Elaheh Fahimipour; Jamshid Ghorbani; Ghodratollah Heydari
Abstract
Soil seed bank has an important role in vegetation restoration following cessation of disturbance. In this study, the soil seed bank richness and diversity were investigated in semi-steppic rangeland with a history of land conversion into cultivation in Charmahal-Bakhtiari province. Land-use changes ...
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Soil seed bank has an important role in vegetation restoration following cessation of disturbance. In this study, the soil seed bank richness and diversity were investigated in semi-steppic rangeland with a history of land conversion into cultivation in Charmahal-Bakhtiari province. Land-use changes were identified in grassland and shrubland and then were classified into four groups according to the time since abandonment including < 5, 5-15, 15-25 and > 25 years. Aspect was considered in each group. Soil was sampled and seed bank was identified using seedling germination method in glasshouse. Then, seed bank richness and diversity indices were calculated. Results showed that in seed bank the number of perrenilas was greater than annuals. In both grassland and shrubland time since abandonment significantly influenced the soil seed bank richness and diversity. In grassland soil seed bank richness and diversity decreased with time of abandonment but in area with more than 25 yrs of abandonment seed abnk richness and diversity significantly increased. Aspect significantly affected both seed bank richness and diversity in shrubland. North slpoe showed fluctuation in seed bank richness and diversity during abandonment while an increase was found in west slope and a reduction in south and east slopes. In both sites the soil seed bank indices significantly increased shortly after abandonment (<5 yrs) but seed bank richness and diversity showed resilient in >25 yrs in grassland and >15 yrs in shrubland.
hamed farzi; reza tamartash; zeinab jafarian; Mohammad reza Tatian
Abstract
Restoring vegetation can change the structure and dynamics of vegetation, as well as the change in other parts of the ecosystem such as soil. The success of recovery efforts will be achieved when assessing the characteristics of ecosystems over time and comparing with the control areas. Therefore, the ...
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Restoring vegetation can change the structure and dynamics of vegetation, as well as the change in other parts of the ecosystem such as soil. The success of recovery efforts will be achieved when assessing the characteristics of ecosystems over time and comparing with the control areas. Therefore, the aim of this study was to investigate the effects of reducing plant cover and soil carbonation in rangelands of the southern slopes of central Alborz. Sampling from vegetation during the growing season of May and May was done in a systematic-random manner in 400 plots of 2 m2, along 40 transects of 100 meters. In each plot, crown cover percentage, species presence, functional characteristics of species including vegetative form, distribution type, pollination type and biological form were recorded. During each transect, two soil samples were harvested at different depths of 0-15 and 30-30 cm in different treatment and control areas. A total of 160 soil samples were collected from four different regenerative operations including clamping, seeding, grazing management, grazing and a natural rangeland as a control site. . showed that biological measures significantly changed the canopy cover percentage of three herbs. In the meanwhile, the Graminea strain in the regeneration zone and the legumes of Leguminosae and Cruciferae in the area had a significantly higher mean canopy percentage. The percentage of organic matter and the amount of organic carbon sequstration in the two depths of the soil and bottom of the soil in different biological operations at level have a significant difference.
Hossein Bashari; Mostafa Tarkesh; Tayebeh Shahabadi; Mohammad Reza Mosadeghi
Abstract
Abstract
This study aimed to investigate the effects of urban wastewater on some soil physical and chemical properties in Segzi, East Isfahan. Six sites were selected considering the planted species (Haloxylon persicum and Nitraria schoberi) and irrigation types (control or no irrigation, water logged ...
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Abstract
This study aimed to investigate the effects of urban wastewater on some soil physical and chemical properties in Segzi, East Isfahan. Six sites were selected considering the planted species (Haloxylon persicum and Nitraria schoberi) and irrigation types (control or no irrigation, water logged and furrow irrigation methods). The 4 to 12 replications were chosen in each site depending on its' size. Soil samples were collected in all replications from the 0‒10 and 10‒30 cm layers. Soil properties such as texture, organic matter, acidity, electrical conductivity, total soluble sodium, calcium and magnesium concentrations, and structural stability (dispersible clay) were measured for 94 collected soil samples. One-way ANOVA, Duncan's mean test and Principal Component Analysis were used to analyze and interpret the data. The results showed that wastewater affected some soil properties by leaching soluble salts into deeper soil horizons and also adding organic matter and some minerals into the soil. Electrical conductivities of the 0‒10 cm layer in control sites (no irrigation) and the 10‒30 cm layer in sites with furrow irrigation method were significantly greater than water-logged irrigated sites (α= 0.05). Applying wastewater increased soil organic matter content and aggregate stability significantly (α= 0.05). Irrigating the sites with wastewater decreased soluble sodium contents and dispersible clay of the soil surfaces; hence the soil structural stability was increased. Overall, applying wastewater to irrigate the planted seedlings in rangeland restoration projects has benefits as its use in these areas has lower environmental risk when compared with agricultural fields.
