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Sewage sludge (SS) is a source of nutrients, and it improves the physical, chemical, and biological properties of soil, thereby increasing crop productivity. Accordingly, this study was aimed to evaluate the growth and development of the silver vase bromeliad (Aechmea fasciata) cultivated in a substrate with different doses of SS. To accomplish this, silver vase bromeliad plants were cultivated for 120 days in pots containing pine bark as a substrate with varying doses of solid SS (0, 18, 36, 54, or 72 g SS L−1). The experiment was carried out in a completely randomized block design, comprising five treatments and four replications, with four plants per pot, totaling 80 plants. Substrate fertilization with SS improved the nutritional status as well as the physiological and morphological parameters of the silver vase bromeliad. Fertilization with 72 g SS L−1 added to pine bark resulted in the best outcomes for plant height and the number of leaves. [ABSTRACT FROM AUTHOR]

Bark is a large-tonnage waste in a number of wood processing technologies requiring efficient use. One of the promising areas of bark use is the production of boards without synthetic binders. Research has been conducted on the production of structural boards from Pinus sylvestris bark without a binder. The method is based on preliminary hydrodynamic activation of bark. The initial bark undergoes primary crushing in a hammer mill. After that, it is mixed with water at a concentration of 6 %. Then the resulting mass is activated in a rotary pulsation disperser, a carpet is formed from it, cold pressing is carried out, and then hot pressing. As a criterion for assessing the degree of mass activation, water-retaining capacity is adopted. The dependencies have been determined between the duration of treatment and water-retaining capacity, as well as the strength of the boards and water-retaining capacity. The latter made it possible to obtain the optimal value of the water-retaining capacity equal to 290 %. A multifactorial experiment has been conducted to develop the optimal hot pressing mode. As a result, the optimal mode for pressing the boards has been determined: temperature – 190 °C; specific process duration – 2.8 min/mm; pressing pressure – 4.4 MPa. The properties of the boards produced in this mode are: density – 980 kg/m 3 ; bending strength – 24 MPa; swelling during soaking for 24 hours – 5 %; water absorption – 9 %. After soaking and subsequent drying to a moisture content of 5 %, the boards retain 75 % of their before soaking. In this case, the geometric dimensions return to the original ones. The resulting boards can be used as a sheet finishing and structural material, in house-building (as a base for floor and roofing materials), in furniture production, especially in severe temperature and humidity conditions. The conducted research shows the possibility of producing board materials with high performance properties from pine bark without binders.

Bulk density (Db) and subsequent physical properties are determined by the substrate and packing method. Packing method is the way one fills and compresses a substrate within a given volume. Bulk density produced in the laboratory may not align with “expected” published ranges due to variations in packing. Additionally, it is unknown if ranges identified as “typical” using a small volume sample ring reflect Db occurring in larger production size containers packed using commercial potting practices. Therefore, our objectives were to 1) emulate nursery practices and document the Db associated with a potted 2.8-L (#1) container, 2) develop and test the new “shim and compression” method to determine if it consistently packs sample rings to a Db commensurate with that of a 2.8-L nursery container, and 3) demonstrate how static physical properties are affected by the new “shim and compression” sample ring packing method compared with the traditional bench top tap method. When emulating nursery potting practices with 100% pine bark, coir, and peat, and blends of each, Db ranged from 0.08 g.cm-3 (coconut coir) to 0.17 g.cm-3 (pine bark). We used an espresso tamp and shims to pack the aforementioned substrates in sample rings. The Db achieved using a range in number of presses and discs was largely dependent on the substrate, but the desired Db was consistently achieved for each substrate. There was no effect of disc number on Db (P 5 1.000) for any substrate. There was no effect of tamp number (P $ 0.0602) for all substrates except peat-amended, for which five tamps yielded a greater Db than one tamp (P 5 0.0324). In an experiment in which a different technician who was accustomed to the conventional benchtop tap packing method performed both methods, method influenced Db (P < 0.0001), and the conventional method more closely attained the target Db. To our knowledge, this is the only report of Db observed in commercial container production facilities (i.e., “native”). [ABSTRACT FROM AUTHOR]

In this study, a total of 180 Pinus eldarica bark samples were collected from different regions of Hamedan megacity, Iran, in 2023, and contents of Cd, Cr, Cu, Mn, Ni, Pb, and Zn in the samples were determined using ICP-OES. The results illustrated that the average contents of all the analyzed elements were greater than those in the background contents, which presumably demonstrated anthropogenic sources of these potentially toxic elements (PTEs). The greatest concentrations of the analyzed PTEs for different functional areas were observed in specimens collected from commercial or industrial areas, indicating the impact of human entries. The I-geo values were in the range of "unpolluted to moderately polluted" to "moderately to heavily polluted", PI showed "moderate to very high pollution", and PLI reflected high to very high pollution levels for the whole study area. Additionally, the cumulative mean value of ecological risk (RI) was found to be 152, demonstrating moderate ecological risk across the study area. The results of positive matrix factorization (PMF) showed that the PTE contamination in the air of Hamedan could mainly have an anthropogenic origin (82.7%) and that the traffic emissions as the primary pollution source (33.6%) make the highest contribution to the PTE pollution and ecological risks in the study area. In residential areas, demolition and construction activities could be considered the main sources of PTEs, while in commercial and industrial areas traffic emissions and industrial emissions, could be regarded as the main sources of such pollution, respectively. In conclusion, this study provides a useful approach to identifying the sources and contributions of the toxic elements in different functional areas and can inform future endeavors that aim at managing and controlling metal element pollution. [ABSTRACT FROM AUTHOR]

This study explored the potential application of polyphenols from Pinus halepensis bark in leather tanning. The primary objective was to characterize these polyphenols. The extraction and atomization processes proved efficient, reducing moisture content to 7.4%, increasing tannin content from 26.2% to 45.1%, and reducing insoluble substances by 77.5%. High-performance liquid chromatography (HPLC) coupled with mass spectrometry identified and quantified various polyphenolic compounds, including (+)-catechin, (+)-taxifolin, protocatechuic acid, and procyanidin B2. Notably, tannic catechin dimers were detected. Lignin was effectively removed through filtration. Concentrations of protocatechuic acid, (+)-catechin, (+)-taxifolin, (−)-epicatechin, and procyanidin B1 were significantly higher in the extract than in the powder, with the extract showing 1214.3 mg/kg of protocatechuic acid, 2098.0 mg/kg of (+)-catechin, 4017.0 mg/kg of (+)-taxifolin, 2163.0 mg/kg of (−)-epicatechin, and 917.0 mg/kg of procyanidin B1. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the influence of organic amendments (OAs) on neutralizing the harmful effect of copper (Cu) on black mustard (Sinapis nigra L.). In a pot experiment, three levels of copper pollution were used: 200, 400, and 600 mg Cu kg−1, against a control without Cu. The soil was amended with three types of OAs: pine bark (PB), peat moss (PM), and cattle manure (CM). Our research showed that plant condition depends on the Cu content in the soil. Increasing soil contamination significantly affected the plant yield, leaf greenness index, and dry matter content. The type of OA had no significant effect on the condition of black mustard (BM); however, each had a different effect on neutralizing the harmful effects of Cu. CM reduced Cu accumulation, PM showed no effect, while PB contributed to a significant increase in Cu content in BM plants. The chemical composition of BM depended on the Cu content in the soil. With increased soil contamination with Cu, the contents of Ntot, K, Mg, Ca, and Na in BM increased, while the content of P decreased. In terms of mitigating the harmful effects, CM was more beneficial than PM and PB. Among the analyzed OAs, CM, and PM contributed to Cu immobilization, while PB promoted Cu mobilization in contaminated soils. [ABSTRACT FROM AUTHOR]

