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Bugs beneath the surface： the functional significance of soil macroinvertebrates to landscape health in Australia＇s tropical savannas

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Insect Science 2005年第4期12卷 307-312页

作者： TRACY ZOE DAWES-GROMADZKI csiro sustainable ecosystems and Tropical Savannas Cooperative Research Centre Australia

Soil macroinvertebrates play an important role in sustaining production and biodiversity in Australia＇ s tropical savannas. For example, termites, through their foraging and nesting activities, recycle nutrients and carbon and produce soil pores that facilitate water infiltration. The challenge ahead is to quantitatively understand the relationships and processes that drive this. What roles do different species and functional groups of macroinvertebrates play in various landscape processes？ What are the effects of different land management practices （e.g., domestic cattle grazing, fire） on these relationships, and the consequences for landscape health？ This paper presents preliminary results from studies in northern Australia, that examine the effects of land condition and domestic cattle grazing on soil macroinvertebrates, and the potential for termites to be used as a tool to restore soil function in degraded areas. In northern Australia, increased degradation seems to be associated with declines in the diversity and activity of macroinvertebrates. Termites appear to be one of the most resilient groups, with some species capable of maintaining activity in degraded landscapes.

关键词： Australia landscape health land management soil function soil macroinvertebrates tropical savanna

Farmers’knowledge,attitudes,and practices with respect to rodent management in the upland and lowland farming systems of the Lao People’s Democratic Republic

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Integrative Zoology 2007年第3期2卷 165-173页

作者： Peter R.BROWN Khamouane KHAMPHOUKEO csiro sustainable ecosystems CanberraAustralian Capital TerritoryAustralia National Agricultural and Forestry Research Institute VientianeLao PDR

Rodents are a serious constraint to poor farmers in the upland and lowland farming systems of the Lao People’sDemocratic Republic and have been described as the pest they have least control over. To better understand theseproblems a baseline survey of farmers was conducted to assess their knowledge, attitudes, and practices with respectto rodent management. A structured survey was conducted in 12 villages across Luang Namtha, Luang Prabang,and Houaphan provinces. Twenty farmers from each village were interviewed (a total of 240 farmers). Farmersnoted that the main factor limiting production was pests (70%), with rats identified as the most important pest(98%). The mean yield loss was estimated at 19% (range 0–100%). Trapping and rodenticides were commonlyused by farmers. Farmers believed that it was important to control rats and believed that rats could only be controlledif farmers worked together. However, 65% of farmers conducted rodent control by themselves, and 92% offarmers believed that rodenticides were harmful to the environment. The main constraints identified were the highcost of some control methods and the need to get farmers to work together as a community.

关键词： decision making farmers’beliefs pest rice rodent management upland crop

Influences of Shrinkage,Creep,and Temperature on the Load Distributions in Reinforced Concrete Buildings During Construction

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Tsinghua Science and Technology 2009年第6期14卷 756-764页

作者：方东平席海峰王晓明张传敏 School of Civil Engineering Tsinghua University Urban Systems Program CSIRO Sustainable EcosystemsCommonwealth Scientific and Industrial Research Organisation(CSIRO) Henan Development and Reform Commission

Site measurements have shown that slab loads re-distribute, between the slabs during the concrete curing, while the external Ioadings and structural geometry remain the same. Some have assumed that this is caused by concrete shrinkage and creep, but there have been no studies on how these factors exactly influence the load distributions and to what degree these influences exist. This paper analyzes the influences of concrete shrinkage, creep, and temperature on the load re-distributions among slabs. Although these factors may all lead to load re-distribution, the results show that the influence of concrete shrinkage can be neglected. Simulations indicate that shrinkage only reduces slab loads by a maximum of 1.1%. Creep, however, may reduce the maximum slab load by from 3% to 16% for common construction schemes. More importantly, temperature variations between day and night can cause load fluctuation as large as 31.6%. This analysis can, therefore, assist site engineers to more accurately estimate slab loads for construction planning.

