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Ann. Ist. Sper. Selv. - Vol. 30, Suppl. 2, 2006: 87-92
* Corresponding author: v.ingegnoli@virgilio.it
1 Università di Milano, Dipartimento di Biologia, Via Celoria 26, 20133 Milano, Italy
Aspects of biological diversity in the CONECOFOR plots. VI.
Studies on biological capacity and landscape biodiversity
Vittorio Ingegnoli1*
Accepted 20 December 2005
Abstract – Even if the “species diversity” still represents the main interest of researchers, each level of biological organisation needs
a proper biodiversity assessment. Therefore, while studying the biological level of landscape, it is not sufficient to refer only to species
diversity. That is why, for instance, the phytosociological approach is not completely adequate for the evaluation of the state of landscape
vegetation. A new method able to estimate the structural ψ and functional τ landscape diversity has been recently proposed: it is based
on the biological territorial capacity of vegetation (BTC) and it is useful especially to measure the organisational aspects of biodiversity.
This method helps in the ecological diagnosis of forested landscapes, too. An application of the preliminary stage of this method to 10
CONECOFOR permanent plots in Mediterranean and Boreal forests and a synthetic anticipation on the diagnostic evaluation of a forest
landscape unit is presented in this paper.
Key words: landscape, forest evaluation, biodiversity, BTC.
Riassunto – Aspetti della biodiversità nelle aree CONECOFOR.VI. Il potenziale di naturalità, tendenze dinamiche e capacità biologica.
Anche se la diversità di specie rappresenta tuttora l’interesse maggiore dei ricercatori, ogni livello dell’organizzazione biologica necessita
di misure sulla propria biodiversità. Di conseguenza nello studio del paesaggio non è sufficiente un riferimento limitato alla diversità di
specie: per questo, ad esempio, l’approccio fitosociologico non è del tutto adeguato nello studio della vegetazione del paesaggio stesso.
Recentemente, è stato proposto un nuovo metodo, basato sulla capacità biologico-territoriale della vegetazione (BTC), per rilevare la
diversità strutturale ψ e funzionale τ del paesaggio e soprattutto la diversità di organizzazione dei sistemi ecologici. Questo metodo aiuta
a formulare la diagnosi ecologica dei paesaggi forestati. Viene quindi presentata in questo scritto una applicazione della parte preliminare
di tale metodo su 10 aree permanenti CONECOFOR in foreste mediterranee e boreali e una sintetica anticipazione della valutazione
diagnostica di una unità di paesaggio forestata.
Parole chiave: paesaggio, valutazione forestale, biodiversità, BTC.
F.D.C. 524.634: 180: 187
Introduction
The basic importance of biodiversity is out of dis-
cussion. Each level of biological organisation, from
genetic biodiversity to the entire ecosphere has to be
characterised by a proper degree of diversity, and not
exclusively the species diversity in an ecosystem, in
a landscape or in an ecoregion (MASSA and INGEGNOLI
1999). In addition, the equation “greater biodiversity
equals healthy ecological status” is not applicable in
every ecological system. In recent years, it has been
acknowledged that it was not sufficient to limit the
concept of biodiversity to the scale of species, because
of the Principle of Emerging Properties (NAVEH 1984;
ODUM 1993) and the theory of non-equilibrium ther-
modynamics (PRIGOGINE 1972, 1996). The Principle of
Emerging Properties states that - in a complex system
- the information about the whole is larger than the
sum of information about its parts (WEISS 1969); the
theory of non-equilibrium thermodynamics states
that when an intense energy flux passes through a
system, some dissipative structures appear, in a state
of instability. The self-organised living systems are
able to capture this kind of energy and to utilise it to
produce new structures. Order through fluctuation,
writes Prigogine.
As pointed out by many authors (WALTER 1973;
NAVEH 1984, 1990; FORMAN 1995; PIGNATTI 1994, 1996;
INGEGNOLI 1997, 2002), these are also the main reasons
confirming that the phytosociological approach, the
auto-ecological one and the species biodiversity are
not completely adequate for the evaluation of the eco-
Ann. Ist. Sper. Selv. - Vol. 30, Suppl.2, 2006: 87-92
88
V. INGEGNOLI
Aspects of biological diversity in the CONECOFOR plots. VI. Studies on biological capacity and landscape biodiversity
logical state of vegetation. Remember that vegetation
is a basilar component of the landscape: it is not only
a question of spatial scale, while of complex adaptive
living system. Moreover, the analysis of forested tes-
serae needs to be referred to the landscape context
to get a complete diagnostic evaluation. It is crucial
to bypass the concept of sustainability, arriving to the
concept of strategic rebalance (INGEGNOLI 2004) of eco-
logical systems. That is, to pass from a local, limited
ecological rebalance to a broader one, available to
influence an entire environmental system considered
as a living entity.
