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Catena 65 (200

Phosphorus content in five representative landscape units of the Lomas de

Arequipa (Atacama Desert-Peru)

Andre Fabre a,*, Thierry Gauquelin a, Francisco Vilasante b, Aldo Ortega b, Henri Puig a

a Laboratoire Dynamique de la Biodiversite, 29 Rue Jeanne Marvig, 31055 Toulouse Cedex, Franceb Universidad Nacional San Augustin, Instituto Regional de Ciencias Ambientales, Casilla 985, Arequipa, Peru

Received 27 September 2004; received in revised form 21 September 2005; accepted 12 October 2005

Abstract

Phosphorus forms and content were studied in soils of the Lomas de Arequipa (Atacama desert, Peru) using a fractionation method. These

Lomas are small hills periodically submitted to the El Nino-Southern Oscillation (ENSO) which causes heavy rainfall. Sample soils were

randomly selected in five landscape types characterized by vegetation: cactaceae (Cac), cactaceae and herbaceous (CacHerb), shrubs (Shr),

trees with cover <60% (Tree) and shrubs or trees with cover >60%) (ShrTree). All the soils were strongly acidic and classified as loamy sand,

sandy loam or silt loam. Organic carbon content was under 1% in Cac or CacHerb, then increased strongly in ShrTree (6.50%). Considering

phosphorus, all the forms (labile as well resistant forms) increased markedly from Cac soils to ShrTree soils. In all the soils, the labile forms

(Resin-P: range 45–105 Ag g�1; NaHCO3-Pi: 23–123 Ag g�1; or NaHCO3-Po: 10–122 Ag g�1) were very high. These high phosphorus

contents were attributed to the specific climatic conditions of the Lomas that feature a long period of vegetation dormancy (very dry period)

and a short period of growth, following ENSO-associated precipitation. We suggested that during the dry period, plant decay and microbial

cells death lead to release and accumulation of labile P in the soil, the rainfall wetting the soil, permitting vegetation growth. In this respect,

the Lomas climatic conditions contribute to soil fertility, especially as labile forms of phosphorus are chiefly concerned.

D 2005 Elsevier B.V. All rights reserved.

Keywords: Soils; Phosphorus fractionation; Lomas; Peru; ENSO; Atacama desert

1. Introduction

Coastal deserts such as Atacama (Coastal Peruvian desert

continued by the Northern Chilean desert) present specific

characteristics: a) they are the driest among all deserts; b) the

general climate is mild and uniform; c) the temperature is

fairly evenly distributed throughout the year; d) they are

subject to winter fogs. These climatic conditions impart to

coastal arid regions unique characteristics compared to arid

regions characterised by high mean and large amplitude

temperature. The aridity results from several combined

factors, especially the permanent high pressure area over

the Pacific Ocean and atmospheric stability induced by the

cold northward flowing Humboldt Current. This cold current

makes the air become cool or cold but dry and very stable

0341-8162/$ - see front matter D 2005 Elsevier B.V. All rights reserved.

doi:10.1016/j.catena.2005.10.004

* Corresponding author.

E-mail address: acfabre@aol.com (A. Fabre).

overall, unable to produce precipitation. At the same time,

there is very little evaporation and humidity is confined to a

low level, giving persistent haze. Whereas mist may occur

any time throughout the year, there are some particularly

foggy periods, generally at the end of the austral winter and in

early spring (Zavala Yupanqui, 1993). Along the Chilean and

Peruvian coasts, elevations between 600 and 1000 m are the

most favourable for fog formation (Osses McIntyre, 1996).

The Atacama desert is strongly affected by El Nino

(disruption of the ocean–atmosphere system in the Tropical

Pacific with consequences for weather around the globe)

which generates abundant rainfall. El Nino-Southern Oscil-

lation (ENSO) is a coupled ocean-atmosphere phenomena

that has a worldwide impact on climate.

ENSO, which seems to occur with a cyclic rhythm in

coastal Peru (every 10 years on average) induces excep-

tional rainfall in these regions. However, since the nineties,

ENSO has occurred every 2 to 7 years. The last very rainy

6) 80 – 86

Fig. 1. Study site location.

