Detectare Defecte Cu Infrarosu

7/27/2019 Detectare Defecte Cu Infrarosu

http://slidepdf.com/reader/full/detectare-defecte-cu-infrarosu 1/10

Integrated methods for analysis of deterioration of cultural heritage:the Crypt of “Cattedrale di Otranto”

Rosella Cataldo a,*, Antonella De Donno b, Giorgio De Nunzio a, Gianni Leucci a,Luigia Nuzzo a, Stefano Siviero a

a Department of Materials Science, University of Lecce, Via Arnesano, 73100 Lecce, Italyb Department of Biology, University of Lecce, Via Arnesano, 73100 Lecce, Italy

Received 30 December 2003; accepted 31 May 2004

Abstract

It is well known that atmospheric agents, pollution, and various stresses are the main causes of deterioration of artistic heritage. For many

monuments, located in coastal sites, the action of sea aerosols is added to these ones, with a peculiar impact. Further damages, sometimes

irreversible, are suffered by the materials because of the growth of many micro-organisms (bacteria, fungi, etc.), under particular physical–

chemical and biological conditions. In this paper we propose a study of the problem of deterioration, covering different aspects and disci-

plines, with the aim to put in evidence parameters and information that can be carried out following different and complementary surveys. We

outline non-destructive, different biological and physical (microclimatic and Ground Penetrating Radar) techniques to investigate these dam-

ages in the Crypt of the “Cattedrale di Otranto”, situated in the south part of Italy. Geographical Information System (GIS) plays an important

role in the complex task of managing such different type of data. Integrating the data about cultural asset in an urban environment in a GIS

environment, we have the possibility to make more effective decisions regarding the safeguard of the heritage.

© 2005 Elsevier SAS. All rights reserved.

Keywords: Deterioration of cultural heritage; Microclimatic investigation; Georadar survey; GIS

1. Research aims

In the last few decades, the deterioration of stone build-

ings has particularly drawn the attention of scientists due to

the need for protection, especially in polluted environments.

The stone deterioration can be attributed to many different(physical, chemical, and biological) causes. Moreover numer-

ous studies have shown the complexity of relationship

between biological and physical agents of degradation [1].

We performed different, integrated researches, outlining a

method that permits us to individuate, with a coherent inter-

action of cause–effect, the “internal” factors that produce dete-

rioration.

As a subject of investigation we used a truly magnificent

monument, the Crypt of the “Cattedrale di Otranto” (Fig. 1a);

the columns (Fig. 1b) show various forms of decay, included

mildew, efflorescence, and moulds. Some examples of this

deterioration are given in Fig. 2.

In literature reviews focused on fungal growth, this dete-

rioration is attributed to the presence of water and/or mois-

ture in the porous material that occurs in water-damaged andhumid buildings, due to poorly manufactured constructions

and inadequate maintenance [2].

The first step of this study was to isolate the moulds grow-

ing on the columns and to construct distribution maps. Then

we investigated the influence of the environment upon colo-

nisation and growth of these micro-organisms, monitoring the

microclimate inside the Crypt, especially the thermo-

hygrometric conditions.

In this way we also inquired the physical causes that can

directly favour the degradation of the stone. In fact, moisture

transport within a pore system and the changes resulting from

variations in environmental condition, temperature, and rela-

tive humidity, are the key to understand the development of

the observed deterioration patterns. This knowledge permits

* Corresponding author.

E-mail addresses: [email protected] (R. Cataldo),

[email protected] (A. De Donno), [email protected](G. De Nunzio), [email protected] (G. Leucci), [email protected]

(L. Nuzzo), [email protected] (S. Siviero).

Journal of Cultural Heritage 6 (2005) 29–38

http://france.elsevier.com/direct/CULHER/

1296-2074/$ - see front matter © 2005 Elsevier SAS. All rights reserved.

doi:10.1016/j.culher.2004.05.004



Fig. 1. (a) Localisation of the Crypt of “Cattedrale di Otranto”, (b) map of the Crypt.

