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Trophic ecology study contribution Anas Platyrhynchos (linne, 1758) in the Reghaia's Lake National Reserve, Algeria.

ABSTRACT

Studies on the diet of Mallard Duck Anas platyrhynchos(Linne, 1758) was carried out from February 2011 until January 2012 in the fen of Reghaia's lake, sub-humid area located in the North of Algeria. The diet study of the Mallard duck requires prior inventory of trophic environment availabilities. This inventory allowed recording considerable diversity in plant species, Paspalum distichum is the most abundant species. It is followed by Typha angustifolia. The faunistic biodiversity study by Barber's pots in Reghaia's humid area, allowed discerning 975 invertebrates. They spread into 7 classes(Gastropoda, Arachnida, Crustacea, Myriapoda, PodurataandInsecta), 21 orders and 115 species. In terms of richness, insecta are noted with 93 species (83,9%). Catch of species by kick net allowed capture of 1457 individuals. They belong to 8 classes, 14 orders, 23 families, and 23 species. The most represented order is that one of Diptera with 6 species followed by the one of Coleoptera with 5 plant species. The dietary regime study of the Mallard duck at level of Reghaia's lake through their droppings' analysis allowed us inventorying 24 plant species consumed. It is about 8 Poaceae which are quoted certain species frequently ingested: Hordeum murinum and Poa annua, 1 Typhacee Typha latifolia and 1 Cyperacees Scirpus sp, followed by family of Iridaceae represented by Iris pseudacurus, and family of Plantaginaceae by Plantago crasiifolia. Animal preys are essentially composed of 40% of Tabanidaesp.ind (Diptera),20,0% of Chironomides (Diptera), and Monomoriumsp.ind(Hymenoptera). The diet study of the Mallard Duck confirmed the herbivorous character of this species. It possesses an omnivorous dietary regime where plants are generally predominant.

KEYWORDS: Anatidae, Anas platyrhynchos (Linne, 1758), Diet, Reghaia's lake, Algeria.

INTRODUCTION

North of Africa hosts a wide humid area diversity which constitutes wintering sites and of staging of Palaearctic migratory birds[19]. Algeria has a set of wetlands distributed not only on the coastal regions, but also in the highlands and the Sahara [14].

Within this broad package, Algeria which the territory belongs to western Palearctic area, is known by its large diversity, it hosts nearly all habitats of the field and holds a varied species heritage depending to humid areas [2].

Water birds occupy at level of food webs, various positions (herbivorous, zooplanctonivorous, insectivorous, piscivorous) generally located on the top of food chains and their diversity informs us on the various environments functioning where they are settling[21]. Thus, knowledge of this birds' dietary regime is crucial to identify role of this group over the structure and humid areas functioning. Anas platyrhynchosis widely spread through Algerian humid regions. It constitutes an excellent biological model which can be seen as a bio-indicator of structure and hydro-systems functioning [24]. Very few studies on the diet of waterbirds have been carried out in Algeria; In particular, [22] in Chott Ain El-Beida in Ouargla, and [4] in Lake Tonga and the Makhada Marsh, [14] Predators who are waterbirds and their prey at El Kala National Park (Lake Tonga).To better understand these ecosystems functioning, and to carry out properly trophic ecology of Anas platyrhynchos relationship animal-plant were approached, by evaluation in trophic resources availabilities of environments frequented by Anas platyrhynchos and in the second time by study of its dietary based on droppings analysis. This contribution is added to few studies made in Algeria on duck's dietary regime.

MATERIAL AND METHODS

Material:

Presentation of biological model: Anas platyrhynchos (Mallard Duck)

Systematic position:

Mallard Duck (Anas platyrhynchos, Linne, 1758 is the numerous species by populations among Rallidae. It belongs to Aves birds class, to Anseriformes order to Anatidae family [18].

