Tuesday, November 26, 2013

(source: http://upload.wikimedia.org/wikipedia/commons/1/1c/Sierra_Nevada_aerial.jpg)

The Geographic Scale

The Sierra Nevada Mountain range is definitely an ecosystem that is incredibly vast, and stretches out for more than 250 miles across the state of California. Realistically, this ecosystem has a regional scale, and is the most important source of water for all of California and its agriculture. Despite this however, there are very many National Parks and reserve areas that are protected federally or conserved locally, such as Yosemite National Park, the Sequoia National Forest, and Lake Tahoe.

(source: http://power.arc.losrios.edu/~reevesl/assignments/images/map_ca.jpg)

Brief History of the Sierra Nevada's


(source: http://upload.wikimedia.org/wikipedia/commons/2/23/Chinese_railroad_workers_sierra_nevada.jpg)
Seeing how this ecosystem is a mountain range, there is not a lot that humans can do to destroy it. The granite that these mountains were mainly formed from is an incredibly strong rock, that does not erode very easily. The early Native American and Spanish explorers of California had almost no impact on the ecosystem. These people lived off the land and had hunter and gatherer preferences or very small settlements that did not take away from the mountains. 

The first notable non-natural degradation of the land came from the Gold Rush that began in 1848. This Gold Rush caused people to begin dredging rivers and streams from the snow melt, blasting and digging out mines, and removing trees to make way for roads and settlements in the mountains. Historically, the gold rush was the catalyst for most of the damage that has occurred to this vast ecosystem across its lifetime, however the damage left was not very prominent across the range as a whole. This was due to the facts that with the mines and hunt for gold, a need for railroads and streets came into being. Roads were formed to connect mining towns to their mines and prospect sites, while railroads were used to connect these Northern settlements with the major cities like Sacramento and San Francisco. The building of these means of transportation involved the removal of trees, boring of tunnels, and carving and construction of flat land across the mountainsides. These railroad lines still exist today, albeit they have probably been restored and more modernized. Mining roads have also no doubt been paved over and put to a more modern use, for it was this California Gold Rush that truly brought larger amounts of settlers into these mountains.

Despite all this work however, historically speaking the human impact in this ecosystems has been quite low. Many of the special areas in this ecosystem were protected before major damage could befall them, and a large amount of the ecosystem is also protected under the Wilderness Act. Outside of the roads, ski resort cities, Gold Rush damage, and stream reinforcement efforts, this is an ecosystem that has been largely undisturbed by humans. because of this, I would have to say that historically the environmental impact has been good.


(source: http://www.usace.army.mil/About/History/HistoricalVignettes/CivilEngineering/081LoneliestRoad.aspx)

(source: http://tristanhowardproductions.com/Images/Sierra%20Nevada%20Mountains/Sierra%203136.jpg)

Human Impacts on the Sierra Nevada

Forests

One of the major human impacts that have affected the Sierra Nevada area is logging. The expanse of western civilization, was the reason for most of the heavy logging that drastically affected the area. Forest in the Sierra Nevada provided the lumber that humans required to expand cities. In fact, the Sacramento and San Joaquin Valleys were largely assisted in their foundation by the lumber obtained from this area. During this period lumber was used for transportation and growth of local markets. A great deal of the logging done was connected to the mining industry because timber was used to support the tunnels and prevent them from caving in.  Most common method of logging in this area for a long period of time was clear-cutting which is a highly destructive form of logging and heavily impacted the forests of this area. In fact, once humans finally realized the negative impact such unsustainable clear cutting of forest was having, there was a move to start preserving the rapidly disappearing forests in the area. In 1890  Sequoia, Kings Canyon, and Yosemite National Parks were founded. Since then there has been a drop in the destruction logging had on this environment, in fact the future of these protected areas is decidedly more positive now that clear cutting has dropped and regulations have been enforced.  In the last 90 years conifer forests have remained fairly consistent, and while there is no evidence that there is severe shrinking acreage, there have been no spreading acreage either.


