Oscillations of temperatures in Piedmont caves remarkable for speleofauna.

Oscillations of temperatures in Piedmont caves

remarkable for speleofauna

Luigi Motta, Michele Motta

Department of Earth Sciences

University of Turin

Turin, Italy

[email protected]

[email protected]

in some interesting caves from a biological point of view. The data analysis showed that thermic conditions are constant for each cave, but vary from one cave to another. This has allowed to subdivide the Piedmontese cave environments into four groups. The first includes the larger caves. The temperature is stable at daily scale (<0.05 °C) as at annual scale (>0.6 °C). The second includes medium-size cave environments, well insulated from the external environment: the annual and daily thermic excursions are very limited. The third includes both small caves and the entrance of big caves. The daily temperature range is from 0.2 to 1° C, the annual thermic excursions exceed 5° C. The fourth group includes small high-altitude caves, in which there is ice in January. Because of this, the daily temperature range is smaller than those of the third group (0.05-0.35° C).

Caves; temperature variations; thermic excursions; Italy

I.

T

CAVELAB

The interdisciplinary project CAVELAB "From microclimate

to climate change: Caves as laboratories for the study of the

effects of temperature on ecosystems and biodiversity ' was

born in 2013 at the University of Turin, with a team composed

of members of the departments of Animal and Human

Biology, Earth Sciences, General Physics, Plant Biology and

Analytical Chemistry [3].

The central theme of the project is the study of the influence

of temperature on the dynamics of the ecosystems of the

caves. The fauna of the Piedmontese caves is quite

well-known. Therefore, we selected 22 Piedmont caves, among

those that are of particular interest from a biological point of

view. These caves often contain endemic or cryophiles species

that probably are spread during the glaciations, which have

isolated several caves and lowered the temperatures.

The project begins with the characterization of the

environment biotic and abiotic of the caves. The next step takes

into account the influence direct and indirect of factors such as

availability of trophic resources, the human disturbance, the

structure of the biocoenosis and habitats, the former climate

and extension of Quaternary glaciers. The influence of

temperature is evaluated on each part of the ecosystem, by

means of direct measurements and statistical models. The

ultimate goal of the project is: from a scientific point of view,

improve knowledge of the impact on ecosystems of sudden (in

time of the evolution of species) variations of climate such as

the deglaciation, or in a future scenario, the global warming;

from a practical point of view, give advice for the good

management of the tourism inside caves containing sensitive

species.

II.

D

To know the effect of temperature on ecosystems, it is obvious

that we need first to know the temperature of the cave and its

variations, both temporal as spatial. In this paper, in particular,

we will present the data collected by sensors of temperature

(smart buttons) directly in contact with the ground, relatively

far from the walls in caves (listed in tab. I). Several sensors

have worked in troglophile fauna-rich places that are at the

entrance of the cave, but always in the shade. Other sensors

have worked inside the caves, in reputable places, on the basis

of the literature and studies on current wildlife, as fauna-rich

sites (troglobites). The sensors have a nominal accuracy of

more 0.1 ° C and have been adjusted to measure temperature

every three hours. The analyses were performed for the spring

2012 up to half of the summer 2013.

III.

D

We have aggregated the validated data at the monthly level.

It is easy to recognize the typical thermic stability of the cave

environments such as those examined, with low excursions.

Yet each cave has a high variability of thermic conditions: even

by analyzing only the environments far from the entrance to the

cave, we note caves such as Ghieisa with daily excursions of 2

°C approximately and annual excursion of 10 °C

approximately, while other caves, including the biggest, have

very lower excursions: less than 0.5 ° C, also at the annual

level (fig. 1).

Thermic conditions of January are probably, in mountain

environments, the main factor limiting the spread of

speleofaunal species. We have tabulated the data of 2013,

available for all studied caves (tab. 2).

To estimate the annual data, despite the short observation

period, we use only the monthly average temperatures of

January 2013 and July 2012 with their standard deviation (both

calculated on the basis of daily data), and the average of the

This study is part of the CaveLab project “From microclimate to climate change: caves as laboratories for the study of the effects of temperature on ecosystems and biodiversity”, funded by the University of Turin and Compagnia di San Paolo (Progetti di Ateneo 2011 - ORTO11T92F)

thermic daily excursions recorded during two months already

mentioned (tab. III). In the table you can found as well:

- the average of the monthly values already mentioned;

given the relative stability of the hypogeous thermic

conditions, it can be an estimate of the average annual

temperature;

- the difference between the two values; if it does not

indicate the annual thermic excursion (indeed, January and July

are almost never the coldest and the warmest month, see fig. 1),

it gives an idea of the difference between the seasons anyway.