Species description:

This is the biggest duck in France, It is the largest duck of surface, the most common and the most largely spread. Ancestor of domestic duck, male has a dark green head (with purplish colour prior the moult) thin white collar, chest with purplish-brown colour, beak always yellow, blue-purple mirror. Duck (female): greenish beak while the juvenile has a red beak [16].Lenght 50 to 65 cm, weight 750 to1450g. (Fig.01)

[FIGURE 1 OMITTED]

Diet:

This duck of surface is able, to breed, to dabble until 48 cm, but also to move back with its beak the water surface with its feet or in swimming, Hence, it can consume aerial floating and immersed parts of aquatic plants, even underground parts burrowed in the mud, and so grains[12]

Methods:

The adopted method to study Mallard duck's dietary regime is this one of droppings analysis. This analysis way does not be applied in the major cases but only to Phytophagous birds which let droppings constituted of fragments easily identifiable[8]. According to [10], this analysis method offers several advantages. There is no need to use capture of the bird which is often difficult. Hence, this method has no limit in either time or space and moment of droppings collection. Reghaia lake is located between latitudes 36[degrees]45' and 36[degrees]48' North and longitude 03[degrees]19' and 03[degrees]21' East. It is a part of Mitidja's plain, at 30 km East of Algiers. Located in the South of Mediterranean sea and at less than 10 m altitude. Climatological analysis shows that the study region belongs to a bioclimatic sub-humid notably characterised by dry and hot summers and by mild and humid winters. We were able to harvest 200 droppings, at the rate of 16 droppings for each month which is from February 2011 until January 2012 belonging to different individuals. Direct observation is made thanks to a pair of binoculars which is the most reliable means to locate droppings (Fig. 2). Then, droppings are gathered and stored in paper cones, bearing spot and date of the collection.

In the laboratory, these droppings are put in Petri boxes containing alcohol to soften them. They are shelled with pins, and their constituent elements are spread at the bottom of the box. The remains of animal and plants are determined after air-drying.

Grains are easily determined by comparing them to a reference collection of epidermis and epicarp are identified in comparison with references collection of epidermis made thanks to species of known plants. In order to constitute that one, epidermis were removed from plants by detaching them from underlying tissues thanks to a pair of fine claws or by scraping [5,6] .These epidermises, collected from the plant or found in the droppings are put during some minutes into a bleach bath to destroy cellular contents and turn epidermal cells outlines more apparent (Fig. 3).

[FIGURE 2 OMITTED]

[FIGURE 3 OMITTED]

Availabilities evaluation of study environment trophic resources:

Vegetation sampling by vegetal transect method:

A vegetal transect is a plant structure description and its physiognomy, according to the representation being orthogonal of in profile. It consists to delimit a surface of 500 m2, which is 50 m length x 10 m width in which are identified all present plants species. A herbarium has also been carried out from floristic inventory around the Reghaia's lake. This latter would then serve for conception of a reference collection of epidermis

Invertebrate estimation by Barber pots method:

Use of buried traps or Barber pots allows catching various species of arthropods which are moving quickly on ground surface, and so a great number of flying insects.[11]. Pots are buried just above the ground surface. Each trap is full of water at 1/3 of its height. We add as wetting substance a bit of soap to prevent trapped animals to escape.

Aquatic invertebrates estimation by a kick net method:

This instrument allows catching aquatic invertebrates. It is constituted by a frame and a net made of a canvas sufficiently permeable to allow trapping aquatic insects, because water exerts a high resistance

Results:

Diagnostic results:

The Anas platyrhynchos dietary regime, allowed us inventorying 24 vegetal species consumed. Class of monocotyledons is represented by 3 botanical families. It is about 8 Poaceae which we quote some species frequently ingested: Hordeum murinum and Poa annua, 2 Cyperacees Scirpus sp. and Scirpus maritimus et d'une Typhacee Typha latifolia. Class of dicotyledons gathers 9 families. We quote family of Convolvulaceae represented by Calystegia sepium, followed by family of Iridaceae represented Iris Pseudacurus, and family of Plantaginaceae by Plantago crasiifolia. Table 1.

The sampling quality calculated in our study station, is equal to 0,003, with 11 species contacted once, it is about Apium nodiflorum, Plantago major, Lolium multiflorum, Avena sterilis, Graminees inditerminees, Plantago crasiifolia, Polygonum lapathifolium and Rumex conglumeratus. The most important total richness is noted on February with an number of 24 vegetal species ingested. Anas platyrhynchos 'diet is essentially constituted of plants, is dominated by grasses with 93%.Among these grasses, 3 species are more palatable Hordeum murinum (35,65%) and Paspalum distichum (25, 02%) on February. The highest monthly presence percentages of species ingested by Mallard duck are calculated for almost all the Grasses. We noted for Hordeum murinum and Paspalum distichum, maximal frequencies 93,33 % for Poa annua.Furthermore, other species other than Grassescan be found in important rates. We quote Poaceae Paspalum distichun which represents nearly all menu totality of our bird species Anas platyrhynchos during this period. The Mallard duck's dietary regime confirmed herbivorous character of this species. It possesses an omnivorous diet in which vegetal are generally predominant.

