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981.
982.
Lilly Lim-Camacho Anoma Ariyawardana Gemma K. Lewis Steven J. Crimp Simon Somogyi Brad Ridoutt Stuart Mark Howden 《Regional Environmental Change》2017,17(1):93-103
Despite there being considerable research and knowledge surrounding the risks of climate change on agricultural productivity, fewer studies have examined risks from a whole-of-chain perspective (i.e. from producer to consumer) and the perceptions of consumers about the climate adaptation strategies of food businesses. This paper presents the findings of a survey of 1532 Australian consumers and how they might respond to a food company’s climate adaptation strategy. Three respondent archetypes, ‘Eco-warriors’ (n = 557), ‘Undecideds’ (n = 600) and ‘Abdicators’ (n = 375), were identified based on their perceptions of risks associated with climate change and their attitudes towards climate adaptation. Further analysis was carried out to understand how each group of respondents would respond to adaptation strategies employed by food companies. Based on the findings of this study, two main challenges are presented for food value chains: (1) translating consumer needs and preferences to niche opportunities arising from adaptation and (2) understanding how best to communicate adaptation benefits based on varying attitudes and information needs. By addressing these challenges, synergies between adaptation goals and competitive strategies in food value chains may be achieved. 相似文献
983.
The use of coarse recycled concrete aggregates (CRCA) in conjunction with fine recycled concrete aggregates (FRCA) as sub-base materials has been widely studied. Although research results indicate that it is feasible to employ both CRCA and FRCA as granular sub-base, the influence of the unhydrated cement in the adhered mortar of the RCA on the properties of the sub-base materials has not been thoroughly studied. Generally, it is known that the strength of the sub-base materials prepared with RCA increases over time. However, this mechanism, known as the self-cementing properties, is not well understood and is believed to be governed by the properties of the fine portion of the RCA (<5mm). This paper presents an investigation on the cause of the self-cementing properties by measuring X-ray diffraction patterns, pH values, compressive strength and permeability of various size fractions of the FRCA obtained from a commercially operated construction and demolition waste recycling plant. Their influence on the overall sub-base materials was determined. The results indicate that the size fractions of <0.15 and 0.3-0.6mm (active fractions) were most likely to be the principal cause of the self-cementing properties of the FRCA. However, the effects on the properties of the overall RCA sub-base materials were minimal if the total quantity of the active fractions was limited to a threshold by weight of the total fine aggregate. 相似文献
984.
Earthworm cytochrome P450 determination and application as a biomarker for diagnosing PAH exposure 总被引:1,自引:0,他引:1
Zhang W Song YF Gong P Sun TH Zhou QX Liu M 《Journal of environmental monitoring : JEM》2006,8(9):963-967
We developed a new microsome purification method and used the Omura and Sato method to measure the total content of cytochrome (Cyt) P450 in earthworm (Eisenia fetida) microsomes. In method development, two different pretreatments, i.e. solubilization or manual separation were used to purify worm microsomes. Solubilization was more effective than manual separation and difference spectra showed a peak at 450 +/- 1 nm in microsomes received solubilization pretreatment. We conducted a 48 h contact test by exposing worms on pyrene (Py) and benzo[a]pyrene (BaP) spiked filter paper. A dose-response relationship was established between total P450 content and the concentration of Py or BaP ranging from 10(-6) mg mL(-1) to 10(-2) mg mL(-1). Results show that total Cyt P450 content in earthworms is a promising biomarker for diagnosing PAHs exposure at sublethal dose ranges. 相似文献
985.
He X Izaurralde RC Vanotti MB Williams JR Thomson AM 《Journal of environmental quality》2006,35(4):1608-1619
Soil carbon sequestration (SCS) has the potential to attenuate increasing atmospheric CO2 and mitigate greenhouse warming. Understanding of this potential can be assisted by the use of simulation models. We evaluated the ability of the EPIC model to simulate corn (Zea mays L.) yields and soil organic carbon (SOC) at Arlington, WI, during 1958-1991. Corn was grown continuously on a Typic Argiudoll with three N levels: LTN1 (control), LTN2 (medium), and LTN3 (high). The LTN2 N rate started at 56 kg ha(-1) (1958), increased to 92 kg ha(-1) (1963), and reached 140 kg ha(-1) (1973). The LTN3 N rate was maintained at twice the LTN2 level. In 1984, each plot was divided into four subplots receiving N at 0, 84, 168, and 252 kg ha(-1). Five treatments were used for model evaluation. Percent errors of mean yield predictions during 1958-1983 decreased as N rate increased (LTN1 = -5.0%, LTN2 = 3.5%, and LTN3 = 1.0%). Percent errors of mean yield predictions during 1985-1991 were larger than during the first period. Simulated and observed mean yields during 1958-1991 were highly correlated (R2 = 0.961, p < 0.01). Simulated SOC agreed well with observed values with percent errors from -5.8 to 0.5% in 1984 and from -5.1 to 0.7% in 1990. EPIC captured the dynamics of SOC, SCS, and microbial biomass. Simulated net N mineralization rates were lower than those from laboratory incubations. Improvements in EPIC's ability to predict annual variability of crop yields may lead to improved estimates of SCS. 相似文献
986.
