“Ecosystem” is not a word that comes readily to mind when contemplating a garbage dump. Even people who embrace so-called novel ecosystems are usually referring to interesting new jumbles of plants and animals, not giant piles of trash. Yet perhaps we might put aside our preconceptions and view dumps through an ecological lens: as concentrated sources of energy — and also risk — intertwined with a great many nonhuman lives.
In a review published in Global Ecology and Conservation, biologists Pablo Plaza and Sergio Lambertucci of Argentina’s National University of Comahue argue that garbage dumps deserve more careful attention. Found wherever humans are, they’re a significant landscape-scale feature; they’re indeed novel ecosystems, featuring new combinations and abundances of species, and also novel is their steady, year-round provisioning in landscapes where resources otherwise fluctuate with the seasons.
“Rubbish dumps produce impacts both positive and negative,” said Plaza and Lambertucci in an email. Many animals, including some threatened or endangered species species — among them crowed cranes, California condors and Malayan sun bears — regularly consume what we throw away. (Indeed, the largest concentrations anywhere of endangered Egyptian vultures are found in the dumps of Socotra, Yemen.) “Food availability from rubbish dumps enhances population abundance, especially in birds but also in mammals and reptiles,” write the researchers.
Yet garbage dumps can be sources of toxins, too, turning into “ecological traps” that attract individual animals but cause long-term harm to populations. They can favor the spread of disease and the establishment of invasive species. And apart from these species-specific consequences, the larger effects of garbage dumps on predator-prey relationships, migration patterns and regional ecological dynamics are largely unknown.
These are important issues to study, say Plaza and Lambertucci. A better understanding of garbage dump ecology might help people manage them better. A case in point: garbage dump closures, which could have unforeseen cascading impacts. “It is important to take into account the potential impact on the species that use them,” wrote Plaza and Lambertucci in an email, “and also the potential impact that species exploiting organic waste can produce on other species.”
Which isn’t a reason not to close dumps — or, for that matter, not to reduce food waste. Rather, closures could happen gradually, or attention be paid to minimizing harms where food waste remains available. Garbage dumps might simply be managed more thoughtfully, with an appreciation of their place in a larger community of life. In the Anthropocene, everything is an ecosystem.
Source: Plaza, Pablo and Lambertucci, Sergio. “How are garbage dumps impacting vertebrate demography, health, and conservation?” Global Ecology and Conservation, 2017.
Image: Yathin / Flickr
