Université Nazi BONI, Laboratoire d’étude et de recherche sur la fertilité du sol et les systèmes de production, 01 BP: 1091 Bobo-Dioulasso 01, Burkina Faso
The decline in soil fertility and the rainfall deficit strongly limit the cultivation of organic cotton in Burkina Faso. Zaï, a water and soil fertility management technique, can be explored to improve soil and organic cotton productivity. The objective is to determine the effects of zaï on the evolution of the chemical properties of the soil and on the productivity of organic cotton. A trial was implemented in the North Sudanese zone of Burkina Faso in an experimental design in completely randomized Fisher blocks with three (3) treatments including L1 (plowing + 1 t/ha of compost), L5 (plowing + 5 t/ha of compost), ha of compost), Z1 (zaï+1 t/ha of compost). The parameters measured focused on carbon, nitrogen, phosphorus, potassium, exchangeable bases, cation exchange capacity and soil pH and seed cotton yields. The study shows that plowing combined with 5 t/ha compost and zaï combined with 1 t/ha compost significantly improve the chemical properties of the soil. Plowing combined with 5 t/ha of compost (L5) presented the highest average yield (1114±65 kg/ha). Zaï and plowing combined with 1 t/ha of compost recorded identical average yields (782±81 kg/ha and 752±23 kg/ha). Zaï combined with 1 t/ha of compost can be vulgarized in the North Sudanese zone of Burkina Faso and can be a means of adapting to increasingly difficult rainfall conditions marked by pockets of drought.
The high demand for labor and the low availability of organic fertilizer reduce the effectiveness of manual zaï. To overcome these constraints, the effect of adding Loudetia-based compost enriched with Burkina natural phosphate (Burkina phosphate) under mechanized zaï on soil moisture content and sorghum yield was evaluated in 2022 and 2023 at Arbollé in northern Burkina Faso, using an experimental system of scattered blocks on eight (8) farmers.: T0 = control; T1 = manual zaï + producer organic manure + microdose; T2 = manual zaï + producer organic manure; T3 = mechanized zaï + producer organic manure + microdose; T4 = manual zaï + Loudetia compost; T5 = manual zaï + Loudetia compost + microdose and T6 = mechanized zaï + Loudetia compost + microdose. Mechanized zaï + producer’s organic manure + microdose (T3) and mechanized zaï + Loudetia compost enriched with Burkina phosphate (BP) + microdose (T6) gave the best grain yields ranging from 1213.13 k/ha to 1533.67 kg/ha, and the best soil moisture levels of 14.06% and 13.74% respectively at 45 JAS. Also, manual zaï + Loudetia compost enriched with BP + microdose (T5), made it possible to obtain average yields of 1004.62 kg/ha. Mechanized zaï + Loudetia compost + microdose could therefore help increase sorghum productivity. The effectiveness of this combination on yield could be improved by adding BP to the compost.
The waste is used to fertilise fields. Their pre-treatment can impact on human health and the environment. A study was carried in Bobo-Dioulasso, precisely in Kuinima and Dogona, with the main objective of assessing the impact of waste treatment methods on the environment and health. The data was obtained from individual interviews with farm managers.
The results show that 56.67% of the producers practise sorting followed by incineration and 20% practised sorting only, 23.33% of the producers did not perform any treatment. Sorting caused injuries to 33.33% of the producers, 10% were harassed by insects. As for the impact of the treatment methods on the environment, 83.33% of the producers who sorted their waste had their fields invaded by new weed species, compared to 76.47% of those who sorted and incinerated. For 88.23% and 66.67% of the producers who were sorting followed by incineration and sorting only respectively, the crop yield was good. From these results, we can conclude that the waste treatment methods used by producers have negative effects on the environment and human health.
Soil fauna significantly influences soil properties. Organic and inorganic fertilization in agriculture, including the amendment with phosphate rock, may affect its presence in soils. This study evaluated the effect of calcined phosphate rock associated with organic matter on the abundance and diversity of soil macrofauna in semi-arid areas of Burkina Faso. Nine treatments were replicated four times each and applied in a complete randomized block design in sorghum and cowpea fields. These treatments were: absolute control (Control) without fertilizer, control with organic matter only (OM), Burkina Phosphate Rock (BPR) with 23 P ha-1, calcined phosphate rock (CPR with 23 P kg ha-1), Triple super phosphate (TSP), complex fertilizer (NPK), CPR ½ +TSP ½, CPR ¾ +TSP ¼, CPR ¼ +TSP ¾ Urea provided N, and KCl supplied K in the BPR and TSP treatments. P was supplied by Triple Super Phosphate (TSP) in the TSP treatment. K and P were supplied by the complex fertilizer NPK in NPK treatment. Results showed that BPR and CPR did not significantly (P˃0.05) improve soil fauna abundance and diversity after two years. Four orders, Coleoptera, Haplotaxida, Hymenoptera, and Isoptera, were largely dominant (more than 50 %) in all treatments, crops, and years. The population diversity of soil macrofauna rises from 0.98 (2021) to 1.49 (2022) in the sorghum field and from 1.16 (2021) to 1.63 (2022) in the cowpea field. Soil macrofauna numbers rise from 24.64 ind/m2 (2021) to 39.59 Ind/m2 (2022) in the cowpea field. Our findings suggest that cultivated soil fauna can be managed more appropriately with fertilizers from phosphate rock by combining organic matter application and cereal-legume associations.
