جستجوی مقالات مرتبط با کلیدواژه « soil parameters » در نشریات گروه « آبخیزداری، بیابان، محیط زیست، مرتع »

Trees and shrubs can act as nurse plants that facilitate the growth and development of other herbaceous species under their canopies and induced the autogenic development of soil parameters. Therefore, we studied the effect of Crataegus pseudomelanicarpa on carbon sequestration (total carbon and particulate organic matter) in two grazed and ungrazed areas during the two seasons (spring and autumn) in central Alborz, Pasperes village, Noor rangelands, Iran. Fifteen individual trees (according to the surface of each region, five in the ungrazed and ten in the grazed areas) were selected. Soil samples were taken in spring and autumn in 2017 under woody canopy (patch) and outside the canopy (interpatch) of individual trees. Soil samples were tested for total carbon (TC) and particulate organic matter (POM). The results showed that the value of TC was higher in the autumn than the spring and conversely, POM was significantly higher in the spring than the autumn. Generally the results showed that the presence of the shrubs in both grazed and ungrazed areas improved the values of TC and POM in both seasons. In the grazed area, POM (24.43 g kg-1 vs. 15.41 g kg-1 in the spring and 11.71 g kg-1 vs. 8.59 g kg-1 in the autumn) and TC (1.53% vs. 1.35% in the spring and 1.61% vs. 1.58% in the autumn) had significantly higher values in patches than interpatches, while in the ungrazed area, these differences were less pronounced or not significant between patches and interpatches. It was concluded that the facilitated role of woody species in the conservation of soil carbon is more prominent in the grazed compared with ungrazed grasslands. It was emphasized on conservation of woody species in the rangelands particularly in the grazed areas.

This study aimed to trace changing patterns of vegetation attributes in association with soil physicochemical properties at selected seasonal grazing sites central Sudan (Khartoum State) namely Tundub, El-Farish, Abuseweid, Medaisees, Buhat, Abudolou’a Km 72 and Abudolou’a Km 42. A combination of sampling procedures was followed to sample vegetation and soil. Comparisons between sites were made using one way ANOVA, followed by Duncan’s Multiple Range Test (DMRT). Pearson’s correlation analysis was made between plant attributes and soil physicochemical properties. Study sites varied significantly in plant productivity, diversity and soil properties. Abuseweid site achieved the highest herbaceous diversity, density and total dry matter productivity values. Tundub and Buhat were higher in woody perennial attributes having the highest browse productivity and percentage canopy covers. Tundub exceeded other sites in plant ash, Ca, Mg and K contents followed by Medaisees every time. Medaisees exceeded others in plant P and N contents, given that Tundub, Medaisees and Buhat were higher in perennial woody attributes. The sand dune sites Abudolou’a Km 42 and Km 72 were the poorest sites in all vegetation attributes measured. Variation between sites in plant attributes was strongly related to variation in soil physical and chemical properties. Two groups of soil physicochemical factors regarding their associations with vegetation attributes were observed, soil Na, N, clay, water holding capacity (WHC), EC, OC, OM and silt contents were positively correlated to vegetation attributes; pH, Ca and sand contents negatively correlated to vegetation attributes.