30 R. Cataldo et al. / Journal of Cultural Heritage 6 (2005) 29–38



the optimisation of the thermal and physical parameters toavoid or at least minimise this process on the materials.

Also buried wet structures could be involved in the pro-cess of deterioration, therefore, we performed in addition aGround Penetrating System survey, with the aim to localisethese discontinuities and to analyse their influence.

Geographical Information System (GIS) [3], in our caseESRI ArcView, provides the tools to manage these collecteddata. Through GIS we access to these heterogeneous data and

applications, establishing links between spatial data and thedatabase of features, enhancing the process of discovery anddynamic interpretation.

The final product is an overall quality map of the condi-

tion of the cultural heritage that permits us to make moreeffective suggestions to obtain suitable conditions for the con-servation of works of art.

2. Introduction

Here, we describe the scenario of the state of conservationof the Crypt, preliminary to discuss themechanism that causesbiological and physical deterioration.

The Crypt of the “Cattedrale di Otranto” was founded in

1080, built in the middle of XII century, and partially rebuiltin 1481. The 42 columns within the interior are different forsize of diameters and various materials are used such as:marble, granite, and breccias. Table 1 shows a classification

of the columns with respect to the materials. The capitals of

the columns and the walls are built with a very porous

Miocene’s limestone said “Pietra Leccese”, but in our case

evident tracks of damages are visible only on the capitals.

Table 1 also shows the state of conservation and the per-

centage of growth of moulds on the columns. For example,

the column labelled C5 presents relevant superficial fractures

that favour the channelling of waters through the substrates,

evidenced by the strong variation in colour of themarble along

the deepest longitudinal fracture. Marble column C6 instead

presents an organic cladding on the surface and deeper frac-

tures than C5, but these fractures were filled with stucco. The

granite columns exhibit no visible superficial fractures; onthe breccia columns many veins are visible, due to the inter-

nal constitution.

We observed that the damages are not uniformly distrib-

uted on the shafts and the capitals. This is because of these

porous materials present very different properties in the

mechanism of deterioration, and it has still not been possible

to model the behaviour of them, resulting from anisotropy of

the mineral grains [4].

In literature the deterioration of porous materials is exten-

sively discussed [5–7]. The decomposition is due to chemi-

cal alterations and/or to temperature fluctuation.

In general water can enter a porous material either as aliquid or vapour; if it moves as a liquid, it will be able to

transport salts; if as a vapour, it may be retained through

hygroscopicity.

Two types of condensation may be distinguished: surface

condensation and microcondensation (or capillary condensa-

tion) in pores, both with different features. The transition point

between these two mechanisms defines the critical moisture

content, Wc, of a porous material; these parameters are con-

stant for each material and depend mainly on porosity and

pore-size distribution. The distribution of moisture within

stone depends also on environmental condition. The maxi-

mum of moisture content resulting from wet–dry cycling is

closer to the surface in denser stones, and deeper and broader

in coarse, porous materials. In those events salts can be origi-

Fig. 2. Deterioration on the capitals and the shafts.




nated from various sources: air pollution, deicing salts, soil,

sea spray, inappropriate treatments, or interaction between

building materials. These salts become evident as efflores-cences on random bricks soon after the construction of the

masonry.

In Section 3 of this paper we describe the evidences and

the results for each type of investigations performed, making

some considerations.

In Section 4 we integrate the whole obtained results pro-

viding some conclusions.

3. Experimental section

3.1. Biological investigation

First of all the columns with greater fungi growth was iden-

tified and sampled through the method of direct observation

(NORMAL 19/85) [8]. The percentage of molds distribution

is shown in Table 1, and a spatial representation of these con-

centrations is drawn in Fig. 8.

Important samples were drawn by the shafts of columns

A1, A3, and C2 (Fig. 1b) and the capitals of columns A3, C2,C5, and A7. The sampling was carried out by scraping the

superficial layer of the mould using a sterile bistoury. The

material was collected in sterile Petri dishes and analysed

1 day after collection. Two samplings were carried out, dur-

ing spring (15th May 2003) and summer (3rd July 2003),

when the Crypt was closed to visitors.