Simon ML Cherry DS Currie RJ Zipper CE 《Environmental monitoring and assessment》2012,184(4):2559-2574
The Ely Creek watershed (Lee County, VA) was determined in 1995 to be the most negatively affected by acid mine drainage (AMD)
within the Virginia coalfield. This determination led the US Army Corps of Engineers to design and build passive wetland remediation
systems at two major AMD seeps affecting Ely Creek. This study was undertaken to determine if ecological recovery had occurred
in Ely Creek. The results indicate that remediation had a positive effect on all monitoring sites downstream of the remediated
AMD seeps. At the site most impacted by AMD, mean pH was 2.93 prior to remediation and improved to 7.14 in 2004. Benthic macroinvertebrate
surveys revealed that one AMD influenced site had increased taxa richness from zero taxa in 1997 to 24 in 2004. While in situ testing of Asian clams resulted in zero survival at five of seven AMD influenced sites prior to remediation, some clams survived
at all sites after. Clam survival was found to be significantly less than upstream references at only two sites, both downstream
of un-mitigated AMD seeps in 2004. An ecotoxicological rating (ETR) system that combined ten biotic and abiotic parameters
was developed as an indicator of the ecological status for each study site. A comparison of ETRs from before and after remediation
demonstrated that all sites downstream of the remediation had experienced some level of recovery. Although the remediation
has improved the ecological health of Ely Creek, un-mitigated AMD discharges are still negatively impacting the watershed. 相似文献
987.
Fan Z Keum YS Li QX Shelver WL Guo LH 《Journal of environmental monitoring : JEM》2012,14(5):1345-1352
Indirect competitive immunoassays were developed on protein microarrays for the sensitive and simultaneous detection of multiple environmental chemicals in one sample. In this assay, a DNA/SYTOX Orange conjugate was employed as an antibody label to increase the fluorescence signal and sensitivity of the immunoassays. Epoxy-modified glass slides were selected as the substrate for the production of 4 × 4 coating antigen microarrays. With this signal-enhancing system, competition curves for 17β-estradiol (E2), benzo[a]pyrene (BaP) and 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) were obtained individually on the protein microarray. The IC(50) and calculated limit of detection (LOD) are 0.32 μg L(-1) and 0.022 μg L(-1) for E2, 37.2 μg L(-1) and 24.5 μg L(-1) for BaP, and 31.6 μg L(-1) and 2.8 μg L(-1) for BDE-47, respectively. LOD of E2 is 14-fold lower than the value reported in a previous study using Cy3 labeled antibody (Du et al., Clin. Chem, 2005, 51, 368-375). The results of the microarray immunoassay were within 15% of chromatographic analysis for all three pollutants in spiked river water samples, thus verifying the immunoassay. Simultaneous detection of E2, BaP and BDE-47 in one sample was demonstrated. There was no cross-reaction in the immunoassay between these three environmental chemicals. These results suggest that microarray-based immunoassays with DNA/dye conjugate labels are useful tools for the rapid, sensitive, and high throughput screening of multiple environmental contaminants. 相似文献
988.
Single-pass electrofishing was used to define the most efficient sampling distance to assess stream condition using the index of biotic integrity (IBI) methodology in headwater (<36 km2 drainage area), warmwater streams in the Eastern Corn Belt Plain ecoregion. Based on wetted widths (1–3.3 m) of sampled reaches, we defined effort based on increased area (range 50–555 m2). Sampled area necessary to capture a representative fish assemblage increased until 167-m2 distance, which is equivalent to a minimum sampling distance of one habitat cycle. No significant difference in metric actual observed value response was found with increasing habitat cycle. Increased effort is required in smaller streams widths (≤1 m) to achieve the recommended sample area. The effect of rare fish on the IBI was tested using a modified Walford method. A significant decrease in IBI score was observed when 10 % of the rare data were removed. The presence of rare fish did not influence individual IBI metrics or scores for either the increased effort or reduced effort calibrations until greater than 3 % of the data was removed for number of species, 15 % removal of data for number of minnow species, and 5 % removal of data for catch per unit effort (CPUE). Increased effort did not affect any metric or IBI score, while reduced effort influenced the number of darter, madtom, and sculpin species and catch per unit effort metric scores but did not affect IBI score. 相似文献
989.
990.
Coral communities of the remote atoll reefs in the Nansha Islands, southern South China Sea 总被引:1,自引:0,他引:1
M. X. Zhao K. F. Yu Q. Shi T. R. Chen H. L. Zhang T. G. Chen 《Environmental monitoring and assessment》2013,185(9):7381-7392
During the months of May and June in the year 2007, a survey was conducted regarding coral reef communities in the remote atolls (Zhubi Reef and Meiji Reef) of Nansha Islands, southern South China Sea. The goals of the survey were to: (1) for the first time, compile a scleractinian coral check-list; (2) estimate the total richness, coral cover, and growth forms of the community; and (3) describe preliminary patterns of community structure according to geomorphological units. Findings of this survey revealed a total of 120 species of scleractinia belonging to 40 genera, while the average coral cover was 21 %, ranging from less than 10 % to higher than 50 %. Branching and massive corals were also found to be the most important growth forms of the whole coral community, while Acropora, Montipora, and Porites were the three dominant genera in the overall region, with their contributions to total coral cover measuring 21, 22, and 23 %, respectively. Overall, coral communities of the Nansha Islands were in a relative healthy condition with high species diversity and coral cover. Spatial pattern of coral communities existed among various geomorphological units. Mean coral cover was highest in the patch reef within the lagoon, followed by the fore reef slope, reef flat, and lagoon slope. The greatest contributors to total coral cover were branching Acropora (45 %) in the lagoon slope, branching Montipora (44 %) in the reef flat, and massive Porites (51 %) in the patch reef. Coral cover in the fore reef revealed a greater range of genera than in other habitats. The leeward fore reef slope had higher coral cover (>50 %) when compared with the windward slope (<10 %). The coral communities of the inner reef flat were characterized by higher coral cover (27 %) and dominant branching Montipora corals, while lower coral cover (4 %) was dominated by Psammocora with massive growth forms on the outer reef flat. Destructive fishing and coral bleaching were two major threats to coral communities in the study area. 相似文献