BOOK REVIEWS

Book Reviewed in this article: Anhuf, Dieter. 1997. Satellitenbildgestützte Vegetationklassifikation der Côte d'Ivoire. Mannheimer Geographische Arbeiten 45. ix + 190 pp. ISBN Price: Anhuf, Dieter (ed.). Forschungen im französischsprachigen Ausland. Mannheimer Geographische Arbeiten 43. 179 pp. ISBN Price:     

The Spread of African Cassava Mosaic Virus into and within Cassava Fields

Only a small proportion of Bemisia tabaci collected in totally infected cassava fields at a site in Côte d'lvoire transmitted African cassava mosaic virus (ACMV) to test plants. Nevertheless, the monthly increase in disease incidence in an experimental planting was directly related to numbers of adult whiteflies counted on plants 6 weeks earlier. In plots at different spacings, the greatest incidence of ACMV expressed as a percentage of the total stand occurred at the lowest plant density. Much speread into the spacing trial and into two other experimental plantings occurred from outside sources and followed downwind gradients. By contrast, spread from ACMV-infected sources within plantings was limited. It occurred in all directions but over distances of only a few metres. These contrasting patterns of spread are attributed to the differentbehavior of B. tabaci above and within the crop canopy. It is concluded that contamination of cassava fields in the coastal forest area of Côte d'Ivoire is due mainly to rapid spread from outside sources which leads to internal foci that contribute to some further, although limited, spread. These findings are discussed in relation to possible control strategies based on the release of healthy cuttings, dense planting and subsequent roguing. Such measures are unlikely to be effectve in the coastal forest region of Côte d'Ivoire and adjacent countriesunless varieties are grown with greater resistance to infection than those currently used.     

Carrion fly‐derived DNA as a tool for comprehensive and cost‐effective assessment of mammalian biodiversity

Large‐scale monitoring schemes are essential in assessing global mammalian biodiversity, and in this framework, leeches have recently been promoted as an indirect source of DNA from terrestrial mammal species. Carrion feeding flies are ubiquitous and can be expected to feed on many vertebrate carcasses. Hence, we tested whether fly‐derived DNA analysis may also serve as a novel tool for mammalian diversity surveys. We screened DNA extracted from 201 carrion flies collected in tropical habitats of Côte d'Ivoire and Madagascar for mammal DNA using multiple PCR systems and retrieved DNA sequences from a diverse set of species (22 in Côte d'Ivoire, four in Madagascar) exploiting distinct forest strata and displaying a broad range of body sizes. Deep sequencing of amplicons generated from pools of flies performed equally well as individual sequencing approaches. We conclude that the analysis of fly‐derived DNA can be implemented in a very rapid and cost‐effective manner and will give a relatively unbiased picture of local mammal diversity. Carrion flies therefore represent an extraordinary and thus far unexploited resource of mammal DNA, which will probably prove useful for future inventories of wild mammal communities.     

Composition and Intraspecific Chemical Variability of Leaf Essential Oil of Laggera pterodonta from Côte d'Ivoire

The chemical composition of 44 leaf oil samples of Laggera pterodonta (DC.) Sch.Bip. ex Oliv. (Asteraceae) from Côte d'Ivoire was investigated, using combination of chromatographic (GC‐FID) and spectroscopic (GC/MS, ¹³C‐NMR) techniques. Two oil samples chosen according to their chromatographic profiles were submitted to column chromatography and all fractions of CC were analyzed by GC‐FID, GC/MS and ¹³C‐NMR. In total, 83 components accounting for 96.5 to 99.4 % of the whole chemical composition were identified. Significant variations were observed within terpene classes: monoterpene hydrocarbons (0.4–22.7 %), oxygenated monoterpenes (32.9–54.9 %), sesquiterpene hydrocarbons (18.6–38.3 %) and oxygenated sesquiterpenes (3.5–38.4 %). Thus, the 44 compositions were subjected to hierarchical cluster analysis (HCA) and principal component analysis (PCA). Two groups were differentiated according to their composition. All the samples contained 2,5‐dimethoxy‐p‐cymene, α‐humulene and (E)‐β‐caryophyllene among the main components. Other components were present at appreciable contents and allowed differentiation of two groups: sabinene and germacrene D for Group I; 10‐epi‐γ‐eudesmol and eudesm‐7(11)‐en‐4α‐ol for Group II. All the samples collected in Eastern Côte d'Ivoire constituted Group I, while samples collected in the Central area of the country constituted Group II.     

