The aim of this study was to quantify the current soil organic carbon stock under different types of savannah agrosystems in the Sudano-Sahelian zone of Cameroon in the context of greenhouse gas emissions and land degradation. It is so crucial for combating climate change and improving ecological restoration. Random field sampling was carried out on 0-10, 10-20 and 20-30 cm depth, then were collected in four types of savannah agrosystems. Soil bulk density, pH, moisture content, CEC, exchangeable bases, particle size distribution and soil organic carbon were determined using standard laboratory procedures and calculations. The results of the study did not reveal a significant difference in soil organic carbon stock between different types of savannah agrosystems (P>0.05). Soils of Tamarindus indica savannah agrosystems in recorded higher values SCOS (36.03 ± 3.31 tC/ha), Prosopis africana (33.40 ± 3.27 tC/ha), Haematostaphis barterii (31.83 ± 3.21 tC/ha) and Detarium microcarpum (31.19 ± 3.19 tC/ha) savannah agrosystems. Similarly, SCOS decreased with soil depth in all types of savannah agrosystems. Results showed a positive and significant (P<0.05) correlation between soil organic carbon stock with basal area, biovolume, bulk density, moisture content, C/N ratio, Ca 2+ , Mg 2+ , OM; negative and significant (P<0.05) with Soil pH, Total Nitrogen, Na + but negative and non-significant (P>0.05) with Density, K + , CEC, Sand %, Silt %, Clay %, Silt + Clay %. The results show the potential contribution of savannah agrosystems to improve soil organic carbon sequestration and environmental protection.

The vegetation and the afforestation of agricultural land non-forest represent a potential increase in carbon stocks which could, under certain conditions and within certain limits, compensate part of the emissions resulting from the use of fossil fuels and deforestations. Quantification of stocks of biomass and carbon dioxide contained in agroforestry systems has become an international priority within the framework of the implementation of REDD+ mechanism. Estimates of stocks of carbon in woody biomass, dead organic matter, belowground biomass, litter, herbaceous and lianas plant biomass were incorporated in allometric equation based on non-destructive method. The total carbon stock evaluated in the parkland of Tectona grandis was 207.34 ton/3ha out of which woody biomass accounted for 130.19 ton/3ha belowground biomass (40.4 ton/3ha), dead organic matter (22.85 ton/3ha), litter (9.09 ton/3ha), herbaceous plant biomass (2.28 ton/3ha) and lianas (2.53 ton/3ha). The aboveground biomass therefore contributed approximately 62.80 % of the total stock of carbon assessed. This show the considerable contribution of Tectona grandis parkland to climate change mitigation in Cameroon.

The aim of this study was to quantify the current soil organic carbon stock under different age ranges of cashew agroecosystems in the Sudano-Sahelian zone of Cameroon in the context of greenhouse gas emissions and land degradation. It is so crucial for combating climate change and improving ecological restoration. Random field sampling was carried out on 0-10, 10-20 and 20-30 cm depths were collected in three age groups (0-10; 10-20; over 20 years old) of Cashew agroecosystems. Soil bulk density, Soil reaction (pH), moisture content, total nitrogen, C/N ratio, particle size distribution and soil organic carbon were determined using standard laboratory procedures and calculations. The results of the study did not reveal a significant difference in soil organic carbon stock across the different age groups of the cashew agroecosystems (P>0.05). The highest values of soil organic carbon stocks were observed in the 0-10 cm depth. Soils under plots with over 20 cashew agroecosystems in Bénoué subdivisions recorded higher SOCS values (36.30±2.92 tC/ha). Similarly, the SOCS decreased with soil depth in all three age groups of Cashew agroecosystems. The mean SOC concentrations (%) ranged from 0.20±0.02-0.41±0.10%. Soil organic carbon stock ranged from 16.45±0.73-37.04±2.32 tC/ha depending on depth between the three age ranges of Cashew agroecosystems studied in the four subdivisions. The Cashew agroecosystems soils with high C stock are those with sandy loamy texture (25.79±2.29 tC/ha). Results showed a positive and significant (P<0.05) correlation between soil organic C stock with bulk density, moisture content, C/N ratio, SOC; negative and significant (P<0.05) with Soil reaction (pH), Total Nitrogen, but negative and non-significant (P>0.05) with % Sand, % Silt, % Clay, % Silt + Clay. The results show the potential contribution of Cashew agroecosystems to improve soil organic carbon sequestration and environmental protection. This information will be necessary for developing appropriate technological and political solutions to increase agricultural sustainability and combat environmental degradation in the Sudano-Sahelian zone of Cameroon.

