ALASKAN ALPINE TUNDRA
By: Zainab Umarji, Melina Melgoza, Nicharee Nalumpoon, and Ivan Cai
By: Zainab Umarji, Melina Melgoza, Nicharee Nalumpoon, and Ivan Cai
History of Ecosystem
In Alaska, nearly half of the land is
covered by tundra, a type of land ecosystem that does not have any large trees because of the particularly low temperatures in high altitudes. We are especially
focusing on Alpine tundra in Alaska, which appears in mountain ranges above the
tree line elevation and exposed ridges in Alaska.
Miles of Coastline in Alaska are the main contributions to the
distribution of tundra. Since tundra
occurs where the average temperatures are low, the winter of the Alaska is long and cold. Tundra forms along the coast line in coastal areas with freezing cold oceans, causing there to be much cooler summers that are rarely above 50 degrees F. Humans have been living in the tundra ecosystem for thousands of years and these people include The Aleut, Alutiiq, Inupiat, Central Yup’ik and Siberian
Yupik are the indigenous people of Alaska’s tundra regions. During the past 50
years, humans have had a big influence on the tundra and there are big changes as the
result of modern human activities. Historically, fire was ware in the tundra of Alaska, however, through recent years,
warming temperature and drier climate has caused more lightning in the Alaska
tundra regions. In 2007, the largest tundra fire on historical precedent happened in
Alaska’s
North Slope.
Human Impact on Alaska Alpine Tundra
This region has an environment of extreme cold, very little precipitation, and very little vegetation diversity. It covers about one tenth of the earth’s land but most of the areas are frozen bogs (Melford 2005). This environment is very harsh for many living organisms and difficult for them to thrive, including human. There are not a lot of human population in this region. Therefore, the urban development is not a major problem. Human impacts on the land is relatively low compare to other ecosystems. However, we have used the land to get some natural gases, such as oil, and have used it for recreations, such as resorts. The biggest threat in this region is considered to be oil and natural gases, the development of transportation for these substances, and the impact on animal habitats. Human settlement in nearby regions also create some effects on air pollutants and emission of the other greenhouse gases that can have major influences for organisms in the long run.
Some human impacts that we would like to cover are the following:
- Oil Production and Transportation
- Impact on Animals and Their Migration Paths
- Recreations and Resorts
- Climate Change and Global Warming
1. Oil Production and Transportation
Millions of barrels of oil were found in this region, and it has become very useful for our consumption (Burak et al. 2008). People built long pipelines in order to transport the oil from Alaska to the United States. There are both good and bad consequences in constructing the pipelines. The pipeline is necessary for oil companies to ship oil from the region at the vast rate of current consumption. We get benefits from the oil and natural gases found in the region, but building pipelines cost billions of dollars (Burak et al. 2008). Having such huge and long pipelines across the state of Alaska can be risky for the oil to spill out. Spilling oil from the pipeline have negative consequences on the ecosystems such as on plants and animals. However, using pipelines to transport oil from Alaska is more efficient than using roads. If we use roads, a number of trucks would be needed for transportation and large amount of pollution from the vehicles would be released (Burak et al. 2008). The debate nowaday has been whether it is worth it to spend all the money to continue the pipeline project or should we build roads instead.
The Map of Pipeline in Alaska
Pipelines in Alaska
The pipelines in Alaska disturb the
migration path of animals that are native to the area. These pipelines act as
fence barrier and block animal migration paths. Caribou is native to the
region; they migrate in large herd northeastward across Alaska and Canada in
spring for more food source (Roseneau
et al. 1974). Caribous are large animals that live in big herds. Because the
alpine tundra has limited diversity of plants, these grazers need to migrate to
different region (Canada) in spring to find more food. They migrate back months
later to allow the plants and grasses to grow. When people put the pipelines,
these caribou are not able to walk across the region. They are trapped in
Alaska. As a result of the pipeline construction, the caribous cannot cross the
land to find more food. They graze too much on the land eating all the native
vegetations causing the imbalance of plants species. This might eventually
result in the collapse of the entire ecosystem (Walker and Everett 1987).