Bulk density (Db) and subsequent physical properties are determined by the substrate and packing method. Packing method is the way one fills and compresses a substrate within a given volume. Bulk density produced in the laboratory may not align with “expected” published ranges due to variations in packing. Additionally, it is unknown if ranges identified as “typical” using a small volume sample ring reflect Db occurring in larger production size containers packed using commercial potting practices. Therefore, our objectives were to 1) emulate nursery practices and document the Db associated with a potted 2.8-L (#1) container, 2) develop and test the new “shim and compression” method to determine if it consistently packs sample rings to a Db commensurate with that of a 2.8-L nursery container, and 3) demonstrate how static physical properties are affected by the new “shim and compression” sample ring packing method compared with the traditional bench top tap method. When emulating nursery potting practices with 100% pine bark, coir, and peat, and blends of each, Db ranged from 0.08 g⋅cm−3 (coconut coir) to 0.17 g⋅cm−3 (pine bark). We used an espresso tamp and shims to pack the aforementioned substrates in sample rings. The Db achieved using a range in number of presses and discs was largely dependent on the substrate, but the desired Db was consistently achieved for each substrate. There was no effect of disc number on Db (P = 1.000) for any substrate. There was no effect of tamp number (P ≥ 0.0602) for all substrates except peat-amended, for which five tamps yielded a greater Db than one tamp (P = 0.0324). In an experiment in which a different technician who was accustomed to the conventional benchtop tap packing method performed both methods, method influenced Db (P < 0.0001), and the conventional method more closely attained the target Db. To our knowledge, this is the only report of Db observed in commercial container production facilities (i.e., “native”).

Rhizosphere pH determines nutrient bioavailability, but this pH is difficult to measure. Standard pH tests require adding water to growth media. This dilutes hydrogen ion activity and increases pH. We used a novel, in situ, pointed-tip electrode to estimate rhizosphere pH without dilution. Measurements from this electrode matched a research-grade pH meter in hydroponic nutrient solutions. We then compared measurements from this electrode to saturated paste and pour-through methods in peat moss, coconut coir, and pine bark. The pointedtip electrode was unable to accurately measure pH in the highly-porous pine bark media. Adding deionized water to the other media at container capacity using the saturated paste method resulted in a pH that was 0.59 ± 0.30 units higher than the initial in situ measurement at the top of the container. This increase aligns with established solution chemistry principles. Measurements of pH using the pour-through method were 0.38 ± 0.24 pH units higher than in situ measurements at the bottom of the container. We conclude that in situ pH measurements are not subject to dilution and are thus more representative of the rhizosphere pH than the saturated paste and pour-through techniques. [ABSTRACT FROM AUTHOR]

Phosphorus (P) fertilizers applied to container-grown nursery crops readily leach through pine bark-based substrates and can subsequently runoff and contribute to surface water contamination. The objectives of this research were to determine the effect of adding a layer of FeSO4·7H2O-amended pine bark (FSB) to the bottoms of nursery containers on P leaching characteristics. Phosphorus and iron (Fe) leaching in response to FSB layer height (4 or 7.5 cm), FeSO4·7H2O rate (0.3, 0.6, or 1.2 kg·m−3 Fe), and form (i.e., granular versus liquid) used to formulate the FSB layer, and the inclusion of dolomite in the FSB layer were also investigated. Greenhouse studies lasting 15 and 19 weeks were conducted, in which 2.5 L nursery containers containing the FSB layer treatments below non-amended pine bark substrate were fertilized with 199 or 117 mg P from a soluble or controlled-release fertilizer, respectively. Leachate resulting from daily irrigation was collected and analyzed for P and Fe weekly. All FSB treatments leached less P than the control (non-amended pine bark only), with P reductions ranging from 22% (4 cm FSB with 0.3 kg·m−3 Fe) to 73% (7.5 cm FSB with 1.2 kg·m−3 Fe). Phosphorus leaching decreased linearly with an increase in Fe rate or layer height. The amount of Fe that leached from containers with FSB was <5% of that applied, regardless of the Fe rate. Granular- and liquid-applied FeSO4·7H2O with or without dolomite were equally effective at reducing P leaching. Adding 0.6 kg·m−3 Fe to the bottom 500 cm3 of pine bark increased P adsorption by 0.053 mg·cm−3 P, which equates to 17.9 mg P adsorbed per gram of FeSO4·7H2O added. Results from this research suggest that including an FSB layer in the bottom of nursery containers is an effective strategy for reducing P runoff from container-based nursery production sites. [ABSTRACT FROM AUTHOR]

Tamarind (Tamarindus indica L.) is a species with promising potential for commercial production; therefore, studies involving practices of conducting culture in the initial stage are essential. The present study aimed to evaluate different shading levels and substrate compositions in the seedling production of tamarind. The experimental design was completely randomized in a 4×4 factorial scheme, four levels of shading (0%, 18%, 30%, and 50%) and four substrates (pine bark-based substrate pure and mixed with 50% vermiculite, and sphagnum peat-based substrate pure and mixed with 50% vermiculite), with four replicates of four seedlings. Growth and biometric relationships were evaluated at 40 and 98 d after transplantation (DAT). The results reported that seedlings formed on the sphagnum peat-based substrate on pure or associated with vermiculite at 98 DAT had a height greater than 35 cm and a total 8.5 g DM. In contrast, seedlings produced in pine bark-based substrate did not reach 20 cm in height and had less than 3 g total DM. The condition of 30% and 50% shading promoted greater growth in height, reaching an average height greater than 40 cm, while in the full sun environment, seedlings showed an average of less than 35 cm; however, for the other variables, full sun environment did not differ from 30% shading, producing good quality seedlings. Thus, the cultivation of seedlings in an environment with 0% or 30% shading, associated with the sphagnum peat-based substrate pure or mixed with 50% vermiculite promoted the production of tamarind seedlings with vigorous growth. In the best environments, the best substrates increased, on average, 41.3% number of leaves, 80.5% shoot dry mass, 56.8% root dry mass, and 71.0% total dry mass. In the best substrates, the best environments increased, on average, 18.0% number of leaves, 20.7% shoot dry mass, 8.7% root dry mass, and 14.3% total dry mass. [ABSTRACT FROM AUTHOR]

