Name: how humans change biodiversity
Uploaded: 2019-03-11T09:21:43.000Z
Duration: 1 min 50 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Biology

ecosystems-interactions-energy-and-dynamics

Ecosystems- Interactions, Energy, and Dynamics

LS.Bio.5.2

Threats to Biodiversity

- [나레이터] 비록 생물 다양성이지질학적인 시간 동안 변화해 왔지만,지구 역사 전체에 걸친5번의 주요한 대멸종의 결과로증가와 감소를 반복합니다.현재의 홀로세 절멸로 알려진여섯 번째 대멸종은인간의 활동 때문입니다.인구폭발은 현재의 생물 다양성감소의 핵심 원인으로서식지 감소, 무분별한 개발,침습종의 유입, 기후 변화에따른 결과 입니다.인간의 식량과 거주지를 위한 자원의 필요성이 크게증가함에 따라 많은 생물 종들이 서식지를 잃게 되었습니다.산림 파괴와 농업을 위한 토지 변경은생물 종들을 서식지에서 몰아내고 거주 범위를축소하고 파괴하여 이용 가능한 자원을 감소시켜생존 위협을 증가시켰습니다.식량과 약품에 사용되는 수많은 생물 종들이지나친 학대로 종 스스로의 회복 능력을 상실하고 있습니다.이러한 원인은 생물 종들의 번식 능력을 초과하는높은 경제적 수요에 의한 것입니다.더욱이 침습종 유입의 결과로자원에 대한 포식 경쟁을 통해토착종을 몰아내는 급격한생태계 변화를 초래했습니다.천적이 없으면 침습종은 급격한생물 다양성 감소를 유발합니다.마지막으로 이산화탄소 및기타 온실가스의 배출량 증가는지구 평균 기온을 점진적으로상승시켜 왔습니다.이러한 영향으로 많은 생물 종들의거주지가 줄어들었고 철새의계절별 행동 패턴을 변화시켰습니다.

맥레먼, 로버트 A., 줄리엣 듀프레, 레아 베랑 포드, 제임스 포드, 콘라드 가예프스키, 그레고리 마칠든."우리가 더스트 보울에서 배운 것: 과학, 정책, 적응의 교훈." 인구와 환경 35, no. 4 (2014년 6월 1일): 417–40. [<a href="https://doi.org/10.1007/s11111-013-0190-z" target="__blank">소스</a>]

Dobson, Andy P. "옐로스톤 늑대와 자연 시스템을 구조화하는 힘." PLoS Biology 12, no. 12 (2014년 12월 23일). [<a href="https://doi.org/10.1371/journal.pbio.1002025" target="__blank">소스</a>]

Bar-On, Yinon M., Rob Phillips 및 Ron Milo. "지구상의 바이오매스 분포." Proceedings of the National Academy of Sciences 115, no. 25 (2018년 6월 19일): 6506. [<a href="https://doi.org/10.1073/pnas.1711842115" target="__blank">출처</a>]

생물다양성에 대한 위협

지질 역사를 통틀어 다섯 가지 주요 멸종 사건이 발생해 생물다양성이 없어졌고, 그 뒤를 이어 새로운 조건에 적응한 종들이 다시 생겨났습니다. 현재 지질시대인 홀로세(Holocene)에는 여섯 번째 멸종이 진행되고 있습니다. 이 대멸종은 인간의 활동에 기인하며, 따라서 현시대를 잠정적으로 인류세(Anthropocene)라고 부르기도 합니다. 2019년 인구는 77억 명에 달했고 2060년에는 100억 명이 될 것으로 추산됩니다. 생물량(biomass; 특정 종의 실제 질량; 바이오매스)으로 나타낸 우리의 영향을 들여다보면, 인간은 지구 포유류의 36%를 차지하고, 가축은 60%, 야생 포유류는 4%에 불과합니다. 또한 모든 새의 약 70%가 가금류이고 30%만이 야생입니다.
 
 생물다양성과 기후에 대한 인간의 영향을 최소화하기 위해서는, 우리는 어떤 활동이 문제인지 이해하고 미래 세대를 위한 지속 가능한 계획과 인류 문명의 요구 및 발전 사이의 균형을 맞춰야 합니다. 생물다양성에 대한 주요 위협 중 일부는 인간의 개발로 인한 서식지 감소, 과도한 농사, 그리고 공장과 차량의 이산화탄소 배출 증가를 포함합니다.
 