A. Fabre et al. / Catena 65 (2006) 80–86 81

periods occurred in 1982, 1992 and 1997–1998. In several

parts of the Atacama desert as in the Arequipa region (South

Peru), the coast is dominated by low hills (elevation varying

from some hundred to about 1200 m) termed ‘‘Lomas’’ in

Spanish (geomorphological sense). The same term refers to

the fog caught on these hills (climatic sense) and to the

vegetation arising during the foggy season (phytological

sense). In the following text, the term Lomas is used in the

global sense, comprising all three of these notions.

The vegetation is composed of numerous ephemeral but

also of perennial species, ligneous plants and cactaceae.

Some studies have been published on the Peruvian Lomas

(Pefaur, 1982; Ferreyra, 1993).

The Lomas are utilized for forage and to gather woody

species for fuelwood (Ferreyra, 1977). They are periodically

used for grazing livestock (cattle, sheep and goats), especially

during ENSO events, and possibly as grazing land during

seasonal livestock migration during the Spanish period.

Considering the soils of deserts, studies are scarce and

mainly concern hot deserts or arid ecosystems (Lajtha,

1988; Lajtha and Schlesinger, 1988; Cross and Schlesinger,

2001). At the moment, no information exists on the soil

characteristics of the Atacama desert or of the Lomas. In this

paper we consider some general soil characteristics and we

emphasize the different forms of phosphorus in soils of five

representative vegetation types (Lomas types) of Lomas de

Arequipa (South Peru, Fig. 1). Hypothesis of a close

relationship between labile phosphorus content in the soils

and ENSO events inducing exceptional rainfall is discussed.

2. Materials and methods

2.1. Study site

The study site was situated near the town of Mollendo, in

the Arequipa region, on the south Peruvian coast (72-10–

71-40V W; 16-90V–17-40 S). In this region, average annual

precipitation is only <50 mm below 500 m alt. and several

years may pass without rainfall. The driest period occurs

from January–February to April. From May to October,

heavy fog (relative air humidity near 75%) permits

vegetation growth. The average annual temperature is

around 18 -C and the annual variation in temperature is

small with a minimum of 9–12 -C in July and a maximum

of 25 -C in January–February (Zavala Yupanqui, 1993).

When the coastal topography is flat, the seasonal fog

dissipates inland but where isolated hills (150 to 1000 m)

intercept the fog, a fog zone appears allowing the develop-

ment of rich vegetation termed ‘‘Lomas formations’’ sepa-

rated by areas without vegetation. In Peru, around 40 Lomas

formations exist, among them the Lomas de Mollendo.

The bedrock is acid igneous (granodiorite) with local

clastic sediments (sand, clay, sandstone or conglomerates).

The non-consolidated parent material (particles <2 mm)

pertains to the loamy or sandy texture groups. The soils are

in the Aridisols class characterized by low organic carbon.

2.2. Soil sampling

Using SPOT images (SPOT 661–384; July 1995) and

aerial photography, 8 different landscape types were

identified in the Arequipa region. Five of them were

retained in this study: cover dominated by cacti (Cac), by

cacti and herbaceous (CacHerb), by shrubs (Shr), by trees

with percentage cover <60% (Tree), and by shrubs and trees

with percentage cover >60% (ShrTree). The distinction

between these landscape types resulted from a site

vegetation study (120 sample plots of vegetation statistically

analysed using correspondence analysis). Some dominant

species are listed in Table 1. In each type, 4 sampling areas

were randomly selected using a grid. However, as in desert

landscapes, the vegetation strongly influences soil nutrient

content, soil samples were randomly selected, after elimi-

nating nearness of vegetation patches. Soil samples were

taken in the first 5 cm after discarding the litter when

necessary. They were stoney, particularly in Cac and

CacHerb. The soil samples were stored for grain size and

chemical analysis. Sampling and vegetation studies were

performed during September 1997, before a rainy period.

2.3. Chemical analyses

Soil samples were analysed for grain size, pH in water,

organic carbon using CHN auto analyser, and different forms

of phosphorus. Sand, silt and clay percentage were estimated

using the pipette method and the soil texture classes were

determined using the Soil Science Society of America chart.

Total phosphorus was fractionated using a sequential

extraction method (Hedley et al., 1982). The sequential

extraction removed inorganic P (Pi) and organic P (Po) of

increasing chemical stability with different geochemical or

ecological significance. First, the most labile inorganic

Table 1

Floristic composition of each Lomas type

Lomas type Altitude

(range)

% Plant

cover

Some dominant species

Cacti 160–680 1–3 Neoraimundia arequipensis, Borzicactus sp., Islaya mollendoensis, Trichocereus sp.,

Neoporteria islayensis, Tephrocactus sp., Pilocereus sp.

