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[en] The fishing industry of the China is the largest in world which is usually believed to be facing overexploitation risk. In this condition, it becomes necessary to estimate stock status of fishery resources particularly having commercial importance. Thus, this study is the first time attempt to know whether Spanish mackerel, a major landed fishery resource in Shandong, China, is experiencing overexploitation or not by estimating its stock status. For this purpose, long data series, 2006-2016, comprised of catch and effort figures was statistically analyzed to know maximum sustainable yield (MSY) of this resource and its ongoing regime. In total, three surplus production models (SPMs) were used in this study, viz., Fox (FM), Schaefer (SM) and Pella-Tomlinson (PTM) with the help of two famous fishery statistical routines, viz., catch and effort data analysis (CEDA) and a stock production model incorporating covariates (ASPIC). For initial proportion (IP) 1, CEDA estimated MSY in a range between 41000-50000 t, whereas, ASPIC calculations remained between 44000-52000 t. Furthermore, results also showed that fishing mortality (F) is increasing while biomass (B) is swiftly decreasing. Based on the results it can be concluded that Spanish mackerel is facing the risk of overexploitation. Thus, it is recommended to make such policies which can conserve this fishery resource for future. (author)
[en] The cyanobacterium, Leptolyngbya sp. and green microalga, Chlorella sorokiniana as biofertilizers, play an important role in agriculture development. Due to a lack of information concerning microalgae as biofertilizers in crop production, the present research aimed to evaluate the possibility of increasing growth using microalgae as biofertilizers on seed germination of four commercially important vegetables i.e., radish (Raphanus sativus) subsp. sativus, spinach (Spinacia oleracea), turnip (Brassica rapa) subsp. rapa and fenugreek (Trigonella foenum-graecum). In the current study the fresh biomass of cyanobacterium, Leptolyngbya sp. and green microalga, C. sorokiniana was used as bio-fertilizers to note the effect on seed germination of four vegetables. The In vitro effects of bio-fetilizers were also noted on the different growth parameters i.e., germination percentage, days to germination (50%), plumule length, radical length, fresh weight and dry weight using Randomize Complete Designed (RCD) with factorial arrangement. The results compared with control showed an improved germination percentage using Leptolyngbya sp. (83.17%) and C. sorokiniana (80.47%). Both strains exhibited early germination (4.50 days) while C. sorokiniana showed the maximum plumule (33.88cm), radical length (4.46cm), fresh (1.38g) and dry weight (0.0708g) associated with Leptolyngbya sp. The treatment with B. rapa seed germination was 98.67% and took 1.78 days to germinate. The lowest germination (34.44%) was recorded in S. oleracea and took 6.56 days to germinate. After applying Leptolyngbya sp. on B. rapa and T. foenum-graecum seeds indicated the highest seed germination (99.67%). While B. rapa seeds germinated after one day while primed with C. sorokiniana. The maximum increase over check of germination percentage was observed in Leptolyngbya sp. (11.63%) and C. sorokiniana (8.60%). Both strains improved early germination (3.78%), plumule length (33.88%), radical length (60.31%), fresh weight (7.97%) and dry weight (5.79%). (author)
[en] Bioenergy has gained great interest in the recent years for being environmentally friendly and renewable energy resource. Southern Thailand is well-known for agro-industry including rubber tree plantations and processing, which provide biomass that could be applied to produce bioenergy. Thus, this study aimed to investigate the energy potential of Rubber Wood Chips (RWC), Rubber Wood Pellets (RWP), Unburned Char (UBC) from rubber wood, blended RWC:UBC (50:50%) and blended RWP:UBC (50:50%). The physiochemical properties including bulk density, proximate composition, ultimate composition, heating value, Thermogravimetric Analysis (TGA), and lignocellulose content were determined for the biomass samples. The thermochemical conversion of biomass to syngas was performed using a downdraft gasifier operated at equivalence ratio 0.3. The results showed that the biomass was rich in carbon (content ranging from 44.77 to 58.54%) making it suitable for use as a solid fuel for gasification or combustion. The moisture contents of the biomass samples were below 10%. The contents of volatile matter in RWC and RWP were 74.40 and 75.40%, respectively. The UBC had a high fixed carbon content (50.60%) and comparatively low volatile matter (19%). The bulk densities of RWC, RWP and UBC were 193, 555 and 177 (kg/m3), respectively. The TGA showed the maximum weight loss of RWC and RWP around 400 °C, but this was at 800 °C for UBC. The higher heating values of RWC, RWP and UBC were 17.8 MJ/kg, 17.4 MJ/kg and 19.3 MJ/kg, respectively. The RWC and RWP had high cellulose and hemicellulose contents while UBC was rich in lignin. The syngas obtained from any of these biomass samples was mainly CO (10.81-22.67%) and CH4 (0.06-3.16%) with the lower heating value ranging from 2.78 to 4.72 MJ/Nm3. These results indicate that rubber wood biomass in various forms has relatively high potential for bioenergy applications via gasification, and it can help to support the renewable energy sector in Thailand. (author)
