Basic Natural Stock includes areas (in a variety of open space uses) which may have their own, more local ecological interest or landscape value, or may contribute to the interlinking of wildlife habitats or the integrity of valued landscape features (e.g. land alongside railways and watercourses).
It is important that most of the land identified as Basic Natural Stock remains as open space. There may be exceptional instances when development for other purposes can be permitted if:

•    it involves only a small proportion of a particular site and, where necessary includes measures to ensure that the development does not significantly detract from its ecological or landscape value, or;
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•    the ecological or landscape contribution of the site which is proposed for development can be satisfactorily compensated for by, for example, the upgrading of land of lower ecological or landscape value within or adjoining the site, or elsewhere in the City.

The Proposals Map in the Local Plan identifies the main components of what is currently regarded as Lincoln's Basic Natural Stock, and the sites are described in Appendix C Schedule 2. of the Local Plan. However, it is not possible to identify every small area of open space which is of local value and there may, therefore, be occasions when the City Council will require other sites to be afforded similar protection.
Although the areas identified as Critical Natural Assets are individually considered to be of crucial importance to the landscape and nature conservation characteristics of the City, they do not include every feature that is of local ecological or landscape importance, e.g. Several of the strips of open land, trees and other planting alongside main approaches to the City (main roads, railways and waterways) fall into the category of Basic Natural Stock, chiefly because of their landscape contribution (although the ones which contribute most to the setting of the City as a whole are classed as Critical Natural Assets).
From a nature conservation point of view, protecting critical habitats is important, but the natural environment would quickly lose its vitality and viability if these sites were the only ones retained as natural or semi-natural areas. They would become isolated and unsustainable, without the support of Basic Natural Stock linking them to each other and the open countryside.

In the case of landscape quality, there are many open areas which might be lost to development without harming the landscape setting of the City when viewed from afar, but which are of immense value to the
identity and environmental quality of local areas and are greatly cherished by local people.

When, exceptionally, development of a type which is not ancillary to an open space use is considered to be acceptable within a Basic Natural Stock site, developers may be required to enter into a legal obligation to ensure that an agreed enhancement or compensatory scheme is implemented.