bluuebunny/crossref_metadata_2025 huggingface dataset:
Task Complexity, Epistemological Beliefs and Metacognitive Calibration: An Exploratory Study
Authors: Stahl Elmar , Pieschl Stephanie , Bromme Rainer
Published: February 2007

This article presents an explorative study, which is part of a comprehensive project to examine the impact of epistemological beliefs on metacognitive calibration during learning processes within a complex hypermedia information system. More specifically, this study investigates: 1) if learners differentiate between tasks of different complexity, and set goals and plan their learning behavior accordingly; and 2) whether such adaptive learning behavior is influenced by their epistemological beliefs. Students ( n = 72) inspected a set of six learning tasks and answered multiple questions derived from the COPES-model of self-regulated learning (Winne & Hadwin, 1998)—e.g., they judged the importance of specific learning strategies for a particular learning task. Furthermore, they filled in inventories measuring their epistemological beliefs. Results confirmed significant relationships between task complexity and epistemological beliefs on the one hand and students' judgments on the other.
When Disaster Strikes, Move Your School Online
Authors: Laprairie Kimberly N. , Hinson Janice M.
Published: February 2007

Hurricanes Katrina and Rita displaced thousands of K-12 students and demonstrated that when K-12 schools close unexpectedly and indefinitely, educational chaos results. Events such as deadly flu outbreaks or bioterrorist attacks will have the same impact on education. These possibilities demonstrate the need for state and local officials to begin taking action to ensure that schooling can continue when it is not feasible for students to attend school in person. The development of online learning communities, first to supplement face-to-face instruction and then as a total online replacement, is an uncomplicated and cost effective way to continue schooling without disrupting the learning process. Basically, schools would move online until it was safe to return to school campuses. This article presents a set of guidelines for establishing the infrastructure needed to develop online learning communities and the types of training and support needed to sustain them.
Effectiveness of Various Enhancement Strategies to Complement Animated Instruction: A Meta-Analytic Assessment
Authors: Lin Huifen , Ching Yu-Hui , Ke Fengfeng , Dwyer Francis
Published: February 2007

Animation of various types has been used increasingly in different disciplines in computer-based learning environments to facilitate achievements of different kinds of learning objectives. However, the result of empirical animation studies has been mixed and mostly discouraging. The purpose of this meta-analysis was to examine the instructional effectiveness of different types of enhancement strategies used to complement animated instruction. Eleven hundred and twenty-four college-level students participated in 12 independent experimental studies. The uniqueness of this meta-analysis lies in the fact that the instructional content and four independent criterion measures were held constant in all studies. One hundred and twenty-four effect sizes were calculated. The results indicate that when “conventional” one dimensional animation strategies are employed to complement animated instruction, small to moderate effect sizes are realized and that the various enhancement strategies were not equally effective in facilitating different types of educational objectives.
How Close Have Universal Health Systems Come to Achieving Equity in Use of Curative Services? A Systematic Review
Authors: Hanratty Barbara , Zhang Tuohong , Whitehead Margaret
Published: February 2007

Most governments in established market economies have developed universal systems of health care, but these are being increasingly threatened by widespread health sector reforms. Hence, it is more important than ever to monitor the effects of policy changes on the ability of universal systems to achieve their equity goals. This article provides evidence for such monitoring. The authors present the results of a systematic review of equity in use of curative health services in universal systems, together with a critical appraisal of the essential components of studies to address this question. Of the 79 studies identified that addressed the review question, only 26 met the inclusion criteria and adjusted for differential health need across socioeconomic groups. The authors found a pro-rich bias in use of specialist hospital services and a reasonably equitable access to primary health care by different socioeconomic groups. There was a wide inter-study variation in the difference in utilization rates between people of high and low socioeconomic groups. Improvements are needed in the way that equity in universal systems is monitored, with particular attention to how “need” is defined and to the impact on patients of indirect costs.
Untangling the Confounding Perceptions regarding the Stand Alone it Course
Authors: Wang Yu-Mei , Chen Victor Der-Thanq
Published: February 2007

The stand alone IT/computer course is the earliest IT training model in teacher education|programs. This course model has been severely criticized and there has been a call to eliminate it from preservice teachers' IT training. Over the past decade, new IT initiatives were implemented to integrate the computer use throughout teacher training courses (integrated model) and to promote field-based IT training (field-based model). Overshadowed by new IT initiatives, confounding issues surrounding the stand alone IT course have seldom been brought to the forefront for discussion. The purpose of this article is to review, discuss, and clarify these confounding issues to help teacher educators make evidence-based decisions regarding the stand alone IT course. The authors of this article take the position that the three major IT training models (stand alone, integrated, and field-based) should be viewed as a learning continuum. Efforts should be placed on coordinating the three models so that they complement and support each other.
Implementing Web-Based Intelligent Tutoring Systems in K-12 Settings: A Case Study on Approach and Challenges
Authors: Wijekumar K. K.
Published: February 2007