The isolation of the moulds was carried out according to

the instructions and methods reported on the NORMAL 9/88

[9] and NORMAL 25/87 [10].

Mycological agar and malt extract-agar medium were

used for fungi isolation. All coltures were incubated at 28 °C

for 5–7 days. Identification of fungi was mainly carried outon the basis of the macroscopic features of colonies and on

the micromorphology of reproductive structures, according

to many authors [11–13].

Microbiological analyses revealed the presence of fungi

belonging to the following species:

• Acremonium strictum and Trichoderma viride on the shaft

of columns A1 e A3, sterile mycelium (fruit bodies absent)

on the capitals of column C2;

• Trichoderma viride, Botrytis cinerea, Phoma medicagi-

nis, and Acremonium strictum on the shaft of columns C2,

C5 e A7. On the shaft of column A3 mycelium remains

sterile.

The moulds found on the columns are usually ubiquitoussaprophytes whose conidia are plentifully distributed in the

atmosphere. The Trichoderma and Phoma species, the main

causes of deterioration of monuments have been often iso-

lated in many German sandstone monuments [14,15] and from

weathered sandstone in the Cathedral of Salamanca, Spain,

in association with algae [16].

The genus Acremonium is a large and diverse group of

hyphomycetes that are widespread in soil and plant debris.

Acremonium strictum is especially abundant in wet environ-

ments and typically has very high water requirements. This

species has been often isolated indoor and in very few papers

it is considered as a cause of biodeterioration of monuments. Alternaria is a common mold, it is prevalent in outdoor

environments, and may colonise indoor substrata where con-

ditions are suitable. In particular Alternaria alternata is the

most common indoor species. It is capable of degrading cel-

lulose and is frequently found on drywall paper, ceiling tiles,

and wood. A. alternata was found on Carrara marble blocks

located in the terrace of Messina Museum [17].

Among the strains isolated in Crypt of Otranto there are

dematiaceous such as Phoma and Alternaria. This “black

fungi”, are the most conspicuous and probably the most dam-

aging organisms attacking and even penetrating the surfaces

of stone monuments [18]. These black fungal activities are

enhanced by climatic conditions (high irradiation, alternat-

ing cycles of extreme wetting and drying).

Table 1

State of conservation of the columns in the Crypt and percentage of growth

of moulds on them

Column Diameter

(m)

Moulds on the

columns (%)

Materials and damages

A1 0.29 27 Breccia

A2 0.24 6 Marble-fracture

A3 0.32 43 Marble-multiple fractures




A7 0.23 49 Breccia

A8 0.25 4 Marble-micro fractures

B1 0.24 14 Marble-fracture (80 and 120 cm)

B2 0.27 8 Marble-diagonal fracture (50 cm)

B3 0.32 25 Marble-fracture on the bottom

B4 0.32 6 Marble-micro fractures

B5 0.3 8 Marble-micro fractures

B6 0.33 10 Marble-micro fracturesB7 0.32 0 Granite-fracture on the top

B8 0.37 9 Granite-fracture

C1 0.26 16 Marble-fracture (30 cm)

C2 0.32 37 Marble-multiple fractures

C3 0.28 15 Marble-micro fractures






D1 0.27 24 Breccia

D2 0.24 13 Marble-longitudinal fractures

D3 0.33 17 Marble without damage

D4 0.31 5 Marble without damageD5 0.32 8 Marble-micro fractures

D6 0.32 13 Marble-multiple deep fractures

D7 0.29 1 Marble-multiple fractures

D8 0.35 0 Breccia

J6 0.32 0 Granite-fractured

F6 0.3 0 Marble-micro fractures

E6 0.31 2 Marble-longitudinal fracture

G6 0.27 0 Granite

E7 0.29 7 Marble-longitudinal fracture

F7 0.29 24 Marble-longitudinal fracture




The presence of these organisms on the columns of the

Crypt of Otranto shows a situation of deterioration because

of the hyphal growth in substratum.