TABLE I. THESTUDIEDCAVES. THECAVESTHATARENOTINLIMESTONES, MARBLES, ORCALCSCHISTSDONOTHAVEKARSTICORIGIN. FORSPIDERSSEE [2], FOR THEOTHER [4] TABLE II. Cave TABLE III. Coordinates TABLE IV. Rock TABLE V. L TABLE VI.

Important troglofaunal species

TABLE VII. Arenarie, Grotta delle

TABLE VIII. 446644E 5062402N 780 m TABLE IX. Limestone, dolomite, sandstone TABLE X. 30 TABLE XI.

Meta merianae, Troglohyphantes, Linyphiidae, Iglica pezzoli TABLE XII. Argentera, Grotta 1 TABLE XIII. 335864E 4918268N 1795 m TABLE XIV. Rockfall blocks TABLE XV. 12 TABLE XVI.

Meta menardi, Lepthyphantes notabilis, Tegenaria silvestris, Amaurobius

TABLE XVII. Bandito, Grotta W del

TABLE XVIII. 374716E 4905527N 714 m TABLE XIX. Pelagic limestone TABLE XX. 69 TABLE XXI.

Nesticus eremita, Meta menardi, Speleomantes strinatii TABLE XXII. Bergovei, Grotta di TABLE XXIII. 442855E 5056806N 415 m TABLE XXIV. Dolomite TABLE XXV. 17 TABLE XXVI.

Nesticus eremita, N. cellulanus, Meta merianus, Lepthyphantes alacris, L. flavipes, Tegenaria silvestris, Diplocephalus latifrons

TABLE XXVII.

Bossea, Grotta di TABLE XXVIII. 407374E 4899582N 836 m TABLE XXIX. Dolomitic limestone with weak metamorp hism TABLE XXX.

28 TABLE XXXI. Nesticus eremita, Troglohyphantes pedemontanus, Tegenaria silvestris, Proasellus franciscoloi, Buddelundiella zimmeri, Trichoniscus voltai, Pseudoblothrus ellingseni, Plectogona sanfilippoi bosseae, Polydesmus troglobius

TABLE XXXII. Caudano, Grotte del

TABLE XXXIII. 403537E 4905362N 780 m TABLE XXXIV. Dolomitic limestone TABLE XXXV. > TABLE XXXVI.

Leptoneta crypticola, Nesticus, Troglohyphantes pluto, Plectogona sanfilippoi sanfilippoi, Duvalius carantii, Bythinella schmidti

TABLE XXXVII. Custreta, Grotta la TABLE XXXVIII. 386340E 5033760N 1386 m TABLE XXXIX. Marble TABLE XL. 18 TABLE XLI.

Troglohyphantes nigraerosae, Nesticus, Meta, Alpioniscus feneriensis, Ischyropsalis, Canavesiella lanai

TABLE XLII. Diau, Tuna del

TABLE XLIII. 350610E 4978860N 1150 m TABLE XLIV. Schist TABLE XLV. 20 TABLE XLVI.

Pimoa rupicola, Linyphiidae TABLE XLVII.

Diavolo, Tana del

TABLE XLVIII. 352140E 4987790N 1414 m TABLE XLIX. Gneiss TABLE L. 14 TABLE LI.

Dysdera, Meta menardi, Pimoa rupicola, Troglohyphantes rupicapra, Linyphiidae, Dellabeffaella olmii

TABLE LII. Dronera, Tana della

TABLE LIII. 408066E 4910960N 525 m TABLE LIV. Calcareous sandstone TABLE LV. 13 TABLE LVI.

Nesticus eremita, Meta merianae, Porrhomma convexum, Troglohyphantes, Linyphiidae, Tegenaria silvestris, Antistea elegans, Diplocephalus latifrons, Plectogona sanfilippoi dronerae

TABLE LVII. Ghiaccio (Buca del

Ghiaccio della Cavallaria) TABLE LVIII. 405988E 5041429N 1548 m TABLE LIX. Eclogitic micaschist TABLE LX.

24 TABLE LXI. Meta merianae, Troglohyphantes TABLE LXII.

lucifuga, Tegenaria TABLE LXIII.

Ghieisa d’la Tana TABLE LXIV. 359634E 4967937N 835 m

TABLE LXV.

Serpentinite TABLE LXVI. 30 TABLE LXVII. Meta menardi, Linyphiidae, Amaurobius, Liocranum rupicola, Dellabeffaella olmii

TABLE LXVIII. Glace, Borna d’la

TABLE LXIX. 348747E 5066007N 1605m TABLE LXX. Gneiss TABLE LXXI. 20 TABLE LXXII. Troglohyphantes TABLE LXXIII. lucifuga, Meta merianae TABLE LXXIV. TABLE LXXV. TABLE LXXVI. TABLE LXXVII. TABLE LXXVIII.

