4,014 research outputs found
An assessment of the value of pastoral development in Northland
This paper presents the results of an economic study of
farm development in Northland. In this study, records
were collected of 32 dairy farm case histories which had
increased butterfat production by 105% in an average of
6 years, and 18 sheep farm case histories for which wool
production increased 116% over a 7-year period. Also
included are data supplied by the Lands and Survey Department
on the economic outcome of two land development
blocks. In this paper, attention is focused on the cash costs and
benefits of development and their valuation by economic
methods. Nevertheless, the deficiencies of this approach
are recognized, because cash costs and benefits are only one
dimension of the outcome of development and the method
used for valuing this outcome makes assumptions about
the values of the farmer and society.This research was generously funded by the Commercial Rank of Australia
to mark their 100th Anniversary
Recommended from our members
Millimetre and submillimetre molecular line observations of the reflection nebula NGC 2023
Observations in the CO J = 2 - 1, CO J = 3 - 2 and HCO+ J = 4 - 3 transitions of the molecular cloud associated with NGC 2023 are presented. The observations reveal the complex structure of the gas in the surrounding cloud, and show the presence of several hot-spots which may represent separate bodies of gas. A search has been made for the source of excitation of two nearby groups of Herbig-Haro objects recently discovered by Malin et al. (1987). No such objects can be clearly identified from the data. CO J = 3 - 2 spectra taken at positions lying on the CO J = 1 - 0 shell observed by Gatley et al. (1987) show marked enhancements in peak line strength relative to coincident CO J = 2 - 1 data. By contrast, no such enhancements are observed away from the shell. Observations of the submillimeter wavelength HCO+ J = 4 - 3 transition show that the line strength is greatest in the vicinity of the shell structure. Simple large velocity gradient modeling of the excitation conditions of the shell material suggests that the gas may be hot (Tkin ~ 140 K), dense, and optically thin
Low energy proton bidirectional anisotropies and their relation to transient interplanetary magnetic structures: ISEE-3 observations
It is known that the interplanetary medium in the period approaching solar maximum is characterized by an enhancement in the occurrence of transient solar wind streams and shocks and that such systems are often associated with looplike magnetic structures or clouds. There is observational evidence that bidirectional, field aligned flows of low energy particles could be a signature of such looplike structures, although detailed models for the magnetic field configuration and injection mechanisms do not exist at the current time. Preliminary results of a survey of low energy proton bidirectional anisotropies measured on ISEE-3 in the interplanetary medium between August 1978 and May 1982, together with magnetic field data from the same spacecraft are presented
Evaluating remediation of radionuclide contaminated forest near Iwaki, Japan, using radiometric methods
Radiometric surveys have been conducted in support of a project investigating the potential of biofuel power generation coupled with remediation of forests contaminated with radionuclides following the Fukushima Daiichi accident. Surveys conducted in 2013 and 2014 were used to determine the distribution and time dependence of radionuclides in a cedar plantation and adjacent deciduous forestry subject to downslope radionuclide migration, and a test area where litter removal was conducted. The radiocaesium results confirmed enhanced deposition levels in the evergreen areas compared with adjacent areas of deciduous forestry, implying significant differences in depositional processes during the initial interception period in 2011. Surveys were conducted both with and without a collimator on both occasions, which modified the angular response of the detector to separate radiation signals from above and below the detector. The combined data have been used to define the influence of radionuclides in the forest canopy on dose rate at 1 m, indicating that, in evergreen areas, the activity retained within the canopy even by 2013 contributed less than 5% of ground level dose rate. The time dependent changes observed allow the effect of remediation by litter removal in reducing radionuclide inventories and dose rates to be appraised relative natural redistribution processes on adjacent control areas. A 15x45 m area of cedar forest was remediated in September 2013. The work involved five people in a total of 160 person hours. It incurred a total dose of 40-50 µSv, and generated 2.1 t of waste comprising forest litter and understory. Average dose rates were reduced from 0.31 µSv h-1 to 0.22 µSv h-1, with nuclide specific analyses indicating removal of 30 ± 3% of the local radiocaesium inventory. This compares with annual removal rates of 10-15% where radionuclide migration down-slope over ranges of 10-50 m could be observed within adjacent areas. Local increases were also observed in areas identified as sinks. The results confirm the utility of time-series, collimated, radiometric survey methods to account for the distribution and changes in radionuclide inventory within contaminated forests. The data on litter removal imply that significant activity transfer from canopy to soil had taken place, and provide benchmark results against which such remediation actions can be appraised
