The last century has seen massive tree loss world-wide as a result of human activity. Despite many industrialised nations recently halting or reversing the trend in their own countries, their demand for timber, pulp, and land has remained and so global deforestation continues. Concern is growing over the loss of biodiversity, soil erosion, flooding, and climate change. The role of deforestation in these problems is clear and reforestation is seen as an essential part of any possible solutions. Of course planting trees is not enough, steps must also be taken to end the world-wide destruction of exisiting wildlife habitats and put survival and quality of life before greed and profits.
1. For wildlife and conservation
Most of this country's flora and fauna has evolved in woodlands and remains dependent on trees, shrubs and the associated habitats. Our native trees support a huge biodiversity, the oak for example supports over 240 moths and butterflies. There is a complex web of interaction and dependance between species and loss of any one species can have a knock on effect through-out the entire eco-system. Newly planted native woodland will take centuries before it replicates natural woodland. However it is better than nothing and does provide some habitat for our native wildlife. Where possible, natural regeneration can provide a more natural and diverse habitat than tree planting.
2. Timber and pulp production
Imports acount for 90% of this country's timber use. While only 10% of that is hardwood, most of that is extracted unsustainably from tropical countries. While sustainably managed native woodlands in the UK could meet some of our current timber demand, it is forecast that demand will double over the next 60 years. We could not meet such demands even if the entire country was planted with conifer plantations! Tree planting, while useful, is not enough. Clearly we need to address our wasteful consumption patterns; recycle more, use less - packaging, newspapers etc.
3. To counter global warming
Trees use carbon dioxide to grow. The carbon dioxide is held within the trees structure and remains there until the tree decays or is burnt. Human activities such as destroying rainforests and burning fossil fuels are releasing massive quantities of carbon dioxide into the atmosphere and increasing the heating of the planet which is caused by the 'greenhouse effect'. Planting more trees will help to offset human carbon dioxide emissions but is not a solution to global warming. Emissions of all greenhouse gases resulting from human activity need to be cut at source and the world's remaining forests protected from further unsustainable exploitation.
4. To improve air quality
Trees measurably reduce air pollutants such as sulphur dioxide and lead from industrial and vehical emissions. Trees even remove dust from the atmosphere by filtering and traping it on the leaves to be washed away by rain and returned to the soil. In streets without trees the amount of dust can be four times higher than those with trees. During photosynthesis, trees give off oxygen. The daily oxygen requirement of ten people can be met by a single mature beech tree but it would require 2,700 saplings to do the same.
5. To reduce flooding and soil erosion
In woodland, about 85% of rainwater is absorbed and release slowly over a period of time. This sponge effect helps to reduce surface water run-off and avoid flooding. The tree canopy provides shelter and reduces the impact of the falling rain and the roots help to prevent the soil from being washed away. Soil erosion leads to the pollution of lakes and rivers. Top soil is the fertile and productive top few inches of soil and is a valuable resource, without it little can grow. Leaf litter from trees and other plants help create top soil.
6. As wind breaks and shelter
For centuries belts of trees and hedges have been planted as windbreaks by farmers protecting their crops and providing shelter for domesticated animals. Energy savings of up to 25% have been made on winter fuel bills by planting shelter belts around buildings. Trees also absorb moisture. Trees planted in belts around and within built up areas can cool the air and moderate temperature changes.
7. To reduce noise
Modern life is nosiy. Road traffic and engine noise can be diffused by trees and other plants. The energy of the sounds are partly absorbed by the flexible leaves and deflected by branches and trunks. A belt of trees 30 metres wide can reduce noise levels by 21 decibels (which is apparently quite a lot). Additionally, trees provide a visual barrier to hide or reduce the visual impact of human development.
8. Quality of life for people
Humans are native to the natural environment - not concrete cities and tarmac roads. Trees and woodlands provide a link to our common past. They remind us of our place in an eco-system that is essential to our survival. Public access to woodlands for recreation provide places where people can relax and regenerate away from the stresses of modern life.
See also: Tree loss in the UK, Global warming, Why burn wood?