Ivery, Grotta A 407363E 5049504N 669 m

Limestone ~5 Troglohyphantes, Meta merianae TABLE LXXIX.

Maestro, Buco del

TABLE LXXX. 360380E 4949700N 750 m TABLE LXXXI. Marble TABLE LXXXII. 17 TABLE LXXXIII.

Meta menardi, Pimoa rupicola, Tegenaria silvestris TABLE LXXXIV. Napoleone, Grotta Testa di TABLE LXXXV. 363263E 4997329N 450 m TABLE LXXXVI. Blocks of metagranit e TABLE LXXXVII. 13 TABLE LXXXVIII. Meta bourneti, M. menardi TABLE LXXXIX. Om Salvej, Caverna del TABLE XC. 417306E 5050186N 1025 m TABLE XCI. Eclogitic micaschist (likely quarry) TABLE XCII. 16 TABLE XCIII.

Meta merianae, Lepthyphantes leprosus, Troglohyphantes lucifuga, Linyphiidae, Araneus marmoreus, Tegenaria silvestris

TABLE XCIV. Partigiano, Buco del

TABLE XCV. 364416E 4929787N 1170 m TABLE XCVI. Gneiss TABLE XCVII. 12 TABLE XCVIII. Troglohyphantes? TABLE XCIX. Pugnetto, Borna Maggiore del TABLE C. 375551E 5014621N 742 m TABLE CI. Calcschist TABLE CII. 76 TABLE CIII.

Nesticus eremita, Meta menardi, M. merianae, Labulla thoracica, Leptyphantes pallidus, Troglohyphantes, Tegenaria silvestris, Amauronius, Dellabeffaella roccai, Alpioniscus feneriensis

TABLE CIV. Servais, Borna del

TABLE CV. 369011E 5020340N 1420 m TABLE CVI. Clorite-schist (Quarry) TABLE CVII. 12 TABLE CVIII. Troglohyphantes? TABLE CIX. Vernante, fort A TABLE CX. 382565E 4901169N 800 m TABLE CXI. Brickwork (An undergrou nd fortress) TABLE CXII. 50 TABLE CXIII.

Leptoneta, Nesticus eremita, N. morisii, Meta merianae, M. menardi, Pimoa rupicola, Troglohyphantes konradi, Cicurina cicur, Tegenaria silvestris, Amaurobius, Duvalius carantii

TABLE CXIV.

Verrogne, Fessura del TABLE CXV. 360703E 5066012N 1536 m

TABLE CXVI.

Calcschist TABLE CXVII. ~2 TABLE CXVIII. Troglohyphantes TABLE CXIX.

lucifuga, Meta merianae, M. menardi TABLE CXX.

TABLE CXXII.

Figure 1. Temperature curves recorded inside the caves of Ghieisa and the Bandito.

TABLE CXXIII. JANUARY 2013 TEMPERATUREPARAMETERS, IN °C.

TABLE CXXIV. Cave TABLE CXXV. Entrance TABLE CXXVI. Inside TABLE CXXVIII. Distanc e fr o m en tra nc e TABLE CXXIX. Avera g e TABLE CXXX. TABLE CXXXI. Monthly ex cu rsi on TABLE CXXXII. Daily excursion (average) TABLE CXXXIII. Distanc e fr o m en tr an ce TABLE CXXXIV. Avera g e TABLE CXXXV. TABLE CXXXVI. Monthly ex cu rsi on TABLE CXXXVII. Daily excursion (average) TABLE CXXXVIII. Arenarie TABLE CXXXIX. 1 m TABLE CXL. 9.36 TABLE CXLI. 0.07 TABLE CXLII. 0.01 TABLE CXLIII. 70 m TABLE CXLIV. 9.14 TABLE CXLV. 0.03 TABLE CXLVI. 0.02 TABLE CXLVII. Argenter a TABLE CXLVIII. 1 m TABLE CXLIX. 0.86 TABLE CL. 2.33 TABLE CLI. 2.19 TABLE CLII. 11 m TABLE CLIII. 5.36 TABLE CLIV. 0.74 TABLE CLV. 0.97 TABLE CLVI. Bandito TABLE CLVII.

TABLE CLVIII. TABLE CLIX. TABLE CLX.