Arctic Fox in Winter
Arctic Fox in Winter
Black spruce-scrub
Mountain avens
Dwarf willow birch
Ericaceous shrubs
Lichens
Many of the alpine flora share similar characteristics which have allowed them to adapt to and survive the cold and severe climate of the Alpine tundra.
Moose
Common Ravens
Fauna of the Alpine Tundra have also many adaptations to help them survive the cold and harsh climate of the Alpine Tundra. Most fauna have the following:
The fauna of the Alpine Tundra have diets that are suitable for the biome. Animals, such as the fox and wolf, are carnivorous and eat other animals, like birds and caribou. The hare and moose are herbivores and rely on plants, and sometimes small insects to survive
(Biomes, 2007)
Human impacts on Alpine Tundra Flora and Fauna:
What can be done to improve?
The Alpine Tundra in Different Languages
Alpine Tundra Video
Video with many beautiful pictures of the Alpine Tundra in its different seasons, as well as, a descriptive chart of the animal food web.
http://www.youtube.com/watch?v=RdFEaOhQDds
Migration Path
Migration Path
Migration Path
3. Recreations and
Resorts
Alaska is a famous place for winter
recreation. One of the most popular activities is skiing. Tourists from many
parts of the world come to Alaska to enjoy the beauty of winter and to ski.
Many resorts were built within the past decades to accommodate tourism industry
(Buckley 2004). The benefit is for the tourists to experience alpine tundra
ecosystem and wildlife. Moreover, roads were also built for people to get to
those resorts. These have influenced the migration path of large animals as
well as the construction of pipelines (Buckley 2004). Roadkills are one of the
major problems for these animal; many elks are killed each year due to the
transportation and vehicles.
Ski Resorts
Ski Resorts
4. Climate Change and
Global Warming
Building
roads and resorts and in Alaska alpine tundra caused the overall temperature to
increase. The settlement of human in this region and the nearby regions have
impacted Alaska alpine tundra. Urban development results in permafrost melting,
coastal erosion, increase hazard natural storms, and releasing of methane gas,
which is one of the most important greenhouse gases (Hinzman et al. 2005). The
impacts of this has resulted in changing and adapting of organisms in the
tundra ecosystem. The increasing in temperature also affect the rising in sea
level due to the melting ice caps of the north pole (Cooper 1989). Winter in
this region is predicted to become warmer which can affect native vegetation.
These native plants have adapted to extreme cold environment. By changing the
composition (Ims and Fuglei 2005).
Animals
have also been impacted by the consequences of climate change and the
increasing in temperature. Polar bears need big chunk of ice sheets to rest on
after swimming for food in order not to exhaust themselves to death. However,
they don’t have as much ice sheets anymore because the ice has been melting so
much lately. Arctic foxes also receive the influences of the climate change
(snow melts faster). They have white thick fur in order to blend in with the
snow in winter. Interestingly, their fur changes color in summer to become more
brown to blend in with the warmer environment. The fur changes colors based on
the length of day not the amount of snow that is on the ground. Because the
snow melts faster than usual, they cannot hide themselves as good and a lot of
them have been eaten by bigger animals, including polar bears (Ims and Fuglei
2005). Their population has decreased drastically in the past decades.
Climate Change in Alaska
Arctic Fox in Winter
Arctic Fox in Winter
Climatic Classifications
The climate of the Alpine Tundra is fairly arctic, with a minimum of one month averaging high enough to defrost. This temperature would be about 0°C or 32°F. With that said, there is no month that has an average excess of 10°C or 50°F. The winters are very cold and there are many months of freezing. The weather conditions are very severe and the winter season can sometimes last from October all the way to May. The Alpine Tundra is known for its location in very high mountainous areas that are above the tree line and usually at an altitude of about 10,000 feet or more. Overall, the climatic classifications of the Alpine Tundra are pretty straightforward with cold temperatures, and averages that never go past 50 degrees Fahrenheit. The temperature allows for very winter-themed recreation and resorts
Interior Yukon-Alaska Alpine Tundra
Alaskan Alpine Tundra
http://b.static.trunity.net/images/212709/754x461/scale/interior-yukon-alaska-alpine-tundra-map.png
Alaskan Alpine Tundra
Alaskan Alpine Tundra
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh2JMESIInpYjm28xOBpGQpLQ5C9QxqEgSHrZA3WtZB1amAdVmPakwUPSxd4OMJJF5CxrdDjeb-o-a-e8ALnuiiaN51go_SKl7-7lUPo932JbUL0k8O4fpTkVx_R2Ha1qaY09uGix-SrB2W/s1600/DSC_3866.JPG
http://alpine.forestry.ubc.ca/files/2013/02/Card1a-097.jpg
Diversity: Flora and Fauna
Alpine Tundra Plants and Trees
Lower Elevations
Lower Elevations
Black spruce-scrub
Lodgepole pine
Higher elevations
Mountain avens
Dwarf willow birch
Ericaceous shrubs
Lichens
- Most of the alpine flora is perennial, meaning it lasts for more than one year— during the winter, they don’t die; they save their shrubs, leaves, and roots in the ground.