Greenhouse tomato production faces multiple challenges, including the excessive use of nonrenewable substrates that are difficult to dispose of after use. Currently, most growers propagate tomatoes in rockwool, but there is an increasing demand for sustainable media. The objective of this research was to evaluate sustainable and organic alternatives for greenhouse propagation of tomato seedlings intended for high-wire production. Different organic and inorganic substrates were evaluated in three experiments, using a nutrient solution composed of a complete water-soluble fertilizer. Germination and growth parameters, including height, stem diameter, number of leaves, leaf area, foliar chlorophyll levels (SPAD), and shoot fresh and dry weight, were measured. In the first experiment, which employed overhead irrigation, rockwool, coir, wood fiber–coir mix, medium-grade pine bark, pine bark < 0.64 cm, and pine bark < 0.32 cm were evaluated. Tomato germination was faster and achieved higher percentages with pine bark < 0.64 cm compared to other substrates. However, growth performance was similar or better in coir than in rockwool four weeks after transplantation. For the second experiment with sub-irrigation only, rockwool, coir, wood fiber–coir mix, pine bark < 0.32 cm bark, and peat were evaluated at different container heights. Peat resulted in greater growth across all parameters, followed by wood fiber–coir mix in all container heights, while pine bark had the least growth across all measured parameters. In the third experiment with overhead irrigation, rockwool, wood fiber–coir mix, pine bark < 0.32 cm, and a commercial peat-based mixture were evaluated under different fertilizer rates (electrical conductivity of 1.1 and 2.2 mS·cm−1). Wood fiber–coir mix, peat-based mix, and rockwool were the substrates with the highest values for all evaluated parameters. While all the organic substrates showed potential for use in tomato propagation, pine bark < 0.32 cm bark and wood fiber–coir mix provided the best media for germination. Peat and wood fiber–coir mix showed the best media for subsequent seedling growth and demonstrated potential to be used as substitutes for rockwool. [ABSTRACT FROM AUTHOR]

The work provides a comprehensive assessment of changes in the intensity of pollution of soils and plants of pine forests with increasing distance from the main sources of pollution. Within the forest-steppe zone of the Chelyabinsk region, zones of environmental tension have been identified based on the summary index of soil contamination with mobile forms of chemical elements and on the level of pine bark contamination. The main polluting elements were Cr, Pb, Zn, Cd, the content of which in soils was tens of times higher than the background values. The same pollutants and Cu were noted for pine bark, but their concentrations were significantly lower and exceeded the background only several times. High values of correlation coefficients between pollution indicators for soils and bark were noted for Pb, Cu, Zn and the summary indices of contamination. The content of most of the studied chemical elements in pine needles does not exceed background values, but the Al and Ni content in some plots near industrial enterprises can be 2–4 times higher than background values. [ABSTRACT FROM AUTHOR]

Due to the widespread use of the pour-through extraction procedure in horticultural production and research, the objective of this study was to determine if the method is biased by preferentially extracting substrate solution near the bottom of the container in both conventionally filled containers as well as intentionally stratified containers. Eight treatments were created using 2.5-L, 17.5-cm tall plastic nursery containers. The first four treatments were created by layering a conventional pine bark substrate (CONV) that was either amended (+A) or nonamended (2A) with fertilizer and lime with the following layers: amended substrate throughout the entire container profile (+A/+A); amended substrate in the top half (top 8.5 cm) over nonamended substrate in the bottom half of the container profile (+A/2A); nonamended substrate in the top half over amended substrate in the bottom half (2A/+A); and nonamended substrate throughout the profile (2A/2A). An additional four treatments were created by intentionally stratifying (STRAT) a fine pine bark substrate (FINE) over a coarse pine bark substrate (CRSE) with the same amendment combinations of +A or 2A. On 0 and 42 d after potting, substrate pH and electrical conductivity (EC) were determined on samples collected by the pour-through procedure and 1:1 water extracts of the top and bottom layers in the container. At 42 d after potting, nutrient ions (NO3 2, PO4 22, K, Ca, Mg, and SO4 22) were also measured in both pour-through and 1:1 water extracts of the top and bottom layers. At both dates and in both CONV and STRAT containers, pourthrough substrate pH and EC more closely reflected those measurements in the bottom half of the container as determined by the 1:1 water extract. At 42 d after potting, nutrient ions determined by the pour-through procedure were more highly correlated to the 1:1 water extracts from the bottom half of the container compared with the top half of the container in both CONV and STRAT substrates. Evidence herein demonstrates that the pour-through procedure is more reflective of the lower half of the container than the upper half for both CONV and stratified substrates. [ABSTRACT FROM AUTHOR]

Rhizosphere pH determines nutrient bioavailability, but this pH is difficult to measure. Standard pH tests require adding water to growth media. This dilutes hydrogen ion activity and increases pH. We used a novel, in situ, pointed-tip electrode to estimate rhizosphere pH without dilution. Measurements from this electrode matched a research-grade pH meter in hydroponic nutrient solutions. We then compared measurements from this electrode to saturated paste and pour-through methods in peat moss, coconut coir, and pine bark. The pointed-tip electrode was unable to accurately measure pH in the highly-porous pine bark media. Adding deionized water to the other media at container capacity using the saturated paste method resulted in a pH that was 0.59 ± 0.30 units higher than the initial in situ measurement at the top of the container. This increase aligns with established solution chemistry principles. Measurements of pH using the pour-through method were 0.38 ± 0.24 pH units higher than in situ measurements at the bottom of the container. We conclude that in situ pH measurements are not subject to dilution and are thus more representative of the rhizosphere pH than the saturated paste and pour-through techniques.

In recent years, there are many concerns about the potential risks of contamination of emerging compounds in water resources and their adverse effects on human health and the environment. Today, the production and use of drug compounds for the treatment of human and animal diseases is increasing. The aim of this study was to investigate the effect of the biosorbent prepared from pine bark on the removal of tetracycline from aqueous solutions. In this study, the effect of various variables including pH (2–12), adsorbent dose (1–2 g)), tetracycline concentration (50–500 mg/L), contact time (10–120 min)) and temperature (10–50°C) as well as the structural properties of biochar were examined. The isotherms, kinetics and thermodynamics of the adsorption process were also evaluated. The residual concentration of tetracycline after adsorption by DR5000 spectrophotometer of the Hack Company at 292 wavelengths was read. Using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) methods, it was found that the biochar structure has many pores for adsorption and also has functional groups including hydroxyl, carbonyl and amine, which increases the adsorption capacity. Maximum removal of tetracycline (89.5%) was achieved in 15 minutes, pH 5.1 and dose 1 g. In this study, the removal efficiency of tetracycline increased with increasing temperature and adsorbent dose and decreased with increasing contaminant concentration. The adsorption isotherm of tetracycline at maximum adsorption capacity (58.47 mg/g) is consistent with the Langmuir model and the adsorption kinetics follows the pseudo- second order model. According to the results of this study, it was found that biochar produced from pine bark is a cheap and efficient adsorbent in the removal of tetracycline antibiotic and can be used to remove this antibiotic in hospital wastewaters. [ABSTRACT FROM AUTHOR]

The substrate is one of the main inputs for the production of Yerba Mate (YM) seedlings (Ilex paraguariensis A. St.-Hil.) and its properties must be adequate according to the cultivation system. The objective of this work was to analyze physical properties of substrates made with pine bark compost (CCP) and Sphagnum peat (T) and to evaluate their effects on the morphological quality of YM seedlings produced in alveolar plastic trays. The trial consisted of five treatments: 100% T; 75% T + 25% CCP; 50% T + 50% CCP; 25% T + 75% CCP and 100% CCP. The following variables were analyzed for each substrate: pH, electrical conductivity (EC), bulk density (Dap), total pore space (EPT), water retention capacity (CRA), aeration porosity (PA) and granulometry. Stem length and diameter, aerial dry mass (MSA) and root dry mass (MSR) were measured on 45 seedlings per treatment and the robustness index (IR) and Dickson quality index (ICD) were calculated. The statistical analyses used were principal component analysis, analysis of variance and Tukey's test (P < 0.05). All the substrates had pH and EC values within an adequate range (5.5 to 6.8 and < 1 dS m-1). The CRA increased and the PA decreased in response to increasing amounts of T, with significant differences among treatments (P < 0.0001). Seedlings grown under 75% T + 25% CCP, 50% T + 50% CCP and 25% T + 75% CCP had higher MSA while those under 100% T had lower MSR. The lowest IR was identified in seedlings under 25% T + 75% CCP and 100% CCP. The seedlings under 75% T + 25% CCP, 50% T + 50% CCP and 25% T + 75% CCP showed higher ICD. In conclusion, YM seedlings with the highest quality and robustness were obtained in substrates with EPT > 85%, CRA = 55%, PA = 35% and Dap = 200 kg m-3. [ABSTRACT FROM AUTHOR]

