Measuring the impact of sewage effluent on the macroinvertebrate community of an upland stream: The effect of different levels of taxonomic resolution and quantification

Abstract Benthic macroinvertebrates were sampled from four sites on upland streams in the Wentworth Falls area of the Blue Mountains, NSW. One site received effluent from a sewage treatment plant and the others were reference sites. Five replicate collections were taken from each site on four occasions at intervals of 3 months. Macroinvertebrate community data were analysed using univariate (ANOVA) and multivariate (NMDS) techniques and comparisons were made between analyses at different levels of taxonomic aggregation and using different methods of data transformation. Similar patterns were observed at both species and family levels, and even the order level showed a clear community response to effluent input. Binary (presence/ absence) data provided similar results to quantitative data for the species and family levels. However, when binary data were used at the order level, the distinctions between the reference sites became blurred. We discuss the implications of these findings for environmental monitoring.     

Atmospheric deposition of sulphur and nitrogen species in the U.K.

1. The foundations of our understanding of acid deposition were laid in the last century, but the scale and scope of damage to sensitive receptors has only been subject to intensive investigation over the last 30 years or so. Negotiations are now well underway to reduce emissions, and for some pollutants policy is in place, so that these receptors may be protected adequately. Crucial to this has been the 'critical loads' approach adopted in the U.K. and elsewhere in Europe over the last 6 years.
2. This paper describes the source of acidic emissions, how these emissions are transformed in the atmosphere and subsequently deposited. Measurements of wet deposition are made at a number of sites in the U.K. and some of the results from the networks are presented. These results allow wet and dry deposition to be mapped and the methodologies and underlying assumptions to these procedures are described, and S deposition has been estimated for the U.K. Acid Waters Monitoring Network sites.     

一种加工型马铃薯品种的农杆菌转化体系研究

大西洋马铃薯是经济价值很高的炸片型加工品种,逆境胁迫下,易产生褐变、空心等问题,影响加工品质。为获取抗逆境胁迫的优质转基因新品种,采用根癌农杆菌介导法,以大西洋马铃薯的茎段为外植体,建立了快速,简便,高效的遗传转化体系。从共培养到转化植株获得只需7-8周,转化频率达80%。结果表明茎段是较好的转化受体,硫代硫酸银可以有效促进不定芽分化并提高再生频率。PCR、Southern杂交分析证明外源基因已经成功整合到马铃薯再生植株的基因组中。该转化体系为大量开发转基因马铃薯植株,进而筛选优质的马铃薯炸片加工型新品种奠定基础。     

Isolation and characterization of polymorphic trinucleotide microsatellites of the polyploid crucian carp (Carassius auratus)

In this study, we isolated and characterized nine polymorphic trinucleotide microsatellites (CAG and CCT) from the crucian carp (Carassius auratus). The number of alleles per locus ranged from two to six. Five loci showed a significantly excess homozygosity, and a genetic linkage between CAL0102 and CAL0495 was strongly suggested. Our results confirmed the triploidy of Korean individuals, and the microsatellites were found to be useful for analysing the allelic state of the polyploid crucian carp.     

Contrasting levels of genetic diversity between the historically rare orchid Cypripedium japonicum and the historically common orchid Cypripedium macranthos in South Korea

Many terrestrial orchids are historically rare and occur in small, spatially isolated populations. Theory predicts that such species will harbour low levels of genetic variation within populations and will exhibit a high degree of population genetic divergence, primarily as a result of genetic drift. If the origin of the present‐day populations is relatively recent from the same genetically depauperate source population, a complete lack of genetic differentiation between conspecific populations is expected. If a terrestrial orchid was historically common with moderate or high levels of genetic diversity, but has experienced more recent anthropogenic disturbance as a result of over‐collection, it would still exhibit initial levels of genetic variation within populations and a low degree of genetic divergence between populations. To test these predictions, we examined the genetic diversity in six populations (N = 131) of the historically and currently rare Cypripedium japonicum and in four populations (N = 94) of the historically common but now rare C. macranthos from South Korea. Fourteen putative allozyme loci resolved from eight enzyme systems revealed no variation either within or among populations of C. japonicum, which supports the first prediction. In contrast, populations of C. macranthos harboured high levels of genetic variation (mean percentage of polymorphic loci %P = 46.7; mean expected heterozygosity H_e = 0.185) and exhibited a low degree of population genetic divergence (G_ST = 0.059), supporting the second prediction. The lack of genetic variation both within and among conspecific populations of C. japonicum may suggest that populations originated from the same genetically depauperate ancestral population. The high levels of genetic diversity maintained in populations of C. macranthos suggest that the collection‐mediated decrease in the number of individuals is still too recent for long‐term effects on genetic variation. Based on current demographic and genetic data, in situ and ex situ conservation strategies should be provided to preserve genetic variation and to ensure the long‐term survival of the two species in the Korean Peninsula. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 119–129.