TABLE CLXI. 50 m TABLE CLXII. 8.56 TABLE CLXIII. 0.01 TABLE CLXIV. 0.01 TABLE CLXV. Bergovei TABLE CLXVI. 1 m TABLE CLXVII. 7.47 TABLE CLXVIII. 0.34 TABLE CLXIX. 0.08 TABLE CLXX. 150 m TABLE CLXXI. 10.40 TABLE CLXXII. 0.00 TABLE CLXXIII. 0.00 TABLE CLXXIV. Bossea TABLE CLXXV. 1 m TABLE CLXXVI. 4.32 TABLE CLXXVII. 0.93 TABLE CLXXVIII. 0.23 TABLE CLXXIX. 1700 m TABLE CLXXX. 8.88 TABLE CLXXXI. 0.02 TABLE CLXXXII. 0.03 TABLE CLXXXIII.

Caudano TABLE CLXXXIV. 2 m TABLE CLXXXV. 1.33 TABLE CLXXXVI. 1.25 0.48TABLE CLXXXVII. TABLE CLXXXVIII. 800 m TABLE CLXXXIX. 9.32 TABLE CXC. 0.00 TABLE CXCI. 0.00 TABLE CXCII. Custretta TABLE CXCIII. 1 m TABLE CXCIV. 0.37 TABLE CXCV. 2.20 TABLE CXCVI. 2.46 TABLE CXCVII. 50 m TABLE CXCVIII. 3.37 TABLE CXCIX. 1.06 TABLE CC. 0.24 TABLE CCI. Diau TABLE CCII.

TABLE CCIII. TABLE CCIV. TABLE CCV.

TABLE CCVI. 20 m TABLE CCVII. 5.62 TABLE CCVIII. 0.54 TABLE CCIX. 0.38 TABLE CCX. Diavolo TABLE CCXI. 1 m TABLE CCXII. 5.98 TABLE CCXIII. 0.69 TABLE CCXIV. 0.53 TABLE CCXV. 50 m TABLE CCXVI. 5.45 TABLE CCXVII. 0.29 TABLE CCXVIII. 0.07 TABLE CCXIX. Dronera TABLE CCXX.

TABLE CCXXI. TABLE CCXXII. TABLE CCXXIII.

TABLE CCXXIV. 80 m TABLE CCXXV. 10.43 TABLE CCXXVI. 0.00 TABLE CCXXVII. 0.00 TABLE CCXXVIII.

Ghiaccio TABLE CCXXIX. TABLE CCXXX. TABLE CCXXXI. TABLE CCXXXII. TABLE CCXXXIII. 20 m TABLE CCXXXIV. -0.50 TABLE CCXXXV. 0.35 TABLE CCXXXVI. 0.05 TABLE CCXXXVII. Ghieisa TABLE CCXXXVIII. 1 m TABLE CCXXXIX. 1.32 TABLE CCXL. 1.67 TABLE CCXLI. 1.83 TABLE CCXLII. 30 m TABLE CCXLIII. 2.88 TABLE CCXLIV. 0.86 TABLE CCXLV. 1.01 TABLE CCXLVI. Glace TABLE CCXLVII. 1 m TABLE CCXLVIII. -0.35 TABLE CCXLIX. 1.26 TABLE CCL. 0.55 TABLE CCLI. 20 m TABLE CCLII. -0.07 TABLE CCLIII. 0.68 TABLE CCLIV. 0.31 TABLE CCLV. Ivery TABLE CCLVI. 1 m TABLE CCLVII. 7.93 TABLE CCLVIII. 2.25 TABLE CCLIX. 1.51 TABLE CCLX.

TABLE CCLXI. TABLE CCLXII. TABLE CCLXIII. TABLE CCLXIV.

Maestro

TABLE CCLXV.

TABLE CCLXVI. TABLE CCLXVII. TABLE CCLXVIII.

TABLE CCLXIX. 17 m TABLE CCLXX. 5.67 TABLE CCLXXI. 0.64 TABLE CCLXXII. 0.23 TABLE CCLXXIII. Napoleo ne TABLE CCLXXIV. 1 m TABLE CCLXXV. 5.58 TABLE CCLXXVI. 0.90 TABLE CCLXXVII. 1.20 TABLE CCLXXVIII. 17 m TABLE CCLXXIX. 5.85 TABLE CCLXXX. 0.72 TABLE CCLXXXI. 0.43

TABLE CCLXXXII. Om Sal vej TABLE CCLXXXIII. 1 m TABLE CCLXXXIV. 5.37 TABLE CCLXXXV. 1.69 TABLE CCLXXXVI. 0.72 TABLE CCLXXXVII.

TABLE CCLXXXVIII. TABLE CCLXXXIX. TABLE CCXC. TABLE CCXCI.