This study established a full-scale hybrid water treatment system combining a hydrocyclone, coagulation, flocculation, and dissolved air flotation unit (HCFD) and evaluated its performance in treating anthropogenically impacted lake water. The HCFD system offered the stable and efficient treatment of fluctuating influent loadings, meeting most of the highest water reclamation quality criteria except for that of organic matter. Adsorption was subsequently examined as a post-treatment process for the HCFD effluent, which has not been examined in many previous studies. As the adsorbent for the post-treatment, pine bark, a locally available agricultural waste feedstock, was modified using H2O2 to maximize its adsorption capacity. The surface modification increased its adsorption capacity for organic matter by 53–112%. The HCFD system in conjunction with the synthesized adsorbent thus demonstrated the ability to meet the highest standards for all water quality parameters, highlighting their synergistic potential for enhancement of water treatment. Liquid chromatography–organic carbon detection and Fourier transform infrared analysis were then employed to determine the mechanisms involved in the removal of specific contaminants using the HCFD system and post-adsorption unit. While the HCFD system successfully eliminated particulate and colloidal matter (e.g., phosphorous and biopolymers with a high molecular weight) using centrifugal and floating separation with the aid of two complementary polymers, the post-adsorption unit effectively adsorbed small-sized dissolved substances (e.g., low molecular weight acids and building blocks) via surface functional groups (–CH, –OH, –CH2, C=O, C=C, and C=O) using van der Waals forces, hydrogen bonding, and π–π or n–π interactions. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the influence of organic amendments (OAs) on neutralizing the harmful effect of copper (Cu) on black mustard (Sinapis nigra L.). In a pot experiment, three levels of copper pollution were used: 200, 400, and 600 mg Cu kg−1, against a control without Cu. The soil was amended with three types of OAs: pine bark (PB), peat moss (PM), and cattle manure (CM). Our research showed that plant condition depends on the Cu content in the soil. Increasing soil contamination significantly affected the plant yield, leaf greenness index, and dry matter content. The type of OA had no significant effect on the condition of black mustard (BM); however, each had a different effect on neutralizing the harmful effects of Cu. CM reduced Cu accumulation, PM showed no effect, while PB contributed to a significant increase in Cu content in BM plants. The chemical composition of BM depended on the Cu content in the soil. With increased soil contamination with Cu, the contents of Ntot, K, Mg, Ca, and Na in BM increased, while the content of P decreased. In terms of mitigating the harmful effects, CM was more beneficial than PM and PB. Among the analyzed OAs, CM, and PM contributed to Cu immobilization, while PB promoted Cu mobilization in contaminated soils.

Due to the widespread use of the pour-through extraction procedure in horticultural production and research, the objective of this study was to determine if the method is biased by preferentially extracting substrate solution near the bottom of the container in both conventionally filled containers as well as intentionally stratified containers. Eight treatments were created using 2.5-L, 17.5-cm tall plastic nursery containers. The first four treatments were created by layering a conventional pine bark substrate (CONV) that was either amended (+A) or nonamended (−A) with fertilizer and lime with the following layers: amended substrate throughout the entire container profile (+A/+A); amended substrate in the top half (top 8.5 cm) over nonamended substrate in the bottom half of the container profile (+A/−A); nonamended substrate in the top half over amended substrate in the bottom half (−A/+A); and nonamended substrate throughout the profile (−A/−A). An additional four treatments were created by intentionally stratifying (STRAT) a fine pine bark substrate (FINE) over a coarse pine bark substrate (CRSE) with the same amendment combinations of +A or −A. On 0 and 42 d after potting, substrate pH and electrical conductivity (EC) were determined on samples collected by the pour-through procedure and 1:1 water extracts of the top and bottom layers in the container. At 42 d after potting, nutrient ions (NO3−, PO42−, K, Ca, Mg, and SO42−) were also measured in both pour-through and 1:1 water extracts of the top and bottom layers. At both dates and in both CONV and STRAT containers, pour-through substrate pH and EC more closely reflected those measurements in the bottom half of the container as determined by the 1:1 water extract. At 42 d after potting, nutrient ions determined by the pour-through procedure were more highly correlated to the 1:1 water extracts from the bottom half of the container compared with the top half of the container in both CONV and STRAT substrates. Evidence herein demonstrates that the pour-through procedure is more reflective of the lower half of the container than the upper half for both CONV and stratified substrates.

The focus of the research was to evaluate the use of lignin from different sources as an agent for the removal of diverse types of microplastics when present in wastewater. Organosolv lignin was obtained from three different sources (Miscanthus sp., pine bark and solid anaerobic digestates from Organic Fraction of Municipal Solid Wastes) by an ethanol-based organosolv treatment carried out in a pressurized stirred-tank reactor. The lignins obtained were evaluated as an adsorbent for diverse types of microplastics: High-density polyethylene (HDPE), Polystyrene (PS), Expanded Polystyrene (EPS), and Polypropylene (PP). All lignins used had the capacity to capture plastic particles from all plastic types, but a differential absorbance potential was found both for plastic types and lignin samples. EPS was the least adsorb type for all lignin sources, with the remaining plastics presenting equivalent results. Pine bark lignin was the best adsorbent among the tested feedstocks, always presenting the best performance for all plastic types. The direct utilization of organosolv hydrolysates, avoiding lignin recovery presented a similar behaviour. These results open the possibility to develop new natural, plant-based, adsorbents for microplastic removal from contaminated wastewater. [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) is one of the most toxic heavy metals found in industrial wastewater, so many researchers are working to develop efficient and environmentally friendly removal methods. It has been reported that natural biomass and its derivatives can be used to treat wastewaters containing Cr(VI). However, biomass with sufficient Cr(VI) removal performance to replace the existing chemical method, which is cheap and simple, has not been reported yet. This study reports that inexpensive, abundant, and commercially available pine bark has the highest Cr(VI) removal capacity (i.e., 376.3 mg/g) compared to biomass reported elsewhere. This value is six times higher than the theoretical value of an inorganic reducing agent (iron(II) sulfate heptahydrate). The main mechanism of Cr(VI) removal by pine bark was clearly identified through kinetic experiments, Fourier-transform infrared spectrometer, and X-ray photoelectron spectroscopy analyses, which were used to study the compositions, functional groups, and bonding states of pine bark. It was found that pine bark consists of various acidic functional groups that can act as electron donors to promote the removal of Cr(VI) through redox reactions. In conclusion, pine bark may be a promising candidate for the removal of Cr(VI) from wastewater, owing to its excellent removal capacity. [ABSTRACT FROM AUTHOR]

The ability of a substrate component (organic or inorganic) to capture and retain water (hydration and wettability) is important to investigate and promote water-use–efficient practices. Many factors may play a role in the wettability of the material, including the processing of the material and its initial handling. The goal of this experiment was to determine the effect of moisture content (MC) on the sorptive behavior of substrates after an initial and secondary hydration cycle. Coir, peat, and aged pine bark were evaluated at a 33%, 50%, and 66% MC by weight. At all moisture levels, coir and bark were minimally affected by MC or the initial hydration cycle. Peat was the most vulnerable to changes in sorptive behavior as a result of wetting and drying cycles. After a wetting and drying cycle, the maximum volumetric water content of peat from surface irrigation was reduced 21.5% (volumetrically), more than three times any other treatment. The hydration efficiency of peat was improved when blended with as little as 15% coir. These experiments provide evidence that MC and initial handling of the substrate can lead to differences in initial water use efficiency.

