Effect of Biosolid Amendments on the Metal and Nutrient Uptake and Spectral Characteristics of Five Vegetable Plants

The accumulation of metals and nutrients in biosolid-amended soils and the risk of their excess uptake by plants is a topic of great concern. This study examines the elemental uptake and accumulation in five vegetable plants grown on biosolid-applied soils and the use of spectral reflectance to monitor the resulting plant stress. Soil, shoot, root, and fruit samples were collected and analyzed for several elemental concentrations. The chemical concentrations in soils and all the plant parts increased with increase in applied biosolid concentrations. The Cu and Zn concentrations in the plant shoots increased in the order of collard<radish<lettuce<tomato<pepper. The Cu and Zn concentrations accumulated significantly in the fruits of the tomato plants compared to other plants. Among all the plants, the shoot concentration factor (SCF) of Zn was significantly higher for pepper plants, indicating increase in uptake of Zn. The shoot relative uptake index (SRUI) of Cu and Zn increased in the order of collard<radish<lettuce<tomato<pepper. The shoot dry weight and spectral reflectance of the radish plants in the near-infrared (NIR) region (800-1,300 nm) decreased significantly with increase in biosolid concentration compared to other plants. Increase in plant stress with increase in biosolid dose was evident in radish plants through significant reduction in Normalized Difference Vegetative Index (NDVI). This study indicates the potential use of spectral reflectance as a tool for the screening and monitoring of stress-sensitive plant species and their physiology and as a result, indirectly assesses the chemical concentrations in soils and plants

Effect of Bioaccumulation of Cs and Sr Natural Isotopes on Foliar Structure and Plant Spectral Reflectance of Indian Mustard (Brassica juncea) -8105

ABSTRACT The objectives of this study are: 1.) evaluate the capacity of Indian mustard (Brassica juncea) for uptake and accumulation of Cs and Sr natural isotopes; 2.) identify foliar structural and other physiological changes (biomass, relative water content, etc.) resulting from the accumulation of these two elements; and 3.) monitor Cs and Sr uptake and bioaccumulation process by spectral reflectance. Potted Indian mustard plants were exposed to different concentrations of Cs (50 and 600 ppm) and Sr (50 and 300 ppm) natural isotopes in solution form for 23 days. Bioaccumulation of Cs and Sr was found in the order of leaves &gt; stems &gt; roots for both Cs-and Sr-treated plants. The highest leaf Sr accumulation is observed to be 2708 mg kg -1 , and the highest leaf Cs accumulation is 12251 mg kg -1 . High translocation efficiency for both elements is documented by shoot/root concentration ratios greater than one. Relative water content (RWC) of the plants showed a significant (p &lt; 0.05) decrease in Cs-treated plants. Cs accumulation also affected the pigment concentration and internal structure of the leaf and the spectral characteristics of plants. Within the applied concentration range, Sr accumulation resulted in no significant changes in RWC, structural and spectral characteristics of mustard plants. Cs shoot concentration showed significant negative correlation with relative water content RWC (r = -0.88) and Normalized Difference Vegetation Index (NDVI) (r = -0.68) of plant shoots. The canopy spectral reflectance and NDVI analysis clearly revealed (p &lt; 0.05) the stress caused by Cs accumulation

Matrix Hybridization Effects on Interlaminar Fracture Toughness of Glass Epoxy Laminates using Nano and Micro fillers

The composite materials are normally made of reinforcements and resins. High-performance composites are generally termed hybrid composite materials. Generally, fiber-reinforced composite laminates are very weak in their out-of-plane properties, to address this issue unidirectional (UD) Glass laminates are prepared by modifying epoxy matrix using plasma-treated multi-walled carbon nanotubes (MWCNTs) and compared with low-cost micro fillers like Aluminum oxide (Al2O3) and Sodium Carbonate (Na2CO3) in the epoxy matrix. All these Nano and Micro fillers were loaded in the range of 0.5wt% to 2wt% in epoxy. The addition of these fillers in the epoxy matrix was found to be effective in increasing the out-of-plane load-bearing capacity of the composites as compared to plain Glass epoxy laminates. Also, the fracture toughness enhanced in the range of 20-26% and 14-17.5% under mode I and mode II loading respectively. Scanning electron microscopic analysis was done for delaminated glass laminates and found that the delamination of fibers is the significant failure mechanism during crack initiation from the crack tip

Matrix Hybridization Effects on Interlaminar Fracture Toughness of Glass Epoxy Laminates using Nano and Micro fillers

The composite materials are normally made of reinforcements and resins. High-performance composites are generally termed hybrid composite materials. Generally, fiber-reinforced composite laminates are very weak in their out-of-plane properties, to address this issue unidirectional (UD) Glass laminates are prepared by modifying epoxy matrix using plasma-treated multi-walled carbon nanotubes (MWCNTs) and compared with low-cost micro fillers like Aluminum oxide (Al2O3) and Sodium Carbonate (Na2CO3) in the epoxy matrix. All these Nano and Micro fillers were loaded in the range of 0.5wt% to 2wt% in epoxy. The addition of these fillers in the epoxy matrix was found to be effective in increasing the out-of-plane load-bearing capacity of the composites as compared to plain Glass epoxy laminates. Also, the fracture toughness enhanced in the range of 20-26% and 14-17.5% under mode I and mode II loading respectively. Scanning electron microscopic analysis was done for delaminated glass laminates and found that the delamination of fibers is the significant failure mechanism during crack initiation from the crack tip

Transfer of wastewater associated pharmaceuticals and personal care products to crop plants from biosolids treated soil

The plant uptake of emerging organic contaminants such as pharmaceuticals and personal care products (PPCPs) is receiving increased attention. Biosolids from municipal wastewater treatment have been previously identified as a major source for PPCPs. Thus, plant uptake of PPCPs from biosolids applied soils needs to be understood. In the present study, the uptake of carbamazepine, diphenhydramine, and triclocarban by five vegetable crop plants was examined in a field experiment. At the time of harvest, three compounds were detected in all plants grown in biosolids-treated soils. Calculated root concentration factor (RCF) and shoot concentration factor (SCF) are the highest for carbamazepine followed by triclocarban and diphenhydramine. Positive correlation between RCF and root lipid content was observed for carbamazepine but not for diphenhydramine and triclocarban. The results demonstrate the ability of crop plants to accumulate PPCPs from contaminated soils. The plant uptake processes of PPCPs are likely affected by their physico-chemical properties, and their interaction with soil. The difference uptake behavior between plant species could not solely be attributed to the root lipid content. (C) 2012 Elsevier Inc. All rights reserved.The plant uptake of emerging organic contaminants such as pharmaceuticals and personal care products (PPCPs) is receiving increased attention. Biosolids from municipal wastewater treatment have been previously identified as a major source for PPCPs. Thus, plant uptake of PPCPs from biosolids applied soils needs to be understood. In the present study, the uptake of carbamazepine, diphenhydramine, and triclocarban by five vegetable crop plants was examined in a field experiment. At the time of harvest, three compounds were detected in all plants grown in biosolids-treated soils. Calculated root concentration factor (RCF) and shoot concentration factor (SCF) are the highest for carbamazepine followed by triclocarban and diphenhydramine. Positive correlation between RCF and root lipid content was observed for carbamazepine but not for diphenhydramine and triclocarban. The results demonstrate the ability of crop plants to accumulate PPCPs from contaminated soils. The plant uptake processes of PPCPs are likely affected by their physico-chemical properties, and their interaction with soil. The difference uptake behavior between plant species could not solely be attributed to the root lipid content. (C) 2012 Elsevier Inc. All rights reserved