Partigian o

TABLE CCXCII.

2 m TABLE CCXCIII.

4.23 TABLE CCXCIV. 0.87 TABLE CCXCV. 0.22

TABLE CCXCVI.

12 m TABLE CCXCVII.

6.01 TABLE CCXCVIII. 0.48 TABLE CCXCIX. 0.10 TABLE CCC. Pugnetto TABLE CCCI. 1 m TABLE CCCII. 2.38 TABLE CCCIII. 1.69 TABLE CCCIV. 1.50 TABLE CCCV. 500 m TABLE CCCVI. 9.34 TABLE CCCVII. 0.00 TABLE CCCVIII. 0.00 TABLE CCCIX. Servais TABLE CCCX.

TABLE CCCXI. TABLE CCCXII. TABLE CCCXIII.

TABLE CCCXIV. 12 m TABLE CCCXV. 5.54 TABLE CCCXVI. 0.87 TABLE CCCXVII. 0.41 TABLE CCCXVIII. Vernante TABLE CCCXIX.

TABLE CCCXX. TABLE CCCXXI. TABLE CCCXXII.

TABLE CCCXXIII. 50 m TABLE CCCXXIV. 8.59 TABLE CCCXXV. 0.15 TABLE CCCXXVI. 0.02 TABLE CCCXXVII. Verrogne TABLE CCCXXVIII. 2 m TABLE CCCXXIX. 3.12 TABLE CCCXXX. 0.88 TABLE CCCXXXI. 0.32 TABLE CCCXXXII. 15 m TABLE CCCXXXIII. 7.06 TABLE CCCXXXIV. 0.28 TABLE CCCXXXV. 0.09 TABLE CCCXXXVI.

To determine more accurately the position of the maximum

and the minimum of the thermic curve and have a better

estimate of the average and the annual thermic excursion, we

calculated with the method of least squares the equalization of

the thermic curve formed by daily data with the sine function

that follows.

T = T

+ E sint - t





where T is the temperature laid down in time t (expressed

in average of days since midnight 0.00 from 01/01/1900; the t

= 40988.63472 value corresponds to the spring equinox of

2012).

We thus obtain values:

T

, estimation of average temperature,

E, estimation of the annual excursion,

, estimation of the average time (in days) between the

summer solstice and the moment when the thermic curve

reaches the maximum value, and the average time between the

winter solstice and the moment where the thermic curve

reaches the minimum value. In other words, this parameter

indicates the "phase delay" of the position of the maxima and

minima of (1) compared to the solstices.

Table IV shows the parameters obtained from the

equalization of (1).

TABLE CCCXXXVII. VALUESOF JULY 2012 AND JANUARY 2013. ANNUALAVERAGEESTIMATED

BY JANUARYAND JULYVALUESMEDIATED.

TABLE CCCXXXVIII. TABLE CCCXXXIX.

