Effects of Plastic Film Mulching on Physical Characters of Soil and Yield and Yield Components of Sweet Potato

Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.

Effects of Different Plastic films Mulching on Soil Temperature and Moisture, the Growth and Yield of Sugarcane

[Objective] The effects of different plastic films mulching on soil temperature and moisture, and growth and yield of sugarcane were discussed in order to provide references for using different plastic film in sugarcane pro-duction. [Method]Four kinds of plastic films viz., normal colorless transparent plastic film, milky photodegradation weeding plastic film, black plastic film and gray-black plastic film were used in sugarcane cultivation by using no film mulching as the control. Soil temperature and moisture were measured during plastic film mulching period, and sugarcane agronomic traits such as emergence rate, tillering rate, plant hight, stalk diameter and effective stalk number were investigated during growth period, the cane yield and economic benefits were calculated during harvest period. [Result] The results showed that plastic film mulching could significantly increase soil temperature and moisture. Com-pared with the control, soil temperature was increased by 0.3-0.8 ℃ in three plastic films mulching treatment except for gray-black plastic film mulching. The soil moisture of all mulching treatments was 10.1%-17.4% higher than the control. Furthermore, the seedling emergence rate, tillering rate, effective stalk number and cane yield also could be improved using plastic film mulching,which were increased by 0.8%-9.9%, 20.6%-34.9%, 5190-10980 stalks/hm^2and6.4%-14.9% as compared to the control,while plant height and stalk diameter were found to be no significant effect by plastic film mulching. The results of benefit analysis indicated that, milky photodegradation weeding film mulching had the highest economic benefit, the second were normal colorless transparent plastic film mulching and black plastic film mulching, which were 5 987.2, 1 876.5 and 1 813.5 Yuan/hm^2 higher than the control. The gray-black film mulching treatment had poor benefit.[Conclusion] The milky photodegradation weeding plastic film could be vigorously extended in sugarcane production. Normal colorless transparent plastic film and black plastic film could be ex-tended gradually as a new kind of plastic film. The grayblack film should not be used for its higher cost and more thickness.

Effects of Planting Density, Duration of Disclosing Plastic Film and Nitrogen Fertilization on the Growth Dynamics of Rapeseed under No-tillage Cultivation

[ Objective] This study was to understend the optimized combination of planting density, duration of disclosing plastic film and nitrogen fertilization under no-tillage cultivation. [ Method] Quadratic polynomial regression and saturated D-optimal design were employed to investigate the effects of planting density, duration of disclosing plastic film and nitrogen fertilization on the dynamics growth of rapeseed under no-tillage cultivation.[ Result] Within the experimental range, the growth dynamics of no-tillage cultivated rapeseed assumed a rise-fall tend. For the effects to the growth dynamics of no-tillage cultivated rapeseed, nitrogen application amount was higher than planting density and duration of disclosing plastic film. The interaction effect between planting density and duration of disclosing plastic film was higher than that between nitrogen application amount and planting density, and between nitrogen application amount and duration of disclosing plastic film. [ Conclusion] The optimized combination of these factors for dynamic growth of rapeseed under no-tillage cultivation was determined to be： planting density of per hectare 154 925 individuals, duration of disclosing plastic film of 110 d, nitrogen application amount of 315 kg/hm^2.

Effects of Water-permeability Plastic Film Mulching plus Bunch Planting on Root and Yield of Foxtail Millet

Effects of water-permeability plastic film plus bunch planting on root growth and development and yield of foxtail millet were studied by randomized block design. The results showed that water-permeability plastic film mulching plus bunch planting had a significant promoting effect on root growth and development and yield of foxtail millet. Compared with the CK, the total root length, total surface area, total root volume and number of. root tips increased by 51.30%, 47.89%, 48.39% and 41.63%, respectively. The yield increased by 48.57%, and there was significant positive correlation between root length, total surface area, total volume, number of root tips and dry matter weight of roots with yield. Developed roots are the main reason for the yield increasing effect of water-permeability plastic film mulching plus bunch planting.

Light Simplified Foxtail Millet Cultivation Technique Adopting Furrow Sowing beside Plastic Film Covering Micro-ridges

In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with the characteristics of low instable yield, manual thinning and weeding, high labor intensity, and labor and time saving, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated furrow sowing beside plastic film covering micro-ridges, simplified cultivation and mechanized production, forming the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges. This study introduced the technique points of the simplified foxtail millet cultivation technique adopting furrow sowing beside plastic film covering micro-ridges, including preparation before sowing,sowing, attached agricultural machines, field management, harvest and residual film recovery.