Phosphorus (P) fertilizers applied to container-grown nursery crops readily leach through pine bark-based substrates and can subsequently runoff and contribute to surface water contamination. The objectives of this research were to determine the effect of adding a layer of FeSO4·7H2O-amended pine bark (FSB) to the bottoms of nursery containers on P leaching characteristics. Phosphorus and iron (Fe) leaching in response to FSB layer height (4 or 7.5 cm), FeSO4·7H2O rate (0.3, 0.6, or 1.2 kg·m−3 Fe), and form (i.e., granular versus liquid) used to formulate the FSB layer, and the inclusion of dolomite in the FSB layer were also investigated. Greenhouse studies lasting 15 and 19 weeks were conducted, in which 2.5 L nursery containers containing the FSB layer treatments below non-amended pine bark substrate were fertilized with 199 or 117 mg P from a soluble or controlled-release fertilizer, respectively. Leachate resulting from daily irrigation was collected and analyzed for P and Fe weekly. All FSB treatments leached less P than the control (non-amended pine bark only), with P reductions ranging from 22% (4 cm FSB with 0.3 kg·m−3 Fe) to 73% (7.5 cm FSB with 1.2 kg·m−3 Fe). Phosphorus leaching decreased linearly with an increase in Fe rate or layer height. The amount of Fe that leached from containers with FSB was 4·7H2O with or without dolomite were equally effective at reducing P leaching. Adding 0.6 kg·m−3 Fe to the bottom 500 cm3 of pine bark increased P adsorption by 0.053 mg·cm−3 P, which equates to 17.9 mg P adsorbed per gram of FeSO4·7H2O added. Results from this research suggest that including an FSB layer in the bottom of nursery containers is an effective strategy for reducing P runoff from container-based nursery production sites.

Greenhouse tomato production faces multiple challenges, including the excessive use of nonrenewable substrates that are difficult to dispose of after use. Currently, most growers propagate tomatoes in rockwool, but there is an increasing demand for sustainable media. The objective of this research was to evaluate sustainable and organic alternatives for greenhouse propagation of tomato seedlings intended for high-wire production. Different organic and inorganic substrates were evaluated in three experiments, using a nutrient solution composed of a complete water-soluble fertilizer. Germination and growth parameters, including height, stem diameter, number of leaves, leaf area, foliar chlorophyll levels (SPAD), and shoot fresh and dry weight, were measured. In the first experiment, which employed overhead irrigation, rockwool, coir, wood fiber–coir mix, medium-grade pine bark, pine bark < 0.64 cm, and pine bark < 0.32 cm were evaluated. Tomato germination was faster and achieved higher percentages with pine bark < 0.64 cm compared to other substrates. However, growth performance was similar or better in coir than in rockwool four weeks after transplantation. For the second experiment with sub-irrigation only, rockwool, coir, wood fiber–coir mix, pine bark < 0.32 cm bark, and peat were evaluated at different container heights. Peat resulted in greater growth across all parameters, followed by wood fiber–coir mix in all container heights, while pine bark had the least growth across all measured parameters. In the third experiment with overhead irrigation, rockwool, wood fiber–coir mix, pine bark < 0.32 cm, and a commercial peat-based mixture were evaluated under different fertilizer rates (electrical conductivity of 1.1 and 2.2 mS·cm−1). Wood fiber–coir mix, peat-based mix, and rockwool were the substrates with the highest values for all evaluated parameters. While all the organic substrates showed potential for use in tomato propagation, pine bark < 0.32 cm bark and wood fiber–coir mix provided the best media for germination. Peat and wood fiber–coir mix showed the best media for subsequent seedling growth and demonstrated potential to be used as substitutes for rockwool.

The effectiveness of inorganic (plastic) and organic (geotextile and pine bark) mulching materials for soil salinity control as compared to the bare soil was assessed during three years in a semi-arid, drip-irrigated nectarine orchard. The soil solution electrical conductivity (ECss) was measured in 3174 samples regularly extracted with suction cups at two soil depths (20 and 40 cm) and three sampling positions (EM-emitter, EL-emitter line, and TR-tree row) during the 2010–2012 irrigation seasons. Considering all treatments, ECss increased (p <.05) with distance to emitters, both vertically (mean ECss = 4.7 dS m−1 at 20 cm and 6.3 dS m−1 at 40 cm soil depths) and horizontally (mean ECss (20 + 40 cm soil depth) = 2.9 dS m−1 at EM, 4.4 dS m−1 at EL, and 9.1 dS m−1 at TR). The monthly changes in ECss were negatively correlated (p <.01) with the monthly field-wide leaching fraction estimates. Based on the 2010–2012 mean ECss values, the effectiveness for soil salinity control of the examined treatments was (p =.05): plastic (4.2 dS m−1) = pine bark (4.6 dS m−1) < bare soil (5.8 dS m−1) = geotextile (5.9 dS m−1). Overall, due to their lower soil water evaporation rates, the plastic and pine bark materials were best suited for soil salinity control under the prevailing climatic characteristics in the study area. [ABSTRACT FROM AUTHOR]

The tree bark and cones are either burned or left in the forest. In both cases, it causes both environmental problems and a significant loss of economic potential. In this study, some physical and mechanical properties of molded thermal insulation materials produced from natural raw materials were investigated experimentally. In this context, 15 types of sandwich panel materials containing honeycomb-shaped core were produced from pine (Pinus brutia Ten.) bark and cones. The mean moisture content, density, compressive strength, tensile strength perpendicular to the surface, tensile strength parallel to the surface, and dimensional stability values of the materials were 10.6%, 269.717 kg/m3, 0.493.06 N/mm2, 0.011 N/mm2, 0.150 N/mm2 and −0.156%, −0.054%, 0.942%, respectively. According to the results, it was determined that the increase in particle size and perlite ratio in the materials produced from the bark decreased the density. Moreover, it was found that the particle size-moisture content relationship and the perlite ratio-moisture content relationship varied in the materials containing bark and cones, that the mechanical properties were higher in the materials containing cones, and that the dimensional stability did not show a regular change. [ABSTRACT FROM AUTHOR]

