, https://doi.org/10.1016/j.jenvman.2021.114248

The Crux

While nature documentaries insist on portraying the natural world as entirely separate from human life, the fact is that ‘natural’ areas exist side by side with, and often within a mosaic of, human and semi-human (think agricultural or grazed) ecosystems. These natural ecosystems provide a wide array of services – they hold biodiversity, suck carbon in from the atmosphere, maintain clean water, and even regulate local temperatures.

With a growing global population, maintaining these ecosystems unfortunately isn’t as simple as leaving the natural world alone. Development needs to be planned with these ecosystems in mind, and choosing exactly where to leave them intact is tricky. Scale is a big problem here – does leaving one big patch of forest untouched give the same benefits as leaving many smaller patches dotted throughout a landscape? That’s what today’s researchers were trying to answer.

What They Did

Today’s researchers studied a large region in south-west Ontario, Canada. The region contained a number of different ecosystems, which they broke into natural, agricultural, and urban areas. They selected regions across the different areas to test for different indicators of ecosystem services:

Biodiversity – in this case the abundance and species richness of different plant species
Carbon storage – in this case measured by the mass of trees above ground throughout the regions
Local climate regulation – the ability of an ecosystem to regulate local temperatures
Water quality – checking the concentration of different minerals in local water sources

They then compared these to the percentage of these regions which were covered by natural, agricultural, or urban areas.

Did You Know: Cultural Landscapes

Large agricultural clearance often creates fragmented landscapes and damages population which depends on large, connected landscapes. Yet at a small scale, very localised grazing often create small patches that break up the usual landscape and can sometimes increase species richness on a larger scale. It’s a phenomenon that has often led the idea of ‘cultural landscapes’ being deemed necessary for a healthy landscape. Yet often these landscapes are a fairly recent phenomenon, and not really representative of the ‘natural state’ of an ecosystem. Furthermore, they may increase species richness on a small scale, but if they expand too much those effects start to be outweighed by their fragmenting effects.

What They Found

The most notable patterns came with an increase in natural land cover. Where there were higher proportion of natural land, biodiversity increased and local temperature decreased at all spatial scales. Aboveground carbon and water quality also increased with increasing natural land, though only at smaller scales.

Increasing urban land area led to lower biodiversity and higher temperatures across all scales, while the only pronounced effect an increase in agricultural land had was to decrease local temperatures.

Problems

Obviously a high level of plant species richness does not necessarily translate to high species richness of other organisms like fungi and animals. Species richness itself can be misleading, as high abundances of one particular species and small abundances of others will give the same value as a more even spread across the region. However, a more intensive survey would have increased the workload tenfold, and I understand why the authors went for plant diversity, which generally can be a good indicator for more comprehensive estimates.

So What

While there are many who argue for the positive influence of agricultural areas on the environment, this study suggests that natural ecosystems are by far the most important contributors to important ecosystem services. The fact that this was even more pronounced on smaller spatial scales means that a mosaic-like spread of natural areas throughout a landscape is beneficial, rather than isolated patches of forest dotted throughout larger areas.

These are important notes for environmental planners, who need to be considering exactly where agricultural areas (and further urban encroachment) should lie in the future. Ecosystems provide us with a host of tangible benefits, and we need to preserve these, not to mention the bevy of species that exist within them.

Dr. Sam Perrin is a freshwater ecologist who completed his PhD at the Norwegian University of Science and Technology and will quite happily go for long walks in the forest in order to skip work and say he “got lost”. You can read more about his research and the rest of the Ecology for the Masses writers here, see more of his work at Ecology for the Masses here, or follow him on Twitter here.

Paper of the Week

Divided and Conquered

Posted on September 8, 2021 by Adam Hasik Leave a comment

Image credit: Alex Proimos, CC BY-NC 2.0, Image Cropped

Experimental habitat fragmentation disrupts nematode infections in Australian skinks (2019), Resasco et al., Ecology. https://doi.org/10.1002/ecy.2547

The Crux

Habitat destruction is an all-too-familiar side effect of human development and expansion. But another prevalent issue is habitat fragmentation, whereby habitat isn’t completely destroyed, but instead broken up into fragments and separated by developed areas. While some may think this is good, because there is still habitat available for wildlife to inhabit, the disconnected nature of what is left makes it very difficult for most wildlife to thrive, as they require much more connected landscapes.

Though fragmentation has been well studied in the past, less is known about how it affects parasites. Because they depend on other organisms for their own survival, parasites in particular are at risk of local or even extinction due to the cascading effects of species loss (i.e., coextinction, see Did You Know?). The complex nature of many parasite life cycles, in addition to a scarcity of experimental studies, makes it difficult to predict what effects that fragmentation will have on parasites. Today’s authors used a long-running, large-scale fragmentation experiment (The Wog Wog Habitat Fragmentation Experiment) to determine how fragmentation affects host-parasite interactions.

Paper of the Week

How You Can Help Ancient Ungulate Conservation Using Ancient DNA

Posted on February 4, 2021 by Sabhrina Gita Aninta One comment

We write so much here on Ecology for the Masses about the danger that countless species face in today’s world. So every now and then we need to give tangible solutions and talk about how to actually save an endangered species. It’s not an easy task, and every one comes at it from a different angle. But right now, I want to talk about the fate of two amazing species, the work my colleagues and I have been doing to try and save them using DNA from museum collections, and how you can help. Yes, you. Our awesome readers. Here is a story about my research.