Sleep-Wake Cycle of Adolescents in Côte d'Ivoire: Influence of Age,Gender, Religion and Occupation

The human sleep-wake cycle is characterized by significant individual differences. Those differences in the sleep-wake cycle are partially heritable but are also influenced by environmental factors like the light/dark cycle or social habits. In this study we analyse for the first time the sleep-wake rhythm of adolescent pupils and working adolescents in a less industrialised country in West Africa near the equator. The aim of this study was to explore the sleep wake cycle in this geographical region, using Côte d'Ivoire as an example. Data collection took place between 2nd of March and 10th of June 2009. 588 adolescents (338 girls, 250 boys) between 10 and 15 years (mean?±?SD: 12.72?±?1.63) participated in this study. We collected data on the religion of the participants (Christian (N?=?159), Muslim (N?=?352), other/no religion (N?=?77)) and their occupation. Participants were either pupils attending school (N?=?336) or adolescents that were already working (N?=?252) and not attending school. The interviewer filled in the questionnaire. We found significant effects of age (p?<?0.001), gender (p?<?0.001), occupation (p?=?0.002), religion (p?<?0.001) and region (p?<?0.001). The midpoint of sleep was on average 1:26 (SD: 00:30) on weekdays and 1:37 (SD: 00:42) on weekend days. There are significant differences between weekdays and weekend days, but these were only small. Sleep duration suggests that adolescents in Côte d'Ivoire may gain sufficient sleep during week and weekend days, and thus, may live more in accordance with their own biological clock than adolescents in the northern hemisphere. In contrast, the data can be interpreted that adolescents live in a permanent ‘jetlag’. Factors may be the more continuous light/dark cycle in the tropics, low amount of ambient light and less electricity.     

A contribution to the study of the avifauna of the Bossematie Forest (Abengorou/Côte d'Ivoire). The future of Bossematie Forest: current status

Yaokokore Beibro, K.H. & Ellenberg, H. 2000. A contribution to the study of the avifauna of the Bossematie Forest (Abengorou/Côte D'Ivoire). The future of Bossematie Forest: current status. Ostrich 71 (1 & 2): 292–294.

The Bossematie forest, eastern Cdte d'Ivoire (3°35'-3°20' longitude west and 6°35'6°20' latitude north), has been heavily exploited in the past and is now being rehabilitated by the SODEFOR (Societe de Developpement des Forêts) and the GTZ (German Technical Co-operation). To estimate the potential for the rehabilitation, the bird fauna was studied during a four year period including the field work of three observers of about 24 person-months. Until now we recorded in the forest and the surroundings 337 species belonging to 203 genera and 58 families. 251 species were present within the forest borders with 133 only observed there and not outside. Five species are considered as near-threatened and four species as vulnerable. To study the ecology of forest species in more detail, an intensive analysis of the communities of different forest stages and treatments was carried out by the first author.     

Viral infection cycles in pike (Esox lucius L.)

Pike fry weighing 0.2 g were infected with five pathogenic viruses via the water and then fed to one-year-old, 60 g pike. A transer of the viruses from the prey to the predator was demonstrated. The VHS virus produced typical hermorrhages in the muscle of the second nost. Zusammenfassung Zyklische Virusinfektion beim Hecht (Esox lucius L.) Auf dem Wasserweg mit fünf fischpathogenen Viren infizierte Hechtbrut (0,2 g) diente einjährigen Hechten (60 g) als Nahrungsquelle und gewährleistete hierdurch den Virustransfer. Das VHS-Virus induzierte im 2. Wirt typische Hämorrhagien in der Muskulatur. Résumé Cycles d'infection viraie chez le brocket (Esox lucius L.) Des embryons du brochet (0,2 g) inficés par l'eau servaient comme nourriture pour des brochets agés un an (60 g). Par cela le transfer du virus était verifié. Le virus VHS causait dans l'hôte seconde des hemorrhages typiques dans les muscles.     