Challenges to evaluation of multilingual geographic information retrieval in GeoCLEF
This is the third year of the evaluation of
geographic information retrieval (GeoCLEF)
within the Cross-Language Evaluation Forum
(CLEF). GeoCLEF 2006 presented topics and
documents in four languages (English,
German, Portuguese and Spanish). After two
years of evaluation we are beginning to
understand the challenges to both Geographic
Information Retrieval from text and of
evaluation of the results of geographic
information retrieval. This poster enumerates
some of these challenges to evaluation and
comments on the limitations encountered in the
first two evaluations
GeoCLEF 2006: the CLEF 2006 Ccross-language geographic information retrieval track overview
After being a pilot track in 2005, GeoCLEF advanced to be a regular track within CLEF 2006. The
purpose of GeoCLEF is to test and evaluate cross-language geographic information retrieval (GIR): retrieval for
topics with a geographic specification. For GeoCLEF 2006, twenty-five search topics were defined by the
organizing groups for searching English, German, Portuguese and Spanish document collections. Topics were
translated into English, German, Portuguese, Spanish and Japanese. Several topics in 2006 were significantly
more geographically challenging than in 2005. Seventeen groups submitted 149 runs (up from eleven groups and
117 runs in GeoCLEF 2005). The groups used a variety of approaches, including geographic bounding boxes,
named entity extraction and external knowledge bases (geographic thesauri and ontologies and gazetteers)
Validated Radiometric Mapping in 2012 of Areas in Japan Affected by the Fukushima-Daiichi Nuclear Accident.
On March 11 2011 the north-eastern region of Japan was hit by a magnitude 9 earthquake, which occurred underneath the sea-bed 70 km east of the Oshika peninsula in Tohoku. The north-eastern shore of Honshu was hit by a tsunami resulting from this earthquake. As a consequence, reactors 1-4 at the nuclear power station Fukushima-Daiichi suffered a completed loss of power and cooling causing a partial core meltdown in units 1, 2 and 3 followed by a series of explosions and the release of large quantities of radioactivity into the environment. The accident was rated level 7 (the highest level) on the International Nuclear Event Scale. While most of the emissions were driven towards the Pacific Ocean, a significant amount of radioactive material was deposited onto the Japanese land-mass, resulting in enhanced localised radiation exposure.
This report covers measurements and detailed radiation maps conducted by a UK University team working with Japanese colleagues during a series of visits in 2012. They have been presented and shared locally in Japan at time of acquisition. Since then the data have been cross-validated relative to soil samples from a reference site established at the University of Fukushima, and analysed independently in the UK and in Japan. This report provides detailed descriptions of the data sets, validated radiometric maps for 134Cs, 137Cs and the overall gamma dose rates, together with a full account of the establishment of the calibration site. The work reported here demonstrates the utility of detailed radiometric maps in helping to understand the distribution of radionuclides in complex environmental systems. This information is potentially of use to help avoid unnecessary external radiation exposure in the outdoor environment, to help to visualise and target areas for remediation, to evaluate the effectiveness of clean-up and soil removal activities, to examine uptake of radioactivity from the environment through agricultural systems, and to monitor redistribution over time of the activity in the environment. The report includes full copies of digital data sets for the demonstration surveys.
Radiometric methods provide means of measuring radioactivity with recognised roles in nuclear emergency response, and environmental applications. In the aftermath of nuclear accidents they are crucial to evaluate the environmental impact of the accident and guide remediation measures. The Scottish Universities Environmental Research Centre (SUERC) is a research centre attached to the University of Glasgow with extensive experience of radiometric mapping using airborne and ground based systems, conducting most of the UK post-Chernobyl radiation mapping using airborne systems and coordinating European projects to harmonise and cross-calibrate systems for nuclear emergency response purposes. In the early stages of major accidents the most pressing needs are for rapid, large scale, information. Airborne surveys of the affected area were conducted initially by a joint US/Japanese team and later on by The Ministry of Education Science and Technology (MEXT) and the Japanese Atomic Energy Agency (JAEA), eventually providing national scale radiation maps with a spatial resolution of several hundred meters. In later stages of accident recovery there are increasing needs for more detailed spatial information and increasing requirements for objective, traceable and cross validated analysis. Systems for this work need to be mobile, preferably portable, efficient, robust and well calibrated, providing detailed real time information directly on location. The SUERC Portable Gamma Spectrometry system fulfils these criteria. It provides a spatial resolution of better than 10 m for mapped data and allows a real time identification of spatial features down to 10-20 cm.
