Forest conservation mediating soil quality relationship with diversity of various plant layers in the biosphere of Arasabran, Iran.

The link between biodiversity and ecosystem multi-functionality is an ongoing concern in ecological studies. Ecologists have focused on soil quality (SQ) as an ecosystem function and its relationship to biodiversity. Developing an appropriate and sensitive soil quality index (SQI) is critical, but it is severely restricted particularly in the forests. This study determined the most appropriate SQI for both protected and unprotected areas of Arasbaran biosphere reserve forests (Northwest Iran), as well as its relationship to the diversity of three layers of forest plant species (tree, tree regeneration, and forest floor plant cover), NDVI index, and litter amount. Three approaches were utilized to establish SQI for two types of soil data sets, including total data set (TDS) (pH, EC, SP. OC, caco3, clay, silt, sand, N, P, K, BD, gravel, C·N) and the minimum data sets (MDS) (SP. OC, clay, silt, N, K, BD, C·N): (1) SQI-1 (simple additive), (2) SQI-2 (Nemero quality index), and (3) SQI-3 (weighted additive modeled). Three SQI strategies were assessed using three different methods: Overall Sensitivity Index, Efficiency Index and Sensitivity Index. The findings revealed that the SQI-3 is the best SQI for employing only a limited number of soil properties (MDS). The findings revealed that the SQI-3 has a positive and significant relationship with the Evenness-tree and Taxa-Regeneration in the protected region (P-Value: 0.02). In contrast, the SQI-3 has a negative correlation with the NDVI (Normalized Difference vegetation Index) (P-Value: 0.02) but a positive significant relationship with the litter and Taxa-Grass indicators in the unprotected region (P-Value: 0.00). The study's findings demonstrated that forest preservation affected the link between the SQI and the studied parameters. As a result, it is concluded that biodiversity-ecosystem function is impacted by management changes and cannot be maintained constant under varied management conditions. This shift in the links between plant and SQ emphasizes the fact that plants biodiversity loss and SQ can have particularly severe consequences in non-protective conditions, necessitating biodiversity conservation measures to mitigate the effects of conservation.

Evaluation of hackberry (Celtis australis L.) fruits as sources of bioactive compounds.

Hackberry (Celtis australis L.) is native to the Mediterranean region and is distributed in Europe, Turkey, North Africa, and Iran. To the best of our knowledge, no study has been conducted on C. australis L. in the Arasbaran region, Iran. In the present study, total phenol (TP), flavonoid (TF), antioxidant capacity based on DPPH and FRAP assays and phenolic compounds and sugars profiles were investigated. According to the results, the range of antioxidant capacity based on DPPH and FRAP assays was 14.12-88.24% and 44.35-117.87 mg Fe2+/100 g, respectively. Also, the range of gallic acid, caffeic acid, chlorogenic acid, rutin, p-coumaric acid, rosmaric acid, cinnamic acid, and apigenin content was 2.59-26.32, 2.03-9.32, 0.94-11.35, 1.80-4.857, 2.32-9.52, 4.74-51.38, 0.18-2.10 and 0.27-1.37 mg/g, respectively. The results of factor analysis showed that the C12, C14, C15, C20, C8, C16, C3, and C20 genotypes are positively characterized by the first principal component (PCA1) that have a higher caffeic acid, chlorogenic acid, rutin, p-coumaric acid, rosmaric acid, quercetin, cinnamic acid, and apigenin phenolic compounds. Based on cluster analysis, the twenty genotypes were located in 2 main clusters. In general, the obtained results can be useful for breeding programs and the introduction of cultivars in Celtis australis L.

Toward the identification of molecular markers associated with phytochemical traits in the Iranian sumac (Rhus coriaria L.) population.

