Pre-eminent biologist and ecologist EO Wilson is credited for championing the proposition of a half-earth (1); dedicating 50% of the planet toward conservation of life, the preservation of ecosystems, habitat conservation, and buffering of CO2 emissions. This is simply to scratch the surface, and potential benefits might be considered from any number of environmental, health, economic, and social capital perspectives. The preservation of biodiversity and functional nature reserves is predicated on connected and confluent wilderness areas that incorporate and connect entire ecosystems, in the form of wildlife corridors or otherwise (2,3); in any case reaching beyond simply the presence of isolated parks, sporadic urban green spaces, and nature strips. These large-scale biological ecosystems required to harbour biodiverse life can be considered as representing complex systems (4), demonstrating complex, dynamic interactions present on multiple levels, and complex systems phenomenon – feedback, nonlinearity, emergence (5,12). More imaginative conceptualisations proposed by such polymaths as James Lovelock include the Gaia hypothesis (6), which deals with the entire earth as a homeostatic entity and active adaptive control system that demonstrates properties not predictable from the sum of its parts (6), essentially describing characteristics akin to emergence (12). The relevance of this model is such that loss of particular predator species in a food web can lead to monopolisation of important, limiting resources such that ecosystems lose diversity (7). On the same wavelength, Levin (5) describes the existence of keystone functional groups, comprised of a small set of species upon which critical ecosystem processes rely. In these complex biological systems, the loss of one species can spiral in unpredictable and devastating ways to the ultimate demise of entire ecosystems. And the mechanistic basis for this is intuitive enough to model, such that in any kind of food web, loss of critical species can lead to cascading secondary extinctions with great consequence (8). Like many, I express much scepticism for the biological utility of the scant and detached manmade parks, green areas, and nature strips – fundamentally disparate from nature, paralleling the simplified and exogenously imposed structures as seen in agriculture and forestry. Such natural artifice has been rebuked by Levin and others for their non-functionality, aberrance, and fundamental lack of heterogeneity, considered essential to ecological adaptation (5). If current patterns are to continue, of seemingly boundless destruction of native forests (9) and feeble non-attempts at preserving green spaces in and around cities (10), biodiversity losses will be inordinate (13). And above this dizzying issue of wilderness loss in absolute numbers, it is the patterns of loss and patterns of protection that become important. In this complex biological system, a critical but underappreciated feature of ecosystem health is ecological interactions, the loss of which can precede species loss (11). Described by Valiente-Banuet and colleagues, environmental destruction and fragmentation means species are reduced to such scattered low-density populations that these crucial ecological interactions are lost, ultimately leading to species extinction and ecosystem decay (11). Thus the functionality and health of ecosystems is dependent on both their components and interactions.
Shunning the silent, ever-pervasive pre-ecological collapse nihilism, and the trappings of judicious commentary without concurrent action, a model for the task may be two-fold: including preservation of existing ecosystems and natural landscapes, and the gradual restoration of existing environments to foster biodiversity. The approaches are complementary, and encouragingly, starting to take form in various models around the globe.
· Greening Australia (environment restoration) https://www.greeningaustralia.org.au
· Half-Earth Project (environment and biodiversity) https://www.half-earthproject.org
· Wyss Foundation (habitat protection) https://www.wyssfoundation.org
Additionally, the impacts of individual conservation efforts and crowdfunded projects is not to be discounted, with promising stories emerging from collaborative efforts to protect natural places.
· Crowdfunded land given to public (NZ) https://www.bbc.com/news/world-asia-36759321
T Michniewicz, August 2019
Reference
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