Cooperative Research Centre

About: Cooperative Research Centre is a based out in . It is known for research contribution in the topics: Population & Sea ice. The organization has 7633 authors who have published 8607 publications receiving 429721 citations.

Using ants as bioindicators in land management: simplifying assessment of ant community responses

Abstract: Summary 1. The indicator qualities of terrestrial invertebrates are widely recognized in the context of detecting ecological change associated with human land-use. However, the use of terrestrial invertebrates as bioindicators remains more a topic of scientific discourse than a part of land-management practice, largely because their inordinate numbers, taxonomic challenges and general unfamiliarity make invertebrates too intimidating for most land-management agencies. Terrestrial invertebrates will not be widely adopted as bioindicators in land management until simple and efficient protocols have been developed that meet the needs of land managers. 2. In Australia, ants are one group of terrestrial insects that has been commonly adopted as bioindicators in land management, and this study examined the reliability of a simplified ant assessment protocol designed to be within the capacity of a wide range of land managers. 3. Ants had previously been surveyed intensively as part of a comprehensive assessment of biodiversity responses to SO 2 emissions from a large copper and lead smelter at Mt Isa in the Australian semi-arid tropics. This intensive ant survey yielded 174 species from 24 genera, and revealed seven key patterns of ant community structure and composition in relation to habitat and SO 2 levels. 4. We tested the extent to which a greatly simplified ant assessment was able to reproduce these results. Our simplified assessment was based on ant ‘bycatch’ from bucket-sized (20-litre) pitfall traps used to sample vertebrates as part of the broader biodiversity survey. We also greatly simplified the sorting of ant morphospecies by considering only large (using a threshold of 4 mm) species, and we reduced sorting time by considering only the presence or absence of species at each site. In this manner, the inclusion of ants in the assessment process required less than 10% of the effort demanded by the intensive ant survey. 5. Our simplified protocol reproduced virtually all the key findings of the intensive survey. This puts effective ant monitoring within the capacity of a wide range of land managers.

Sugar accumulation in grape berries: Cloning of two putative vacuolar invertase cDNAs and their expression in grapevine tissues

Abstract: During grape berry (Vitis vinifera L.) ripening, sucrose transported from the leaves is accumulated in the berry vacuoles as glucose and fructose. To study the involvement of invertase in grape berry ripening, we have cloned two cDNAs (GIN1 and GIN2) from berries. The cDNAs encode translation products that are 62% identical to each other and both appear to be vacuolar forms of invertase. Both genes are expressed in a variety of tissues, including berries, leaves, roots, seeds, and flowers, but the two genes have distinct patterns of expression. In grape berries, hexose accumulation began 8 weeks postflowering and continued until the fruit was ripe at 16 weeks. Invertase activity increased from flowering, was maximal 8 weeks postflowering, and remained constant on a per berry basis throughout ripening. Expression of GIN1 and GIN2 in berries, which was high early in berry development, declined greatly at the commencement of hexose accumulation. The results suggest that although vacuolar invertases are involved in hexose accumulation in grape berries, the expression of the genes and the synthesis of the enzymes precedes the onset of hexose accumulation by some weeks, so other mechanisms must be involved in regulating this process.

The influence of scale and geography on relationships between stream community composition and landscape variables: description and prediction

Abstract: SUMMARY 1 We analysed an existing database of macroinvertebrates and fish in the context of a newly established geographical information system (GIS) of physical features to determine the relationships between stream community composition and physical factors measured at three landscape scales – catchment, reach and bedform Both an exploratory (concordance analysis) and a predictive (ausrivas) approach were used 2 The environmental variables that most successfully accounted for variation in macroinvertebrate assemblages were mainly ‘natural’ and at the catchment-scale (relief ratio, basin diameter, etc) but the human-induced physical setting of percentage of pasture in the riparian zone was also influential For fish, ‘natural’ variables were also dominant, but these were mostly at the bedform or reach scales and land use featured strongly 3 Geographic location accounted for some of the variation in invertebrate assemblages, partly because geography and influential conditions/resources are correlated but also because different species may have evolved in different places and have not colonised every ‘ecologically appropriate’ location Geographic location was not influential in accounting for variation in assemblages of strongly flying invertebrates, supporting the hypothesis that organisms having high dispersal potential can be expected to break down geographic barriers more readily than those with poor dispersal powers In accord with what is known about the local evolution and restricted distributions of native and exotic species, history (reflected in geography) appeared to account for some variation in fish assemblages 4 Given their different mathematical bases, the fact that exploratory and predictive analyses yielded similar results provides added confidence to our conclusions

Coral Community Adaptability to Environmental Change at the Scales of Regions, Reefs and Reef Zones

Abstract: SYNOPSIS. Projected global increases in temperature, sea level, storminess and atmospheric carbon dioxide (CO2) are likely to cause changes in reef coral communities which the present human generation will view as deleterious. It is likely coral community trajectories will be influenced as much by the reduction in intervals between extreme events as the projected increases in means of environmental parameters such as temperature, atmospheric CO2 and sea-level. Depressed calcification rates in corals caused by reduced aragonite saturation state of water may increase vulnerability of corals to storms. Moreover, reduction in intervals between storms and other extreme events causing mass mortality in corals (coral predators, diseases, bleaching) are likely to more frequently “set back” reef coral communities to early successional stages or alternate states characterized by non-calcifying benthos (plants, soft corals, sponges). The greater the area and the longer the duration of dominance of putative “coral/coralline algae” zones of coral reefs by non-calcifying stages, the less will be the reefs capacity to accrete limestone bulk locked up in the big skeletal units of late successional stages (i.e., very large old corals). Averaged over decades to centuries, the effects of such changes on the coral community's carrying capacity for other biota such as fish are unpredictable. A “shifting steady-state mosaic” null model may provide a useful conceptual tool for defining a baseline and tracking changes from that baseline through time.