Sumac (Rhus coriaria L.) is one of the important forest species dispersed in the northwest of Iran. It is one of the important spice in Iran and the Middle East because of active components containing organic acids, phenolic acids, flavonoids, anthocyanins, tannins and terpenoids. This study aimed to investigate population structure and linkage disequilibrium (LD) extent within Rhus coriaria L. genotypes using ISSR markers and identify molecular markers associated with phytochemical traits using association analysis. In the molecular part of the experiment, the genetic diversity of 75 sumac genotypes from five different areas of northwest Iran was assessed by 18 ISSR primers. In the phenotypic assessment, the fruits of the sumac genotypes were analyzed using HPLC-LC/MSMS for determining phytochemical components including maleic acid, ellagic acid, maleic acid hexoside, gallic acid, coumaric acid, quercetin, caftaric acid, and linoleic acid. The phenotypic data analysis revealed the great phenotypic diversity among and within Iranian sumac populations for the studied phytochemical traits. The studied sumac genotypes were divided into two subpopulations based on molecular marker-based structure analysis. A significant level of LD was observed in 11.64% of the ISSR marker pairs (p < .05). The mixed linear model procedure showed that 12 loci had a significant association with investigated traits. The ISSR loci identified in this study can be potentially used in marker-assisted selection in sumac breeding programs.

Economic sustainability assessment in semi-steppe rangelands.

This study was conducted to determine indices and components of economic sustainability assessment in the pastoral units of Sahand summer rangelands. The method was based on descriptive-analytical survey (experts and researchers) with questionnaires. Analysis of variance showed that the mean values of economic components are significantly different from each other and the efficiency component has the highest mean value (0.57). The analysis of rangeland pastoral units with the technique for order-preference by similarity to ideal solution (TOPSIS) indicated that from an economic sustainability standpoint, Garehgol (Ci = 0.519) and Badir Khan (Ci = 0.129), pastoral units ranked first and last, respectively. This study provides a clear understanding of existing resources and opportunities for policy makers that is crucial to approach economic sustainable development. Accordingly, this study can help better define sustainable development goals and monitor the progress of achieving them.

Studying the results of two methods of harvesting after a period of forest management plan.

To study the results of interference of strip cutting and single selection systems during the performance of the plan (1993-2003) in the Janbe Sara district, raw data which was collected during two years were compared together. Inventory was done in systematic random way and intensity of 3.3% in both years. In this research parameters like average diameter of basal area mean (in breast height), volume mean and density in ha, diameter distribution, regeneration situation and qualitative class of trees were studied. Totally this study's results showed that although the diameter distribution curve in 2003 was getting close to the normal curve, as compared with 1993, but was still for from it in district. Also against the reduction of volume mean in ha, diameter of basal area mean and the percentage of trees in high qualitative classes in both methods were reduced, we should point that, this reduction in single selection parcels is less than strip cutting parcels. Results of studying the density in ha of trees and regeneration show the equal increasing process in both groups of parcels (single selection and strip cutting). Generally according to failure of the plan, with comparing both methods, we can conclude that we can get better results of single selection rather than strip cutting. Meanwhile considering 68% strip cutting harvest of the district the majority of strip cutting is affecting the failure of the plan.

Investigation and comparison of natural regeneration structure of forest stands in protected and non-protected areas in Arasbaran.

In this study, a part of Arasbaran forest stands in two protected and non-protected areas have been compared for quantitative and qualitative factors of regeneration. Thus, using aerial photographs of 1967 in the scale of 1:20000, the similarity of these stands was examined and the comparable stands were chosen. Afterward, 77 circle plots of 0.01 ha in protected area and in the same way 77 circle plots of 0.01 ha in non-protected area with a grid size of 250x250 m were established. In each plot, all species with diameter at breast height (dbh) from zero to 7.5 cm were measured. According to the results the number of regeneration average in protected area was significantly higher than that in non-protected area. Oak and Hornbeam regeneration percentages showed highest significant difference in the selected areas. Additionally, these two species have the highest mixture percentage. The regeneration structure in both areas includes high and coppice systems, but coppice is prevalent. In both regions cutting, branching and grazing are the most important destructive factors, and the effects of these factors are higher in non-protected area.