Cacti and herbaceous 620–790 2–10 Neoraimundia arequipensis, Borzicactus sp., Islaya mollendoensis, Tichocereus sp.,

Neoporteria islayensis, Tephrocactus sp.

Eragrostis peruviana, Cotula australis, Tillandsia sp., Poa sp., Urocarpidium sp., Atriplex sp.

Shrubs 620–850 20–35 Phylla nodiflora, Citharexylum flexuosum, Grindelia glutinosa, Croton ruizianus,

Heliotropium lanceolatum, Vigueria weberbaueri, Lycopersicum peruvianum,

Urocarpidium peruvianum, Cotula australis

Trees (cover <60%) 620–690 10–50 Caesalpinia spinosa, Duranta armata, Heliotropium arborescens

Shrubs or trees

(cover >60%)

690–980 75–100 Caesalpinia spinosa, Duranta armata, Heliotropium arborescens, Phylla nodiflora,

Citharexylum flexuosum, Grindelia glutinosa, Croton ruizianus, Heliotropium lanceolatum,

Vigueria weberbaueri, Lycopersicum peruvianum

A. Fabre et al. / Catena 65 (2006) 80–8682

phosphorus was extracted using an anion exchange resin

(Resin-P) (Amer et al., 1955). Sodium bicarbonate 0.5 M

(pH 8.5) removed labile Pi (NaHCO3-Pi) and Po (NaHCO3-

Po) sorbed to the soil surfaces (Bowman and Cole, 1978a,b).

NaHCO3-Po is easily mineralizable and can contribute to

plant available P. Sodium hydroxide 0.1 M extracted Pi

(NaOH-Pi) associated with amorphous and some crystalline

Al and Fe oxides (Syers et al., 1969) and Po associated with

humic compounds (NaOH-Po) (Fares et al., 1974). NaOH-Pi

is relatively labile Pi (Bowman and Cole, 1978a,b) while

NaOH-Po is considered to be involved in long term

transformation of soil under temperate climates (Tiessen et

al., 1983). Resin-P, NaHCO3-Pi, NaOH-Pi, NaHCO3-Po and

NaOH-Po are considered as non-occluded forms (Walker

and Syers, 1976). Phosphorus extracted with 1M hydro-

chloric acid (HCl-P) is mainly apatitic phosphorus. It is

unavailable in the short term. The residue containing the

most chemically stable Po and Pi forms was digested using

concentrated H2SO4+H2O2 (Resid-P) (Thomas et al., 1967).

Extracts containing organic phosphorus were digested for

total P determination using a persulfate digestion method

(Standard Methods, 1971). Phosphorus in the extracts or

digests was determined after pH adjustment if necessary,

using the ascorbic acid molybdenum blue method. A

literature review of the Hedley P fractionation method was

performed by Cross and Schlesinger (1995). All the chemical

results were expressed on air dried basis.

2.4. Statistical methods

All the statistical analyses were performed using Systat

8.0 software. Analysis of variance was used to compare P

Table 2

General characteristics of the soil for each Lomas type (4 replicates in each Lom

Lomas type pH % Organic C % C

Cacti 4.9T0.21 0.34T0.28 2.1

Cacti and herbaceous 4.5T0.19 0.68T0.16 6.1

Shrubs 5.0T0.19 1.45T0.38 7.5

Trees (cover <60%) 4.6T0.15 2.40T0.47 11.2

Shrubs and trees (cover >60%) 4.7T0.27 6.50T0.42 12.7

contents between landscape types. When global ANOVA p

value was <0.05, the Bonferroni post hoc test was

performed to determine which pairs of means differ

significantly.

3. Results

3.1. General characteristics

The mean pH values (Table 2) were not significantly

different between stands. They were very acid (pH around

4.7). All the soils were very poor in clay (range 2.1–12.7%)

and presented large variability concerning silt and sand

(range 11.0–60.8 and 26.5–87.0%, respectively). The soils

were classified as loamy sand, sandy loam or silt loam. Cac

stands were very rich in sand content (87.0%) and very poor

in clay (2.1%). Inversely, Tree and especially ShrTree were

the richest in clay content (11.2% and 12.7%, respectively).

