Influence of ant–grass association on soil microbial activity through organic matter decomposition dynamics in Lamto savannah (Côte d’Ivoire)

This work aims to assess the simultaneous effects of the climate change and the hydromorphological modification of Vridi channel on its hydrochemistry. To best estimate, this fact, the seasonal dynamic of the particle size distribution, pH, redox potential, salinity, conductivity, moisture and organic matter contents of Vridi channel sediments have been followed and compared during two different annual periods, where the climate and the hydromorphology of this estuary have been different. The first annual period, covering the period from April 2014 to March 2015, has been characterized by a climatic regime close to the climatic normal of the study area and, this channel had its former hydromorphology. The second period annual, covering the period from October 2018 to September 2019, has been marked by a disruption of the climatic regime throughout Côte d'Ivoire, and this channel presented its modified hydromorphology. A monthly sampling has been done in this channel during each annual period. All These physical and chemical parameters have been determined by the corresponding AFNOR standards. Results have shown that these superficial sediments, with a predominantly sandy texture over the period from April 2014 to March 2015, have presented a texture predominantly of silt and clays over the period from October 2018 to September 2019. The climate change and the recent hydromorphological modification of this ecosystem had simultaneous very few effects on their pH and redox potential over the study period. On the other hand, they have caused an important increase in their salinity, moisture and organic matter contents and, a decrease in their electrical conductivity over the period from October 2018 to September 2019 relative to those determined in these substrates over the period of April 2014 to March 2015. This fact has certainly affected its biodiversity, especially that of its benthic fauna.

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Effets de six légumineuses spontanées les plus répandues dans les jachères naturelles sur la fertilité des sols dans la région de Daloa (Côte d’Ivoire)

International Journal of Biological and Chemical Sciences ◽

10.4314/ijbcs.v14i3.31 ◽

2020 ◽

Vol 14 (3) ◽

pp. 1052-1064

Author(s):

Nicaise Tetchi Akedrin ◽

Bi Bianuvrin Noël Boué Voui ◽

Odi Faustin Akotto ◽

Sévérin Ake

Keyword(s):

Organic Matter ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Agricultural Land ◽

Physicochemical Characterization ◽

Biological Properties ◽

Cote D’Ivoire ◽

Floristic Inventory ◽

Côte D'ivoire

En Côte d’Ivoire, les pressions exercées sur les terres agricoles ont réduit la durée des jachères naturelles dominées par une végétation herbacée et dont la présence constitue une opportunité pour l’amélioration de la fertilité azotée des sols et la reconstitution minérale des sols dégradés. Pour cette étude, un inventaire floristique des légumineuses herbacées spontanées les plus répandues dans les jachères en constitution ont été effectuées suivie de la caractérisation physicochimique des échantillons du sol sous ces légumineuses ou non (témoin). Au total 6 espèces appartenant à deux familles (Fabaceae et Mimosaceae) et quatre genres (Calopogonium, Centrosema, Crotalaria et Pueraria) ont été inventoriées. Toutes ces espèces sont des Phanérophytes constitués majoritairement de lianes (83%) contre une minorité d’herbacées (17%). Le rapport C/N a varié de 09,5 à 12,8, demeurant ainsi dans la norme (9-12). Les sols prélevés sont quasi riches en matière organique (>1,30 g kg-1) à l’exception de celui recueilli sous Mimosa invisa (1,18±1,1g kg-1). La matière organique intervient dans les mécanismes de la libération de l’azote minéral, donc de la nutrition de la culture associée. Elle influe selon sa nature sur les propriétés physico-chimiques et biologiques du sol et a la capacité d’emmagasiner les réserves en eau.Mots clés : jachères naturelles, légumineuses subligneuses, inventaire, fertilisation, Côte d’Ivoire English title: Effects of six most common spontaneous legumes in natural fallows on soil fertility in the region of Daloa (Côte d’Ivoire)In Côte d'Ivoire, pressures on agricultural land have reduced the duration of natural fallows dominated by herbaceous vegetation and whose presence constitutes an opportunity for improving the nitrogen fertility of soils and the mineral replenishment of degraded soils. For this study, a floristic inventory of the most recurrent spontaneous herbaceous legumes colonizing these fallows in constitution was carried out followed by the physicochemical characterization of the soil samples under these legumes or not (control). A total of six species belonging to two families (Fabaceae and Mimosaceae) and four genera (Calopogonium, Centrosema, Crotalaria and Pueraria) were inventoried. All these species are Phanerophytes made up mainly of lianas (83%) against a minority of herbs (17%). The C / N ratio varied from 09.5 to 12.8, thus remaining within the norm (9-12). The soils sampled are almost rich in organic matter (> 1.30 g kg-1) with the exception of that collected under Mimosa invisa (1.18 ± 1.1 g kg-1). Organic matter is involved in the mechanisms of the release of mineral nitrogen, and therefore of the nutrition of the associated crop. Depending on its nature, it influences the physicochemical and biological properties of the soil and has the capacity to store water reserves.Keywords: Natural fallows, sublimers legumes, inventory, fertilization, Côte d’Ivoire.

