Green Residues Research Articles

Green manuring and crop residue management: Effect on soil organic carbon stock, aggregation, and system productivity in the foothills of Eastern Himalaya (India)

Improving soil quality, especially the organic carbon (C) accumulation and soil aggregation through economically and environmentally sustainable alternatives, is the need for hill agriculture. A five-year (2012–13 to 2016–17) field experiment was conducted with four green manure treatments [green gram (Vigna radiata); cowpea (Vigna unguiculata); sesbania (Sesbania aculeata) along with non-green manuring] and three cropping systems [groundnut (Arachis hypogaea) –pea (Pisum sativum); maize (Zea mays) –pea, and maize + groundnut – pea] involving two levels of residue management practices [residue removal and residue retention]. The experiment was laid out in a split–split plot design and replicated three times. After five years of experimentation, the results showed that among green manure treatments, Sesbania had a significant effect (p < 0.05) on total soil organic C, C pool, and surface (0–0.15 m) soil aggregation. The increase in C pool (p < 0.05) in Sesbania-treated soil was 43.2% in the very labile C, followed by 40.8% in the labile C relative to those without green-manure. In addition, the profile (0–0.45 m depth) weighted average organic C stocks in Sesbania-treated soils were higher in active (+29.3%), passive (+20.8%), and total (TOC: + 24.1%) forms than in non-green manure soils. Sesbania-treated soils also exhibited a higher C-Lability index, water stable macro-aggregates, and a higher aggregate ratio (AR) than non-green manure soils. Among the three cropping systems studied, inter-cropping of maize and groundnut followed by peas increased (p < 0.05) the stock of C pools, water-stable aggregates, and ARs in soil relative to the other two cropping systems. Residue retention also increased C pools, C-Lability Index, and microbial biomass C in soil compared to residue removal. Therefore, the incorporation of Sesbania into maize+groundnut-pea cropping systems with residue retention is a recommended option to improve soil quality and productivity of maize cropping systems in the Indian Himalayan region.

Fermentation with Tea Residues Enhances Antioxidant Activities and Polyphenol Contents in Kombucha Beverages.

Kombucha is a popular beverage with various bioactivities (such as antioxidant activity), which can be attributed to its abundant bioactive compounds, especially polyphenols. Kombucha is conventionally prepared by fermentation of a sugared black tea infusion without tea residue. In this study, the effects of black tea residue and green tea residue on kombucha were studied, and its antioxidant activities, total phenolic contents, as well as concentrations of polyphenols at different fermentation stages were evaluated using ferric-reducing antioxidant power, Trolox equivalent antioxidant capacity, Folin-Ciocalteu method and high-performance liquid chromatography with a photodiode array detector. The results showed that fermentation with tea residue could markedly increase antioxidant activities (maximum 3.25 times) as well as polyphenolic concentrations (5.68 times) of kombucha. In addition, green tea residue showed a stronger effect than black tea residue. Overall, it is interesting to find that fermentation with tea residues could be a better strategy to produce polyphenol-rich kombucha beverages.

Improving emulsification properties of alkaline protein extract from green tea residue by enzymatic methods

Alkaline extraction is an important process in the integrated biorefining of leafy biomass to obtain protein, but the resulting alkaline protein extract (APE11alkaline protein extract: APE.) may have poor emulsification properties for food applications. In this study, the components in the APE fractionations obtained by size exclusion chromatography were determined. The emulsification properties of APE were determined using oil/water with a ratio of 7:3. Whey protein and soybean protein isolate were used as controls while enzymes were used to improve APE's emulsification properties. The results showed that the APE could be divided into three fractions with protein content of 83, 56, and 34%. Carbohydrates mainly derived from homogalacturonan pectin were mostly in Fraction 2, while Fraction 3 consisted of peptides, oligosaccharides, and free polyphenols. The APE had similar emulsification capacity and emulsification stability as those of whey protein and soybean isolate. The emulsion made by the APE had a creaming index of 92% with emulsification activity index value of 44 m2 g−1, and these numbers could retain after storing at 25 °C for 15 days. The emulsification properties of the APE can be further improved by carbohydrate degradation. With the use of Viscozyme® L, the emulsification activity index value of treated APE was increased by 60%, and then still retained at 67 m2 g−1 after storing for 15 days. Treated by either pepsin or alkaline protease, the emulsification properties of APE were decreased, suggesting the key role of protein in APE for emulsification.

