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1.
人工湿地在新西兰的应用 总被引:20,自引:0,他引:20
人工湿地作为二级或三级废水处理技术在新西兰已被广泛采用。有些小规模的人工湿地已使用了近 30年。在新西兰的镇或小城市产生的污水用人工湿地系统进行深度处理已成为一种时尚。为了更好地发挥人工湿地在污水处理方面的作用 ,新西兰皇家科学院水和大气研究所对新西兰人工湿地进行了广泛的调查研究。结果表明 ,自 2 0世纪 90年代以来 ,人工湿地的使用趋于增长 ,目前新西兰大约有80个人工湿地系统在使用。1 人工湿地仅作为生活污水和工业废水处理之用 人工湿地主要可分为二大类 :一种是地面流动 ,废水流过一个种植挺水植物如灯心草、芦… 相似文献
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In New Zealand shellfish are a significant food resource and shellfish are harvested for both recreational and commercial
use. Commercially harvested Greenshell mussels (Perna canaliculus) and Pacific oysters (Crassostrea gigas) from aquaculture farms dominate consumption in New Zealand. Other commercial species include cockles (Austrovenus stuchburyii) and surf clam species which are wild harvested. The consumption of shellfish has been associated with gastroenteritis outbreaks
caused by noroviruses following faecal contamination of growing waters with human waste. In New Zealand, since 1994 over 50
norovirus outbreaks linked to consumption of either New Zealand commercially grown oysters or imported oysters have been reported.
An IEC/ISO 17025 accredited method for detection of noroviruses in bivalve shellfish was established in 2007. This method
has been used in outbreak investigations to analyse implicated shellfish, in virus prevalence surveys and monitoring programmes,
and commercially for product clearances. Surveys have shown that enteric viruses occur frequently in non-commercial shellfish,
especially near sewage outfalls and following sewage discharge events. Viral source tracking methods have assisted in identifying
pollution sources. The commercial shellfish industry operates under the Bivalve Molluscan Shellfish Regulated Control Scheme
(BMSRCS), administered by the New Zealand Food Safety Authority. Recently regulatory measures were introduced into the BMSRCS
to manage viruses. These include the closure of harvest areas for at least 28 days after human sewage contamination events
and norovirus outbreaks. These management strategies, coupled with new information on norovirus prevalence in shellfish, have
helped to improve the quality and safety of New Zealand shellfish. 相似文献
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A mathematical model of urinary nitrogen and water flow in soil has been developed that incorporated stochastic rainfall and stochastic temperature events. This model was used to characterise the variability in urine patch nitrogen leaching at Taupo, New Zealand. This stochastic model was also used to more accurately determine the effect of urinary patch overlap on cow urinary nitrogen flow and leaching in soil. Nitrogen leaching from single urine deposits on pasture in the winter ranged from 0 to 75% of applied nitrogen as a result of stochastic rainfall events. Rainfall effects explained 98% of the variance in nitrogen leaching due to stochastic rainfall and temperature effects combined. The model predicted that on average 38, 61, and 71% of the nitrogen in single, double and triple urine patches is leached in the winter. Nitrogen leaching rates were significantly greater in the winter than the summer months. The distribution in the amount of nitrogen leached from single urine patches was close to normal in the winter but approximately exponentially distributed in the summer. The variability in total nitrogen leached from a field also decreased as the stocking rate increased. A quantitative modelling framework is crucial for understanding nitrogen transport in pastoral systems and for effectively setting and enforcing restrictions imposed by regulatory bodies on nitrogen losses from pastoral farming and this study represents a component of this framework. 相似文献
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This paper questions whether current control of the pasture weed nassella tussock (Nassella trichotoma (Nees) Hack. ex Arech) is worthwhile, and how management can be improved. A computer model is developed to simulate nassella tussock population growth, and to provide a basis for calculating economic effects. The existing policy objective of eradication is shown to be inappropriate for economic and practical reasons. Cost-benefit analysis indicates that current government control programmes yield positive net benefits at a 10% discount rate, under realistic population growth-rate assumptions. An economic threshold model confirms that control should be undertaken at current levels of infestation. An optimization model suggests that greater net benefits would be obtained with less frequent control operations than currently practiced. 相似文献
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Kenneth F.D. Hughey 《Journal of Cleaner Production》2011,19(5):532-541
