Water and Carbon Cycles - The Amazon Rainforest

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

- National Government set a target of "One Billion Trees for the Amazon" from 2008-2030 in Para, Brazil. - Protect the land from unsustainable logging and agricultural practices that have blighted parts of the Amazon. Why: To replenish part of Amazon rainforest as 90% Para's land has been deforested. Consolidate image of Para as guardian and restorer of Amazon. Protect 1000's of wildlife species, e.g Jaguars and colourful Macaws. How: Plant 1b trees on deforested land by 2013 and reduce global levels of greenhouse gases by 5% until 2030. Restore legal and environmental reserves in Para. Develop new economic model for more sustainable practices.

Afforestation

- Implemented by GIZ on behalf of governments of Germany and Netherlands, established 2002 in Amazon countries. - Strengthening the capacities of the regional organisation ACTO. Sustainable policy at ecological, social and economic level regarding management of natural resources. Why: Sustainable development in Amazon and meet demands of Amazon countries. How: Coordinated manner in regional initiatives and actions for sustainable development. 4 support lines: 1. Support to regional and thematic forums. 2. Implementation of regional projects for sustainable development. 3. Creation of joint system for environmental and human capacity development. 4. ACTO institutional strengthening and network capacity internationally.

Amazon Cooperative Treaty Organisation

Atmospheric moisture, Precipitation, Interception storage, 1. Evapotranspiration, back to atmospheric moisture. 2. Stem flow 3. Drip flow Surface storage water in puddies, 1. Water in plant tissue, evapotranspiration (as above). 2. Evaporation from soil, back to atmospheric moisture. 3. Soil water, evaporation from soil.

Describe the Amazon water cycle.

CO2 from atmosphere, Trees absorb carbon via photosynthesis, 1. Leaf litter 2. Root cell respiration and death 3. Runoff 4. CO2 released through respiration by plants/animals and decomposers, back into atmosphere.

Describe the carbon cycle in the Amazon rainforest.

The low air pressure belt between the equator and Hadley Cell, and warm air converges at the Inter Tropical Convergence Zone (ITCZ), causing air mass to rise, cool and condense (evapotranspiration), forming clouds and therefore rain over the rainforest.

Describe the global atmospheric circulation system.

- 1/5 of world's biomass of carbon (stores 80-120b tons). - Forest size changed over time by shrinking & extending (covers 5.5m km2, 300 billion of world's trees). - Carbon sequestration has increased the productivity of rainforests. - The net uptake of forests has changed by half, due to increased CO2, meaning trees die faster. - Average rainfall 3,000mm, however 75% total rainfall is intercepted by dense canopy layer and then transferred to ground via stemflow. This is used by plants or is infiltrated through soil or flows overland into nearby channels. Evapotranspiration occurs to the remaining 25%. - Average temperature 28 degrees celsius, very humid climate (high humidity levels and unstable weather causes heavy rain most days).

General Facts

Forests play a crucial role in maintaining the global carbon budget, absorbing 2.4b metric tons of carbon/year (Amazon absorbs 1/4 of total). Wood is around 50% carbon, therefore rainforests act as a major carbon sink, and in return emit oxygen. Described as "lungs of the earth".

How do rainforests mitigate the effects of global warming?

Water: - Causes plants to decompose, imputing carbon into the soil which increases growth spurt of trees. The growth stimulation feeds them through the system much faster meaning they die younger. - Recycling of water system within tropical rainforest. - High precipitation, leads to a unique ecosystem. - Fast decomposition leads to a faster uptake of nutrients from the soil. Carbon: - Increases growth spurt of trees; the growth stimulation feeds them through the system much faster meaning they die younger. - Sequestering of increased CO2 concentrations in the atmosphere, results in increasing above ground biomass by 0.3-0.5% and increases productivity. - The increase in CO2 increases photosynthesis and therefore plant growth. - The rainforest acts as a major carbon sink, deforestation has decreased the CO2 uptake.

How do the water & carbon cycle and the rainforest influence each other?

