Paper Mulch Research Articles

Modification of polyvinyl alcohol with 2-hydroxypropionic acid and cross-linking with glutaraldehyde for the preparation of biodegradable mulch paper and its properties

Abstract The preparation of biodegradable mulch film with paper-based materials has become a significant focus in mulch film development due to the serious pollution caused by plastic mulch film. This study utilized the esterification cross-linking reaction of LA, PVA, and GA to coat the surface of paper as the substrate. FTIR, TGA, XRD, SEM, tensile testing, and oxygen, water vapor barrier performance tests were performed. The optimal conditions for film preparation were determined to be a 10 % PVA aqueous solution, 5 % GA content, and a PVA/LA/GA ratio of 1:2:1. The resulting film paper exhibited a dry strength of 6.52 kN/m, a wet strength of 0.23 kN/m, a tearing degree of 969.35 mN, a Cobb value of 12.04 g/m2, a water vapor transmission rate of 573.27 g m−2 24 h−1, and an oxygen transmission rate of 7.373 cm3 m−2 24 h−1. After a 6-week landfill degradation test, the film showed a degradation rate of 25.3 %, while still maintaining a tensile strength of 1.89 kN/m. Field application tests in greenhouses confirmed that the film paper facilitated the growth of strawberry, its mechanical and barrier properties suitable for a biodegradable paper mulch.

Performance of Some Organic Mulch Materials for Weed Suppression, Soil Conditions and Yield in Capsicum annuum L. Cultivation

The aim of this study was to investigate the effectiveness of different organic mulch materials and thicknesses in controlling weeds, improving soil temperature and moisture, and increasing crop yield in Capsicum annuum L. cultivation. The experiment was conducted in 2022, using three types of mulch materials (grass, chopped paper, wheat straw) and three different thicknesses (5 cm, 10 cm, 15 cm). A total of 22 weed species were identified in the experimental area, and statistical analysis revealed significant differences in all parameters between the mulch treatments and the control group. The use of organic mulch resulted in better weed control, with an increase in mulch thickness corresponding to greater suppression of annual weed species. The highest effect on weed dry weight was observed in the 15-cm paper mulch, which also produced the highest yield (3940.48 kg/da). The study also showed that soil temperature was lower and soil moisture was higher in all mulch treatments compared to the bare soil control group, with some fluctuations observed at times. Overall, the findings suggest that the use of organic mulch is crucial in arid and semi-arid regions for effective weed control, water conservation, improved water efficiency, reduced soil evaporation, and increased pepper yield.

Synthesis of lignin-based polyurethane (LPU) and fabrication of degradable mulch film through LPU coating on cellulose paper

The use of non-degradable plastic mulch film causes significant environmental pollution and poses a threat to human and ecological safety. To address this issue, a viable solution is to develop bio-based and biodegradable paper mulch films to replace non-biodegradable ones in agricultural soils. In this study, a green and straightforward process was used to synthesize lignin-based polyurethane (LPU), which was then coated on cellulose paper (CP) of low basis weight of 30 g/m2 to fabricate a composite LPU/CP mulch film. An ultra-thin and lightweight LPU/CP mulch film was successfully fabricated with basis weight, thickness, and specific density of 40 g/m2, 80 µm, and 0.5 g/cm3, respectively. It was observed that surface coating was very effective in improving the physical strength of composite film as indicated by the improvement of tensile index from 19.3 N·m/g of CP to 65.0 N·m/g of LPU/CP mulch film. Moreover, LPU/CP mulch film presented excellent water resistance properties as suggested by the water contact angle of 107° and the water vapor transmission rate of 639.3 g/m2·day. LPU/CP mulch film also shows a balance between degradability and durability that it starts to break down into fractions after being buried for 28 days as a result of microbiological degradation. This work provides a feasible technology for fabricating eco-friendly, cost-effective, and biodegradable paper mulch film.

