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981.
Journal of Material Cycles and Waste Management - A spontaneous combination of hygienic in situ compatibilized polybutylene succinate/polylactic acids (PBS/PLA) was formulated through the addition...  相似文献   
982.
983.
The world has become dependent on petroleum as a feedstock for most products that we use in our daily lives. As an alternative, bio-refineries that transform biomass into biofuels and primary chemicals are emerging. Actually, many wastes are not fully recycled. For instance, potato peel is a cheap residue available from the potato industry. Up to now, potato peel has been used mostly for livestock feeding. Here, potato peel waste was subjected to direct acid liquefaction at 160 °C in 2-ethylhexanol and diethylene glycol using p-toluene sulfonic acid as catalyst. The product was characterized by infrared spectroscopy, chemical analysis, hydroxyl number and acid value. Results show that liquefaction was achieved in yields higher than 80%. The reactional profile shows two time zones, one comprising the process of liquefaction and one corresponding to the process of decomposition. Kinetics indicate that the liquefaction process occurs 1.9 times faster than the decomposition process. Overall, our findings show for the first time that, despite the water content, potato peel waste can be used to produce bio-oil. The products can be further used as fuels or refined chemicals such as levulinic acid, furfural, 5-hydroxyfurfural, dimethyl furfural and sugars in fermentation processes.  相似文献   
984.
Regional Environmental Change - Wetlands play important roles that benefit social-ecological systems. They are threatened by climate change and human activities, i.e., raising livestock and...  相似文献   
985.
986.
Local medical systems are key elements of social-ecological systems as they provide culturally appropriate and locally accessible health care options, especially for populations with scarce access to biomedicine. The adaptive capacity of local medical systems generally rests on two pillars: species diversity and a robust local knowledge system, both threatened by local and global environmental change. We first present a conceptual framework to guide the assessment of knowledge diversity and redundancy in local medicinal knowledge systems through a gender lens. Then, we apply this conceptual framework to our research on the local medicinal plant knowledge of the Tsimane’ Amerindians. Our results suggest that Tsimane’ medicinal plant knowledge is gendered and that the frequency of reported ailments and the redundancy of knowledge used to treat them are positively associated. We discuss the implications of knowledge diversity and redundancy for local knowledge systems’ adaptive capacity, resilience, and health sovereignty.  相似文献   
987.
Coral communities were examined from highly turbid near-shore marginal reefs of Abrolhos (Brazil) to test a paradigm previously developed from observations in clear water reefs; specifically, that coral photobiological properties follow a highly conserved linear relationship with optical depth (ζ) via preferential ‘non-photochemical’ over ‘photochemical’ dissipation of absorbed light energy. PAM flourometry in situ was used to examine the photobiology of the most dominant coral species throughout the platform surfaces and bases of Abrolhos’ characteristic ‘chapeir?es’ reef framework; however, none of the species consistently adhered to the ‘clear water paradigm’. PAM measurements further demonstrated that species conformed to two different strategies of non-photochemical energy dissipation: transient but relatively rapid for the two closely related endemic species (Mussismilia braziliensis and Mussismilia harttii) as opposed to more persistent for Montastrea cavernosa, Porites astreoides and Siderastrea stellata. Further experiments demonstrated that tolerance to anomalous stress amongst species did not correspond with the non-photochemical energy dissipation strategy present but was consistent with the relative dominance of species within the chapeir?es coral communities.  相似文献   
988.
Radio tracking of 142 males captured at 44 leks in Spain showed that partial migration of great bustard males in summer is a widespread behaviour in many Iberian populations, in contrast to their previously assumed sedentariness. A variable number of males migrated immediately after mating to summering areas with lower temperatures and human population densities and more trees and rainfall levels than the breeding sites. Birds selected there fields with trees and sunflower crops which provided shade during the hottest midday hours and protective cover against predators. Males breeding in areas with higher July temperatures had a higher tendency to migrate, and males from hotter, southern regions migrated longer distances than those from milder, northern regions and showed a preferred northward direction. These results confirmed various predictions from the weather sensitivity hypothesis, suggesting that summer migration of great bustard males represents primarily an adaptation to escape the summer heat of most breeding areas in central and southern Iberia. The hypothesis that males migrated to benefit from higher food availability at the summering areas could not be rejected by our results. Finally, migrating males also gained more tranquillity during the post-breeding moult due to the lower human population density at the summering areas. Summer migration of Iberian great bustard males may thus be interpreted as a form of behavioural thermoregulation which has not been described for other Palaearctic populations of this species or for other bird species breeding in temperate latitudes.  相似文献   
989.
990.
Over 40 years, the detrital aquifer of the Plana de Castellón (Spanish Mediterranean coast) has been subjected to seawater intrusion because of long dry periods combined with intensive groundwater exploitation. Against this backdrop, a managed artificial recharge (MAR) scheme was implemented to improve the groundwater quality. The large difference between the electrical conductivity (EC) of the ambient groundwater (brackish water due to marine intrusion) and the recharge water (freshwater) meant that there was a strong contrast between the resistivities of the brackish water saturated zone and the freshwater saturated zone. Electrical resistivity tomography (ERT) can be used for surveying similar settings to evaluate the effectiveness of artificial recharge schemes. By integrating geophysical data with lithological information, EC logs from boreholes, and hydrochemical data, we can interpret electrical resistivity (ER) with groundwater EC values and so identify freshwater saturated zones. Using this approach, ERT images provided a high-resolution spatial characterization and an accurate picture of the shape and extent of the recharge plume of the MAR site. After 5 months of injection, a freshwater plume with an EC of 400–600 μS/cm had formed that extended 400 m in the W-E direction, 250 m in the N-S direction, and to a depth of 40 m below piezometric level. This study also provides correlations between ER values with different lithologies and groundwater EC values that can be used to support other studies.  相似文献   
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