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21.
Jinzhi Wang Zhengyi Hu Xingkai Xu Xia Jiang Binghui Zheng Xiaoning Liu Xubin Pan Paul Kardol 《Waste management (New York, N.Y.)》2014,34(8):1546-1552
Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg?1 DM to 274.2, 30.4, and 314.0 mg kg?1 DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg?1 DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer. 相似文献
22.
Heather Henson-Ramsey Jay Levine Suzanne Kennedy-Stoskopf Sharon K. Taylor Damian Shea Michael K. Stoskopf 《Environmental Modeling and Assessment》2009,14(3):411-418
A simple and dynamic pharmacokinetic model was developed to predict bioconcentration of organic contaminants in earthworms.
The model was parameterized experimentally by placing Lumbricus terrestris in soil contaminated with 200 μg/cm2 of malathion. The toxicokinetics of malathion uptake, depuration, and degradation in soil is measured. After parameterization,
the model was able to accurately predict the bioconcentration factor of malathion at steady state. Sensitivity analyses were
performed and the rate of absorption was determined to be the most sensitive parameter. Varying the rate of malathion elimination
from earthworm tissues, malathion degradation, and the amount of malathion applied to the soil by 25-fold did not result in
the bioconcentration of malathion. An increase in the rate of malathion absorption into earthworm tissues by 25-fold did result
in bioconcentration. Previously published pharmacokinetic studies on xenobiotics with log K
ow values ranging up to 8.05 were used to test the predictive capacity of the model. The model was able to predict from 83%
to 105% of the experimentally derived bioconcentration factors. 相似文献
23.
24.
Naoko Takada-Oikawa Norihisa Katoh Toshio Oshida Sukeo Kawanabe Toshikazu Kaise 《Journal of Material Cycles and Waste Management》2000,2(2):138-142
A potting experiment was carried out to determine the effects of soil amendments containing polysaccharides and earthworms
on a land application system for the purification of animal waste water. The following soil amendments were used: purified
Konjak powder (KP, powder containing glucomannan made from the root system of devil's tongue, Amorphophalus rivieri Dur.), crystallized cellulose (CC), and a mixture of the two (MX). These soil amendments were added to the pots, and then
Chrysanthemum corondria were planted in the earthworm pots (A pots), the nonearthworm pots (B pots), and the control pots (C pots); the first two
plots received primary-treated animal waste water, and the other one received tap water. The following items were then measured:
pH, electrical conductivity, chemical oxygen demand (CODMn), total nitrogen (TN), total phosphorus, the volume of drained water from each pots, the height and dry matter weight of
plants, and the water permeability into the soil. The MX-A pots, i.e., the pots containing both soil amendments and earthworms,
gave good results, especially for water permeability, plant growth, the purification of CODMn, and TN. These results suggest that the presence of soil amendments and earthworms may enhance the improvement of water quality
in land application systems using vegetation.
Received: December 9, 1998 / Accepted: February 8, 2000 相似文献
25.
P. Mangala C.S. De Silva Asoka Pathiratne Cornelis A.M. van Gestel 《Environmental pollution (Barking, Essex : 1987)》2010,158(10):3041-3047
Effects of pesticides on structural and functional properties of ecosystems are rarely studied under tropical conditions. In this study litterbag and earthworm field tests were performed simultaneously at the same tropical field site sprayed with chlorpyrifos (CPF). The recommended dose of CPF (0.6 kg a.i. ha−1) and two higher doses (4.4-8.8 kg a.i. ha−1) significantly decreased litter decomposition during the first 3 months after application, which could be explained from lower earthworm and termite abundances during this period. Species-specific effects of CPF on organism abundance and biomass were observed, with termites being mostly affected followed by the earthworm Perionyx excavatus; the earthworm Megascolex sp. was least affected. Recovery was completed within 6 months. Decomposition in the controls and lowest two treatments was completed within 4 months, which suggests the need for modification of standard test guidelines to comply with faster litter degradation under tropical conditions. 相似文献
26.
Mature Lumbricus terrestris were host soils and leaf litter were collected from a former arsenic mine in Devon, UK (Devon Great Consols), a former gold mine in Ontario, Canada (Deloro), and an uncontaminated residential garden in Nottingham, UK. Arsenic concentrations determined by inductively coupled plasma-mass spectrometry (ICP-MS) in soils were 16-348 mg kg−1, 6.0-239 mg kg−1 in the earthworms and 8.6 mg kg−1 in leaf litter sampled at Deloro (all dry weight). High performance liquid chromatography (HPLC-ICP-MS) analysis revealed arsenite (AsIII), arsenate (AsV) and five organoarsenic species; arsenobetaine (AB), methylarsonate (MAV), dimethylarsinate (DMAV), arsenosugar 1 (glycerol sugar), arsenosugar 2 (phosphate sugar), and trimethylarsineoxide (TMAO) in field-collected L. terrestris. Differences were observed in the variety of organoarsenic species present between field sites. Several organoarsenic species were observed in the leaf litter (DMAV, arsenosugar 2 and TMAO) but not AB. Depuration resulted in higher concentrations of inorganic As being detected in the earthworm whereas the concentration or variety of organoarsenic species was unchanged. Commercially sourced L. terrestris were exposed to As contaminated soil in laboratory mesocosms (1.0, 98, 183, 236, 324 and 436 mg kg−1) without leaf litter and were additionally analyzed using X-ray absorption near edge structure (XANES). Only inorganic AsIII and AsV was observed. It is proposed that ingestion of leaf litter and symbiotic processes in the natural soil environment are likely sources of organoarsenic compounds in field-collected L. terrestris. 相似文献
27.
