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Forests regulate the amount of water on the ground • The litter layer under the canopy play a role as insulation porous, forest ground cover to reduce evaporation and increase soil moist[r]
(1)Seminar Topic FORESTS 9.5 đ Instructor: DOCTORATE NGUYỄN VĂN MINH Group 4: Đỗ Văn Tình Võ Minh Tiến Châu Vũ Linh Nguyễn Thị Ngọc Dung (2) Vacabulary (3) I The Context • Forests cover a third of our planet's land • They provide raw materials, maintain biodiversity, protect land and water resources, and play a role in climate change mitigation (4) II Some of the main ecological benefit of forests Forests reduce erosion • The roots of rainforest trees and vegetation help anchor the soil When trees are cut down there is no longer anything to protect the ground, and soils are quickly washed away with rain The process of washing away of soil is known as erosion • As soil is washed down into rivers it causes problems for fish and people (5) The roots of rainforest trees and vegetation help anchor the soil (6) • On steep hillsides, loss of forest can trigger landslides Forests also play an important role in reducing damage from flooding by reducing the rate of water runoff In areas where bare soil, rain water falling water flow in soil erosion (7) Influence of forests on climate • Forests have a direct impact on the local wind regime • Wind regime change will lead to changes about moisture and temperature regimes • Forests are obstacles on the movement of the wind, the wind speed and wind direction changes • Forest changes in wind speed around the forest in a certain range in the catch wind and lee • sphere of influence of forest to the wind depends on the height of the forest • The higher the incidence of forest of larger forest to the wind • Effects of forest to wind depends on the structure of the forest Forest has a layered structure, the greater the influence of the forest to wind (8) Ành hưởng rừng đến gió là sở lý luận để xây dựng nên giải rừng phòng hộ Effects of forest to wind is the theoretical basis to build the forest Windbreaks are single or multiple rows of trees planted on windward field boundaries Windbreaks slow wind, reducing physical damage to crop's and fruit trees Placed on the windward side of atolls, they can also prevent salt-spray from reaching the interior and reduce coastal erosion Chắn gió là nhiều các hàng cây trồng trên ranh giới lĩnh vực đầu gió Chắn gió chậm gió, giảm thiệt hại vật chất cây trồng và cây ăn quả.Được đặt phía bên gió các đảo san hô, họ có thể ngăn chặn muối phun đến nội thất và giảm xói mòn bờ biển (9) Ứng dụng nông nghiệp Applications in agriculture Chắn gió là trồng tuyến tính cây và bụi cây thiết kế để tăng cường sản xuất cây trồng, bảo vệ người và vật nuôi, và mang lại lợi ích bảo tồn đất và nước Có nhiều loại khác chắn gió Lĩnh vực chắn gió bảo vệ loạt các loại cây trồng nhạy cảm với gió, gió kiểm soát xói mòn, và thụ phấn ong gia tăng và hiệu thuốc bảo vệ thực vật Chăn nuôi chắn gió giúp giảm căng thẳng động vật và tỷ lệ tử vong, giảm mức tiêu thụ thức ăn chăn nuôi, và giúp giảm tác động thị giác và mùi hôi Snowfences sống tiếp tục đường trôi tuyết và tăng lái xe an toàn Họ có thể lây lan tuyết qua cánh đồng, tăng độ ẩm đất mùa xuân Windbreaks are linear plantings of trees and shrubs designed to enhance crop production, protect people and livestock, and benefit soil and water conservation There are several types of windbreaks Field windbreaks protect a variety of wind-sensitive crops, control wind erosion, and increase bee pollination and pesticide effectiveness Livestock windbreaks help reduce animal stress and mortality, reduce feed consumption, and help reduce visual impacts and odors Living snowfences keep roads clean of drifting snow and increase driving safety They can also spread snow evenly across a field, increasing spring soil moisture (10) Forests help maintain the water cycle The role of forests in the water cycle is to add water to the atmosphere through the process of transpiration (in which plants release water from their leaves during photosynthesis) This moisture contributes to the formation of rain clouds, which release the water back onto the forest When forests are cut down, less moisture goes into the atmosphere and rainfall declines, sometimes leading to drought (11) (12) Forests regulate the amount of water on the ground • The litter layer under the canopy play a role as insulation porous, forest ground cover to reduce evaporation and increase soil moisture • Rainwater falling on the forest tree canopy and litter to keep the rate at which water flows more slowly Therefore, Forest restricts flooding (13) Forests for the atmosphere • Forests involved in