Technologies for learning environments are a vital and growing market for software development and utilization. A team of designers and developers created a Web-based intelligent tutoring system to teach a reading comprehension strategy for elementary and middle school students. Our approach to designing ITSS. combined the waterfall method of technology design with prescriptions for creating cognitive tutors. This article reports on each phase of the process: analysis, design, development, and implementation of the system and the challenges and solutions at each stage.
Ambipolar Conductive 2,7‐Carbazole Derivatives for Electroluminescent Devices
Authors: Shen J.‐Y. , Yang X.‐L. , Huang T.‐H. , Lin J. T. , Ke T.‐H. , Chen L.‐Y. , Wu C.‐C. , Yeh M.‐C. P.
Published: February 2007

A series of 2,7‐disubstituted carbazole (2,7‐carb) derivatives incorporating arylamines at the 2 and 7 positions are synthesized via palladium‐catalyzed C–N or C–C bond formation. These compounds possess glass transition temperatures ranging from 87 to 217 °C and exhibit good thermal stabilities, with thermal decomposition temperatures ranging from 388 to 480 °C. They are fluorescent and emit in the purple‐blue to orange region. Two types of organic light emitting diodes (OLEDs) were constructed from these compounds: (I) indium tin oxide (ITO)/2,7‐carb (40 nm)/1,3,5‐tris(N‐phenylbenzimidazol‐2‐yl)benzene (TPBI, 40 nm)/Mg:Ag; and (II) ITO/2,7‐carb (40 nm)/tris(8‐hydroxyquinoline) aluminum (Alq3, 40 nm)/Mg:Ag. In type I devices, the 2,7‐disubstituted carbazoles function as both hole‐transporting and emitting material. In type II devices, light is emitted from either the 2,7‐disubstituted carbazole layer or Alq3. The devices appear to have a better performance compared to devices fabricated with their 3,6‐disubstituted carbazole congeners. Some of the new compounds exhibit ambipolar conductive behavior, with hole and electron mobilities up to 10–4 cm2 V–1 s–1.
Neocortical hyperexcitability in a human case of tuberous sclerosis complex and mice lacking neuronal expression of TSC1
Authors: Wang Yanling , Greenwood Joel S. F. , Calcagnotto Maria Elisa , Kirsch Heidi E. , Barbaro Nicholas M. , Baraban Scott C.
Published: February 2007

Objective

To identify brain regions, cell types, or both that generate abnormal electrical discharge in tuberous sclerosis complex (TSC). Here we examined excitatory and inhibitory synaptic currents in human tissue samples obtained from a TSC patient with no discernible cortical tubers and acute neocortical brain slices from a mouse featuring synapsin‐driven conditional deletion of a TSC1 gene. These studies were designed to assess whether TSC gene inactivation alters excitability.

Methods

We used visualized patch‐clamp (human and mouse) and extracellular field (mouse) recordings. Additional mice were processed for immunohistochemistry or Western blot analysis.

Results

Detailed anatomic studies in brain tissue sections from synapsin‐TSC1 conditional knock‐out mice failed to uncover gross anatomic defects, loss of lamination, or frank tuber formation. However, regions of abnormal and potentially activated neocortex were shown using antibodies to nonphosphorylated neurofilaments (SMI‐311) and immediate early genes (c‐Fos). Extracellular recordings from neocortical slices, examining synaptic activity in these regions, demonstrated clear differences in excitability between conditional knock‐out and age‐matched control mice. Whole‐cell patch‐clamp recordings demonstrated excitatory synaptic currents with strikingly long duration and epileptiform discharge patterns, similar to waveforms observed in our human tissue samples. These events were 1‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionate (AMPA) receptor mediated and were most prominent in neocortex. Normal‐appearing inhibitory postsynaptic currents (human) and intrinsic neuronal firing patterns (mouse) were also recorded.

Interpretation

This combination of human and mouse tissue studies suggests, for the first time, that synaptic excitation is altered in a direction that favors seizure generation in TSC brain tissue regardless of cortical tubers. Ann Neurol 2007
Magnetische Nanopartikel: Synthese, Stabilisierung, Funktionalisierung und Anwendung
Authors: Lu An‐Hui , Salabas Elena Lorena , Schüth Ferdi
Published: February 2007

Dieser Aufsatz beschreibt die Synthese, Stabilisierung, Funktionalisierung und Anwendung magnetischer Nanopartikel sowie die magnetischen Eigenschaften nanostrukturierter Systeme. Fortschritte hinsichtlich der Größen‐ und Formkontrolle magnetischer Nanopartikel wurden durch Methoden wie Mitfällung, thermische Zersetzung und/oder Reduktion, micellare Synthesestrategien und Hydrothermalsynthese erzielt. Entscheidend ist immer noch der Schutz gegen Korrosion, weshalb ein Schwerpunkt auf geeignete Schutzstrategien gelegt wird – z. B. Tensid/Polymer‐, Silicat‐ und Kohlenstoff‐Beschichtung magnetischer Nanopartikel sowie ihre Einbettung in eine Matrix oder ein Trägermaterial. Geschützte magnetische Nanopartikel können als Bausteine für verschiedene funktionale Systeme verwendet werden, und ihre Anwendung in Katalyse und Biotechnologie wird ebenfalls kurz diskutiert. Zum Schluss werden einige Trends auf diesen Forschungsgebieten umrissen und Ausblicke auf zukünftige Entwicklungen gegeben.
Rheological properties of new polymer compositions for sand consolidation and water shutoff in oil wells
Authors: Lahalih S. M. , Ghloum E. F.
Published: February 2007

