Showing 3 results for Richness
Mehdi Heydari, Ali Mahdavi,
Volume 1, Issue 1 (9-2014)
Abstract
Despite the implementation of watershed management projects over a wide area has long history in Iran, but the quantitative assessment of these projects have been neglected. In this study, the effects of watershed management project of Kalan-e-Eyvan in Ilam province from ecological point of view (the relation of vegetation composition with physicochemical soil properties) were investigated. In doing so, four status of watersheds were assessed, namely, status A (implemented area after 5 years in 2010), status B (the witness area without implementation of plan in 2005), status C (the witness area without implementation of plan in 2010) and status D (the area A before implementation of the project in 2005). The results showed that plant species in four statuses were classified into two groups based upon Canonical Correspondence Analysis (CCA) and the species in A, B and C statuses were mostly perennial classified as climax stage species. The results showed a floristic similarity between planed and control areas after 5 yearsturned out. There werea clear differences regarding to vegetation composition, nutrient and saturation percentage (SP) between the area after and before plan implementation. The results of one-way ANOVA indicated significant differences regarding to diversity and richness between four statuses. The results of Duncan-Test showed that the implementation of watershed management project has caused increasing in diversity and richness in planned areas in comparison with non-planned watershed management ones.
Kobra Sabzi, Ehsan Sayad, Hamid Taleshi, Reza Basiri,
Volume 1, Issue 1 (9-2014)
Abstract
In forest ecosystems espcially riparian ones, individual trees have important effects on soil macrofauna. This research was conducted to study the effect of Populuseuphratica on soil macrofauna in Karoon River Side Forest near Shooshtar. Soil macrofauna were sampled in November 2012. Soil macrofauna under tree crown (in three crown diameter category) on parallel transects with 100 m distance from the river and eachother was sampled. Soil macrofauna in 50 cm× 50 cm plots upto 10 cm depth were hand sorted and identified to family level. Totally 342 plots were sampled. The results of correlation showed that there were negetive relationship between distance to tree crown center and soil macrofauna and this relationship was higher in the case of trees with lager crown. The results of ANOVA also showed that the crown diameter size did not have significant effect on soil macrofauna except on soil macrofauna evenness with low significant level. The correlation of distance to river with soil macrofauna showed higher abondance, richness and diversity in farther distances to the river while evenness were higher near the river. Totally it should be saied that indvidual P. euphratica wereeffective on soil macrofauna and it also should be considered the distance from riverside had massive influence on crown diamere.
Shaieste Gholami, Ehsan Sayad, Hanie Shahghobadi,
Volume 1, Issue 2 (3-2015)
Abstract
One of the main factors affecting sustainable management in the forest ecosystem is the biodiversity conservation. For achieving this purpose, we need to estimate and determine the biodiversity. The efficiency of sampling depends to some extent on plot size in a study. Therefore, a study was conducted in the Zagros forest (Baniloan, Javanrood, Kermanshah) to assess the effect of plot size on the abundance and diversity of tree species. We measured the diversity indices e.g. (Shannon H), richness (Minhinick) and evenness (Sheldon) in our data. These indices were analyzed at 270 sampling points along 3 parallel transects which ran perpendicular to the slope. The distances between transects was 500 m. Each transect comprised 30 sampling points with 3 different sizes of plots (10m×10m-20m×20m and 30m×30m plots). Abundance and diversity of tree species, richness and evenness analyzed by ANOVA and Duncan. The results showed that abundance and diversity increased significantly by increasing the size of the plots. The maximum diversity was seen in 900m2 plot size. At 400 m2 plot, richness was higher than two other plot size. But evenness was not significantly affected by plot size.
