|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Biochar improves diary pasture yields by alleviating P and K constraints with no influence on soil respiration or N2O emissions显示文摘Dairy pastures can be a major source of soil nitrous oxide(N_(2)O)emissions due to the combination of intensive nitrogen(N)fertiliser use and high soil water content,from either rainfall and/or irrigation.Biochar application is a promising approach to lower soil greenhouse gas emissions,particularly under high soil moisture conditions where denitrification is the primary N-transformation pathway.In a replicated field trial,we evaluated the effects of two contrasting biochars derived from poul-try litter and from hardwood on soil N_(2)O emissions,soil ammonium(NH4^(+))and nitrate(NO3^(−))status,pasture productivity and herbage nutrient content.A liming treatment to mimic the liming equivalence of the poultry litter biochar was used to separate any effects observed from changes in soil pH.To further separate the effects of biochars on soil N status,N_(2)O emissions and pasture N uptake,high and low N fertiliser doses(annual application of 672 kg N ha^(−1),336 kg N ha^(−1))were superimposed across all of the treatments.The N fertiliser dose had no significant impact on pasture yield.Application of poultry litter biochar resulted in significant increases in pasture productivity under both high and low N inputs.This was achieved by alleviating soil P,and possibly K nutritional constraints that are typical in Australian Ferralsols.Under the high N fertiliser dose,emissions of N_(2)O from the treatments and control were not significantly different(p>0.05)and ranged between 1.14 and 1.78 kg N_(2)O-N ha^(−1)across the 11-month study.The low N dose resulted in significantly lower emissions of N_(2)O of between 0.80 and 0.84 kg N_(2)O-N ha^(−1),but biochar had no significant effect on net emissions across the season.The lack of impact of biochar on N_(2)O emissions was attributed to the relatively dry conditions over the trial period resulting in nitrification being the most likely N-transformation pathway.During brief episodes of high soil moisture,peak emissions from the biochar plots were lower than from the control or lime treatment,but these differences did not impact on the emis-sion budget over the 11-month sampling campaign. | Lukas van Zwieten Stephen Kimber Stephen Morris Lynne M.Macdonald Josh Rust Scott Petty Stephen Joseph Terry Rose | 2019 | Biochar2019，1，1： | 2 |
| 2 | A developmental approach for measuring the severity of crimes显示文摘 | Rajeev Ramchand John M.MacDonald Amelia Haviland Andrew R.Morral | | 0，，： | 1 |
| 3 | 对英国水獭(Lutra lutra)种群生长的长期监测显示文摘欧洲水獭自50年代来明显减少,正在从许多河流消失。本研究基于对英国西部3个自然建群的集水区和英国东部2个通过人工投放加速建群的集水区的长期监测(从1977年以来)结果。到2002年,在每条河流至少收集了16年的数据,在每条研究河上设置一系列研究点,记录水獭出现点的百分率、痕迹点的痕迹数,并通过结合以上2个参数计算年种群指数。在一条自然建群的西部河流,头5年水獭种群生长快速增长,接着生长缓慢。但在2个研究开始就已经有水獭的集水区,其生长比较稳定。东部河流水獭建群的速度缓慢,随时间有巨大的波动。年种群生长率约为1%~7%,在早期较高。对水獭的年度监测计划提出了建议。 | Christopher F.Mason Sheila M.Macdonald 伍建榕 | 2004 | AMBIO-人类环境杂志2004，33，3： | 1 |
| 4 | Toxicity of perfluorooctane sulfonic acid and perfluorooctanoic acid to Chironomus tentans显示文摘 | Michelle M.MacDonald Amanda L.Warne Naomi L.Stock Scott A.Mabury Keith R.Solomon Paul K.Sibley | 2009 | Environmental Toxicology and Chemistry2009，，9： | 1 |
| 5 | Central venous stenosis in the hemodialysis patient:incidence and efficacy of endovascular treatmen显示文摘 | A.Lumsden M.MacDonald H.Isiklar L.Martin D.Kikeri L.Harker | | 0，，： | 1 |
| 6 | Formation potential and analysis of 32 regulated and unregulated disinfection by-products: Two new simplified methods显示文摘Water disinfection is an essential process that provides safe water by inactivating pathogens that cause waterborne diseases. However, disinfectants react with organic matter naturally present in water, leading to the formation of disinfection by-products(DBPs). Multi-analyte methods based on mass spectrometry(MS) are preferred to quantify multiple DBP classes at once however, most require extensive sample pre-treatment and significant resources. In this study, two analytical methods were developed for the quantification of 32 regulated and unregulated DBPs. A purge and trap(P&T) coupled with gas chromatography mass spectrometry(GC-MS) method was optimized that automated sample pre-treatment and analyzed volatile and semi-volatile compounds, including trihalomethanes(THMs), iodinated trihalomethanes(I-THMs), haloacetonitriles(HANs), haloketones(HKTs) and halonitromethanes(HNMs). LOQs were between 0.02-0.4 μg/L for most DBPs except for 8 analytes that were in the low μg/L range. A second method with liquid chromatography(LC) tandem mass spectrometry(MS/MS) was developed for the quantification of 10 haloacetic acids(HAAs) with a simple clean-up and direct injection. The LC-MS/MS direct injection method has the lowest detection limits reported(0.2-0.5 μg/L). Both methods have a simple sample pre-treatment, which make it possible for routine analysis. Hyperchlorination and uniform formation conditions(UFC) formation potential tests with chlorine were evaluated with water samples containing high and low TOC. Hyperchlorination formation potential test maximized THMs and HAAs while UFC maximized HANs. Ascorbic acid was found to be an appropriate quencher for both analytical methods. Disinfected drinking water from four water utilities in Alberta, Canada were also evaluated. | Jillian N.Murakami Xu Zhang Joanne Ye Amy M.MacDonald Jorge Perez David W.Kinniburgh Susana Y.Kimura | 2022 | Journal of Environmental Sciences2022，34，7： | 1 |
| 7 | Do H<sub>2</sub>‐receptor antagonists cause acute pancreatitis?显示文摘 | Josie M. M.Evans Alex D.McMahon Douglas T.Steinke Ritchie R.McAlpine Thomas M.Macdonald | 1999 | Pharmacoepidem Drug Safe1999，，6： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员