Ecology

Ecology is the study of environmental systems, or as it is sometimes called, the economy of nature. "Environmental" usually means relating to the natural, versus human-made world; the "systems" means that ecology is, by its very nature, not interested in just the components of nature individually but especially in how the parts interact. Ecology is technically an academic discipline, such as mathematics or physics, although in public or media use, it is often used to connote some sort of normative or evaluative issue as in something is “ecologically bad” or is or is not “good for the ecology”. More properly ecology is used only in the sense that it is an academic discipline, no more evaluative than mathematics or physics. When a normative or evaluative term is needed then it is more proper to use the term “environmental”, i.e., environmental quality or “environmentally degrading”. Most professional ecologists are not terribly unhappy when ecology is used in the normative sense, preferring the wider public awareness of environmental issues today compared to the widespread ignorance of three decades ago. 

The subject matter of ecology is normally divided onto four broad categories: physiological ecology, having to do with the response of single species to environmental conditions such as temperature or light; population ecology, usually focusing on the abundance and distribution of individual species and the factors that cause such distribution; community ecology, having to do with the number of species found at given location and their interactions; and ecosystems ecology, having to do with the structure and function of the entire suite of microbes, plants, and animals, and their abiotic environment, and how the parts interact to generate the whole. This branch of ecology often focuses on the energy and nutrient flows of ecosystems, and when this approach is combined with computer analysis and simulation we often call it systems ecology. Evolutionary ecology, which may operate at any of these levels but most commonly at the physiological or population level, is a rich and dynamic area of ecology focusing on attempting to understand how natural selection developed the structure and function of the organisms and ecosystems at any of these levels. 

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According to estimates from the international research organization, Global Footprint Network, today marks that day of the year when human impact and demands on the planet begin to exceed what Earth can support.

Basically, we’ve already spent our environmental budget for 2011. Imagine not eating for the next three months. Not consuming, or producing, or throwing anything away. The entire human race and all our systems are in a state of suspended animation from now until the end of the year. That’s how far from sustainable our demands and impact on the planet have become.

Since sometime in the 1970s, when world population was about 3.7 billion the planet hasn’t been keeping up with the demands we’ve placed upon it — a condition known as ecological overshoot. Yet, according to UN estimates, world population will reach 7 billion next month — nearly twice what it was when we first crossed into unsustainability.

Of course, population is but one factor in ecological overshoot. In the near term, the emerging economies of the developing world will stress the planet far in excess of what population growth alone would suggest.

Global Footprint Network calculates that it would now take between 1.2 and 1.5 Earths to sustainably support our current ecological demands. Before mid-century, we’re likely to require the resources and regenerative capacity of two Earths.

Critics may claim that it’s impossible to calculate with any accuracy the ability of the Earth to support human needs, just as it’s impossible to arrive at an accurate count of world population. While true, such thinking misses the point.

Whether the day of environmental overshoot is today, last month, or next month, evidence that we are well past the threshold of sustainability is everywhere, from rising food and energy prices, to depleted aquifers, disappearing species and increasing atmospheric carbon.

One way or another, our unsustainable practices will eventually be brought into balance. The only question is: what will be the conditions of Earth and the human race when that happens.