Favourable conservation Favourable conservation statusstatus – forest habitats – forest habitats

State Nature ConservancState Nature Conservancyy of the Slovak republic of the Slovak republic

Forest research instituteForest research institute

Forest managment planing instituteForest managment planing institute

EFRAEFRA

Approach chosen:Approach chosen:

Basic data on forest habitat for the respective siteBasic data on forest habitat for the respective site

AreaArea PresentPresent area of forest habitat for the area of forest habitat for the respective siterespective site; in SR; in SR PotentialPotential area of forest habitat (based area of forest habitat (based on site type units upon the on site type units upon the trtraansformation of site types into habitat nsformation of site types into habitat units)units)

RangeRange rangerange of forest habitat according to of forest habitat according to biogeographical region in SRbiogeographical region in SR

Criteria (FCS)Criteria (FCS) Indicators (FCS)Indicators (FCS)

aa Typical habitat speciesTypical habitat species Tree species compositionTree species composition (degree of (degree of approximation to the model and occurrence of approximation to the model and occurrence of invasive tree species)invasive tree species) Herb & shrub speciesHerb & shrub species

bb Forest habitat structureForest habitat structure Age structureAge structure (developmental stages of natural (developmental stages of natural forests or even-aged forests);forests or even-aged forests); Natural regenerationNatural regeneration Spatial structureSpatial structure (vertical, horizontal, structural (vertical, horizontal, structural pattern)pattern) large-diameter and biodiversity valuable treeslarge-diameter and biodiversity valuable trees large-diameter deadwoodlarge-diameter deadwood

cc Negative influences Negative influences Negative factors / agents Negative factors / agents Forest healthForest health (as a result of negative factors (as a result of negative factors impact)impact) Broader environmentBroader environment

DefinitionsDefinitions

• Clear definitions are needed for:Clear definitions are needed for:

1.1. Terms employedTerms employed (tree layer, growth class, (tree layer, growth class, natural regeneration, etc.) natural regeneration, etc.)

2.2. Quantifiers, measurement unitsQuantifiers, measurement units

3.3. Form of recordForm of record (e.g. using mathematical (e.g. using mathematical symbols, description, etc.)symbols, description, etc.)

Tree species compositionTree species composition

• Degree of approximation to the modelDegree of approximation to the model (%) given (%) given for each particular habitat, for each particular habitat, e.g. 9410: e.g. 9410: sprucespruce 50– 50–100, 100, sycamore maplesycamore maple 00–10, –10, sorbus aucupariasorbus aucuparia 00–50–50

• Occurrence of invasive tree speciesOccurrence of invasive tree species+ the least controversial indicatorthe least controversial indicator+ sufficient knowledge on the natural tree species sufficient knowledge on the natural tree species

compositioncomposition- complicated & unclear systemcomplicated & unclear system- weak argumentation on the approximation degrees weak argumentation on the approximation degrees

required (e.g. "what is the relevance of 30 %?")required (e.g. "what is the relevance of 30 %?")- inability to assess gene pool naturalnessinability to assess gene pool naturalness- inability to identify the tree species behind the changeinability to identify the tree species behind the change

Herb & shrub speciesHerb & shrub species• presence of a larger number of species, more presence of a larger number of species, more

complicated field assessmentcomplicated field assessment• extreme difficultness of exact investigationextreme difficultness of exact investigationSolution:Solution:1.1. Herb layer composition is determined by the Herb layer composition is determined by the

tree layertree layer2.2. Most significant changes are: onset of invasive Most significant changes are: onset of invasive

or expansive species, indicators of acidification or expansive species, indicators of acidification and eutrophication, ruderal species, etc.and eutrophication, ruderal species, etc.

3.3. simple list of herbs on sites with cover by simple list of herbs on sites with cover by Tansley scaleTansley scale

Herb & shrub species Herb & shrub species

+ Simple assessmentSimple assessment

+ Reflection of most distinct changes onlyReflection of most distinct changes only

- Inability to reflect reduction of biodiversity Inability to reflect reduction of biodiversity provided natural species are not replaced provided natural species are not replaced by the aforementioned speciesby the aforementioned species

- One-sided decision on the naturalness of One-sided decision on the naturalness of certain species (e.g. certain species (e.g. Urtica dioicaUrtica dioica))

SStructuretructure

• Ambiguity of the term "structure" Ambiguity of the term "structure" (arrangement of components / parts or (arrangement of components / parts or interactions /processes within any higher interactions /processes within any higher hierarchical unit)hierarchical unit)