 <h4>사례 연구</h4>
 
 인간이 날씨에 미치는 영향에 대한 사례 연구는 더스트 보울(Dust Bowl)이라고 알려진 1930년대 사건을 통해 알아볼 수 있습니다. 1920년대와 1930년대에 많은 농부가 대평원으로 이주하여 땅을 개간하고 일반적으로 뿌리가 얕은 농작물을 심기 위해 식물을 덮는 토종 땅을 제거했습니다. 캔자스와 텍사스 북부 지역을 중심으로 북쪽으론 캐나다, 남쪽으론 텍사스까지 달하는 지역에서는 극심한 가뭄과 제대로 고려되지 않은 농업 관행의 조합으로 먼지 폭풍이 일었고, 이로 인해 북동부 주까지 잔해가 쌓이게 되었습니다. 당시 이러한 폭풍과 겹친 경기 침체 때문에 전반적인 식량 부족이 생겼고 많은 가정이 농장을 포기해야만 했습니다. 이 사례를 통해 토지가 자연적으로 적응되지 않은 단일 식물 종을 지원하기 위해서는, 생물다양성의 손실을 감안하여 농장을 계획해야 한다는 것이 분명해졌습니다.
 
 덜 극단적인 예는 미국의 옐로스톤 국립공원에서 볼 수 있습니다. 그 지역의 늑대 개체군은 인구가 서쪽으로 이주하기 시작한 이후 급격히 줄어들었습니다. 그 결과, 가지뿔영양과 노새 사슴과 같은 피식자 동물의 수가 증가했습니다. 그 동물들은 어린 백양 묘목을 먹는 경향이 있기 때문에 피식자 동물의 증가는 백양나무의 쇠퇴를 초래했습니다. 나무 손실의 하류 효과는 땅 침식의 증가와 새와 다른 동물들의 서식지 감소를 불러왔습니다. 이와 같은 일련의 사건들을 뒷받침하는 증거는 최근 옐로스톤에 늑대를 재도입한 뒤 공원 내 백양나무 개체군이 증가한 것을 관찰한 것에서 비롯됩니다. 늑대 재도입과 백양나무 증가 간 상관관계가 실제로 늑대의 재도입으로 발생했다는 인과 관계를 보여준다면, 이 연구는 생태계의 생물다양성에 최상위 포식자가 필수적이라는 일반적인 개념을 뒷받침합니다.
 
 생태계를 균형 있게 보전하고, 예측 가능한 기상 패턴을 유지하고, 새로운 산업 및 의료 제품 연구를 위한 원료를 유지하기 위해서는 생물다양성의 유지관리가 중요합니다.

지질학 역사를 통틀어 다섯 번의 주요 멸종 사건이 있었으며, 그 결과 생물 다양성이 제거되고 종의 반등이 뒤따랐습니다.

Education

교육

JoVE Core

생물학

Ecology

생태학

Biodiversity and Conservation

생물다양성과 보존

KEY TERMS AND CONCEPTS

주요 용어 및 개념

how humans change biodiversity

Human activity is changing biodiversity and pushing Earth toward a sixth extinction event. Earlier mass extinctions ended many species, and then new species spread into the changed environment. Today, the Holocene epoch is seeing a mass extinction linked to human actions, and it is often called the Anthropocene.

Human numbers and human biomass show how large this impact has become. In 2019, the human population reached 7.7 billion and is projected to rise to 10 billion by 2060. By biomass, humans make up about 36% of Earth’s mammals, livestock make up 60%, and wild mammals only 4%. About 70% of all birds are poultry, so only 30% are wild birds.

Several common activities threaten biodiversity. Habitat loss can happen when land is cleared for human development. Over-farming can also damage ecosystems. In addition, factories and vehicles release carbon dioxide, which adds to climate problems. To reduce these effects, people need to understand which activities cause harm and find a sustainable balance between human progress and the needs of future generations.

The Dust Bowl is one clear case of human impact on land and weather. In the 1920s and 1930s, many farmers moved to the Great Plains and clear cut the land. They removed native ground-cover plants so they could plant crops with shallow roots. Then extreme drought and poor farming practices combined to create dust storms that spread debris as far as the northeastern states. Food shortages followed, and many families had to leave their farms.

The Dust Bowl shows that farmland must be planned carefully if it is to support single crop species that are not naturally adapted to the area. A different example comes from Yellowstone National Park. After people moved west, wolf populations dropped sharply. Prey animals such as pronghorn and mule deer increased, and they ate young Aspen saplings. Aspen trees declined, which led to more erosion and less habitat for birds and other animals.

Wolves were later reintroduced to Yellowstone, and the Aspen population has since shown a rebound. If this pattern is truly caused by the return of wolves, it supports the idea that apex predators help keep ecosystems balanced. Biodiversity also matters because it helps preserve stable ecosystems, supports more predictable weather patterns, and keeps raw material available for new industrial and medical products.

How Humans Change Biodiversity

what is weather?

How Sunlight Shapes Daily Weather

Weather is the current state of the atmosphere at a specific time and place. It is temporary and changes from one location to another. Weather is shaped by the interaction of the sun, atmosphere, hydrosphere, and geosphere. Solar radiation reaches Earth and interacts with water and land. These surfaces release that energy as thermal radiation, or heat, which warms the air above them. Some of that heat escapes back into space, but some is trapped by atmospheric gases. This heat retention is...

global climate change

Ancient Clues to Climate Change

Ancient climate clues help scientists track global climate change. Paleoclimatology is the study of climate conditions in Earth’s past and the causes and effects behind them. By comparing recent climate patterns with older records, researchers can find strong evidence for human-caused warming. Earth’s climate has changed many times over its 4.5 billion year history. In the last 650,000 years, there have been seven cycles of glacial advance and retreat. The most recent ice age ended more than...

what is biodiversity?

