Enrichment of nature
All in all the shift towards a nature oriented farm will result in a better situation for the flora and fauna in the area. The number of species will grow. On the one hand this is caused by the construction of a number of new, indigenous landscape elements, and on the other hand because of the lower levels of nutrients used and the harvesting of for example shore vegetation and mud to be used as an input for farm management. Therefore on the whole, the soil on which the farming takes place will grow poorer.
There already are some nature friendly shores along the main watercourses. There will also be various nature friendly shores constructed in 2009. Ditch crossings will be adapted for fish and amphibians. Shallow shorelines will be combined here with deep overwintering places for fish. In the shallow zones young fish can grow up and when the zones become more densely overgrown they will be suitable for amphibians as well, such as green frogs and the small water salamander. Along the church path a cane filter was constructed which purifies the water. There will be another cane filter constructed in the polder in 2009. Furthermore there will be another mud flat and another walking path, partly in the shape of a corduroy path.
One sounding area with a flexible level
The current fragmented water levels due to the weirs will be replaced by one level in the Polder van Biesland. Because the ground level varies 60 cm in height, there will be differences with respect to the available dry soil profile. In the southeast of the Polder van Biesland the difference between water table and ground level will only be a matter of a few decimetres; on the higher, more productive grounds it could go up to 80cm.
The difference between (the now still) higher summer level and the winter level will be neutralized; in due time there will be a medium level, adjusted to the former summer level. Moreover a flexible level is foreseen along with this medium level, with a water level in the ditches that will fluctuate above the medium level (about 15cm) in winter and below the medium level in summer. This fluctuation is of big importance to the shore vegetation to come to full growth and to maintain its vitality (also in relation with the shore erosion). In case of a lower level in summer more shore plants run the risk of germinating in dry places, whereas, in case of a higher level in autumn and winter, humus of withered plants is transported elsewhere, so that the vegetation does not choke and roughen. Vital shore vegetation is of major importance to the fauna and for securing the shores.
Opportunities for animals
By bringing more natural elements into the area it is made sure that the fauna species can stay in the area. Nature friendly shores and little corners will make sure that for example different separate biotopes come into being, in which animals can take shelter, eat, and reproduce, etc. It also offers animal species that do not live in the polder year-round the chance to settle temporarily or to rest. One can think of overwintering- or migrating birds or summer guests like the stork.
The wettest areas of extensive meadowland offer opportunities to very critical meadow birds like the common snipe. On the grain fields the settlement of the yellow wagtail, the field lark and the partridge is to be expected. The still to be constructed nature friendly shores are of great importance to dragonflies, amphibians, breeding birds (ducks, reed buntings and sedge warblers), and foraging marsh birds (stork and spoonbill). The widening of the ditches is of advantage to the spoonbill, the great crested grebe and diving ducks. For diving ducks the deepening of the ditches is also of importance, as well as for the fish as it offers better chances of surviving winter. The new edge of the wood offers a variety of opportunities to bush birds, like the marsh warbler, the whitethroat and the icterine warbler, and mammals, like bats, mustelids and mice, as well as insects, like butterflies.
More plant species
The botanic quality of the grasslands will increase even more. Especially on the, still to be, extensified grasslands and the nature friendly shores flowery meadowlands will come into being with marsh-marigolds, real ragged robins, St. John's worts and geniculated foxtail. On the other meadowlands, that are only fertilised moderately, an increase in the number of species is to be expected as well. Because of the fact that the borders of the parcels (along the ditches) are not fertilised anymore, rich vegetation types will come into being here. The gradual process of the soil becoming poorer takes some time. Because of the big number of plant species the grasslands will offer a colourful view most time of the year.
On the mud flats a permanent pioneer vegetation is to be expected, that can survive because of the fact that the mud is under water most of the time during winter. On grain fields, meadow weeds will settle. These are weeds that represent the Dutch national flag: red (poppy), white (real camomile) and blue (cornflower).
The following fauna groups are monitored in Biesland every year: day butterflies, dragonflies, bats and (meadow)birds. Apart from that a survey of the vegetation was made in 2006. A summary of the results is found in the book <em>Verhalen van Biesland 2006</em> (Stories of Biesland). A big scale fish examination was carried out in 2007 and 2008. For plants as well as fish this will be carried out every five years to monitor the changes. The results will be recorded every year in Verhalen van Biesland.