In literature it is outlined that undoubtedly the most impor-

tant factor for determining if mould growth will start in abuilding is the knowledge of water activity (aw) [19]. Most of

the moulds have their optimal aw at 0.96–0.98, however the

lowest values for filamentous fungi is 0.8 [11]. In these papers

there are many examples that show that moulds can grow

either if the indoor air temperature is 22 °C and the RH is

50% or if a cold wall has a temperature of 15 °C and the RH

is about 80%.

In the next subsection we will show that these conditions

are actually fulfilled in many periods of the year in the Crypt.

At the present time, we do not have a non-destructive appa-

ratus to estimate the aw parameter on the columns. However,

we think we will go on with our biological–physical investi-gation to evaluate the distribution of water in the columns, in

order to better verify the role played by different organisms

in the colonisation of a building stone.

In conclusion, the growth of moulds may be reduced and/or

prevented by checking microclimatic factors, as we will bet-

ter discuss in microclimatic section. Besides we suggest a

recurring mechanical cleaning of the columns in order to avoid

the accumulation of organic sediments that acts as medium

for fungi. On the contrary, we do not advise the direct meth-

ods (use of biocides) of removal of moulds since they could

corrode the columns stone and would not assure anyway a

lasting effect.

3.2. Microclimatic investigation

The thermo-hygrometric conditions of the Crypt have been

monitored during a period from February 2003 to January

2004. To determine the climatic causes that can favour bio-

logical and physical deterioration we took into account the

synergistic effects of the building structure, of the external

climate and of the technological systems, in this case of an

air drier.

Before discussing the method and the experimental evi-

dences we give some further information about the Crypt.

The Crypt confines with the outside (Fig. 1a,b) on the NWside (where door P3 is) and on the NE side (the apses, with

the small windows W1–W4). Door P3 is generally closed,

and is opened only in special circumstances to let people enter

the Crypt without passing through the “Cattedrale”, and dur-

ing the cleaning times. The Crypt communicates with the

“Cattedrale” through doors P1 and P2: P1 is normally open

and is used to access the Crypt (through the staircase S1),

while P2 is always closed. Windows W1 and W2 in the apse

are sometimes opened, causing a strong air flow with the

entrance door P1. When these windows and door P3 are

closed, the air flow is not appreciable. Window W5 is walled

up, behind of it there is a building.

The methodology used to study the dynamics of the inter-

nal microclimate is well known [5,6,20,21].

The measurements of the main indoor and outdoor cli-matic parameters, i.e., air (T ) and surface (T sur) temperature,

relative humidity (RH), specific humidity (SH), dew-point(DP), dew-point spread (DDP), and air velocity were per-

formed at different times in strategic points of the Crypt. Inparticular T , RH, and air velocity were continuously recorded

near particularly damaged, or rich in moulds, walls and col-umns. T and RH distributions were also recorded in horizon-tal cross-sections of the Crypt, on a 59 points grid, at about1.30 m from the ground, every 3 h since the opening of the

Crypt (8 am) until its evening closing time. Temperature wascontinuously measured in three points along a vertical line,in order to study vertical air stability and dust/pollutant trans-port.

The most important results are summarized in Figs. 3–5.The Crypt is weakly affected by the external environment,

from which it is separated by thick walls. By comparing the

outside and inside air temperature measurements we can arguethat the external influence is substantially filtered out by thebuilding mass. Fig. 3 shows the air and stone surface tem-peratures inside the Crypt and the air temperature outside it,in a period when the weather was rapidly changing; while

outside temperature excursions are really large with sharpchanges, inside values show a slow trend towards larger T

values, with only some rare peaks.

When windows W1 and W2, and door P3, are closed, theT distribution is quite homogeneous.

Fig. 4 shows the T perturbation due to the opening of thewindows and to the consequent air flow between them and

the entrance door P1. After closing the windows, 1 h is suf-

ficient to reset the environment to its former conditions, with

an almost uniform distribution of T .