• Our approach:Our approach: structure limited to spatial structure limited to spatial structure of forest habitats and their groups structure of forest habitats and their groups only (age structure, structural pattern)only (age structure, structural pattern)

• Unclear importance of spatial structure for Unclear importance of spatial structure for the assessment of FCSthe assessment of FCS

Spatial structure of forest Spatial structure of forest habitathabitats and / s and / or their groups:or their groups:

• Horizontal structure (Horizontal structure (sizesize and distribution of and distribution of structural units)structural units)

• vertical structure (multi-layeredness of forest vertical structure (multi-layeredness of forest stands) stands) ≈ function of tree age => age structure≈ function of tree age => age structure

1.1. Close affinity of both structures. Close affinity of both structures.

2.2. Vertical diversity of natural forests has in Vertical diversity of natural forests has in managed forests been to a certain degree managed forests been to a certain degree replaced by the mosaic of even-aged stands.replaced by the mosaic of even-aged stands.

Other indicators of structure criterion:Other indicators of structure criterion:

• natural regenerationnatural regeneration (principal precondition (principal precondition of forest stand sustainability; possible listing of forest stand sustainability; possible listing within the forest habitat species structure)within the forest habitat species structure)

• large-diameter and biodiversity valuable large-diameter and biodiversity valuable trees trees (for some type of habitats it is a good (for some type of habitats it is a good indicator of structure, if we do not have indicator of structure, if we do not have other structure indicatorsother structure indicators; need to assess ; need to assess them separatelythem separately; biodiversity valuable; biodiversity valuable))

• deadwooddeadwood (biodiversity valuable (biodiversity valuable;; in spatial in spatial structure serves only aesthetic purposes)structure serves only aesthetic purposes)

Key issues related to structure definitionKey issues related to structure definition

• Quantification of Quantification of minimal limit valuesminimal limit values for the for the assessment of growth class, developmental assessment of growth class, developmental stage, tree layer... stage, tree layer... 10%10%

• Quantification of the Quantification of the area limitarea limit for the layer unit for the layer unit and even-aged forest unit and even-aged forest unit (0,30 ha)(0,30 ha)

• Quantification of the minimal Quantification of the minimal stocking levelstocking level of the of the respective unit respective unit (0,(0,33))

Relation between natural regeneration and developmental stage Relation between natural regeneration and developmental stage of forest stand:of forest stand:

1.1. Conditions for natural regeneration match the developmental Conditions for natural regeneration match the developmental stage of particular forest stands stage of particular forest stands and / orand / or seedlings and seedlings and saplings cover 61 – 100 % of the area expected to be saplings cover 61 – 100 % of the area expected to be covered. covered.

2.2. Conditions for natural regeneration don’t match the Conditions for natural regeneration don’t match the developmental stage of particular forest stands completely developmental stage of particular forest stands completely (gaps in a canopy, lowered density of stands) (gaps in a canopy, lowered density of stands) and / orand / or seedlings and saplings cover seedlings and saplings cover 11 – 60 %11 – 60 % of the area expected of the area expected to be covered (including premature canopy gaps).to be covered (including premature canopy gaps).

3.3. Conditions for natural regeneration don’t match the Conditions for natural regeneration don’t match the developmental stage of particular forest stands completely developmental stage of particular forest stands completely (gaps in a canopy, lowered density of stands) (gaps in a canopy, lowered density of stands) and / orand / or seedlings and saplings cover seedlings and saplings cover 1 – 10 %1 – 10 % of the area expected of the area expected to be covered (including premature canopy gaps).to be covered (including premature canopy gaps).

4.4. Conditions for natural regeneration are not expected (site is Conditions for natural regeneration are not expected (site is covered only by overmature stands) or there are conditions covered only by overmature stands) or there are conditions for natural regeneration, but for some reason the trees are not for natural regeneration, but for some reason the trees are not fertile.fertile.

Large-diameter and biodiversity valuable Large-diameter and biodiversity valuable treestrees

• Quantification of the minimal diameter and Quantification of the minimal diameter and number of treesnumber of trees– absoluteabsolute diameter (>... cm) vs. diameter (>... cm) vs. relativerelative (one generation (one generation

older, older, ???? cm larger than main / final crop) cm larger than main / final crop)– prime difficulty: determination of a reasonable value of prime difficulty: determination of a reasonable value of

the above mentionedthe above mentioned• objective: objective: to ensure certain proportion of larger to ensure certain proportion of larger

trees also in younger even-aged forest standstrees also in younger even-aged forest standsDeadwoodDeadwood• Quantification of the minimal diameter, length and Quantification of the minimal diameter, length and

number of trunksnumber of trunks– diameter has to be diameter has to be an an absoluteabsolute value value

