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Machine Learning Model for Revealing the Characteristics of Soil Nutrients and Aboveground Biomass of Northeast Forest, China
2020
Chunyan Wu, Lifeng Pang, Jun Jiang, Miaoying An , Yuanjun Yang
Declining soil quality and climate change may affect species diversity and forest biomass productivity in many temperate regions in the future. Our research objective is to reveal the characteristics of soil nutrients and biomass of forests in Northeast China with climate change. The purpose of this study was to determine the soil physical and chemical properties of mature broad-leaved forest in the cold temperate zone of Mt. Changbai, Jilin Province, by measuring pH, NH4 +, organic matter (%), C/N, available phosphorus, alkali-hydrolysable N, rapidly available K, and Cr etc., analysing species diversity characteristics, and estimating aboveground biomass (AGB) of tree species with machine learning models. The results showed that with the increase of soil depth, the soil physical and chemical parameters have a decreasing trend; with the increase of soil depth, the soil nutrient content decreased; the main tree species were the Acer barbinerve (6937), Carpinus cordata Bl. (6682) and Acer mandshuricum Maxim. (5447) etc. The total difference (SOR) showed a similar trend in the four directions and central point; the reference sample size at central point, north, west, south and east direction was 903, 954, 971, 1005 and 1016, respectively; GRNN model was the relatively best model among these models for modelling the aboveground biomass of the trees. Therefore, the diversity of tree species in north-eastern forests was affected by soil nutrients, climate change also has a significant impact on the aboveground biomass of northeast forests, which provides a theoretical basis for the management of northeast forests about soil physical and chemical properties and species diversity.
اظهر المزيد [+] اقل [-]Hydrolithological Investigation for Near-Surface Aquifers Within Lekki Peninsula, Lagos, Southwestern Nigeria
2020
O. G. Bayowa, T. A. Adagunodo, O. A. Olaleye, A. E. Adeleke, M. R. Usikalu , S. A. Akinwumi
This study is aimed at investigating the near-surface aquifers within Lekki Peninsula, Lagos, Southwestern Nigeria. Thirty-one (31) Vertical Electrical Sounding (VES) data were acquired using the Schlumberger array with current electrode spacing, which varies between 1 and 400m. The VES data were quantitatively interpreted, and the final layer parameters obtained were used to generate 2D geoelectric sections. Litho-logs acquired within the Lekki Peninsula were used to correlate the geoelectric sections to understand the nature and depth of groundwater contained in each aquiferous zone. The lithologies delineated in the study area include the topsoil (fill and/or sand) with resistivity value, which varies between 39 and 1535Wm as well as layer thickness from 0.5 to 5.5m; second layer of wet clay/sandy clay (saturated with brackish water) with resistivity value, which varies between5 and 163Wm as well as layer thickness from 1.5 to 10m; third layer of clayey sand/sand (saturated with freshwater) with resistivity value, which varies between 10 and 898Wm as well as layer thickness value from5 to 34m; and fourth layer of clay (saturated with saline water) with resistivity value, which varies between 1 and 9Wm. Isolated sand bodies (probably unsaturated zone) with resistivity value, which varies from 648 to 3560 Wm, were delineated beneath VES stations 24, 25, 29 and 30. The study concludes that the topsoil (sand/fill), unsaturated zone (conglomerate), silty mud layer (brackish/ freshwater saturated), and sand layer (saline water-saturated) constitute the aquifers and water quality within Lekki Peninsular. The inhabitants of the study area are, therefore, advised to avoid absurd usage of water to reduce the pumping rate and intrusion into the saline water formation.
اظهر المزيد [+] اقل [-]Capital Allocation Efficiency Evaluation of Energy Conservation and Environmental Protection Enterprises in the Yangtze River Delta of China
2020
Hongjun Xiong
Various measures are implemented to promote the construction of China’s ecology. These measures aim to accelerate the green transformation of the economy and promote the rapid development of energy conservation and environmental protection industry under the promotion of relevant policies. Consequently, the numbers of enterprises and the market scale have shown explosive growth. However, energy conservation and environmental protection enterprises are faced with lack of technological innovation, shortage of capital, and high cost. Effective measures must optimize the efficiency of capital allocation. To evaluate the capital allocation efficiency of energy conservation and environmental protection enterprises, 26 listed companies of energy conservation and environmental protection in the Yangtze River Delta of China were selected as samples. Monetary capital, accounts receivable, inventory, fixed assets, and construction in progress were used as input scalars. Net profit, undistributed profit, and surplus reserve were used as output variables. The Data Envelopment Analysis (DEA) model was used for analysis. Results show that capital allocation efficiency of 11 sample companies is DEA-effective. Power, heat, gas, water production, and supply industry rank first with the real estate industry divided by industry. Shanghai ranks first in the regional division. Specific improvement strategies are proposed for non-DEA effective sample enterprises.