Organic carbon contents were under 1% in Cac and

CacHerb. Then they increased in Shr and Tree (1.45% and

2.40%, respectively) and above all in the ShrTree stands

(6.50%).

3.2. Phosphorus contents

Considering the sum of the fractions (Table 3), Cac

presented the lowest value (448.1 Ag g-1) and ShrTree the

highest value (962.8 Ag g�1). The three other stands were not

significantly different (P >0.05). Resin-P varied from

44.7 Ag g�1 in the Cac stands to 104.5 Ag g�1 in the

ShrTree stands. These values are significantly different from

as type)

lay % Silt % Sand Soil textural classes

T0.71 11.0T3.42 87.0T4.10 Loamy sand

T0.37 39.0T3.64 54.9T3.97 Loamy sand sandy loam

T0.33 59.2T1.07 33.4T1.38 Silt loam

T0.85 59.3T 29.8T2.49 Silt loam

T0.83 60.8T2.08 26.5T2.87 Silt loam

Table 3

Concentration of forms of phosphorus (Ag g�1)

Lomas type Resin-P NaHCO3-Pi NaHCO3-Po NaOH-Pi NaOH-Po HCl-P Residual-P Sum of the fractions

Cacti 44.7T4.6

(10.0)

23.4T4.3

(5.2)

10.4T2.5

(2.3)

33.4T5.6

(7.5)

22.1T4.9

(4.9)

267.3T5.1

(59.7)

47.0T3.9

(10.5)

448.1T13.0

Cacti and herbaceous 78.1T6.1(12.5)

33.4T2.7(5.3)

76.6T6.0(12.3)

72.0T11.5(11.5)

9.8T1.9(1.6)

297.8T2.7(47.7)

57.2T10.8(9.2)

624.8T23.1

Shrubs 78.9T6.2

(9.9)

122.9T4.3

(15.5)

62.4T3.4

(7.8)

70.9T4.8

(8.9)

27.4T5.5

(3.4)

386.3T35.2

(48.6)

46.2T7.7

(5.8)

795.0T39.4

Trees (cover <60%) 81.6T6.7(10.8)

109.9T7.9(14.5)

84.9T5.3(11.2)

94.8T7.0(12.5)

49.9T4.8(6.6)

256.4T27.8(33.9)

79.8T6.2(10.5)

757.2T53.3

Shrubs or trees

(cover >60%)

104.5T2.9

(10.9)

92.3T7.1

(9.6)

122.4T3.5

(12.7)

125.1T13.2

(13.0)

139.3T4.3

(14.5)

136.4T16.3

(14.2)

242.8T10.4

(25.2)

962.8T40.1

Mean values and standard error of the mean (n =4). In brackets, percentage of the sum of the fractions.

A. Fabre et al. / Catena 65 (2006) 80–86 83

Resin-P contents in the other stands which did not present

significant differences between each other. NaHCO3-Pi

contents were lowest in Cac or CacHerb (23.4 and 33.4 Agg�1, respectively) and differed significantly with ShrTree,

Tree and Shr (92.3, 109.9 and 122.9 Ag g�1, respectively),

themselves being not significantly different. NaHCO3-Po

varied from 10.4 (Cac) to 122.4 Ag g�1 (ShrTree). These

contents were significantly different from the three other

stands which were not significantly different between each

other (range 62.4–84.9 Ag g�1). NaOH-Pi contents were

significantly different between Cac (33.4 Ag g�1) and

ShrTree (125.1 Ag g�1). The three other stands presented

intermediate values (range 70.9–94.8 Ag g�1). NaOH-Po

presented the lowest values in Cac, CacHerb and Shr (not

significantly different; range 9.8–27.4 Ag g�1) contrasting to

the content in ShrTree (139.3 Ag g�1). The content in Tree

(49.9 Ag g�1) was significantly different from the other

stands. HCl-P opposed a low content in ShrTree (136.4 Agg�1) to the other stands (range 256.4–386.3 Ag g�1). Resid-

P markedly opposed ShrTree stand (242.8 Ag g�1) to the

other stands (range 47.0–79.8 Ag g�1).