Effect of Recycled Paper Mulching on Weed Occurrence, Growth and Yield in Rice

Effect of Recycled Paper Mulching on Weed Occurrence, Growth and Yield in Rice

Effects of Shredded Paper Mulch on Komatsuna Spinach under Three Soil Moisture Levels

Mulch has been considered effective for saving water and promoting plant growth. However, little has been investigated about the effect of mulch from recycled shredded paper under different soil moisture conditions on spinach growth. A pot-grown Komatsuna spinach experiment with a factorial design was conducted under two main conditions, with and without shredded paper mulch. Each of these conditions was treated with three different soil moisture levels (SWC) 20%, 25%, and 30%. The smallest evapotranspiration amount was in the mulch-only, no-plant treatment with SWC 20% (92.88 mm), and the largest was in the plant-only, no-mulch treatment (226.19 mm). All biomass yield attributions were negatively influenced by increasing the frequency of irrigation and SWC levels. SWC 20% with shredded mulch resulted in the largest dry matter, although it was statistically non-significant. But it resulted in taller plant heights and a larger leaf area index (LAI) compared to soil with no shredded mulch (p < 0.05). For SWC 25% and 30% treatments, Komatsuna spinach with no shredded mulch resulted in slightly superior plant dry matter and plant height, compared to mulched plants. These results suggest that SWC 20% with shredded paper mulch has the highest potential for saving water among all treatments for growing spinach under limited water availability.

Evapotranspiration and crop coefficient of Physalis peruviana cultivated with recycled paper as mulch

The application of soil mulching has been widely used to increase crop production; however, few research studies have comprehensively evaluated the use of recycled paper as soil mulch and its effects in relation to water savings and crop coefficients. The objective was to evaluate the effects of mulching with recycled paper on evaporation and evapotranspiration of Physalis peruviana and to determine the crop coefficients in its development stages. The study was carried out in two cultivation cycles at the Lysimetric Station of Viçosa, MG, Brazil. The experiments were set up in a randomized block design with four replicates, where four lysimeter treatments were applied: P. peruviana cultivation without recycled paper mulch (C); P. peruviana cultivation with recycled paper mulch (CP); lysimeter with only recycled paper mulch (P); and lysimeter cultivated with Bahiagrass (G). Irrigation and drainage volumes in each lysimeter were measured daily to calculate crop evapotranspiration (ETc), reference evapotranspiration (ETo) and, therefore, the crop coefficients (Kc). In addition, crop phenology, fruit characteristics, gas exchange, yield and normalized difference vegetation index (NDVI) were also evaluated. For the first cultivation cycle, over 218 days, the values of water consumption in the lysimeters C, CP, P and G were 405, 291, 88 and 444 mm, respectively. For the second cycle, over 206 days, the values of water consumption were 416, 279, 94 and 331 mm, respectively. Recycled paper significantly reduced water consumption, especially in the initial and late-season stages, also reducing Kc values. The Kc values for P. peruviana were 0.25, 0.55, 1.05 and 0.46 in cultivation with mulch and 0.45, 0.85, 1.35 and 0.48 in cultivation without mulch for the initial, development, mid-season and late-season stages, respectively. NDVI can be used to estimate the Kc values of P. peruviana. Recycled paper mulch reduced water consumption by 30.6% and increased gas exchange and yield of P. peruviana in cycles 1 and 2, respectively.

Insights into the abiotic fragmentation of biodegradable mulches under accelerated weathering conditions

Biodegradable mulches (BMs) can be tilled into soils to mitigate disposal and environmental problems. However, the content of biodegradable microplastics (BMPs) would increase with the addition of biodegradable macroplastics (BMaPs). The fragmented particles have a strong affinity to soil pollutants, having the potential to transfer via the terrestrial food web in an agroecosystem. Based on the spectral analysis and particle size analysis, this study explored the physicochemical characteristics of weathered BMaPs and BMP-derived dissolved organic matter (DOMBMP). Ultraviolet (UV) irradiation reduced the mechanical strength of BMaPs and induced oxygenated functional groups, thus increasing surface roughness and hydrophilicity. This promoted the adsorption of aromatic compounds and heavy metals from soils to BMPs. After entering the water environment, the pH of the solution with DOMBMP decreased, whereas the concentration of dissolved organic carbon (DOC) increased. Compared with paper mulch, bioplastic mulch contributed a higher amount of DOMBMP, such as aromatic structure-containing chemicals and carboxylic acids, to the water environment but released fewer and smaller plastic particles. The findings from this study can help manage environmental risks and determine disposal strategies after the use of mulching.

