Breath of Clarity

Ecology Discussion #5: A

It is interesting to investigate not just human activity on ecosystem function, but rather focus on the reasoning behind the impact being disproportionate compared to past times. Human-induced environmental change is partly due to innumerable abuse of resources and damaging pollution which causes imbalance to the ecosystem’s otherwise less significantly disturbed function (BBC 2013). The disproportionate impact is due to the fact human urban population is increasing. A larger population entails a greater consumption of resources. Further, waste accumulates into an increasingly bigger piles, and the entire ecosystem pays the price.

In his essay, “Cheat Takes Over,” Leopold emphasized non-native species, as he phrases it as un-invited ecological guests, is unavoidable in terms of every region and resource. Although ecological stowaways started settling in new places early on, their spread is the difference maker as it is often so rapid and dominating relative to the customary progression of the pre-arrival space. Leopold provides the example of the invasion of the intermountain and northwestern foothills by cheat grass. Leopold described the taking over of cheat grass was caused by overgrazing. Then, as cheat grass spread to cover the raw earth, the fact it grows in dense stands with prickly was rendered the mature plant inedible to stock. Therefore, there was nothing to control its spread and its inflammable feature brought burning to the remnants of good browse plants in the face of a fire. Consequentially, the deer and elk depending on the latter sagebrush and bitter brush were left to eat the vastly shrinking supply of edible clumps. Leopold goes onto explain the range of impacts emergence of the cheat grass had on various areas and other animals. Still, the theme was the impact increased with the time for cheat grass to multiply.

While Leopold’s Odyssey exhibited an ecosystem’s resiliency by conveying the cycle of life, death and rebirth enabled by decomposition and growth, further, ecosystems are constantly heal itself and adapt. In the process of human-induced environmental change, resources deplete. That said, those who both depend on and fail to conserve the resources are at risk. As human impacts on the environment are intensifying, it raises vexing questions of how best to allocate the limited resources available for biodiversity conservation (Balvanera et al. 2001). With continued human-induced impacts depleting the resources the human species needs to survive, there is going to be a point where the human species will die. There will be new animals evolved from the altered set of conditions, and the ecosystem will continue to flourish in accordance with its new community. Therefore, ecosystem resilience enables sustainability to happen despite temporary destruction at the initial stage of ecosystem succession. Although human-induced environmental change makes it so an ecosystem cannot remain at the state it originally was at, the ecosystem’s resiliency leads to its rebuilding and continuous sustainability.


BBC. 2013. “Planet Earth: The Effects of Humankind”. Accessed Feb 3, 2020

Balvanera, Patricia, Gretchen C. Daily, Paul R. Ehrlich, Taylor H. Ricketts, SallieAnne Bailey, Salit Kark, Claire Kremen, and Henrique Pereira. 2001. “Conserving Biodiversity and Ecosystem Services.” Science, New Series 291: 2047.

Leopold, Aldo. 2013 Sand County Almanac & Other Writings on Conservation and Ecology. London: Penguin.

Comment by Jenny Murphy:


This was really well said. I think I had a more difficult time expressing what the professor was going for with the post this week. Your point about the earth potentially being unlivable for humans, but it will continue on and become livable for other organisms and eventually evolve to include more and more species is what the professor may have been looking for. When I was reading your post, it made me think of the extinction of the dinosaurs. Although that was most likely caused by a natural disaster and not over-use of resources, it basically is the same situation you discussed. The dinosaurs died off, the remaining living organisms eventually flourished, evolved, and the world, I am sure, was much different 2000 years ago than it was immediately after the extinction due to the resiliency of ecosystems.

My Reply:

Hi Jenny,

The idea about human activity’s contribution to environmental degradation hurting its own species is particularly useful in terms of explaining climate change to people. I am interested in investigating whether there is a misconception about the definition of climate change. Maybe people would care more about it if they understood it in terms of the human race’s health instead of simply contamination. I wonder how it would impact people’s effort to create environmental policy with stronger standards. Great point in saying biodiversity loss of one species impacts the ecosystem’s remainder. It changes the entire food chain and allows certain adaptive animals to flourish that would not have before the extinction. I wonder how salmon extinction would impact the food chain underwater in rivers and which animals would thrive as a result.

Comment by Professor Fenton Kay:

Very good post, Mary. It’s interesting that the cheatgrass problem remains with us today. Mature cheat, as you state, is virtually inedible by livestock. However, the new green shoots are eaten by cattle. The livestock industry in parts of the Great Basin has tried to make that latter fact belittle the negative impacts of cheat. On the plus side, cheat comes from the same area as chukar partridge and may be one reason why that introduced game bird is so successful in the Great Basin. Chukar consume cheat seeds and seedlings, but not enough to remedy the fire problem. What sort of program or method do you think might get a handle on cheatgrass?



My Response:

Hi Fenton,

It is interesting to consider the cheatgrass problem in the context of today’s conditions. In addition to cows, I would implement a method with the consideration that sheep and goats also eat cheatgrass (ATTRA Sustainable Agriculture 2020). Areas with cheatgrass can be used for a place to store cows, sheep and goats. People can use cheatgrass-filled sectors for providing free-range animal living. At the same time, I would only implement that method in areas without the chukar partridge. I could also supplement the first method with the strategy of pouring another of the chukar partridge’s resource into the area.


ATTRA Sustainable Agriculture. 2020. “What’s the best way to control cheatgrass in my pasture, using goats or flame weeding?”. National Center for Appropriate Technology. Accessed October 15.