Inventory and abundance of mealybug species in immature and mature cocoa farms in Côte d'Ivoire

From 2013 to 2018, surveys were conducted in counties not previously surveyed in order to determine species of mealybugs present in the cocoa orchard in Côte d'Ivoire as well as their abundance according to the age of cocoa trees. Immature and mature cocoa trees were inspected to hand‐height in 5 and 29 counties infected with Cacao swollen shoot virus (CSSV). In each cocoa farm, mealybugs were searched for on fruits, leaves, flowers, twigs and trunks. Mealybug species were identified, and colonies were counted. Five mealybug species were identified on immature cocoa trees: Ferrisia virgata, Formicococcus njalensis, Planococcus citri, Planococcus kenyae and Pseudococcus longispinus. In addition to these species, four species, Dysmicoccus brevipes, Maconellicoccus hirsutus, Phenacoccus hargreavesi and Pseudococcus jackbeardsleyi were identified on mature cocoa trees. On immature cocoa trees, Fo. Njalensis, Pl. citri and Ps. longispinus comprised were, respectively, 35%, 33% and 19% of colonies, respectively. On mature cocoa trees, Fo. Njalensis and Pl. citri comprised 63.2% and 21.0%, and others species 15.8%. Nevertheless, the abundance of mealybug species varied according to the age of cocoa trees. The preferred organs of mealybugs were pods (74.1%) followed by twigs (13.4%) and flowers (7.4%). Previously, the mealybug Paracoccus burnerae (Brain) was found on Theobroma cacao, which is the first record for this species in Côte d'Ivoire and on this host‐plant.     

Reviews

Book Reviewed in this article: Neuweiler, G. 1993: Biologie der Fledermäuse. Georg Thieme Verlag, Stuttgart, New York. Vitt, L. J. & Pianka, E. R. (eds) 1994: Lizard ecology. Historical and experimental perspectives. Zeigler, H. P. & Bischof, H.-J. (eds) 1993: Vision, brain, and behavior in birds. MIT Press, Cambridge. Springer, S. P. & Deutsch, G. (Hrsg.) 1995: Linkes-Rechtes Gehirn. Spektrum Akademischer Verlag, Heidelberg, Berlin, Oxford. Chinery, M. 1993: Pareys Buch der Insekten—Ein Feldführer der europäischen Insekten. 2. Aufl., übersetzt und bearbeitet von Dr. Irmgard Jung und Dr. Dieter Jung.     

Enjeux,défis,opportunités et stratégie durable d’implantation de l’imagerie hybride TEMP/TDM dans un pays à ressources médicales limitées,la Côte d’Ivoire

From HO Anger's analogic gamma camera to digital camera, developed countries are at the time of hybrid cameras SPECT/CT and PET/CT. Sub-Saharan black Africa in the image of Côte d’Ivoire, a country with limited medical resources shows an important delay in the evolution of the health system in general and particularly in medical imaging equipment. The purpose of this paper was to approach the issues, challenges and sustainable strategy for the implementation of hybrid imaging SPECT/CT in a developing country where the rate of morbidity and mortality remains high due to infectious but also cancer diseases because of the inadequacy of the health technical platform. To address these challenges, Côte d’Ivoire like many countries in sub-Saharan Africa with limited medical resources must design, test and develop clinical strategies adapted to developing countries. Health authorities of this country must develop a policy for sustainable financing of medical imaging, including the training of the adequate health personnel according to a model of corporate leadership. In this perspective, Côte d’Ivoire must have a SPECT/CT instead of a simple gamma camera. This would allow to optimize its diagnostic health system in oncology, bone and joint disease and in many other medical disciplines. And especially since the SPECT/CT is a high-performance device that has largely demonstrated its diagnostic efficiency and that can be used as SPECT alone or as isolated CT. In addition, this country should take over digital imaging in the context of cooperation with some countries of Africa and Europe ahead in the field of modern medical imaging, seeking assistance from international organizations (IAEA, RAD-AID, WHO,…). Finally this country should implement methods of assessment, types of performance indicators to guide planning for future projects of its system.     