Due to its multiple functions, soil macrofauna plays a major role in the functioning of agroecosystems. However, its abundance and diversity can be influenced by various human activities such as agricultural practices. This study, initiated on ferric lixisols in the Sudano-Sahelian zone of Burkina Faso, aims to evaluate the effects of four agroecological practices on soil macrofauna. So, forty farmers' plots were sampled, based on a typology of cropping practices, associating water and soil conservation techniques (stone barriers) with generalized or localized (zaï) application of organic matter. Generalized input of organic matter is combined with mineral fertilization by microdose or not and localized input is combined with crop rotation or not. Macrofauna was collected, sixty days after sowing, using the monolith method. Three (3) monoliths were collected per plot. Manually sorted macrofauna was identified in the laboratory. The results allowed that thirty-six (36) families were identified whom the best abundant are: Termitidae (35 %), Formicidae (18 %) and Iulidae (7.7 %). Functionally, saprophages constitute 61.4 % of the population against 16.6 % of phytophagous, 13.9% of predators and 7.6 % of geophagous. Agroecological practices with uniform application of organic manure yielded the highest number of invertebrates (62.2 %) compared to localized application (37.8 %). The use of organic manure as an agroecological practice allows for better colonization of the soil by living organisms, provided that it is evenly distributed throughout the plot.
Knowledge of the characteristics of upland rice cultivation systems is a lever for the development of rice cultivation in Burkina Faso. This study aims to highlight the typology of upland rice cultivation systems in three localities: East, Hauts Bassins and Central Plateau regions of Burkina Faso. A survey was carried out among a sample of 293 producers in the localities concerned. The Multiple Correspondent Analysis identified three upland cultivation systems: the low-intensive Upland rice cultivation system with rotation (SCRPS1); the Intensive Upland Rice Cultivation System (SCRPS2) and the low-Intensive Upland Rice Cultivation System without rotation (SCRPS3). Elements that make it possible to distinguish the systems are: age, sex, level of education of the farmer, upland rice area, equipment, crop rotation, type, quantity and the number of fertilizers used in upland rice system. The practices of cropping systems differ from one locality to another. In short, the SCRPS1 type is the most practiced by producers and the SCRPS2 type with a high yield (2759.04 kg / ha) presents itself as an interesting prospect to promote for rice production generating income for an improvement of income women farmers.
The ability of certain vegetable crops has been proven in the accumulation of heavy metals. Among these species is lettuce (Lactuca sativa L.). In Burkina Faso, the ability of some local species to accumulate heavy metals has also been demonstrated. Among these species we have lemongrass (Cymbopogon citratus). To promote their introduction into cropping systems, a study was initiated to evaluate the effects of lettuce-citronella associations on the transfer of heavy metals in lettuce organs and soil chemical parameters. The experimental setup was in completely randomized factorial blocks comprising three treatments and three replicates. Treatments compared pure lettuce (T0) culture with alternating lettuce-lemongrass combinations on the same line (T1) and citronella lettuce where lemongrass plants are placed in interline lettuce (T2). The effects of these associations on the transfer of heavy metals in lettuce were evaluated. Their effects on soil chemical parameters were also evaluated.
The results obtained show a significant reduction (p> 0.05) of the amount of lead accumulated in the leaves of lettuce compared to that of lemongrass for treatments T1 and T2. As for the chemical parameters of the soil; cation exchange capacity, organic matter, assimilable phosphorus and total potassium were significantly affected by the associated culture compared to the pure culture of lettuce. The promotion of lettuce-citronella associations can be considered for the reduction of lead accumulation by lettuce.
Soil management, such as organic amendments application, may play an important role in the effects of pesticide residues on soil microbial activity. In order to evaluate these effects, a field experiment was set up. Deltamethrin and profenofos were used for treatment and applied at the recommended dose. Manure, urban waste compost and green waste compost were provided at a rate of 20 t / ha. Respiratory activity was measured every hour. After 7 days of incubation, glucose, nitrogen and phosphorus were added. The interaction between organic amendments and pesticides have showed that only treatment with deltamethrin-manure have significantly decreased the basal respiration (RB) with 0.038 mg C-CO2 g-1 soil compared to the pesticide control (0.058 mg C-CO2 g-1 soil). Profenofos- cattle manure and profenofos-compost treatments have significantly inhibited SIR (Substrate Induction Respiration) compared to profenofos-control (0.097). Both deltamethrin and profenofos have significantly increased the lag time and maximal respiration compared to the control (P˂0.05). The organic amendments and pesticides interaction have significantly reduced the lag time (11h), compared to the pesticide control (26h). Cattle manure has reduced microbial catabolism in the presence of deltamethrin, but urban waste compost and green waste compost have stimulated microbial catabolism (BR) and anabolism (SIR).
Soil fertility is an indicator of good agricultural production and consequently of the agricultural activity of a locality. In the Sahel and in particular in the basin of the Thies region, soils gradually lose their production capacity. Desertification caused by the combined and simultaneous action of climatic and anthropogenic factors continues to progress. However, studies by the National Agency for Statistics and Demography (ANSD) reveal that the extent of farms in the different regions of Senegal is not correlated with the potential of land production. The objective of this study is to determine whether the areas cultivated in the groundnut basin of the Thies region are related to soil fertility. The methodology adopted is based on a physico-chemical soil analysis to determine a possible relationship between soil fertility and the extent of agricultural land. Field studies were also carried out on the adaptation strategies developed by local producers in the face of this decline in soil fertility. The Bernoulli formula was used for the selection of the study sample. The results of the soil physico-chemical analysis reveal that the areas cultivated by farmers are larger in the less fertile lands. Therefore, the control methods undertaken in the face of declining soil fertility have been fruitful.