Impact of the earthworm Lumbricus terrestris (L.) on As, Cu, Pb and Zn mobility and speciation in contaminated soils 总被引:2,自引:0,他引:2
Sizmur T Palumbo-Roe B Watts MJ Hodson ME 《Environmental pollution (Barking, Essex : 1987)》2011,159(3):742-748
To assess the risks that contaminated soils pose to the environment properly a greater understanding of how soil biota influence the mobility of metal(loid)s in soils is required. Lumbricus terrestris L. were incubated in three soils contaminated with As, Cu, Pb and Zn. The concentration and speciation of metal(loid)s in pore waters and the mobility and partitioning in casts were compared with earthworm-free soil. Generally the concentrations of water extractable metal(loid)s in earthworm casts were greater than in earthworm-free soil. The impact of the earthworms on concentration and speciation in pore waters was soil and metal specific and could be explained either by earthworm induced changes in soil pH or soluble organic carbon. The mobilisation of metal(loid)s in the environment by earthworm activity may allow for leaching or uptake into biota. 相似文献
28.
In this study we investigated the use of activated carbon (AC) as a soil amendment for reducing bioavailability of polychlorinated biphenyls (PCBs) to the earthworm Eisenia fetida. Artificial soil was contaminated with PCBs and used in bioaccumulation experiments fresh or after aging for 19 months. PCB bioaccumulation in earthworms was reduced by 68% when AC was placed as a layer without mixing and by 94% when AC was manually mixed into the soil. Aging of the same AC mixed soil for 19 months resulted in an overall reduction of 99% in PCB biouptake. AC-treated aged soil also showed two orders of magnitude lower equilibrium aqueous concentrations of PCBs compared to untreated aged soils. The findings from this study indicate that application of engineered sorbents like AC to PCB impacted soils may greatly reduce PCB uptake at the base of the terrestrial food chain. 相似文献
29.
Susceptibility of epigeic earthworm Eisenia fetida to agricultural application of six insecticides 总被引:1,自引:0,他引:1
Ecotoxicological risks of agricultural application of six insecticides to soil organisms were evaluated by acute toxicity tests under laboratory condition following OECD guidelines using the epigeic earthworm Eisenia fetida as the test organism. The organochlorine insecticide endosulfan (LC50 - 0.002 mg kg−1) and the carbamate insecticides aldicarb (LC50 - 9.42 mg kg−1) and carbaryl (LC50 - 14.81 mg kg−1) were found ecologically most dangerous because LC50 values of these insecticides were lower than the respective recommended agricultural dose (RAD). Although E. fetida was found highly susceptible to the pyrethroid insecticide cypermethrin (LC50 - 0.054 mg kg−1), the value was higher than its RAD. The organophosphate insecticides chlorpyrifos (LC50 - 28.58 mg kg−1), and monocrotophos (LC50 - 39.75 mg kg−1) were found less toxic and ecologically safe because the LC50 values were much higher than their respective RAD. 相似文献
30.
Heavy metal and nutrient changes during vermicomposting animal manure spiked with mushroom residues 总被引:1,自引:0,他引:1
Xiuchao Song Manqiang Liu Di Wu Lin Qi Chenglong Ye Jiaguo Jiao Feng Hu 《Waste management (New York, N.Y.)》2014,34(11):1977-1983
A pilot-scale trial of four months was conducted to investigate the responses of heavy metal and nutrient to composting animal manure spiked with mushroom residues with and without earthworms. Results showed that earthworm activities accelerated organic matter mineralization (e.g. reduction in C/N ratio, increase in total concentrations of N, P, K) and humification (e.g. increase in humic acid concentration, humification ratio and humification index). Despite composting increased total heavy metal (i.e. As, Pb, Cu, Zn) concentrations irrespective of earthworm, the availability of heavy metals extracted by DTPA significantly (P < 0.05) decreased particularly in treatments with earthworms introduced. The shift from available to unavailable fractions of heavy metals was either due to earthworm bioaccumulation, as indicated by total heavy metal concentrations being higher in earthworm tissues, or due to the formation of stable metal-humus complexes as indicated by the promotion of humification. Our results suggest that vermicomposting process could magnify the nutrient quality but relieve the heavy metals risk of agricultural organic wastes. 相似文献