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The supply of macroalgal feed materials for abalone aquaculture is threatened by increasing costs, limited availability. and the allocation of seaweed resources for other purposes. The use of biofouling Sargassum horneri (SH) as additional macroalgal biomass for abalone has been studied, albeit full inclusion is discouraged due to low utilization. This study applied heat treatment and fermentation to increase the nutritive value of SH meals for the aquaculture feed industry. Untreated (UN) as control, heat treated (HT, 121[degrees]C for 20 min), and fermented (FE, 10' CFU/mL each of Bacillus sp. SJ-10 and Bacillus sp. KRF-7) SH meal was fed to the abalone (11.60 [+ or -] 0.02 g body weight and 42.98 [+ or -] 0.53 mm shell length) for 8-wk growth trial. The results showed that there is no apparent difference in the growth performance (body weight and shell length morphometries) and survival of abalone given experimental diets (P > 0.05). The crude protein, lipid, and ash composition of edible abalone flesh were similarly unaffected (P > 0.05). The gut microbiota profile of abalone was analyzed through next-generation sequencing. The [alpha]-diversity indicators (microbial richness and abundance) were statistically similar (P > 0.05). and the [beta]-diversity of operational laxonomic units revealed short distances within samples and clustering among diet groups. The core phyla (Fusobacteria, Proteobaeteria. Tenericutes) and genera (Psychrilyohacter, Vibrio, Mycoplasma) known to inhabit the gut of abalone predominantly were likewise identilied irrespective of diets; however, there is a difference in their relative abundance. Genus Psychrilyohacter was relatively abundant in UN and FE compared with HT, whereas Vibrio and Mycoplasma had higher abundance in FE and HT-fed abalone, respectively. Taste sensory attributes were discriminated in the abalone meat using an electronic tongue. Principal component analysis of sensor scores revealed several overlapping points, resulting in a negative discrimination index (-184). which means no apparent difference in the general taste profile was detected. Furthermore, the taste screening matrix through radar mapping revealed slight intensity differences in the umami. saltiness, and sourness flavor. Overall, the methods used for heat treatment and fermentation procedures herein were ineffective in improving the nutritive value of seaweed meal for abalone. KEY WORDS: abalone, gulfweed. heat treatment, fermentation. Haliotis discus harmed, Sargassum horneri, INTRODUCTION The abalone (Haliotis spp.) is an ecologically and economically important marine gastropod mollusc worldwide. They are found in tropical and temperate regions, particularly in the low intertidaj zone of [...]

We report one year (2013-2014) of biomonitoring an insect community in a tropical old-growth rain forest, during construction of an industrial-level geothermal electricity project. This is the first-year reaction by the species-rich insect biodiversity; six subsequent years are being analyzed now. The site is on the margin of a UNESCO Natural World Heritage Site, Área de Conservación Guanacaste (ACG), in northwestern Costa Rica. This biomonitoring is part of Costa Rica's ongoing efforts to sustainably retain its wild biodiversity through biodevelopmental integration with its societies. Essential tools are geothermal engineering needs, entomological knowledge, insect species-rich forest, government-NGO integration, common sense, DNA barcoding for species-level identification, and Malaise traps. This research is tailored for integration with its society at the product level. We combine an academic view with on-site engineering decisions. This biomonitoring requires alpha-level DNA barcoding combined with centuries of morphology-based entomological taxonomy and ecology. Not all desired insect community analyses are performed; they are for data from subsequent years combined with this year. We provide enough analysis to be used by both guilds now. This biomonitoring has shown, for the first year, that the geothermal project impacts only the biodiversity within a zone less than 50 m from the project margin. Key words: DNA barcode, geothermal project, Costa Rica, biomonitoring with insects, ICE/ACG/SINAC/MINAE/GDFCF. Les auteurs rapportent les résultats d'une première année (2013-2014) de biosurveillance d'une communauté d'insectes dans une forêt tropicale ancienne, au cours de la construction d'un complexe industriel de génération d'électricité géothermique. Il s'agit de la première année de réaction de cette communauté d'insectes riche en espèces; six années subséquentes sont en cours d'analyse. Le site est situé à la marge d'un site du Patrimoine mondial de l'UNESCO, l'Área de Conservación Guanacaste (ACG), dans le nord-ouest du Costa Rica. Ce travail de biosurveillance s'inscrit dans les efforts en cours au Costa Rica pour maintenir de manière durable sa biodiversité sauvage via une intégration bio-développementale avec ses sociétés. Les outils essentiels en sont les besoins en génie géothermique, les connaissances en entomologie, une forêt riche en espèces, une intégration gouvernement-ONG, le sens commun, le codage à barres de l'ADN pour l'identification au niveau de l'espèce et les pièges Malaise. Cette recherche est faite sur mesure pour favoriser l'intégration avec la société au niveau du produit. Les auteurs combinent une vision académique avec la prise de décisions d'ingénierie sur le site. La biosurveillance nécessite un codage à barres de niveau alpha combiné avec une taxonomie et une écologie séculaires fondées sur la morphologie. Ce ne sont pas toutes les analyses de communautés d'insectes qui sont réalisées; elles le seront pour les données des années subséquentes lorsque celles-ci auront été combinées aux données de cette année. Les auteurs réalisent suffisamment d'analyses pour être utiles aux deux guildes pour l'instant. Cette biosurveillance a montré, pour la première année, que le projet de géothermie touche uniquement la biodiversité située dans une zone à moins de 50 m de la marge du projet. [Traduit par la Rédaction] Mots-clés: codes-barres à l'ADN, projet de géothermie, Costa Rica, biosurveillance d'insectes, ICE/ACG/SINAC/MINAE/GDFCF., Introduction Philosophical The detailed reactions of the biodiversity of whole terrestrial communities of tropical wild eukaryotic biodiversity, to industrial-scale perturbations, have not yet become a major topic of research interest [...]

