EFFECTS OF METHOD OF ESTABLISHMENT ON TALL FESCUE AND ITALIAN RYEGRASS MIXTURES IN THE FOLLOWING YEAR

Tall fescue and Italian ryegrass mixtures react differently to management in the year of sowing. The decrease in yield of tall fescue and the increase in growth of red clover, caused by the use of a cover crop, was still evident in the following year. In both the spring grazing and total yield of the first harvest year, the Italian ryegrass/ white clover mixture was better than the tall fescue/white clover mixture when a cover crop was used. The reverse trend was recorded when the grass plus clover was sown without the cereal. In general, the addition of red clover to the tall fescue/ white clover, or Italian ryegrass/white clover mixture, increased the yield, but the magnitude of the increase was modified by management during establishment. The increase in total herbage yield and the reduction of white clover growth due to nitrogen application were both related to management in the year of sowing. Consideration should thus be given to method of establishment in the assessment of herbage seeds mixtures.     

Micromorphology of soils in soliflucted materials,Okstindan, Northern Norway

The micromorphology of two soil profiles developed on turf-banked solifluction lobes and a third profile formed on a larger turf-banked solifluction terrace is described. Four elements common to the three profiles are identified.In the horizontal plane the apparent long axes of detrital grains show preferred orientation parallel to the azimuth of the line of greatest slope, and in slides cut in the vertical plane aligned with the slope direction a somewhat stronger preferred orientation (or apparent dip of the grains) is observed parallel, or sub-parallel to the ground surface gradient. Secondly, coatings of matrix material are observed on the upper surfaces of detrital grains at depths greater than 50 cm. Above this depth similar coatings also appear on the sides and lower surfaces of detrital grains. Roughly horizontal flattened patches of matrix enrichment are also observed in the three profiles. These become more frequent with depth, producing a banded pattern of matrix concentrations separated by detrital grains. Finally, large rounded pores, or vesicles, are observed in the upper 25 cm of the three profiles.These micromorphological elements are described, and suggestions are made as to their origins.     

Conservation and the low population density of invertebrates inside neotropical rain forest

Counts of invertebrates by sweep-netting and beating the stratum of rain forest vegetation between 6 in (15 cm) and 6 ft (1·8 m) have been made during rainy season conditions in N. Brasil and on Barro Colorado Island, Panama Canal, the latter from measured volumes of habitat. This work has been repeated on BCI during the dry season. The average population densities of total catches were 0·97 m³ for rainy season and 1·09 m³ for dry season. Species diversity was very high, therefore numbers per species extremely low. It is suggested that such low population density brings hazards of local extinction, and that the maintenance of such a system depends on the existence of extensive habitat from which recolonisation can occur. If this is so, reserves in rain forest will have to be very large, to ensure long-term survival of many of the invertebrate species.     

Therapeutic Potential and Nutraceutical Profiling of North Bornean Seaweeds: A Review

Malaysia has a long coastline surrounded by various islands, including North Borneo, that provide a suitable environment for the growth of diverse species of seaweeds. Some of the important North Bornean seaweed species are Kappaphycus alvarezii, Eucheuma denticulatum, Halymenia durvillaei (Rhodophyta), Caulerpa lentillifera, Caulerpa racemosa (Chlorophyta), Dictyota dichotoma and Sargassum polycystum (Ochrophyta). This review aims to highlight the therapeutic potential of North Bornean seaweeds and their nutraceutical profiling. North Bornean seaweeds have demonstrated anti-inflammatory, antioxidant, antimicrobial, anticancer, cardiovascular protective, neuroprotective, renal protective and hepatic protective potentials. The protective roles of the seaweeds might be due to the presence of a wide variety of nutraceuticals, including phthalic anhydride, 3,4-ethylenedioxythiophene, 2-pentylthiophene, furoic acid (K. alvarezii), eicosapentaenoic acid, palmitoleic acid, fucoxanthin, β-carotene (E. denticulatum), eucalyptol, oleic acid, dodecanal, pentadecane (H. durvillaei), canthaxanthin, oleic acid, pentadecanoic acid, eicosane (C. lentillifera), pseudoephedrine, palmitic acid, monocaprin (C. racemosa), dictyohydroperoxide, squalene, fucosterol, saringosterol (D. dichotoma), and lutein, neophytadiene, cholest-4-en-3-one and cis-vaccenic acid (S. polycystum). Extensive studies on the seaweed isolates are highly recommended to understand their bioactivity and mechanisms of action, while highlighting their commercialization potential.     

Effects of Co‐stocking Smallmouth Buffalo,Ictiobus bubalus,with Channel Catfish,Ictalurus punctatus

Proliferative gill disease (PGD) in catfish is caused by the myxozoan Henneguya ictaluri. The complex life cycle requires Dero digitata as the oligochaete host. Efforts to control PGD by eradicating D. digitata have been unsuccessful. Smallmouth buffalo, Ictiobus bubalus, (SMB) are opportunistic bottom feeders and a putative option for controlling D. digitata. In 2011, 15 ponds (0.4 ha) were stocked with 5000 channel catfish, Ictalurus punctatus; 7 of these 15 ponds were also stocked with 300 SMB fingerlings. There were no differences in benthic invertebrate numbers or water quality variables between ponds with or without SMB. At harvest, there were no differences in percent survival, total weight, or catfish feed conversion ratio. In the second year, 18 ponds (0.4 ha) were stocked with 6000 channel catfish. Half the ponds were also stocked with 300 SMB. Sentinel fish were used to estimate disease severity, and pond water was collected for molecular estimation of H. ictaluri actinospore concentrations. Similar to the first year, there were no differences between treatments in any variable tested, including PGD severity in sentinel fish and parasite concentrations in pond water. Under these study conditions, presence of SMB did not have a measureable effect on PGD incidence, parasite density, or overall catfish production.     

From shallow to deep waters: habitats used by larval lampreys (genus Petromyzon and Lampetra) over a western European basin

Abstract –  Habitat requirements of lamprey ammocoetes (Petromyzon marinus and Lampetra genus) were investigated, for the first time, from shallow to deep waters, at different spatial scales across the Gironde‐Dordogne continuum, thanks to a water suction dredge. Fish‐habitat relationships were assessed through two complementary statistical analyses: habitat‐use curves and habitat suitability models using the Boosted Regression Trees (BRT) technique. Analyses were performed on a small‐size data set that was characterised by the low prevalence of lamprey. The sea lamprey larvae occurred in deeper areas than their Lampetra genus counterparts. ‘Pools’ of 2 m’ depth and more were optimal habitats for the former species. Among the environmental variables retained to model lamprey occurrences, the mesohabitat (a categorical variable) was demonstrated to be highly influential, in terms of fine grain‐size substratum and vegetation cover. These preliminary results suggest that monitoring using the water suction dredge method may contribute to sea lamprey conservation.