Pine bark, a natural and renewable forest residue, was modified using a simple interfacial solid-phase chemical method to design a highly chemically reactive additive for urea-formaldehyde (UF) resin. The modification introduced carbonyl groups onto the bark surface during the glyoxal reaction at the bark-solid interface. Thermal properties, including curing temperatures, of UF, UFB, and UFGB were evaluated using DSC and DMA. Glyoxal modification of bark significantly influenced these properties, facilitating the crosslinking and curing of adhesives. Notably, plywood bonded with UFGB resin released approximately half as much formaldehyde (52.89 % less) compared to plywood bonded with UF resin, reducing from 1.38 to 0.65 mg/L. Additionally, the wet shear strength of plywood increased by 197.3 %, from 0.37 MPa to 1.10 MPa, exceeding the minimum requirement (0.7 MPa) defined by the China national standard (GB/T 17657–2013). The study presents a compelling case for the utilization of glyoxal-modified pine bark as a filler in UF adhesive for plywood manufacturing. The demonstrated improvements in plywood properties and formaldehyde emissions, along with the environmentally friendly nature of the approach, make it a promising avenue for sustainable plywood production. Further investigations into the underlying mechanisms and long-term performance are encouraged to solidify the potential of this technology. [Display omitted] • Reduced formaldehyde emissions: Plywood bonded with a UF resin containing glyoxal-modified pine bark as a reactive additive released nearly 53 % less formaldehyde , a major health concern. • Enhanced strength: The wet shear strength of the plywood increased by almost 200 % , exceeding national standards. • Sustainable approach: Utilizing a natural waste product and a simple modification process makes this method environmentally friendly. • Cost-effective: The modified bark powder can be easily incorporated into existing production lines, minimizing additional costs. [ABSTRACT FROM AUTHOR]

• Blending of sesame straw with sugarcane pressmud and pine bark produced best quality plants. • Tested substrate had optimal physico-chemical and growth attributes of geranium and marva. • Both species did not perform well when grown in sesame straw, date palm coir & sugar beet waste. • Substrate shrinkage in containers was highest with sesame straw, sugarcane pressmud and pine bark. • Tested indigenous substrate can be used as alternative of peat moss and coco coir. Due to their hiking prices and import restrictions, peat moss and coco coir are not readily available in many developing countries including Pakistan. Therefore, it is necessary to explore alternative soilless substrates having low cost and comparable physico-chemical properties with peat moss and coco coir for local and global market. For this purpose, indigenous agro-industrial by-products, viz., sesame straw, date palm coir, sugarcane pressmud, sugar beet waste and pine bark were collected, cleaned, crushed (where needed) and blended for physico-chemical analyses. Zonal geranium 'Pinto White' and murva (Murraya paniculata Kaneh.) were used to evaluate the efficacy of various combinations of substrates on plant growth and production. Three experiments were conducted with six treatments of each experiment replicated three times. Blending of sesame straw with sugarcane pressmud and pine bark (4:4:2 by volume) yielded best results and marketable plants were produced with tallest height (35.8 cm), canopy diameter (20.8 cm), leaf area (29.2 cm2), leaf total chlorophyll contents (62.1 SPAD) and flowers per plant (5.0 No.) along with shortest production time (103 days). Same results were recorded when murva plants were grown in 4:4:2 blending of sesame straw, sugarcane pressmud and pine bark. Zonal geranium and murva plants did not perform well when sesame straw was blended with date palm coir and sugar beet waste. Blending of sesame straw with sugarcane pressmud and pine bark had low pH (7.0), electrical conductivity (1.37 mS cm-1), bulk density (0.29 g cm-3) while high water retention (34.7 %) as compared to other blended substrates. However, shrinkage of substrates in containers was highest (7.7 %) when sesame straw was blended with sugarcane pressmud and pine bark in 5:3:2 followed by 4:4:2. pH value of all blended substrates decreased at termination except when sesame straw, sugarcane pressmud and pine bark were blended in 4:4:2 and 5:2:3, which was increased from 7.0 to 7.1. Electrical conductivity of all blended substrates was decreased at termination of the experiments. It can be concluded that blending of sesame straw, sugarcane pressmud and pine bark in 4:4:2 (v/v/v) significantly improved physico-chemical characteristics of substrates as well as plant growth and production attributes of zonal geranium and murva. Therefore, this indigenous soilless substrate, which is cheaper and readily available to nurserymen can be used as alternative of peat moss and coco coir for containerized plant production. [ABSTRACT FROM AUTHOR]

Growers rely on soilless substrates to provide sufficient water and nutrients to containerized crops. Traditional bark-based substrates are engineered to have relatively low water-holding capabilities, which can lead to nonuniform rewetting patterns and inefficient usage of water resources. Engineering substrates to redistribute water dynamics and maximize aeration within the container may improve water resource efficiencies. The goal of this study was to evaluate whether more efficient irrigation schedules can be used when stratifying unique substrates within a container for added crop water and nutrient efficiency. Loropetalum chinense ‘Ruby’ liners were planted and grown in a conventional pine bark substrate or one of three stratified substrate treatments, including a bark:peat, bark:coir, or fine bark layered on top of a coarse bark. The crops were grown under four different irrigation schedules, including single daily application, single application at deficit levels, cyclic application, or cyclic at deficit schedules. Stratified substrates improved crop growth, quality, and yield when compared with plants grown in conventional bark in the single application irrigation treatment. Measured at final harvest, substrates positively influenced plant growth index (P < 0.0001), whereas irrigation scheduling alone had no effect (P = 0.6321). There was a strong interaction between substrate and irrigation schedules on Δ growth index (P = 0.0141). There were strong substrate effects on shoot dry weight (P = 0.0060), root dry weight (P = 0.0342), and growth index (P = 0.0040). The stratified bark:coir treatment outgrew all other substrate treatments. In addition, within all irrigation treatments, plants grown with the stratified bark:coir substrate had the highest survival ratings among the other substrate treatments, whereas the conventional bark had the lowest survival rates. Substrate and irrigation had an effect on nitrogen and potassium leachate concentrations levels (P = 0.0107 and P = 0.0004, respectively). Evaluation of microbial communities showed that substrate (P = 0.0010) and the stratified layer (P = 0.0010) had strong influences on the type of community present and the relative abundance in the treatments used herein this study. Specifically, within cyclic scheduling, bark:peat actinomycete populations were significantly greater than other substrate treatments. Furthermore, under deficit irrigation, stratified substrate systems were able to mitigate crop water stress. The results indicate that when crops such as the Loropetalum are grown in the stratified system, crop growth can be sustained when drought conditions are present. This is possible by providing adequate water availability even under low water inputs until subsequent irrigations during the fragile establishment period, when compared with using traditional bark-based substrates.