Mosquito (Diptera: Culicidae) Larval Ecology in Rubber Plantations and Rural Villages in Dabou (Côte d'Ivoire)

In Côte d'Ivoire, rubber cultivation has more than doubled since 2010. These mass agricultural areas require a large workforce with little information on how this environment might impact risk of mosquito-borne diseases. The objective of this study was to assess the larval ecology of mosquitoes in rubber areas of Dabou, Côte d'Ivoire. From January to June 2017, an entomological survey was conducted of mature (MP) and immature (IP) rubber plantations, as well as in villages surrounded by rubber plantations (SV) and remote from rubber plantations (RV). The number and type of potential and positive breeding sites were recorded, and mosquito larval densities and diversity were estimated. Seven genera divided into 31 species including major vector such as Anopheles gambiae s.l. and Aedes aegypti were identified. A total of 1,660 waterbodies were identified with a larvae positivity rate of 63.1%. A majority of waterbodies were identified in SV (N?=?875, 53.4% positivity rate), followed by MP (N?=?422, 81.8% positivity rate), IP (N?=?194, 72.2% positivity rate) and least in RV (N?=?169, 57.4% positivity rate). The most important breeding sites for disease vectors were leaf axils in IP (N?=?108, 77.1%), latex collection cups in MP (N?=?332, 96.2%) and the containers abandoned in the SV (N?=?242, 51.8%) as well as in the RV (N?=?59, 60.8%). All these results allow us to affirm that the cultivation of rubber trees has an impact on the larval ecology by increasing the number of available sites and favoring a high larval density and diversity.

     

New Books

Book reviewed in this article: Clemmons , J. R. & Buchholz , R.1997: Behavioral Approaches to Conservation in the Wild. Reagan , D. P. & Waide , R. B. (eds) 1996: The Food Web of a Tropical Rain Forest. Städler , E., Rowell-Rahier , M. & Baur, R . (eds.) 1996: Insect-Plant-Relationships. Reprinted from Entomologia Experimentalis et Applicata 80 (1) 1996, with additional indices, as Series Entomologica, Vol. 53 . Seeley , T. D. 1997: Honigbienen. Im Mikrokosmos des Bienenstocks. (The Wisdom of the Hive, Harvard UP 1995, übersetzt von Ute Döring). Rowe , N. 1996: The Pictorial Guide to the Living Primates. Kuper , A. 1994: The Chosen Primate. Human Nature and Cultural Diversity. Goodwin , B. 1994: Der Leopard, der seine Flecken verliert. Evolution und Komplexität. (How the leopard changed its spots, 1994, aus dem Engl. übers.)     

A simple method for calculating mosquito mortality rates, correcting for seasonal variations in recruitment

Abstract A simple age‐structured exponential growth model is presented for the analysis of the population dynamics of mosquitoes (Diptera: Culicidae). In this model, the proportion of parous mosquitoes R depends on the birth rate β, and the length of the first gonotrophic cycle g, but not on the mortality rate. If the age structure is fairly constant, R= exp(– βg). Extensions of the model correcting for feeding patterns are given. A simple method is applied to an example of Anopheles gambiae Giles biting density and parity ratio in Côte d'Ivoire (fortnightly sampled longitudinal data set), for calculation of the seasonally fluctuating mortality rate, correcting for effects of recruitment. The seasonal variations in birth rate and mortality rate are discussed in relation to variations in density and rainfall.     

Field application of the polymerase chain reaction (PCR) to the detection and characterization of trypanosomes in Glossina longipalpis (Diptera: Glossinidae) in Côte d'Ivoire

The Polymerase Chain Reaction (PCR) technique was used for the identification of natural trypanosome infections in Glossina longipalpis (Diptera: Glossinidae) in Côte d'Ivoire. A total number of 139 flies were examined microscopically for the presence of trypanosomes. Out of them 50 were detected positive and were subsequently prepared for the PCR using primers specific for Trypanosoma (Nannomonas) congolense of Savannah, Riverine-Forest, Kilifi, and Tsavo types, T. (N.) simiae, T. (Duttonella) vivax and Trypanozoon. Almost 90% of the infections detected by the PCR were attributed to Nannomonas, especially T. congolense Savannah and Riverine-Forest types, with many infections in which both of these two types were present T. simiae and T. vivax were also detected in some flies. The sequence specificity of the PCR products was confirmed by hybridization with parasite-type specific DNA probes. Differences between parasitological and PCR results are discussed.     

