the aim of this study was to develop an optimal sustainable forest plantation based on goal programming and analytic hierarchy process (ahp) methods. this study was carried out in guilan province, north of iran. first of all, the ecological capability of the study area for plantation establishment/maintenance was evaluated based on multi-factor method and specific ecological makhdoum model by m...

the length-weight relationships for three fish species from beheshtabad river, karun river drainage (western chaharmahal and bakhtiari provinces, iran) were investigated. the values of the slope parameter ( b ) in the length-weight relationship equations were determined as 2.79 for capoeta damascina , 3.10 for chondrostoma regium and 3.09 for oncorhynchus mykiss , all of which were significantl...

Nurse crops of widely spaced pioneer trees are a silvicultural approach to protect the regeneration of frost sensitive target tree species. If overstorey nurse crops are harvested, they can provide additional short-term benefits through increased biomass production, e.g., for bioenergy. However, the intensification of biomass exports from forests might impact negatively on ecosystem nutrient po...

Investigations in the past two decades have shown the utility of the Newtonian model of heat loss from homoiotherms which was established in the biological literature by Scholander et al. (1950a, b, c). The stimulative effect of those papers is seen in a proliferation of thermoregulatory studies (for reviews see Bartholomew, 1968; Dawson & Hudson, 1970). Sufficient data'have been generated from...

The allometric equations developed by Whittaker et al. (1974) at the Hubbard Brook Experimental Forest have been used to estimate biomass and productivity in northern hardwood forest systems for over three decades. Few other species-specific allometric estimates of belowground biomass are available, because of the difficulty of collecting the data, and such equations are rarely validated. Using...

Surface lignite coal mines in east Texas are commonly reforested using loblolly pine (Pinus taeda L.) following mining and reclamation activities. Due to the nature of such an extreme disturbance, altered growth patterns, growth rates, and productivity could be expected. We destructively sampled aboveand belowground tissue to develop prediction equations specific to these sites. These predictio...

The traditional method for normalizing quantitative strength data is to divide force or torque by body mass. We have previously shown that this method is not appropriate for able-bodied children and young adults and that normalization using allometric scaling is more effective. The purpose of the current study was to evaluate the effectiveness of applying existing normalization equations for lo...

Nutrient budgets for forested ecosystems have rarely included error analysis, in spite of the importance of uncertainty to interpretation and extrapolation of the results. Uncertainty derives from natural spatial and temporal variation and also from knowledge uncertainty in measurement and models. For example, when estimating forest biomass, researchers commonly report sampling uncertainty but ...