关键词： reinforced concrete buildings construction load re-distribution structural characteristic parameter slab-shore interaction shrinkage creep and temperature

Fluctuating resources,disturbance and plant strategies:diverse mechanisms underlying plant invasions

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Journal of Arid Land 2013年第3期5卷 284-297页

作者： Ian J RADFORD csiro sustainable ecosystems Davies LaboratoryPrivate Mailbag POAitkenvale 4814Australia Botany Department University of OtagoPO Box 56Dunedin 9054New Zealand

This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. （2000）. I measured relative functional responses of both invasive and native plants to changed resource availability due to nutrient enrichment and rainfall, and to increased disturbance. Data are presented from studies in two contrasting ecosystems. First is a series of glasshouse and field experiments on the invader Hieracium lepidulum and associated invasive and native species in subalpine temperate New Zealand. Second is a field study of invasive and native plant responses to altered disturbance regimes and rainfall from tropical savannas of north eastern Australia. Invaders responded differently from native species to changes in resource availability in both subalpine and tropical studies. However, invaders differed among themselves showing that different species exploit different functional niches to invade their respective habitats. These findings contribute to the contention that the fluctuating resource hypothesis does not provide a universal explanation for plant invasions. The diverse functional responses to increased resource availability among invaders in this and previous studies suggest that the cause of invasion depends on unique combinations of habitat and functional attributes of invaders and native assemblages. Such findings imply that universal predictions of what will happen under climate change scenarios across the globe will be difficult to make.

关键词： plant invasion plant strategies C-S-R triangle fluctuating resources disturbance

Speed-up Multi-modal Near Duplicate Image Detection

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Open Journal of Applied Sciences 2013年第1期3卷 16-21页

作者： Chunlei Yang Jinye Peng Jianping Fan 1csiro sustainable ecosystems Carmody Road St. Lucia Queensland Australia 2CSIRO Sustainable Ecosystems Highett Australia csiro sustainable ecosystems Highett Australia

Near-duplicate image detection is a necessary operation to refine image search results for efficient user exploration. The existences of large amounts of near duplicates require fast and accurate automatic near-duplicate detection methods. We have designed a coarse-to-fine near duplicate detection framework to speed-up the process and a multi-modal integra-tion scheme for accurate detection. The duplicate pairs are detected with both global feature (partition based color his-togram) and local feature (CPAM and SIFT Bag-of-Word model). The experiment results on large scale data set proved the effectiveness of the proposed design.

关键词： Near-Duplicate Detection Coarse-To-Fine Framework Multi-Modal Feature Integration

Load Distribution Assessment of Reinforced Concrete Buildings During Construction with Structural Characteristic Parameter Approach

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Tsinghua Science and Technology 2009年第6期14卷 746-755页

作者：方东平席海峰王晓明张传敏赵挺生 School of Civil Engineering Tsinghua University Urban Systems Program CSIRO Sustainable EcosystemsCommonwealth Scientific and Industrial Research Organisation(CSIRO) Henan Development and Reform Commission School of Civil Engineering and Mechanics Huazhong University of Science and Technology

High-rise reinforced concrete buildings are in great demand in developing countries with rapid urbanization. Construction engineers are facing more and more safety control challenges. One major issue is the understanding of the load distributions, especially the maximum slab load, of structures under construction, which is time dependent. Previous methods were mainly targeted to specific examples, providing specific solutions without addressing the fundamental issues of finding general solutions for load distributions in reinforced concrete buildings with different geometrical and material characteristics during construction. The concept of a structural characteristic parameter is used here to parametedze the main geometrical and material characteristics of concrete structures for generalized assessments of load distributions during construction. The maximum slab load for 20 different construction shoring/reshoring schemes is presented. The results indicate that the traditional simplified method may underestimate or overestimate the maximum slab load, depending mainly on the shoring/reshoring schemes. The structural characteristic parameter approach was specifically developed to assist construction engineers to estimate load distributions to assure safe construction procedures.