Vertical stability measurements show that air temperature

is generally higher near the ceiling than at about 1 m from the

ground, the average difference is about 0.5 °C. The conse-

quence is thermal layering and stability. This situation helps

to protect the Crypt from diffusion of dust and pollutants,

which remain confined near the ground.

The Crypt is equipped with an air drier (labelled AD in

Fig. 1b), while no heating system exists, and the heating con-

Fig. 3. Temperature measurements inside and outside the Crypt show the

filtering effect of the building.




tribution of artificial lighting is almost negligible. The dan-

gerous effects of HVAC (heating, ventilation, and air condi-

tioning) devices on works of art have been studied extensively

[21].

The air drier in the Crypt operates irregularly and it is

manually turned on for few hours during a day; thus its dis-continuous action has poor influence in limiting the growth

of moulds.

The air drier influence is noticeable in the spring survey

(Fig. 5) and in autumn/winter when the device is working. In

this case the RH distribution shows an appreciable difference

between RH values measured near the device and far from it,

in Fig. 5 the maximum difference is about 10% RH. When

the device is off, there are generally no fluctuations larger

than 2% or 3% RH.

In summer the air drier has no significant effect, probablybecause RH attains too high values (60–80%, and more).

In all seasons, walls and columns surface temperatures are

found to be larger (by at least 2 °C) than the air dew-point.

This excludes surface condensation. As RH gradients near

Fig. 4. Spatial distribution of the temperature (°C) at h 8:00 am on 26/06/2003, after opening the two apse windows. Temperature in the Crypt is lower than

outside, so the air near the window has higher T values than the air far from the apse.

Fig. 5. Spatial distribution of relative humidity (%) in spring at h 12: 00 on 08/04/2003.




the stone show that cyclic condensation/evaporation phenom-

ena occur in various moments of the day, we may conclude

that they take place for Kelvin effect in poreswith radius lower

than 10–2 µm, because of the high RH level near the stone.

Furthermore the high values of RH in the Crypt through

the whole year suggest us that an important rising of water

from the pavement may be. To assess the presence of this

phenomenon we performed a ground penetrating radar (GPR)

survey, discussed in the next subsection.

Microclimate conditions may also be responsible for stone

aggression by air pollutants. The atmospheric pollution is one

of the “external” factors that cause the accelerated deteriora-

tion of the exposed stonework, but Otranto is a relatively small

town facing the sea, it is well ventilated and with severe traf-

ficlimitation, so atmospheric pollution is low. Furthermore,

the region itself is not highly industrialised so the levels of

pollutant emission from anthropic activities are low. Our sur-

veys put in evidence that in autumn and in winter the stone

surfaces generally have slightly higher temperature T sur than

the air nearby. Therefore, in this period the thermophoretic

flow reduces the velocity of other deposition processes, pro-

tecting the stone. On the contrary, in the spring/summer period

the air is often warmer than the stone and thermophoretic

deposition probably occurs.

Finally, we observed that, as we already pointed out, the

condensation/evaporation cycles in the micropores, also

favoured by the air drier switching, takes place in all seasons.

The maximum measured absolute value of the SH gradient is10–2 g/kg/mm, during both condensation and evaporation. We

recall that net resultant of the Stefan flow and diffusiophore-

sis favour or contrast the other deposition processes, accord-

ing to the sign of the SH gradients.

3.3. Ground penetrating radar investigation

It is well known [22,23] that GPR technique uses high fre-

quency electromagnetic waves to investigate the shallow sub-

surface, taking into account the contrast of dielectric proper-ties. The presence of water plays a major role for two reasons:

on one hand its high dielectric constant causes the medium

velocity to decrease, on the other hand high moisture content

causes electromagnetic energy attenuation, determining an

increase in the electric conductivity. Consequently, the pen-

etration depth can be highly reduced and few or no reflec-

tions are observed in GPR radar sections above wet zones.

