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271.
Use of wastewater and compost extracts as nutrient sources for growing nursery and turfgrass species
Michitsch RC Chong C Holbein BE Voroney RP Liu HW 《Journal of environmental quality》2007,36(4):1031-1041
Nutrient salts present in liquid by-products following waste treatment are lost resources if not effectively recycled, and can cause environmental problems if improperly disposed. This research compared the growth response and mineral nutrient status of two nursery and two turfgrass species, hydroponically supplied with nutritive by-product extracts derived from anaerobically digested municipal solid waste (MSW) and aerobically composted organic wastes from the mushroom and MSW industries. Forsythia (Forsythia x intermedia 'Lynwood') and weigela (Weigela florida 'Red Prince'), and creeping bentgrass (Agrostis palustris Huds.) and Kentucky bluegrass (Poa pratensis L.), were grown in nutrient solutions/extracts prepared from: (i) half-strength Hoagland's #2 solution (HH; control), (ii) Plant Products liquid fertilizer (PP; g kg(-1): 180 N; 39 P; 224 K), (iii) spent mushroom compost (SMC), (iv) MSW compost (GMC), and (v) intra-process wastewater from the anaerobic digestion of MSW (ADW). Additional nutrient solutions (SMC-A, GMC-A, and ADW-A) were prepared by amending the original solutions with N, P, and/or K to concentrations in HH (mg L(-1): 105 N; 15 P; 118 K). Plants receiving the SMC-A extract grew best or at least as well as those in HH, PP, and the amended GMC-A and ADW-A solutions. This study indicated that, with proper amendments of N, P, K and other nutrients, water-soluble constituents derived from organic waste treatment have potential for use as supplemental nutrient sources for plant production. 相似文献
272.
We sampled 240 wadeable streams across Wisconsin for different forms of phosphorus and nitrogen, and assemblages of macroinvertebrates
and fish to (1) examine how macroinvertebrate and fish measures correlated with the nutrients; (2) quantify relationships
between key biological measures and nutrient forms to identify potential threshold levels of nutrients to support nutrient
criteria development; and (3) evaluate the importance of nutrients in influencing biological assemblages relative to other
physicochemical factors at different spatial scales. Twenty-three of the 35 fish and 18 of the 26 macroinvertebrate measures
significantly correlated (P < 0.05) with at least one nutrient measure. Percentages of carnivorous, intolerant, and omnivorous fishes, index of biotic
integrity, and salmonid abundance were fish measures correlated with the most nutrient measures and had the highest correlation
coefficients. Percentages of Ephemeroptera–Plecoptera–Trichoptera individuals and taxa, Hilsenhoff biotic index, and mean
tolerance value were macroinvertebrate measures that most strongly correlated with the most nutrient measures. Selected biological
measures showed clear trends toward degradation as concentrations of phosphorus and nitrogen increased, and some measures
showed clear thresholds where biological measures changed drastically with small changes in nutrient concentrations. Our selected
environmental factors explained 54% of the variation in the fish assemblages. Of this explained variance, 46% was attributed
to catchment and instream habitat, 15% to nutrients, 3% to other water quality measures, and 36% to the interactions among
all the environmental variables. Selected environmental factors explained 53% of the variation in macroinvertebrate assemblages.
Of this explained variance, 42% was attributed to catchment and instream habitat, 22% to nutrients, 5% to other water quality
measures, and 32% to the interactions among all the environmental variables. 相似文献
273.
Raymond Philippe Paul Sylvianne Perron André Bellehumeur Christian Larocque Émilie Charest Hugues 《Food and environmental virology》2022,14(1):40-58
Food and Environmental Virology - Human noroviruses are among the main causes of acute gastroenteritis worldwide. Frozen raspberries have been linked to several norovirus food-related outbreaks.... 相似文献
274.