关键词： reinforced concrete buildings construction load re-distdbution structural characteristic parameter: slab-shore interaction

An assessment of response of soil-based indicators to nitrogen fertilizer across four tropical eucalyptus plantations

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Journal of Forestry Research 2009年第3期20卷 237-242,286页

作者： D.S.Mendham S.Kumaraswamy K.V.Sankaran K.Smitha John T.S.Grove A.M.O’Connell S.J.Rance M.P.Sujatha csiro sustainable ecosystems Kerala Forest Research Institute

Low nitrogen (N) availability often results in reduced productivity of Eucalyptus plantations. We studied the response of four eucalyptus plantations (two plantations of E. tereticornis on the coastal lowlands, and two plantations of E. grandis in the upland region of the Western Ghats, Kerala, India) to N addition and related this response to seasonal N mineralization as well as other indices of N availability, in order to examine the utility of soil based indicators of N mineralization for predicting the response of eucalyptus growth to added N fertilizer. Several biochemical indicators were examined for their capacity to predict response to N fertilizer, including total soil N, soil C:N ratio, and N released during anaerobic and aerobic incubation. Results show that nitrogen fertilizer addition increased productivity across the 4 sites from 7% to 70%, N released during an aerobic incubation had the highest correlation with fertilizer response across the 4 sites (R2=0.92, p<0.01), and that Modelled seasonal soil N mineralisation was a poorer predictor of fertilizer response than N released during an aerobic incubation. Whilst some of these indicators are promising, they need wider validation and testing before they could be routinely applied.

关键词： nitrogen mineralization Eucalyptus grandis Eucalyptus tereticornis N fertilization site management productivity improvement

The use of faecal NIRS to monitor diet quality different grazing systems in tropical savannas

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The use of faecal NIRS to monitor diet quality different gra...

Taxonomic confusion of two tramp ant species： Iridomyrmex anceps and Ochetellus glaber are really species complexes

ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： A.White L.P.Hunt S.R.Petty D.P.Poppi Heytesbury Beef University of Queensland csiro sustainable ecosystems

＜正＞Introduction Nutrition is the major factor influencing animal production in grazing systems,however it is very difficult to monitor in extensive *** is especially so in northern Australia which has distinct wet and dry seasons,large paddocks with highly heterogeneous pastures and the likelihood for selective *** NIRS is one method to monitor diet quality in these extensive systems（Givens et al.,1997）.Here we present data that illustrates the considerable seasonal differences in nutrition across four different grazing systems and discuss this in relation to collection methods and inter-animal variation that occurs.

关键词： animal nutrition NIRS tropical savannas grazing systems

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Current Zoology 2011年第5期57卷 662-667页

作者： Benjamin D. HOFFMANN Alan N. ANDERSEN Xiang ZHANG csiro Ecosystem Sciences Tropical Ecosystems Research Centre PMB 44 Winnellie NT 0822 Australia College of Plant Protection Fujian Agriculture and Forestry University Fuzhou Fujian 350002 China

Many invasive invertebrates belong to unresolved species complexes, and have a history of misidentification and in-appropriate management. Here we detail confusion surrounding the taxonomy and identification of two dolichoderine ant species, Iridomyrmex anceps Roger and OcheteUus glaber Mayr, which are commonly cited in the literature as having been spread widely by human commerce. We provide morphometric data and images strongly suggesting that these two ＂species＂ are instead com- plexes of species that are likely native to many regions where they are purportedly introduced. We take particular interest in the status of species referred to as L anceps and O. glaber in China, as this is the most northerly distribution of both genera. We con-clude by suggesting that many identifications of both species are likely to be unreliable, and we recommend against any manage- ment action aimed at controlling these species under the assumption that they are exotic [Current Zoology 57 （5）： 662-667, 2011].

关键词： Ant Exotic Invasive Invertebrate Management Tramp ant