Fabrication of Ag-TiO2 functionalized activated carbon for dyes degradation based on tea residues

Being used as a renewable resource material, waste tea residues are usually applied in pollutants adsorption. However, it is a big challenge to effectively adsorb and degrade the pollutants at the same time in water resources. Herein, we proposed a strategy to prepare green tea residue derived activated carbon (g-AC), which was further used as substrates for loading Ag-TiO2 nanoparticles, forming a complex of Ag-TiO2/g-AC, to adsorb and degrade the dyes in wastewater. The study showed that Ag-TiO2/g-AC complexes behaved an excellent adsorption capacity of 479.5 mg g−1 and a high degradation efficiency of 95.9%. Also, the reusability of Ag-TiO2/g-AC in multiple cycles (n = 4, > 82.9%) revealed its good stability in the degradation process. This work, therefore, provides an alternative to recycle the tea industry-based wastes, offering a waste-to-green method for adsorbing and removing the pollutants in water.

Tomato leaves under stress: a comparison of stress response to mild abiotic stress between a cultivated and a wild tomato species

Tomato is one of the most produced crop plants on earth and growing in the fields and greenhouses all over the world. Breeding with known traits of wild species can enhance stress tolerance of cultivated crops. In this study, we investigated responses of the transcriptome as well as primary and secondary metabolites in leaves of a cultivated and a wild tomato to several abiotic stresses such as nitrogen deficiency, chilling or warmer temperatures, elevated light intensities and combinations thereof. The wild species responded different to varied temperature conditions compared to the cultivated tomato. Nitrogen deficiency caused the strongest responses and induced in particular the secondary metabolism in both species but to much higher extent in the cultivated tomato. Our study supports the potential of a targeted induction of valuable secondary metabolites in green residues of horticultural production, that will otherwise only be composted after fruit harvest. In particular, the cultivated tomato showed a strong induction in the group of mono caffeoylquinic acids in response to nitrogen deficiency. In addition, the observed differences in stress responses between cultivated and wild tomato can lead to new breeding targets for better stress tolerance.

Utilization of microalgae residue and isolated cellulose nanocrystals: A study on crystallization kinetics of poly(ɛ-caprolactone) bio-composites

Exploration of biodegradable materials for conventional application has taken a rising interest across the world. The presented work primarily focused on exploring the effectiveness of isolated CNCs from marine de-oiled green algae biomass residue (Dunaliella tertiolecta) in synthesized poly(ɛ-caprolactone) (PCL). The washed algae biomass residue (WABR) and algae derived CNCs were explored as two different bio-fillers incorporated into PCL for comparison and development of biodegradable and flexible bio-composites with varying bio-filler loading. FTIR, XRD, TGA, UTM, DSC, POM, and SAXS characterized the developed PCL/WABR and PCL/CNC bio-composites. Improved thermal stability was observed in PCL/CNC bio-composites by ~10 °C rise. Besides, increased modulus of 18.38 MPa and tensile strength was obtained in PCL/CNC/1 bio-composites. However, the isothermal kinetics study (at 45 °C) revealed the reduction in the degree of crystallinity of bio-composites, and the axialite formation was visualized via POM. Moreover, CNCs was found as an excellent nucleating agent and effective bio-filler as compared to WABR.

Cellulolytic enzymes behavior in delignified green coconut residues and enzymatic hydrolysis with enzyme recovery