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Distribution of microbial activities and organic matter according to particle size in a humid savanna soil (Lamto, Côte d'Ivoire)

Soil Biology and Biochemistry ◽

10.1016/s0038-0717(96)00246-5 ◽

1996 ◽

Vol 28 (12) ◽

pp. 1687-1697 ◽

Cited By ~ 24

Author(s):

H.B. Nacro ◽

D. Benest ◽

L. Abbadie

Keyword(s):

Particle Size ◽

Organic Matter ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Microbial Activities ◽

Cote D’Ivoire ◽

Côte D'ivoire ◽

Humid Savanna ◽

Savanna Soil

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Valorization of Agro-industrial Bio-waste from Seed Cotton in the Restoration of Degraded Soils in the District of Korhogo in Northern Côte d'Ivoire

Journal of Experimental Agriculture International ◽

10.9734/jeai/2019/v41i630444 ◽

2020 ◽

pp. 1-10

Author(s):

Alui Konan Alphonse ◽

Yao Saraka Didier Martial ◽

Oro Zokou Franck ◽

Yao-Kouamé Albert

Keyword(s):

Organic Matter ◽

Grain Yield ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Organic Manure ◽

Corn Yield ◽

Control Soil ◽

Seed Cotton ◽

Cote D’Ivoire ◽

Côte D'ivoire

The objective of this study was to restore degraded soils with organic manure from agro-industrial bio-waste (seed cotton) in the Department of Korhogo in Northern Côte d'Ivoire. The research plots were set up in a Fisher block experimental design with four treatments, namely T0 (control soil), T1 (bio-waste at 1 month of biodegradation), T2 (bio-waste at 3 months of degradation) and T3 (bio-waste at 6 months of degradation). On each of the treatments, bio-waste was applied using spreading technique and the variety F8128 of corn was sown to evaluate the agronomic performance of bio-waste. Four agronomic parameters were measured: Plant height, collar diameter, ear weight and grain yield. Likewise, the physical, physico-chemical and chemical analyses of the soil were performed before sowing and after corn harvesting. The work was carried out from 2018 to 2019 in the district of Korhogo in Northern Côte d'Ivoire. Our study shows significant increase in corn grain yield in each of the treatments (T1 = 2.26 T/ha; T2 = 1.98 T/ha and T3 = 1.48 T/ha) compared to the control (T0 = 1 T/ha). Laboratory analyses of the soil and bio-waste indicate a very low level of organic matter (MO varies from 0.55 to 0.77 g.kg-1) in the soil of the experimental plot and good mineralization of the organic matter in the bio-waste regardless of the decomposition time (C/N varies from 12 to 13). After application of the bio-waste, the organic matter content (T3 = 10.28 g.kg-1; T1 = 23.61 g.kg-1 and T2 = 23.63 g.kg-1) and nitrogen content (T3 = 0.69 g.kg-1; T1 = 1.16 g.kg-1 and T2 = 1.21 g.kg-1) of the various treatments significantly increased compared to the control soil (MO = 0.66 g.kg-1 and N = 0.013 g.kg-1). The pH level increased where the organic manure was applied becoming slightly acidic (5.7 to 6.4) compared to the control that had strong acidic reaction (4.8 to 5.1). Based on our study, it is evident that organic fertilizer has positive effect on corn yield. The seed cotton bio-waste has had an improving effect on the degraded soil of in Northern Côte d’Ivoire.

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Hydrolysable carbohydrate in tropical soils under adjacent forest and savanna vegetation in Lamto, Côte d'Ivoire

Soil Research ◽

10.1071/sr03134 ◽

2005 ◽

Vol 43 (6) ◽

pp. 705 ◽

Cited By ~ 8

Author(s):

Hassan Bismarck Nacro ◽

Marie Christine Larré-Larrouy ◽

Christian Feller ◽

Luc Abbadie

Keyword(s):

Organic Matter ◽

Forest Soils ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Mineral Nutrient ◽