- United Nations Educational, Scientific and Cultural Organisation (UNESCO), established 1980 in state of Amazonas. - World Heritage Site and Biosphere reserve covering an area of around 2m hectares. Why: To promote heritage, beauty and rich biodiversity to the public, encouraging protection of the rainforest. How: Creating tourist attractions: • Itaubal trail • Rapids of Carabinani and Jaú river • Petroglyphs • historical site of Airão

Jaú National Park

- South America - Equator in Southern Hemisphere - Passes through multiple different countries

Location

- 8 countries of Amazon Basin signed Amazon Cooperation Treaty (ACT) established 1978 in Amazon region. - Instrument for discussion and agreement and policies for a region complex and rich in natural resources. Criteria and indicators for the sustainability of Amazon forests. Harmonious development of region, raised standard of living and integration of Amazon country territories into respective national economy. Why: Strategies take into account natural renewal cycles and survival chains of fragile and diverse ecosystems. Identified economic potential of Amazon biodiversity and ways to use it more efficiently, the requisites for survival and reproduction of plant and animal species essential to a sustainable development. How: Mobilised vast network of public and private institutions and organisations and devised strategies for rational use of region's natural resources to benefit people.

Tarapoto Process

- Mining - Palm oil - Logging - Cattle ranches E.g. Slash and Burn: burning of trees to create farmland and fertilise soil with ash. This has increased due to higher demand for food, and it is a cheap and fast method to create useable land. Decreases water store and increases throughflow, reducing evaporation, therefore less clouds and rain. Throughflow carries the nutrients and minerals in the soil with it, making it harder for rainforests to recover. Furthermore, rotation of land occurs every 2/3 years as soil becomes infertile due to rainforests absorbing the majority of nutrients. - 30-60% carbon immediately released into atmosphere via method - Amazon shrinking by 0.3% since 2000

What are the drivers of change in the rainforest?

- Increased surface run-off causes a high risk of flooding. - Removal of trees through slash and burn reduces porosity of soil, resulting in faster rainfall drainage, erosion and silting of rivers and lakes. - Spracken et al 2012 found further deforestation in Amazon, could result in 20% decline in regional rainfall, as air blowing from rainforest contains less moisture.

What are the impacts of deforestation on the tropical rainforest water cycle? FLOODING

- Particles resulting from burning of trees increases density of airborne aerosols around which water vapour condenses. As a result, smaller droplets occur in clouds which are too small to precipitate therefore there is less local rainfall. - Forests emit salts and organic fibres along with water when they transpire. These act as condensation nuclei and assist in cloud and rain production. The loss inhibits formation of cloud and therefore rainfall. - Any moisture that does evaporate from deforested areas, form shallow cumulous clouds, which don't produce rain.

What are the impacts of deforestation on the tropical rainforest water cycle? RAINFALL

- As is that the transpiration is reduced the atmosphere becomes less humid. - Transpiration will rapidly decrease. - Less trees causes rainfall to be transferred straight to forest floor encouraging surface flow as the soil becomes dry and baked (exposed to the sun). - Reduced evapotranspiration from cleared areas mean air is less moist, causing a reduction in cloud cover. - Removal of trees through slash and burn, facilitates sudden evaporation of water that was previously retained in forest canopy.

What are the impacts of deforestation on the tropical rainforest water cycle? EVAPOTRANSPIRATION

Rainforests act as a storage for water for example through interception, surface storage in puddies, soil water and water in plant tissue. Therefore if rainforests were lost, storage of water would be removed, as the flow of water won't be intercepted and slowed, resulting in a high infiltration rate. This could cause flooding, particularly when the soil becomes waterlogged.

What would be the implications for the water cycle and the hydrosphere if rainforests were lost?

Over past 2 decades trees have been dying at an increasing rate and the rate of tree growth has remained flat. As a result, the average hectare of Amazon rainforest gains less than 1 ton of biomass/year. This is due to the paradoxical effect of the higher concentration of CO2 in air, encouraging tree growth, causing them to die faster (positive feedback mechanism). Faster growing trees invest less energy in defences against disease and produce less dense wood, therefore they are more susceptible to sickness or falling down. If sustained over a long time, increases in tree mortality could lead to degradation of the forest. Amazon's role as a global carbon sink is shrinking, we can't rely on trees to solve the whole carbon problem, deeper cuts in emissions will be required to stabilise our climate.

Why is the Amazon rainforest losing its ability to soak up CO2?


Ensembles d'études connexes

HESI 799 RN Exit Exam-w/ rationales

View Set

HESI RN Congenital Heart Disease - Peds

View Set

Chapter 9.2 Process of Cellular Respiration-GLYCOLYSIS

View Set

Quiz Bowl Literature Practice (writers)

View Set