Geology has been highlighted by a number of authors as a key factor in high indoor radon levels. In the light of this, this study examines the application of seasonal correction factors to indoor radon concentrations in the UK. This practice is based on an extensive database gathered by the National Radiological Protection Board over the years (small-scale surveys began in 1976 and continued with a larger scale survey in 1988) and reflects well known seasonal variations observed in indoor radon levels. However, due to the complexity of underlying geology (the UK arguably has the world's most complex solid and surficial geology over the shortest distances) and considerable variations in permeability of underlying materials it is clear that there are a significant number of occurrences where the application of a seasonal correction factor may give rise to over-estimated or under-estimated radon levels. Therefore, the practice of applying a seasonal correction should be one that is undertaken with caution, or not at all. This work is based on case studies taken from the Northamptonshire region and comparisons made to other permeable geologies in the UK. 相似文献
275.
276.
James E. Bonany Paul J. Van Geel H. Burak Gunay O. Burkan Isgor 《Waste management (New York, N.Y.)》2013,33(5):1215-1228
A landfill operated in Ste. Sophie, Québec, Canada was instrumented to better understand the waste stabilization process in northern climates. Instrument bundles were placed within the waste to monitor temperature, settlement, oxygen, moisture content, total load, mounding of leachate and electrical conductivity. A finite element model was developed to simulate the heat budget for the first waste lift placed in the winter months and was calibrated using the first 10.5 months of collected temperature data. The calibrated model was then used to complete a sensitivity analysis for the various parameters that impact the heat budget. The results of the analysis indicated that the heat required for phase change to thaw the liquid fraction within frozen waste had a significant impact on the heat budget causing sections of waste to remain frozen throughout the simulation period. This was supported by the data collected to date at Ste. Sophie and by other researchers indicating that frozen waste placed during the winter months can remain frozen for periods in access of 1.5 years. 相似文献
277.
Herman Hedriana Kimberly Martin Daniel Saltzman Paul Billings Zachary Demko Peter Benn 《黑龙江环境通报》2020,40(2):179-184
Objectives
The performance of noninvasive prenatal screening (NIPS) for fetal aneuploidy in twin pregnancies is dependent on the amount of placentally derived cell-free DNA, the “fetal fraction (FF),” present in maternal plasma. We report FF values in monozygotic (MZ) and dizygotic (DZ) pregnancies.Methods
We reviewed FF in pregnancies at 10 to 20 completed weeks gestational age based on single-nucleotide polymorphism (SNP)-based NIPS where zygosity was routinely established in twin pregnancies. The cohort included 121 446 (96.3%) singleton, 1454 (1.2%) MZ, and 3161 (2.5%) DZ pregnancies. For DZ twins, individual FFs were measured.Results
Combined FF for DZ and MZ fetuses were 35% and 26% greater than singletons, respectively. The individual FF contributions from each fetus in DZ twins were, on average, 32% less than singletons. FF in DZ twin pairs were moderately correlated (Pearson correlation coefficient.66). When a threshold of 2.8% FF was applied to define uninterpretable results, 1.7% (2102/121 446) of singletons, 0.8% (11/1454) of MZ pairs, and 5.6% (178/3161) of DZ pairs were uninterpretable.Conclusion
For optimal aneuploidy NIPS in twin pregnancies, zygosity should be established and in DZ twins FF for both fetuses should be determined to identify those cases where results can be reliably interpreted. 相似文献278.
279.
280.
Carol M. Werner Paul H. White Sari Byerly Robert Stoll 《Journal of environmental psychology》2009,29(2):193-202
Two experiments examined clinical validation's ability to increase examination of a persuasive message and increase long-term recycling. In Experiment 1, validating (acknowledging) recycling's inconvenience decreased criticism of the persuasive message, supporting validation's ability to reduce reactance and open the reader to new ideas. Validation did not improve attitudes towards the sign's author, removing liking for the communicator as an alternate explanation for attitude change. In Experiment 2, different recycling signs were created from a 2(no validation/validation) by 2(weak/strong arguments) factorial design, and placed in university buildings. The validation weak sign increased recycling more than the validation strong sign, especially after the signs were removed. We suggest that validation induced people to scrutinize the weak message and use their existing pro-recycling attitudes to “creatively elaborate” it. Discussion emphasizes clinical validation and the Elaboration Likelihood Model as theoretical tools, as well as the potential for thought provoking signs to have long-term effects. 相似文献