Lignocellulosic bioconversion to obtain fermentable sugars often requires high enzyme dosages, increasing the total production cost. This study investigated the adsorption, desorption, and recycling of cellulases in enzymatic hydrolysis experiments using pretreated green coconut shell as substrate. The green coconut shell (GCS) was subjected to different pretreatments including dilute acid, alkaline, and two-stage acid-alkaline pretreatments. Adsorption and desorption studies involving cellulases from Trichoderma reesei ATCC 26921 and Cellic Ctec2 (10 FPU/g, initial dosage) with 5% solid loading showed that alkaline and two-stage acid-alkaline pretreatments were more suitable for enzyme recycling, because they showed lower values of cellulase adsorption capacity (48 % and 69 %) and higher values of cellulase recovery by desorption without Tween 80 addition (reaching 50 % using two-stage acid-alkaline pretreated GCS). Cellulases bound to the solid residue and dissolved in the supernatant after enzymatic hydrolysis can be reused for a new enzymatic hydrolysis process without compromising the sugar yield results. Using GCS as a substrate, the addition of solid residue and the supernatant from the previous step of adsorption of cellulases achieved a satisfactory sugar yield g/g (73.0 % for LCM1 and 60.0 % for LCM3) using less enzyme (just using recycled enzyme with no new enzyme added to the system) than the control case. Thus, it was possible to recycle the cellulases in two successive hydrolysis cycles with reduced enzyme load to achieve the same reducing sugar yields (up to 84 %), enabling cheaper and more efficient hydrolysis of lignocellulosic biomass.

Rapid detection of malachite green in fish and water based on the peroxidase-like activity of Fe3O4NPs enhanced with aptamer

This study attempted to fabricate a novel colorimetric method for the quantitative detection of malachite green (MG) residues in fish and water samples. Based on the recognition of the detection target and the enhancement of the peroxidase-like activities of Fe3O4NPs by MG-aptamer, a colorimetric method was established for MG detection. The detection limit (3α/κ, n = 9) was 16.7 μg kg–1, and the detection linear range was 0.06–2.38 μmol L–1. The recovery rates by standard addition in fish and water ranged from 90.1% to 119% with standard deviations (n = 3) of less than 6.6 %, and was well validated by a HPLC method. The detection procedure could be completed within 1 h. Therefore, the detection method was simple, stable, and reliable, and could be used to detect MG residues rapidly and accurately in fish and aquaculture water.

Durable and flexible Ag-nanowire-embedded PDMS films for the recyclable swabbing detection of malachite green residue in fruits and fingerprints

Swab sampling for the trace surface-enhanced Raman scattering (SERS) analysis of an aromatic dye (e.g., malachite green, MG) residue in fruits as well as fingerprints is promising due to its practical utility and efficiency in food security and forensic science. However, the durability and recyclability of the SERS substrates pose an enormous challenge. In this study, a novel flexible film was constructed by embedding a commercial Ag nanowire suspension into a polydimethylsiloxane film (Ag NWs@PDMS), which simultaneously exhibits SERS activity, durability and recyclability. High SERS performance was still maintained, even against 20 times stretchability, corrosion by HNO3, destruction by ultrasonication and a broad working temperature of −20 ℃ to 80 ℃. Excellent recyclability for MG sensing was achieved in ten cycles. Ag NWs@PDMS was successfully used for the quantitative detection of MG in juices of fruits (such as apple and pear) by drop dripping, with a limit of detection of 10 nM and good anti-interference. Meanwhile, the sensitive detection of the MG residue (only 3 ng/cm2) on fruits was enabled by the on-site surface swabbing by recycling for five cycles. Portable detection of the MG residue was further achieved from the 10th fingerprint after successively touching a dye drop onto the functional film combined with a portable Raman spectrometer.

Effects of different fertilization practices on anammox activity, abundance, and community compositions in a paddy soil

The return of crop residue and green manure into agricultural soil is known to be important agricultural management strategies, yet how they affect the anammox process remains poorly characterized. A field experiment containing four treatments: chemical fertilizer (F), F plus rice straw (FS), FS plus green manure (FSM), FSM with integrated management (FSMM), was performed to examine the effects of incorporation of rice straw and green manure residues on anammox. The results showed that the anammox activities in FS and FSM treatments (0.65 and 0.80 nmol N g−1 soil h−1, respectively) were significantly lower than those in F and FSMM treatments (1.60 and 1.28 nmol N g−1 soil h−1, respectively). Anammox contributed 4.07%–4.95% of total N loss in soil incorporated with residues, lower than soil treated with chemical fertilizer only (9.13%), the remaining being due to denitrification. However, the abundance of the hzsB gene (the hydrazine synthase β-subunit gene) in FS and FSM treatments (1.13 × 106 and 1.18 × 106 copies g−1 soil) were significantly higher than soil using chemical fertilizer only (7.49 × 105 copies g−1 soil) while showed no significant difference with FSMM treatment (8.81 × 105 copies g−1 soil). Illumina sequencing indicated that Brocadia was the dominant anammox genus, following by Scalindua and Kuenenia. Anammox bacterial diversity was altered after 4-year incorporation of rice straw and green manure, as shown by α-diversity indices. We concluded that rice straw and green manure incorporated with mineral fertilizer reduce N removal from paddy soil in terms of anammox in spite of stimulating anammox bacterial growth.