Negative influencesNegative influences

• negative agents / factors negative agents / factors – list only, no – list only, no impact on the overall FSCimpact on the overall FSC

• forest healthforest health – result of the combined – result of the combined influence of negative factors; indirect influence of negative factors; indirect assessment based on visible tree damageassessment based on visible tree damage

• broader environment impactbroader environment impact– size and isolation / fragmentation of the sitesize and isolation / fragmentation of the site– total length of border with "negative areas"total length of border with "negative areas"

Forest healthForest health1.1. Mild damageMild damage with no impact on tree physiological with no impact on tree physiological

processesprocesses

2.2. Medium damageMedium damage with short-term impact on tree with short-term impact on tree physiological processesphysiological processes

3.3. Significant damage Significant damage with long-term impact on tree with long-term impact on tree physiological processesphysiological processes

4.4. Fatal damageFatal damage resulting in dieback or causing resulting in dieback or causing dieback within 10 yearsdieback within 10 years

+ Due consideration for damage significanceDue consideration for damage significance- One-sided assessmentOne-sided assessment- No distinction between acute and chronic No distinction between acute and chronic

damagedamage

Size and isolation of the siteSize and isolation of the site• Minimal size of intact site Minimal size of intact site oror minimal minimal

total area of the site grouptotal area of the site group- Lack of objective criteria for the area Lack of objective criteria for the area

quantificationquantification

Contact with "negative areas" such as:Contact with "negative areas" such as:• Intensively managed agricultural landIntensively managed agricultural land• Active surface quarriesActive surface quarries• Growing areas ofGrowing areas of windfalls and other windfalls and other

damaged sitesdamaged sites- Ignorance of the interrelation between the site’s Ignorance of the interrelation between the site’s

size and the length of border with negative areassize and the length of border with negative areas

Assessment tables of particular habitatsAssessment tables of particular habitats

• Is it necessary to have a separated table for Is it necessary to have a separated table for each particular habitat?each particular habitat?

• What is the purpose of the tables?What is the purpose of the tables?– Tool for field officers?Tool for field officers?– Tool for software developers?Tool for software developers?

• Is the requirement for tables to be Is the requirement for tables to be "readable" or utmost brief?"readable" or utmost brief?

Differences between habitatsDifferences between habitats

• Large-scale vs. small-scale habitatsLarge-scale vs. small-scale habitats– possible problem while comparing countriespossible problem while comparing countries

• natural vs. natural vs. ± ± seminaturalseminatural habitats habitats– also among forest habitats we can find also among forest habitats we can find nonnon--

climaxclimax ones ones (for example 91N0 (for example 91N0*)*)• planar vs. linear habitatsplanar vs. linear habitats (9130 or 91E0(9130 or 91E0*)*)

• unique habitats vs. habitats similar to unique habitats vs. habitats similar to neighbouring onesneighbouring ones (for example in SR 91MO vs 91G0(for example in SR 91MO vs 91G0*)*)

• special case: special case: dwarf pinedwarf pine (which is non forest habitat, but (which is non forest habitat, but we assess dwarf pine as forestwe assess dwarf pine as forest))

Unforeseen problem: Unforeseen problem: what does habitat include?what does habitat include?• Commonly valid: unfavourable habitat Commonly valid: unfavourable habitat

status = different habitatstatus = different habitat (9130 (9130 »» 9110 9110))

• Indicators assessed depend on the site Indicators assessed depend on the site assessed.assessed.

Solution:Solution: habitat excludes: habitat excludes:1.1. Clearcuts or windfalls larger than 3 haClearcuts or windfalls larger than 3 ha2.2. Spruce, larch, etc. monocultures larger Spruce, larch, etc. monocultures larger

than 0,5 hathan 0,5 ha3.3. ......

Criteria / Indicator

Favourable status Unfavourable status

A B C D

excelent good reduced degraded

Typicalspecies

of habitat

Tree species composition

3. v.d.: Fagus sylvatica, Quercus petraea agg., Carpinus betulus, Acer pseudoplatanus, Acer platanoides, Tilia cordata, Tilia platyphylos, Cerasus avium4. v.d.: Fagus sylvatica, Abies alba, Acer pseudoplatanus, Acer platanoides, Tilia cordata, Tilia platyphylos, Cerasus avium5. and 6. v.d.: Fagus sylvatica, Abies alba, Picea abies, Acer pseudoplatanus, Acer platanoides, Ulmus glabra, Fraxinus excelsior, Sorbus aucuparia, Tilia cordata, Tilia platyphylos

