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Many countries have implemented policies to reduce the negative effects of deforestation. In Iran, the Zagros Forest Preservation Plan (ZFPP) began in 2003. This study evaluates the effectiveness of ZFPP on land cover changes in two periods, before (1993–2002) and after (2002–2017) implementation of the plan. Logistic regression (LR) analysis was used to examine the effectiveness of key socio-economic, environmental and demographic drivers associated with deforestation activities. The results showed that despite the implementation of ZFPP forest conversion to other land-use types increased during the second period compared to the first. Calculating the annual rate of deforestation showed that this rate increased from -0.4% to -0.5%. The results of LR showed that the occurrence of deforestation in different years was significantly related to distance from rivers, croplands, cities, roads, and slope such that areas with low slope and close to these features have a high probability of deforestation activities.

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Intrinsic rates of population increase (r) were evaluated as a measure of population dynamics of four strains of Brachionus plicatilis and two strains of B. urceolaris from Iran in response to different salinities and feeding algae. Each rotifer strain was cultured at four salinities: 5, 20, 25 and 30‰ and fed with two microalgal species: Chlorella vulgaris and Nannochloropsis oculata. Salinity of 5‰ was critical for all the examined strains, at which r was at minimum and was different from the other salinities (P < 0.05). For B. plicatilis strains, the maximum r was observed in those fed on Chlorella at salinities of 10 and 30‰ (64 ± 0.01 day −1). While, in B. urceolaris, maximum r was for Nannochloropsis fed rotifers at salinity of 20‰ (0.69 ± 0.01 day −1). Maximum final population density (FD) was obtained for a strain of B. urceolaris fed on Nannochloropsis at 20‰ (329.3 ± 10.9 ind.mL −1). FD was relatively lower in B. plicatilis strains among all examined salinities. ANOVA showed the significant effect of salinity and rotifer strain, and algae × rotifer strain on both r and FD, and salinity × rotifer × algae on FD (P < 0.05). IntroductionRotifers are considered as ideal model organisms for various kinds of biological laboratory studies including population dynamics (YOSHINAGA et al., 1999;SARMA, 2006;SNELL and DESROSIERS, 2008). They have also become a valuable and, in many cases, indispensable food organism for first feeding of a large variety of cultured marine finfish and crustacean larvae (DOUILLET, 2000).Success in rotifer culture seems, to a great extent, to be dependent on providing adequate information on the life history characteristics and environmental preferences of each biotype. An increasing number of studies have been carried out on the effects of salinity, temperature and the type and concentration of food on the demographic traits and population growth of rotifers (CABRERA et al., 1993;OLTRA and TODOLI, 1997;FIELDER et al., 2000;SARMA and NANDINI, 2002;ATHIBAI and SANOAMUANG, 2008). These studies were accomplished using several rotifer species (XI et al., 2001;SUCHAR and CHIGBU, 2006;WULLUR et al., 2009