CARACTÉRISTIQUES DE LA REPRODUCTION DE MACHAERIDIA BILINEATA DANS UNE SAVANE DE CÔTE D'IVOIRE

A partir de dissections systématiques de femelles capturées sur le terrain, une étude des caractéristiques de la reproduction de Machaeridia bilineata Stål a été réalisée dans les savanes de Lamto (Côte d'Ivoire), complétée par quelques données en provenance de Ouango-Fitini. Cet acridien univoltin, une des espèces dominantes de Lamto, passe la saison sèche au stade d'imago immature. Le dépôt du vitellus commence dans les ovocytes vers la mi-février, soit près de 2 mois après les mues. Au cours de sa vie, une femelle ne pond en moyenne qu'une fois et demi à deux fois, mais avec un taux de réussite de 95%. Chaque femelle produit alors de 15 à 20 ?ufs. Une des caractéristiques de cette espèce est la rétention des ovocytes dans les calices avant la ponte. A Ouango-Fitini, les phénomènes sont décalés de 5 à 6 semaines par rapport à Lamto. Il n'y a pas de lien entre le début de la maturation sexuelle et le passage des feux. Pour la période d'étude, il existe une relation avec l'arrivée des premières pluies, mais les limites de ce synchronisme restent à préciser.     

Nouvelle stratégie dans le diagnostic,la prévention et le suivi de l’ostéonécrose drépanocytaire en Côte d’Ivoire à partir de la scintigraphie osseuse

Osteonecrosis is the most frequent complications of sickle-cell disease (SCD) whose prevalence in Côte d’Ivoire is 21%. The main of this study was to compare scintigraphy, clinical and radiological observations to assess earlier diagnosis in SCD osteonecrosis. It was a prospective study about 45 SCD patients who presented coxopathy and had radio-labelled diphosphonates bone scintigraphy. The results revealed 49% of lesions whose 48% appeared wiyh homogeneous hyperfixation, 11% homogeneous hypofixation, 5% of hypofixation contourned by hyperfixation. Eighty-one percent of lesions concerned femoral head, 6% femoral condyle and 3% humoral head. Fifty percent of osteonecrosis was not visible in radiology and corresponded to the earlier stade. These invisible radiology aspects were observed in 100% hips without lameness, and in 43% permanent lameness. Scintigraphy (sensitive in 100%) isolated 38% more than conventional radiography. In main to improve SCD osteonecrosis prognostic in Côte d’Ivoire, this preliminary study outline that scintigraphy is fundamental in management.     