The ability of a substrate component (organic or inorganic) to capture and retain water (hydration and wettability) is important to investigate and promote water-use– efficient practices. Many factors may play a role in the wettability of the material, including the processing of the material and its initial handling. The goal of this experiment was to determine the effect of moisture content (MC) on the sorptive behavior of substrates after an initial and secondary hydration cycle. Coir, peat, and aged pine bark were evaluated at a 33%, 50%, and 66% MC by weight. At all moisture levels, coir and bark were minimally affected by MC or the initial hydration cycle. Peat was the most vulnerable to changes in sorptive behavior as a result of wetting and drying cycles. After a wetting and drying cycle, the maximum volumetric water content of peat from surface irrigation was reduced 21.5% (volumetrically), more than three times any other treatment. The hydration efficiency of peat was improved when blended with as little as 15% coir. These experiments provide evidence that MC and initial handling of the substrate can lead to differences in initial water use efficiency. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is the most common type of dementia with cognitive impairment. Various plant-derived phenolics are known to alleviate cognitive impairment in Alzheimer's disease by radical scavenging and strengthening synaptic plasticity activities. Here, we examined the cognition-improving effect of Pinus densiflora Sieb. et Zucc. bark extract (PBE). We identified and quantified phenolics in the PBE using a UHPLC-Orbitrap mass spectrometer. To evaluate the cognition-enhancing effects of PBE, scopolamine-induced amnesic Sprague-Dawley (SD) rats (5 weeks old) and ion channel antagonist-induced organotypic hippocampal slices of SD rats (7 days old) were used. Twenty-three phenolics were tentatively identified in PBE, 10 of which were quantified. Oral administration of PBE to the scopolamine-induced SD rats improved cognitive impairment in behavioral tests. PBE-fed SD rats showed significantly improved antioxidant indices (superoxide dismutase and catalase activities, and malondialdehyde content) and reduced acetylcholinesterase activity in hippocampal lysate compared with the scopolamine group. PBE increased the long-term potentiation (LTP) induction and rescued LTP from blockades by the muscarinic cholinergic receptor antagonist (scopolamine) and N-methyl-D-aspartate channel antagonist (2-amino-5-phosphonovaleric acid) in the organotypic hippocampal slices. These results suggest that polyphenol-rich PBE is applicable as a cognition-improving agent due to its antioxidant properties and enhancement of LTP induction. [ABSTRACT FROM AUTHOR]

The heterogeneity of horticultural substrates makes basic physical characteristics, such as total porosity and particle density, difficult to estimate. Due to the material source, inclusion of occluded pores, and hydrophobicity, particle density values reported from using liquid pyknometry, vary widely. Gas pycnometry was used to determine the particle density of coir, peat, perlite, pine bark, and wood substrates. Further precision was examined by gas species and separation by particle size. The calculated particle densities for each material determined by He, N2, and air were relatively constant and varied little despite the species of gas used. Particle size affected the measured particle density of perlite and pine bark but was minimal with coir, peat, and wood. Reducing the particle size removed more occluded pores and the measured particle density increased. Given the small variability, the use of particle density values obtained by gas pycnometry provides repeatable, precise measurements of substrate material total porosity.

The paper presents a novel pine bark based biosorbent for solid-phase extraction (SPE). The morphology and composition of the pine bark were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The biosorbent was used for the preparation of wastewater for the determination of phenylbutazone, sulfamethazine, carbendazim, and linuron by high performance liquid chromatography with ultraviolet detection (HPLC-UV). The SPE conditions were optimized with respect to elution solvent, sample volume, and extraction pH. The results showed that developed sorbent provides good repeatability. The relative standard deviation (n = 3), was between 0.3 and 2.2%. The limits of detection (LOD) were between 0.11 and 0.4 µg.L−1. The developed method was used for determination of the analytes in effluent from a wastewater treatment plant. [ABSTRACT FROM AUTHOR]

Soilless substrate stratification (i.e., layering unique substrates within a single container) is an emerging substrate management strategy that may provide opportunities to augment nursery resource use. As such, this research aimed to analyze water movement through containers during hydration events under different initial moisture conditions. The results indicated substrate stratification had minimal influence on water movement compared to non-stratified systems (uniformly filled nursery containers). Cyclic irrigation significantly increased the stratified substrates' ability to retain water when irrigated at 20% volumetric water content (p < 0.0001) and significantly decreased the total volume leached (p < 0.0001). Moreover, irrigating the substrate profile with shallow and more frequent irrigations facilitated stratified substrates ty reach effective container capacity conditions (p < 0.0001n compared to non-stratified systems. The stratified systems took longer to leach all gravitational pores (p = 0.0266). In dry moisture conditions, non-stratified substrates were more hydrated when cyclic irrigation applications were applied compared to single applications (p = 0.0492). This study demonstrated that cyclic irrigation scheduling enhanced water retention in both non-stratified and stratified profiles under different initial moisture conditions and can be used as an irrigation strategy when dry substrate conditions prevail. [ABSTRACT FROM AUTHOR]

Hydrangea macrophylla exhibiting blue sepals (versus purple or pink) have improved marketability; however, little research has been conducted to evaluate aluminum (Al), the element responsible for bluing, on crop growth, effectiveness of bluing sepals, and characteristics of flower clusters in an outdoor nursery. This study compared substrate Al availability, crop growth, flower color, number, and size over a 56-week period in two locations. A polymer coated (90-day release) or ground aluminum sulfate [Al2(SO4)3; water soluble] was either incorporated into a non-limed pine bark substrate, applied to the surface of the substrate as a top dress, or as a routinely applied Al2(SO4)3 drench (low concn.) or applied once (high concn.). In general, application of Al increased plant foliar Al concentration, but also decreased substrate pore-water pH and increased electrical conductivity (EC) with varying effects based on the applied product's solubility and subsequent longevity. Aluminum sulfate increased the potential of Al phytotoxicity negatively affecting root morphology and creating an undesirable rhizosphere electrochemistry due to the pH being continually acidic, <4, and the EC being temporarily increased to >1.5 mS·cm−1. These suboptimal rhizosphere conditions resulted in a lower quality or smaller plant. No plants exhibited clear, deep blue flower cluster sought by consumers. Neither the effect of pore water pH or EC could, alone or in combination, account for the lack of plant vigor or blue flower clusters when substrate and foliar Al concentrations were adequate in flowering H. macrophylla. More research is needed to investigate the effect of pore-water electrochemical properties, possible mineral nutrient co-factors that provide Al synergisms or toxicity protections, and holistic plant health on ensuring blue coloration of a vigorous H. macrophylla. [ABSTRACT FROM AUTHOR]

Pennsylvania bittercress (Cardamine pensylvanica) and other bittercress (Cardamine) species are among the most common and difficult-to-control weed species in container nurseries, and they have been vouched in most counties in Florida. Preemergence herbicides can provide control, but concerns over potential resistance development, environmental issues, and crop injury problems associated with herbicide use create the need for alternative weed control methods to be explored. Previous studies have shown the potential of mulch materials for controlling weeds in nurseries, but their use along with preemergence herbicides has not been extensively investigated. To compare the effects of different mulch materials and herbicides on Pennsylvania bittercress control, a full factorial designed greenhouse study was conducted. Three mulch treatments including no mulch, pine (Pinus sp.) bark, and rice (Oryza sativa) hulls were evaluated with three herbicide treatments, including water (i.e., no herbicide), isoxaben, and prodiamine applied at label rates. Twenty-five seeds of Pennsylvania bittercress were sown on the surface of each container and emergence (percent), coverage (square centimeters), seedhead number, and biomass (grams) were measured. The results showed that Pennsylvania bittercress in containers mulched with rice hulls had the lowest emergence throughout the experiment. For coverage, seedhead, and biomass parameters, Pennsylvania bittercress seeded in rice hulls treatments had significantly lower coverage, fewer seedheads, and lower biomass compared with those in nonmulched or pine bark treatments, regardless of herbicide treatment. With isoxaben and the water check, nonmulched treatments had the highest coverage/seedhead/biomass, whereas with prodiamine, Pennsylvania bittercress in pine bark mulched containers had the highest coverage/seedhead/biomass. In conclusion, applying rice hulls alone can provide better Pennsylvania bittercress control compared with isoxaben or prodiamine applied alone.