The rheological properties of some newly developed polymer compositions have been investigated with and without crosslinking. These polymer compositions were developed as a water shutoff and sand consolidation treatment agents for producing oil and gas wells. The effects of several variables on the rheology of the compositions were evaluated over a wide range of temperatures (25–110°C), shear rates (0–500 s−1), brine percentages (0–15%), crosslinker types and concentrations (0–3%), and polymer concentrations (6–50%). It was found that increasing the shear rate from 0 s−1 to 100 s−1 caused shear thinning and reduction of the viscosity of the dilute solutions (6–13%) from 25 cP to ∼ 3 cP at 80°C. In contrast, for the concentrated solutions (20–50%), the viscosity dropped slightly in the shear rate range 0–10 s−1, and subsequently decreased more slowly up to shear rates of 500 s−1. The viscosities of all polymer solutions dropped by a factor of 2 as the brine concentration increased from 0% to 15%. Finally, aging time coupled with shear rates and higher percentages of crosslinkers accelerate the buildup of viscosity and gelation time of the polymer compositions. For concentrated solutions, shear rates ranging within 0–200 s−1 accelerated gelation time from 9.75 h to 2–3 h, when they were sheared at 80°C. The polymeric solutions exhibited Newtonian, shear‐thinning (pseudo‐plastic), and shear‐thickening (dilatant) behavior, depending on the concentration, shear rate, and other constituents. In most cases, the rheological behavior could be described by the power law. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Preparation mechanism and characterization of a novel, regulable hollow phenolic fiber
Authors: Zhang Dongqing , Shi Jingli , Guo Quangui , Song Yan , Liu Lang , Zhai Gengtai
Published: February 2007

A novel hollow phenolic fiber was successfully prepared by the dissolution of the uncrosslinked core of the partially crosslinking spun filament derived from the melt spinning of the phenolic resin. A series of hollow phenolic fibers with various degrees of hollowness were obtained through different preparation processes. The hollow phenolic fibers were characterized with scanning electron microscopy, infrared spectrometry, and thermogravimetric analysis. The formation of the hollow core in the hollow phenolic fibers was attributed to partial crosslinking of the filaments during the curing process; the prepared hollow phenolic fibers had high crosslinkage after the second cure, their thermal stability was as excellent as that of the solid phenolic fiber, and their hollowness could be regulated from 5 to 85%. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Conservation and management of the rivers of the Kruger National Park: Suggested methods for calculating instream flow needs
Authors: O'Keeffe Jay , Davies Bryan
Published: February 2007

1. Six major river systems flow west to east across the Kruger National Park (South Africa). All arise outside the western boundary of the KNP, and are outside the jurisdiction of the Park authorities.

2. Growing human populations to the west of the Park are placing increasing demands on the water resources of these rivers, and a variety of artificial changes threaten the ecological integrity of the rivers.

3. As a result, the Luvuvhu and Letaba Rivers to the north no longer have a perennial flow, while the flow of the Crocodile River on the southern boundary of the Park has been regulated to a more constant regime due to irrigation demands. The Letaba, Olifants, and Crocodile Rivers all receive diverse pollutants. The Sabie River, at present the least disturbed system, and biologically the most diverse in South Africa, is threatened with multiple regulation within the next five years.

4. The paper describes the development of initial protocols for the assessment of instream flow needs for the Luvuvhu and Sabie Rivers. These methods require an extension of existing methods developed in the USA to ensure the maintenance of ecological processes, rather than the maintenance of single target species.

5. Two methods are described: one that identifies the consumptive and non‐consumptive water requirements of the rivers, adding all consumptive to the limiting non‐consumptive quantity to give a base‐flow requirement.

6. A second method uses a conservation status model to assess the ecological consequences of flow reductions generated through a hydrological model, in response to different impoundment conditions.

7. Both methods are successful in appropriate circumstances, but we conclude that the proposed impoundment and agricultural development of the Sabie River, in particular, is an inappropriate use of this unique resource, and that the catchment would be more advantageously developed for tourism, recreation, and nature conservation.
The use of multivariate analytical techniques in conservation assessment of rocky seashores
Authors: Fuller I. A. , Telfer T. C. , Moore C. G. , Wilkinson M.
Published: February 2007

1. This paper describes the use of multivariate analytical techniques as an aid to classifying and assessing the nature conservation value of rocky intertidal communities round the Northern Ireland coastline.

2. Semiquantitative species abundance data from 128 rocky shore transects distributed round the coastline were subject to multivariate analysis in order to formulate a classification scheme for shore communities. Several different techniques were used on the grounds that a robust classification scheme should not be dependent upon the details of statistical methodology. Cluster analysis (three strategies) and TWINSPAN were used to produce hierarchical classification schemes, and ordination was used to assess the validity of suggested community boundaries.