The faunistic biodiversity study of the humid zone of Reghaia, is based on use of trap pots, methods that allowed discerning 965 invertebrates inventoried. They are spread between 3 classes (Gastropoda, Arachnida, Crustacea, Myriapoda, Podurata and Insecta), 8 ordres and 117 species. In terms of richness, insecta are noted with 95 species (82,9%) in Barber pots. Within insecta, Hymeoptera are best represented in Barber pots (731 individuals, 77,5 %). Table2.

The capture of species by kick net allowed catching of 1467 individuals. They belong to 8 classes, 14 orders, 23 families, and 24 species. The most presented order is of Diptera with 5 species followed by Coleopterans with 4. The total richness value is equal to 24 species, while average richness is of 10,75. Captured species by kick net belong to 7 classes with this of dominant Branchiopod (RA%=58,3%) followed by this of Ostracods 25,4% (Figure 4) .

[FIGURE 4 OMITTED]

The relative abundances of other classes are low (0,2 %<AR%<7,2%.). Diversity value of Shannon-Weaver is equal to 2.0. This expresses that the study station is diversified. While maximal value is equal to 4,6 (Figure 5). Equitability value tends towards 0, which means there is an imbalance between populations of different species sampled. (Figure 6)

[FIGURE 5 OMITTED]

[FIGURE 6 OMITTED]

Furthermore, centesimal frequencies of different classes inventoried thanks to Barber's pots are presented in figure7.
Fig. 7: centesimal frequencies of trapped species in Barber's pots
according to the Orders.

Insecta,     88.40%
Gastropoda,  0.73%
Arachnida,   5.59%
Crustacea,   4.46%
Myriapoda,   0.62%
Podurata,    0.20%


Index of species selection ingested by Anas platyrhynchos:

Index of Ivlev allow measuring selection of various preys captured by kick net, and ingested by Anas platyrhynchos, we could deduce the selectivity action, the results based on selection index are maintained in the table 2.

22 species are not consumed by Anas platyrhynchos:

(Li = - 1), such as Phyla sp.and Albea can did issima and Cypria sp. These species are present in the study environment but they are not consumed by Anas platyrhynchos. They are not sought by the predatory. By contrast, the positives values of Ivlev's index are found in Chironomidae sp.ind(Li = 0,84), this species is much more frequent in the duck's diet than on the ground.

[right floor]Li=-0,484 for Daphnia pulex, it is relatively sought by Anas platyrhynchos compared to 22 species which their Li = -1.

Principal components analysis results in (PCA) for the 11 species ingested. To easily view influence of species ingested by Anas platyrhynchos and to have an idea on selectivity during the food phases; analyses in main components have been made. In this analysis, we retained 11 vegetal species. The PCA was carried out on centred and reduced data compared at their average and the standard deviation. Use of standardized data, allows dispensing of measures unites which are heterogeneous in our case. The correlation matrix let appear distribution of plants species on two factors (F1 and F2).

Formation of axis F1 is notably due to the participation of ingested-species by Anas platyrhynchos with an equal rate of 71.63% (Fig.8)

Specifical ingested-species by Mallard duck are: Grainssp1. indAsteraceaesp.ind, Lavatera sp.ind, Daphnia pulex, Tabanidae sp.ind. - and Monomorium sp.

[FIGURE 8 OMITTED]

Discussion:

In the present study, buried pots technique application allowed harvesting a great invertebrate's number belonging to 3 classes, which are Gastropods, Arachnids, Crustaceans, Podurata, Myriapoda and Insecta. Results obtained at Reghaia on species number, families and orders were near to those mentioned by [3] and by [9]. By contrast, the results of the present work seem to be different from those made by [15] in the North of Benin in the whole of cultural associations. These authors record presence of 133 species spread between 64 families and 9 orders. However, this author mentions 77 families, which is the higher number than this quoted in Reghaia [1] in five stations of Mont Babor's natural reserve trapped thanks to Barber's pots, 209 species spread between 72 Coleopteran's families. Number of species is upper than this obtained by the present study (115 species) which are more than 40 species. In an anthropized environment such as plain employed by intensive grain cropping in south of Deux-Sevres France [7] record 22 species spread between 9 families and 4 orders. The results found by these authors remain low compared with those of the present study. The dietary regime of Anas platyrhynchos is essentially constituted by plants, and is dominated by grasses.