Coordinated voluntary approaches to Pollution Prevention are widely practiced in many western-style economies. However, little empirical research has been undertaken into the extent to which these approaches match best practice pollution prevention approaches. In this paper nine programs employed by five regional and district councils in New Zealand are evaluated against nine ‘Best Practice’ design features. All five councils’ pollution prevention programs contained some of the best practice design features in their program’s design. Perhaps not surprisingly the older programs rank highest out of the five. However, all programs have the potential to develop towards containing all of the ‘best practice’ design features, with most emphasis needed on the credibility of program monitoring. From an ongoing research perspective, and also from an overall PP program performance point of view, the biggest challenge remains the extent and depth that the programs apply each of the design features. As presented they are extremely generic. While generic design features provide for flexibility in implementation, often seen as a positive, they can also be a recipe for ‘tokenism’, something that future researchers and program managers need to be aware of. We also sought to determine if these programs were contributing to sustainable management in New Zealand. Findings in this respect were equivocal. This finding in part is due to the lack of specificity around targets, monitoring and reporting, items needing further attention from managers and researchers. 相似文献
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Indika Herath Markus Deurer David HorneRanvir Singh Brent Clothier 《Journal of Cleaner Production》2011,19(14):1582-1589
Hydroelectricity has been rated to have a large water footprint (WF) on global average. We assessed the WF of hydroelectricity by three different methods using New Zealand as a case study. The first (WF-1) and second (WF-2) methods only consider the consumptive water use of the hydroelectricity generation system, while our third method (WF-3) accounts for the net water balance. Irrespective of the method, the WF of New Zealand’s hydroelectricity was found much smaller than the commonly cited international value of 22 m3 GJ−1. Depending on the method, the national WF ranged from 1.55 m3 GJ−1 (WF-3) to 6.05 m3 GJ−1 (WF-1). The WF- 3 considers the net water balance including rainfall, which is the key driver for replenishing water resources. It provides meaningful information that helps our understanding of the differences of the WF in locations, which are diverse in terms of water resource availability. We highlight the effects of local climatic differences and the structural specifics of a hydroelectricity scheme on the WF. The large variation in the WF of hydropower across New Zealand illustrates the inappropriateness of using global average values. Local values, calculated using our hydrologically rational method, must be used. 相似文献
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我国的区域发展战略演变大体可划分为均衡发展阶段、非均衡发展阶段和区域协调发展阶段,而区域协调发展阶段以党的十八大为节点又可以分为前后两个时期.不同时期的生产力布局策略对区域空间结构和空间管制制度均有直接影响,进而产生不同的资源环境问题,并最终推动环境管理制度和管理重点发生变化.当前我国区域协调发展战略更加重视区域一体化... 相似文献
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L.A. Schipper G.P. SparlingL.M. Fisk M.B. DoddI.L. Power R.A. Littler 《Agriculture, ecosystems & environment》2011,144(1):95-101
In New Zealand, phosphate (P) fertilisers used in agriculture are the main sources of the potentially toxic elements cadmium (Cd) and uranium (U), which occur as unwanted contaminants. New Zealand is developing draft soil guideline values (SGV) for maximum concentrations of Cd. To assess when soils under pasture for sheep production might reach a particular SGV, we analysed archived soil samples from a 23 yr P fertiliser trial. The pasture sites were at Whatawhata, North Island, New Zealand, and had received P fertiliser at the rates of 0, 30, 50 and 100 kg P ha−1 yr−1. From 1983 to 1989, P was applied as single superphosphate, from 1989 to 2006, P was applied as triple superphosphate. Soils from replicate paddocks were sampled annually to a depth of 75 mm on easy (10-20°) and steep (30-40°) slope classes. Total P, Cd and U were analysed by ICP-MS after acid digestion. Data were analysed by fitting trend lines using linear mixed models for two slope classes and for two sampling periods 1983-1989 and 1989-2006 when the soil sampling method and fertiliser type had been changed.The changes in total P, Cd and U were directly related to the type and amount of P fertiliser applied, the control treatment showed no significant change in P, Cd or U. At 50 and 100 kg P ha−1 yr−1 there were generally linear increases in total P and total U, and the same trend line applied to both time