Opinions

The Varying Roles of Indigenous, Government, and Private Protected Areas in Conservation

Posted on June 17, 2020 by Sam Perrin Leave a comment

The Gawler Ranges, an area of Indigenous protected land in South Australia (Image Credit: Korkut Tas, CC BY-SA 3.0, Image Cropped)

The Crux

The designation of Protected Areas (PAs) has been a key tool in the fight to retain biodiversity and restore ecosystems globally. Designating a region as protected goes a long way to ensuring the survival of a wide rage of species, both locally and on much larger scales. In recent decades, private PAs have been growing in number, and on top of that, 7.8 million squared kilometres worldwide are now registered as Indigenous PAs. As a result, conservation goals are often formed with all three types of protected area in mind.

There has been ample research showing that all three types of PA have been effective in conserving wildlife and habitat types. But all three have different characteristics, both in governance and allocation. Today’s authors wanted to find out whether they protected different types of habitat, and what that could mean for conservation policy going forward.

Paper of the Week

Bigger is Not Always Better in Habitat Conservation

Posted on February 21, 2020 by Sam Perrin 2 comments

Whilst Island Biogeography Theory originally led many to believe that larger, more connected patches of habitat are more important for species conservation, new research suggests that overlooking smaller patches could be dangerous (Image Credit: LuxTonnerre, CC BY 2.0, Image Cropped)

Global synthesis of conservation studies reveals the importance of small habitat patches for biodiversity (2019) Wintle et al., PNAS, https://doi.org/10.1073/pnas.1813051115

The Crux

Human land use over the past millenia has divided species habitats into smaller and smaller patches – a practice which often leaves conservationists with the tough choice of which remaining patches they should focus their efforts on. Traditional practice has seen the prioritisation of large patches that are well connected to other, with this preference often meaning that smaller more isolated patches are neglected, and often cleared.

This week’s paper authors wanted to check whether this was really the best way of doing things, by looking at the relative conservation value of a variety of habitat patches.

Paper of the Week

The Unseen Effects of Habitat Loss

Posted on January 27, 2020 by Marina Schmoeller Leave a comment

Whilst climate change continues to hog the limelight, habitat loss remains the key threat to biodiversity worldwide. And whilst events like the Australian bushfires obviously contribute to habitat loss, its main cause is land clearing, whether for agriculture, cattle grazing, mining or urbanization. No matter how many politicians deny or try to deviate attention from it, scientists have shown time and time again just how threatening habitat loss is to our planet’s biodiversity.

On the surface, the process seems quite simple. Habitat goes away, animals lose shelter and food. Yet this is just the tip of the iceberg. Many processes take place below the surface, cascading through an ecosystem. So let’s have a look at the manifold effects of habitat loss, and why it’s the greatest threat to biodiversity today.

Opinions

The Vital Role of Indigenous Peoples in Forest Conservation

Posted on January 22, 2020 by Sam Perrin Leave a comment

The Amazon rainforest, which houses the largest area of intact forest landscape which lies within indigenous lands (Image Credit: David Evers, CC BY 2.0, Image Cropped)

Importance of Indigenous Peoples’ lands for the conservation of Intact Forest Landscapes (2020) Fa et al., Frontiers in Ecology and the Environment, https://doi.org/10.1002/fee.2148

The Crux

Pristine forests remain not only a home for a huge range of biodiversity, they are also important resources for carbon storage, meaning their protection will become crucial as temperatures rise globally. Yet the term ‘pristine forest’ can be subjective. With this in mind, Peter Popatov et al., defined an IFL (Intact Forest Landscape) as a seamless mosaic of forest and associated treeless ecosystems that do not display obvious human activity or fragmentation. These areas are capable of housing entire species, including those that have expansive ranges.

The intent of this paper was to try and determine what proportion of that land intersects with land owned by Indigenous Peoples, to see how significant a role Indigenous Peoples could play in both conservation of biodiversity and the mitigation of climate change.

Paper of the Week

Killing 2 Million Cats: When Broad Targets Aren’t Enough

Posted on August 7, 2019 by Sam Perrin Leave a comment

Image Credit: Joey Doll, CC BY 2.0, Image Cropped

Conservation or politics? Australia’s target to kill 2 million cats (2019) Doherty et al., Conservation Letters, https://doi.org/10.1111/conl.12633

The Crux

We’ve talked a lot lately about competition between causes on Ecology for the Masses. Often when extra attention is given to one cause over another equally valid cause, it’s a product of social trends coinciding at the right time, sudden events capturing the public interest (think the Notre Dame fire) or a particularly effective marketing campaign. But sometimes a cause or a conservation target can be used to deliberately distract the public from another cause, and it’s a potential example of this that we’re looking at today.

Australia has long had an issue with cats. They’ve decimated populations of native species, playing a large hand in the extinction of many species found nowhere else. So it makes sense that part of Australia’s first Threatened Species Strategy would be to minimise the impact of cat populations on local wildlife. The strategy included a target of 2 million cats being killed between 2015 and 2020. Whilst this might sound like a reasonable goal, this paper argues that the actual scientific evidence supporting the target is pretty weak, and goes into some alternatives and motives.

Paper of the Week

Biodiverse Gardens: Where Doing Less is More

Posted on June 27, 2019 by tanjakp Leave a comment

Kiftsgate Court Garden: The Wild Garden 1. An example of a “wild garden” in the UK, where the plants have been left to grow (Image Credit: Michael Garlick, CC BY-SA 2.0, Image Cropped)