Besprechungen/Review

Book reviewed in this article: Zeitschriften/Periodicals: Demars, Ch., und M. Goustard (1978: Le “grand chant” d'Hylobates conclor leucogenys. Comparsion avec les émissions sonores homologues d'H. concolor gabriellae et d'H. Klossii (Iles Mentawei, Ouest Sumatra) (Vergleich der Gesänge zweier Unterarten von Schopfgibbons und des Zwergsiamang). Zeitschriften/Periodicals: Polsky, R. H. (1978): The ontogeny of predatory behaviour in the Golden Hamster (Mesocricetus a. suratus). IV. Effects of prolonged exposure, iti, size of prey and selective breeding (Die Entwickliung des Beutefangverhaltens beim Goldhamster. IV. Welchen Einfluß haben längeres Zusammensein mit der Beute, deren Größe, Zeitabstände der Versuche und Genotyp?) Zeitschriften/Periodicals: Fernö, A, (1978). The effect of social isolation on the aggressive and sexual behaviour in a Chichlid Fish, Haplochromis burtoni (Wie beeinflußt Absonderung von Artgenossen das Angriffs- und Paarungsverhalten des Buntbarschs H. b.). Zeitschriften/Periodicals: Lazarus, J., und I. R. Inglis (1978): The breeding behaviour of the Pinkfooted Goose: Parental care and vigilant behaviour during the fledging period (Das Brutverhalten der Kurzschnabelgans: Fursorge und Wachsamkeit der Eltern wahrend der Fuhrungszeit). Zeitschriften/Periodicals: Brémond, J. -C. (1978): Acoustic competition between the song of the Wren (Troglodytes troglodytes) and the songs of other species (Wird beim Zaunköning das Erkennen des Artgesangs durch die Gesänge anderer Arten gestört?) Zeitschriften/Periodicals: Feyereisen, P., und Ch. Blondiau (1978): Comportements de toilettage et activation chez le Rat Balnc (Über den Einfluß von Außenreizen auf das Putzverhalten von Ratten). Zeitschriften/Periodicals: Hennessy, D. F., und D. H. Owings (1978): Snake species discrimination and the role of olfactory cues in the snake-directed behavior of the California Ground Squirrel (Unterscheidung von Schlangenarten und die Bedeutung von Geruchsreizen für das Verhalten Kalifornischer Backenhörnchen gegen Schlangen). Behaviour 65, 115-124. Zeitschriften/Periodicals: Itzkowitz, M. (1978): Group organization of a territorial Damselfish, Eupomacentvus planifrons (Soziale Organisation des territorialen Korallenbarschs Eu. p.). Zeitschriften/Periodicals: Hay, Th. F. (1978): Filial imprinting in the Convict Cichlid Fish Cichlusoma nigrofasciatum (Prägung der Nachfolgcreaktion bei dem Buntbarsch C. n.). Zeitschriften/Periodicals: Kavanau, J. L. (1978): Compulsory regime and control of environment in animal behaviour IV. Light level preferences of Cactus Mice, Pevomyscur evemicus (Erzwungene und selbstbestimmte Tatigkeitseinteilung im Tagesablauf IV. Vorzugshelligkeiten von Kaktusmausen). Zeitschriften/Periodicals: Hyatt, G. W., und M. Slamon 91978): Combat in the Fiddler Crabs Uca pugiltor and U. pugnax: A Quantitative analysis (Kämpfende Winkerkrabben: Eine quantitiative Analyse). Zeitschriften/Periodicals: Walther, F. R. (1978): Quantitative and functional variations of certain behaviour patterns in male Thomson's Gazelle of different social status (Häufigheit und wechselnde Funktionen bestimmter Verhaltensweisen beimännlichen Thomson-Gazellen in verschiedener sozialer Stellung). Zeitschriften/Periodicals: Güttinger, H. R., J. Wolffgramm und F. Thimm (1978): The relationship between species specific song programs and individual learning in songbirds: A study of individual variation in songs of Canaries, Greenfinches, and hybrids between the two species (Arttypische Gesangsprogramme und Lernen bei Singvögeln: Eine Untersuchung der individuellen Variabilität der Gesänge von Kanarienvögeln, Grünlingen und deren Bastarden). Zeitschriften/Periodicals: Kovach, J. K. (1978): Color preferences in Quail chicks: Generalization of the effects of genetic selection (Farbenwahlen unerfahrener Wachtelküken: Ergebnisse künstlicher Selektion). Zeitschriften/Periodicals: Lillehei, R. A., und Ch. T. snowdon (1978): Individual and situational differences in the vocalizations of young Stumptail Macapues (Macaca arctoides) (Persönliche und situationsbedingte Unterschiede in den Lautäaßerungen junger Bärenmakaken). Zeitschriften/Periodicals: Payne, R. B. (1978): Microgeographic variation in songs of Splendid Sunbirds Necturiniu coccinigaster: Population phenetics, habitats, and song dialects (Mikrogeographische Variation der Gesänge von N. C.: Populationsphaenetik, Lebensräume und Dialekte). Zeitschriften/Periodicals: Bailey, K. (1978): Flehmen in the Ring-Tailed Lemur (Lemur catta) (Flchmen beim Katta). Zeitschriften/Periodicals: Horn, E., B. Greiner und I. Horn (1979): The effect of ACTH on habituation of the turning reaction in the toad Bufo bufo L. (Die Wirkung von Corticotropin auf das Abgewöhnen der Zuwendung zu Beuteattrappen bei der Erdkröte). J. Comp. Zeitschriften/Periodicals: Egremont, P., und M. Rothschild (1979): The calulating cormorants (Zählende Kormorane). Zeitschriften/Periodicals: Chauvin-Muckensturm, B. (1974): Y a-t-il utilisation de signaux appris comme moyen de communication chez le Pic Epeiche? (Kann der Buntspecht erlernte Zeichen zur Mitteilung verwenden?). Bücher: Buchholtz , Chr. (1973): Das Lernen bei Tieren. Verhaltensänderungen durch Erfahrung. Bücher: Skinner , B. F. (1973): Wissenschaft und menschliches Verhalten (Science and human behavior, aus dem Amerikanischen von E. Ortmann).     