Utilization of Organic Mixed Biosludge from Pulp and Paper Industries and Green Waste as Carbon Sources in Blast Furnace Hot Metal Production

A six day industrial trial using hydrochar as part of the carbon source for hot metal production was performed in a production blast furnace (BF). The hydrochar came from two types of feedstocks, namely an organic mixed biosludge generated from pulp and paper production and an organic green waste residue. These sludges and residues were upgraded to hydrochar in the form of pellets by using a hydrothermal carbonization (HTC) technology. Then, the hydrochar pellets were pressed into briquettes together with commonly used briquetting material (in-plant fines such as fines from pellets and scraps, dust, etc. generated from the steel plant) and the briquettes were top charged into the blast furnace. In total, 418 tons of hydrochar briquettes were produced. The aim of the trials was to investigate the stability and productivity of the blast furnace during charging of these experimental briquettes. The results show that briquettes containing hydrochar from pulp and paper industries waste and green waste can partially be used for charging in blast furnaces together with conventional briquettes. Most of the technological parameters of the BF process, such as the production rate of hot metal (&lt;1.5% difference between reference days and trial days), amount of dust, fuel rate and amount of injected coal, amount of slag, as well as contents of FeO in slag and %C, %S and %P in the hot metal in the experimental trials were very similar compared to those in the reference periods (two days before and two days after the trials) without using these experimental charge materials. Thus, it was proven that hydrochar derived from various types of organic residues could be used for metallurgical applications. While in this trial campaign only small amounts of hydrochar were used, nevertheless, these positive results support our efforts to perform more in-depth investigations in this direction in the future.

Effects of wood ash, green residues and N-free fertiliser on naturally regenerated birch and field vegetation in a young Norway spruce stand in SW Sweden

ABSTRACT Treatments added to young conifer stands aiming to compensate for the loss of nutrients and alkalinity associated with whole-tree harvesting for bioenergy purposes have the potential to affect the growth of competitors to the conifers. Three different nutrient compensation treatments were applied to a young Picea abies (L.) Karst. stand in south-west Sweden, 2 or 3 years following final felling. The treatments were; fine fraction of harvest residues (15 Mg dw ha−1); granulated wood ash (4.1 Mg dw ha−1); nitrogen-free vitality fertiliser (twice 1.5 Mg ha−1); untreated control. Root biomass and total biomass of graminoids (mainly Deschampsia flexuosa (L.) Trin) were significantly greater in the wood ash and vitality fertiliser treatments than in the residues and control treatments. The aboveground and coarse root biomass of naturally regenerated birch (Betula spp.) and the aboveground biomass of dwarf shrubs (mainly Calluna vulgaris (L.) Hull.) and bottom layer were not affected by the treatments. Calcium and magnesium concentrations in the aboveground biomass of graminoids and phosphorus concentration in the biomass of bottom layer were significantly the highest in the vitality fertiliser treatment. Thus, nutrient compensation with vitality fertiliser or granulated wood ash may increase competition from graminoids in the establishment phase.