A GSSI Sir System 2 with a 500 MHz (central frequency)

antenna was used for the GPR survey. The data were acquired

with 512 sample per scan, eight bit data word length, record-

ingtime window of 80 ns and a manual gain function.A recon-

naissance survey was carried out in continuous mode, in the

Crypt along 0.4 m spaced parallel profiles (Fig. 6a). The sur-

veyed area was 12 m by 22 m.

To convert the time scale in depth, the subsurface electro-

magnetic wave velocity was estimated by two Wide Angle

Reflection and Refraction (WARR) measurements (whose ini-

tial midpoint position is shown with a dot in Fig. 6a), as well

as by one Common Depth Point (CDP) gather. Within the

experimental errors, from the results obtained by the WARR

and CDP measures, the velocity value for the ground direct

wave was estimated of 0.09 m/ns. This value has been used

for depth conversion.In Fig. 6b is shown the radar section relating to the

WARR1 profile. Some deeper reflections (between 20 and

60 ns) can be observed which are due to objects located above

the pavement of the Crypt.

Fig. 6. (a) Radar profiles location in the Crypt of Cathedral, (b) radar section relating to the WARR 1 profile.




To obtain further information on the presence of wet cavi-

ties, appropriate processing has been performed for easier

interpretation. Processing steps can be summarised as fol-

lows:

• horizontal scaling (50 scan/m). It allows an interpolation

of the data in the X-direction using markers set manually

or automatically extracted from the data;

• background removal. The filter is a simple arithmetic pro-

cess that sums all the amplitudes of reflections recorded at

the same time along a profile and divides them by the num-

ber of traces summed. The resulting composite digital

wave, which is an average of all background noise, is then

subtracted from the data set;

• Kirchhoff migration [24]. Using a constant average veloc-

ity value (0.09 m/ns) is possible to trace back the reflec-

tion and diffraction energies to their “source”.

Fig. 7 exhibits the radar section of the profile labelled A1 in

Fig. 6b, before (a) and after (b) the above-described pro-cesses. A close examination of the data shows the presence

of numerous reflection hyperbolae from point sources.

A very strong anomaly (labelledA) is easily identifiable at

time ranging from about 6 to 30 ns (0.27–1.35 m in depth)

and at a distanceof about 3–4 m on the X -axes. Similar anoma-

lies are observed at almost the same abscissas on the adjacent

profiles. These anomalies are probably related, for shape and

dimension, to anthropic structures.

The hyperbolic diffractions in zone C (Fig. 7b) are traced

back after the Kirchhoff migration to point-like zones. They

are likely due to small objects such as pebbles.

No other relevant anomalies were observed, probably due

to either more conductive soil (elevate moisture content) or

more homogeneous subsoil.

Furthermore by adopting the horizontal time slice tech-

nique [23,25] within specific time intervals we obtained a

more precise localisation of theanomalies. They can be attrib-

uted to buried archaeological features, voids or important

stratigraphic changes [25].

Using this data representation the areas of low reflection

amplitude (or energy) can be attributed to uniform matrix

materials or quite homogeneous soils; moreover one can

obtain information on spatial localisation of the most impor-

tant anomaly A (Fig. 8).

This research point out the presence of a relatively high

degree of moisture in the subsoil of the Crypt. This relatively

high degree of moisture plays an important role in the degrade

processes that can be observed on the columns and on the

frescos inside the Crypt. The moulds distribution superim-

posed to the GPR time slice (Fig. 8), confirm that high moulds

distributions are observed in zones with low radar energy.

The shape and the size of the high amplitude anomaly sug-gest that it is related to the probable presence of a void (likely

a tomb).

4. Conclusions

Three complementary researches have been performed to

investigate the deterioration in the Crypt of “Cattedrale di

Otranto”.

From the microclimatic survey, the conditions in the Crypt

look quite stable, due to the absence of any heating system,

to a moderate heating by sun radiation and to a negligible

contribution of artificial lighting. The main source of varia-

tion for thermo-hygrometric parameters is the opening of the

Fig. 7. Radar section relating to the A1 profile acquired with 500 MHz centre frequency antenna before (a) and after (b) the processing steps as described in

Section 3.3.




windows and the door toward the outside, which causes astrong flow of air, with different temperature and moisture

content.