In the work reported here, calibration sites have been established in Fukushima at the campus of Fukushima University and the Fukushima Prefecture Fruit Tree Research Institute to provide objective and internationally traceable validation of ground based instruments. High resolution HPGe spectrometry of soil samples conducted at laboratories at Fukushima University and SUERC was used for validation of the field instrument. Values of 137Cs activity concentration measured by the two laboratories were in full agreement to high precision. Agreement for the 134Cs activity concentration values was within 5-10%. The soil samples used in this process were analysed as a function of depth, revealing that while the majority of activity was retained in near surface layers, a small component of approximately 1% of the total activity appears to have migrated more rapidly to greater depths. This suggests complex transport behaviour in the soil columns which should be investigated further. The calibration sites are open for future use. These data establish a traceable record between local facilities and internationally acknowledged standards for future use.
Deployment of the SUERC system in vehicles has demonstrated the ability of relatively small detectors to measure regional scale deposition patterns over a wide range of radioactivity levels, varying from 10,000 Bq per square meter up to more than 10 million Bq per square meter. These activity levels are broadly consistent with the national scale airborne maps for the study areas, but the ground based maps provide very high level of local detail, which allow small scale changes to be readily observed and related to the local soils, land cover and built environment. Areas covered in two surveys in March and July 2012, respectively, cover parts of the Fukushima Prefecture including parts of the evacuation and exclusion zones as well as areas directly affected by the 2011 tsunami. Short backpack surveys in urban areas associated with the car trips were also conducted e.g. in Fukushima City (in the heart of the prefecture), Ōkuma (within 3 km of the Fukushima Daichi reactors), Minami-Daira and Kawauchi-mura (within the initial evacuation zones), demonstrate the versatility of a system which can be rapidly moved from a vehicle to backpack where further detailed information is needed.
With a fully spectrometric system as used in this study, it is possible to identify specific radioactive isotopes and to quantify the activity concentrations of natural and artificial sources spanning many orders of magnitude, from less than 10 kBq m-2 to above 10 MBq m-2 for radiocaesium. This information has been used to estimate the contribution to the dose rate from different sources, so that a comparison between the contributions from naturally occurring radioactive materials (not affected by the accident) and the different radiocaesium isotopes present following the accident can be readily made. These data provide vital information to the local population and emergency services in guiding remediation efforts, and also over the course of time, in observing the extent to which weathering and radioactivity decay processed are gradually reducing the relative contributions from the accident. In the long term it is hoped that this type of representation will help put the accident contributions into perspective, and to register improvements with time which may help to establish increased confidence in affected areas.
In urbanised areas backpack systems provide the means of producing detailed surveys in locations where people spend their time. Surveys conducted of Fukushima University and Fukushima Iizaka have demonstrated the ability of detailed radiometric mapping to identify locations with highly varying levels of contamination, from more highly contaminated areas around drain pipes to the relatively low levels of contamination on roads and other hard surfaces where rain and snow melt have removed deposited activity. The effectiveness of the remediation work conducted on the University campus was evident, showing the ability of radiometric surveys to demonstrate the effectiveness of remediation and to identify where remaining activity is located. The remediation methods employed resulted in a three- to fourfold reduction in dose rate compared to untreated areas.
Remediation efforts in orchards or woodland are particularly challenging. Given the economic importance of agriculture in the Fukushima area and the possible pathways from contaminated produce into the human body, a precise evaluation of the local radiation risk is of prime importance. The SUERC system has been demonstrated in orchards at the Fukushima Prefecture Fruit Tree Research Institute, and at other orchards in the Prefecture. Work has also been undertaken with agricultural research institutions at Tsukuba, Ibaraki Prefecture. The comparison of measurements taken at these same sites over the time of a year show a decrease in activity following the half-life of the radioisotopes deposited, superimposed by environmental factors like precipitation, illustrating self-remediation. Ongoing work on these sites will allow an assessment of transfer of activity from to the fruit, and the impact of measures to remediate the orchards or reduce uptake of activity in the fruit, and the evaluation of external doses to workers in the orchards.
The data collected during this work contain the specific activity per isotope at a given surveyed location and at a given moment in time. The data accompanying this report are transparent, open and independently validated. They are made available for reference purposes and further utilisation.