PCR-DGGE Analysis of Bacterial Communities Structure in Babylonia areolata Culture Systems of The Subtidal Zone and The Pond Mulched Plastic Film and Sand in Bottom

To know the bacterial communities structure in Babylonia areolata culture systems and to research and optimize the management pattem of Babylonia areola-ta culture systems of the pond mulched plastic film and sand in bottom, the bacte- rial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom were analyzed at molecular level by adopting the denaturing gradient gel electrophoresis （DGGE）. The results indicated that the dominant bacterial communities in Babylonia areolata culture systems of the sub-tidal zone and the pond mulched plastic film and sand in bottom, which were built on the basis of the seawater in East-island of Zhanjiang, included Proteobac- teda Chloroflexi, Cyanobacteria and Actinobacteria. The dominant bacterial groups in the above pond culture system were Garnmaproteobacteria, Alphaproteobacteria, Deltaprotecbacteda, Epsilonproteobacteda, Anaerolineae, Cyanobacteria and Acti- nobacteda. The dominant bacterial communities in the subtidal zone culture system were Gammaprotecbacteda, Alphaproteobacteria, Deltaproteobacteria, Anaerolineae and Cyanobacteda, and there were less Epsilonproteobacteria and Actinobacteria in the culture system. The higher diversity was detected in the above two culture sys- tems. The results of unweighted pair group method with arithmetic average （UPG- MA） showed that the bacterial communities of the sediment samples S1 and S2 in the above two culture systems were a cluster, the similarity of bacterial communities was 54.5%. The bacterial communities of seawater samples S3 and S4 in the above culture systems were in clusters, and the similarity of the bacterial communi- ties was 84.0%. The results showed that the microorganism ecological level in the Babylonia areolata culture systems of the pond mulched plastic film and sand in bottom could be similar to the sub-tidal zone culture systems through changing the pond seawater and monitoring the microbial population.

Analysis of Phthalate Esters in Air, Soil and Plants in Plastic Film Greenhouse

The phthalate esters such as DMP, DEP, DBP and DEHP in air, soil and plant samples in plastic film greenhouse were clean up with fine silica gel column and determined with HPLC. It was found that the concentrations of PEs in air and soil samples in plastic film greenhouse are much higher than those of contrast samples. But concentrations of PEs in plants in plastic film greenhouse are not remarkably affected by the pollution of air and soil.

Effects of plastic film mulching on soil greenhouse gases(CO2,CH4 and N2O) concentration within soil profiles in maize fields on the Loess Plateau,China

To better understand the effects of plastic film mulching on soil greenhouse gases（GHGs） emissions,we compared seasonal and vertical variations of GHG concentrations at seven soil depths in maize（Zea mays L.） fields at Changwu station in Shaanxi,a semi-humid region,between 2012 and 2013.Gas samples were taken simultaneously every one week from non-mulched（BP） and plastic film-mulched（FM） field plots.The results showed that the concentration of GHGs varied distinctly at the soil-atmosphere interface and in the soil profile during the maize growing season（MS）.Both carbon dioxide（CO_2） and nitrous oxide（N_2O） concentrations increased with increasement of soil depth,while the methane（CH_4）concentrations decreased with increasement of soil depth.A strong seasonal variation pattern was found for CO_2 and N_2O concentrations,as compared to an inconspicuous seasonal variation of CH_4 concentrations.The mean CO_2 and N_2O concentrations were higher,but the mean CH_4 concentration in the soil profiles was lower in the FM plots than in the BP plots.The results of this study suggested that plastic film mulching significantly increased the potential emissions of CO_2and N_2O from the soil,and promoted CH_4 absorption by the soil,particularly during the MS.

Response of carbon footprint to plastic film mulch application in spring maize production and mitigation strategy

Producing more food with a lower environmental cost is one of the most crucial challenges worldwide. Plastic mulching has developed as one of the most dominant practices to improve crop yields, however its impacts on greenhouse gas(GHG) emissions during the production life cycle of a crop are still unclear. The objective of this work is to quantify the impacts of plastic film on GHG emissions and to reduce GHG emissions with innovative agronomic practices. Carbon footprint per unit of area(CFa), per unit of maize grain yield(CFy), and per unit of economic output(CFe) were evaluated for three maize cultivation systems: a no mulch system, a conventional plastic mulching system(PM) and a biennial plastic mulching pattern, namely a ’one film for 2 years’ system(PM2), during 2015–2018 in a maize field located on the Loess Plateau of China. The results suggested that PM induced a 24% improvement in maize yields during the four experimental years compared to a no-mulch treatment(NM). However, PM dramatically increased the CFa by 69%, 59% of which was created by the input of the plastic film material, and 10% was created by increases in the soil N2O emissions. The yield improvements from PM could not offset the increases in CFa, and CFy and CFe were both increased by 36%. Shifting from PM to PM2 did not reduce crop yields, but it led to a 21% reduction in CFa and 23% reductions in CFy and CFe due to the reduced input amount of plastic film, decreased soil N2O emissions, and less diesel oil used for tillage. Compared to NM, CFy and CFe were only 5% higher in PM2. This study highlights the necessity of reducing the amount of plastic film input in the development of low-carbon agriculture and shifting from conventional PM cultivation to PM2 could be an efficient option for mitigating GHG emissions while sustaining high crop yields in plastic mulched fields.

