geog notes.pdf

How are forests used by ppl? 1. Source of Raw Material - Tropical Rainforests(TR) are known for being valuable source of wood(building/carpentry) - Typed: teak,mahogany,rosewood(considered good wood bc of their strength,durability,colour) - Wood frm mangroves can be used t...

How are forests used by ppl? 1. Source of Raw Material - Tropical Rainforests(TR) are known for being valuable source of wood(building/carpentry) - Typed: teak,mahogany,rosewood(considered good wood bc of their strength,durability,colour) - Wood frm mangroves can be used to build hses, jetties,boats or as fuel, charcoal - Metals & minerals can be found beneath TR (diamonds/iron) → by mining: TR is cleared (burning/bulldozing) & heavy machinery is used to dig into the ground to extract the raw materials 2. Place of Habitation - Indigenous ppl(IP) depend on TR for food,water,shelter& clothing → they hunt for fish in mangroves,trade fish for rice → use mangroves as construction material to build traditional houseboats/ temporary huts(like the Moken ppl) 3. Place for Recreation - Ppl getting close to nature (by trekking,camping,bird watching) - Visiting forests has a positive impact on ppl’s health - TR have a calming effect on ppl(gives them a sense of well-being) 4. Source of Food - Many common types of food come from TRs(bananas,mangoes,vegetables) - Ppl hunt wild animals(like fish,deer,wild birds) → this is not sufficient in more developed societies →So mangroves hv been converted into farms(aquaculture) Consequences of Extracting Resources frm TR 1. Deforestation - Is the permanent removal of TR(unsustainable cuttting down of trees) - Human activities(like mining,agriculture,aquaculture) contribute to deforestation - TR vegetation is prevented from regenerating as cleared land wld be converted into site for human activities by humans  - (it takes as long as 1000 yrs for biodiversity to be re-established in TR 2. Environmental Impact a) Enhanced greenhouse effect - Carbon dioxide, nitrous oxide, methane can trap heat → this helps to keep Earth’s avg temp 15C and not -18C - TRs prevent build-up of carbon dioxide in the atmosphere(through photosyntheis) - burning/cutting down of trees cause carbon stored in the plant and soil to be released →fewer plants are left to absorb the increased amt of carbon dioxide( enhanced greenhouse effect) b) Loss of Biodiversity - Human activities destroys habitats of plants and animals → Many of these species are only found in specific areas so destruction can lead to extinction - Forested areas are broken into smaller patches( species that need large,connected habitats struggle to survive) → reduces genetic diversity & weakens ecosystem - Removal of certain species can disrupt food web & ecological balance (further biodiversity loss) c) Loss of Catchment Areas - TRs play a critical role in regulating water cycle → trees absorb & store water so when trees are lost, this natural catchment function is lost ( decreased water availability in surrounding area) - Loss of trees = in less moisture being recycled into atmosphere → contributing to reduced rainfall in the region (leads to more often and severe droughts) d) Increased Risk of Flooding, Soil Erosion & Sedimentation - Flooding: TRs help absorb rainfall & slow down water runoff so when they are cleared, there is nothing to absorb this water ( increased surface runoff & a higher risk of flooding in downstream areas - Soil Erosin: Roots of TR stabilises the soil so when the trees are removed, the soil becomes loose & more likely to erosion - Sedimentation: Erosion caused by deforestation leads to large amts of soil being washed into rivers & lakes, increasing sediment lvls. This can decrease water quality, disrupt aquatic habitats & reduce capacity of water bodies  Economic Impact: Depletion of Natural Resources - Extracting resources ( such as timber, mineral, oil) frm TRs provides immediate economic benefits through sale but unsustainable human activities can lead to resource depletion( harms economy in long run) - TRs provide valuable ecosystem services ( water purification, climate regulation, pollination) which support agriculture & other industries → When forests are destroyed, loss of these services result in an economic cost for local & national economies ( reduced agricultural productivity/ water treatment costs) - TRs are an important for ecotourism ( major souce of income for tropical countries) so when TRs are destroyed, the national beauty and biodiversity that attract ppl are lost (decrease in in tourism revenue) Social Impact: Effects on Indigenous Ppl (IP) - IP who live in TRs are often forcibly displaced from their ancestral lands (make way for logging,mining,agriculture) → deprives them of their homes and means of subsistence(food,medicine,shelter) - Destruction of rainforest disrupts the traditional ways of the lives of IP as their environment is altered/destroyed → their cultural practises & knowledge which are closely tied to the forest ecosystem, are at risk of being lost How can TRs be Managed Sustainably 1. Establish Protected Areas(PA) - Governments put lwas in place to ensure that ppl do not damage the PAs (illegally cutting trees/poaching exotic animals) → Ppl who break these lwas are heavily fined/ sent to jail - Effectiveness: depends on strong enforcement of these laws (a challenge in less developed countries due to lack of funding) 2. Regulate Forestry Activities - Difficult for the governments to set ALL TRs as PA →TRs ahv high economic value of resource extraction activities (provide many ppl e jobs & enable the country to earn money frm selling overseas) - Careful regulation is a way to strike balance between economic benefits from TR & conserving them  - The Brazil government works w certain logging companies to allow controlled logging in parts of Amazon Rainforest. Meaning, only specific trees are cut down & they are replanted afterwards to ensure the forests can recover 3. Rehabilitate Disturbed Aread of TR - Biodiversity if deforested aread is lesser compared to original TR - Forest rehabilitation aims to re-introduce at least some of plant & animal species which were originally found there →sometimes tree species which are not native to the area may be planted (they grow easily & quickly) - In Trombetas, northern brazil, large areas of TR that were deforested for mining have been rehabilitated since the 1980s 4. Promote Public Education - If ppl know TR importance & understand why they are under threat, they will more likely play a part → may decide to buy only wood products which are sourced frm sustainability managed forests/ recycle waste paper - TRs are a popular tourist attraction → They helpt to attract many foreign tourists →The income frm tourism will encourage governments to conserve the forests so more tourists wld visit - Costa Rica is famous for its TRs & many tourist come to visit to see the wildlife