- During the spring and Summer, plants keep moisture in so that during the winter, the winds don’t dry the plants out.
- The roots are mostly shallow, due to the thin soil.
- Because of the lack of nutrients in the soil, many plants are small and grown close to the ground. Many plants grow in clumps, in order to survive harsh winds and warm each other during the cold.
- Alpine plants with flowers absorb heat through the flower, allowing them to grow quicker and healthier.
- Some plants save extra nutrients in bulbs and roots for the next growing period.
- One very important and essential adaptation of the alpine flora is that they must grow very quickly during the growing period, because the growing period is usually ranges from 10 to 24 weeks.
(Tundra, 2007)
Trees:
Like the small plants, alpine trees have adapted to the harsh climate.
- Many trees are coniferous trees- these trees keep their leaves throughout the year.Because of this, they are able to start food production quickly when the growing season starts. Coniferous trees also sometimes have narrow needles—when the harsh winter winds hit, there is less surface area to be damaged.
(What are Coniferous Trees, 2003)
Alpine Tundra Fauna
Caribou
Caribou
Grizzly and Black Bears
Moose
Common Ravens
Fauna of the Alpine Tundra have also many adaptations to help them survive the cold and harsh climate of the Alpine Tundra. Most fauna have the following:
- Arms that are short and plump
- Thick feathers and furs for insulation
- Feathers and furs that change according to the seasons:
- Brown =summer
- White =winter
- Thick, fat layer from spring time= energy and warmth when it gets cold during the winter
- Adapted to prevent bodily fluids from freezing
(Biomes, 2007)
(Biomes, 2007)
Humans have a severe impact on the wildlife of the Tundra:
Due to the increase in air pollution, many plants, including the lichen, have become contaminated by the smog clouds. The lichen in particular is a very important food source for many animals.
Furthermore, the construction of pipelines and roads has led to habitat loss for a large number of the wildlife. (National Geographic)
Due to these impacts, many Alpine Tundra fauna are on the endangered species list, including:
- The grizzly bear (endangered due to shortage of food)
- The dall's sheep
- The caribou (Weiss- Rosselar)
Likely Future Prospects
In general, Alaskan Alpine Tundra is currently under little impacts from human urbanization development but greatly on oil and natural resources transportation. This matter has created pollution that accumulated in the region which has great impacts on native plants and animals. The spill of the oil from the transportation is risky because it will contaminated the soil and damage the environment (Wilmking et al., 2004). The problem may lead to extinction if there is no improvement in transportation system that favors animals habitats. Moreover, the global warming and increasing in temperature has been a major issue to this region because it will change the composition of the ecosystem. If the weather continues to get warmer, native plants and trees might adapt by growing taller and change the forestation pattern, which will affect animal habitats. The ground temperature will also increase as the over temperature rises and melt the permafrost (Wilmking et al., 2004). If the trend continue this way, the future of the Alaska Alpine Tundra region might not be as good. Therefore, we need to conserve this region before it becomes too bad.
These are some ideas that can help us minimize the environmental damages and improve the ecosystem of the alpine tundra in Alaska.
