Forestry is a profession that integrates science, art, and practice.
It involves creating, managing, using, and conserving forests and associated resources.
It aims for human benefit in a sustainable manner to meet desired goals, needs, and values, while protecting forests from harm or destruction.
Forestry balances the needs of the environment, wildlife, and forest communities.
It supports decent incomes while conserving forests for future generations.
Why Conserve Forests?
Sinks of Carbon Dioxide: Forests absorb and store carbon. In 2015, the world's forests stored 296 Gt of carbon in above and below ground biomass.
Habitats for Biodiversity Conservation: Forest areas designated for biodiversity conservation have increased since 1990. 524 million ha were forest within protected areas, and 651 million ha were designated for conservation of biodiversity in 2015.
Providers of Important Environmental Services: Forests managed for clean water supply, disaster resilience, recreation, and cultural/spiritual activities have increased since 1990. 1015 million ha were designated for protection of soil and water, and 1163 million ha for carbon storage and other cultural, spiritual, and ecosystem services in 2015.
Sustaining Livelihood and Economic Opportunities: Forests supply wood and non-wood forest products. In low-income countries, woodfuel is still the most important wood product.
In 2011, woodfuel accounted for 83% of total wood removals in low-income countries, versus 7% in high-income countries.
Industrial roundwood accounted for 17% of total wood removals in low-income countries, versus 93% in high-income countries.
Drivers of Forest Loss
Demand for agricultural land and fuel increases forest loss.
It's important to regrow more forests than are lost, including restoration and forest plantations.
Deforestation
Definition: Complete removal of trees for conversion of forest to another land use, such as agriculture, mining, or urbanization.
Results in a permanent conversion of forest into an alternative land use, with no expectation of regrowth.
Commodity-driven deforestation: Conversion of forests to agriculture (including oil palm and cattle ranching), mining, or energy infrastructure.
Urbanization: Conversion of forests to towns, cities, and urban infrastructure.
Shifting agriculture: Small-scale clearance of forest for subsistence, slash-and-burn farming.
Forest Degradation
Definition: Thinning of the canopy - a reduction in the density of trees in the area - but without a change in land use.
Changes are often temporary, with the expectation that the forest will regrow.
Forestry products: Logging and management of forests for products like timber, paper, and pulp.
Wildfires: Natural fires, or management through deliberate burning.
Deforestation vs. Forest Degradation
Forest loss is the combination of deforestation and forest degradation.
Deforestation: Abrupt transition from land with trees to land without trees, with no subsequent regrowth.
Forest degradation: Thinning of the canopy and loss of carbon without a change in land use. Forest is expected to regrow.
Annual Tree Loss: 20.93 Mha
27% is permanent deforestation, primarily in tropical regions.
73% is forest degradation.
Deforestation
95% of global deforestation is for agriculture.
Mostly (>70%) from agriculture. Includes mining & urbanization.
Net gain and net loss are mapped globally, with areas of small change and no data also indicated.
Global Forest Resources Assessment 2015 (FRA)
Forest areas have decreased since 1990, but the rate of net forest loss has been cut by 50%.
World's forest annual net loss:
1990-2000: 7.3 Million ha / year
2000-2010: 3.3 Million ha / year
2010-2015: NO Million ha / year (Actual net gain of 54 Thousand ha/year)
Net forest increases have been mostly in temperate and boreal zones.
The largest forest loss has occurred in the tropics, particularly in Africa and South America.
What do forests look like?
The share of planted forest is increasing.
Global forest area, 2015: Natural forest area (93%), Planted forest area (7%)
Planted Forests:
1990: 6%
2005: 7%
2015: 7%
Remaining Challenges
The extent of the world's forest continues to decline as human populations grow and demand for food and land increases.
Governments, private companies, communities, civil society, and international organizations must adopt policies and invest in sustainable forest management.
Forests should be regarded as an integral part of the rural space, providing global public goods and services to current and future generations.
1990: 0.8 ha per person
2015: 0.6 ha per person
Forest Cover Tied to Population Growth
Mauritius case study shows a decline in native forest cover with increasing population.
Major regional ecological community of plants and animals based on predominant plant form and structure (physiognomy).
Tropical forest
Temperate forest
Boreal forest
Tropical savanna
Temperate grasslands
Mediterranean shrub (chaparral)
Tundra
Desert
Biomes distribution across the globe including Nearctic, Palearctic, Afrotropic, Neotropic, Antarctic, Indo-Malay, Oceania, Australasia regions.
Tropical and subtropical moist broadleaf forests
Tropical and subtropical dry broadleaf forests
Tropical and subtropical coniferous forests
Temperate broadleaf and mixed forests
Temperate coniferous forests
Boreal forests/taiga
Tropical and subtropical grasslands, savannas, and shrublands
Temperate grasslands, savannas, and shrublands
Flooded grasslands and savannas
Montane grasslands and shrublands
Tundra
Mediterranean forests, woodlands, and scrub
Deserts and xeric shrublands
Mangroves
Biome Distribution
Biomes are distributed along climatic axes of temperature and precipitation.
Weather vs. Climate
"Weather is what you get; Climate is what you expect."
Weather: Short-term atmospheric conditions (temperature, humidity, precipitation, wind, cloud cover, etc.) at a particular place.
Climate: A statistical description of the mean and variability of the weather over a period ranging from months to thousands or millions of years.
The typical period is 30 years, as defined by the World Meteorological Organization (WMO).
Climate Variability and Climate Change
Climate variability: The way climate fluctuates yearly above or below a long-term average value (e.g., varying annual precipitation or winter temperatures).
Climate change: Long-term continuous change (increase or decrease) to average weather conditions or the range of weather (over many decades).
Factors Influencing Climate
Examples include thunderstorm cold fronts, El Niño and La Niña events, volcanic eruptions, solar flares, changes in Earth’s orbit (glacial advance/retreat), and changes in greenhouse gases.
Biome Distribution and Climate Factors
Biomes are distributed along axes of temperature and precipitation
Precipitation influences the presence of:
Evergreen-broadleaf trees
Drought deciduous trees
Shrubs and grasses
Arid shrublands and desert
Temperature influences the presence of:
Evergreen-broadleaf trees
Winter deciduous (temperate & wet)
Grasses (temperate & dry)
Needle-leaf trees
Shrubs and sedges
Biome Distribution Chart
The chart shows the relationship between mean annual precipitation (cm) and mean annual temperature (°C) for various biomes.
Biomes are arranged along a gradient from Tropical to Alpine environments.