Influence of mulches on yield and quality of Strawberry (Fragaria x ananassa Duch.) cv. Chandler

The quality of strawberry is highly hampered by improper crop management, which can only be solved by using different types of mulches. It is very rare in literature, where the different types of mulches are used for the quality assessment. To carry out this new strategy to sustain the quality of strawberry the present study was carried out using various kind of mulches viz., white polythene mulch, yellow polythene mulch, black polythene much, green polythene mulch, news-paper mulch, wood husk mulch, serpat grass mulch, red polythene mulch, jute bag mulch comprised of 10 treatments and 3 replications under the randomized block design. The findings revealed that the application of black plastic mulch significantly increased the total number of fruit (12.67), length of fruit (6.21 cm), width of fruit (4.20 cm), weight of fruit (16.30 g), yield plant-1 (200.10g), yield plot-1 (3.20kg), total soluble solids (11.85%), total sugar (8.58%), reducing sugar (7.90%), non-reducing sugar (1.75%) and vitamin C (45.91 mg 100g-1). It is pertinent to infer that the application of the mulches (either black or yellow) performed and better over control.

Biodegradable Recycled Paper Mulch Reduces Strawberry Water Consumption and Crop Coefficient

Mulching with recycled paper has the potential to be used in agricultural production and can be adopted in strawberry cultivation. Therefore, the objective of this study was to evaluate the agronomic characteristics, water consumption and technical coefficients of strawberry cultivated with recycled paper as mulch. The treatments consisted of strawberry cultivation in lysimeters with recycled paper mulch and without soil cover. The recycled paper used was 187 μm-thick. The irrigation system was installed with drippers whose flow rate was 2 L h−1. Strawberry irrigation requirements were 317 and 394 mm, with and without mulch, respectively. Mulching with recycled paper did not have a significant effect on the average number of fruits, fresh fruit mass, fruit waste per plant, average fruit yield and water productivity. In relation to the technical coefficients, maximum values of the evaporation coefficient (Ke) of 0.40 (calculated with the evapotranspiration of the grass—L) and 0.28 (calculated with the Penman–Monteith ETo—PM) were obtained for OPM. The Kc values for the initial and full development stages were 0.31 and 0.84 (L) and 0.24 and 0.66 (PM), respectively. NDVI can be used to estimate strawberry Kc values. Recycled paper as mulch reduces the water consumption of strawberry crops and does not alter the agronomic characteristics.

Impact of buried debris from agricultural biodegradable plastic mulches on two horticultural crop plants: Tomato and lettuce

Biodegradable mulches (BDM) are increasingly valued and used for substituting non-biodegradable plastic mulches polluting agricultural soils. They are tilled into soil, where they fragment and release compounds throughout their biodegradation. The consequences of BDM use on the plant-soil environment have been partially studied with pristine and with artificially-weathered BDM fragments. However, to guarantee safety use of BDM, studies on the BDM debris effects are required. For this, to determine potential effects of the field-weathering BDM on plants, a mesocosm experiment was performed by sowing seeds from two major plant species commonly cultivated with BDM, tomato (Lycopersicon esculentum) and lettuce (Lactuca sativa), in plant pots containing pristine and field-weathered pieces from seven different BDM formulations, one paper mulch, a polyethylene (PE) mulch, and no-mulch control pots.Germination of both plant species was unaffected by any of the mulch treatments; however, PHB (polyhydroxybutyrate)-based BDM fragments severely inhibited tomato and lettuce plant growth, 90 and 95 %, respectively. Moreover, all pristine and field-weathered BDM significantly delayed lettuce plant development. Tomato plant growth progressed better, but growth retardation was also evidenced with most field-weathered BDM treatments. Overall, field-weathered fragments caused stronger effects on plants than the pristine unused ones. No effects were found for PE mulch, either pristine or field-weathered. The obtained results highlight that BDM debris may alter plant development depending on their nature and on their weathering, rather than on their physical presence, and evidence the need to conduct further experiments on the impact of field-weathered BDM on the plant-soil environment.