This chart shows the increased area of protected forests in the Sierra Nevada.


The move from clear cutting to other means of logging, shows both the severity of the original impacts on forests and the move to preserve the present status of the protected forests in the Sierra Nevada, which attributes to the relative static status of the forests growth.





















Above are some of the impacts humans have had on the forests in Sierra Nevada which explain their current status of relative unchanging status despite efforts to increase protection for these areas.

Sources:
McKelvey, Kevin, and James Johnston. "Historical Perspectives on Forests of the Sierra Nevada and
the Transverse Ranges of Southern California: Forest Conditions at the Turn of the Century." Trans.
Array USDA Forest Service Gen. Tech. Rep. PSW-GTR-133. 1992. 225-246. Print.
Link

Water

Forests are not the only aspect of the Sierra Nevada that has been affected by humans, the aquatic ecosystems in this area have also suffered. Of the watersheds in the Sierra Nevada 58%  of the native aquatic biota are shown to be in poor or fair condition. Watersheds with particularly low scores are all located in the same areas that humans are using for agriculture, hydro-power, and hydraulic mining. While all these industries help provide the benefits of food and energy, needed for human civilization, the environmental impact, results in the deterioration of the regions watersheds, which then affect the animals in these habitats. In fact, many of the Sierra Nevada watersheds no longer have the native frogs and fish that used to originally populate them. The exploitation of logging, mining, trout stocking, and dam construction have all negatively impacted the water systems in the Sierra Nevada. The introduction of non native fish has also had a negative impact on the aquatic ecosystem. Actually, the three watersheds with the highest scores in relation to the W-IBI scores (Deer Creek, Mill Creek, Clavey River) all contain their native amphibian and fish and are in protected areas that allow for the continuation of a natural system that then preserves the water integrity for those areas.    


"This dichotomy is reflected in the results of the principal components analysis, which produced two factors with eigenvalues greater than 1.00 (Table 1). Factor 1, explaining 42% of the variance, had only a moderate negative loading on the W-IBI score but was strongly positively loaded on the two road variables and strongly negatively loaded on mean elevation and the percentage of the watershed that was historically fishless. In factor 2, explaining 17% of the variance, the W-IBI score had a high negative loading, whereas the percentage of hectares containing dams, reservoir capacity, and the percentage of the watershed that was historically fishless had high positive loading" (Direct Quote).

Sources:


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.
Link

Air

The air in the  Sierra Nevada has also been affected by human civilization. The main reason for this being the California Central Valley air pollution, which is transferred from its original sites and is shown to spread deep into the Sierra Nevada area which is then able to negatively damage the protected areas in the Sierra Nevada. Studies show that this air pollution is indeed created by humans because the nitric acid and NH3 concentration levels diminish the farther away from human civilization (California Central Valley) one gets. The increased concentration of NH3 and HNO3 in the Sierra Nevada raises the N deposition amounts in forests in these areas elevating past levels that foster nutrition. This then affects the potential growth of forests, water quality, and animals exposed to this increase in the air pollutants.  In this way, even the efforts to protect the forests and water systems in this area are hampered by civilizations toxic proximity to these areas.                                                                                                              
"Calculated maximum and minimum dry N deposition from HNO3 and NH3 decreased eastwards. Sites closest to the San Joaquin Valley had the highest levels of HNO3 and NH3 deposition, with much lower N deposition resulting from HNO3 than from NH3" (Direct Quote).

Sources:

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)
                                                             

Data Showing Current Impacts

Monitoring Location with Maximum 3-Month SUM W126 Greater Than or Equal to 7 ppm-hrs (2007)



The EPA recommends that the range should be established between 7-21 ppm hours, so that the W126 can be less than that. The W126 index is used as a metric to measure harm to vegetation due to ozone pollution.