3. The resulting classification scheme of rocky shore communities is presented and discussed in terms of the six scientific/ecological criteria which Mitchell (1987) identified for the comparative evaluation of marine habitats and communities for nature conservation purposes.
Invertebrate assemblages of Essex salt marshes and their conservation importance
Authors: Mason C. F. , Heath D. J. , Gibbs D. J.
Published: February 2007

1. Invertebrates were collected, using corers and sweep nets, from 25 salt marshes, and adjacent mudflats and strandlines, in Essex, eastern England, to describe assemblages and assess their conservation importance.

2. Sweep net samples were more variable in taxon richness than core samples. Neither sampling method, nor samples from the three habitats (main marsh, mudflat, strandline) could be used as an indicator of taxon richness of the salt marsh as a whole.

3. Core samples collected relatively few, but often abundant, marine species which were generally widespread and a large number of terrestrial species, which were generally restricted in distribution. The mudflat fauna was species poor. Sweep net samples of main marsh and strandline were markedly different in their species composition; many species, with generally patchy distributions, were recorded and Diptera predominated. There was no relationship between invertebrate taxon richness, plant species richness or measured environmental variables.

4. TWINSPAN was used to classify sites and invertebrate species. On the entire data set, six groups of sites were identified, but there was no trend in taxonomic richness. Only 25% of species were restricted to a single group. Sweep nets provided a much higher discrimination of sites.

5. The conservation value of salt marsh sites for invertebrates is discussed using four criteria: community distinctiveness, species richness, species rarity and community functioning. A holistic approach to the conservation of salt marshes within the region is recommended.
Reproduction, growth and diet of Gambusia holbrooki (Girard) in a temperate Australian river
Authors: Pen L. J. , Potter I. C.
Published: February 2007

1. The biology of Gambusia holbrooki in the Collie River in southwestern Australia is described using data obtained from seine samples collected at 4–6 weekly intervals over two years.

2. Females which had overwintered in the river bred between October and February (spring‐breeding group) and then died. Some of the large representatives of the resultant cohort of males and females bred between January and March (summer‐breeding group) and then also died. The offspring of these larger individuals and the smaller fish did not start breeding until the following spring, when they constituted the spring‐breeding group of the following breeding season. Breeding occurred when temperatures were above 15–16°C and day length exceeded 750–780 min. The increase in the mean length of the spring group of pregnant females from 33 mm in October to 52 mm in January was accompanied by a rise in mean fecundity from 33 to 131.

3. In the Collie River, G. holbrooki is a generalist carnivore, feeding at the water surface and throughout the water column. Gut contents of a wide size range of G. holbrooki from each season contained neither the eggs, larvae, juveniles nor adults of any of the three indigenous fish species found in the system. Moreover, there was no evidence that G. holbrooki exhibited agonistic behaviour, such as fin clipping, towards these native fish.

4. Coexistence of the three indigenous species with G. holbrooki, and thereby their conservation, is facilitated by the outcome of different spawning times and localities. Thus, the early life‐history stages of the indigenous species, which are most susceptible to predation, are typically produced in tributary creeks or flood waters between late winter and late spring, some time before the breeding of G. holbrooki results in a population explosion of this exotic species in the main channel of the river during summer.
Mitigating the impacts of stream and lake regulation in the flathead river catchment, Montana, USA: An ecosystem perspective
Authors: Stanford Jack A. , Richard Hauer F.
Published: February 2007

1. Seventy‐two per cent of the Flathead River catchment (22 241 km2) is federally designated and protected as wilderness or national park. Thus, the catchment remains one of the more pristine areas of its size in the temperate latitudes of the world.

2. Discharge in the downstream reaches of the river system outside the protected areas is regulated by three dams for flood control and hydropower production. These dams have blocked natural migration of native fish from Flathead Lake (496 km2) and isolated populations in sub‐catchments. Temperature and erratic flow fluctuations have altered phenologies of river zoobenthos and fish, and in dam tailwaters aquatic biodiversity is drastically reduced in comparison to unregulated segments.

3. Ecological problems caused by changing water quality conditions, altered land‐use patterns and introductions of non‐native biota are interactive with the impacts of stream and lake level regulation, thereby emphasizing the complexity of this river–lake ecosystem.

4. Mitigation of the effects of regulation is compromised by differing management priorities and regulatory mandates of County, State, Tribal, and Federal agencies responsible for natural resource management within the catchment. Moreover, economic and ecological interests outside the Flathead influence the way flows are regulated within the catchment.

5. The most pervasive influences of stream and lake regulation can be ameliorated by retrofitting the hypolimnial release dam with a selective depth outlet structure to allow temperature control, and by controlling changes in flow rates to create a more natural hydrograph in the tailwaters of the large dams. Allowing fish passage by construction of fish ladders is problematic because upstream passage will commingle native species that were isolated upstream by construction of the dams with non‐native species that were introduced subsequently below the dams. Cascading food web interactions elicited by invasions of non‐native biota may offset any advantage to native stocks gained by passage and/or augmentation with hatchery stocks.