The Use of Different Waste Mulch Materials Against Weeds Which are Problems in Tomato (Solanum lycopersicum L.) Cultivation

Study was carried out in two different locations (L1: Yüzbaşılar village and L2: TUAM (Iğdır University Agricultural Application and Research Center) in 2020 to determine the effect of different waste mulch materials on weed control and tomato yield. In the study, five different mulch materials (tree of heaven, fine sawdust, wood chips, shredded paper and sheep wool) were used. Each plot has weed and weed-free control group. The effects of mulching on weeding, weed dry weight, yield (kg/da), fruit weight (gr) and number of fruit per plant (pieces) were investigated. Three counts were made to determine the weed density in the plots. As a result of the study, a total of 17 weed species belonging to 9 families were determined in the experimental areas. As a result of the counts, it was observed that Sorghum halepense L., Convolvulus arvensis L. and Xanthium strumarium L. weeds emerged the most in the plots where the mulch materials were laid. Depending on the location, the lowest density among the weed density counts was obtained from the paper plots. In the study, the lowest average weed dry weight among the mulch materials was paper (L1: 97.63; L2: 73.12 gr/m2), the highest average was tree of paradise (L1: 191.87; L2: 165.27 gr/m2) plots. As a result of the study, the best results in tomato yield (L1: 6.078.50; L2: 6.807.87 kg/da) and fruit weight (L1: 142.67; L2: 147.35 gr)) were obtained in the use of paper mulch. The highest number of fruits per plant was obtained in the use of wood chips (L1: 45.774.83/ pieces) and tree of heaven leaves (L2: 46.627.41/pieces). The fact that mulch applications give better results than control groups suggests that mulches will be much more beneficial for controlling weeds and improving fruit yield and quality.

Substitution Experiment of Biodegradable Paper Mulching Film and White Plastic Mulching Film in Hexi Oasis Irrigation Area

Biodegradable paper mulch has the advantages of being easily degradable and environmentally benign, but its own performance and adaptability to harsh environments have not been tested. This paper uses scanning electron microscopy and three-dimensional morphometry to microscopically characterize biodegradable paper mulch and white plastic mulch. To analyze and compare their mechanical and hydrophobic properties, and weather resistance, the two mulches were measured through tensile tear load and static contact angle. A comparative analysis of the effect of mulching in the dry crop area of the Hexi Corridor was conducted by comparing the growth index, farm water heat, soil oxygen content, and yield using maize and flax. The test results show that biodegradable paper mulch films were slightly inferior to traditional white mulch films in terms of mechanical and hydrophobic properties, with inadequate insulation and moisture retention, but better in terms of aging resistance, soil oxygen content, and crop insulation and water storage capacity in the middle and growth stages. White mulch film had a better yield enhancement effect on maize, while with biodegradable paper mulch film, this was more significant with flax.

Differential gas exchange and soil microclimate dynamics under biodegradable plastic, polyethylene, and paper mulches

