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Vermi-modification of ruminant excreta using Eisenia fetida Full text
2017
Sharma, Kavita | Garg, VinodKumar
Present investigation aims on the vermicomposting of the excreta of different ruminants to convert it into manure employing earthworm species, Eisenia fetida. A total of 11 feedstocks (FS₁–FS₁₁) with different ratios were prepared from the excreta of different ruminants, viz., sheep, cow, buffalo, and goat. Semi-composted feedstocks were fed to E. fetida for 90 days under laboratory conditions. Vermicomposting enhanced the nutrient contents of ruminant excreta and converted it into odor-free and homogenous vermicompost. The growth of E. fetida was significant in all the feedstocks, but largest biomass gain was achieved in buffalo excreta followed by [sheep + buffalo] > [goat + buffalo] and [cow + buffalo] feedstocks. Highest fecundity (782 ± 23.3) was also recorded in buffalo excreta followed by [goat + buffalo] excreta feedstock (484.6 ± 15.7). In vermicomposted feedstocks, total organic carbon and organic matter was lesser, while NPK and heavy metals were higher as compared to raw feedstocks. C/N ratios of vermicomposts ranged from 15.37 to 38.56, which indicate a good level of maturity and stabilization of feedstocks.
Show more [+] Less [-]Integrating ecosystem services in terrestrial conservation planning Full text
2017
Yuan, Mei-Hua | Lo, Shang-Lien | Yang, Zhikai
The purpose of this study is to estimate the benefits of ecosystem services for prioritization of land use conservation and to highlight the importance of ecosystem services by comparison between ecosystem service value and green GDP accounting. Based on land use pattern and benefit transfer method, this research estimated value of ecosystem services in Taiwan. Scientific information of land use and land cover change is accessed through multi-year satellite imagery moderate resolution imaging spectroradiometer (MODIS), and geographic information system (GIS) technology. Combined with benefit transfer method, this research estimated the ecosystem service valuation of forest, grassland, cropland, wetland, water, and urban for the period of 2000 to 2015 in Taiwan. It is found that forest made the greatest contribution and the significant increasing area of wetland has huge potential benefit for environmental conservation in Taiwan. We recommend placing maintaining wetland ecosystem in Taiwan with higher priority. This research also compared ecosystem service value with natural capital consumption which would essentially facilitate policy makers to understand the relationship between benefits gained from natural capital and the loss from human-made capital.
Show more [+] Less [-]Lanthanum-modified bentonite: potential for efficient removal of phosphates from fishpond effluents Full text
2017
Kurzbaum, Eyal | Raizner, Yasmin | Cohen, Oded | Rubinstein, Guy | Bar Shalom, Oded
Adsorption has been suggested as an effective method for removing phosphates from agricultural wastewater effluents that contain relatively high phosphate concentrations. The present study focused on the use of a bentonite-lanthanum clay (Phoslock®) for reducing the dissolved phosphate concentration in fishpond effluents. Batch experiments with synthetic phosphate-spiked solutions and with fishpond effluents were performed in order to determine adsorption equilibrium isotherms and kinetics as well as to determine the efficiency of Phoslock® in removing phosphate from these solutions. In the synthetic phosphate-spiked solution, the mean maximum phosphate adsorption capacity was 92 mg Phoslock®/mg phosphate removal. A ratio of 50, 100, and 200 mg Phoslock®/mg phosphate removal was found for complete phosphate removal from the fishpond effluents, where higher doses of Phoslock® led to a faster removal rate (94% removal within the first 150 min). These results show that bentonite-lanthanum clay can be employed for designing a treatment process for efficient phosphate removal from fishpond effluents.
Show more [+] Less [-]MiR-448 promotes vascular smooth muscle cell proliferation and migration in through directly targeting MEF2C Full text
2017
Zhang, Ruihong | Sui, Li | Hong, Xiaojian | Yang, Mao | Li, Weimin
Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) is a critical process in various cardiovascular diseases such as coronary artery disease (CAD), atherosclerosis, stroke, and hypertension. MicroRNAs (miRNAs) are small, short, and noncoding RNAs that inhibit gene expression through binding to the 3′-UTR (3′ untranslated regions) of target gene mRNAs. We showed that the expression of miR-448 was upregulated in VSMCs from coronary atherosclerotic plaques compared with normal coronary artery tissues. We also found that PDGF-bb promoted VSMCs proliferation and could induce miR-448 expression. Ectopic miR-448 expression induced VSMCs proliferation. Overexpression of miR-448 induced ki-67 mRNA and protein expression. Moreover, we identified MEF2C was a direct target of miR-448 in VSMCs. Overexpression of miR-448 promoted VSMCs migration. Furthermore, overexpression of MEF2C decreased miR-448-induced VSMCs proliferation and migration. These evidences suggested that miR-448 played an important role in the proliferation and migration of VSMCs.