Upon looking at this table, we see that the three national parks located in the Sierra Nevada (Sequoia and Kings Canyon - Ash Mountain & Lower Kaweah, and Yosemite) all surpass the upper range of 21 ozone ppm-hour. From this, we are able to see that such human impacts are quite apparent in the Sierra Nevada region, as the ozone levels at these locations are substantially high compared to the other national parks.

Ozone occurs when sunlight generates photochemical reactions which involve nitrogen oxides and volatile organic hydrocarbons VOC, and carbon monoxide, which usually are created from gas engines, automobiles, and fossil fuel use.

Ozone has a negative impact on plants as it can cause numerous symptoms to occur such as chlorosis and necrosis. It can also cause symptoms such as flecks, stipples bronzing and reddening. Essentially, ozone has a detrimental effect on plants.



Source: "Air Quality in National Parks: 2008 Annual Performance & Progress Report" Natural Resource Report NPS/NRPC/ARD/NRR—2009/151 by the National Park Service - U.S. Department of the Interior [http://www.nps.gov/yose/naturescience/upload/AQ.Trends.Parks.2008.pdf]

"Related Topics." Plant Science Research : Ozone effects on plants. N.p., n.d. Web. 20 Nov. 2013. <http://www.ars.usda.gov/Main/docs.htm?docid=12462>.


How To Improve Human Impacts on the Sierra Nevada

Ever since the day's of Bush administration, there have been a large pushes for unstable logging and harmful practices on the national forests of the Sierra Nevada. In January 2004, the Sierra Nevada Forest Plan amendment was approved which nearly tripled the amount of logging allowed in the Sierra Nevada. With a constant economic push to produce more lumber, many corporations seemed to back such amendments as they would benefit from the loosened limitations. Unsurprisingly, the public did not take these amendments positively, and through the means of organizations such as the Sierra Club, the public have been able to challenged the amendments through formal administrative appeals. 

The best way to improve human impacts on the Sierra Nevada is to increase awareness on what is occurring in the ecosystem and how it is crucial that we maintain an ecosystem that is so important to the state of California. Even by looking at the previous sections, it is clear that humans have been a negative impact to the Sierra Nevada ecosystem. However, through awareness, individuals would be more able to make informed decisions when coming down to issues such as voting for future amendments or laws that may either harm or benefit the Sierra Nevada.


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


References

Aerial view of Sierra Nevada
http://upload.wikimedia.org/wikipedia/commons/1/1c/Sierra_Nevada_aerial.jpg

Map of Area
http://power.arc.losrios.edu/~reevesl/assignments/images/map_ca.jpg

Historic Railroad Photo

http://upload.wikimedia.org/wikipedia/commons/2/23/Chinese_railroad_workers_sierra_nevada.jpg

Historic Town Photo

http://www.usace.army.mil/About/History/HistoricalVignettes/CivilEngineering/081LoneliestRoad.aspx

Current Mountain Range Photo
http://upload.wikimedia.org/wikipedia/commons/1/1c/Sierra_Nevada_aerial.jpg

Sierra Nevada Natural History

http://books.google.com/books?hl=en&lr=&id=-bSdQh_e8j0C&oi=fnd&pg=PA1&dq=history+of+sierra+nevada&ots=BUZI1JTwVx&sig=vSY_xi7Wi5RrsQyR_3dQ5VhNq-M#v=onepage&q=history%20of%20sierra%20nevada&f=false

Encyclopaedia Britannica: Sierra Nevada - The people and economy

http://www.britannica.com/EBchecked/topic/543431/Sierra-Nevada/39952/Plant-life#toc39954

Air Quality in National Parks: 2008 Annual Performance & Progress Report" Natural Resource Report NPS/NRPC/ARD/NRR—2009/151 by the National Park Service - U.S. Department of the Interior http://www.nps.gov/yose/naturescience/upload/AQ.Trends.Parks.2008.pdf

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