As for April and May months, only one grass has been ingested. Furthermore, some species less frequent can be found such as Iris pseudacurus (3,[degrees]15 %) and Plantago crasiifolia (6,17%). Concerning duck's feeding during April and May, we can say that is globally different. It is digitally very represented by grasses Paspalum distichum with 92,80 % (April) and 97 % (May). By contrast, both remaining species present very lower centesimal frequencies ; Scirpus sp.ind with.0,73% (April) and 2,70 % (May).; and Scirpus maritimus with 2,47 % (April) and 0,30 % (May). However, other species other than Grasses can be found in important percentages. We quote in February a Convolvulaceae Calystegia sepium (81%), and a Plantaginaceae Plantago crasiifolia (80%). As for April and May, the high presence rate which represents almost totality is noted for Poaceae Paspalum distichun which represent nearly all diet of our bird species during this period. [8], show that in herbivorous, the most generalist species is the Anas platyrhynchos having a very varied dietary regime according to localities, among surface ducks, the Mallard can be granivorous where we have noticed also in our study and as a consequence confirm our results. [23] noted that the Anas platyrhynchos consumes 95% of plants preys essentially grains and 5% of animal preys. These results are very close of those we have obtained in our study.

Conclusion:

Water birds are important elements in humid areas because they have heritage and scientific value and because they can constitute a feeding resource for some of them, and also they may inform us about state and functioning of aquatic ecosystem. If water birds disappear from a humidzone, this may signify in some cases the vegetable or animal resources become scarce including human population [23].Analysis of Anas platyrhynchos droppings showed that this duck consumes 81,8% of vegetable preys and 8,2% of animal preys. Animal preys constitute essentially 25% of Tabanidae sp.ind (Diptera) and19% Chironomidae (Diptera), Monomorium sp.ind(Hymenoptera) and Daphnia pulex (Cladocera).The major plants preys and the most dominant are grains. Grains (sp.ind) non identified constitutes the majority of grains with RA%=79,3% and Ruppia maritima (Ruppiaceae) with1,8%, and two other grains which are Asteraceae sp.ind and Lavatera sp.ind. [23])in Camargue (South of France), show that Anas platyrhynchos feeds of vegetable parts (74%), (18% ) of grains and (8%) of algae. The same authors found that Potamogeton sp.ind, was present. In spite of environmental conditions (temperature, air humidity, water quality and food availability) totally different at level of the two environments (lakes): Results of this study are similar to those of [23] concerning the vegetative fraction, with presence of Potamogetonaceae.

These results are very close to those we have obtained from our study. According to[17] availability and accessibility of food resources are among of the main factors determining aquatic birds' distribution. Generally, the Sahel and Algerian Littoral contain a very high flora and fauna richness, and consequently, offer important food resources in diversity and in quantity, which allow so, settling of birds belonging to different trophic categories [20].[8], Shows that in the herbivores the most generalist species is the mallard which has a very varied diet depending on the localities, among the ducks of surface, the Mallard can be granivore as on a also to see it in our study and of This confirms our results. Comparatively to results found by authors quoted above, it is fair to say that Anas platyrhynchos feeds of vegetal grains, which it is its granivorous dietary regime.

It should be noted that this study, the first of its kind devoted to aquatic avifauna, confronted us with the problem of the lack of data in order to be able to compare and situate the results that we obtained.

This contribution is in addition to the very few studies carried out in Algeria on the diet of ducks. But in order to enrich the studies on this type of topic in this region, it is important to encourage research by establishing research axes dealing with diets of avian species especially aquatic. And studies on the conservation and restoration of wetlands so that they can harbor the maximum number of waterbirds.

REFERENCES

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[2] Bensaci, E., M.Saheb, Y. Nouidjem, A. Bouzegag and M. Houhamdi, 2013-Biodiversite de l'avifaune aquatique des zones humides sahariennes: cas de la depression d'Oued Righ (Algerie). Physio-Geo. V7.

[3] Boukeroui, N., S. Doumandji and N. Chebouti- Meziou, 2007. L'entomofaune du pistachier fruitier (Pistacia vera Linne) dans la region de Blida. Journees internationales Zool. agri. for., 8 - 10 avril 2007, Dep. Zool. agro. for., Inst. nati. agro., El Harrach, p: 203.

[4] BOURIACH, H.,2010--Regime alimentaire des canards et des foulques hivernant saulac Tonga et le marais de la Mkheda.Memo.Master.Univ.08 Mai 1945.Guelma. p:89.