periods, but the rate of increase in P was greater on the easy slope class. For Cd, a “broken stick” model was needed to explain the data. Pre-1989, Cd increased in the 50 and 100 kg P ha−1 yr−1 treatment (0.036-0.045 mg kg−1 yr−1, respectively): post 1988 the rate of increase declined markedly on those two treatments (0.005-0.015 mg kg−1 yr−1, respectively), and declined absolutely in the 30 kg P ha−1 yr−1 treatments. The maximum content of Cd was in the 100 kg P ha−1 yr−1 treatment which reached 0.931 mg Cd kg−1 on the easy slope. For U there were steady linear increases for the 30, 50 and 100 kg P ha−1 treatments, and no significant difference between the steep and easy slopes, nor the two sampling periods, the maximum concentration obtained was 2.80 mg U kg−1 on the 100 kg P ha−1 treatment. The results suggest that at rates of P fertiliser likely to be applied to hill farms (<50 kg P ha−1 yr−1), and using P fertiliser with low Cd content, then the Cd concentration in this soil will never reach a SGV of 1 mg kg−1. 相似文献
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Eggshell colour does not predict measures of maternal investment in eggs of <Emphasis Type="Italic">Turdus</Emphasis> thrushes 总被引:1,自引:0,他引:1
Cassey P Ewen JG Blackburn TM Hauber ME Vorobyev M Marshall NJ 《Die Naturwissenschaften》2008,95(8):713-721
The striking diversity of avian eggshell colour has long fascinated biologists. Recently, it has been proposed that the blue-green colour of some eggs may function as a post-mating sexually selected signal of female phenotypic quality to their mates to induce higher allocation of paternal care. It has been suggested that maternally deposited yolk carotenoids may be the specific aspect of reproductive quality that the female is signalling via eggshell colour. We use the known properties of the thrush visual system (Turdus sp.) to calculate photon capture for the four single cone photoreceptors, and the principal member of the double cone class for eggs in clutches of two introduced European thrush species (Turdus merula and Turdus philomelos) in New Zealand. We show that differences in the avian-perceived colours of individual eggs are not consistently correlated with different measures of maternal investment in the egg. Given the growing extent of the knowledge between maternal quality, parental investment and eggshell pigmentation across avian taxa, we encourage the use of avian perceptual modelling for testing alternative non-signalling explanations for the structural and physiological basis of these relationships. 相似文献
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Legume-based pastures in Australasia are predominantly perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.). These pastures have disadvantages such as limitations in the production and persistence of white clover and ryegrass in drought prone regions. With the increasing interest in organic agriculture, more complex pasture mixtures are seen as an alternative to the standard ryegrass-white clover (RWC) pasture. Although anecdotal evidence exists to support the benefits of alternative pastures, there is insufficient scientific evidence to support or refute these claims. The present study was conducted to compare three different alternative multi-species (mixed herb leys) (MSP) pastures with the standard RWC pasture with and without irrigation, in terms of biomass and biological nitrogen fixation (BNF) over a period of 1 year under field conditions in Canterbury, New Zealand. Isotopic dilution technique involving field 15N-microplots were used to measure BNF. Irrigation doubled dry matter yields (DMY) of all pastures compared with those under dryland. There was no significant difference between DMY of all pastures under dryland. However, under irrigation, MSP pastures out-yield RWC pasture in total and legume DMY. Red clover MSP produced significantly lower DMY than the comprehensive or lucerne MSP treatment, probably due to the ability of lucerne in extracting water from deeper soil depth. Seasonal changes in plant composition varied according to the species sown, soil moisture status and temperature. Total and seasonal amounts of N2 fixed followed the same trend as the DMY and were related to the DMY of legumes. On average, about 26–34 kg N was fixed per tonne of legume DMY, showing a uniformity across all pastures. Overall, based on the present results of 1-year study, the MSP pastures tend to result in higher DMY, BNF and legume growth compared with that of the RWC pasture, provided irrigation is available. With increased BNF, these irrigated MSP pastures may provide high quality feed to grazing animals. 相似文献
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《Agriculture, ecosystems & environment》1986,16(1):69