Biodegradable plastic mulch is potentially a suitable alternative to conventional polyethylene mulch because of the limited disposal options of the latter. However, biodegradable plastic mulch must perform better or comparably to polyethylene mulch to be widely adopted. Gas exchange and soil microclimate are important factors impacted by the use of plastic mulch, which in turn have implications on crop productivity. A controlled-environment study was established in a greenhouse to assess gas exchange and soil microclimate dynamics under biodegradable plastic, polyethylene, and paper mulches with and without planting holes, as well as the impact of the mulches on the growth of sweet corn (Zea mays). A no-mulch condition was included as control. In addition, we monitored CO2 concentrations in the vicinity of planting holes (chimney effect) in a greenhouse and agricultural field conditions under sweet corn production. The plastic mulches (both biodegradable plastic and polyethylene mulches) decreased the soil O2concentration to a minimum of 181–183 mmol mol-1, and when compared to the no-mulch, the plastic mulches reduced water loss within 50 days by 35–68 mm. The paper mulch inhibited light penetration more than did the plastic mulches. There was an increase in the CO2 concentration at 2.5 cm above the planting holes in the plastic mulches compared to that under the no-mulch. However, the differences were not discernible at 15 cm above the ground. Consequently, we did not observe significant impacts on the growth of sweet corn, possibly, because the canopy height of sweet corn was more than 15 cm within a few days after planting. Overall, the plastic mulches did not reduce O2 concentration below 100 mmol mol-1, the minimum level in which plant growth becomes impaired. Also, the often reported improved growth of sweet corn from plastic mulching could be attributable to other factors, such as weed control, reduced water loss, and early season soil warming, rather than elevated CO2 concentrations and fluxes in the vicinity of planting holes. Highlights- Gas exchange and soil microclimate dynamics under biodegradable plastic, polyethylene, and paper mulches were assessed - Elevated CO2 levels were observed near planting holes of plastic mulches (both biodegradable and polyethylene) - The plastic mulches inhibited O2 exchange, but not to a level that could impair plant growth - Polyethylene mulch conserved soil water better than biodegradable plastic and paper mulches - Paper mulch inhibited light penetration better than plastic mulches

Stomatal and photosynthetic responses of soybean with two types of mulch under different soil water conditions

Soybean was planted in clay pots with living mulch of white clover (CL) or shredded paper mulch (SP). Soil moisture in the pots was individually controlled at five levels from around 20% of volumetric soil water content (SWC) to near-saturated, by monitoring SWC every morning and irrigating intermittently. This study focussed on the growth period of the soybean when plant height and LAI reached around maximum. The lower evapotranspiration (ET) and lower stomatal conductance (gs) of the soybean in lower SWC with both SP and CL were caused by water stress. The significantly higher ET but lower gs for CL compared with SP at the same SWC levels revealed that the soybean with CL competed with the clover for water and that the clover extracted water even at the lower SWC. The lowest electron transport rate (ETR) and non-photochemical quenching (NPQ) at the lowest SWC level with both SP and CL were regarded as being caused by water stress, under which the thermal dissipation processes could not be activated under strong light with photoinhibition. The lower ETR and the higher NPQ under the low PPFD condition for CL compared with SP could be interpreted as the soybean with CL having both water and nutrient stresses, even under the low PPFD condition, but the soybean with CL activated NPQ to protect PhSII by reaching the maximum NPQ under lower PPFD compared with the soybean with SP. The lower photosynthetic rate (P) of the soybean at the lower SWC level for both SP and CL resulted from the lower gs and ETR caused by water stress. The lower P for CL compared with SP at the same SWC level resulted from the lower gs and ETR and severer photoinhibition despite the activated function of NPQ caused by the water stress and by the nutrient stress.

Humic and Acetic Acids Have the Potential to Enhance Deterioration of Select Plastic Soil-Biodegradable Mulches in a Mediterranean Climate

The perceived variability of plastic soil-biodegradable mulch (BDM) degradation has generated concerns about its functionality and sustainability, especially in climates and regions where biodegradation may be limited. This study evaluated the effects of surface-applied products (compost tea, dairy-based compost, humic and acetic acids) on the surface deterioration and visible degradation of three plastic BDMs (BASF 0.6, Novamont 0.6, and Novamont 0.7) and one cellulose paper mulch (WeedGuard Plus) in a Mediterranean climate. Deterioration was monitored for 10 months, and degradation was evaluated 6- and 12 months following soil incorporation. Deterioration varied between the two years of the study; however, the average deterioration for WeedGuard Plus reached 100%, BASF 0.6 and Novamont 0.6 achieved ≥80%, while Novamont 0.7 reached ≥70%. Application of humic and acetic acids increased BASF 0.6 deterioration, but only humic acid increased Novamont 0.7 deterioration. Scanning electron microscopy of mulch surfaces demonstrated evidence of microbial colonization; however, the surface-applied products did not enhance microbial counts. In-soil degradation of BDMs was inconsistent, but faster degradation occurred overall for starch- and polybutylene adipate-co-terephthalate (PBAT)-based BDMs. Future studies should continue to explore on-farm strategies to enhance in-soil degradation to meet the production system’s goals.