New Books

Book reviewed in this article: Rosenblatt, J. S. & Snowdon , C. T. (eds.) 1996: Parental Care: Evolution, Mechanisms, and Adaptive Significance. Lehner , P. N. 1996: Handbook of Ethological Methods, 2nd Ed. Denoël , M. 1996: Etude comparée du comportement de cour de deux sousespèces du triton alpestre (A Comparative Study of Courtship Behaviour of Triturus alpestris alpestris Goldschmidt , T. 1996: Darwin's Dreampond. Drama in Lake Victoria. König, B. & Linsenmair , K. (eds.) 1996: Biologische Vielfalt (Beiträge aus Spektrum der Wissenschaft). Bruce V., Green P.G. & Georgeson M.A., 1996: Visual Perception. Physiology, Psychology, and Ecology. Roth, G. & Prinz , W. (eds.) 1996: Kopf-Arbeit. Ricklefs, R. E. & Finch , C. E. 1996: Altern: Evolutionsbiologie und medizinische Forschung. Hausser , J. (ed.) 1995: Säugetiere der Schweiz/Mammifères de la Suisse/Mammiferi della Svizzera — Verbreitung, Biologie, Ökologie/Répartition, Biologie, Ecologie/Distribuzione, Biologia, Ecologia. Birkhäuser Verlag, Basel, Boston, Berlin.     

Effects of tree clumps on soil characteristics in a humid savanna of West Africa (Lamto,Côte d'Ivoire)

The effect of tree clumps on soil characteristics was investigated in a humid savanna (Lamto, Côte d'Ivoire). Soil texture and field capacity were not significantly different under tree clumps compared to open grassland. On the other hand, bulk density was lower under tree clumps, likely due to a greater soil fauna activity under the trees. The pH, available phosphorus, cation exchange capacity, total carbon and total nitrogen contents were higher under tree clumps due to greater organic matter input beneath canopies. Potential soil respiration and mineral nitrogen accumulation were also enhanced, indicating a higher potential microbial activity under tree clumps. Soil water content was slightly lower beneath canopies (from July to November only between 0 and 10 cm depth) when soil moisture was above field capacity. During the other months, no significant difference was measured.     

Reviews

Book Reviewed in this article: Jablonka, E. & Lamb, M. J. 1995: Epigenetic inheritance and evolution: the Lamarckian dimension. Oxford University Press, Oxford. Wagner, W. L. & Funk, V. A. (eds.) 1995: Hawaiian biogeography: evolution on a hot spot archipelago. Bullock, T. H. 1993: How do brains work? Papers of a comparative neuro-physiologist. Series Contemporary Neuroscientists. Klump, G. M., Dooling, R. J., Fay, R. R. & Stebbins, W. C. (eds.) 1995: Methods in comparative psychoacoustics. Nöth, W., ed. 1994: Origins of semiosis: sign evolution in nature and culture. Mouton de Gruyter, Berlin, New York. von Cube, F. 1995: Gefährliche Sicherheit, Die Verhaltensbiologie des Risikos, 2. Aufl, S. Hirzel-Verlag, Stuttgart-Leipzig. Böhme, W., ed. 1993: Handbuch der Reptüien und Amphibien Europas Bd. 3/I: Schlangen (Serpentes) I. Aula Verlag, Wiesbaden.