Caves and position of the measurement TABLE CCCXL. TABLE CCCXLI. Average TABLE CCCXLII. Differen ce TABLE CCCXLIII. Annual average TABLE CCCXLIV. Standard deviation TABLE CCCXLV. Daily excursion TABLE CCCXLVII. Janu a r y TABLE CCCXLVIII. July TABLE CCCLI. Januar y TABLE CCCLII. July TABLE CCCLIII. Janu a r y TABLE CCCLIV. July TABLE CCCLV. Ghiaccio TABLE CCCLVI. -0.50 TABLE CCCLVII. 0.36 TABLE CCCLVIII. 0.86 TABLE CCCLIX. -0.07 TABLE CCCLX. 0.35 TABLE CCCLXI. 0.07 TABLE CCCLXII. 0.05 TABLE CCCLXIII. 0.03 TABLE CCCLXIV. Partigiano, inside TABLE CCCLXV. 6.01 TABLE CCCLXVI. 8.11 TABLE CCCLXVII. 2.11 TABLE CCCLXVIII. 7.06 TABLE CCCLXIX. 0.48 TABLE CCCLXX. 0.07 TABLE CCCLXXI. 0.10 TABLE CCCLXXII. 0.02 TABLE CCCLXXIII. Partigiano, entrance TABLE CCCLXXIV. 4.23 TABLE CCCLXXV. 8.82 TABLE CCCLXXVI. 4.59 TABLE CCCLXXVII. 6.53 TABLE CCCLXXVIII. 0.87 TABLE CCCLXXIX. 0.16 TABLE CCCLXXX. 0.22 TABLE CCCLXXXI. 0.02 TABLE CCCLXXXII. Argentera, inside TABLE CCCLXXXIII. 5.36 TABLE CCCLXXXIV. 10.59 * TABLE CCCLXXXV. 5.23 TABLE CCCLXXXVI. 7.97 TABLE CCCLXXXVII. 0.74 TABLE CCCLXXXVIII. 0.63* TABLE CCCLXXXIX. 0.97 TABLE CCCXC. 0.61 TABLE CCCXCI. Argentera, entrance TABLE CCCXCII. 0.86 TABLE CCCXCIII. 11.93 * TABLE CCCXCIV. 11.07 TABLE CCCXCV. 6.40 TABLE CCCXCVI. 2.33 TABLE CCCXCVII. 0.66* TABLE CCCXCVIII. 2.19 TABLE CCCXCIX. 0.98 TABLE CD. Bandito TABLE CDI. 8.56 TABLE CDII. 8.63 TABLE CDIII. 0.07 TABLE CDIV. 8.60 TABLE CDV. 0.01 TABLE CDVI. 0.00 TABLE CDVII. 0.01 TABLE CDVIII. 0.00 TABLE CDIX. Vernante TABLE CDX. 8.59 TABLE CDXI. 8.94 TABLE CDXII. 0.35 TABLE CDXIII. 8.76 TABLE CDXIV. 0.15 TABLE CDXV. 0.08 TABLE CDXVI. 0.02 TABLE CDXVII. 0.03 TABLE CDXVIII. Bossea, inside TABLE CDXIX. 8.88 TABLE CDXX. 9.01* * TABLE CDXXI. 0.14 TABLE CDXXII. 8.94 TABLE CDXXIII. 0.02 TABLE CDXXIV. 0.02* * TABLE CDXXV. 0.03 TABLE CDXXVI. 0.02 TABLE CDXXVII. Bossea, entrance TABLE CDXXVIII. 4.32 TABLE CDXXIX. 15.29 * * TABLE CDXXX. 10.97 TABLE CDXXXI. 9.80 TABLE CDXXXII. 0.93 TABLE CDXXXIII. 0.65* * TABLE CDXXXIV. 0.23 TABLE CDXXXV. 0.58 TABLE CDXXXVI.

Caudano, inside TABLE CDXXXVII. 9.32 TABLE CDXXXVIII. 9.38 TABLE CDXXXIX. 0.06 9.35TABLE CDXL. TABLE CDXLI. 0.00 TABLE CDXLII. 0.00 TABLE CDXLIII. 0.00 TABLE CDXLIV. 0.00 TABLE CDXLV. Caudano, entrance TABLE CDXLVI. 1.33 TABLE CDXLVII. 8.23 TABLE CDXLVIII. 6.90 TABLE CDXLIX. 4.78 TABLE CDL. 1.25 TABLE CDLI. 0.09 TABLE CDLII. 0.48 TABLE CDLIII. 0.15

Pugnetto, inside 9.34 9.40 0.06 9.37 0.00 0.00 0.00 0.01 TABLE CDLXIII. Pugnetto, entrance TABLE CDLXIV. 2.38 TABLE CDLXV. 7.76 TABLE CDLXVI. 5.38 TABLE CDLXVII. 5.07 TABLE CDLXVIII. 1.69 TABLE CDLXIX. 0.20 TABLE CDLXX. 1.50 TABLE CDLXXI. 0.06 TABLE CDLXXII. Napoleone, inside TABLE CDLXXIII. 5.85 TABLE CDLXXIV. 13.82 TABLE CDLXXV. 7.97 TABLE CDLXXVI. 9.84 TABLE CDLXXVII. 0.72 TABLE CDLXXVIII. 0.46 TABLE CDLXXIX. 0.43 TABLE CDLXXX. 1.00 TABLE CDLXXXI.

Napoleone, entrance TABLE CDLXXXII. 5.58 TABLE CDLXXXIII. 18.68 TABLE CDLXXXIV. 13.10 12.13TABLE CDLXXXV. TABLE CDLXXXVI. 0.90 TABLE CDLXXXVII. 0.76 TABLE CDLXXXVIII. 1.20 TABLE CDLXXXIX. 0.96 TABLE CDXC. Dronera TABLE CDXCI. 10.43 TABLE CDXCII. 10.80 * * TABLE CDXCIII. 0.37 TABLE CDXCIV. 10.61 TABLE CDXCV. 0.00 TABLE CDXCVI. 0.01* * TABLE CDXCVII. 0.00 TABLE CDXCVIII. 0.01

TABLE CDXCIX. *) Values are only the first 15 days of the 2013.

TABLE D. **) Values that relate only to the third decade.

TABLE DI.

TABLE DII. VALUESOF TM, E,.

