This work aims to evaluate the antimalarial biological activities of medicinal plant extracts namely Artemisia annua, Alisicarpus ovalifolius and Securidaka longepediculata. The phytochemical analysis of the extracts of these plants revealed the presence of saponins, alkaloids, flavonoids, quinones, phenols and terpenes. Toxicity tests according to the method proposed by OECD have made it possible to conclude that the plant extracts are not toxic. The tests were carried out on mice, inoculated intraperitoneally with Plasmodium berghei. These animals were divided into eleven groups of five, nine of which each received a dose of the extract to be tested and the other two, distilled water for the negative control and arthemether for the positive control. The different extracts showed various antimalarial activities using the four-day Peters test on infected mice. Artemisia annua gave the highest parasitaemia reduction percentages with 87.2; 96.8 and 96% respectively at doses of 100, 250 and 500 mg/kg, while Alisicarpus ovalifolius recorded 61.6; 71.20 and 80.8% respectively at the same doses. Securidaka longepediculata extracts gave low percentage reductions in parasitaemia. Statistical analysis reveals that the extracts showed a significant difference compared to the negative control (P<0.05).

The ecology of a species is a fundamental aspect in its sustainable management. The objective is to study the ecological and floristic characteristics of plant formations with D. mespiliformis. The study was conducted in western Niger along the main tributaries of the Niger River crossing two agroecologicals compartments. Abiotic factors and forestry data where collected in 220 plots of 2500 m2. Thus, the species is present in all types of soil in the area near streams. The area is moderately diverse with 41 woody species dominated by D. mespiliformis with 50% of Importance Value Index. The Shannon diversity index was 2.61 in Dargol and 2.19 in Goroubi and the Sorensen similarity index between the two zones was 0.62. The density of D. mespiliformis per hectare is 46.04 in Dargol and 33.19 in Goroubi. The demographic structure of its population of all species shows a dominance of small diameter individuals evolving into sawtooth characterized by anthropogenic pressure. These results constitute a scientific basis for the sustainable management of this food and multi-use species, which is one of the species in decline in the area.

The management of protected areas requires constant adaptation to current context, managers must decide on methods for assessing and monitoring values of their conservation area. This choice must be based on simple methods that are efficient and less costly in terms of time and costs in a scarce financial resources context. Fourteen (14) Bushnell-branded trap cameras were deployed, which were used to collect data throughout the follow-up period which runs from February to April 2018. The sampling points were chosen at random and the choice of the location of the camera in the sampled part is based on certain essential criteria for a good follow-up. Indeed, it would be necessary to take into account the trails used by wildlife and the availability of a hang support for cameras. Data collected during the follow-up period concern three hundred and sixty-seven (367) nights traps or 8808 hours. Two (02) of the fourteen (14) trap cameras deployed for the collection system did not work: one is stolen and the other do not fonction well. Nineteen thousand six hundred and forty-six (19646) pictures of mammalian fauna were captured by the trapping cameras in which twenty-nine (29) species were identified. The diversity index varied from 2.38 bits in February to 3.89 bits in March respectively; it fell in April with 1.65 bits. Pielou's equitability was respectively 0.51, 0.81 and 0.37 for above mentioned months. Animal density estimated from distance sampling points transect showed fluctuating densities (4.87; 3.40 and 5.23 individuals per ha) depending on the month (February, March and April).

Forest banquettes and half-moon techniques associated with plantations of woody species are commonly used in Niger to restore degraded lands. To assess the impacts of these anti-erosion structures on the physicochemical characteristics of the soil and plant diversity, an expimental study was carried out in the rural commune of Simiri on a plateau site fitted out with a forest banquette and a glacis site with forest half-moons. An undeveloped control zone was considered for each restoration site. The soil moisture at the structures was regularly recorded for 30 months. Soil samples under the crown of the planted plants were taken and analyzed in the laboratory. A floristic inventory of spontaneous species was carried out on restoration sites and control areas. Finally, the herbaceous biomass was evaluated. It emerges from this experiment that forest benches and half-moons significantly improve soil moisture and texture as well as organic carbon under the crown of planted plants. These conditions allowed the development of spontaneous plant diversity. These results highlight the effectiveness of forest banquettes and half-moons in restoring degraded lands of plateaus and glacis.

