Developing a habitat classification typology for subtidal habitats in a temperate estuary in New South Wales, Australia

2016 ◽  
Vol 67 (8) ◽  
pp. 1186 ◽  
Author(s):  
Tom R. Davis ◽  
David Harasti ◽  
Stephen D. A. Smith

Effective estuarine management depends on adequate data about the ecology, extent and biodiversity of component habitats. However, these data are often scant, as exemplified by the Port Stephens estuary, part of the Port Stephens–Great Lakes Marine Park (NSW, Australia), for which even basic descriptions of habitat types and extent are lacking. Herein we present the results of the first quantitative assessment of subtidal benthic communities within the estuary, involving 130km of towed video transects over an area exceeding 50km2. We identified previously undocumented macroalgae-dominated habitat types and found strong correlations between habitat types and depth. The soft coral Dendronephthya australis habitat is of particular interest because this was found to occur exclusively outside current sanctuary (no take) zones. The habitat map of Port Stephens generated during the study provides the basis for more objective representative planning in future iterations of zoning in the estuarine section of the marine park. The study also suggests that depth may be a useful proxy for estuarine habitat types where specific data are lacking. The classification methodology developed during the study was cost-effective, generated robust data and consequently has potential for wider application in other large estuarine bays.

2007 ◽  
Vol 58 (9) ◽  
pp. 843 ◽  
Author(s):  
Kathryn L. Newton ◽  
Bob Creese ◽  
David Raftos

Spatial and temporal patterns of variability in ascidian assemblages were investigated on horizontal subtidal rocky reefs at Port Stephens, New South Wales (NSW). The study was designed to provide a baseline dataset on ascidian diversity and distribution patterns for an area destined to become a marine park (the Port Stephens–Great Lakes Marine Park: PSGLMP). Differences in ascidian assemblages between exposed oceanic island reefs and sheltered reefs within Port Stephens, and between two depth zones within each subtidal reef, were quantified using non-parametric multivariate techniques coupled with analysis of variance (ANOVA). Ascidian assemblages were highly variable between reef sites, reef exposures and particularly between depth zones within each reef surveyed. However, temporal variation was only observed for a few ascidian species. These highly variable spatial patterns in diversity indicate that numerous subtidal reefs may need to be protected within PSGLMP if the aim of the marine park is to adequately represent the entire array of marine biodiversity in the area.


2000 ◽  
Vol 51 (1) ◽  
pp. 81 ◽  
Author(s):  
N. H. de Jong

This study investigated planting techniques and natural regeneration of indigenous woody species within degraded wet meadow wetland at Coomonderry Swamp. Planting tubestock directly into existing vegetation was practical and cost-effective. Clearing of plots allowed infiltration of weeds, early growth of tubestock was inhibited, acid sulfate soils were exposed, and open inundated plots were choked by algae. After four years, Melaleuca ericifolia and Melaleuca linariifolia showed good survivorship at upper and lower elevations. Eucalyptus robusta and Casuarina glauca were more successful at upper elevations, and Leptospermum juniperinum did not succeed at either elevation. These results corresponded to patterns of regeneration and to distributions within undisturbed stands. Despite the evidence of natural regeneration, direct seeding was not successful at the experimental site. Given that poor dispersal was indicated at Coomonderry Swamp, it is unlikely that isolated wetlands in the region could rely solely on seed dispersal for woody revegetation. Even where regeneration can occur naturally, some planting or culling might be required if the desired outcome is a species mix comparable to that observed on undisturbed margins.


1987 ◽  
Vol 2 (3) ◽  
pp. 179-183 ◽  
Author(s):  
S. C. Laufmann

AbstractKnowledge-based System (KBS) technologies have been applied to a variety of knowledge-related tasks with varying degrees of success. Differentiating among classes of knowledge-related tasks, based on the amounts of problem-solving knowledge and case-specific data involved, can provide valuable insight into why this occurs. Based on this comparison, four classes of problems are described. One class, of data-intensive tasks, includes problem types that are difficult or impossible for humans to perform, yet may be solved in a cost-effective manner using currently accessible KBS technology. The characteristic features of problems in this class are given, together with an example of a successfully fielded knowledge-based system that solves a problem from this class.


1970 ◽  
Vol 10 (43) ◽  
pp. 196
Author(s):  
WM McArthur ◽  
K Spencer

A scheme is proposed as a basis for soil fertility studies in areas where little information is available. The first stage consists of sampling the area on a grid and determining the patterns of variation in the status of those nutrient elements likely to be deficient. These patterns are then compared with intensity patterns of environmental (including edaphic) variables. Where the two sets of variables can be quantified, regression analysis may be used to estimate the closeness of the relationship ; otherwise the relationship must be assessed visually from the degree of conformity between patterns. Those environmental variables that relate, causally or otherwise, to the distribution of components of chemical fertility are identified by strong correlations. Information so gained may be used in subsequent agronomic studies, both as a guide to number and location of field plots and as a framework for studies in soil chemistry and pedology. The scheme is illustrated using data derived from studies on the Dorrigo Plateau of New South Wales. Factors relating closely to phosphorus, sulphur, molybdenum, and nitrogen distribution were identified. In no case could one factor be used to predict the adequacy of all nutrients.