TABLE DIII. *) Values that exceed 365.2422, mean tropical year.

IV.

D

Thermic characteristics of the investigated caves show

remarkable differences between a cave and the other.

A.

Daily oscillations

Examined hypogeous environments have daily excursions

already very low at the entrance and almost nil in the big caves

at a depth of some dozen of meters (tab. II). in this respect it

should be noted that values in twilight zone of big caves are

comparable with the values of the inside of shorter caves.

The variability of conditions in the course of the month is

linked to external weather changes and is much reduced in

hypogeal environment. The evidence is the relatively low

standard deviation of the data at monthly scale (table II).

TABLE I.

Cave TABLE II. Distance from entrance TABLE III. Tm

TABLE IV. E TABLE V.  TABLE VI. Bossea TABLE VII. 1700 m TABLE VIII. 8.90 TABLE IX. 0.10 TABLE X. 420.2* TABLE XI. Caudano TABLE XII. 800 m TABLE XIII. 9.34 TABLE XIV. 0.07 TABLE XV. 366.7* TABLE XVI. Pugnetto TABLE XVII. 500 m TABLE XVIII. 9.39 TABLE XIX. 0.12 TABLE XX. 339.5 TABLE XXI. Bergovei TABLE XXII. 150 m TABLE XXIII. 10.40 TABLE XXIV. 0.02 TABLE XXV. 166.0 TABLE XXVI.

Dronera TABLE XXVII. 80 m TABLE XXVIII. 10.58 TABLE XXIX. 0.58 TABLE XXX. 68.0 TABLE XXXI. Arenarie TABLE XXXII. 70 m TABLE XXXIII. 9.09 TABLE XXXIV. 0.20 TABLE XXXV. 170.0 TABLE XXXVI. Diavolo TABLE XXXVII. 50 m TABLE XXXVIII. 6.14 TABLE XXXIX. 2.91 TABLE XL. 87.7 TABLE XLI. Bandito TABLE XLII. 50 m TABLE XLIII. 8.59 TABLE XLIV. 0.13 TABLE XLV. 62.1 TABLE XLVI. Vernante TABLE XLVII. 50 m TABLE XLVIII. 8.86 TABLE XLIX. 2.17 TABLE L. 103.1 TABLE LI.

Custretta TABLE LII. 50 m TABLE LIII. 5.14 TABLE LIV. 6.36 TABLE LV. 72.1

TABLE LVI. Ghieisa TABLE LVII. 30 m TABLE LVIII. 7.57 TABLE LIX. 12.47 TABLE LX. 58.1 TABLE LXI. Diau TABLE LXII. 20 m TABLE LXIII. 7.93 TABLE LXIV. 6.85 TABLE LXV. 67.9 TABLE LXVI. Glace TABLE LXVII. 20 m TABLE LXVIII. 3.39 TABLE LXIX. 10.13 TABLE LXX. 60.8 TABLE LXXI. Ghiaccio TABLE LXXII. 20 m TABLE LXXIII. 7.57 TABLE LXXIV. 12.47 TABLE LXXV. 101.5 TABLE LXXVI. Napoleon e TABLE LXXVII. 17 m TABLE LXXVIII. 10.07 TABLE LXXIX. 10.64 TABLE LXXX. 61.8 TABLE LXXXI. Maestro TABLE LXXXII. 17 m TABLE LXXXIII. 8.71 TABLE LXXXIV. 8.10 TABLE LXXXV. 64.5 TABLE LXXXVI.

Verrogne TABLE LXXXVII. 15 m TABLE LXXXVIII. 8.14 TABLE LXXXIX. 4.52 TABLE XC. 92.3 TABLE XCI. Partigiano TABLE XCII. 12 m TABLE XCIII. 7.15 TABLE XCIV. 3.77 TABLE XCV. 78.0 TABLE XCVI. Servais TABLE XCVII. 12 m TABLE XCVIII. 7.51 TABLE XCIX. 5.38 TABLE C. 55.8 TABLE CI. Argentera TABLE CII. 11 m TABLE CIII. 7.57 TABLE CIV. 6.28 TABLE CV. 75.4

The causes that reduce this variability are almost the same

of those that depress daily excursions: this explains the good

linear correlation between the two variables (fig. 2).

The caves whose temperature exceeds 9 °C (Pugnetto,

Testa di Napoleone, Dronera) have highest daily temperature in

July than in January, while the same caves at the entrance and

the caves whose temperature is < 9° show both the opposite

phenomenon. Bossea cave is the only exception, but it has the

average temperature that exceeds around 9 °C at the entrance

as inside.