- approximation to the model - %- occurence of invasive tree species - %

100 - 85 % and0

84 - 70 % and<1

69 -55 % and/or1-20

54 - 40 % and/or

20 - 40

Herb species and shrubs- indicators - %- invasive species %

< 5

0

(5 ; 25>

< 5

(25 ; 50)

(5 ; 25)

≥ 50

≥ 25

Indicators of eutrofization

Urtica dioica, Chelidonium majus, Sambucus nigra

Accidic indicators

Avenella flexuosa, Vaccinium myrtillus, acidic machy Pozn.: dominantný výskyt týchto druhov mení zaradenie lokality do biotopu

Habitat structure

Age structure (developmental developmental stages of natural stages of natural forests or even-forests or even-

aged forestsaged forests)

V polygóne prevažujú pralesy a prírodné lesy

V polygóne prevažujú 5. ARS[1] a 4. ARS alebo 5. ARS tvorí aspoň 1/3 ak sa jedná mozaiku aspoň dvoch ARS [1] ARS – agregovaný rastový stupeň (pozri Definície indikátorov FCS)

V polygóne prevažujú 3. ARS, 2. ARS a , 1. ARS, pričom 5. ARS nesmie presahovať 1/3. V prípade, že prevažuje 1.ARS, musí byť prítomný ešte aspoň jeden ďalší ARS

Prítomnosť len 1. ARS na celej ploche polygónu

Natural regeneration of the tree species

1 2 3 4

Spatial structure (vertical, horizontal, structural pattern)

≥ 50 % lokality je tvorených dvoj- a viacvrstvovými porastmi

≥ 50 % lokality je tvorených mozaikou jednovrstvových porastov, v ktorej výmera jedného štrukturálneho prvku je prevažne do 5 ha

≥ 50 % lokality je tvorených mozaikou jednovrstvových porastov, v ktorej výmera štrukturálneho prvku a je prevažne 5,01 - 50 ha

Large-diameter and  valuable trees

≥ 5 ks / ha

evenly

1 – 4 ks / ha

evenly

3 – 9 ks / 10 ha < 3 ks / 10 ha

Large-diameter deadwood

≥ 4 ks / ha

evenly,

diferent degree decomposition

2 – 3 ks / ha

evenly,

diferent degree decomposition

1 ks / ha < 1 ks / ha

Negative influences

Negative factors

imissions, nekrózy buka, pastures, zver (odhryz, obhryz), dry soil conditions, mechanical disturbance

Health status

0 - 5 % nad prirodzený výskyt

6 – 10 % nad prirodzený výskyt

11 % a viac nad prirodzený výskyt

bez obmedzenia

Broader environment-coverage of habitat in site- % of disturb boarder

≥ 50,00 ha and0

30, 00 – 49,99 ha and

1 – 30

5,00 – 29, 99 ha and/or

31 - 60

< 5,00 ha and/or

< 60 %

Overall assessment of FCSOverall assessment of FCS

• method of "the weakest link in the chain" method of "the weakest link in the chain" vs. method "weighted average"vs. method "weighted average"

• our solution: rather complicated weighted our solution: rather complicated weighted average with variable weights for each average with variable weights for each indicator and "state"indicator and "state"

• The weights have not been tested in The weights have not been tested in practice yet.practice yet.

CriterionWeight

of a criterion

IndicatorWeight of an

indicator

State of habitat

A B C D

        Q = 4 Q = 3 Q = 2 Q = 1

Typical habitat species

0.45

Tree species composition

0.4 1.6 1.2 0.8 0.4

Herbs & shrubs

0.05 0.2 0.15 0.1 0.05

Forest habitat structure

0.35

Age structure 0.1 0.4 0.3 0.2 0.1

Regeneration 0.05 0.2 0.15 0.1 0.05

Spatial structure

0.05 0.2 0.15 0.1 0.05

Large-diameter trees

0.05 0.2 0.15 0.1 0.05

deadwood 0.1 0.4 0.3 0.2 0.1

Negative influences

0.1Health 0.05 0.2 0.15 0.1 0.05

BEI 0.05 0.2 0.15 0.1 0.05

+ traditionalismtraditionalism+ pluses and minuses can compensate one pluses and minuses can compensate one

anotheranother- pluses and minuses can compensate one pluses and minuses can compensate one

another another - algorithm is difficult to understand or even to algorithm is difficult to understand or even to

compare with other countriescompare with other countries- usage of „triple weights": two "official" weights usage of „triple weights": two "official" weights

and limits used in each particular indicator => and limits used in each particular indicator => certain unclearnesscertain unclearness

- difficult calculation and reasoning of weightsdifficult calculation and reasoning of weights