An ecological diagnosis depends on the compari-
son between the conditions of the examined system
and the conditions of a state considered as normal.
Therefore, this evaluation needs the integration of lo-
cal and species parameters with biodiversity measure-
ments at landscape organisation level. A landscape
ecological method of vegetation survey is needed,
as it will be shown further. The final objective of this
research will be the diagnosis of the permanent for-
ested areas in relation with their landscape units; for
the moment the assessment is limited to the plot areas
and in some cases to their forested tesserae. Following
these concepts, 10 permanent CONECOFOR forest
plots have been assessed in 2003-2004 (PETRICCIONE
2002). These plots can be divided into three groups:
(I) Boreal forests: TRE1 (Lavazè), BOL1 (Renon), FRI2
(Tarvisio), LOM1 (Val Masino); (II) Mediterranean
forests: TOS1 (Colognole), TOS2 (Cala Violina), LAZ2
(Monte Circeo), SAR1 (Marganai); (III) Temperate
forest: CAL1 (Piano Limina).
Methods
Biodiversity depends on two aspects: (a) the di-
versity of the components of ecological systems and
(b) the diversity of their relations in the organisation
of these systems. Both aspects change with the scale.
In order to account for diversity of components and
diversity of relationship between components, the
biological territorial capacity has been used in this
paper. The biological territorial capacity, or BTC
(INGEGNOLI 1991,1999, 2002; INGEGNOLI and GIGLIO 1999),
is a synthetic function referred to a vegetational eco-
coenotope and based on: (1) the concept of resistance
stability; (2) the principal types of ecosystems of the
ecosphere; (3) their metabolic data (biomass, gross
primary production, respiration, R/PG, R/B). These
data are processed to measure the degree of the rela-
tive metabolic capacity and the degree of the relative
anti-thermic maintenance of the principal ecosystems.
This function, reported in Mcal m-2 year -1, can repre-
sent the state of an ecological system and it is propor-
tional to the metastability of the vegetated tesserae.
Thus the BTC indexes allow the recognition:
(i) of regional thresholds of landscape replacement
(i.e. metastability thresholds) during time;
(ii) especially of the transformation modalities con-
trolling landscape changes, through vegetation
changes;
(iii) but also of the second aspect of biodiversity (i.e.
the diversity of the relations between components
in the ecological systems), which concerns the
organisation level of an ecological system.
The study of the first aspect of biodiversity (di-
versity of components) in a landscape presents two
evaluations: functional and structural. After having
analysed the BTC values of the components of a
landscape unit, and using appropriate BTC classes, it
is possible to consider a landscape functional diversity.
Taking into account that in complex adaptive self-
organised systems the diversity of their components
must consider both heterogeneity and information,
the proposed landscape diversity index is:
H (3+D) = τ
where:
H is the Shannon diversity;
D the dominance;
τ the synthetic landscape diversity (INGEGNOLI 2002).
The same equation can be applied also to measure
the structural diversity of a landscape, when referred
to the types of tesserae or ecotopes: in this case the
structural diversity is named ψ (GIGLIO and INGEGNOLI
2005).
In the present CONECOFOR research on landscape
biodiversity, the measures mentioned above have been
applied only in one case: the plot TRE1, at Lavazè, be-
cause of the necessity to study a landscape unit (LU),
not simply the permanent plot. The second aspect
of biodiversity (relationships between components)
was evaluated in every plot, through the estimation
of the BTC.
One of the useful form in which vegetational
characters can be related to landscape ecology is
through a survey schedule, a proper one for each
89
Ann. Ist. Sper. Selv. - Vol.30, Suppl.2, 2006: 87-92
V. INGEGNOLI
Aspects of biological diversity in the CONECOFOR plots. VI. Studies on biological capacity and landscape biodiversity
type of vegetation, for the evaluation of a vegetated
tessera. The schedule has been designed to check
the organisation level and to estimate the metastabil-
ity of a tessera considering both general ecological
and landscape ecological characters: T = landscape
element characters (e.g. tessera, corridor); F = plant
biomass above ground; E = ecocoenotope parameters
(i.e. integration of community, ecosystem and micro-
chore); U = relation among the elements and their
landscape parameters, as indicated by INGEGNOLI 2002
and GIGLIO and INGEGNOLI 2005. In considering a set
of vegetated tesserae, this schedule is very useful to
check and compare the ecological state of each group
of parameters (T, F, E, U), to verify a level of quality
(Q) of each tessera and to estimate the biological ter-
ritorial capacity of the vegetation (BTC).