6. Mitigation must be adaptive in the sense that unanticipated effects and interactions with other management objectives can be documented and alternative action can be implemented.

7. This case history of the effects of stream and lake level regulation, and the approaches to management reviewed in this paper, should serve as a lesson in river conservation.
The conservation status of the Nee Soon freshwater swamp forest of Singapore
Authors: Ng Peter K. L. , Lim Kelvin K. P.
Published: February 2007

1. The most important area in Singapore for native aquatic fauna and flora is a relatively intact 5 km2 patch of freshwater swamp forest in Nee Soon.

2. The Nee Soon Swamp Forest contains 48% of the primary freshwater fish, 71% of the amphibian, 28% of the reptile and 34% of the bird fauna of Singapore. The swamp also has the highest percentage of native and threatened freshwater fish and crustacean species on the island, as well as being the main (if not the only) habitat of the aquatic plant Hydrostemma. It is also the last refuge of two mammals, the Banded Leaf Monkey, Presbytis femoralis femoralis, and the Cream‐coloured Giant Squirrel, Ratufa affinis affinis.

3. The threats to the swamp forest are discussed, and proposals are made to establish the swamp forest as Singapore's second major nature reserve.

4. Study of the swamp forest is essentially still at a survey and discovery phase. The research priorities are to establish detailed species lists, the status of endangered species and the extent of buffer zones.

5. The swamp forest is administered primarily by the newly established National Parks Board, but several other government organizations also have jurisdiction over the land, causing some problems in the management of the swamp. The roles of the university and non‐governmental organizations in conducting surveys, drafting recommendations and educating the general public are detailed.
Sea defence and nature conservation: Threat or opportunity
Authors: Doody J. P.
Published: February 2007

1. New land has been ‘won’ from the sea by the process of embankment for centuries. It is perhaps not surprising, given the long term commitment to the protection of the land so created, that current works are concerned largely with reinforcing the existing line of sea defence.

2. Those concerned with nature conservation have likewise in the past, expended considerable energy in trying to protect natural and semi‐natural habitat from destruction and exploitation by man. This has included land claim and associated sea defence works.

3. This paper examines these two perceptions of ‘coastal protection’ and suggests a more enlightened approach which accepts change as an important part of coastal development, and provides a more positive way forward. Those concerned with sea defence and nature conservation may have to accept that protection of the current line of sea defence or existing coastal habitats, may not be the best option in all cases.
Strawberry creek on the University of California, Berkeley campus: A case history of urban stream restoration
Authors: Charbonneau Robert , Resh Vincent H.
Published: February 2007

1. Strawberry Creek (37°52′ N; 122°15′ W) is the major focus of open space on the University of California, Berkeley (Alameda County, California, USA) campus; it provides visual amenity and variety, riparian and wildlife habitat, and educational and recreational opportunities.

2. Since the beginning of this century, urbanization of the catchment, channel alteration and water quality degradation combined to cause deterioration of the creek's habitat and overall environmental quality; this was manifested by a marked absence of flora and fauna, obvious water pollution and severe erosion.

3. In 1987 a restoration project was undertaken that focused on water‐pollution and erosion‐control measures. In 1989, native three‐spined sticklebacks (Gasterosteus aculeatus) were successfully reintroduced. Family Biotic Index scores for the macroinvertebrate community indicated a change from the ‘poor’ water quality conditions in 1986 to ‘good’ water quality in 1991.

4. Environmental education programmes now involve over 1500 students who use the creek each year in laboratory exercises; a popular natural history and conservation walking‐tour guidebook has also been prepared.

5. On‐going restoration efforts include additional reintroductions of other native species, further environmental education efforts and monitoring.

6. Obstacles and key factors that led to the successful implementation of this project are presented to assist in implementing similar ecological restoration projects of urban streams.
An assessment of the ecological impacts of inter‐basin water transfers, and their threats to river basin integrity and conservation
Authors: Davies Bryan R. , Thoms Martin , Meador Michael
Published: February 2007

1. Detailed research into the ecological impacts of inter‐basin water transfers (IBTs) is virtually nonexistent on a global scale. However, a growing awareness of the serious nature of such impacts—for example, the loss of biogeographical integrity, the loss of endemic biotas, the frequent introduction of alien and often invasive aquatic and terrestrial plants and animals, the genetic intermixing of once separated populations, the implications for water quality, the frequently drastic alteration of hydrological regimes, the implications for marine and estuarine processes, climatic effects, and the spread of disease vectors, amongst many others—demands a most urgent and world‐wide appraisal of all current planning and research strategies.

2. This paper first defines the types of extant IBTs, and details some case studies for three widely separated regions of the world, namely: south‐eastern Australia, southern Africa, and the central and south‐western parts of the United States of America. In doing so, it highlights the chronic paucity of ecological data on their impacts, while simultaneously emphasising their extreme complexities.

