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  • Reese posted an update 7 months, 2 weeks ago

    So the new control measures should focus on the urbanization regulation. In addition, the interactions between different socioeconomic factors are proved to bivariate enhance the influences on the PM2.5 concentration levels. Multiple factors should thus be taken into account when any new control policies are going to be established.This study aimed to investigate a mixed microalgae culture’s capacity to simultaneously remove nutrients and organic matter from industrial effluents while producing carbohydrate-rich biomass. A culture initially dominated by filamentous cyanobacteria Geitlerinema sp. was inoculated in a lab-scale stirred tank photobioreactor, operating at 10, 8, and 6 days hydraulic retention time (HRT). The results show that different HRT led to different inorganic carbon profiles and NP ratios in the culture, influencing microbial changes, and carbohydrate content. Hence, higher N-NH4+ removal efficiencies were obtained at HRT of 10 d and decreased with decreasing HRT. Whereas, complete depletion of P-PO43- was achieved only at HRT of 8 d and 6 d. Also, the highest COD removal efficiency (60%) was achieved at 6 d of HRT. The maximum accumulation of carbohydrates was achieved at HRT of 8 d, which presented an NP ratio of 221 and carbon availability, recording a constant carbohydrate content of 57% without any additional carbon source. Furthermore, this operational condition reached the best biomass production of 0.033 g L-1d-1 of easy-settling cyanobacteria dominated culture. According to the results, this process presents an alternative to recycling industrial effluents and, at the same time, grow valuable biomass, closing a loop for sustainable economy.Chlorella vulgaris (C. vulgaris) was promising microalgae to simultaneously achieve biomass production, carbon dioxide (CO2) fixation, nutrients removal and proteins production especially under different conditions of CO2 gas and wastewaters. Results presented that maximal specific growth rate of C. vulgaris was 0.21-0.35 d-1 and 0.33-0.43 d-1 at 0.038% and 10% CO2 respectively, and corresponding maximal CO2 fixation rate was attended with 4.51-14.26 and 56.26-85.72 mg CO2·L-1·d-1. C. vulgaris showed good wastewater removal efficiency of nitrogen and phosphorus at 10% CO2 with 96.12%-99.61% removal rates. Nitrogen fixation amount achieved 41.86 mg L-1 when the initial NH4Cl concentration was set at 60 mg L-1 at 10% CO2. Improved total protein (25.01-365.49 mg) and amino acids (24.56-196.44 mg) contents of C. vulgaris biomass was observed with the increasing of added CO2 and ammonium concentrations. Moreover, the developed kinetic function of C. vulgaris growth depends on both phosphorus quota and nitrogen quota with correlation coefficient (R2) ranged from 0.68 to 0.97. Computed maximal consumed nutrients concentrations (ΔCmax) based on Logistic function are positively related to initial NH4+-N concentrations, which indicated that adding ammonium could stimulate the utilization of both phosphorus and nitrogen.The Great East Japan Tsunami, triggered by the earthquake that occurred on March 11, 2011 in the Pacific Ocean, caused significant fatalities and socioeconomic damage. As recovery of a disaster area requires significant time, all possible mitigation measures must be prepared in advance for future events. As a tsunami countermeasure, coastal forests have been acknowledged to considerably reduce tsunami energy and decrease tsunami-related damage. In the Great East Japan tsunami, many trees of coastal forests were damaged by trunk breakage and overturning. This led to further infrastructural damage as the debris were transported landward and seaward by floodwaters. To better protect coastal areas from the secondary effects of tsunamis and reduce tsunami energy, coastal forests must exhibit higher resistance. This research investigated the effect of forestry management by applying different levels of thinning of trees as a means of resistance to tree damage under tsunami events. In October of 1999, study plots were established with different thinning intensities in a mature coastal forest of Pinus thunbergii trees. As a useful indicator of the resistance of coastal forests to tsunamis, the threshold tsunami velocities at which trees in these study plots begin to be destroyed were calculated using a mechanistic model. The results revealed that trunk diameter is the most important parameter for increasing resistance to tsunamis. An analysis of the generalized linear model for diameter growth showed that heavy thinning best enhanced the diameter growth. Therefore, heavy thinning is the most effective approach to increasing the resistance of trees to tsunamis. Considering the relationship between resistance to tsunami and inundation depth, the resistance to tsunami decreased rapidly with increasing inundation depth in all plots. SGI-1776 solubility dmso Differences in the resistance to the tsunami were not observed across all plots when the inundation depth exceeded the mean tree height.Local species assemblages are likely the result of habitat and landscape filtering. However, there is still limited knowledge on how landscape functional connectivity complements habitat attributes in mediating local species assemblages in real-world fragmented landscapes. In this study, we set up a non-manipulative experimental design in a standard production forest to demonstrate how functional connectivity determines the spatial distribution of a bird community. We test single- and multispecies spatially explicit, landscape functional connectivity models framed within the circuit theory, considering also patch attributes describing habitat size and quality, to weight their effects on species occurrence and community assemblage. We found that single-species functional connectivity effects contributed positively for occurrence of each species. However, they rarely provided competing alternatives in predicting community parameters when compared to multispecies connectivity models. Incorporating multispecies connectivity showed more consistent effects for all community parameters, than single-species models, since the overlap between species’ dispersal abilities in the landscape shows poor agreement. Habitat size and quality, though less important, were also determinant in explaining community parameters while possibly relating to the provision of suitable nesting and foraging conditions. Both habitat and landscape filters concur to govern community assembly, though likely influencing different processes while landscape connectivity determines which species can reach a patch, habitat quality determines which species settle in the patch. Our results also suggest that surrogating multispecies connectivity from single species has potential to source bias by assuming species perceive landscape and its barriers similarly. Inference on this issue must be gathered from as much species as possible.

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