Gholam Ali Heshmati; vahid karimian
Abstract
To apply scientific and proper management of rangeland ecosystems, having information on health and functions indices of ecosystem is required. Using landscape function analysis, the present study deals with assessing and comparing of ecological indices in northern and southern landscapes, Darehkonari ...
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To apply scientific and proper management of rangeland ecosystems, having information on health and functions indices of ecosystem is required. Using landscape function analysis, the present study deals with assessing and comparing of ecological indices in northern and southern landscapes, Darehkonari Khashab of Gachsaran. Length and width for ecological patches in northern landscapes in species Astragalus fasciculifolius Boiss, Centaurea intricanta Boiss, Cousinia multiloba DC, and inter patches(bare and litter), in southern ones on species Cousinia multiloba DC, Stachys byzantina C. Koch, Stachys byzantina C. Koch and Cousinia multiloba DC and inter patches were recorded along three 50 m transects across both southern and northern aspects. In addition, eleven soil surface indices were measured. These indices belong to three main characteristics of soil stability, infiltration and nutrient cycling. The results showed that the indices of stability and nutrient cycling in both landscapes have a significant difference (p <0.05), but this was not case for infiltration index (p>0.05). The main ecological indicator of northern and southern landscapes are C. intricanta and S. byzantine + C. multiloba, respectively.
mohsen padyab; Sadat Feiznia; Hasan Ahmadi; Ardeshir Shafei
Abstract
Evaluation of changes present in soil and water resources due to operation implement of floodwater spreading is necessary to assess their positive or negative resultant effect. Rate of the internal sediment to diversion spreader channels, surface sedimentation and aggregation of the spreading field depth ...
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Evaluation of changes present in soil and water resources due to operation implement of floodwater spreading is necessary to assess their positive or negative resultant effect. Rate of the internal sediment to diversion spreader channels, surface sedimentation and aggregation of the spreading field depth are most important effective attributes on the yield of floodwater spreading systems. These factors can change physical and chemical properties of studied field, as, by measuring of the infiltrate depth sedimentation of can achieve influencing depth of floodwater. To determine the effect of flooding spread on the sediment infiltrate rate in the field depth of Gachsaran floodwater spreading, from 0-15, 30-15, 30-45 and 45-60cm of the soil surface of spreading field and control were sampled. Granulometry of all samples was done using dry sieve and hydrometric analysis and then percent of the sediment grains with size of less than two millimeters were subjected to analysis of variance (ANOVA) by Duncan t-student test for 80 sampled samples. Results showed that deep entering of the sediments into drilled profiles to 30-45cm was completely distinct which can affect on the soil physical and mechanical properties. However, after the 30-45cm depth, the impact of floodwater spreading was minimal. The infiltration of each studied layer is the most important feature which will change from surface to the depth of spreading belts, so that by increasing infiltrated fine particles in the depth and blocking pores, the soil layers are clogged and in result reduce the infiltration rate, sharply. This state was more remarkable in the spreader belts surface. Furthermore, by depositing the sediments in the surface (0-15cm depth), an impermeable and earthen layer is created which prevent from infiltrate the particles and even water into soil depth. Generally, with determine of the deposited sediment level in the spreading belts and also its deep infiltrate rate can provide effective and practical decision to improve efficiency and easy maintenance of the floodwater spreading systems or even not use this method.
H. Saidian; H. R. Moradi; F. Tarnian
Volume 63, Issue 1 , June 2010, , Pages 1-12
Abstract
Using of different systems of soil plough after changing unconsciously and non-scientific of land use, other soil physical and chemical characteristics affected. This fact, especially in marginal lands and mountainous regions is more visible. This research compared with the purpose of studying land use ...
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Using of different systems of soil plough after changing unconsciously and non-scientific of land use, other soil physical and chemical characteristics affected. This fact, especially in marginal lands and mountainous regions is more visible. This research compared with the purpose of studying land use changing on some soil physical and chemical characters like very tiny sand percent, pH, Ec, clay percent, sand percent, silt percent, soil moisture, calcium carbonate in Gachsaran and Aaghajari formation. So that in aghajari formation 7 points and with 3 replicates and in gachsaran formation 6 points and with replicates in three land uses range, residential and agricultural land uses sampling of soil was done. Sampling of the depth 0-20 cm soil was done. After tests implement are concerned, the results were investigated. According to the results, range land in two Aghajari and Gachsaran formations in terms of clay percent, sand, EC, pH, moisture and Calcium Carbonate a meaningful difference have, and in other cases was not seen any disagreement. between agriculture land use in two Aghajari and Gachsaran formations in terms of very tiny sand percent, sand, clay, moisture and calcium carbonate meaningful difference have, and in other cases was not seen any disagreement. In residential land use in two Gachsaran and Aghajari formations only in clay percent and EC, there are a meaningful difference, and in other cases was not seen any disagreement. In each formation also land uses had effective role in soil physical and chemical characteristics.
