The Future of the Sierra Nevada

The future of the Sierra Nevada depends on the decisions made by humans, because a large portion  of the dramatic changes in the area in the last 200 years or so have all been the result of humans. While it is true that a large part of the Sierra Nevada has been turned into National Parks, such as the Sequoia, Kings Canyon , and Yosemite National Parks in 1890 there are still many human influences that have the potential to either damage or save this area. For instance the National Parks help protect and preserve the forests areas (by decreasing the traumatizing clear-cutting that used to occur), and yet air pollution from places like the California Central Valley are currently polluting and damaging these areas that society is attempting to reserve. Similarly the biotic integrity of watersheds in the Sierra Nevada are currently being polluted by some of the industries allowed to continue in these areas (such as agriculture, hydro-power, and mining).  While it is true that people have attempted to preserve the natural biodiversity of these areas with the increased landscaping and general exploration of nature means that a concerted effort has to be put forth in order to preserve the water ecosystems that exist currently. The Sierra Nevada contains a large amount of protected areas that have helped preserve the ecosystems there, however human civilization, while slowed, continues to deteriorate these areas, and without increased awareness and action there is little hope that the original ecosystems in Sierra Nevada will continue to disappear.

Image Source

Sources:

McKelvey, Kevin, and James Johnston. "Historical Perspectives on Forests of the Sierra Nevada and

the Transverse Ranges of Southern Califronia: Forest Conditions at the Turn of the Century." Trans.

Array USDA Forest Service Gen. Tech. Rep. PSW-GTR-133. 1992. 225-246. Print.

Source one 

Peter B. Moyle and Paul J. Randall, Evaluating the Biotic Integrity of Watersheds in the Sierra Nevada, California. Wiley for Society for Conservation Biology. Conservation Biology, Vol. 12, No. 6 (Dec., 1998), pp. 1318-1326.
Source two

Ricardo Cisneros, Andrzej Bytnerowicz, Donald Schweizer, Sharon Zhong, Samuel Traina, Deborah H. Bennett, Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California, Environmental Pollution, Volume 158, Issue 10, October 2010, Pages 3261-3271, ISSN 0269-7491, http://dx.doi.org/10.1016/j.envpol.2010.07.025.
(http://www.sciencedirect.com/science/article/pii/S0269749110003179)
Source three