The study aims to characterize the demographic structure of the vegetation of the protected forest Baban Rafi located in the department Madarounfa 50 km south of Maradi. The data were collected based on a forest inventory in 105 plots of 1000 m² installed on 17 transects varying in length from 1 to 5 km. Data analysis has established the list of plants, species diversity, the horizontal structure, vertical structure, and regeneration of woody plants. A total of 52 woody species distributed in 40 genera and 21 families were inventoried. The best-represented families are respectively the Combretaceae and Fabaceae-Mimosoideae. The most important species are Guiera senegalensis, Combretum micranthum, and Combretum nigricans. The average density of woody species (994.86 ± 343.71 individuals / ha) and that of regeneration (17,092.95 ± 10,431.80 seedlings / ha) indicate a good regeneration capacity of the forest. The values of the index of Shannon and evenness Pielou are 3.8 bits and 0.68 bits respectively. The diameter structures of the woody stand and those of the dominant species show a concentration of young individuals of the class from 5 to 10 m. Those in height show a predominance of individuals of heights between 1 and 5 m. These results provide additional information on the current state of woody stands in the Baban Rafi forest and can be used in biodiversity conservation and the management of protected forests in Niger.

In Niger, after the severe droughts of the 1970s and 1980s, several development projects promoting trees on farms and creating village woods were implemented. The objective of this study is to analyze the structure and diversity of stands of woody legumes (Faidherbia albida) in the department of Dogondoutchi which is a successful case of environmental policy, in order to serve as a reference for the orientation of future development works. The data were obtained on the one hand through a floristic inventory on a perpendicular transect following the four cardinal points on 60 plots of 2500 m², and on the other hand through individual surveys of 90 farmers. The results obtained show an overall specific richness of 19 species divided into 10 families in the study area. Mimosaceae (52%) are the families most encountered with Faidherbia albida (49%). The current dynamics of this Faidherbia albida stand is regressive because of the poor regeneration and aging of the subjects. Analysis of survey data shows that the regressive dynamics are due to parasitic pressure. Therefore, urgent measures must be taken by the state to eradicate this parasitic pressure.

Objective : This study is conducted on the Goulbi N'Kaba Valley in Niger. The objective of this study is to determine the pastoral value and productivity of this area. Methodology : The methodological approach is focused on the sites of pastoral discharge sites and on two (2) transects (GB-GT and KH-DK), approximately 6.5 km long, running through the adjacent terraces (fields), the corridors of passage and the sylvo-pastoral zone (ZSP) of the valley. Phytosociological surveys based on abundance (number) and dominance (recovery) of species, and the harvest of phytomass were regularly made in plots of 2500 m². The quadratic points aligned method and the integral biomass harvest method were applied. Forage and pastoral values, productivities and load capacities were appreciated. Results : Forage values (legumes, graminoids, phorbes) of pastoral discharge sites in 2004 (16 ; 22 ; 51) are higher than those in 2014 (8 ; 10 ; 29). This trend is maintained at the level of adjacent terraces (with 24, 22, 63 in 2004 against 17 ; 12 ; 40 in 2014) and corridors of passage (with 22 ; 21 ; 60 in 2004 against 15 ; 15 ; 11 in 2014). Pastoral values (2004 and 2014) move in the same direction as forage values (2004 and 2014). The productivity of species under crown is greater than that of species outside crowns. The productivities of 2004 are higher than those of 2014 on pastoral discharge sites and corridors of passage. Nevertheless those of 2014 (1398.6 ± 444.5 kg MS / ha) are higher than those of 2004 (1127.8 ± 608.4 kg MS / ha) on the adjacent terraces of the Goulbi N’Kaba valley. The carrying capacity follows the same trend as productivity in the Goulbi N'Kaba valley, but with much smaller values. Conclusion : Pasture and pastoral values and productivities revealed the deterioration of rangelands of pastoral discharge sites, adjacent terraces and passage corridors in the Goulbi N'Kaba valley from 2004 to 2014.