A hierarchical framework for classifying seabed biodiversity with application to planning and managing Australia’s marine biological resources

A conceptual hierarchical framework for classifying marine biodiversity on the sea floor, used successfully for continental-scale bioregionalisation and adopted to guide marine resource planning and management in Australia, has wider application at a global scale. It differs from existing schemes for classifying marine biota by explicitly recognizing the overarching influence of large-scale biodiversity patterns at realm (ocean basin and tectonic), provincial (palaeohistorical) and bathomic (depth-related) levels. The classification consists of 10 nested levels within realms, of which the first seven are primarily spatially nested and ecosystem based, and the lowest levels represent units of taxonomic inheritance: 1 - provinces, 2 - bathomes, 3 - geomorphological units, 4 - primary biotopes, 5 - secondary biotopes, 6 - biological facies, 7 - micro-communities, 8 - species, 9 - populations, and 10 - genes. According to this scheme, marine biodiversity is characterised in a systematic way that captures the scale-dependence and hierarchical organization of the biota. Levels are defined with respect to their functional roles and spatial scales, in a manner that directly supports the incorporation of biodiversity information in regional-scale planning by highlighting centres of endemism, biodiversity richness and priority information needs. Whereas species are the fundamental units of biodiversity, biological facies are the smallest practical unit for conservation management at regional scales. In applying the framework we make extensive use of biological and physical surrogates because marine data sets, particularly those of the deep sea, are usually sparse and discontinuous. At each level of the hierarchy, attributes and surrogates are defined to reflect the scale and range of biogeographic and ecological processes that determine the spatial and temporal distribution of marine biodiversity. The Australian experience in applying this framework suggests that it provides a workable systematic basis for defining, managing and conserving biodiversity in the sea.     

Experimental suspended culture of mussels (Mytilus edulis L.) in Wales using spat transplanted from a distant settlement ground

Spat of Mytilus edulis L. were transferred 300 km by road on collectors from an area of high and regular spatfall, but unfavourable culture conditions, to a raft at a site deficient in mussel settlement. Spat were collected on coir ropes and fibrous rubberized matting staked to intertidal settlement grounds in Morecambe Bay, northwest England. During January to April, 80 mm circumference ropes could collect 3 000–7 000 spat/m/week, with smaller numbers in other months, and fibrous matting sometimes also caught many spat.Spatted collectors were suspended in the Menai Straits, North Wales. Despite heavy losses from overcrowding, fast currents and turbulence, growth was sufficiently good for some rope populations to produce marketable crops after about 16 months. Mean lengths increased from 1.5–5.0 mm to 47.5 mm in the first year, and to 60 mm after 1.5–2 years. At about 55 mm, attained at ca 16 months, the best crops yielded 10–15 kg/m live weight, corresponding to 2–3 kg of cooked meat/m. Percentage meat yields from 40–50 mm mussels were equally good, suggesting that crops could be harvested below the present marketable size.Economic systems for collecting spat and for on-growing at controlled densities remain to be developed for different hydrographic conditions and scales of commercial operation in Britain.     

The effect of controlling bracken [Pteridium aquilinum (L.) Kuhn] on pasture production

The outcome of spraying two bracken-infested hill sites in July with asulam at the commercial rate of 4·5 kg a.i. per ha was a 98% reduction in frond numbers which persisted for the following 3 years. Broad-leaved grasses, Agrostis tenuis, Agrostis canina and Poa pratensis, were susceptible to asulam and were severely reduced at both sites while fine-leaved grasses, Festuca ovina and Deschampsia flexuosa, were resistant. Over a period of 3 years after spray application the original bare ground under the bracken canopy and that produced by the effects of asulam was recolonized by the recovery of the broad-leaved grasses and an increase in the cover of herbs. The latter also increased on the unsprayed control areas. A favourable aspect and an abundance of the productive broad-leaved grasses appeared to be the main factors which determined the amount of increase in herbage yield observed following spray treatment. One such area gave a herbage DM yield of 3039 kg ha^-1 during the growing season which was 47% greater than the control while an area with a less favourable aspect and dominated by the less productive fine-leaved grasses gave a herbage yield of 2069 kg ha^-1 which was only 18% greater than the control.     

KNOWLEDGE MANAGEMENT FOR LAND DEGRADATION MONITORING AND ASSESSMENT: AN ANALYSIS OF CONTEMPORARY THINKING

It is increasingly recognised that land degradation monitoring and assessment can benefit from incorporating multiple sources of knowledge, using a variety of methods at different scales, including the perspectives of researchers, land managers and other stakeholders. However, the knowledge and methods required to achieve this are often dispersed across individuals and organisations at different levels and locations. Appropriate knowledge management mechanisms are therefore required to more efficiently harness these different sources of knowledge and facilitate their broader dissemination and application. This paper examines what knowledge is, how it is generated and explores how it may be stored, transferred and exchanged between knowledge producers and users before it is applied to monitor and assess land degradation at the local scale. It suggests that knowledge management can also benefit from the development of mechanisms that promote changes in understanding and efficient means of accessing and/or brokering knowledge. Broadly, these processes for knowledge management can (i) help identify and share good practices and build capacity for land degradation monitoring at different scales and in different contexts and (ii) create knowledge networks to share lessons learned and monitoring data among and between different stakeholders, scales and locations. Copyright © 2011 John Wiley & Sons, Ltd.