Improving maize growth and development simulation by integrating temperature compensatory effect under plastic film mulching into the AquaCrop model

Temperature compensatory effect, which quantifies the increase in cumulative air temperature from soil temperature increase caused by mulching, provides an effective method for incorporating soil temperature into crop models. In this study, compensated temperature was integrated into the AquaCrop model to investigate the capability of the compensatory effect to improve assessment of the promotion of maize growth and development by plastic film mulching(PM). A three-year experiment was conducted from2014 to 2016 with two maize varieties(spring and summer) and two mulching conditions(PM and non-mulching(NM)), and the AquaCrop model was employed to reproduce crop growth and yield responses to changes in NM, PM, and compensated PM. A marked difference in soil temperature between NM and PM was observed before 50 days after sowing(DAS) during three growing seasons. During sowing–emergence and emergence–tasseling, the increase in air temperature was proportional to the compensatory coefficient, with spring maize showing a higher compensatory temperature than summer maize. Simulation results for canopy cover(CC) were generally in good agreement with the measurements, whereas predictions of aboveground biomass and grain yield under PM indicated large underestimates from 60 DAS to the end of maturity. Simulations of spring maize biomass and yield showed general increase based on temperature compensation, accompanied by improvement in modeling accuracy, with RMSEs decreasing from 2.5 to 1.6 t ha^(-1)and from 4.1 t to 3.4 t ha^(-1). Improvement in biomass and yield simulation was less pronounced for summer than for spring maize, implying that crops grown during low-temperature periods would benefit more from the compensatory effect. This study demonstrated the effectiveness of the temperature compensatory effect to improve the performance of the AquaCrop model in simulating maize growth under PM practices.

The EVA plastic film for V-process and steel castings by V-process in China

EVA plastic film is the key material for V-process. Through decades of research, special EVA film for V-process has been produced. The film has adequate elongation; its maximum is about 800% in longitudinal direction and 750% in transversal direction. The single width of the film is 2.8 m and the double width is 5.6 m, which is the widest sheet film for V-process in China. Sheets with different thickness ranging from the thickest 0.35 mm to the thinnest 0.08 mm can meet different demands in China. The film can be used not only for V-process of iron castings, but also for the manganese steel railway frog, steel rocking support and side frame castings for train and the steel bridge box for engine truck.

Practice and Exploration of Scientific Recycling of Agricultural Plastic Film in Nanchong City

Nanchong City is a major grain production city in Sichuan Province.The annual use of agricultural plastic film for grain and oil crop production and the amount of waste agricultural plastic film produced are very large.How to properly recycle agricultural plastic film and reduce the non-point source pollution of agricultural plastic film to agricultural environment has become an unavoidable subject of agricultural production in Nanchong City.In recent years,the scientific recycling of agricultural plastic film in Nanchong City has made great achievement.On the basis of statistical survey,this paper elaborated the main methods and results achieved,analyzed the existing problems,and came up with recommendations for the future work,in the hope of providing a reference for strengthening agricultural plastic film recycling in similar situations.

Characteristics of Mulching Plastic Film Residue in Cotton Fields in the Yellow River Delta

In order to get a clear picture of distribution characteristics of mulching plastic film residue in cotton fields in the Yellow River Delta and make scientific pollution prevention and control strategies, an investigation was conducted in Dongying City. Five typical cotton fields were chosen, and then the number, distri- bution density and area of residual film were measured. The results showed that the residual film was 18. 84-53. 53 kg/hm^2 in cotton fields for more than 20 years, and the differences between fields were larger. The residual density was 225-340 thousand per hectare. There were great differences among residual pieces. The proportion of residual pieces over 25 cm^2 was 94. 1%, that between 100 cm^2 and 500 cm^2 was more than 50. 0%, and that bigger than 500 cm^2 was about 21. 0%. In the Yellow River Delta cotton region, large, thin and difficult to recovery were the main characteristics of mulching plastic film residue, and it had the possibility of mi- grating to deep soil. Thus, the ecological risk of mulching plastic film residue was higher. Key words The Yellow River Delta; Cotton field; Residue of mulching plastic film; Distribution characteristic