1986 ◽  
Vol 26 (3) ◽  
pp. 331 ◽  
Author(s):  
MH Campbell ◽  
MJ Keys ◽  
RD Murison ◽  
JJ Dellow

The effects of time and rate of application of glyphosate, 2,2-DPA and tetrapion on Poa labillardieri and Themeda australis were measured in seven experiments carried out 55 km south of Braidwood, on the southern tablelands of New South Wales between 1980 and 1982. In an eighth experiment (1981) and in a 35-ha demonstration (1983), at the same site, the effects of applying herbicides (before and after the autumn break) and surface-sowing Phalaris aquatica, Festuca arundinacea and Trifiolium repens with fertiliser on the control of P. labillardieri were ascertained. All three herbicides proved effective in reducing the ground cover of P. labillardieri from applications at any time of the year. For T. australis, tetrapion proved effective when applied at any time of the year, while glyphosate and 2,2-DPA were effective in all seasons except winter. Glyphosate at rates between 0.72 and 1.44 kg/ha a.i. was more cost effective than 2,2-DPA (11.1 kg/ha a.i.) and tetrapion (3.75 kg/ha a.i.). Best establishment and development of sown grasses and legumes was attained by applying herbicides after the autumn break but before heavy frosts, and then surface-sowing 1-3 months later. Control of P. labillardieri was best where P. aquatica and F. arundinacea established most densely.


1995 ◽  
Vol 46 (4) ◽  
pp. 715 ◽  
Author(s):  
MP Lincoln Smith ◽  
PMH Hawes ◽  
FJ Duque-Portugal

The nekton of a canal development in NSW, Australia, is described. Two sites each were sampled from the main canal and in end canals. The main canal had more species of fish than did the end canals, but the number of individuals was similar between locations. Abundance of particular species showed three patterns: species that were more abundant in either location, species that varied between locations and sites, and species that did not differ significantly in abundance. There was little evidence that the nekton from the end canals, which are presumably less well flushed, was depauperate compared with the main canal. Surveys of nekton in canal estates should incorporate spatial variability at two or more scales so that the effects of these human developments can be assessed properly.


1981 ◽  
Vol 32 (2) ◽  
pp. 227 ◽  
Author(s):  
SF Rainer ◽  
RC Fitzhardinge

The relationship between spatial patterns in the physical environment and patterns in community and trophic structure in the benthic fauna was investigated in an estuary with periodic deoxygenation of the near- bottom water. Six sites were sampled between intertidal mangroves and an 8 m deep basin of Port Hacking, N.S.W. A total of 163 species was collected, ranging from 11 to 94 at each site. Both frequency and biomass were least in the central basin and highest in a bed of the seagrass Zostera capricorni Aschers. The abundances at these sites encompass the range of values previously recorded for estuaries on the east coast of Australia. The dominant species differed from those reported from other New South Wales estuaries, although the same species were usually present. The distribution of common species was limited by fluctuations in dissolved oxygen levels, but not obviously so by sediment differences or short-term fluctuations in water temperature or salinity. Frequency-based diversity and evenness values were similar to those from other estuarine areas. Biomass-based values were lower at most sites than frequency-based values. Patterns of diversity and evenness could not be simply interpreted as indicators of environmental harshness in the community.


2009 ◽  
Vol 15 (4) ◽  
pp. 238 ◽  
Author(s):  
Judit K. Szabo ◽  
Sue V. Briggs ◽  
Rachel Lonie ◽  
Linda Bell ◽  
Richard Maloney ◽  
...  

May (2002) estimated that the current rate of extinction of species globally is 100?1000 times background rates. Hence a primary goal of biodiversity management is to bring the rate of extinction back to normal levels. Conservation managers face two interrelated problems: limited time and money, and how to allocate the finite available resources (Bottrill et al. 2008, 2009). In this paper we tackle the second of these problems. Definitions of key terms are in Appendix 1.


2019 ◽  
Vol 59 (2) ◽  
pp. 803
Author(s):  
Abdul Qader ◽  
Jai Kant Pandit

CO2CRC, in collaboration with the University of Melbourne and the University of New South Wales, is testing two novel CO2 capture technologies designed for both on-shore and off-shore natural gas applications in a state-of-the-art experimental capture rig at CO2CRC’s Otway National Research Facility. The goal is to develop robust and compact technology for high pressure natural gas separation over a range of adjusted high CO2 concentrations mimicking various gas field conditions. These technologies would facilitate developing new gas fields to recover methane in a cost-effective manner which is currently uneconomical with conventional technologies. In the first stage of testing, commercially available materials (adsorbents and membranes) were used for benchmarking. Results from both adsorbent and membrane technologies are encouraging with respect to recovery and purity of CO2 and methane with the prospect of commercial application.


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