Show more [+] Less [-]Fractions and transformation of organic phosphorus in sediments from a eutrophic lake in China Full text
2017
Hezhong, Yuan | Liang, Zhen | Enfeng, Liu | Qi, Lin | Cheng, Wang | Enlou, Zhang
Several organic phosphorus compounds (Po) in sediment from a representative eutrophic lake were surveyed using a sequential fractionation procedure, which included microbial biomass phosphorus (Biomass-P), fulvic acid phosphorus (FA-P), humic acid phosphorus (HU-P), and residual phosphorus (Res-P). In addition, several organic compounds including orthophosphate monoesters, orthophosphate diesters, and pyrophosphate were simultaneously measured using ³¹P nuclear magnetic resonance (³¹P NMR). Results showed that Po contributed over 50% of total phosphorus (TP), and the average concentration of Po species generally decreased from Res-P > FA-P > HU-P > Biomass-P. Additionally, the relative proportions of phosphorus compounds in the sediment followed the decreasing order of orthophosphate monoesters > orthophosphate diesters > pyrophosphate. In general, Po was the dominant phosphorus species. Residual P was not a single species but comprised of a group of species, and tended to be stable. Although orthophosphate monoesters had the highest concentrations and ratios in Po, orthophosphate diesters displayed a more distinct remineralization trend. Principal component analysis (PCA) coupled with correlation analysis suggested that a greater amount of orthophosphate diesters resided in Res-P, than HU-P or FA-P.
Show more [+] Less [-]Studies on acute and chronic toxicity of cadmium to freshwater snail Lymnaea acuminata (Lamarck) with special reference to behavioral and hematological changes Full text
2017
Dhara, Kishore | Saha, Nimai Chandra | Maiti, Arpan Kumar
Molluscs have long been regarded as promising bioindicator and biomonitoring subjects for heavy metals as molluscs are highly tolerant to heavy metals and exhibit high accumulation in their body. In spite of several previous studies about the impact of cadmium on molluscs, little information exists in literatures concerning the toxic effects of cadmium on Lymnaea acuminata, especially pertaining to behavioral and hematological changes as these are considered effective bioindicators and biomonitoring variables for detecting heavy metals in polluted water bodies. In the present study, the median lethal concentrations of cadmium chloride to snail, Lymnaea acuminata, were estimated to be 9.66, 7.69, 6.26, and 5.54 mg/L at 24, 48, 72, and 96 h, respectively. For behavioral studies, variable test concentrations of cadmium from 0.00 to 10 mg/L were used. The clumping tendency, crawling activity, and touch reflex in the exposed snails were gradually decreased with higher concentrations at 72 and 96 h. For measuring the hemocyte numbers in the circulating hemolymph of snail during chronic cadmium exposure, two sublethal doses of cadmium (10 and 20% 96-h LC₅₀—0.55 and 1.11 mg/L, respectively) were used. A significant variation (p < 0.05) from the control at all exposure times (7, 14, 21, and 28 days) was recorded at 1.11 mg/L concentration. The total count of circulating hemocytes was significantly reduced (p < 0.05) compared to the controls at both concentrations of cadmium exposure at all time periods except 14 and 21 days exposure at 0.55 mg/L where values were non-significantly increased. In comparison between two sublethal doses, blood cells were significantly (p < 0.05) lowered at 1.11 mg/L cadmium treatment. Considering the behavioral and hematological data, it seems possible to forecast the physiological state of snails in cadmium-contaminated water bodies and these findings can be used in determining the safe disposal level of cadmium in aquatic ecosystem.
Show more [+] Less [-]Titanium tetrachloride for silver nanoparticle-humic acid composite contaminant removal in coagulation-ultrafiltration hybrid process: floc property and membrane fouling Full text
2017
Zhao, Yanxia | Sun, Yangyang | Tian, Chang | Gao, Baoyu | Wang, Yan | Shon, Hokyong | Yang, Yanzhao
Titanium-based coagulation is expected to achieve both efficient water purification and sludge recycling. This study is the first attempt to use titanium tetrachloride (TiCl₄) for silver nanoparticle (AgNP)-humic acid composite contaminant removal in a coagulation-ultrafiltration (C-UF) process, where characterization of flocs and membrane fouling under varied coagulant dose, initial solution pH, and AgNP concentration conditions are the main contents. Results suggested that the TiCl₄ achieved high AgNP removal in the form of silver nanoparticle through adsorption and sweep flocculation and simultaneously exerted additional 68.2 % higher dissolved organic carbon removal than Al₂(SO₄)₃. The TiCl₄ produced larger and stronger flocs but with weaker recoverability and less compact degree than did Al₂(SO₄)₃. Floc properties were independent of AgNP concentration except floc fractal dimension, which was negatively correlated with AgNP concentration. The TiCl₄ precoagulation caused less membrane fouling within wider pH range than Al₂(SO₄)₃ did in the C-UF process. Incorporation of AgNPs during the TiCl₄ pretreatment process facilitated the mitigation of membrane fouling, which was, however, negligibly influenced by AgNP concentration in the case of Al₂(SO₄)₃.