[5] But et, A., 1985 -Methode d'etude du egime alimentaire d'un rongeur polyphage (Apodemus sylvaticus L., 1758) parl' analyse microscopique des feces. Mammalia, 49(4):450-483.

[6] Butet, A.,1987- L'analyse microscopique des feces: une technique non perturbante d'etude des regimes alimentaires des mammiferes phytophages Arvicola, 4(1): 33-38.

[7] Clere, E. and V. Bretagnolle, 2001 - Disponibilite alimentaire pour les oiseaux en milieu agricole: Biomasse et diversite des arthropodes captures par la methode des pots-pieges. Rev. Ecol. (Terre Vie), 56: 275-297.

[8] Compredon, S., P. Compredon, J. Yves Pirot and A. Tamisier, 1982 - Manuel d'analyse des contenus stomacaux de canards et de foulques. Office National de la chasse, Paris., p:87.

[9] Dehina, b. N., S. Daoudi-Hacine and S. Doumandji, 2007 - Arthropodofaune et place des Formicidae dans un milieu a vocation agricole. Journees internationales Zool. agri. et for., 8 - 10 avril 2007, Dep. Zool. agro. for., Inst. nati. agro., El Harrach, p:201.

[10] Ebbing, B., K. Canters and R. Drent,1975- Forming routines and estimated daily food intake in Barnacle geese wintering in the northern Netherlands. Wildfowl, 26:5-19.

[11] Faurie, C., C.Farra and P.Medori,1978-Ecologie.Ed.J.B.Bailliere, Paris, p: 147.

[12] Frochot, B.,2003. Partez a la rencontre de la biodiversite: Les oiseaux d'eau nicheurs du bassin Artois Picardie. Ed. Agence de l'eau, France, p:17.

[13] Jacobsen, O.W., 1996-Habitat Selection by Breeding Eurasian Wigeon (Anas Penelope L.) in Western Norway. Gibier Faune Sauvage, 13(2): 667-679.

[14] HAIAHEM D et GHAZI L, 2010--La distribution Spatio-temporalle des proies/predateurs.Memo. Master. Univ. 08 Mai. 1945. Guelma, p:58.

[15] Hautier, L., S. Patiny, A. Thomas- Odjo and C.Gaspard, 2003- Evaluation de la biodiversite de l'entomofaune circulante au seind' associations culturales au Nord Benin. Notes faunistiques de Gembloux, (52): 39-51.

[16] Heinzel, H., R. Fitter and J. Parslow, 2004. Les oiseaux d'Europe, d'Afrique du Nord et du Moyen-Orient.Ed. Delachaux et Niestle, Paris, p:319.

[17] Jacobsen, O.W., 1996.Habitat Selection by Breeding Eurasian Wigeon (Anas Penelope L.) in Western Norway. Gibier Faune Sauvage, 13(2): 667-679.

[18] Killian, M., S. Lars, Z.Dan and J. Peter, 2009.Le guide ornitho. Ed. Delachaux et Niestle, Paris, p:400.

[19] Meddour, S., 2013. Etude du regime alimentaire de la Foulque macroule et de quelques especes d'Anatidae au niveau de Sebkhet El-Maleh (El-Menea W.Ghardaia), p:87.

[20] Milla, A., 2008. Comportement journalier du Bulbul des jardins (Pycnonotus barbatus) dans deux milieux suburbains du Sahel algerois (Algerie). Aves, 42(1/2): 156-162.

[21] Samraoui, B., and F. Samraoui, 2008- An ornithological survey of Algerian wetlands: Important Bird Areas, Ramsar sites and threatened species. Wildfowl, 58: 71-96.

[22] TADJINE, B., 2010--Etude du regime alimentaire de l'Echasse blanche Himantopus himantopus (Linaeus, 1758) dans le Chott Ain El-Beida [laquo] Ouargla [raquo]. Memo. Ing.Agro. Univ. Kasdi Merbah. Ouargla, p:98.

[23] Tamisier, A. and O.Dehoter,1999.Camargue, canards et foulques. Fonctionnement d'un prestigieux quartier d'hiver. Centre Ornithologique du Gard, CNRS, Montpellier, p:369.

[24] Yahia cherif Sadaoui, S., 2015.Etude ecologique, dynamique et biosystematique de l'avifaune du lac d'el Golea et du marais de Reghaia et comparaison faunistique entre les deux zones. These Doctorat, Inst. nati. agro., El Harrach, p: 213.

