Diversity of Cicadellidae in agricultural production areas in the Ovens Valley, Northeast Victoria, Australia

There is a paucity of data on the distribution of Cicadellidae (leafhoppers) in Australia. This study quantifies the relative abundance, seasonal activity and diversity of leafhoppers in the Ovens Valley region of north-east Victoria, Australia. Species diversity and abundance was assessed at four field sites in and around the field borders of commercially grown tobacco crops using three sampling techniques (pan trap, sticky trap and sweep net). Over 51 000 leafhopper samples were collected, with 57 species from 11 subfamilies and 19 tribes identified. Greater numbers and diversity of leafhoppers were collected in yellow pan traps. The predominant leafhopper collected was Orosius orientalis (Matsumura). Twenty-three leafhopper species were recorded for the first time in Victoria and eight economically important pest species were recorded. Seasonal activity of selected leafhopper species, covering two sampling seasons, is presented.

A situated approach to historical thinking in the Australian Curriculum : History

This paper focuses on the importance of foregrounding an emphasis on the development of historical thinking in the implementation of the Australian Curriculum: History as a way of making the study of history meaningful for their students. In doing so, it argues that teachers need to take up the opportunity to situate the study of Asia as a significant component of the curriculum’s ‘Australia in a world history approach’. In the discussion on the significance of historical thinking, the paper specifically addresses those seven historical concepts articulated in the new history curriculum by drawing from the international scholarship in the field of history education on the ways in which children and adolescents think about historical content and concepts.

Molecular characterisation, pathogenesis and fungicide sensitivity of Pythium spp. from table beet (Beta vulgaris var. vulgaris) grown in the Lockyer Valley, Queensland

Table beet production in the Lockyer Valley of south-eastern Queensland is known to be adversely affected by soilborne root disease from infection by Pythium spp. However, little is known regarding the species or genotypes that are the causal agents of both pre- and post-emergence damping off. Based on RFLP analysis with HhaI, HinfI and MboI of the PCR amplified ITS region DNA from soil and diseased plant samples, the majority of 130 Pythium isolates could be grouped into three genotypes, designated LVP A, LVP B and LVP C. These groups comprised 43, 41 and 7% of all isolates, respectively. Deoxyribonucleic acid sequence analysis of the ITS region indicated that LVP A was a strain of Pythium aphanidermatum, with greater than 99% similarity to the corresponding P. aphanidermatum sequences from the publicly accessible databases. The DNA sequences from LVP B and LVP C were most closely related to P. ultimum and P. dissotocum, respectively. Lower frequencies of other distinct isolates with unique RFLP patterns were also obtained with high levels of similarity (>97%) to P. heterothallicum, P. periplocum and genotypes of P. ultimum other than LVP B. Inoculation trials of 1- and 4-week-old beet seedlings indicated that compared with isolates of the LVP B genotype, a higher frequency of LVP A isolates caused disease. Isolates with the LVP A, LVP B and LVP C genotypes were highly sensitive to the fungicide Ridomil MZ, which suppressed radial growth on V8 agar between approximately four and thirty fold at 5 μg/mL metalaxyl and 40 μg/mL mancozeb, a concentration far lower than the recommended field application rate.

Meaning of public space and sense of community: The case of new neighbourhoods in the Kathmandu Valley

This paper examines the meaning of public space and sense of community among neighbourhood residents in the changing urban context of the Kathmandu Valley in Nepal. Two new neighbourhoods were selected for the purpose of this study with data collected from interviews with the residents. The study has found that most residents of the new neighbourhoods have an understanding of the significance of public space in community life. However, such understandings are based less on the actual use of public space. The existing public spaces in these neighbourhoods are less successful in offering a meaning to the residents, due to their poor development and the lack of active use. Despite these changes, some residents believe they have developed a sense of community, which is an outcome of other individual factors than the use of public space. It is argued that the role of contemporary neighbourhood public space in fostering a sense of community appears to be less significant in the valley’s present context.

Structure and Historical Changes in the Groundfish Complex of the Eastern Bering Sea

The eastern Bering Sea is a major marine ecosystem containing some of the largest populations of groundfish, crabs, birds, and marine mammals in the world. Commercial catches of groundfish in this region have averaged about 1.6 million tons (t) annually in 1970-86. This report describes the species and relative importance of species in the eastern Bering Sea groundfish complex, the environment in which they live, and the history of the fisheries and management during the years 1954 - 1985. Historical changes in abundance and the condition of the principal species at the end of this first 30 years of exploitation are also examined. Results suggest that the biomass of the groundfish complex is characterized by variability rather than stability. The most reliable data (1979 to 1985) suggests that the biomass of the complex fluctuated between 11.8 and 15.7 million t. Even greater variability is suggested by the less reliable data from earlier years. Because of its dominance in the complex and wide fluctuations in abundance, walleye pollock (Theragra chalcogramma) is primarily responsible for the major variations in abundance of the complex. After 30 years of exploitation, the complex was generally in excellent condition. (PDF file contains 100 pages.)