3. Finally, we call for an international meeting on such schemes, as a matter of priority and extreme urgency, in order to assess the extent of IBTs, their geographical distribution, and their ecological and sociological impacts and implications.
Particular problems for the conservation of diadromous fish
Authors: McDowall R. M.
Published: February 2007

1. Known diadromous fish number <250 species, and <1.5% of fish species.

2. They comprise ca. 3% of species regarded as ‘endangered’.

3. Amongst them are species of great importance to fisheries, and out of proportion to their number.

4. They occupy complexes of connected habitats between or through which passage is needed at two or more life history phases.

5. They therefore pose special problems for conservation which relate to: a. diversity of habitats; b. huge areas occupied; c. the spatial separation of the various habitats used; d. need for fish passage; e. often heavy exploitation.

6. These problems are often the opposite of those experienced with species that occupy local habitats and which are in danger of local extirpation.
Progress and opportunities for advancing marine nature conservation through coastal zone management in the United Kingdom
Authors: Gubbay S.
Published: February 2007

1. The idea of ‘Coastal Zone Management’ (CZM) has received a great deal of attention in the UK in the past three years.

2. There is no formally recognized CZM programme but recent significant developments are leading towards its implementation.

3. This ‘Viewpoint’ describes the progress which is being made and discusses the potential benefits to marine nature conservation that could result from a programme of integrated CZM.
Vegetation succession in lakes in the coastal fringe of West Connemara, Ireland
Authors: Van Groenendael J. M. , Van Mansfeld M. J. M. , Roozen A. J. M. , Westhoff V.
Published: February 2007

It is hypothesized that the recent intensification of agricultural practice in the coastal fringe of West Connemara, Ireland, has affected the vegetation of vulnerable ecosystems like lakes and wetlands.

Lakes and wetlands, arranged in three transects running inland from the coast, were studied to detect an assumed decrease in the effects of eutrophication as a result of a decrease in the intensity in land use.

The data obtained from the vegetation survey in 1988 were compared with those collected at the same sites in 1975. The data were subjected to various multivariate statistics to detect changes in species composition and relationships between these changes and environmental variables such as pH and orthophosphate concentration in the surface waters.

Changes in species composition are accompanied by changes in environmental factors; notably a marked increase in orthophosphate level indicating an anthropogenic origin for most of the observed changes in vegetation.

Changes in species composition have also been used to construct a transition matrix for sites between 1975 and 1988. This has served as a basis for a prognosis on the state of the vegetation at these sites circa 2000. Data have also been grouped to indicate lake‐specific patterns in the changes.

The dynamics of all plant species have been established based on their frequency of disappearance from sites since 1975 and their rate of establishment in new sites in 1988. Special attention has been given to species from the red data list. It is concluded that over the past 13 years species diversity decreased in the whole area, and especially in coastal lakes. Red data list species appeared to be the more vulnerable ones.
Re‐establishment of Danish streams: Restoration and maintenance measures
Authors: Iversen Torben Moth , Kronvang Brian , Madsen Bent Lauge , Markmann Peter , Nielsen Mogens Bjørn
Published: February 2007

Prior to 1983 the Danish legislation concerning streams gave priority to drainage of water. The revision of The Watercourse Act gave balanced priority to drainage of water and environmental quality, focusing on an ecologically more appropriate maintenance practice and giving special provisions for stream restoration activities.

Different measures of single structure restoration have been used, the most common being replacement of weirs, dams or other obstacles by rapids, establishment of salmonid spawning grounds, and installation of new or improved fish ladders.

The most common stream channel restoration method is integrated use of a number of single structure measures. Establishment of a two‐stage channel and re‐opening of small piped streams have also been used. Stream valley restoration includes restoration of old meanders or establishment of a new sinuous channel and involves the adjacent riparian areas.

The changed stream maintenance practice involves a new strategy for dredging and cutting of weeds and bank vegetation in order to minimize the ecological damage caused by keeping a reasonable discharge capacity. In 1990, environmentally acceptable weed‐cutting was performed in 37% of all municipal streams and the bank vegetation was left uncut in a third of the streams. Similarly, more than half of the county streams were maintained using hand scythes and in 74% of the streams the bank vegetation was left uncut.

Quantitatively, stream restoration has contributed little to the general improvement of Danish streams compared with changed maintenance practice. Stream restoration projects create public interest in the environmental quality of streams, but major improvements in the physical properties of Danish streams depend on future maintenance practice.

Due to major changes predicted in Danish agriculture many riparian areas and wetlands will reappear and the natural or semi‐natural physical properties of streams will be re‐established by natural processes or changed in maintenance practice. However, there will still be large areas with intensive agriculture, where environmental and agricultural interests must be balanced. The Danish experience has shown that this is possible.
Initial habitat response to incised channel rehabilitation
Authors: Douglas Shields F. , Cooper Charles M. , Knight Scott S.
Published: February 2007

Incised stream channel aquatic habitats typically are severely degraded. After the primary knickpoints or knickzones have passed, base flows are limited to shallow channels flanked by sandy berms within the enlarged high‐flow channel. Riparian vegetation, woody debris and pool habitat are in short supply, and stream systems become disengaged from their floodplains.