The Effects of Zinc Oxide/Silicon Dioxide Composite Coating on Surface Wettability and the Mechanical Properties of Paper Mulching Film

In order to improve the hydrophobic and mechanical properties of paper mulch film, ZnO/SiO2 composite coated paper mulch film was prepared with a brush coating method. Hydrophobicity and durability of the original paper mulch film and the coated paper mulch film were measured by static contact angle and mechanical torsion tests, and the mechanical properties of the two kinds of paper mulch films were measured by tensile and tear tests at different temperatures. The two kinds of paper mulch films were characterized by their micro-morphology and surface element distribution. The results show that the contact angle of the ZnO/SiO2 composite coated paper mulch film reaches 161.46°, and the contact angle can still reach 153.15° after 80 mechanical torsion cycles, which shows good superhydrophobic and hydrophobic durability. Compared with the original paper mulch film, the mechanical properties of the coated paper mulch film are also improved to some extent. Combined with the surface micro-morphology, it is found that a ZnO/SiO2 composite coating fills the pores between fibers in the paper mulch film and promotes the adhesion between fibers, thus improving the hydrophobicity, durability, and mechanical properties of the paper mulch film.

Impact of different mulching treatments on weed flora and productivity of maize (Zea mays L.) and sunflower (Helianthus annuus L.)

The concerns on weed control through herbicides are increasing due to their negative impacts on environment and human health. Therefore, alternative weed management methods are inevitable for sustainable crop production and lowering the negative consequences of herbicides. Mulching is an environment-friendly weed management approach capable of substituting herbicides to significant extent. Therefore, this study evaluated the role of different mulching treatments on suppressing weed flora in maize (Zea mays L.) and sunflower (Helianthus annuus L.) crops. Furthermore, the impact of different mulching treatments on the productivity of both crops was also investigated. Three mulch treatments, i.e., plastic mulch (PLM), sorghum mulch (SM) and paper mulch (PM) along with two controls, i.e., weed-free (WF) and weedy-check (WC) were included in the study. Different mulch treatments significantly altered weed flora in both crops. The PLM and PM resulted in the highest suppression (43–47%) of weed flora compared to WC treatment in both crops. The highest and the lowest weed diversity was recorded for WC and WF treatments, respectively. Different allometric traits, i.e., leaf area index, crop growth rate and root length of both crops were significantly improved by PLM as compared to the WC. Overall, maize crop recorded higher density of individual and total weeds compared to sunflower with WC treatment. The density of individual and total weeds was significantly lowered by PLM compared to WC treatment in both crops. Similarly, higher growth and yield-related traits of both crops were noted with PLM compared to the rest of the mulching treatments. Results of the current study warrant that PLM could suppress weed flora and improve the productivity of both crops. However, PLM alone could not provide 100% control over weed flora; therefore, it should be combined with other weed management approaches for successful weed control in both crops.

Preparation of eco-friendly cryogel absorbent/paper mulch composite with cellulose/ZnCl2 gel as adhesive

Application of polyethylene (PE) mulch in agriculture and horticulture is challenging due to scarce fossil-oil resources and serious environmental pollution. Therefore, bio-based mulches represent a promising alternative for petroleum-derived ones. From the lignocellulose from the whole corn stalk, the eco-benign cryogel absorbent and paper mulch has been modified by tartaric acid (TA) esterification and polyvinyl alcohol (PVA)/cationic starch (CSt) coating, respectively. This work reports a hybrid mulch of these two products via cellulosic partial-dissolution and regeneration processes and its excellent performance of water preservation for cultivation soil. The modification of TA molecules onto cellulose chains were confirmed by FTIR and X-ray diffraction, which showed the formation of ester bonds and crystallinity transition from cellulose I to the coexistence of cellulose II. SEM analyses proved a successful composite of TA-esterified cellulose absorbent and PVA/CSt-coated paper by ZnCl2-dissolved cellulose gel. The abundant H-bonding between interfaces of the coated paper and cellulose-derivative cryogel contributed to the favorable connection and thus mechanical properties, which both dry tensile strength (41.5 MPa) and wet tensile strength (35.6 MPa). The composites showed the reduction of water vapor transmission rate (WVTR) and oxygen transmission rate (OTR), which were 755.43 g/m2 day and 10.6 mL/m2/day, respectively, and enhancement of water absorbency for 210.3 g/g as increasing the cryogel thickness. The green and biodegradable strategy proposed in this study will broaden the application range of composite mulches in agriculture and forestry.