Results
For the moment, only two sets of data concerning
the boreal forests (4 plot areas and 2 tesserae) and
the Mediterranean one (5 plot areas) are availavle.
The assessment is referred:
(1) To the quality (Q) of the 4 main groups of param-
eters. T, F, E and U) are assessed in percentage on
their maximum possibility:
T. TESSERA (Ts) CHARACTERS : T1- Vegetation
high (meters), T2- Trees cover (%), T3- Structural
differentiation, T4- Interior-margin ratio (%), T5-
Type of forest, T6- Permanence (years).
F. VEGETATIONAL BIOMASS (ABOVE GROUND):
F1- Dead plant biomass in Ts, F2- Litter depth of
the Ts, F3 - pB volume (m3/ha).
E. ECOCENOTOPE PARAMETERS: E1- Dominant
species, E2- Species richness, E3- Key species pres-
ence (%),E4- Allochthonous sp. (%), E5- Infesting
plants, E6- Threatened plants, E7- Plant forms (n°),
E8- Vertical stratification, E9- Renew capacity, E10-
Dynamic state.
U. LANDSCAPE UNIT (LU) PARAMETERS:
U1- Boundaries connections, U2- Source (vs. sur-
roundings), U3- Role in the landscape unit, U4- Dis-
turbance incorporation, U5- Geo-physic instability,
U6- Permeant fauna interest, U7- Transformations
reason of the Ts as landscape element, U8- Land-
scape pathology interference, U9- Permanence
(year).
(2) To the BTC of the plot areas (in 2 cases even of their
tesserae) and their ratio versus the BTC threshold
Figure 1 - Evaluation of the main groups of parameters referred to the
plot areas and tesserae of the boreal forests in North Italy
(2004): T = landscape element characters (e.g. tessera, cor-
ridor); F = plant biomass above ground; E = ecocoenotope
parameters (i.e. integration of community, ecosystem and
microchore); U = relation among the elements and their
landscape parameters).
Valutazione dei principali gruppi di parametri riferita alle
aree permanenti e alle tessere di foresta boreale nel Nord
Italia (2004): T= parametri dell’elemento del paesaggio
(e.g. tessera, corridoio); F= fitomassa del soprassuolo; E
= parametri di ecocenotopo (i.e. integrazione di comuni-
tà, ecosistema e struttura spaziale); U = relazioni fra gli
elementi del paesaggio e i loro parametri.
Figure 2 - Evaluation of the biological territorial capacity (BTC) of the
plot areas and tesserae referred to the boreal forests in
North Italy (2004). Note the comparison with the optimal
BTC threshold of maturity for this type of forest. Ap = plot
areas, Ts = tesserae (landscape ecological omogeneous
element, sensu Zonneveld 1995)
Valutazione della capacità biologico-territoriale (BTC) delle
aree permanenti e delle tessere riferita alle foreste boreali
nel Nord Italia (2004). Si noti il confronto con la soglia
ottimale di maturità per questo tipo di foresta. Ap = aree
permanenti, Ts = tessere (elementi paesaggistici omogenei,
sensu Zonneveld 1995).
Ann. Ist. Sper. Selv. - Vol. 30, Suppl.2, 2006: 87-92
90
V. INGEGNOLI
Aspects of biological diversity in the CONECOFOR plots. VI. Studies on biological capacity and landscape biodiversity
of mature forest (i.e. fluctuation, sensu FALINSKI
1998).
These data are plotted in Figures 1 and 2 for the
boreal forests and in Figures 3 and 4 for the Mediterra-
nean forests, then ranked in Table 1. A synthetic aspect
of the study on landscape biodiversity (the structural
ψ and functional τ) at Lavazè will be presented at the
end of this paragraph. Figure 1 shows that the best
quality of the mentioned parameters pertains to the
ecocoenotope (E), the worst to the vegetational bio-
mass (F). Landscape parameters are more variable.
It seems to be mainly an effect of the management
of these forests. Figure 2 shows that no one of these
forested areas reach the BTC threshold of maturity
and, when both the plot area and its tessera have
been assessed, the BTC of the tessera is a bit higher.