We hypothesized that habitat recovery might be accelerated in channels that have incised and are regaining equilibrium through deposition of sandy berms by placing rock spurs in the channel and by planting woody vegetation on the berms. On the basis of literature review and a pilot study, planting designs were developed for a large‐scale field experiment: 2550 1.5 m long cuttings of native willow (Salix spp.) 2–25 cm in diameter were planted 1–1.2 m deep along the base‐flow channel of an incised stream. A ridge of stone was placed on the water side of the plantings, and 17 rock spurs were constructed by extending existing spur dikes from the opposite bank.

Woody cover along the treated bank increased from 38% to 66% of bankline after one growing season. Survival of individual plantings was reduced from an estimated 60% to an observed 34% by competition from the exotic kudzu vine, Pueraria lobata. Mean depth and mean scour hole depth, corrected for stage variation, increased 44% and 82%, respectively. Mean scour hole width increased 130%. The mean length of fish and the number of fish species approximately doubled, while the total weight of fish captured by a unit of sampling effort increased by an order of magnitude.
Potential effects of incidental mortalities on the Hooker's sea lion (Phocarctos hookeri) population
Authors: Woodley Thomas H. , Lavigne David M.
Published: February 2007

Annual rate of increase (r) was estimated for the Hooker's sea lion (Phocarctos hookeri) using demographic models that incorporated age‐specific estimates of reproductive rate (mx) and survival (lx).

In the absence of empirical estimates of natural mortality (nx), survival schedules were derived by combining a range of incidental mortality rates (hx) in commercial fisheries with estimates of nx for two species that exhibit similar life histories to Hooker's sea lions: northern fur seals (Callorhinus ursinus), model A, and Himalayan thar (Hemitragus jemlahicus), model B. Model A represented a population that would have a limited capacity for population increase; incidental mortality rates of mature females above about lo would result in a population decline. Model B represented a population that, even in the absence of incidental mortalities, would just remain stable.

If either of these models accurately represents the population demography of Hooker's sea lions, then these animals have limited capacity for population increase. They are constrained by relatively delayed maturity, moderate reproductive rates and short life spans.

While absolute estimates of r from our models must be interpreted with caution, it is the responses of r to incidental mortalities and to increased natural mortality of pups that are most informative. Both models show r decreasing by 0.007–0.008 with a 0.01 increase in incidental mortalities of mature females. Both models also indicate that an increase in the natural mortality of pups by 0.027 will reduce r by 0.0055 or more.

Given the paucity of available empirical data, our results suggest that incidental mortalities of Hooker's sea lions in the trawl fishery for arrow squid (Nototodarus sloanii) should be minimized if a population decline is to be avoided.
Case studies and reviews. Analysis of current policies and alternative strategies for the reduction of nutrient loads on eutrophicated lakes: The example of Slapton Ley, Devon
Authors: Wilson Helen M. , Gibson Mary T. , O'sullivan P. E.
Published: February 2007

The efficacy of strategies to reduce external nutrient loads to eutrophicated lakes may be evaluated using the example of Slapton Ley, a freshwater Site of Special Scientific Interest in south‐west England.

The results of this study suggest that, in dealing with eutrophication, a reduction in point‐source loads is important, but attention must also be given to non‐point, agricultural sources.

One measure which would appear to be effective against diffuse nutrient export from farmland involves the creation of woodland buffer zones along the courses of the rivers draining into the Ley.

Problems arise in the implementation of strategies since it is concluded that no current EC or UK national legislation addresses the problem of freshwater eutrophication in a comprehensive manner.

Forthcoming Statutory Water Quality Objectives may be instrumental in providing the legal means by which such reductions could be achieved, if the importance of diffuse sources from agriculture is acknowledged.
Viewpoint. Management of Marine Protected Areas in the UK: Lessons from statutory and voluntary approaches
Authors: Gubbay Susan
Published: February 2007

The establishment of Marine Protected Areas in the UK has been an extremely slow process. Two sites have statutory protection and a further nine are voluntary marine conservation areas.

There has been a distinctly different approach to site protection depending on whether the initiative is statutory or voluntary. The advantages and disadvantages of each are illustrated through examples.

Sites with voluntary protection are often seen as positive, and involving the local community. The overriding issue for legally protected sites is concern that they are a threat to existing rights.

A combined approach is needed. There should be statutory protection for key sites, whereas voluntary marine protected areas should be encouraged all around the coast, regardless of whether an area is of nature conservation value.

A key lesson to learn from the voluntary approach is the need to involve people who will be affected by the proposals as early as possible.
Phosphorus fractionation and mobility in Loch Leven sediments
Authors: Farmer J. G. , Bailey‐Watts A. E. , Kirika A. , Scott C.
Published: February 2007

This paper reports on the application of a chemical fractionation scheme for assessing the amounts, forms and potential mobility (recycling potential) of phosphorus in the sediments of the freshwater Loch Leven, which is currently highly topical in relation to eutrophication and its manifest dense, potentially toxic, blue‐green algae. The findings are placed in the context of the biological importance of the loch, the problems it is experiencing and some management options for its restoration.

