Journal of Renewable Natural Resources Research
Year:2015 | Volume:6 | Issue:2 (SERIAL NUMBER 20)|Papers Count:6

Increase in greenhouse gases causes climate change and global warming and has been adverse effects on the earth. The aim of this study is to survey the effects of afforestation on soil carbon sequestration. This Project was done as completely randomized design in a factorial experiment in Robinia-Fraxinus, Robinia and Cupressus stands with the surrounding arid lands (control). The study was done at Forest Pardisan Park in Tehran and it measured the amount of carbon sequestration in soil. It also investigated relationship between physical and chemicals oil factors and with soil organic carbon. The results show carbon sequestration is the highest significant value (p<0.01) in Robinia-Fraxinus stand soil (18.96 ton per ha). Also, carbon sequestration in Robinia and Cupressus is (14.86 and 9.69 ton per ha) and barren land (6/97 ton per ha) respectively. The economic value of carbon sequestration was calculated for these species, 3792, 2972 and 1938 dollars respectively. Organic carbon in 0-15 cm soil depth of afforest stand more than 15-30 cm depth but was observed reverse in the arid lands. Also stepwise regression showed that clay and nitrogen are the most important components affecting soil organic carbon. Generally the process of carbon sequestration leads to improvement of soil and water quality; it improves soil hydrology, prevents erosion and reduces the loss of nutrients. Thus, the optimal management of ecosystems should increase the potential of soil carbon sequestration.

Beech (Fagusorientalis L.) is a wood species from genera of deciduous and hardwood trees. It has been one of the most important industrial wood species in Iran which belongs to the non- durable wood species class.In order to evaluate the wood extractives role on little durability of this wood species against white- rot, Trametes versicolor fungus, wood extractives of wood samples in dimension of 2×2×2 cm were soxhlet (?!) extracted with various combinations of organic solvents including n- hexane: ethanol (1: 1), ethanol, chloroform, diethyl ether, and water, according to TAPPI T204 om- 88 and ASTM 1107- 96. Average percentage of chloroform wood extractives of beech wood equal 5.97% was determined. Results from weight loss of specimens after 14 weeks duration indicated that the effect of chloroform extracts was more on durability of specimens against wood- rotting fungus and weight loss of specimens (30.38%) was higher than the other treatments. Finally, phenolic and lipophilic compounds in the chloroform extractives of this wood species were identified by GC/MS. Generally, 28 compounds were identified with different percentages in the beech wood. The most abundant compounds identified were hexadecanoic acid, trimethylsilyl ester (13.28%), trans- Caryophyllene (12.88%), trimethylsilyl 3, 5- dimethoxy- 4- (trimethylsilyloxy) benzoate (11.69%), eicosane (6.96%), and hexadecane (6.79%). Also, from phenolic compounds (sesquiterpenes) with antifungal, antibacterial, and larvicidal activity, trans- Caryophyllene (12.88%), beta.- Selinene (3.10%), beta.- Bisabolene (3.01%), .alpha.- Selinene (2.19%), .alpha.-Caryophyllene (1.85%), Caryophyllene oxide (1.54%), alpha- Copaene (0.92%), delta.- Cadinene (0.85%), beta.- Elemene (0.77%), and isoeugenol (0.19%) were identified.

This study was conducted to determine the fiber morphological characteristics of Eggplant stalk’s tissue (Solanummelogena var. esculentum) cultivated in the west region of Ghuilan province (Astara region). For this purpose, 20 stalks of Eggplant were collected from Astara region gardens and 3 stalks were randomly selected from among these stalks. After the fibers separation by Franklin method (1954), fiber dimensions, fiber biometric coefficients and weight percentage of stalk components including bark, core and pits. The results showed no significant difference in fiber dimensions and fiber biometric coefficients between different heights of stalks. Besides, there was no significant difference in percentage of core and percentage of bark at different heights of stalks, while a significant difference was found between percentage of pit at different heights of stalks (p<0.05), showing a decrease in stalks by increasing heights of stalks the pit. The averages of fiber length, fiber diameter, lumen diameter and cell wall thickness for this species were 0.63 mm, 16.23mm, 7.99 mm, 4.12 mm, respectively. Also, the average of runkel, flexibility and felting Coefficients were calculated as 51, 49 and 40.27, respectively. The weight percentage average of stalk components, including bark, core and pit, from top to the down of stalks were also estimated to be 4.84%, 14.62% and 80.54%, respectively.

In this study, the effects of fish waste powder addition and the coupling agent Maleic Anhydride Poly Ethylene (MAPE) content on notched impact strength and physical properties of wood-plastic composite were studied. Wood flour (40%) was mixed with 60% of polyethylene (PE). Fish waste in three levels of 5, 10 and 15% was mixed into wood powder and coupling agent on three levels (0, 2 and 4) of PE in a domestic blender at 180 oC and a speed of 60 rpm. Standard composite samples were manufactured using injection molding. Notched impact strength and physical properties including water absorption and thickness swelling were measured. The results revealed that with a 15% increase in fish powder waste, the highest impact strength was gained along the lowest water absorption and thickness swelling. The increase in coupling agent concluded in impact strength and physical properties enhancement up to 4%.

Evaluation of soil quality has great deal of importance in clarification of impacts of land use types and management in rangeland landscapes. Vegetation composition is affected by wide varieties of edaphically factors, in turn accompany with other management approaches leading to specific vegetation dominance. For this, two grassland and shrub lands habitats were selected in Shahindej rangelands. Soils factors measurement was carried out in three depths 15-30 and 30-60 cm including P, C, K, N, EC, pH and percentages of lime, moisture, and silt ad clay contents. To separate means and data analysis T-test and software SPSS were used respectively. Results showed that under shrub lands sites, EC, moisture and clay percent's differed significantly at probability of 5%. There was no any significant difference between all soils factors for grassland. Grassland and shrub lands communities varied at 0-15 cm in percentages of lime, EC, sand and clay contents and EC, lime and clay percent showed significant difference in 15-30 and 30-60 cm, however this was not the case for other parameters. Finally, it can be included that all soils factors do not affect vegetation communities to the same degree. Through correct management, conversion of grassland to shrub lands can be prevented while taking edaphically properties in rangeland restoration plans and selecting suitable species according to ecological conditions. Having some knowledge on edaphically factors in plant ecology seems to be essential since it is a primary factor to determine vegetation type.

Range land Suitability is one of the most important factors in rangeland inventory and monitoring. Factors effecting on range suitability should be taken into consideration. All parts of range land ecosystem effect on range suitability; however, investigation on all factors is impossible. So‚ physical and vegetation factors for creating three sub models including yield‚ water sources and erodibility were considered. Because of high quality of vegetation‚ soil‚ climate and quantity of water and increasing range land degradation‚ this research has been done in Tornas area of Eghlid in Fars province using F.A.O. (1991) manual and (GIS). In general‚ slope‚ range types elevation source‚ water point distribution‚ natural limits more than vegetative factors effect on Tornas rangeland suitability. So‚ final results showed that rangeland with 36.9 (1436.7520ha) S1‚ 24.2 (874.2261ha) S2‚ 23.5 (849.0556ha) S3 and 12.7 (459.4202ha) are not suitable for sheep grazing.