Biodiversity Across Genes, Species, and Ecosystems

Biodiversity is the variety of living things at the genetic, species, and ecosystem levels. It includes not only how many kinds of organisms exist, but also how they are related and how they interact with the world around them. Species diversity spans the full evolutionary tree. It includes single-celled prokaryotes such as bacteria and archaea, as well as the eukaryotic kingdoms: plants, animals, fungi, and protists. About 1.75 million species have been identified so far, and scientists...

threats to biodiversity

Human activity is changing biodiversity and pushing Earth toward a sixth extinction event. Earlier mass extinctions ended many species, and then new species spread into the changed environment. Today, the Holocene epoch is seeing a mass extinction linked to human actions, and it is often called the Anthropocene. Human numbers and human biomass show how large this impact has become. In 2019, the human population reached 7.7 billion and is projected to rise to 10 billion by 2060. By biomass,...

conservation of declining populations

Saving Species Through Population Recovery

Conservation of declining populations focuses on detecting a population drop, finding its cause, and stopping further loss. The goal is to prevent extinction by using scientific methods to identify the agents behind the decline. Once the cause is known, conservation teams can remove, oppose, or neutralize it. A common step is to test possible causes with a small trial group. If the cause is confirmed, the remaining animals may be moved to an unaffected area. When the population is too small or...

biodiversity and human values

Biodiversity in Food, Tools, and Medicine

Biodiversity supports human life through food, tools, medicine, and many other needs. Changes in the variety of species can also change the environment. Those environmental shifts can alter weather patterns and affect human civilizations. People have depended on biodiversity for agriculture since early human history. Agriculture began when ancestral humans found species that were good sources of food. At least 11,000 years ago, people started selecting plant and animal species to raise on...

what is conservation biology?

Protecting Biodiversity in Conservation Biology

Conservation biology is the science of protecting biodiversity and keeping ecosystems healthy. It looks at how living things, habitats, and human needs are connected. The goal is to preserve biodiversity so ecosystems can continue to function well. Healthy ecosystems provide people with important natural resources. These include food, medicines, and building materials. Ecosystems also deliver key services, such as cleaning air and water. Evidence shows that these services depend on...

what is climate?

Climate Patterns and Earth’s Energy Balance

Climate describes the usual weather conditions in a place over a long period of time. The idea is simple: climate is what you expect, while weather is what you get. Climate is shaped by geographic factors such as latitude, terrain, and how close an area is to bodies of water. Weather and climate are related, but they work on different time scales. Weather is the state of the atmosphere at a specific time and place. Climate is the average pattern of weather over much longer periods. Because of...

sustainable development

Protecting Oceans for Sustainable Development

Sustainable development depends on protecting oceans while meeting human needs. As the human population grows and uses more resources, people must stay aware of the planet’s natural limits. The goal is to improve life now without taking away the resources future generations will need. Long-term sustainability depends on understanding how human actions affect ecological systems. Oceans are a major part of this balance. They provide food for people, produce much of the atmosphere’s oxygen, and...

conservation of small populations

Saving Small Populations with Genetic Diversity

Small populations can be hard to save because they often lose genetic diversity. When variation is low, a species has fewer traits that may help it adapt to climate change, competition from other species, or new diseases. That makes extinction more likely. Large populations usually have a better chance of surviving new stresses. They are more likely to include individuals with genetic variants that are helpful in changing conditions. Small populations are much less likely to contain this kind...

habitat fragmentation

How Fragmented Habitats Affect Wildlife

Habitat fragmentation breaks one continuous habitat into smaller, separate patches. Human land conversion is a major cause of this change, and slower geological shifts in the physical environment can also fragment habitats. The process usually follows the same stages: perforation, dissection, fragmentation, shrinkage, and attrition. Perforation and dissection often begin during land development. Perforation happens when undeveloped land is cleared for something like a home, and dissection...

key terms and concepts

Learn how human population growth, habitat loss, over-farming, and carbon emissions affect biodiversity. Includes the Dust Bowl and Yellowstone wolf example.

How Humans Change Biodiversity | JoVE K12

JoVE Core series brings biology to life through over 300 concise and easy-to-understand animated video lessons that explain key concepts in biology, plus more than 150 scientist-in-action videos that show actual research experiments conducted in today’s laboratories.

biology

JoVE Core 시리즈는 생물학의 주요 개념을 설명하는 300개가 넘는 간결하고 이해하기 쉬운 애니메이션 비디오 강의와 오늘날 실험실에서 수행된 실제 연구 실험을 보여주는 150개가 넘는 과학자 활동 비디오를 통해 생물학에 활기를 불어 넣습니다.

How Humans Change Biodiversity

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