scholarly journals Kingdom of seashells: Explotation and culture of major commercial species

2021 ◽  
pp. 001-004
Author(s):  
Padhi Nandini
Keyword(s):  
Commercial Species

scholarly journals Preliminary evaluation for quality of dimension lumber in four common softwoods in Mongolia

2020 ◽  
Vol 66 (1) ◽  
Author(s):  
Murzabyek Sarkhad ◽  
Futoshi Ishiguri ◽  
Ikumi Nezu ◽  
Bayasaa Tumenjargal ◽  
Yusuke Takahashi ◽  
...  
Keyword(s):  
Pinus Sylvestris ◽  
Modulus Of Rupture ◽  
Preliminary Evaluation ◽  
Pinus Sibirica ◽  
Bending Properties ◽  
Picea Obovata ◽  
Dimension Lumber ◽  
Commercial Species ◽  
Characteristic Values

Abstract The quality of dimension lumber (2 by 4 lumber) was preliminarily investigated in four common Mongolian softwoods: Pinus sylvestris L., Pinus sibirica Du Tour, Picea obovata Ledeb., and Larix sibirica Ledeb. to produce high quality dimension lumber for structural use. In total 61, 39, 67, and 37 pieces of lumber were prepared for Pinus sylvestris, Pinus sibirica, Picea obovata, and L. sibirica, respectively. The lumber was visually graded and then tested in static bending to obtain the 5% lower tolerance limits at 75% confidence level (f0.05) of the modulus of elasticity (MOE) and the modulus of rupture (MOR). In addition, the effects of sawing patterns on bending properties were also analyzed. The f0.05 of the MOE and MOR were 4.75 GPa and 15.6 MPa, 3.39 GPa and 11.0 MPa, 3.78 GPa and 11.7 MPa, and 6.07 GPa and 22.3 MPa for Pinus sylvestris, Pinus sibirica, Picea obovata, and L. sibirica, respectively. These results suggested that with a few exceptions, characteristic values of MOR in the four common Mongolian softwoods resembled those in similar commercial species already used. In visual grading, over 80% of total lumber was assigned to select structural and No. 1 grades in Pinus sylvestris and Pinus sibirica, whereas approximately 40% of total lumber in L. sibirica was No. 3 and out of grades. Sawing patterns affected bending properties in Pinus sylvestris and L. sibirica, but did not affect Pinus sibirica and Picea obovata. Dynamic Young's modulus was significantly correlated with bending properties of dimension lumber for the four species. Based on the results, it was concluded that dimension lumber for structural use can be produced from the four common Mongolian softwoods.

Main drivers of spatial change in the biomass of commercial species between summer and winter in the NW Mediterranean Sea

2020 ◽  
pp. 105227
Author(s):  
Elena Lloret-Lloret ◽  
Maria Grazia Pennino ◽  
Daniel Vilas ◽  
José María Bellido ◽  
Joan Navarro ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Spatial Change ◽  
Commercial Species ◽  
Nw Mediterranean ◽  
Nw Mediterranean Sea

scholarly journals Flexibility of joint production in mixed fisheries and implications for management

2021 ◽  
Author(s):  
Florence Briton ◽  
Olivier Thébaud ◽  
Claire Macher ◽  
Caleb Gardner ◽  
Lorne Richard Little
Keyword(s):  
Economic Performance ◽  
Economic Incentives ◽  
Joint Production ◽  
Total Allowable Catch ◽  
Individual Transferable Quotas ◽  
The Past ◽  
Different Types ◽  
Commercial Species ◽  
Management Recommendations ◽  
Production Problems

Abstract Over the past decade, efforts have been made to factor technical interactions into management recommendations for mixed fisheries. Yet, the dynamics underlying joint production in mixed fisheries are generally poorly captured in operational mixed fisheries models supporting total allowable catch advice. Using an integrated ecological–economic simulation model, we explore the extent to which fishers are likely to alter the species composition of their landings in a mixed fishery managed with individual transferable quotas, the Australian Southern and Eastern Scalefish and Shark Fishery. Our simulations capture three different types of joint production problems, highlighting the flexibility that exists in terms of achievable catch compositions when quota markets provide the economic incentives to adapt fishing practices to quota availability. These results highlight the importance of capturing the drivers of fishing choices when advising TAC decisions in mixed fisheries. We also identify a hierarchy of species in this fishery, with harvest targets set for primary commercial species determining most of its socio-economic performance.

Forestry control in the Brazilian Amazon II: charcoal anatomy of 21 species

IAWA Journal ◽  
2021 ◽  
pp. 1-23
Author(s):  
Marcelo Mendes Braga Júnior ◽  
Fernanda Ilkiu Borges de Souza ◽  
Luiz Eduardo de Lima Melo
Keyword(s):  
Brazilian Amazon ◽  
Charcoal Production ◽  
Diagnostic Features ◽  
Sem Images ◽  
Axial Parenchyma ◽  
Market Control ◽  
Commercial Species ◽  
Identification Of Species ◽  
Human Practices ◽  
Perforation Plates

Abstract The production of illegal charcoal, associated with other local human practices, is responsible for the degradation of native forests, especially in the Brazilian Amazon. The need for market control and charcoal production is accompanied by the lack of comparative charcoal materials from the Amazon. Here, we describe charcoal samples of 21 Brazilian species and provide SEM images that can facilitate the charcoal identification. It is possible to distinguish the species on the basis of anatomy. Features such as vessel groupings, vessel–ray pitting, perforation plates, axial parenchyma, ray cellular composition, storied structure and secretory elements were chosen as primary diagnostic features for the identification of species. We highlight vessel groupings, axial parenchyma type and in some cases even perforation plates, which were easily observed in low magnification SEM images and can assist in the supervision by government agents. From our descriptions, evaluations and photomicrographs, it will be possible to compare charcoal from commercial species from the Amazon.