3.3. Relations between soil parameters

Organic carbon was positively correlated (r =0.90) with

%cover (Table 4). Except on HCl-P and Resid-P, all the other

forms of phosphorus are significantly positively correlated

Table 4

Correlation matrix between phosphorus forms and related parameters (in bold ch

Resin P NaHCO3 Pi NaHCO3 Po NaOH Pi NaOH Po H

Resin P

NaHCO3 Pi 0.53

NaHCO3 Po 0.89 0.50

NaOH-Pi 0.78 0.55 0.87

NaOH-Po 0.65 0.36 0.71 0.74

HCl-P �0.33 0.08 �0.47 �0.41 �0.72

Residual P 0.65 0.24 0.74 0.79 0.96 �% Organic C 0.68 0.38 0.76 0.76 0.96 �Altitude 0.73 0.47 0.73 0.70 0.55 �% Cover 0.75 0.51 0.73 0.79 0.93 �% Clay 0.82 0.66 0.88 0.89 0.75 �% Silt 0.77 0.83 0.81 0.76 0.51 �% Sand �0.79 �0.81 �0.83 �0.79 �0.56

with %clay or %silt or both, and negatively correlated with

%sand. Likewise, except on NaHCO3-Pi or HCl-P, all the P

forms were positively correlated with %cover.

4. Discussion

4.1. Carbon content

The high correlation between organic carbon and

vegetation cover has already been shown in several studies

in arid areas (Le Houerou, 1986; Gauquelin et al., 1998).

Nevertheless we can notice the high organic carbon content

(around 6.50%) of the soils of the ShrTree stands, generally

situated in the upper part of the Lomas, where the

percentage of plant coverage is high (>75%).

4.2. Phosphorus content

In all the soils, we found high labile P contents (Resin-P,

NaHCO3-Pi and Po), in comparison with data from other

arid or desert soils. Nevertheless, comparisons with litera-

ture data are difficult because most of these data concern hot

arid areas or deserts not periodically exposed to intense

rainy periods (ENSO events). The high concentrations of the

different forms of P in the Lomas can be ascribed to the

combination of different and independent effects (Fig. 2).

aracter: statistical significance at P <0.05 level)

Cl P Residual P % Organic C Altitude % Cover % Clay % Silt

0.73

0.67 0.93

0.06 0.51 0.66

0.60 0.91 0.90 0.61

0.41 0.71 0.80 0.78 0.80

0.08 0.44 0.61 0.81 0.62 0.88

0.14 �0.49 �0.65 �0.82 �0.66 �0.92 �0.99

Fig. 2. Mechanism of distribution of soil phosphorus in the Lomas de Arequipa: flowchart.

A. Fabre et al. / Catena 65 (2006) 80–8684

4.2.1. Land use and grazing effect

Since the Spanish colonization, the Lomas has been

grazed by sheep, goats and cattle. Nowadays, the Lomas are

still grazed, especially during ENSO events and are used as

a fuelwood source. Livestock foraging is important in

pasture nutrient cycling because they convert nutrients from

unavailable forms (natural fodder) to available forms

(excreta) (Buschbacher, 1987). Moreover, the constant

movement of the animals leads to a relatively regular

distribution of faeces through the patchy landscape (Turner,

1998).

4.2.2. ENSO events

During ENSO events, seeds lying within the soil,

germinate and emerge into a continuous blanket. Then, this

vegetation dies and decays quickly. In temperate or tropical

ecosystems, many studies have shown that the different

forms of P, and especially the more labile, present seasonal

fluctuations. Generally, the more labile forms of P increase

during winter and decrease during the growing season

(Timmons et al., 1970; Saunders and Metson, 1971;

Dormaar, 1972; Vaughan et al., 1986; Sarathchandra et al.,

1989; Perrott et al., 1990; Magid and Nielsen, 1992).

Likewise, in a mature tropical moist forest, inorganic P

peaks during the dry season (Yavitt and Wright, 1996).

These findings suggest that during the dormant vegetation

season (winter or dry season) there is an increase and

accumulation of the more labile P forms.