اظهر المزيد [+] اقل [-]Lithium Induced Toxicity Profile of Oxygen Consumption, Haematological Parameters and Biochemical Profiles of Channa punctatus and Oreochromis niloticus
2020
S. ThangaMalathi , V.Anuradha
Freshwaters are highly vulnerable to pollution since they act as immediate sinks for the consequences of human activity always associated with the danger of accidental discharges. Heavy metals constitute a core group of aquatic pollutants and additional concentrations of these metals accumulate in the aquatic ecosystems as a result of land-based activities. Fish mostly tend to bioaccumulate heavy metals, and humans can be at great risk, sometimes even lethal, through contamination of the food chain. An attempt has been made in the present investigation to determine the acute toxicity of lithium and its toxicological effects on survival, physiological, haematological and biochemical parameters of the widely consumed spotted sneak head Channa punctatus and Nile Tilapia Oreochromis niloticus. Short-term acute toxicity tests were performed by exposing the test species to different concentrations of lithium chloride. The results showed that the normal respiratory activity of the fish was significantly affected and there was a depression in the metabolic rate at the end of 24, 48, 72 and 96h exposure. Appreciable decline changes occur in haematological parameters and biochemical profiles of the fish. This study reflects the extent of the toxic effects of lithium and the metal-induced cumulative deleterious effects at various functional levels in the widely consumed freshwater fish, Channa punctatus and Oreochromis niloticus.
اظهر المزيد [+] اقل [-]Application of Recycled Coarse Aggregate in Steel Tubular Members
2020
Gajalakshmi Pandulu, Revathy Jayaseelan , Mohana Priya
Recycled aggregate from the demolition of buildings provides a sustainable solution in reducing the space required for dumping demolished waste as landfill and also reduces the consumption of natural aggregate. A percentage of recycled coarse aggregate can be used in structural members which can be economical and environmentally useful. This experimental study consists of three phases. In Phase I, an attempt was made to use Recycled Coarse Aggregate (RCA) in place of Natural Coarse Aggregate(NCA) in concrete. Experimental results of concrete for various combinations of RCA with NCA wereanalysed numerically for the optimum value using Taguchi’s method. In Phase II, the confirmation study was conducted to study the strength and durability characteristics of concrete made with the optimized value of recycled aggregate. In Phase III, the application of optimized recycled coarse aggregate concrete was done by conducting a study on the load-carrying capacity of recycled coarse aggregate concrete-filled steel tube members. The results revealed that there is a marginal increase in load-carrying capacity of recycled coarse aggregate concrete-filled steel tube members than natural coarse aggregate concrete-filled steel tube members. This application proves to be ecofriendly and environmentally sustainable by using the demolished concrete in the structural member.
اظهر المزيد [+] اقل [-]Inhibition of Mild Steel Corrosion in Hydrochloric Acid Solution by Leaves of Ziziphus jujuba
2020
Rakesh Kumar Dubey, Nitin Gupta, S. M. Nafees , Kalpana S.
Weight loss method was used to assess the inhibition of mild steel corrosion in 1M HCl solution with aqueous extract of Ziziphus jujuba leaves at 303 to 333K temperatures. It was found that Ziziphus jujuba leaves extract retarded the dissolution of mild steel in 1M HCl solution. The inhibition efficiency increases with a rise in the concentration of extract and decreases with increase in temperature. Maximum 88.54% inhibition efficiency was observed at 303 K and 8% (v/v) composition of the extract. Adsorption of extract at mild steel surface follows Langmuir adsorption isotherm. Values of Gibbs free energy, variation in inhibition energy with temperature and with activation energy values trend proposed the physisorption. Negative values of Gibbs energy propose the spontaneous process of inhibition process in the extract at studied temperatures.
اظهر المزيد [+] اقل [-]Experimental Study on Transport of Carboxylate Polystyrene Microspheres, Using as a Cryptosporidium Oocysts Surrogate, with Runoff from the Slope Soil to the Surface Water Bodies
2020
Tao Yuan, Sen Cheng, Lai Zhou, Qiyan Feng , Ping Lu
Cryptosporidium can transport from the soil to the water resulting in the contamination of the surrounding water bodies. However, there are few pieces of research on the transport of Cryptosporidium from the slope soil to the surrounding water. The experiment simulated the transport of Cryptosporidium surrogate, carboxylate YG polystyrene, influenced by the rainfall intensity, rainfall pattern, soil type, and land slope, from the soil to water, to understand the transport of Cryptosporidium surrogate under these different conditions. The results showed that the transport of Cryptosporidium surrogate was affected by the surface runoff factors, that is, the high rainfall intensity, high rainfall frequency, steep slope and high sand content soil that resulted in the high transport of the Cryptosporidium surrogate.