The field surveys have shown that the Crypt has a micro-

climate characterized by large RH values in all seasons. This

fact, coupled with high air temperatures, in particular in the

summer, and the poor air flow through the environment cause

the moulds proliferation.

The possible interventions that could limit the growth of

moulds are:

• to increase ventilation, by opening more frequently win-

dows W1/W2 and door P2, at present permanently closed.

Until 1980 this door was normally open, and according tosome witnesses at that time no dramatic proliferation of

moulds existed;

• to turn on the air drier through the whole day, at small

regime but with regularity, to avoid phenomena of very

dangerous cycles of absorption/evaporation on the stone.

Deterioration is also due to the presence of buried cavities

containing water (or wet materials) that can give an impor-

tant rising of water from underground.

GIS gave us the possibility to analyse this large amount of

spatial data, different, as source and format (CAD maps,

physical and chemical measurements) were the great advan-

tages:

• it is a powerful tool that favour the total integration of the

whole information, driving the conclusions;

• it allows to co-ordinate easily a large group of researchersthat co-operate in the same project, especially when geo-

graphically distributed;

• it allows public administrators, who already use GIS for

various tasks in other fields, to maintain maps of historical

buildings over many years.With such an interface the plan-

ning and the analysis of safeguard of historical buildings

can be improved.

This research shows that through productive interchange of

knowledge and experiences, it is possible to address major

problems and issue related considerations, which are of rel-

evancy to investigate the causes of deterioration of cultural

and historical materials.We think also that the interest of this work overcomes the

local dimension, as far as the problems of deterioration are

similar to other Italian and European monuments of very rel-

evant artistic importance.

Acknowledgements

The authors are very grateful to Dr Annarita Turnone and

Dr Stefano Margiotta for their precious collaboration during

data acquisition. Thanks are due to Dr Adriana Bernardi for

her constructive advice and suggestions.

Fig. 8. Time slices of GPR anomalies superimposed to the layer of the moulds distribution (%).




References

[1] C. Urzi, W.E. Krumbein, Microbiological impacts on the cultural

heritage, in: W.E. Krumbein, P. Brimblecombe, D.E. Cosgrove,

S. Staniforth (Eds.), Durabilityand Change: the Science, Responsibil-

ity, and Cost of Sustaining Cultural Heritage, Wiley J. & Sons, 1994,pp. 107–135.

[2] J.D. Miller, P.D. Haisley, J.H. Reinhardt, Air sampling result in rela-

tion to extend of fungal colonization of building materials in some

water-damaged buildings, Indoor Air 10 (2000) 146–151.

[3] P.A. Burrough, R.A. Mc Donnell, Principles of Geographical Infor-

mation Systems, Blackwell Publishers Ltd, 1999.

[4] J.D. Sage, Thermal Microfracturing of Marble, Engineering Geology

of Ancient Works, Monuments and Historical Sites, in: P.G. Marinos,

G.C. Koukis (Eds.), Bakelma, Rotterdam, 1988, pp. 1013–1018.

[5] D. Camuffo, Microclimate for Cultural Heritage, Elsevier, Amster-

dam, 1998.

[6] D. Camuffo, Indoor dynamic climatology: investigations on the inter-

actions between walls and indoor environment, Atmos. Environ. 17

(1983) 1803–1809.

[7] N.S. Baer, R. Snethlage, Saving our architectural heritage, The Con-servation of Historic StonesStructures, John Wiley & Sons Ltd, 1996.

[8] Normal Recommendations 19/85 Beni culturali—Materiali lapidei

naturali ed artificiali—Allestimento di preparati biologici per

l’osservazione al microscopio ottico, Consiglio Nazionale Ricerche,

Istituto Centrale Restauro, Rome, 1985.

[9] Normal Recommendations 9/88 Microflora Autotrofa ed Eterotrofa:

Tecniche di Isolamento in Coltura, Consiglio Nazionale Ricerche,

Istituto Centrale Restauro, Rome, 1988.