Microbial Activities ◽

Cote D’Ivoire ◽

Rapid Decomposition ◽

Côte D'ivoire ◽

Savanna Soils

Carbohydrates represent 5–25% of the organic matter in soils. They constrain microbial activities and mineral nutrient production in soil and also reflect the whole microorganism community dynamic. The objective of this study was to determine the contents and composition of hydrolysable carbohydrates in soils collected in a forest–savanna mosaic landscape in the region of Lamto (Côte d’Ivoire). Capillary gas chromatography was used to identify and determine carbohydrates in soil profile under 4 tropical ecosystems: gallery and plateau forests, and grass and shrub tree savannas. Forest soils were higher in organic matter than savanna soils (0.50–2.96% C v. 0.53–1.22% C). The carbohydrate-C content of soils, expressed as percentage of total soil organic C, was low, a likely consequence of the tropical climate that promotes a rapid decomposition of surface plant debris. The carbohydrate-C content was higher under savanna soils (5–7%) than under forest soils (3–4%). Glucose, ribose, mannose, xylose, and galactose were the 5 most abundant extractable monosaccharides in all soils. Between them, only xylose and ribose are controlled by the vegetation type. The [(galactose + mannose) : (arabinose + xylose)] and [mannose : xylose] ratios suggested that most soil sugars derive from microbial biomass. The large abundance of microbial carbohydrates indicates intense microbial activities in the soil, and then rapid decomposition of soil organic matter favoured by the long wet season, with high temperatures and soil water availability at the site study. Results suggest clearly that the climate likely controls the amount and composition of carbohydrates in Lamto soils.

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Contribution of Organic Geochemistry and Palynofacies to the Characterization of Organic Matter of Black Shales in Côte d’Ivoire Sedimentary Basin (Northern Gulf of Guinea)

Journal of Chemical Biological and Physical Sciences ◽

10.24214/jcbps.d.8.1.01325 ◽

2018 ◽

Vol 8 (1) ◽

Keyword(s):

Organic Matter ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Sedimentary Basin ◽

Organic Geochemistry ◽

Black Shales ◽

Gulf Of Guinea ◽

Cote D’Ivoire ◽

Côte D'ivoire

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Contribution A La Caracterisation Diagraphique Des Depots Carbonates Du Cretace Du Bassin Sedimentaire De Cote D’ivoire

European Scientific Journal ESJ ◽

10.19044/esj.2016.v12n33p391 ◽

2016 ◽

Vol 12 (33) ◽

pp. 391

Author(s):

Yao Kouadio Cyrille ◽

Kouassi Kouamé Alfred ◽

Boga Atabli Hervé ◽

Monde Sylvain ◽

Digbehi Zéli Bruno ◽

...

Keyword(s):

Organic Matter ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Gamma Ray ◽

Organic Matter Content ◽

Sedimentary Facies ◽

Matter Content ◽

Cote D’Ivoire ◽

Côte D'ivoire ◽

Sonic Log

To know the petrophysical characteristics associated with sedimentary facies gammay ray logs providing information on the natural radioactivity of sedimentary rocks and the sonic logs which document on facies and petrophysical variations rocks were studied. This study focused on three (3) wells (BH-X, DH-X and MR-X) bored in the offshore basin of Abidjan margin (Côte d’Ivoire) for which the lithogy is constituted of clay alternating with sand an sandstone at the base surmounted by limestone and marls which are covered by clay series. It reveals that two deposits phases occurred during the carbonate sedimentation. Through the gamma ray logs, it appears that the clay phases have low radioactivity, which often progress to average values. This radioactivity recorded in clays would be linked to the low organic matter content and leaching reworked elements. In marl phases radioactivity is medium to high indicating a high content of uranium, thorium and potassium deriving from clay minerals. The gamma ray log varies significantly in limestone phases reflecting the heterogeneity of deposits. Strong radioactivity values in some limestone layers are related to their homogeneity and the present of organic matter. Fluctuations result from long-term changes in submarine hydrothermal flow and may indicate significant variations in facies (crystalline limestone, marl and clay). There are more or less dolomitised layers alternating with more homogeneous chemical limestone benches, biogenic limestone debris of organisms and past clay. The sonic log has two phases in the marl and limestone interval. In the marl phase, the acoustic wave velocity is almost constant, but in the limestone phase velocities fluctuate. Indeed, marl interval contains heterogeneous deposits. Generally the velocity is still low in impermeable and little porous clay. In marls, relatively high propagation velocity implies that they are less penetrable as clays because of the presence of fluid. The sonic log fluctuations in the limestone stage reflect the heterogeneity of deposits. Calcareous layers generally have a shorter time of wave propagation, suggesting that they are indurated, recrystallized and homogeneous. By against certain layers are poorly penetrable and show the presence of fluid. The limestone is fractured, so more porous than clay and marl. The porosity may be related to diagenesis after being dessoluted.

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