Show more [+] Less [-]Global warming potential and greenhouse gas emission under different soil nutrient management practices in soybean–wheat system of central India Full text
2017
Lenka, Sangeeta | Lenka, Narendra Kumar | Singh, Amar Bahadur | Singh, B. | Raghuwanshi, Jyothi
Soil nutrient management is a key component contributing to the greenhouse gas (GHG) flux and mitigation potential of agricultural production systems. However, the effect of soil nutrient management practices on GHG flux and global warming potential (GWP) is less understood in agricultural soils of India. The present study was conducted to compare three nutrient management systems practiced for nine consecutive years in a soybean–wheat cropping system in the Vertisols of India, in terms of GHG flux and GWP. The treatments were composed of 100% organic (ONM), 100% inorganic (NPK), and integrated nutrient management (INM) with 50% organic + 50% inorganic inputs. The gas samples for GHGs (CO₂, CH₄, and N₂O) were collected by static chamber method at about 15-day interval during 2012–13 growing season. The change in soil organic carbon (SOC) content was estimated in terms of the changes in SOC stock in the 0–15 cm soil over the 9-year period covering 2004 to 2013. There was a net uptake of CH₄ in all the treatments in both soybean and wheat crop seasons. The cumulative N₂O and CO₂ emissions were in the order of INM > ONM > NPK with significant difference between treatments (p < 0.05) in both the crop seasons. The annual GWP, expressed in terms of CH₄ and N₂O emission, also followed the same trend and was estimated to be 1126, 1002, and 896 kg CO₂ eq ha⁻¹ year⁻¹ under INM, ONM, and NPK treatments, respectively. However, the change in SOC stock was significantly higher under ONM (1250 kg ha⁻¹ year⁻¹) followed by INM (417 kg ha⁻¹ year⁻¹) and least under NPK (198 kg ha⁻¹ year⁻¹) treatment. The wheat equivalent yield was similar under ONM and INM treatments and was significantly lower under NPK treatment. Thus, the GWP per unit grain yield was lower under ONM followed by NPK and INM treatments and varied from 250, 261, and 307 kg CO₂ eq Mg⁻¹ grain yield under ONM, NPK, and INM treatments, respectively.
Show more [+] Less [-]Cd inhibition and pH improvement via a nano-submicron mineral-based soil conditioner Full text
2017
Liu, Shanke | Li, Huan | Han, Cheng | Sheng, Xuebin | Liu, Jianming
Cd contamination of rice in recent years has aroused a nationwide concern on the potential health risk to people in China. A significant increase of soil acidification in major Chinese croplands improves available Cd content by crops, and this further pushes a heavier burden on controlling Cd contamination. Therefore, it is urgent to find a workable and green way to control Cd contamination, i.e., decrease Cd content in rice, for people’s health in China, as other countries in the world. From chemical and economic points, stabilizing/solidifying Cd may be a feasible way except in-situ ways such as removing it by the absorption of special plants and ex-situ ones such as removing the contaminated soil and treating it by special equipment. Then, it is very important how to choose a green solidifying agent. By simulating a rock-weathering process, a nano-submicron mineral-based soil conditioner (NSC) was prepared through environmentally friendly hydrothermal reaction. The application of NSC not only decreased Cd content in rice, i.e., inhibited Cd absorption, and increased pH of the soil, but also improved the content of healthy nutrients such as organic matter, available Ca, available K, available P, and available Si in the soil. The mechanism why NSC showed such good performance was also discussed in this study.
Show more [+] Less [-]Distributions and sources of heavy metals in sediments of the Bohai Sea, China: a review Full text
2017
Duan, Xiaoyong | Li, Yanxia
This paper summarizes the recent research results from studies concerning heavy metals in the Bohai Sea in recent decades. The temporal and spatial variations and potential sources of the heavy metals in the surface sediments were analyzed. Based on these obtained data, the average concentrations in surface sediments collected in recent years (summarized 3171 samples) were 0.31, 87.0, 25.7, 25.8, 0.11, 16.9, 52.2, and 27.7 μg/g for Cd, Zn, Cu, Pb, Hg, As, Cr, and Ni, respectively. In the samples collected in the 1980s, the concentrations were 22.6, 21.3, 69.13, 0.26, and 57.5 μg/g (summarized 218 samples) for Cu, Pb, Zn, Cd, and Cr. The concentrations of Cu, Pb, Zn, and Cd increased slightly. Generally, higher concentrations were measured in the Bohai Bay and central Bohai Sea. The distribution patterns of heavy metals were significantly different between samples collected after the year of 2000 and those in the 1980s. In the 1980s and recent years, higher concentrations of Zn, Cd, and Pb were measured in the samples collected from Bohai Bay and Liaodong Bay, respectively. This indicated that the sources of heavy metals in Bohai Sea were changed significantly during the past decades.
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