The present study aims to quantify carbon storage in different biomass pools of Psidium guajava agroecosystems in the northern region of Cameroon in order to understand their contribution to climate change mitigation. The destructive and non-destructive methods were used according to a random complete Fisher block device with 4 repetitions. The results obtained show that the average total carbon stock of Psidium guajava agroecosystems in the northern zone of Cameroon is 44.44 ± 4.96 tC/ha. The total carbon stock varies by region; in the Adamawa region (46.30 ± 4.91 tC/ha); North (46.34 ± 4.93 tC/ha) and Far North (40.69 ± 4.98 tC/ha). These results show the considerable contribution of Psidium guajava agroecosystems in the fight against the mitigation of climate change in the Septentrion zone of Cameroon.

The general objective of the study is to characterize the woody vegetation of 05 agroforestry parkland in the Sudano-Sahelian zone of Cameroon. A total of 40 floristic surveys of 200  20 m were carried out. A total of 33 species in 20 families and 31 genera were recorded. The dendrometric survey method enabled us to characterize the vegetation of the agroforestry parks. The dendrometric parameters and indices calculated according to the agroforestry parks vary from one park to another. Thus, density varies from 108±2.98-223±8.01 individuals/ha, recovery from 6.11±0.21-10.12±0.31%, basal area from 6.54±1.12 to 10.05±1.87 m²/ha, biovolume from 20.09±2.22-38.54±3.76 m 3 /ha, total height from 2.11±0.01-5.06±0.04 m, natural regeneration rate from 2.11±0.52-7.40±1.09%. The Shannon index varies from 1.36±0.20-2±0.29 bits, Pielou index from 0.14±0.07-0.35±0.18 and Simpson index from 0.82±0.02-0.97±0.03. The species with the highest SIV and SIR are Combretum glutinosum, Combretum adenogonium, Sclerocarya birrea, Prosopis africana, Entada africana, Anacardium occidentale, Burkea africana, Maytenus senegalensis, Ficus glumosa. The Mimosaceae, Caesalpiniaceae, Combretaceae show a high representativeness in relation to their family importance value. The diameter structure showed a predominance of young individuals and the height structure showed a predominance of individuals of class [4-6 m]. These results can be used as a reference in monitoring the vegetation dynamics of agroforestry parks subject to recurrent droughts and anthropogenic pressures. This study provides a better understanding of the vegetation in agroforestry parks in order to better manage these plant resources.

The present study investigated the floristic structure and ecological role of Rourea afzelii stands insavannah, forest galleries and swampy areas to Cameroon. An 80 m x 50 m transect method wasundertaken to measure floristic diversity using Shannon index, Pielou equitability, Simpson’s indexand the importance value index. The structure of Rourea afzelii stands is determined by density,basal area and biovolume. The results of this study show that Rourea afzelii stands are morediversified in savannah with a Shannon diversity index (ISH =4 ± 0.03bit). The highest log stabilityof Rourea afzelii stands is observed in the savannah (EQ=0.75 ± 0.008). The Simpson index of theRourea afzelii stands is larger in the forest gallery (D=0.088 ± 0.0022). Rourea afzelii Stands aredenser in savannah (113 ± 2.54 individuals/ha). The basal area and biovolume of Rourea afzeliistands are very high in swamp area (St=15.75 ± 0.02 m2/ha, Biov=9.08 ± 0.12 m3/ha). The diametricstructure has an asymmetrical “L” shaped appearance, indicating a strong regeneration of Roureaafzelii Stands in the three sites studied. Rourea afzelii Stands in forest galleries sequestered morecarbon (26.41 ± 0.0015 ton C/ha) than those in savannahs and swampy areas. This valuecorresponds to sequestration of carbon dioxide of 96.92 ± 0.82 ton CO2/ha. Economically, thiscorresponds to the CDM carbon price (290.77± 3.332 Euros/ha), a Voluntary Market Carbon Priceof 455.54 ± 1.908 Euros/ha, a REDD + carbon price of 9692 ± 8.152 Euros/ha. In conclusion, theresults of this study can be used in the context of protection and conservation as well as thedomestication of such a species.