the concentration of oxygen and carbon dioxide balance of the atmosphere • Forests affect water evaporation intensity of the surrounding environment, effective climate control, beneficial to plants • Forests against wind storm, dust filter of the atmosphere • Forests filter for fresh air, prevent dust, limited bacteria, pathogenic viruses (14) The role of forests for land • There is an important role in the formation of soil protection: erosion control soil, especially erosion on slopes slopes (15) Forests are valuable genetic resources • Forests are valuable genetic resource bank of humanity • There are approximately 10,000 species of higher plants (1000 species of large trees, 280 species of mammals, over 1020 species of birds, 259 species of reptiles, 82 species of amphibians, thousands of species of insects and other creatures) (16) III The status of exploitation of forest resources in the world Previously forests occupy about 60 million km ², and in 1958 only 44.05 million km ² in 1973 to 37.37 million km ² Current forest area is declining due to human impact and only about 29 million km (17) • Since 1950 approximately 50% of tropical forests, • By the early '80s tropical forest loss in speed of 113,000 km ² / year • The rate of forest loss in recent years as increasing strength, predicted by 2020 about 40% of the remaining forest is destroyed seriously (18) IV The current situation of forest resources in Vietnam For many reasons such as the long-lasted war, shifting cultivation and over-exploitation, the forest area reduced at alarming rate (19) The reasons for forest lost A B Fosrest fire over-exploitation C long-lasted war shifting cualtivation D (20) • The War: From 1961 to 1975, 13 million tons of bombs and 72 million liters of toxic chemicals sprayed mainly in the south have destroyed about 4.5 million hectares of forest • The expansion of agricultural land: shifting cultivation has turned 13 million hectares of former forest land barren (21) In 1943, forest area of Vietnam is estimated at 14 million ha, with a coverage rate of 43% By 1976 the area dropped to 11 million hectares of forest cover rate 34% in 1985 to 9.3 million with coverage of 28%, in 1995 only million hectares forest area ratio coverage of 24.2% (Khoa hoc moi truong, Le Van Khoa) (22) Chart: Changes in forest area of Vietnam over the period (millions of hectares) 14 12 10 diện tích rừng tự nhiên 10.2 10.88 10 14 9.4 10.91 8.72 6.95 diện tích rừng trồng 0 1943 0.09 1976 0.58 1985 1.05 1995 1.6 2000 2.09 2003 2.5 2005 2.53 2009 (23) V HOW CAN FOREST AREA BE PRESERVED? To protect and develop forest resources in Vietnam, the State should apply the following policies: - Afforestation and greening of barren hills - Protected forests, national parks and nature reserves - Rational exploitation of forest production, limited clearing of forests to agricultural land, limiting migration - Natural closed forests (24) Forest protection measures Technical and economic measures Existing forest protection and afforestation: afforestation and greening of barren hills Mobilize people to participate in forest planting and protection Forest land planning and identify stable stand types of forest planning (protection, special use and production) Construction of national parks and nature conservation Legal measures Solve problems sedentary farming of ethnic minorities Closed forest, exploitation ban Forest protection legislation (Our country has introduced laws to protect forests in 2004) (25) Propaganda protect of forest (26) Currently, Vietnam has 27 national parks; Sanctuaries species / habitats; 18 landscape protection area; 27 nature reserves; 12 Nature Conservation Examples: CUC PHUONG National Park BACH MA National Park NAM CAT TIEN National Park …………… and Et cetera (27) CUC PHUONG National Park (28) VI HOW CAN THEY BE INCREASED? • Exploitation of natural resources, but still maintain the inherent ecological processes of the forest • Prevent deforestation, especially primary forests, tropical forests • Positive afforestation, intensive afforestation so that more forest exploitation • Strengthen propaganda about the role of forests • Build a system to protect natural (29) Forest will be increased by activity people (30) The afforestation (31) In addition Putting content protection and natural resources on education and the mass media Mobilization of ethnic minorities living sedentary, development of agro-forestry or forestry-fishery combination of eco-sustainable exploitation of forests Focusing on planning and management of protected forest (32) The question: Do you like the afforestation? Why or why not? Tell me some forest protection measures in your country you know? (33) THANK FOR LISTENING (34)