[en] The present study deals with the individual and combined effect of heavy metals and EMF. The treatments include different concentrations of lead and cadmium (250mm, 500mm and 750mm) which are selected as higher than permissible limits and other is an electromagnetic field (EMF). The effect of these stresses studied on the length of plant, the leaves number, biomass of plant and accumulation of lead and cadmium contents in mung bean seedlings (Vigna radiata). The results showed 500 and 750mm of lead and cadmium significantly decline plant height, the number of leaves and whole plant fresh and dry weight as in order (Cd 750mm> Cd 500mm>Pb750mm>Pb500mm), but a slight suppressed in all developing parameters and weight when exposed by EMF. Whereas, the combined treatment of lead+EMF and cadmium+EMF i.e 750mmCd +EMF>750mmPb + EMF cause a considerable decline in growth parameter and biomass of mung bean. In mung bean sequence of accumulation of lead and cadmium functioning as Cd 750mm> Cd 750mm EMF> Cd 500mm> Pb 750mm EMF> Pb 750mm. This significant building up of lead and cadmium content under single and combined treatment affected the growth factors of mung bean seedling. (author)
[en] Cosmic-ray neutron sensing: from noise to a well established method for non-invasive soil moisture estimation Cosmic ray neutron sensing (CRNS) has been introduced as a new non-invasive large scale method for soil moisture estimation. It is based on the inverse relationship between natural neutrons created by cosmic-ray and the presence of hydrogen at the land-surface, which is predominantly stored as water in the soil (Zreda et al., 2012). Noteworthy, this effect was well known by physicists with studies dating back more than half a century but it was considered as a noise (Hendrick and Edge, 1966). Only several years later, the use of natural neutron fluxes measured at the ground surface for quantifying soil moisture and snow water equivalent has been presented (Kodama et al., 1979). In these experiments, however, the neutron detector was installed below ground and the signal was strongly related to the hydrogen pools close to the probe. For this reason, this set-up probably did not provide relevant advantages in comparison to other point-scale soil moisture techniques (e.g., TDR) and it was considered for monitoring only extreme snowpack conditions (Morin, et al., 2012). In contrast, Zreda et al. (2012) showed that the signal of a neutron detector installed above-ground is sensitive to soil moisture within a large footprint of hundreds of meters horizontally and a soil depth of several decimeters. In such a way, they put CRNS in a new perspective proving to be a valuable technique to estimate soil moisture at an intermediate scale and showing to be a promising method with a range of applications. Above-ground CRNS method for soil moisture estimation is now used by several research groups all around the world and several national networks have been established. Most of the applications focus on detecting temporal soil moisture dynamics but promising results have been shown also as a rover for covering larger areas, for estimation biomass, water interception and large scale snow observations.
[en] Vermicomposting is the process of using worms to transform organic waste into a nutrient-rich fertilizer. The end product is called vermicast, which is used as fertiliser or as a soil activator. There are many advantages of vermicomposting, such as the improvement of soil aeration, enrichment of the soil with beneficial microorganisms, and increased water holding capacity, leading to better root growth and structure. All these positive effects are well documented. However, there are some studies suggesting that worms produce potent greenhouse gases (GHG), in particular nitrous oxide. Biochar (BC) addition to the studied soil-worm systems reduce the emissions. Biochar is similar to charcoal, basically it is pyrolysed biomass, specifically produced to be added to soil, as a soil conditioner-carbon sequestration measure. It has been recognised that vermicomposting could play a significant role in the circular economy, particularly tackling food waste recycling in peri-urban areas, whilst creating green business opportunities. To confidently advocate these novel systems, knowledge of the pollution swapping risks must be assessed. Therefore, a study was proposed to determine the influence of vermicompost on GHG emissions and the impact of adding biochar into the mix.