1. Use alternative energy sources to minimize human-made global warming effects
2. Government should have strict laws and regulations to protect animal conservation areas to reduce human influences
3. Limiting pipeline and road construction in Alaska tundra in order not to disturb animal habitats as much
4. Build overpass for the animals to migrate across the pipelines or under the roads
5. Encourage tourists to respect local culture and the ecosystem
6. Introduce native vegetations back to the region as food supply for the animals
The Alpine Tundra in Different Languages
We have also provided you with the information as an abstract in three different languages- Thai, Chinese, and Spanish. We hope you enjoy our blog any get useful information from it. Thank you for visiting.
1. Thai (by: Nicharee Nalumpoon)
ระบบชีวนิเวศเขตขั้วโลกเหนือ (ทุนดรา หรือ Alpine Tundra)
โดย นางสาวณิชารีย์ ณ ลำพูน นักศึกษาปริญญาตรีจาก UCLA ในรัฐ California
ระบบชีวนิเวศทุนดรา เป็นระบบนิเวศที่อยู่ในเขตอาร์คติก (Arctic) ตั้งแต่ประมาณเส้นรุ้งที่ 60 องศาเหนือขึ้นไปทางขั้วโลกเหนือ มีอุณหภูมิเฉลี่ยสูงสุดไม่เกิน 10 องศาเซลเซียส อยู่ทางทวีปอเมริกาเหนือ ยุโรบ และแถบไซบีเรีย ระบบชีวนิเวศนี้ ยังสามารถพบได้ในบางพื้นที่ของโลกที่มีเทือกเขาสูง มีหิมะปกคลุมบนยอดเขาช่วงฤดูหนาว หรือในภาษาอังกฤษเรียกว่า Alpine Tundra ในรายงานชุดนี้ เราต้องการศึกษาและเน้นรายละเอียดเกี่ยวกับทุนดราในมลรัฐอลาสกา ของประเทศสหรัฐอเมริกาเท่านั้น
ด้วยอุณหภูมิที่ต่ำมาก บวกกับปริมาณความชื้นที่ต่ำ ทำให้ระบบชีวนิเวศนี้ ไม่มีความหลากหลายทางด้านพืชพันธุ์และสัตว์มากเท่ากับระบบชีวนิเวศอื่นๆในธรรมชาติ พืชในระบบนิเวศนี้มีฤดูการเจริญเติบโตสั้นเนื่องจากไม่ได้รับแสงอาทิตย์มากนัก มีหิมะปกคลุมเกือบตลอดทั้งปี รวมทั้งยังมีน้ำและดินที่แข็งตัว (Permaforst Tundra) ทำให้เป็นตั้วกั้นการเจริญเติบโตของราก พืชส่วนใหญ่จึงเป็นหญ้าเช่นพวกหญ้ากก (grass) หญ้าทรงกระเทียม (sedge) หากเป็นต้นไม้ก็เป็นต้นไม้แคระ มีลักษณะเป็นพุ่มเตี้ย (dwarf wood plants) เป็นต้น
สัตว์ที่สามารถปรับตัวให้อยู่ในสภาพแวดล้อมนี้ได้ จำเป็นที่จะต้องมีสภาวะร่างกายที่เหมาะแก่อุณหภูมิที่หนาวเย็น เช่นมีขนที่ยาวและหนา หรือสามารถปรับเปลี่ยนสีขนให้กลมกลืนไปกับสภาพแวดล้อมเมื่อฤดูเปลี่ยน ตัวอย่างสัตว์ในบริเวณนี้ได้แก่ กวางแคริบู กวางเรนเดียร์ หมีขั้วโลก หมาป่าขั้วโลก กระต่ายป่าขั้วโลก และ นกฮูกหิมะ เป็นต้น สภาพแวดล้อมของระบบชีวนิเวศแห่งนี้ เมื่อเทียบกับแห่งอื่นๆแล้ว ไม่ได้รับผลกระทบจากการตั้งถิ่นฐานของมนุษย์มากเท่าไหร่นัก เนื่องจากมีอุณหภูมิที่ต่ำ ปริมาณน้ำฝนน้อย ทำให้ยากต่อการดำรงชีวิต แต่ระบบนิเวศนี้ได้รับผลกระทบมาจากการขุดเจาะและขนส่งน้ำมัน รวมถึงขุดค้นหาแร่ธาตุอื่นๆทางธรรมชาติ การกระทำดังกล่าวทำลายถิ่นที่อยู่ของสัตว์ป่า ความหลากหลายทางธรรมชาติ และขัดขวางการอพยพเพื่อไปหาอาหารของสัตว์ฝูงใหญ่ อาธิเช่นกวางแคริบู การรณรงค์การท่องเที่ยวในบริเวณนี้ ก็มีส่วนทำให้ระบบนิเวศได้รับความเสียหาย แต่อยู่ในระดับที่ร้ายแรงน้อยเมื่อเที่ยบกับระบบนิเวศอื่นๆ รายละเอียดเพิ่มเติมเกี่ยวกับระบบชีวนิเวศนี้ ท่านสามารถอ่านได้ในภาษาอังกฤษด้านบนค่ะ
