72 research outputs found

    Insight into aquaculture's potential of marine annelid worms and ecological concerns: a review

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    Polychaetes are marine annelid worms that can contribute to aquaculture diversification. Its culture has been viable, and commercially attempted, but intensive production has progressed only in few countries around the world. In the countries with no production, marine polychaetes are imported or harvested. A strong and sustained research investment provided to a better understanding of the nutritional requirements and reproduction of some species. Recent studies showed new technical improvements, which can lead to an important progress in productivity and give a new impetus to the polychaete production. Some marine worm species were identified as good candidates for integrated multitrophic aquaculture. The development of cost-effective aquaculture techniques for marine annelid worms is essential to ensure a balance between commercial interests and the preservation of ecosystems. The influence of polychaete aquaculture on the environment and vice versa raise important concerns related to ecological security and sustainability of this activity. This review focus on the main technical improvements and advances that have been made in areas as diverse as: aquaculture potential of polychaetes, reared species, main species used worldwide, and highlights biological and ecological concerns, important challenges and recommendations.This study was supported by the FCT (Portuguese National Board of Scientific Research), through the MARE (Marine and Environmental Sciences Centre) (UID/MAR/04292/2013) strategic programme and through strategic project PEst-OE/MAR/UI0199/2014, granted to MARE. This study has also the financial support of PROMAR Program through the project 31-03-05-FEP42: LIVE BAIT – Annelid polychaetes as live bait in Portugal: harvesting, import and rearing management.info:eu-repo/semantics/publishedVersio

    The Islamic Law in the Historical Study

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    Dalam kajian tentang sejarah awal Islam dan agama di dunia Barat, Islam dipandang sebagai agama \u27\u27dalam sejarab". Melaiui pandangan ini, para sarjana mempelajari sejarah awal Islam, di antaranya, dengan menggunakan meiode analisa kritik terbadap sumber-sumber sejarah termasuk kepusiakaan selain Islam dijadikan sebagai sumber dan bukti sejarah. Sejak itu pula hukum Islam dikaji melaiui pendekatan yang sama. Melaiui pendekatan ini diyakini bahwa hukum Islam mengandung tradisi-tradisi keagamaan khususnya di wilayab limur dekat yang ada sebeium Islam, dan dipandang sebagai suatu perkembangan yang berkelanjutan. Sebagaimana hasii kajian daripada Patricia Crone dan Gordon D. Newby menunjukkan bahwa di antara tradisi-tradisi keagamaan dimaksud, saiah satunya, adalab hukum Yahudi. Crone memberikan contoh qasama khususnya yang ada pada mazhab Maiiki dan mengktaim bahwa qasama dimaksud merupakan salah satu tradisi hukum yang ada pada orang-orang Yahudi. Sedangkan Newby memberikan contoh tentang penentuan orang band sebagai laki-iaki atau sebagai perempuan dalam hubungannya dengan pembagian kewarisan yang ada pada catatan \u27Amirb. Zarib di daiam sirah Ibnu Ishaq, dan mengktaim juga bahwa catatan tersebut berasai dari hukum Yahudi. Sebaliknya, pendekatan ini merupakan salah satu pendekatan yang ada dalam kajian hukum Islam dan sangat baik dipakai untuk mencari keseimhangan dan menunjukkan bahwa walaupun terdapat kesamaan antara hukum Islam dengan hukum-hukum yang lain, proses sejarab perkembangan hukum Islam itu sendiri sangat berbeda dan mempunyai karakteryang khusu

    Earthworms Use Odor Cues to Locate and Feed on Microorganisms in Soil

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    Earthworms are key components of temperate soil ecosystems but key aspects of their ecology remain unexamined. Here we elucidate the role of olfactory cues in earthworm attraction to food sources and document specific chemical cues that attract Eisenia fetida to the soil fungi Geotrichum candidum. Fungi and other microorganisms are major sources of volatile emissions in soil ecosystems as well as primary food sources for earthworms, suggesting the likelihood that earthworms might profitably use olfactory cues to guide foraging behavior. Moreover, previous studies have documented earthworm movement toward microbial food sources. But, the specific olfactory cues responsible for earthworm attraction have not previously been identified. Using olfactometer assays combined with chemical analyses (GC-MS), we documented the attraction of E. fetida individuals to filtrate derived from G. candidum colonies and to two individual compounds tested in isolation: ethyl pentanoate and ethyl hexanoate. Attraction at a distance was observed when barriers prevented the worms from reaching the target stimuli, confirming the role of volatile cues. These findings enhance our understanding of the mechanisms underlying key trophic interactions in soil ecosystems and have potential implications for the extraction and collection of earthworms in vermiculture and other applied activities

    Polychaete aquaculture and polychaete science: A mutual synergism

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