Ecosystem Crises Interactions. Merrill Singer

Ecosystem Crises Interactions - Merrill Singer


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from cutting it down, slicing it into boards, and shipping it overseas to build structures in a wealthy country. Nor will it change the fact that the loss of such spirits/trees fuels climate change, which is now causing droughts and killing large stretches of rainforest. Moreover, are we to accept as a credible reality the statement by Donald Trump—one echoed by many like‐minded politicians and conservative think tank writers and spokespersons who are members of the tribe of climate change deniers—that “Global warming is a total, and very expensive, hoax!” (quoted in Schulman 2017)? While advocates of the ontological turn are correct in demanding that we be mindful in writing about the realities of other peoples as well as the limits of all truth claims, there are severe costs to not striving for an objective understanding of the environment.

      As noted, the modern science of ecology is one of the key fields concerned with developing an objective understanding of the complex interconnections that make up the environment. Of no less interest are the limits of interconnection. As the urban ecologist Liam Heneghan (2015), using the classic “butterfly effect” illustration of connectedness, states: “if the dominoes line‐up and the circumstances are just so, a butterfly’s wing beat over the Pacific may hurl a typhoon against its shores, but more often than not such lepidopterous catastrophes do not come to pass.” Still, a lesson of ecology is that small changes in initial conditions can, at a certain point, lead to drastic outcomes—an issue taken up in Chapter 10.

Photograph of Charles Darwin.

      Source: National Portrait Gallery.

      2.3.1 Ecosystems

Photo depicts tide pool.

      Source: rreeths/Pixabay.

      The term “ecosystem” is used specifically to refer to a community of directly interacting living organisms and nonliving elements such as air, water, rocks, and soil. In an ecosystem, interactions occur among organisms (across all phyla) and between organisms and other environment components. Central to the relationships among these ecosystem components is the flow of matter and energy. A food chain, for example, involves the flow of matter and energy from autotrophs (e.g., plants) to heterotrophs (e.g., herbivores and carnivores) and, eventually, to decomposers—a flow that occurs in all ecosystems.

      2.3.1.1 Ecosystem synergy

      Freshwater is ever‐present in the SLM because of its location near the outlet of a river basin, low‐lying topography, permeable peat soils, underlying aquafer, and rainfall. The resulting wet environment “supports bird [and other animal] life that maintains biological diversity, attracts tourists, protects archaeological artefacts and reduces CO2 emissions; raising water levels to or above the ground leads to net greenhouse gas uptake by the wetland” (Acreman et al. 2011, p. 1543). In light of climate change, it is notable that peat is the largest and most efficient terrestrial store of CO2. On average, peat wetlands sequester 10 times more CO2 per acre than any other ecosystem. When peat is mined, however, it is exposed to air. Carbon contained within it (from decomposed biota) combines with oxygen in the air to produce CO2, which is emitted into the atmosphere (Dunn & Freeman 2011). In this way, peatlands can be transformed by human actions from a CO2 sink (or storage site) to a CO2 source; that is, from a resource that restricts global warming to a source that drives it.

      Another


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