2. Chinese (By: Ivan Cai)
阿拉斯加有近一半的土地是高山苔原,高山苔原生态系统没有高大的树木,因为它形成的气候原因是低温高海拔,阿拉斯加的高山苔原主要分布于西海岸线因为这里的气温更低海拔相对更高。阿拉斯加的冬天时间长而寒冷,夏天时间断而且温度也相对较低,来自海洋的低冷气压使这里的冬天更冷。几千年来,这里就有人类活动的影子,有不少的原住民生活在这里。然后,过去的50年里,人类活动对阿拉斯加高山苔原生态环境造成了很大的影响甚至是破坏,2007年一场史无前例的大火侵袭了阿拉斯加苔原。
阿拉斯加高山苔原的植物种类并不繁多,因为大部分都是冻土多数植物无法很好的生长,所以人类也无法在这里很好地进行城市建设,但是,由于大量的自然资源,高原冻土被人们大量开发。天然气,稀土都是高山苔原的资源。不仅如此,人类的影响范围还包括动物的栖息地还有他们迁徙的路途。
我们可以做些什么去保护阿拉斯加的高山苔原生态系统呢?
使用新生的无污染能源,限制人类在野生动物栖息地内的活动,给迁徙的动物建造过道,鼓励旅游者们尊重当地的文化习俗和生态系统。
3. Spanish (By: Melina Melgoza)
La tundra alpina es parte de la
vegetacion selvatica en los lugares altos, por ejemplo montanas. En las
montanas el clima es muy similar a ese
de el arctico. La tundra alpina tiene plantas muy pequenas y muchas flores que
estan acostumbradas a las bajas temperaturas que occurren en estos lugares
frios. El bioma de el cual estamos hablando nosotros
esta localizado en Alaska. En Alaska casi la mitad de la tierra esta cubierto
en tundra. El impacto de los humanos es en una region de mucho frio, poca
lluvia, poca vegetacion, y casi 10% de el mundo esta cubierto de areas de
hielo. Algunos de los impactos de los humanos son la produccion y
transportacion de aceite, el impacto de los animals recreation y lugares
divertidos, y el cambio climatico y calientamiento global.
Las caracteristicas de la Tundra
Alpina son que esta localizada a partir de los 50° latitud Norte y Sur. La
temperature climactica es de 5° a 7°C y
en vierno de -40 °C. Las lluvias en esta
vegetacion selvatica son en forma de nieve y el aire es frio y seco. La tundra Alpina tambien tiene muchas diferentes especies de animales que estan muy bien adaptadas al clima! Regresando a la temperatura, la Tundra Alpina presenta un permafrost que es delgado en regionas montanicas muy altas. El
nombre de el bioma representa “montanas altas.” Alpina viene de la palabra que
significa montanas altas. Y el nombre es muy representativo de lo que representa. La Tundra Alpina casi siempre existe en lugares montanosos y es muy importante reconocer que la Tundra Alpina existe en lugares increiblemente frios. Lo frio de este bioma es lo cual lo ayuda a tener ciertas actividades divertidas de recreacion a la cual hace que personas vengan a visitar. La Tundra Alpina es muy interesante y nos encantaria visitar algun dia!
Alpine Tundra Video
Video with many beautiful pictures of the Alpine Tundra in its different seasons, as well as, a descriptive chart of the animal food web.
http://www.youtube.com/watch?v=RdFEaOhQDds
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