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Direct measurement of aboveground biomass of trees is considered as one of the labor-intensive, expensive, time consuming and destructive tasks. The objective of this study was to estimate the biomass of four coniferous and deciduous trees species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia and Morus alba) by means of high resolution Quickbird remotely-sensed data of over a plantation are established around the industrial domain of Isfahan’s Mobarakeh Steel Company. To this aim, three approaches based on vegetation indices, texture analysis and Principal Component Analysis (PCA) were applied to extract required information from satellite imagery. The correlation analysis between field-assessed biomass and the image-based information and regression models were built. The results using vegetation indices (DVI and NDVI) for coniferous species as well as athose from texture analysis and PCA for deciduous species showed significant corelations. As depicted by the species-specific regression of biomass revealed the amount of RMSE ​​ for P. eldarica, C. arizonica, R. pseudoacacia and M. alba to be 53, 20, 30 and 50, respectively. Moreover, species-specific biases for P. eldarica, C. arizonica, R. pseudoacacia and M. alba was shown to be 30, 10, -30 and 44 respectively. The results of this study supports the use of the applied Quickbird data for model-based estimation of aboveground biomass across the study site.

Introduction: Identification of degrading microorganisms of toxic materials is regarded as an important step to complete air treatment systems. Effective microorganisms in treatment and elimination of pollutants seems to be different depending on the type of pollutants as well as environmental conditions. Identification of these microorganisms can determine optimum conditions for the system performance and the maximum efficiency can be reached. Moreover, biotechnological methods can strengthen the microorganisms to treat the pollutants. This study aimed to identify the predominant microorganisms at two biotrickiling filters that formaldehyde was used in one and ethanol in another as the sole carbon source. Methods: In this study, two biotrickling filter pilots were made at the laboratory scale. These microorganisms were inoculated and adapted within three months. Then biotrickling filters were studies for a long time. At the end of experiments, biofilm samples were taken from biotrickling filters and predominant microorganisms were identified via microbiology studies. Results: The results of the present study managed to identify such microorganisms as Salmonella Bongori, Pneumonia, Subspecies Pneumonia, Klebsiella Terrigena, etc. at different parts of both biotrickling filters. Conclusion: Microbial species can be widely changed with operating of biotrickling filters at different conditions. Identifying active microorganisms in each biotrickling filter can lead to detecting optimum conditions as well as the risks caused by transfer of the filters' available microorganisms to the human body .

Climate change, in addition to increasing temperature, causes changes in the duration, intensity, form, and timing of rainfall in different parts of the Earth, which can cause droughts and floods. It also changes the volume, duration, and runoff duration, which will bring about many developments and changes in the water-resource management (Kamal and Massah Bavani, 2009). In order to reduce inconsistencies, studying the impacts of climate change on water resources is necessary. One of the most widely used models for these future studies is Atmosphere-ocean General Circulation Models (AOGCMs) (Wilby and Harris, 2006). In general, most studies present a high degree of uncertainty as a result of using AOGCMs in the simulation of climate change and hydrology parameters. the outputs of simulated water-resource models under climate change could be relied on when the uncertainties are taken into account at all stages (Semenov and Stratonovitch, 2010). In order to innovate the research method, in this study 10 AOGCMs under three greenhouse gas emission scenarios (A1B, A2, and B1) were used in the simulated range of hydro-climatic variables through climatic models and downscaling methods in the Dez Oliya basin during 2040-2069. In Summary, when reviewing the range of hydro-climatic variable changes in the future period, it could be observed that the uncertainty of AOGCMs under all three emission scenarios is greater than the downscaling methods.

Hydraulic jump is one of the important phenomena in rapidly varied flow. Due to this phenomenon the energy loss, the upstream flow velocity significantly decreases. In the present study, hydraulic jump on a new roughened bed -with half cylindrical shape bars with three heights (r) and four different longitudinal spacing (s=1D, 2D, 3D, 4D) were investigated. In total 238 experiments were performed for a range of Froude numbers from 4.6 to 7.4 on horizontal bed and two adverse slopes of 1 and 1.5 %. The results showed that the sequent depth decreases and energy loss and bed shear stress increases as the height, spacing of the rough bars, adverse slope and Froude number increased. In hydraulic jump on adverse slope of 1.5% and rough bed with half cylindrical roughness, sequent depth 36% decreases and the bed shear stress coefficient is 16 times of its corresponding values on smooth and horizontal bed. Some empirical relations for sequent depth ratio, relative energy loss and bed shear stress coefficient were introduced. Totally, the results obtained show that, rough bed with adverse slopes may be used to achieve better performance in stilling basins.