IRRIGATION MANAGEMENT AND BIODEGRADABLE MULCHING IMPACT ON CARROT BIOMETRIC CHARACTERISTICS AND YIELD

This study aimed to evaluate the biometric and productive characteristics of carrot (Daucus carota L.) under different irrigation levels and soil covers. Experiments were carried out at the Federal University of Viçosa in 2019 and 2020, to evaluate the effect of five irrigation levels (20, 40, 60, 80, and 100% of the daily irrigation depth) and soil coverings (control, plastic mulching, and paper mulching), on the variables soil moisture (U), actual water consumption (AWC), root length (R) and diameter (D), leaf height (H) and temperature (T), normalized difference vegetation index (NDVI), yield (Y) and dry root biomass (DB). Irrigation management was performed with tensiometers. There was no significant interaction (P < 0.05) between the factors. Irrigation significantly influenced D, H, T, NDVI, Y, and DB, while the soil cover treatment affected R, D, H, NDVI, Y, and DB. The highest yields were found in 100% irrigation (34.89 t ha-1) and with paper mulching (30.55 t ha-1). The results can guide future adaptations to the carrot production system currently in force in Brazil. As for biometric characteristics, yield, and sustainability in the use of water for irrigation were studied.

Can hemp hurd or paper mulch and biochar application improve weed management in matted-row strawberry production systems?

AbstractDuring 2015 and 2016, studies were conducted at Absaraka and Dickinson, North Dakota to evaluate the impacts of hemp (applied at 1156 m3 ha−1) and commercial paper mulch, as well as soil-applied biochar (applied at 11.25 m3 ha−1), on weed suppression and strawberry growth during the establishment year, and on weed suppression and strawberry yield during the production year, in a matted row production (MRP) system. During 2015, biochar influenced dry weed biomass only within the hemp mulch, with slightly more weed biomass associated with biochar application compared to zero biochar (3.1 vs 0.4 g m−2), suggesting that biochar may have increased weed germination and/or emergence from beneath hemp mulch. Biochar application also slightly increased soil pH, from 6.9 in non-amended soil to 7.0 in amended soil. Strawberry runner number during 2015 was greater in association with hemp or paper mulch compared to zero mulch (4.5 and 4.9 vs 2.4 runners plant −1, respectively). This result mirrored a similar differential in per berry mass across sites (7.6 and 7.4 vs 6.2 g berry −1 for hemp mulch, paper mulch and zero mulch, respectively). These results may be related to hemp and paper mulch reducing maximum soil temperatures during summer 2015. During the establishment year, both hemp and paper mulch suppressed weeds well compared to zero mulch, although at Absaraka hemp mulch provided slightly better weed suppression than paper mulch. During the production year, both mulches continued to suppress weeds compared to zero mulch at Dickinson. However, at Absaraka, only hemp mulch provided weed suppression compared to zero mulch, possibly because of faster paper degradation caused by greater numbers of large precipitation events and greater relative humidity at Absaraka compared to Dickinson. Weeds were removed from plots during 2015 to allow separation of weed suppression from other possible mulch impacts; therefore, yield data do not reveal striking differences among mulch treatments. Because previous research has demonstrated the impact of weed management during the establishment of strawberries in a matted row system, we concluded that hemp mulch may provide more durable weed suppression compared to paper mulch, which would increase strawberry yield protection in an MRP system. Material cost may be an issue for implementing hemp mulch, as hemp hurd cost was 25 times paper mulch at the application rates used in this study. However, hemp mulch could still be a beneficial option, especially for organic strawberry growers desiring a renewable and environmentally sound replacement for plastic mulch who are able to find affordable local sources of this material.