Biological Valuation Map• Short presentation of the Biological

Valuation Map

• Evaluation criteria

• A few lessons from the BVM

• BVM and international instruments

Desiré Paelinckx – Hans Bosch – Peter Adriaens

What is the BVM ?

• A uniform survey of land cover and a biological evaluation of the Flemish Region

• An ecological description of the Flemish Region

A fixed set of legend units for:

• land cover (woods, arable land, pasture, urban areas….)

• vegetation(wet grassland, wet heath.…)

• landscape elements(tree rows, ponds, sunken roads.…)

What is the BVM ?

BVM version 2

field survey

Data from literary study:- municipal nature development schemes- land consolidation studies- scientific journals- ...

Digital data:- topographical map NGI- aerial photos OC-Gis Vl.- soil map NGI- bvm version 1- thematic studies- species databases-...

External data:- nature societies - nature reserve managers- foresters- volunteers-...

BVM versions

• 1978 - 1996: BVM, version 1

Global landscape ecological situation

• 1997 - 2006: BVM, version 2

More accurate and detailed instrument that can be used at parcel level

Biological Valuation Map• Short presentation of the Biological

Valuation Map

• Evaluation criteria

• A few lessons from the BVM

• BVM and international instruments

best professional judgements, with the following criteria:

• Rareness of the habitat• General biological quality

– flora (and fauna) diversity– Potential occurrence of rare flora (and fauna) – Importance of the habitat as a refuge for species

• Global vulnerability to overfertilization, acidification,....

• Replaceability: time required to create the habitat and to evolve to a certain “ecological balance”

Evaluation criteria

Evaluation:each habitat has its own fixed valuation• Mixed valuations for complexes. E.g. hp*

(w) + kn (z) becomes: (wz)

• With well-reasoned arguments it is allowed to deviate from these fixed valuations

• biologically – very valuable (z)– valuable (w)– less valuable (m)

• mixed valuations : – mw– wz – mz– mwz

• red shading : important fauna elements

Shading because of fauna

Fauna:Fauna (red shading), systematic method, good frame of reference

• Red List species of mammals, breeding birds, amphibia and reptiles, fishes, dragonflies and butterflies

• Wintering waterfowl: 5% standardSpined loach

BadgerWater railgadwalls, wigeons etc

Biological Valuation Map• Short presentation of the Biological

Valuation Map

• Evaluation criteria

• A few lessons from the BVM

• BVM and international instruments

The purpose requires a verystrict method

What is the target exactly?

What is the best method for gathering information?

How to process, interpret, and present data?

What basic informationmust be gathered?

Outlining the different steps accurately

Shortcomings of the BVM version 1

Problems with the BVM originate from

• uncertainties in legend units

• uniform mapping remains a critical issue several joint excursions per year

• evaluation

• period of time

Shortcomings of the BVM

• lack of description of the horizontal relations between units and areas

• lack of a clear connection between the abiotic environment and the mapping units

Ecological relations or vulnerabilities cannot be inferred directly

Time frame: crucial for grasslands and forests with springtime flora

if the mapping units become more detailed but the survey cannot be performed in an optimal fashion (e.g. at the right moment), the accuracy that seems to be created is misleading

detail mapping / scale mapping / period and time available

balance

Biological Valuation Map• Short presentation of the Biological

Valuation Map

• Evaluation criteria

• A few lessons from the BVM

• BVM and international instruments

BVM & Natura2000

• Ideal for defining and making a first assessment of habitat types

• Difficulties:– Restrictions typical of the BVM– Restrictions typical of the conversion of the

BVM into habitats

• Restrictions typical of the conversion of the BVM into habitats– A number of BVM mapping units are used both for

habitat and non-habitat possible habitat – A number of BVM mapping units are used for different

habitats habitat 1, habitat 2, …– Some habitats cannot be inferred from the BVM

not in the derived database– Others are difficult to infer as they are only a minor

part of the mapping unit they belong to habitat to be checked

Manual checking of the automatic conversion of existing BVM

geen habitat

31XXC

31XXC

4010;7150;6230;7140

4010C,31XXC

geen habitat

31XXC,4010C

geen habitat

4010C

4010;7150;6230;7140

31XXC

91D0

2310

m4010C,m31XXC

Vallei kleine nete.shpte controleren habitatgeen habitathabitatmogelijk habitatxzbdeels habitatNo Data

geen habitat

4010;7150;6230;7140

m3110;m3130;m3140;m7140;m7150

geen habitat

geen habitat

2310;4030;5130

Habbwk_nrp_ant.shphmhzbcghonbekend

Habitat key for Flanders

• What: further development of habitat sheets for field surveys, with clearer demarcation of habitat, less-developed habitat (new in 2004), and absence of habitat

• Target: identifying the correct N2000 habitat type and estimating its percentage in the field during BVM mapping