This study was carried out to understand the dynamics of Lebanon oak coppice regeneration. In this regard, the effect of thinning on both individual sprouts and stools as well as estimation of sprout biomass using allometric equation were investigated. 45 Lebanon oak trees with different sizes (i.e. DBH from 25 to 65< cm) in five sites were cut and individual stumps were fenced to monitor the sprouting behavior. In the second year after the cutting, light (six sprouts reserved in each stool) and heavy thinning (three sprouts reserved in each stool) were conducted in two third of stools equally and the rest un-thinned ones were considered as control. Data analysis, five years after thinning, showed that the most portion of individual biomass allocated to main stem (57.4%), main branches, leafs and fine branches, respectively. On average 42% of total fresh mass of sprouts were reduced due to water loss in drying process. Analysis of variance indicated that stump size has no significant effect on biomass of individual sprout either stools while it was significantly different among sites. Comparison of thinning treatments and control one showed that light thinning resulted in sprouts with the most biomass while no significant difference was observed between heavy thinning and un-thinned. Using a basic power model, allometric equation was fitted to estimate the sprout biomass. Based on regression analysis as well as derived indicators (R2, STDEV, RMSE, rRMSE and nRMSE) and models validation by leave one-out method, the collar diameter was found as the best explanatory variable in young sprouts biomass.

Along with the numerous developments and facilities for constructing large dams, there is a need for developing design and construction methods for systems that can correctly discharge the floods. Weirs refer to any barrier across a channel that raises the flow level and accelerates the flow when flowing over it (Abrishami and Hoseini, 2011). Piano key weirs are the newest type of long-crest weirs and one of the best solutions for modifying the existing weirs. Reducing the energy of the flow over the weirs before their transfer downstream is a solution for preventing possible damage to the structure itself and downstream structures as well as the excess costs incurred by the builders of hydraulic structures due to constructing strong protective structures (Katourani, 2012). Lempèrière and Ouamane (2003) described the piano key weirs and stated their advantages compared to other conventional nonlinear weirs as the ability to place the weir in the crest of the reservoir dam and thus increasing the specific flow rate. Erpicum and Machieles (2011) compared the energy dissipation between two different geometries for a piano key weir and a spillway weir. Concerning the application of a block, the tests and results obtained by the US Land Renewal Organization indicate that using large blocks that separate the flow jet and create turbulence can effectively dissipate the kinetic energy of the current.

In the present study, CanESM2 climate change model and stormwater management model (SWMM) were employed to investigate the climate change effects on the quantity and quality of urban runoff in a part of Karaj watershed, Alborz Province. The base period (1985-2005) and future period (2020-2040) are considered for this purpose. Based on the existing main and lateral drainage system and to be more accurate, the watershed was divided into 37 sub-watersheds by ArcGIS software. To simulate rainfall-runoff, the intensity-duration-frequency (IDF) curve has been prepared for a 2-hour duration and 10-year return period, for the base period and RCP2.6 and RCP8.5 climate change scenarios based on the obtained precipitation data from Karaj synoptic station. Results showed that mean 24-hour precipitation values in RCP2.6 and RCP8.5 scenarios will increase by 21% and 11%, respectively, and maximum 24-hour precipitation values will decrease by 17% and 23%, respectively, as compared to the observed values in the base period. Also, based on the results of quantitative and qualitative runoff modeling in the study watershed, and according to the outflow hydrograph in the RCP2.6 and RCP8.5 scenarios, the outlet runoff discharge will decrease by 5.8% and 7.1%, respectively. Also, the flooded areas in the watershed will decrease by 13% and 15.28%, respectively. The concentration of pollutants in the RCP2.6 and RCP8.5 scenarios, compared to the base period, including total suspended solids (TSS), will increase by 7.48% and 9.24%, total nitrogen (TN) will increase by 6.93% and 8.48%, and lead (Pb) will increase by 7.32% and 8.91%, respectively.