The fractionation scheme adopted enabled quantification of phosphorus in sediment pore water and in sedimentary solid phases classified as ‘loosely‐bound’, ‘reductant‐soluble’, ‘oxide‐adsorbed’, ‘organic’, ‘apatite‐bound’ and ‘residual’ in the sections of a 16‐cm core collected in January 1990.

Vertical profiles of reductant‐soluble and pore water phosphorus and iron show redox‐controlled remobilization and cycling within the sediment to be the principal mechanisms leading to the surface sediment enrichment of phosphorus observed during the winter months.

The association of phosphorus with iron oxyhydroxides in the reductant‐soluble fraction, which accounts for 31% of the total phosphorus (2470 mg kg−1) in the 0–1 cm section compared with 0.5% loosely‐bound, 25.6% oxide‐adsorbed, 27.9% organic, 9.9% apatite‐bound and 5.1% residual, restricts the release of phosphorus to the overlying water column in winter.

Extrapolation of the data to the whole loch suggests that in early 1990 more than 40 tonnes of phosphorus were associated with the surfaces of iron oxyhydroxides in the upper 10 cm of Loch Leven sediment, about five times that required to raise loch water concentrations to maxima of 0.15 mg L−1 observed during the algal blooms of summer under conditions favourable to the release of phosphorus from the sediments.

Despite recent measures to reduce external inputs of phosphorus and thereby limit the degree of eutrophication of Loch Leven, there appears to have been little overall change in the inventory of phosphorus associated with iron in the upper 10 cm of sediment since 1970.

There should be more detailed seasonal and spatial studies of the chemical fractionation and mobility of phosphorus in Loch Leven sediments to investigate the extent to which release from the reductant‐soluble iron oxyhydroxide fraction (internal loading) contributes to the highly elevated phosphorus concentrations in loch water during summer.
Conservation of the Blythe, a high quality river in a major urban area in England
Authors: Box J. D. , Walker G. J.
Published: February 2007

The River Blythe lies between the cities of Birmingham and Coventry. It has been notified recently as a statutory Site of Special Scientific Interest (SSSI) and is one of the few whole‐river SSSIs in Britain.

It possesses a combination of natural course and structure which is a rare feature of lowland rivers in England. There is a clear succession of plant communities from its source to its confluence with the River Tame. Botanically it is one of the richest rivers in England.

A study in 1982 recorded 159 macroinvertebrate taxa from the river. A notable feature is the species richness of the molluscs, oligochaetes and caddis‐flies.

The Blythe is subject to a range of pressures including land drainage, recreation and development (buildings and infrastrucure). The appropriate option for its conservation management is limitation of catchment development.

In order that this nationally important resource is conserved for future generations, a strategic approach to catchment management is needed combined with urban and infrastructure developments which are environmentally sustainable.

The preparation of a catchment management strategy needs to be given a priority. The success of such a strategy will be dependent on cooperation between English Nature, the National Rivers Authority, the local planning authorities and the many riparian owners and occupiers.

English Nature is cooperating with the National Rivers Authority to produce a ‘special ecosystem’ classification so that statutory Water Quality Objectives can be set to protect river SSSIs like the Blythe.

8. The goodwill of the riparian owners and occupiers is needed for the protection and enhancement of wildlife habitats along the river.
Marine reserve site selection along the Abel Tasman National Park coast, New Zealand: Consideration of subtidal rocky communities
Authors: Davidson Robert J. , Chadderton W. Lindsay
Published: February 2007

At present, marine reserves do not represent the full range of community types throughout New Zealand.

To assist with the placement of a marine reserve along the Abel Tasman National Park coast (northern South Island), dominant subtidal laminarian and fucoid algae, echinoids and herbivorous molluscs were quantitatively investigated. Results from 100 quadrats collected from 19 random transects at six selected sites showed that algae and grazer assemblages varied between granite and limestone substrata.

Granite had a high percentage cover of crustose coralline algae (mean 82%–90%), a sublittoral fringe of brown macroalgae and no Ecklonia radiata or red foliose algae. Limestone sites were distinguished by a relatively low percentage cover of coralline algae (mean 13%) and high cover of foliose red algae and E. radiata (2%–36% cover and 0.2–13.9 stipes m−2, respectively).

On limestone, molluscs Turbo smaragdus and Cookia sulcata, and the echinoid Evechinus chloroticus were larger than those on granite. On limestone sites with little macroalgae, herbivore size was intermediate. Grazers were more abundant on granite than limestone (mean 34.6 m−2, and 10.8 m−2 respectively).

Differences in herbivore composition were recorded between granite substrata, while both algal and herbivore composition varied between limestone sites.

We suggest that a variety of environmental factors including substratum influence algal and herbivore assemblages along the Abel Tasman coast.

It is recommended that selection of a marine reserve site or sites along the coast of Abel Tasman National Park recognizes differences in community structure both between and within limestone and granite substrata.