Downscaling of surface moisture flux and precipitation in the Ebro Valley (Spain) using analogues and analogues followed by random forests and multiple linear regression

In this paper, reanalysis fields from the ECMWF have been statistically downscaled to predict from large-scale atmospheric fields, surface moisture flux and daily precipitation at two observatories (Zaragoza and Tortosa, Ebro Valley, Spain) during the 1961-2001 period. Three types of downscaling models have been built: (i) analogues, (ii) analogues followed by random forests and (iii) analogues followed by multiple linear regression. The inputs consist of data (predictor fields) taken from the ERA-40 reanalysis. The predicted fields are precipitation and surface moisture flux as measured at the two observatories. With the aim to reduce the dimensionality of the problem, the ERA-40 fields have been decomposed using empirical orthogonal functions. Available daily data has been divided into two parts: a training period used to find a group of about 300 analogues to build the downscaling model (1961-1996) and a test period (19972001), where models' performance has been assessed using independent data. In the case of surface moisture flux, the models based on analogues followed by random forests do not clearly outperform those built on analogues plus multiple linear regression, while simple averages calculated from the nearest analogues found in the training period, yielded only slightly worse results. In the case of precipitation, the three types of model performed equally. These results suggest that most of the models' downscaling capabilities can be attributed to the analogues-calculation stage.

Investigation of rising nitrate concentrations in groundwater in the Eden Valley, Cumbria: Phase 1 project scoping study

This is the Investigation of rising nitrate concentrations in groundwater in the Eden Valley, Cumbria report produced by the Environment Agency in 2003. This report focuses on groundwater nitrate concentrations in the Eden Valley. Most boreholes in the Eden Valley had nitrate concentrations less than 20 mg/l but a significant number had higher concentrations, some exceeding the EC maximum admissible concentration for drinking water of 50 mg/l. The main objectives of this report were to investigate the causes of rising nitrate concentrations in groundwater in the Permo-Triassic sandstone aquifers of the Eden Valley area and provide sufficient understanding of the groundwater and surface water flow system, including the sources of the nitrate contamination and the processes controlling nitrate movement, so that possible management options for reversing this trend can be considered.

Sources and transport of dissolved and particulate organic carbon in the Mississippi River estuary and adjacent coastal waters of the northern Gulf of Mexico

Dissolved organic carbon (DOC), stable carbon isotopic (delta(13)C) compositions of DOC and particulate organic carbon (POC), and elemental C/N ratios of POC were measured for samples collected from the lower Mississippi and Atchafalaya rivers and adjacent coastal waters in the northern Gulf of Mexico during the low flow season in June 2000 and high flow season in April 2001. These isotopic and C/N results combined with DOC measurements were used to assess the sources and transport of terrestrial organic matter from the Mississippi and Atchafalaya rivers to the coastal region in the northern Gulf of Mexico. delta(13)C values of both POC (-23.8parts per thousand to -26.8parts per thousand) and DOC (-25.0parts per thousand to -29.0parts per thousand) carried by the two rivers were more depleted than the values measured for the samples collected in the offshore waters. Strong seasonal variations in delta(13)C distributions were observed for both POC and DOC in the surface waters of the region. Fresh water discharge and horizontal mixing played important roles in the distribution and transport of terrestrial POC and DOC offshore. Our results indicate that both POC and DOC exhibited non-conservative behavior during the mixing especially in the mid-salinity range. Based on a simple two end-member mixing model, the comparison of the measured DOC-delta(13)C with the calculated conservative isotopic mixing curve indicated that there was a significant in situ production of marine-derived DOC in the mid- to high-salinity waters consistent with our in situ chlorophyll-a measurements. Our DOC-delta(13)C data suggest that a removal of terrestrial DOC mainly occurred in the high-salinity (>25) waters during the mixing. Our study indicates that the mid- to high- (10-30) salinity range was the most dynamic zone for organic carbon transport and cycling in the Mississippi River estuary. Variability in isotopic and elemental compositions along with variability in DOC and POC concentrations suggest that autochthonous production, bacterial utilization, and photo-oxidation could all play important roles in regulating and removing terrestrial DOC in the northern Gulf of Mexico and further study of these individual processes is warranted. (C) 2004 Elsevier B.V. All rights reserved.

Allochthonous and autochthonous mire deposits, slope instability and palaeoenvironmental investigations in the Borve Valley, Barra, Outer Hebrides, Scotland

Ashmore, P. Brayshay, B.A Edwards, K.J Gilbertson, D. Grattan, J. Kent, M. Pratt, K. Weaver, R. 'Allochthonous and autochthonous mire deposits, slope instability and palaeoenvironmental investigations in the Borve Valley, Barra, Outer Hebrides, Scotland' The Holocene 2000 10, 1 pp.97-108