(1) Samia Sadaoui-Yahia Cherif, (2) Ahlem Guerzou and (1) Abdeslem Arab

(1) U.S.T.H.B, Faculty of biological sciences, El Alia, Algiers, Algeria.

(2) Beekeeping Laboratory Department of Animal Science ENSA, Algiers, Algeria.

Address For Correspondence:

Samia Sadaoui-Yahia Cherif, U.S.T.H.B, Faculty of biological sciences, El Alia, Algiers, Algeria.

This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/

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Received 12 January 2016; Accepted 10 March 2017; Available online 26 March 2017
Table 1: Inventory, numbers and relative abundances of preys-species
found in Anas platyrhynchos droppings.

Classes          FAMILIES        SPECIES

Monocotyledones  Poaceae         Phragmites australis
                                 Hordeum murinum
                                 Lolium multiflorum
                                 Paspalum distichum
                                 Avena sterilis
                                 Bromus hordeaceus
                                 Poa annua
                                 Graminees indeterminees
                 Typhaceae       Typha anguistifolia
                 Cyperaceae      Scirpus maritimus
Dicotyledones    Convolvulaceae  Calystegia sepium
                 Plantaginaceae  Plantago Lanceolata
                 Iridaceae       Iris pseudacurus
                 Fabaceae        Trifolium repens
                 Polygonaceae    Polygonum lapathifolium
                                 Rumex conglumeratus
                 Apiaceae        Apium nodiflorum
                 Asteraceae      Sonchus teneremu
                 Chenopodiaceae  Chenopodium sp.
                 Solanaceae      Solanum nigrum
                                 Rubia peregina

Table 2: Inventory, numbers and relative abundances of preys-species
found in Anas platyrhynchos droppings.

Classes       Ordres          FAMILIES       SPECIES               Ni

Arachnida     Mesostigmata    Gamasidae      Gamasidae sp.ind      75
              Sarcoptiformes  Oribatidae     Oribatidae sp.ind     41
Branchiopoda  Cladocera       Daphniidae     Daphnia pulex         562
              Anostraca       Artemiidae     Artemia sp.           33
Ostracoda     Podocopida      Cyprididae     Cypria sp.            3
                              Hydrophilidae  Hydrophilidae sp.ind  5
                              Chironomidae   Chironomidae sp.      25
                              Limoniidae     Limoniidae sp.ind     3
              Hemiptera       Corixidae      Sigara sp.ind         17
                              Notonectidae   Notonectidae sp.ind   1
                              Gerridae       Gerridaesp.ind        2
              Trichoptera     2 Familleind   Trichoptera sp.ind    2
              Basommatophora  Physidae       Physa sp.             53
3 classes
Classes       AR%
Arachnida     4,43
              2,79
Branchiopoda  52,03
              2,25
Ostracoda     25,43
              0,34
              1,70
              0,20
              0,95
              0,07
              0,14
              0,14
              2,93
3 classes     100

Ni: population, RA% relative abundance.

Table 2: Selection indexes of ingested-species by Anas platyrhynchos
during the study period (2011-2012)

SPECIES              RA%DA  RA%RA  Li

Clitellatasp.ind     0,41   0,00   -1
Gamasidae sp.ind     4,43   0,00   -1
Oribatidae sp.ind    2,69   0,00   -1
Daphnia pulex        45,03  20,00  -0,484
Artemia sp.           2,25   0,00   -1
Cypria sp.            25,43  0,00   -1
Coleoptera sp.ind    0,55   0,00   -1
Hydroporus sp.ind    0,55   0,00   -1
Tabanidae sp.ind     0,00   40,00  1
Empididae sp.ind     0,07   0,00   -1
Ephydridae sp.ind    0,27   0,00   -1
Psychodidae sp.ind   0,07   0,00   -1
Limoniidae sp.ind    0,20   0,00   -1
Chironomidae sp.ind  1,80   21,00  0,832
Monomorium sp.       0,00   22,00  1
Odonatoptera sp.ind  0,07   0,00   -1
Albea candidissima   0,07   0,00   -1
Physa sp.            2,72   0,00   -1
Nematoda sp.ind      0,20   0,00   -1

Li = selection index
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Author:Cherif, Samia Sadaoui-Yahia; Guerzou, Ahlem; Arab, Abdeslem
Publication:Advances in Environmental Biology
Article Type:Report
Geographic Code:6ALGE
Date:Mar 1, 2017
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