[10] Normal Recommendations 25/87 Microflora Autotrofa ed Eterotrofa:

Tecniche di isolamento e di mantenimento in Coltura Pura, Consiglio

Nazionale Ricerche, Istituto Centrale Restauro, Rome, 1987.

[11] O. Fassatiova, Moulds and filamentous fungi in technical microbiol-

ogy, in: M.E. Bushell (Ed.), Progress in Industrial Microbiology, vol.

22, Elsevier, Amsterdam, 1986.

[12] G.S. Hoog de, Taxonomic aims in the yeast-like fungi, in:G.S. Hoog de,M.T. Smith, C.M.A.Weijman (Eds.), Proceedings of an

International Symposium on the Perspectives of Taxonomy, Ecology

and Phylogeny of Yeasts and Yeast-like Fungi, Elsevier, Amsterdam,

1987, pp. 13–16.

[13] M.B. Ellis, More Dematiaceous Hyphomycetes, CAB International

Mycological Institute, Kew, 1976.

[14] C. Saiz-Jimenez, Deposition of anthropogenic compounds on monu-

ments and their effect on airborne microorganisms, Aerobiologia 11

(1995) 161–175.

[15] K. Petersen, J. Kuroczkin,A.B. Strzelezyk, W.E. Krumbein, Distribu-tion and effects of fungi on and in sandstones, in: D.R. Houghton,

R.N. Smith, H.O.W. Eggins (Eds.), Biodeteration 7, Elsevier Applied

Science, London, 1988, pp. 455–460.

[16] M.A. De la Torre, G. Gomez-Alarcon, P. Melgarejo, C. Saiz-Jimenez,

Fungi in weathered sandstone from Salamanca cathedral, Spain, Sci.

Total Environ. 107 (1991) 159–168.

[17] C. Urzi, F. De Leo, P. Salamone, G. Criseo, Airborne fungal spores

colonising marbles exposed in the terrace of Messina Museum, Sicily,

Aerobiologia 17 (2001) 11–17.

[18] E. Diakumaku, A.A. Gorbushina, W.E. Krumbein, L. Panina,

S. Soukharjevski, Black fungi in marble and limestones—an aestheti-

cal, chemical and physical problem for the conservation of monu-

ments, Sci. Total Environ. 167 (1–3) (1995) 295–304.

[19] P. Gervais,W. Grajek, M. Bensoussan,P.Molin, Influence of thewater

activity of a solid substrate on the growth rate and sporogenesis of

filamentous fungi, Biotechnol. Bioeng. 31 (1988) 457–463.

[20] D. Camuffo, A. Bernardi, The microclimate in the Sistine Chapel,

special issue, Joint Edition: European Cultural Heritage Newsletters

Res. and Bollettino Geofisico 18 (2) (1995) 7–33.

[21] D. Camuffo,A. Bernardi, G. Sturaro, A. Valentino, The microclimate

inside the Pollaiolo and Botticelli rooms in the Uffizi Gallery, Flo-

rence, J. Cult. Herit. 3 (2002) 155–161.

[22] J.M. Reynolds, An Introduction to Applied and Environmental Geo-

physics, John Wiley & Sons Ltd. Baffins Lane, Chichester, West

Sussex PO19 1UD, England, 1998.

[23] L.B. Conyers, D. Goodman, Ground-penetrating Radar—An Intro-

duction for Archaeologists, Alta Mira Press, Walnut Creek, 1997.

[24] O. Yilmaz, in: B. Edwin, Neitzel (Eds.), Seismic data processing.

Society of Exploration Geophysicists, 1987 Series Editor, Tulsa,USA.

[25] M.T. Carrozzo, G. Leucci, S. Negri, L. Nuzzo, GPR survey to under-

stand the stratigraphy at the Roman ships archaeological site (Pisa,

Italy), in: Archaeological Prospection 10 (1), 2003, pp. 57–72.


Documents

Detectare Defecte Cu Infrarosu