Considering the mechanism, the literature yields

conflicting reports. Some authors consider that accumula-

tion of labile P results on the microbial mineralization of

plant debris or to the release of Pi from the organic matter

(Saunders and Metson, 1971). Others attribute the labile P

increase to the microbial biomass killed by air-drying

(Srivastava, 1997). Using New Zealand acid soils, Haynes

and Swift (1985) showed that drying soils increased

phosphate extractable with EDTA, resin or NaHCO3 and

considered that drying soil conducive to the release of P

associated with organic matter—Fe and Al complexes, and

possibly from killed microbial cells. Similarly, Sparling et

al. (1985), studying 18 pasture soil samples from New

Zealand, showed that, in most of the soils investigated,

drying led to an increase of NaHCO3-Pi. Williams (1996)

showed that a greater concentration of P leached by CaCl2,

extracted from spruce or pines humus, coincided with

drying of the soil during summer. He considered that the

enhanced Pi contents in the dried soils can be mainly

accounted for by the release of Pi from the killed cells or to

death of fine roots and microorganisms and concluded that a

rainy period following a dry period, could contribute to

plant growth following rewetting. In this respect a period of

soil drying could benefit overall fertility levels.

A. Fabre et al. / Catena 65 (2006) 80–86 85

Foliar or plant residue or litter leaching is generally

considered as a source of labile-P (Timmons et al., 1970;

Bromfield and Jones, 1972; Duffy et al., 1985; Johnson and

Todd, 1987; Weiss et al., 1991; Polglase et al., 1992). In the

Lomas, at the end ENSO-related rainfall, and during

the beginning of the dry period, death and decay of the

vegetation (especially the ephemerals), possibly causes the

release and accumulation of labile P permitting the P pool to

be rebuilt. During the dry period, this pool is not used by the

seeds and the vegetation is dormant.

4.2.3. Particle size distribution

The distribution of the vegetation from Cac to ShrTree

from near 160 to 980 m of altitude can be considered as a

toposequence. Generally, in a toposequence, erosional

processes bring about enrichment in fine particles from the

top to the bottom of the relief. In the Lomas, we found the

reserve with a higher fine particles content in soil from the

upper part of the landscape (Table 2). This can be ascribed to

the increasing percentage plant cover from Cac (lower part)

to TreeShr stands (upper part) where canopy and litter reduce

erosion processes. The result is an increasing content of P

labile forms from the lower to the upper part of the landscape

corresponding to the general association between labile P

and the finest soil particles. A positive relation between the

finest soil particles and labile P was shown in cultivated and

uncultivated soils (Tiessen et al., 1983) or with algal

available P or P sorption in eutrophication studies (Syers et

al., 1969; Dorich et al., 1984; Keulder, 1982). Nevertheless,

in a toposequence from semiarid northeastern Brazil,

Agbenin and Tiessen (1995) found a downslope decreasing

total P concentration as in the Lomas. They concluded from

the studied toposequence that in arid environments, the

distribution of P results from complex interactions of

lithology, weathering, colluvial actions and climatic con-

ditions (moisture deficit followed by intense rainfalls).

In the Lomas, the plant cover increases from the bottom

to the top of the relief where heavy fogs (May to October)

enable vegetation growth, limiting erosion processes at the

top with subsequent accumulation of the different forms of

phosphorus generally associated to finest soil particles.

5. Conclusion

The Lomas constitute an original landscape chiefly

characterized by: a) the localization near the Pacific Ocean

and the presence of the cold Humboldt Current; b) the

topography (regular increase of the altitude from around 100

to 1000 m) which acts as a barrier to Ocean influences,

causing fogs, especially between 600 to 1000 m (May to

October) or receiving heavy rainfalls during ENSO events.

With regard to the vegetation, the specific climatic

conditions leads to a strong contrast between long periods

of seed dormancy then short periods of growth, the trigger

mechanism being rainfalls associated to ENSO events.

Considering phosphorus, two periods are particularly

important: a) the beginning of the drought with release of

labile P (plants decaying and microbial cells killed) and its

accumulation in the soil; b) rainfall with wetting of the soil

permitting the growth of vegetation, especially of the

ephemeral burst in a continuous blanket. In this respect

the Lomas characteristics, that is the rainy period following

the long dry period contribute to the overall fertility of the

soil, especially as the labile forms of phosphorus are

concerned the most.

Acknowledgments

The authors thank M.F. Bellan and D. Lacaze for the

field assistance and F. Barthelat, K. Saint-Hilaire and M.

Saurat for help with many chemical analyses. The study

received financial support from European Communities:

Contrat U.E. n- TS3 CT 94 0324 (1995–1998): ‘‘Fog as a

new water resource for the sustainable development of the

ecosystem of the Peruvian and Chilean coastal desert’’.

Project Coordinator: Dr Roberto Semenzato (1995–1997)

and Dr Mario Falciai (1997–1998).

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