The need for clear and comparable terminology in benthic ecology. Part II. Application of the European Directives

• 1. Problems with the classification system for marine ‘habitats’ are highlighted, which, ideally, should combine both comprehensibility and scientific rigour, being neither too simplistic nor so complicated that the system is accessible to only a few experts.
• 2. The European Union's Habitats Directive has created multiple difficulties owing to the varied interpretations of the different European Community members trying to apply it. The problem is even more complex in the marine domain, where the difficulty of application has been greatly underestimated.
• 3. Several areas for future applied research in the field of benthic ecology are proposed.

Copyright © 2007 John Wiley & Sons, Ltd.     

镇赉高产塘的底栖动物及其利用率

自１９８８年至１９９０年，在吉林省镇赉渔场高产地中，先后应用了定性、定量采集，地底铺网、昆虫挂网等手段，得出在集约化养鲤池中，鲤对水蚯蚓的利用率为现存量的４８％至７３．７％，平均约６１％左右。摇蚊科幼虫的区系季节变化，一年中有两个高峰期，其羽化率为现存量的２８．９７％至４７．５７％，平均４１．６％左右。鲤对摇蚊科幼虫的利用率为现存量的３５％到６７％，平均５０％左右。     

Invasive Asian clam distribution pattern reveals minimal constraints to downstream dispersal and imperceptible ecological impacts

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Effectiveness of acoustic cameras as tools for assessing biogenic structures formed by Sabellaria in highly turbid environments

1. Accurately mapping the extent and status of biogenic reefs formed by polychaete worms of the genus Sabellaria is of conservation importance given their protected status across Europe.
2. Traditionally, side‐scan sonar (SSS) combined with ground‐truthing in the form of seabed photography and videography has been widely accepted as the most suitable approach for mapping these reefs in the subtidal zone. In highly turbid environments visibility at the seabed can be near zero, however, rendering optical‐based ground‐truthing redundant. Consequently, the true distribution and status of Sabellaria reefs in some shallow subtidal areas around the UK remains unclear despite their designation as Annex‐I features of several Special Areas of Conservation (SACs) under the Habitats Directive.
3. Acoustic camera imagery (ACI) collected using acoustic cameras in two deployment configurations matched well with the backscatter signatures of seabed features in corresponding SSS data. The ACI was of suitable resolution for visualizing Sabellaria colony structures, allowing for their Annex‐I ‘reef’ defining attributes (extent, patchiness, and elevation) to be assessed. Colony formation ‘type’ was also distinguishable in the ACI, although confidence in differentiating between low‐lying Sabellaria formations and surrounding substrates was low, particularly when using a pole‐mounted configuration.
4. This study provides a proof of concept for using acoustic cameras as tools for ground‐truthing SSS interpretation and assessing the status of Sabellaria bioconstructions in low‐visibility environments. Further development of this approach and incorporating it into statutory monitoring programmes could improve the management of the reef habitats in subtidal areas of the Severn Estuary and other highly turbid environments.

     

Complexity of river ciliate communities at a national park highlights the need for microbial conservation

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Identification of microsatellite loci and examination of genetic structure for the endangered springsnails Juturnia kosteri and Pyrgulopsis roswellensis in the Chihuahuan Desert

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Sediment organic carbon integrates changing environmental conditions to predict benthic assemblages in shallow Arctic seas

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Assessing the effectiveness of restoration actions for Bryozoans: The case of the Mediterranean Pentapora fascialis

1. Marine ecosystems are highly affected by several human stressors. In this context, beyond passive restoration measures such as the creation of marine protected areas, it is urgent that we explore active restoration measures to enhance and accelerate the recovery of sessile marine species.
2. Bryozoans are among the most common sessile invertebrates in rocky bottom ecosystems and are considered habitat‐forming species that are highly vulnerable to physical disturbances, such as recreational diving, ghost fishing nets, and global warming, which makes them highly vulnerable to other impacts. Despite their ecological importance and vulnerability, to date restoration actions for bryozoans have rarely been explored.
3. In this study, different restoration techniques were developed and tested, with a focus on two types of effective methodologies previously applied to other marine invertebrates: recruitment enhancement and the transplantation of adult colonies, in both cases using the Mediterranean bryozoan Pentapora fascialis as a model species.
4. First, different types of artificial surfaces were installed in different coralligenous habitats to test the enhancement of recruitment, concluding that plastic grids are the best substrate in terms of facilitating the recruitment of new bryozoan colonies.
5. Second, different methodologies were tested for adult transplantation. The most successful was to fix colonies to a suitable substrate with a nylon thread attached to the colony ex situ (i.e. on the boat).
6. Using this technique a trial restoration programme was undertaken, involving transplanting adult colonies collected from a ghost fishing net trapped on the bottom, which showed a high survival rate of ~50% after 6 months.
7. The low economic cost of the implementation of the proposed techniques as well as the successful results obtained highlight the viability of restoring bryozoan populations over long temporal and spatial scales.