These results may be again due to the management,
but also to the spatially too limited plot area (at least
in assessing landscape characters). Figure 3 shows a
remarkably different situation for the Mediterranean
forests, which present lower values and no dominant
parameter, probably due to the transitional stage be-
tween coppice and high forest. Even in Figure 4, the
differences with boreal forest types are evident: they
present about 10% lower BTC, and 22% lower distance
from maturity (always for management reasons).
Further results concern an assessment related to
the diversity of component at the landscape level,
but this is limited only to the plot TRE1. This small
landscape unit, about 175 ha, dominated by Homo-
gino-Piceetum forest was analysed over three time
periods: 2004, 1998, 1930-40. The unit is composed by 4
ecotopes and presents 11 types of landscape elements:
spruce forest, damaged/cut forest patch, routes/paths,
bog area, grass patches in forest, meadows and pas-
tures, shrub patch, pond, built area, road and parking,
ski path. The measures of functional and structural
landscape diversity (τ and ψ) are reported in Table
2, together with the overall landscape metastability,
LM = τ • BTC. As shown in Table 2, the growing of τ
and ψ are not similar: 3.4% vs 14.3%. This means an
altered situation in the landscape unit, confirmed with
the decrease of LM over the concerned time period
(- 4.9%).
Conclusions
This research is today in progress. It represents a
new and original way to assess the landscape ecologi-
Figure 3 - Evaluation of the main groups of parameters referred to
the plot areas of the Mediterranean forests in Central and
South Italy (2004): (T = landscape element characters (e.g.
tessera, corridor); F = plant biomass above ground; E =
ecocoenotope parameters (i.e. integration of community,
ecosystem and microchore); U = relation among the ele-
ments and their landscape parameters.
Valutazione dei principali gruppi di parametri riferita alle
aree permanenti e alle tessere di foresta mediterranea
nell’Italia Centrale e Meridionale (2004): T= parametri
dell’elemento del paesaggio (e.g. tessera, corridoio); F= fi-
tomassa del soprassuolo; E = parametri di ecocenotopo (i.e.
integrazione di comunità, ecosistema e struttura spaziale); U
= relazioni fra gli elementi del paesaggio e i loro parametri.
Figure 4 - Evaluation of the biological territorial capacity (BTC) of the
plot areas and tesserae referred to the Mediterranean for-
ests in central and South Italy (2004). Note the comparison
with the optimal BTC threshold of maturity for this type of
forest. Ap = plot areas.
Valutazione della capacità biologico-territoriale (BTC) delle
aree permanenti e delle tessere riferita alle foreste medi-
terranee nell’Italia Centrale e Meridionale (2004). Si noti il
confronto con la soglia ottimale di maturità per questo tipo
di foresta. Ap = aree permanenti, Ts = tessere (elementi
paesaggistici omogenei, sensu Zonneveld 1995).
91
Ann. Ist. Sper. Selv. - Vol.30, Suppl.2, 2006: 87-92
V. INGEGNOLI
Aspects of biological diversity in the CONECOFOR plots. VI. Studies on biological capacity and landscape biodiversity
1930-40 1998 2004
Landscape functional diversity, τ 4.69 4.78 4.85
Landscape structural diversity, ψ 4.63 4.99 5.29
Landscape metastability, LM 24.27 24.16 23,09
Q.T Q.F Q.E Q.U BTC BTC/BTCS H vFM
Plot areas (Ap) and tesserae (Ts) (%) (%) (%) (%) (Mcal/m2/y) (%)* (m) (m3/ha)
BOREAL FOREST
Ap: TRE1 (Lavazè) 70,7 56 82,4 70,7 7,69 81,3 29,3 696
Ts: TRE1 (Lavazè) 70,7 56 95,6 80,4 8,50 90,0 29,5 739
Ap: BOL1 (Renon) 44 44 82,4 55,6 6,38 67,4 27,1 471
Ap: FRI2 (Tarvisio) 66 38,7 78,8 58,7 7,19 76,0 31,1 841
Ts: FRI2 (Tarvisio) 64,7 56 87,6 62,7 7,72 81,7 30,5 827
Ap: LOM1 (Val Masino) 72 46,7 73,6 61,8 6,60 69,8 22,8 431
MEDITERRANEAN FOREST
Ap: TOS1 (Colognole) 65,2 56,5 61,7 59,4 6,68 63,7 15 203
Ap: TOS2 (Cala Violina) 60,9 30,4 58,3 59,4 6,26 59,7 14,7 260
Ap: LAZ2 (Monte Circeo) 62,3 30,4 63,5 48,3 5,71 54,4 10,9 173
Ap: SAR1 (Marganai) 45,5 47,8 73,9 59,4 6,76 64,4 16,6 304
Ap: SIC1 (Ficuzza) 37 41,5 63,1 57,8 5,64 53,5 13,9 204
TEMPERATE FOREST
Ap: CAL1 (Piano Limina) 72 69,7 63,2 69,7 7,68 75,2 27,1 587
Q.T= quality of the landscape element
Q,F= quality of the plant biomass
Q.E= quality of the ecocoenotope parameters
Q.U= quality
(*)BTCs= threshold of mature forest (i.e. fluctuation, sensu Falinski), deduced from the model of Ingegnoli
H= heigh of canopy
vFM= plant biomass volume (measured with the “spiegel relaskope”),
Table 1 - Summary of the assessments on the plot areas of forest pertaining to the CONECOFOR programme in the years 2003-2004 referred to the
landscape ecological biodiversity.
