4.1.2 Rationale
Open spaces valued for their wildlife, landscape or recreational contributions have to be protected, managed and sometimes improved if their value to current and future generations is not to be reduced.
To protect Lincoln's special identity, it is important that new developments do not harm the City's landscape characteristics and wildlife, but complement them - adding to local distinctiveness rather than diluting it;
    • Natural and man-made features which local people value should not be swept away, distorted or degraded simply because their contribution to local distinctiveness - has not been identified. Particular features may be of even greater value - national or international - and this also needs to be taken into account when decisions are being made.
    • Although Lincolnshire contains large areas of open space - mostly farmland - Lincoln itself is a tightly contained urban district within which the remaining open spaces are under increasing pressure, having to compete with other land use requirements (such as the need to satisfy housing and employment demands etc.). The importance of safeguarding areas of open countryside and productive agricultural land has meant that much of the land surrounding the City has been unavailable for housing and other development.
A "sustainable" city requires a wide range of easily accessible open spaces.
    • The need for more sustainable forms of development now requires further restraint of urban sprawl and dispersal, and redevelopment of previously developed sites, to reduce dereliction and make maximum use of the land which is available within the confines of existing urban areas. These considerations, if accepted in isolation from the other needs and demands of an urban community, would, in time, lead to a city consisting of virtually uninterrupted built development, which would be totally reliant upon the surrounding countryside for its open space needs. This would inevitably result in a very poor urban environment and intolerable pressure on the countryside. It would also have wider environmental impacts. For example, people would have to travel greater distances to reach open space for recreation; the likelihood of them using cars would increase and the associated pollution and consumption of fuel resources would grow. Some of the urban traffic congestion would probably simply be transferred to the countryside, rather than being reduced by changes in modes of travel. Taking the need for a more sustainable approach to development a stage further, the less attractive, accessible and diverse our urban spaces become, the greater the incentive for people to travel to sensitive countryside further afield to meet their recreational needs.

Nature gives pleasure, inspiration and an escape from the stresses of city living. It also makes a significant contribution to our health and well-being, both physically and mentally.
    • Plants can help to contain the effects of airborne pollution (for instance one urban tree can trap up to a tonne of dust) and ten minutes walking in the local nature area goes a long way to help relieve some of the stresses of modern day living. A surprising amount and diversity of wildlife has survived in the City. However, the fragmented nature of urban habitats leaves them very vulnerable. If a diversity of wildlife is to be enjoyed in the future, it is important that steps are taken now to ensure that this resource survives.

Trees, and plants in general, are essential to life. Vegetation absorbs carbon dioxide, storing carbon and releasing oxygen. One fully grown beech tree produces enough oxygen each year for ten people. It will also "clean" the air by consuming over 2 kg of carbon dioxide per hour. Carbon dioxide is the dominant "greenhouse" gas. While a level of "greenhouse" effect is necessary to sustain life, the build up of these gases due to man's activities now threatens the global environment. Increasing tree and plant cover is one of the more positive actions which can be taken to reduce the problem. The proposals in this Plan to plant woodlands and the policies to protect trees and require planting in connection with development schemes, have been included partly with those benefits in mind.

Sensitively positioned, trees and other planting also offer a range of local environmental benefits. They can:
•    help absorb gas emissions from vehicles;
•   reduce local pollution from airborne particles, such as lead;
•   act as sound barriers;
•   contribute to micro-climatic effects which reduce energy consumption;
•   offer shade from the sun (helping to counter the growing incidence of skin cancer);
•   contribute to traffic calming measures;
•    provide habitats for wildlife, an important reason for using local native species.
Research also indicates that trees and other planting in urban landscapes can have useful psychological effects,  helping to  reduce stress,  and  anti-social  behaviour and  promoting  an increased  sense of community responsibility and civic pride.