Relationships among blueberry species within the section Cyanococcus of the Vaccinium genus based on EST-PCR markers

2021 ◽  
Author(s):  
Lisa Jeannine Rowland ◽  
Elizabeth L. Ogden ◽  
James R. Ballington
Keyword(s):  
Polymerase Chain Reaction ◽  
Expressed Sequence Tag ◽  
Clustering Methods ◽  
Polyploid Species ◽  
Pcr Markers ◽  
Chain Reaction ◽  
Ploidy Levels ◽  
Commercial Species ◽  
Polymerase Chain ◽  
Expressed Sequence

Commercial blueberry species of North America belong to the Vaccinium genus, section Cyanococcus. Phylogenetic relationships of 50 accessions of different ploidy levels within Cyanococcus were investigated using 249 expressed sequence tag-polymerase chain reaction markers and standard clustering methods. Of the commercial species, tetraploid V. corymbosum grouped most closely with the diploids, V. fuscatum and V. caesariense, followed by the diploid V. elliottii. Tetraploid V. angustifolium grouped with the diploids, V. boreale and V. myrtilloides. Hexaploid V. virgatum grouped most closely with the diploid V. tenellum, thus shedding light on the origins of these polyploid species.

scholarly journals Unravelling the impact of harvesting pressure on canopy-forming macroalgae

2016 ◽  
Vol 67 (1) ◽  
pp. 153 ◽  
Author(s):  
Doriane Stagnol ◽  
Renaud Michel ◽  
Dominique Davoult
Keyword(s):  
Habitat Characteristics ◽  
Spatiotemporal Variability ◽  
Macrobenthic Assemblages ◽  
Wide Range ◽  
The Matrix ◽  
Commercial Species ◽  
Canopy Removal ◽  
The Impact ◽  
Relevant Finding

Canopy-forming macroalgae create a specific surrounding habitat (the matrix) with their own ecological properties. Previous studies have shown a wide range of responses to canopy removal. Magnitude and strength of the effects of harvesting are thought to be context-dependent, with the macroalgal matrix that can either soften or exacerbate the impact of harvesting. We experimentally examined in situ the effect of harvesting on targeted commercial species, and how these potential impacts might vary in relation to its associated matrix. We found that patterns of recovery following the harvesting disturbance were variable and matrix specific, suggesting that local factors and surrounding habitat characteristics mediated the influence of harvesting. The greatest and longest effects of harvesting were observed for the targeted species that created a dominant and monospecific canopy on their site prior to the disturbance. Another relevant finding was the important natural spatiotemporal variability of macrobenthic assemblages associated with canopy-forming species, which raises concern about the ability to discriminate the natural variability from the disturbance impact. Finally, our results support the need to implement ecosystem-based management, assessing both the habitat conditions and ecological roles of targeted commercial species, in order to insure the sustainability of the resource.

scholarly journals Conservation-Status Gaps for Marine Top-Fished Commercial Species

Fishes ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 2
Author(s):  
Imanol Miqueleiz ◽  
Rafael Miranda ◽  
Arturo Hugo Ariño ◽  
Elena Ojea
Keyword(s):  
Fish Species ◽  
Conservation Status ◽  
Species Conservation ◽  
Biodiversity Loss ◽  
Vulnerability Index ◽  
Iucn Red List ◽  
Red List ◽  
Commercial Fish ◽  
Commercial Species ◽  
Marine Realm

Biodiversity loss is a global problem, accelerated by human-induced pressures. In the marine realm, one of the major threats to species conservation, together with climate change, is overfishing. In this context, having information on the conservation status of target commercial marine fish species becomes crucial for assuring safe standards. We put together fisheries statistics from the FAO, the IUCN Red List, FishBase, and RAM Legacy databases to understand to what extent top commercial species’ conservation status has been assessed. Levels of assessment for top-fished species were higher than those for general commercial or highly commercial species, but almost half of the species have outdated assessments. We found no relation between IUCN Red List traits and FishBase Vulnerability Index, depreciating the latter value as a guidance for extinction threat. The RAM database suggests good management of more-threatened species in recent decades, but more data are required to assess whether the trend has reverted in recent years. Outdated IUCN Red List assessments can benefit from reputed stock assessments for new reassessments. The future of IUCN Red List evaluations for commercial fish species relies on integrating new parameters from fisheries sources and improved collaboration with fisheries stakeholders and managers.

scholarly journals Length and Weight Relationships for 31 Species of Fishes Caught by Trawl Off the Arabian Sea Coast of Oman

2008 ◽  
Vol 13 ◽  
pp. 43
Author(s):  
Brett A. Human ◽  
Haithem Al-Busaidi
Keyword(s):  
Fish Species ◽  
Arabian Sea ◽  
Stock Assessment ◽  
Fork Length ◽  
Biological Parameters ◽  
Conversion Factors ◽  
Weight Measurement ◽  
Total Length ◽  
Commercial Species ◽  
Sea Coast

Length and weight measurement for 31f ish species encountered in the Arabian Sea , o f f t h e Oma n Coast, were collected by demersal trawling during March 2007 and March 2008. A total of 3,261 specimens were measured for total length, or fork length, where appropriate, and green weight. Several commonly caught commercial species undergo onboard processing (dressing) prior to packaging, and dressed weight to green weight regressions and conversion factors were calculated for 12 of these species. The relationships obtained in this study were compared with those of other  studies for the same fish species. These data are fundamental to understanding the biological parameters of fishes, and can be applied to fisheries stock assessment and management models. 

Sign in / Sign up

Export Citation Format

Share Document