Sintesi dei rilievi sulle aree permanenti del programma CONECOFOR negli anni 2003 - 2004 riferiti alla biodiversità ecologico-paesistica.
Table 2 - Lavazé forest landscape unit. Measures of functional and
structural landscape diversities (τ and ψ).
Unità di paesaggio forestale di Lavazé. Misure di diversità
funzionale e strutturale del paesaggio (τ e ψ).
Figure - 5 Diagnostic evaluation of the forested landscape unit of
Lavazé Pass (Trentino-Alto Adige). The transformation of
this unit has passed through a significant threshold from
a semi-natural to a managed type of forested landscape
(diagnostic model from Ingegnoli & Giglio 2005). HH is
the human habitat estimated in the landscape unit (LU).
Legend: BTChyp = hypothesis of estimation of the BTC
values varying HH in the same LU structure; BTC normal =
data derived from the HH/BTC model (Ingegnoli 2005); Poly.
(BTC normal) = polynomial curve related to the BTC normal
data; vertical segments are the thresholds among different
landscape types (HH<12%: natural L., 12-24 % semi-nat.L.,
24-48 % managed forest L., 48-72 % agricol. L., HH > 72 %
rural L.). Landscape types with HH > 80% are not plotted in
this figure.
Valutazione diagnostica dell’unità di paesaggio forestale del
Passo di Lavazé (Trentino-Alto Adige). La trasformazione di
questa unità ha passato la soglia significativa fra un paesag-
gio forestale di tipo seminaturale e uno di tipo subantropico
(modello diagnostico secondo Ingegnoli e Giglio, 2005).
HH è l’habitat umano stimato nell’unità di paesaggio (LU).
Legenda: BTChyp = ipotesi di stima dei valori di BTC va-
riando HH nella struttura della stessa LU; BTC normal = dati
derivati dal modello HH/BTC (Ingegnoli 2005); Poly.(BTC
normal) = curva polinomiale riferita ai precedenti valori
(BTC normal); i segmenti verticali (HH semi-nat.L., etc.)
distinguono le soglie di passaggio fra i tipi di paesaggio: HH
< 12% naturale, 12-24% seminaturale, 24-48% forestale
gestito, 48-72% agricolo, HH > 72% rurale).
cal characters of vegetation, particularly important to
evaluate forested landscape units and their dynamic
trends. The results from this research seem to be
helpful in biological conservation and land planning
applications. Anyway, it is necessary to remember, as
expressed in the introduction, that the final objective
Ann. Ist. Sper. Selv. - Vol. 30, Suppl.2, 2006: 87-92
92
V. INGEGNOLI
Aspects of biological diversity in the CONECOFOR plots. VI. Studies on biological capacity and landscape biodiversity
of this research would be the diagnosis of the per-
manent forested areas in their landscape units. Only
studying the landscape unit it is possible to understand
the ecological state of a forest, to improve its manage-
ment and to plan the correct human activities. In this
work the evaluation of landscape biodiversity, in both
its aspects of structural heterogeneity and order dif-
ferentiation, is simply indispensable. A first experience
in the diagnostic study started in 2004, analysing and
evaluating the forested landscape unit around the plot
TRE1 (Lavazè). This study is not yet finished, but it
may be useful to anticipate a diagnostic model (GIGLIO
and INGEGNOLI 2005), in which the exceedance of a sig-
nificant threshold (from a semi-natural to a managed
type of forested landscape) of the examined landscape
unit of Lavazè (Figure 5) is shown. This exceedance
was completed in recent few years, mainly due to the
tourist pressure and ski paths.
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