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Long-term Monitoring Programme (long-term + monitoring_programme)
Selected AbstractsDifferences in benthic cover inside and outside marine protected areas on the Great Barrier Reef: influence of protection or disturbance history?AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009Monique R. Myers Abstract 1.Marine protected areas (MPAs) are being used increasingly to manage and protect marine resources. Most studies of MPAs have focused on fish. In this study, the influence of MPA protection on coral reef benthic organisms on the Great Barrier Reef (GBR) was investigated. In addition, the interaction between protection and natural disturbance history was examined. 2.Differences in benthic cover inside and outside MPAs were assessed at 15 pairs of Protected and General Use reefs on the GBR using annual monitoring data from the Australian Institute of Marine Science's Long-Term Monitoring Programme (LTMP). At each reef, benthic cover was determined using a benthic video survey at three sites, with each site consisting of five 50,m transect lines separated by at least 250,m running parallel to the reef crest at 6,9,m depth. 3.Benthic cover was related to both protection status and disturbance history, but natural perturbations exerted a stronger influence on benthic cover than did protection status. The influence of natural perturbation was most noticeable for hard coral. 4.Most reefs where no natural disturbance events had occurred (,undisturbed reefs') had higher hard coral cover and lower soft coral cover than General Use reefs. While the high levels of hard coral on Protected reefs may be a result of protection status, it might also have resulted from selection bias that occurred during the initial zoning of the Great Barrier Reef Marine Park (i.e. managers may have given protection status to reefs with high coral cover). 5.These results are likely influenced by the relatively low intensity of human use, both on the Great Barrier Reef in general and at the particular monitoring sites studied. Over time, as local populations and tourism increase, the effect of protection may become more evident at LTMP sites. Copyright © 2009 John Wiley & Sons, Ltd. [source] Bycatch in a tropical schooling , penaeid fishery and comparisons with a related, specialised trawl regimeFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2009Q. DELL Abstract, The bycatch in a tropical Australian banana prawn, Penaeus merguiensis (de Man), fishery is described and contrasted with the closely related tiger prawn, Penaeus semisulcatus De Haan and Penaeus esculentus Haswell, fishery. Most of the similarity between banana prawn fishery catches was accounted for by three teleost species constituting 51.4% of the total bycatch weight. The bycatch assemblage structure of this fishery was significantly different (P < 0.05) from the adjoining tiger prawn fishery. The banana prawn fishery had a higher mean bycatch catch rate from shorter duration trawls, but lower estimated total annual bycatch (1502 t yr,1) than the longer duration trawls of the tiger prawn fishery (20 073 t yr,1). This study provides new data for quantifying bycatch and improving the accuracy of quantitative risk assessments currently being used to demonstrate sustainability of bycatch populations. The information will be incorporated into collaborative development of a long-term monitoring programme. [source] The development of sustainable earthworm populations at Calvert landfill site, UKLAND DEGRADATION AND DEVELOPMENT, Issue 1 2004K. R. Butt Abstract Earthworms Allolobophora chlorotica and Aporrectodea longa were inoculated into Calvert landfill site in spring 1992, in conjunction with the planting of two tree species Alnus glutinosa and Acer pseudoplatanus. Monitoring has taken place over a period of 11 years. Sampling in 2003 revealed that earthworm distribution no longer equated to the inoculation treatments; the worms had spread extensively. The presence of A. glutinosa had a significant effect (p<0,01) on earthworm number (mean density 198,m,2) and biomass (34,g,m,2) compared to plots where A. pseudoplatanus had been planted and subsequently died (mean density 118,m,2; biomass 21,g,m,2). Results suggest that tree presence may be critical to earthworm community development. In 2002, the spread of A. chlorotica from the original points of inoculation had reached 60,m with the highest recorded population density at 108,m,2 with a mass of 18,6,g,m,2. A. longa was recorded at a distance of 132,m from the nearest point of inoculation with the highest recorded population density at 70,m,2 with a mass of 49,3,g,m,2, 10,m from the original inoculation grid. Other species recorded (and % of total) were Aporrectodea rosea (0,9) Lumbricus castaneus (7,4), Eiseniella tetraedra (21,5) and Lumbricus rubellus (4,5). The two inoculated species, A. chlorotica (40,4) and A. longa (25,3), accounted for two thirds of the earthworms found on site. The highest earthworm community density was 213,m,2 with a mass of 73,9,g,m,2 at 10,m from original point of inoculation. In 1999, treatments of surface organic matter (OM), in the form of composted green waste, and rotavation were applied to non-replicated plots of 50,m2 with