The present work has been done to provide basic data for a better conservation and valorization ofKhaya senegalensis stands in Sudano-Sahelian zone of Cameroon. A 100 m x 50 m transectmethod was undertaken to measure floristic diversity through the use of species richness,Shannon index, Pielou equitability, Simpson index, importance value index and importance valuefamily. The vegetation structure is determined by density, basal area and biovolume. Theinventory included trees with a dbh ?10 cm on an area of 1 ha per plot. A total of 6743individuals distributed in 24 families, 33 genera and 54 species were inventoried in all Khayasenegalensis stands studied. Statistical analysis showed significant differences, Shannon index,Simpson index, Pielou equitability, density, basal area, biovolume, species richness, heights class,diameters class, circumferences class but does not certify a significant difference of importancevalue index among in the villages. The undergrowth of Khaya senegalensis stands is more diverseat Bamé with a Shannon diversity index (ISH=5.87 ± 0.12 bit). The greatest of Pielou equitabilityis observed at Bamé (EQ=0.80 ± 0.01). The largest of Simpson index is recorded at Bamé(D=0.098 ± 0.001). Khaya senegalensis Stands are denser at Bamé (194 ± 3.12 individuals/ha).The basal area and biovolume of Khaya senegalensis stands are very high at Bamé (BA=25.87 ±0.06 m2/ha and Biovolume =15.32 ± 0.012 m3/ha). The species importance value is maximal in allthe studied villages (SIV=300 ± 71.45). The importance value index of species revealed a cleardominance in the undergrowth of Khaya senegalensis stands are Combretum adenogonium;Acacia senegal; Terminalia laxiflora; Guiera senegalensis; Acacia nilotica; Entada Africana.The vertical structure has three aspects, like the L (Dbh), asymmetric (height) and dissymmetrical(circumference) structures attesting to a strong regeneration of the understory ligneous woods ofKhaya senegalensis stands studied.

The attribution of community forests to local populations has emerged as a new participative management system of plant biodiversity in Cameroon. Further to the intensification of anthropogenic activities in these forests, the logging impact on this biodiversity remains poorly known. This study was conducted in two different community forests located in the Kompia and Nkolenyeng villages, respectively. It aims to provide information on the state of the flora and plant structure of the community forests subjected to logging activities. Floristic inventories were carried out in nine biotope types using the variable-area sampling method. A total of 2772 individuals with dbh ≥ 10 cm were recorded in the community forests. In the whole biotopes, the species richness ranges from 19 to 98 species, the Shannon diversity index from 3.63 to 5.99 and the Pielou evenness from 0.65 to 0.93. The density of trees ranges from 73 ± 27 to 661 ± 119 stems ha-1 , the basal area from 15.68 ± 13.14 to 70.05 ± 28.76 m² ha-1 , the mean diameter of 18.85 ± 4.80 to 57.39 ± 20.70 cm and the canopy height from 12.26 ± 1.22 to 25.18 ± 1.02 m, on the average between biotopes. The two community forests showed decrease in tree density, a proliferation of the pioneer species, increase of small-diameter light-demanding species, a scarcity of large-diameter trees, and lowering of canopy height. These changes could compromise the sustainable management of these forests and their ability to ensure long-term local development. The large number of useful species identified in the two community forests is a reason to reinforce the preservation and management measures of the plant biodiversity of these forest areas.