اظهر المزيد [+] اقل [-]Measurement of Tourism Industry-Ecological Environment Coupling Degree and Management and Control Measures for Tourism Environment: A Case Study of Henan Province, China
2020
Yan Fei Shen
The tourism industry has the largest scale of economic activities worldwide with the most powerful development momentum but has generated a negative effect on the ecological environment. The development of the tourism industry is a precondition and guarantee of eco-environmental optimization, and a harmonious ecological environment is an important dynamic support for the growth of tourism economy, making them mutually associated with evident coupling characteristic. In this study, related literature regarding the tourism industry and eco-environmental protection of developed countries in Europe and America were first reviewed, and tourism industry-ecological environment coupling model was constructed using Henan Province, China, as a case study. The coupling degrees in Henan Province during 2013-2018 were measured, and a comparative analysis of the spatial changes in tourism industry-ecological environment coupling degrees of 18 prefecture-level cities in Henan in 2013 and 2018 was conducted. Results showed that the order degree of the tourism industry in Henan Province maintained a rising trend during 2013-2018, whereas that of the ecological environment exhibited a fluctuating trend. The overall tourism industry–ecological environment coupling of 18 prefecture-level cities in Henan Province enhanced in 2013 and 2018, where the coupling degrees in Zhengzhou, Nan yang, and Luoyang presented an outward radiation trend from high to low. The study results serve as significant reference values for revealing the spatial-temporal evolution characteristics of the ecological environment and the tourism industry and completing the research regarding the coordinated development of the tourism industry and ecological environment.
اظهر المزيد [+] اقل [-]Impact of Environmental Investment on Performance of Intelligent Manufacturing Enterprises in the Yangtze River Delta of China
2020
Wanqing Shao
The rapid development of information technology has promoted the transformation of the manufacturing industry and the upgrading of Chinese intelligent manufacturing enterprises. Environmental protection and enterprise benefits have become the pursuit target. To explore the impact of environmental investment on the performance of intelligent manufacturing enterprises, an evaluation index system from the four dimensions of debt paying, operation, profitability, and growth ability was constructed. Then, factor analysis method was used to analyse the index data of 33 intelligent manufacturing enterprises in the Yangtze River Delta in 2018, and a multiple regression model was constructed to analyse the impact of environmental investment on enterprise performance. Results show a significant difference in the performance of intelligent manufacturing enterprises in the Yangtze River Delta and a positive correlation between environmental investment and enterprise performance. Finally, specific optimization measures are given to help the managers of intelligent manufacturing enterprises make scientific and reasonable decisions.
اظهر المزيد [+] اقل [-]Comparative In Vitro Assessment of Hydrocarbon Degradation Potential of Pleurotus ostreatus MP 5 and Pleurotus ostreatus MTCC 1804
2020
Madhavi Tiwari, Ashish Saraf and Meghna Shrivastava
Mycoremediation, involving the use of fungus for bioremediation, is one of the promising cost-effective methods for cleaning up the carcinogenic and mutagenic polycyclic aromatic hydrocarbons present in the environment. The present study deals with the isolation of white rot fungus from Chhattisgarh forest, India followed by identification based on ITS sequencing. Identification revealed MP 5 closely related to Pleurotus ostreatus isolate 6689 with 99% sequence similarity. Comparative primary screening assay of both the wild isolate and reference strain of Pleurotus ostreatus MTCC 1804 was performed by measuring the growth diameter of mycelia on minimal salt media enriched with 2% used engine oil (v/v). The fungal isolate MP 5 showed highest average growth rate. Confirmatory test was conducted via orbital shaking method and spectroscopic study was carried out at 600 nm which displayed degradation within 7 days and percentage of degradation was calculated. Level of degradation was 69.7 ± 0.351% and 64.7 ± 1.153% respectively for Pleurotus ostreatus MP 5 and Pleurotus ostreatus MTCC 1804. Degradation potential of both the isolates was evaluated in terms of chemical characterization via Fourier transform infrared spectroscopy (FTIR) which revealed bands formation based on the presence of different functional groups indicating oxidative degradation of hydrocarbons.
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