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01620.x Byline: Sarah McCarthy-Neumann (*), Richard K. Kobe Keywords: community structure; density dependence; distance dependence; Janzen-Connell; light availability; plant-soil feedback; species coexistence Abstract: Summary 1. The Janzen-Connell (J-C) Model proposes that host-specific enemies could maintain high tree species diversity by reducing seedling performance near conspecific adults. An implicit, but untested assumption of the J-C Model is that negative conspecific feedbacks would promote replacement by heterospecific seedlings. 2. In a glasshouse experiment, we tested plant-soil feedbacks as a J-C mechanism in four temperate tree species. We assessed effects of conspecific- relative to heterospecific-cultured soil extracts on seedling survival, total mass and performance for each focal species. To test the implicit assumption of replacement by heterospecific seedlings, we also compared relative performance of conspecific versus heterospecific seedlings grown with soil extract cultured by a particular tree species. We also tested whether soil microbes caused these plant-soil feedbacks and whether low irradiance increased seedling vulnerability to pathogens. 3. When grown with conspecific versus heterospecific soil extract, Acer rubrum mass decreased, Quercus rubra mass increased and Fraxinus americana increased survival. Conspecific extract reduced Acer saccharum mass in low light but increased it in high light. To integrate survival and growth, we examined seedling performance [(mean total mass x mean survival time)/(days of experiment)] at low and high light. In conspecific versus heterospecific soil extract, seedling performance was lower in two, higher in four and neutral in 18 of 24 cases, suggesting no advantage to dispersing away from conspecifics. Based on relative seedling performance within a soil extract, conspecific seedlings were disadvantaged in two, favoured in three and neutral in 19 of 24 cases relative to heterospecific seedlings. 4. Species pairwise interactions of soil modification and seedling performance were chemically mediated, occurring regardless of sterilization. Microbes lacked host specificity and reduced performance regardless of extract source. Additionally, microbial factors reduced seedling performance for Q. rubra regardless of light availability, and for A. rubrum and F. americana only in high light. 5. Synthesis. These chemical-mediated plant-soil feedbacks probably influence community dynamics, but are inconsistent with the J-C Model. Even when a species' seedlings responded more negatively to conspecific than heterospecific soil, heterospecific seedlings were not necessarily favoured in that species' soil, precluding heterospecific replacement as an explanation for coexistence. Article History: Received 02 July 2009; accepted 17 November 2009 Handling Editor: Jeremy Burdon Article note: (*) Correspondence author. School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109, USA. E-mail: sneumann@umich.edu

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2009.01619.x Byline: Sarah McCarthy-Neumann (*[dagger]), Richard K. Kobe Keywords: community structure; density-dependence; distance-dependence; Janzen-Connell; light availability; plant-soil feedback; soil microbes; species coexistence; tropical forests Abstract: Summary 1. The Janzen-Connell (J-C) Model proposes that host-specific enemies maintain high tree species diversity by reducing seedling performance near conspecific adults and promoting replacement by heterospecific seedlings. Support for this model often comes from decreased performance for a species at near versus far distances from conspecific adults. However, the relative success of conspecific versus heterospecific seedlings recruiting under a given tree species is a critical, but untested, component of the J-C Model. 2. In a shade-house experiment, we tested plant-soil feedbacks as a J-C mechanism in six tropical tree species. We assessed effects of conspecific versus heterospecific cultured soil extracts on seedling performance for each species, and we compared performance of conspecific versus heterospecific seedlings grown with soil extract cultured by a particular tree species. Additionally, we tested whether soil microbes were creating these plant-soil feedbacks and whether low light increased species vulnerability to pathogens. 3. Among 30 potential comparisons of survival and mass for seedlings grown in conspecific versus heterospecific soil extracts, survival decreased in seven and increased in two, whereas mass decreased in 13 and increased in 1. To integrate survival and growth, we also examined seedling performance [(mean total mass x mean survival time)/(days of experiment)], which was lower in 16 and higher in 2 of 30 comparisons between seedlings grown with soil extract cultured by conspecific versus heterospecific individuals. Based on performance within a soil extract, conspecific seedlings were disadvantaged in 15 and favoured in 7 of 30 cases relative to heterospecific seedlings. 4. Species pairwise interactions of soil modification and seedling performance occurred regardless of sterilization, suggesting chemical mediation. Microbes lacked host-specificity and reduced performance regardless of extract source and irradiance. 5. Synthesis. These results, along with parallel research in temperate forests, suggest that plant-soil feedbacks are an important component of seedling dynamics in both ecosystems. However, negative conspecific feedbacks were more prevalent in tropical than temperate species. Thus, negative plant-soil feedbacks appear to facilitate species coexistence via negative distance-dependent processes in tropical but not temperate forests, but the feedbacks were mediated through chemical effects rather than through natural enemies as expected under the J-C Model. Article History: Received 01 July 2009; accepted 17 Novemer 2009 Handling Editor: Jeremy Burdon Article note: (*) Correspondence author. E-mail: sneumann@umich.edu