Hexavalent chromium (Cr(VI)) is one of the most toxic heavy metals found in industrial wastewater, so many researchers are working to develop efficient and environmentally friendly removal methods. It has been reported that natural biomass and its derivatives can be used to treat wastewaters containing Cr(VI). However, biomass with sufficient Cr(VI) removal performance to replace the existing chemical method, which is cheap and simple, has not been reported yet. This study reports that inexpensive, abundant, and commercially available pine bark has the highest Cr(VI) removal capacity (i.e., 376.3 mg/g) compared to biomass reported elsewhere. This value is six times higher than the theoretical value of an inorganic reducing agent (iron(II) sulfate heptahydrate). The main mechanism of Cr(VI) removal by pine bark was clearly identified through kinetic experiments, Fourier-transform infrared spectrometer, and X-ray photoelectron spectroscopy analyses, which were used to study the compositions, functional groups, and bonding states of pine bark. It was found that pine bark consists of various acidic functional groups that can act as electron donors to promote the removal of Cr(VI) through redox reactions. In conclusion, pine bark may be a promising candidate for the removal of Cr(VI) from wastewater, owing to its excellent removal capacity.

Lignocellulosic biomass is an abundant resource that can be valorized for the production of bioenergy. However, studies aiming to quantify the amount of biogas production potential per km forest road are scarce in the literature. In this study, fresh pine needles, pine needle litter, pine branches, and pine bark were digested in batch reactors under mesophilic conditions after a grinding/milling pre-treatment. All samples were collected from a low-altitude Mediterranean Pinus forest (North Greece) adjacent to a category G forest road with a gentle slope. The methane yield of fresh pine needles was between 115 and 164 NmL g−1 volatile solids (VS), depending on the Pinus tree size. Pine needle litter produced a significantly lower methane yield (between 58 and 77 NmL g−1 VS), followed by pine bark (85 NmL g−1 VS) and pine branches (138 NmL g−1 VS). Considering the quantity of pine needle litter accumulated on adjacent forest roads (600 ± 200 g m−2), it was possible to calculate the biomethane production potential per km of forest road (up to 500 Nm3 km−1) if the biomass collected was disposed of at an anaerobic digestion facility. The results of the study demonstrate that residual forest biomass represents an additional resource for bioenergy production. Moreover, harvesting residual forest biomass can decrease the incidence of devastating summer forest fires and their disastrous consequences for the environment, the economy, and the local populations. [ABSTRACT FROM AUTHOR]

The physical, hydrological, and physico-chemical properties of horticultural substrates are influenced by particle shape and size. Sieve analysis has been the predominate method used to characterize the particle size distribution of horticultural substrates. However, the literature shows a diversity of techniques and procedures. The effects of agitation time and sample size on particle size distributions of soilless substrates were evaluated for several measures of sieve analysis, including sieve rate (a calculation of the percentage of material passed for each unit time of agitation), distribution median, SD, mass relative span, skewness, and kurtosis. To obtain the standard sieve rate (0.1%/min), pine bark, peat, perlite, and coir required agitation times of 4 minutes and 47 seconds, 7 minutes and 18 seconds, 10 minutes, and 11 minutes, respectively. However, there was concern that unwanted particle breakdown may occur during the particle size analysis of some materials. Therefore, a sieve rate (0.15%/min) for more friable materials was also determined. As a result, the endpoint of sieving was reached sooner for pine bark, peat, perlite, and coir, at 3 minutes and 10 seconds, 4 minutes and 42 seconds, 5 minutes and 14 seconds, and 6 minutes and 24 seconds, respectively. Increasing agitation time resulted in decreased distribution median, SD, and skewness for all materials. Sample sizes half and twice the volume of the recommended initial volume sieved did not change particle size distributions. For more precise characterization of particle size distributions when characterizing substrate components, agitation times and sample sizes should be specified for each material or collectively for all materials to ensure consistency and allow comparisons between results. [ABSTRACT FROM AUTHOR]

Substrate stratification is an emerging substrate management strategy involving layering multiple substrate materials within a single container to modify physiochemical characteristics of the substrate system. Specifically, stratifying allows growers and researchers to rearrange the air–water balance within a container to modify hydraulic characteristics. Moreover, fertilizer can be incorporated into just the upper strata to reduce leaching. Research to date has shown benefits associated with resource efficiency, production timing, and weed control. With the associated benefits for substrate stratification, interested growers will need pragmatic solutions for onsite trials. Therefore, the objective of this study was to identify a cost-effective solution for growers interested in exploring stratification options. As such, this research was designed to identify a single-screen bark separation to generate fine and coarse bark textures suitable for use as the top and bottom substrate strata. Loblolly pine bark (Pinus taeda) was screened with either a 4.0-mm, 1/4-inch, or 3/8-inch screen, with the particles passing through the screen (unders) separated from retained particles (overs). Stratified substrate systems were engineered with an individual screen wherein the fines were layered atop the coarse particles from the same screen. ‘Natchez’ crepe myrtle (Lagerstroemia indica) liners were planted in either of the three stratified substrate treatments or a nonstratified control. Substrate physical characteristics were assessed for each strata by pre- and postproduction properties to identify changes of substrate. The final growth index of the crop was unaffected by the substrate treatment (P = 0.90); however, stratified substrates did increase dry root weight (P = 0.02), with the smallest screen (4.0 mm) resulting in the greatest root weight. Separation of roots between the two strata indicated the presence of more roots in the upper strata in all substrates. However, the stratified substrates resulted in a greater shift in root location, encouraging increased rooting in the upper strata with fine particles, with the largest screen (3/8 inch) resulting in the greatest differentiation between upper and lower rooting. Each stratified treatment had increase in water-holding capacity in the lower (coarser) strata without changes in the upper strata. Thus, we conclude that single screens can be used to build stratified substrate systems. Moreover, screen aperture size may be used to achieve different outcomes with regard to root growth and development as well as water–air balance. Further research may indicate that screen selection may be used to target specific crop needs.

The physical, hydrological, and physico-chemical properties of horticultural substrates are influenced by particle shape and size. Sieve analysis has been the predominate method used to characterize the particle size distribution of horticultural substrates. However, the literature shows a diversity of techniques and procedures. The effects of agitation time and sample size on particle size distributions of soilless substrates were evaluated for several measures of sieve analysis, including sieve rate (a calculation of the percentage of material passed for each unit time of agitation), distribution median, sd, mass relative span, skewness, and kurtosis. To obtain the standard sieve rate (0.1%/min), pine bark, peat, perlite, and coir required agitation times of 4 minutes and 47 seconds, 7 minutes and 18 seconds, 10 minutes, and 11 minutes, respectively. However, there was concern that unwanted particle breakdown may occur during the particle size analysis of some materials. Therefore, a sieve rate (0.15%/min) for more friable materials was also determined. As a result, the endpoint of sieving was reached sooner for pine bark, peat, perlite, and coir, at 3 minutes and 10 seconds, 4 minutes and 42 seconds, 5 minutes and 14 seconds, and 6 minutes and 24 seconds, respectively. Increasing agitation time resulted in decreased distribution median, sd, and skewness for all materials. Sample sizes half and twice the volume of the recommended initial volume sieved did not change particle size distributions. For more precise characterization of particle size distributions when characterizing substrate components, agitation times and sample sizes should be specified for each material or collectively for all materials to ensure consistency and allow comparisons between results.