Detection of malachite green residue in aquaculture water by using a rare earth fluorescence probe

Detection of malachite green residue in aquaculture water by using a rare earth fluorescence probe

Activation of persulfate by green nano-zero-valent iron-loaded biochar for the removal of p-nitrophenol: Performance, mechanism and variables effects

In this study, with the green tea extraction solution as a reducing agent and green tea residues as a raw material of biochar, green nano zero-valent iron biochar (G-nZVI-BC) was prepared with the green synthesis method and then combined with potassium persulfate to degrade p-nitrophenol in water. Compared with zero-valent iron-loaded biochar (C-nZVI-BC) prepared by the traditional chemical liquid phase synthesis method, G-nZVI-BC containing tea polyphenols further improved dispersibility of Fe0 on biochar, prevented nZVI agglomeration on BC, and promoted PNP degradation. The system constructed by G-nZVI-BC/PDS showed the high oxidation resistance than the C-nZVI-BC/PDS system, thus endowing the synthesis material with long-term reactivity. Both the radical pathway and non-radical pathways contributed to catalytic degradation and free radicals played a key role. The G-nZVI-BC/PDS system realized the good removal effect on PNP in the pH range of 3.06–9.23. The reusability of G-nZVI-BC and the PNP removal effect in water body conditions indicated that G-nZVI-BC had a good application prospect in the field of water treatment.

Influence of tomato waste compost ratios on plant growth and fruit quality of cucumber and summer squash

ABSTRACT Peat-moss (Sphagnum spp.), is currently an expensive material and a nonrenewable resource with variable properties. Therefore, its use should be gradually reduced. Hence, there are numerous attempts aiming to reduce the use of peat-moss as a bulk substrate and to search for high-quality, locally available and low-cost alternatives to peat-moss. Therefore, the main objective of this research is to investigate the effect of partial replacing of peat-moss with tomato waste compost (TWC) on plant growth, productivity, fruit quality, and morphological features of two types of economic cucurbits species under greenhouse conditions. The plants were planted into pots containing different proportions of TWC (0%, 5%, 10%, 15%, 20% and 30%) with peat-moss, sand and clay as growing substrates. The results indicated that the plant height and the leaves number of both plants were significantly influenced by different substrate treatments. TWC ratios of 15% and 20% increased the amount of cucumber and summer squash fruit yield more than the commercial peat media but they had insignificant differences. Also, they were significantly improved fruit quality characteristics, particularly total soluble solid (TSS) and titratable acidity (TA) of crop fruits more than commercial peat-moss treatment. Implications: Because of the high price of peat-moss and that it is a non-renewable material, farmers resorted to using other alternatives, including green residue compost. Thus, the aim of this work is to reduce the use of peat-moss by replacing it with the use of lokw percentages of TWC. When tomato plant residues return to the soil by converting them into compost, this is a valuable agricultural practice to improve soil fertility and increase the organic matter of the soil as well as increase the source of nitrogen (N) that supports the growth of beneficial microorganisms.

Comparison of machine learning methods for dry biomass estimation based on green logging residues chips

ABSTRACT This work shows how modern machine learning techniques can be used to solve current problems faced by the forestry industry. More specifically, the focus is on comparing the predictive performance of several algorithms on estimating the dry weight, in tons, of chip residues. The dataset contains samples obtained during 22 months from 220 trucks coming from 17 different farms located within the area spanned by the Biobío and Maule regions, Chile. Once the trucks arrived, samples were collected and dried to compute the dry tons carried by each truck, which was set as the dependent variable. Using open-source software implementations of state-of-the-art algorithms it was possible to determine, for our data, that even though the non-parametric models Gradient Boosting Machines (GBM) and Neural Networks (NNET) outperformed the linear regression (LM) model, they are not statistically superior to the LASSO regression (GLMNET), an improved version of the LM model. Additionally, it was observed that seasonality affects the ratio of green tons to dry tons a truck can deliver to a power plant during the year. Finally, the continuous variables green tons, elevation, east and north (longitude-latitude) also contribute to explaining the dependent variable.