Caves with more stable thermic conditions are no

exceptions to this rule, even if they have, as already mentioned,

daily thermic excursions very low. This phenomenon is not

simply a consequence of variability in thermic conditions: the

standard deviation data is usually higher in January than in

July, although in July the daily excursion is higher that in

January (unique exception, Tana della Dronera, perhaps

because it is an active resurgence which in summer is thin or

dry).

B.

Annual oscillations

The caves examined, especially those longer and deeper,

are an insulated environment where temperature changes, even

at annual level (over the year) occur very attenuated and with

great delay. However, the annual thermic excursions vary

greatly. Inside the large caves we refer to less than 1 °C

(Bergovei, Bossea, Bandito, Pugnetto, and Dronera). We found

the smallest excursion in the largest and most long cave: that of

Caudano, with a value of 0.07 °C. But the annual excursion can

exceed 10 °C, even inside, in the caves as smaller or shallower

(Testa di Napoleone, Glace, Ghiaccio). There is no correlation

between the average temperature and annual thermic excursion.

Figure 2. Relationship

between average daily thermic excursion and the standard deviation of the daily temperatures in January 2013 (°C).

V.

P

P

We can subdivide the caves studied in four groups on the

basis of their thermic condition inside (tab. V).

TABLE DIV.

GROUPSOFTHERMICCONDITIONSOFTHECAVES.

Group Caves Averages Daily excursions Annual excursions A Bergovei, Caudano, Bossea, Bandito, Arenarie, Dronera, Pugnetto 8.5 - 10.5 °C Very very weak or absent (< 0.05 °C) Very weak (< 0.6 °C) B Vernante, Diavolo, Partigiano 6 – 9 °C Very weak (0.02 - 0.10 °C) Weak (2 - 5 °C) C Servais, Argentera, Maestro, Napoleone 7.5 - 10.5 °C Variable (0.20 - 1.00 °C) Relatively high (5 - 13 °C) D Custretta, Glace, Ghiaccio 3 – 8 °C T < 0 °C in January Moderate (0.05-0.35 °C) Relatively high (5 - 13 °C)

Thermic conditions of Group A (the part with the

troglobites) are almost stable over time, on a daily scale

(excursions < 0.05 ° C), as on an annual scale (excursions < 0.6

° C).

The caves of Group B conditions are not large, but are well

isolated from the external environment: the annual and daily

thermic excursions are very limited.

The caves entirely in Group C conditions are small: so,

temperatures are quite similar to those at the entrance of the

larger caves, which is characterized by poor thermic insulation.

It is for this that the daily excursion is bigger, from moderate

(for a cave environment, i.e. 0.2 ° C) to high (~ 1 ° C) and

annual thermic excursions are relatively high. Being altitude

low, there is not any phenomenon of freezing / melting, which

is a factor of temperature stabilization.

Also the caves of Group D conditions are small. They are

high altitude (on the contrary of Group C), so in January they

normally contain ice [1]. The thermic effect of phase changes

of water moderates daily thermic excursions while annual

thermic excursions remain relatively high. Because of this, the

daily temperature range is smaller than those of the third group

(0.05-0.35° C).

Also the "phase delay" well characterizes these groups (tab.

VI). We observe that, despite their low values of the annual

thermic excursion (E), the value of the Grotta del Bandito is

only of 62.1 days. Also the value of the Dronera (68.0 days)

seem be anomalous. So, the group A shows a very large range

of values.

TABLE DV.

THE "PHASEDELAY" () INTHEGROUPSOFTAB. V.

Group Caves (days) A Bergovei, Caudano, Bossea, Bandito, Arenarie,_Dronera 62.1- 420.2

B Vernante, Diavolo, Partigiano 78.1 - 103.1

C Servais, Argentera, Maestro, Napoleone 55.8 - 75.4

D Custretta, Glace, Ghiaccio 60.8 - 101.5

R

[1] AGSP, Atlante delle grotte e delle aree carsiche piemontesi. Torino: AGSP and Regione Piemonte, 1995.

[2] Arnò C. and E. Lana, Ragni cavernicoli del Piemonte e della Valle d’Aosta. Torino: AGSP and Regione Piemonte, 2005.

[3] Isaia M., Paschetta M., Chiarle A., Badino G., Berto S., Bona F., Meregalli M., Motta M., Motta L., Vione D. and A. Vizzini, "CAVELAB, an interdisciplinary research project for the study of cave ecosystems and their potentialities for the study of global change", Abstract Book, Thungai University, Thaichung, pp. 201-202, 2013. [4] Lana E., Biospeleologia del Piemonte. Torino: AGSP and Regione