the effects on earthworm distribution and abundance recorded in 2002. Addition of OM alone led to an increase in number and mass (331,m,2; 95,g,m,2) compared to the control (233,m,2; 51,g,m,2), while rotavation alone (111,m,2; 36,g,m,2) had a detrimental effect over the given time period. This long-term monitoring programme has demonstrated the development of sustainable earthworm communities on a landfill site. Natural nutrient accumulation and addition of OM on or into the soil-forming material appeared to assist this process. This work may help to inform post-capping treatment at similar landfill sites Copyright © 2004 John Wiley & Sons, Ltd. [source] Variability in active galactic nuclei: confrontation of models with observationsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2002M.R.S. Hawkins The variability of active galactic nuclei (AGN) has long held the promise of shedding light on their detailed structure, and possibly other astrophysical phenomena. Different emission mechanisms lead to different patterns of variability in flux, which are in principle easily distinguishable. Recent predictions for the expected spectrum of variations for various models are now in such a form that they can be compared with the observed statistical properties of AGN light curves from large-scale monitoring programmes. In this paper, we use the results of a long-term monitoring programme of a large sample of quasars and Seyfert galaxies, as well as individual light curves from the literature, to distinguish between the various model predictions. The results favour a model based on accretion disc instability over the starburst model, where the variation comes from a succession of supernova bursts, but it also appears that much of the observed variation in quasars is due to gravitational microlensing. [source] Making the biodiversity monitoring system sustainable: Design issues for large-scale monitoring systemsAUSTRAL ECOLOGY, Issue 1 2004IAN WATSON Abstract There is strong demand for information about the status of, and trends in, Australia's biodiversity. Almost inevitably, this demand for information has led to demand for a broad-scale monitoring system. However, the decision to embark on a monitoring system should only be made once it has been established that a monitoring system is the optimal way to inform management. We stress the need to invest resources in assessing whether a monitoring system is necessary before committing resources to the design and implementation of the system. Current debate associated with the design of a biodiversity monitoring system has similarities to the debate within the range management profession in the early 1970s. The experience with range monitoring shows that large-scale monitoring systems such as those being proposed will require considerable resources, recurrently expended into the distant future, but with only a limited ability to adapt to new demands. Those involved in any biodiversity monitoring system will need to understand the implications of investing in a long-term monitoring programme. Monitoring sustainability will only be possible if the monitoring system is itself sustainable. We discuss a number of issues that need to be addressed before the system is at all sustainable. These attributes are a mix of biophysical, social and institutional attributes and highlight the view that monitoring systems of the type being suggested comprise an unusual mixture of attributes not found in typical scientific activity. The present paper is not a technical manual, but rather considers some of the design issues associated with designing and implementing large-scale monitoring systems. [source] Phosphorus decrease and climate variability: mediators of synchrony in phytoplankton changes among European peri-alpine lakesFRESHWATER BIOLOGY, Issue 10 2005ORLANE ANNEVILLE Summary 1. In an attempt to discern long-term regional patterns in phytoplankton community composition we analysed data from five deep peri-alpine lake basins that have been included in long-term monitoring programmes since the beginning of the 1970s. Local management measures have led to synchronous declines in phosphorus concentrations by more than 50% in all four lakes. Their trophic state now ranges from mesotrophic to oligotrophic. 2. No coherence in phytoplankton biomass was observed among lakes, or any significant decrease in response to phosphorus (P)-reduction (oligotrophication), except in Lakes Constance and Walen. 3. Multivariate analyses identified long-term changes in phytoplankton composition, which occurred coherently in all lakes despite the differing absolute phosphorus concentrations. 4. In all lakes, the phytoplankton species benefiting from oligotrophication included mixotrophic species and/or species indicative of oligo-mesotrophic conditions. 5. A major change in community composition occurred in all lakes at the end of the 1980s. During this period there was also a major shift in climatic conditions during winter and early spring, suggesting an impact of climatic factors. 6. Our results provide evidence that synchronous long-term changes in geographically separated phytoplankton communities may occur even when overall biomass changes are not synchronous. [source] | |||||||||||||