The work presented here highlights many of the difficult challenges ahead in the monitoring and remediation effort in the area affected by the accident in the Fukushima Dai-ichi nuclear power plant. It demonstrates the capabilities and methods at the disposal of the international community in aiding the Japanese efforts, demonstrating the value of international collaboration in helping to address some of the difficult problems associated with recovery from a serious nuclear accident. It is hoped that these data, and the methods which they demonstrate, will contribute, together with future work, to increased understanding of the environmental impacts of the accident, and that future cooperative work involving Japanese and international teams will contribute to recovery and restoration of confidence in affected areas and communities
Multi-model simulations of the impact of international shipping on Atmospheric Chemistry and Climate in 2000 and 2030
The global impact of shipping on atmospheric chemistry and radiative forcing, as well as the associated uncertainties, have been quantified using an ensemble of ten state-of-the-art atmospheric chemistry models and a predefined set of emission data. The analysis is performed for present-day conditions ( year 2000) and for two future ship emission scenarios. In one scenario ship emissions stabilize at 2000 levels; in the other ship emissions increase with a constant annual growth rate of 2.2% up to 2030 ( termed the "Constant Growth Scenario" (CGS)). Most other anthropogenic emissions follow the IPCC ( Intergovernmental Panel on Climate Change) SRES ( Special Report on Emission Scenarios) A2 scenario, while biomass burning and natural emissions remain at year 2000 levels. An intercomparison of the model results with observations over the Northern Hemisphere (25 degrees - 60 degrees N) oceanic regions in the lower troposphere showed that the models are capable to reproduce ozone (O-3) and nitrogen oxides (NOx= NO+ NO2) reasonably well, whereas sulphur dioxide (SO2) in the marine boundary layer is significantly underestimated. The most pronounced changes in annual mean tropospheric NO2 and sulphate columns are simulated over the Baltic and North Seas. Other significant changes occur over the North Atlantic, the Gulf of Mexico and along the main shipping lane from Europe to Asia, across the Red and Arabian Seas. Maximum contributions from shipping to annual mean near-surface O-3 are found over the North Atlantic ( 5 - 6 ppbv in 2000; up to 8 ppbv in 2030). Ship contributions to tropospheric O3 columns over the North Atlantic and Indian Oceans reach 1 DU in 2000 and up to 1.8 DU in 2030. Tropospheric O-3 forcings due to shipping are 9.8 +/- 2.0 mW/m(2) in 2000 and 13.6 +/- 2.3 mW/m(2) in 2030. Whilst increasing O-3, ship NOx simultaneously enhances hydroxyl radicals over the remote ocean, reducing the global methane lifetime by 0.13 yr in 2000, and by up to 0.17 yr in 2030, introducing a negative radiative forcing. The models show future increases in NOx and O-3 burden which scale almost linearly with increases in NOx emission totals. Increasing emissions from shipping would significantly counteract the benefits derived from reducing SO2 emissions from all other anthropogenic sources under the A2 scenario over the continents, for example in Europe. Globally, shipping contributes 3% to increases in O-3 burden between 2000 and 2030, and 4.5% to increases in sulphate under A2/CGS. However, if future ground based emissions follow a more stringent scenario, the relative importance of ship emissions will increase. Inter-model differences in the simulated O-3 contributions from ships are significantly smaller than estimated uncertainties stemming from the ship emission inventory, mainly the ship emission totals, the distribution of the emissions over the globe, and the neglect of ship plume dispersion
Biocurators and Biocuration: surveying the 21st century challenges
Curated databases are an integral part of the tool set that researchers use on a daily basis for their work. For most users, however, how databases are maintained, and by whom, is rather obscure. The International Society for Biocuration (ISB) represents biocurators, software engineers, developers and researchers with an interest in biocuration. Its goals include fostering communication between biocurators, promoting and describing their work, and highlighting the added value of biocuration to the world. The ISB recently conducted a survey of biocurators to better understand their educational and scientific backgrounds, their motivations for choosing a curatorial job and their career goals. The results are reported here. From the responses received, it is evident that biocuration is performed by highly trained scientists and perceived to be a stimulating career, offering both intellectual challenges and the satisfaction of performing work essential to the modern scientific community. It is also apparent that the ISB has at least a dual role to play to facilitate biocurators’ work: (i) to promote biocuration as a career within the greater scientific community; (ii) to aid the development of resources for biomedical research through promotion of nomenclature and data-sharing standards that will allow interconnection of biological databases and better exploit the pivotal contributions that biocurators are making
- …