Wood-Based Compost Affects Soil Fertility and the Content of Available Forms of Nutrients in Vineyard and Field-Scale Agroecosystems

To counteract the loss of organic matter of agricultural soils, the use of compost from green and woody residues is a promising strategy. In this study, an organic farm (NE Italy) was investigated to determine the effect of management practices on physical and chemical soil properties. The organic system received three years ago a single high dose (60 t ha−1) of a wood-based compost (WBC), and it was compared with a conventional farm that annually managed mineral plus manure fertilization. In both systems, soil samples from a vineyard and field-scale rotation were collected, together with soil samples from an area not cultivated and not treated neither with compost nor with fertilizers or manure (untreated = control). Soil samples were characterized for soil fertility parameters, extractable fractions of macro- and micronutrients with DTPA and Mehlich3, and their total content. WBC was physically, chemically, and biologically characterized. The results showed that WBC fulfilled the requirements prescribed by Italian legislation, and the absence of phytotoxicity and conversely a stimulating activity towards root development was evidenced. From the DNA metabarcoding of the bacterial community, WBC revealed several peculiarities, including the dominance of taxa such as the order Acidimicrobiales, the families Anerolineaceae, Cytophagaceae, Caldimicrobiacese, Saprospiraceae and the archaeon Candidatus Nitrososphaera. Concerning the fertility of soils, the addition of WBC in both the vineyard and field-scale considerably affected some important soil parameters compared to those of conventional fertilization and untreated soil. Among these, WBC strongly increased the organic C content and the amount of the available P. In addition, the concentrations of macro- and micronutrients extractable by DTPA were generally higher with WBC than conventional fertilization. On the contrary, Mehlich3 extractable metals and total metals content were not affected by fertilization. The principal component analysis indicated that organic C, macronutrients (CaDTPA, KDTPA, and POlsen), as well as micronutrients (BDTPA, FeDTPA, and MoDTPA) are principal factors that properly separated conventional fertilization from organic fertilization. Beside this, within the same management, cases by agroecosystem were also well revealed by cluster analysis. In essence, in the short-term, the organic system led to a significant improvement in organic C and plant-available nutrients over the conventional system.

Effect of cellulose nanocrystals derived from Dunaliella tertiolecta marine green algae residue on crystallization behaviour of poly(lactic acid)

Marine green algae biomass residue (ABR), a waste by-product of Dunaliella tertiolecta, left behind after the extraction of oil from the algal biomass, was utilized for the fabrication of cellulose nanocrystals (CNCs). The fabricated sulphuric acid hydrolysed CNCs had needle-like morphology, with dominant cellulose type I polymorph and a high crystallinity index of 89 %. ICP-MS elemental analysis confirmed the presence of a variety of minerals in the ABR. Washed ABR (WABR)/PLA and CNC/PLA bio-composite films were developed via solvent casting technique with varying bio-filler loadings for comparing their effectiveness on the crystallization behaviour of PLA. FESEM, FTIR, XRD and TGA were used to characterize the bio-fillers. The nucleating and crystallization behaviour of the bio-composite films were confirmed using DSC, SAXS and POM analysis which indicated better effectiveness of CNCs with a significant reduction in cold crystallization temperature, and noteworthy increment in crystallinity and spherulite growth rate.

Elements of biologization to ensure high energy and economic efficiency of sugar beet growing under the conditions of the Podillia

Purpose. To study the ways of improving energy and economic efficiency of sugar beet cultivation based on the biological system of fertilizer grain-beet crop rotations under the conditions of sufficient moisture, the right-Bank forest-Steppe.&#x0D; Methods. Laboratory and field, statistical.&#x0D; Results. The results of studies on ways of improving energy and economic efficiency of sugar beet cultivation based on the biological system of fertilizers in grain-beet crop rotations under the conditions of sufficient moisture in the Right-Bank Forest-Steppe are presented, which included technology for sustainable cultivation of sugar beet under the conditions of an acute shortage of organic fertilizers. The technology includes the following elements of biologization: straw, green manure biomass was used as an alternative organic fertilizer directly under sowing of pre-crop. The positive results of increasing energy and economic efficiency of sugar beet is shown.&#x0D; Conclusions. In the acute shortage of organic fertilizers, it is required to use mineral fertilizers and basic elements of biologization, such as green manure, crop residues, and perennial grasses and legumes as pre-crops. This will contribute to the increase in the value of the gross output of feedstock, energy-economic viability and sustainability of agricultural systems in agronomic sense.

Determination of Malachite Green Residue in Aquatic Products Based on Three-Dimensional Fluorescence Spectrum

Determination of Malachite Green Residue in Aquatic Products Based on Three-Dimensional Fluorescence Spectrum