Design of New Farm Machine for Chopping Field Straw,Pressing it into Soil and Cleaning up Plastic Film

In this paper,we design a farm machine integrating the functions of chopping field straw,pressing field straw into soil,breaking stubble,and cleaning up plastic film,in order to improve the efficiency of plastic film cleaning,enrich the function of straw chopping equipment,reduce the noise generated at work,and further realize the intelligent harmony. The remote control button is used to control the work of the entire system,and the bluetooth remote control module and matrix keyboard are used to control the vehicle. With STM32 microcontroller as the main control chip,the machine controls the motion of the electric motor by relay,and employs LCD screen to realize real-time display of system work. It is convenient and easy to operate,with good human-computer interaction.

Effects of Plastic Film Mulching on Soil Carbon Fixation Capacity and Fertility Level in Eastern Qinghai

[Objectives]To explore the effects of single application of chemical fertilizers on soil carbon fixation capacity and soil fertility under plastic film mulching conditions in eastern Qinghai,and to provide a theoretical basis for realizing the sustainable development of film mulching planting method in this area.[Methods]The effects of single application of chemical fertilizer cultivation mode under film mulching conditions on the soil organic carbon(SOC),labile organic carbon(LOC),carbon management index(CMI),extractable humus carbon(CHE),humic acid carbon(CHA),and fulvic acid carbon(CFA)in the cultivated layer(0-20 cm)were studied through three consecutive years of field experiments on dryland maize farmland in the eastern Qinghai.[Results]Under the film mulching condition,the SOC,LOC and CMI of the single application of chemical fertilizer cultivation mode were lower than that of the open field control.CHE,CHA and CFA increased with the increase of planting years,but the degree of increase was generally less than that of the open field control.With the increase of planting years,by 2020,the soil LOC/SOC value of film mulching decreased by 4.97%compared with before the start of the experiment,while the open field control increased by 1.11%;the organic carbon oxidation stability coefficient(KOS)of the film mulching was higher than that of the open field control;the soil CHA/CFA value and PQ value were higher than that of the open field control.[Conclusions]Under the condition of single application of chemical fertilizers,the continuous film mulching cultivation mode reduces the soil carbon fixation capacity,and soil organic carbon tends to be stable,which is not conducive to biological utilization and could reduce the soil fertility and degrade the soil quality,causing adverse effects on the stability of crop yield and sustainable production in the long run.

Mulching with plastic film improved the root quality of summersown sweet potato(Ipomoea batatas(L).Lam.)in northern China

The root quality of sweet potato cultivated during the summer season is poor in northern China;thus,this study was conducted to determine whether root quality could be improved through mulching with plastic film(MPF).The effect of MPF on root starch and its composition,the activity of starch synthesis enzymes,and other quality-related parameters were investigated in two purple flesh sweet potato cultivars,Jishu 18 and Ayamurasaki(Aya).The results indicated that root dry matter,anthocyanin content,adenosine triphosphate(ATP),and starch content were higher in both cultivars under the MPF treatment than those under the control treatment.The root adenosine diphosphate glucose pyrophosphorylase/uridine diphosphate glucose pyrophosphorylase(ADPGPPase/UDPGPPase)activity and adenosine triphosphatease(ATPase)activity were increased using MPF.However,under the MPF treatment,the amylose content,soluble sugar content,and granule-bound synthase(GBSS)activity increased in Jishu 18 but decreased in Aya,and the amylopectin content,protein content,and soluble starch synthase(SSS)activity decreased in Jishu 18 but increased in Aya.Therefore,MPF seems benifit to improve the quality of sweet potato,but the effects of this treatment condition may be dependent on the cultivar.

Cotton's Water Demand and Water-Saving Benefits under Drip Irrigation with Plastic Film Mulch

The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.

Structural and Thermomechanical Study of Plastic Films Made from Cassava-Starch Reinforced with Kaolin and Metakaolin

The structural and thermomechanical properties of starch-based plastic films reinforced with kaolin and metakaolin have been studied by various techniques (X-ray diffraction, IR-TF spectroscopy, scanning electron microscopy, tensile tests, and thermal resistance). The results obtained showed that kaolin, an inert material, prevents the starch from losing its granular structure and to solubilize during the heating, generating plastic films of low Young’s modulus (7 MPa). On the other hand, metakaolin, an amorphous and dehydroxylated material obtained after heating of kaolin at 700°C for 1 hour, substantially improves the thermomechanical properties of the plastic films. The Young’s modulus increases from 19 MPa to 25 MPa while the thermal resistance increases from 90°C to 120°C. This was attributed to good dispersion of the metakaolin in the polymer matrix after the loss of the granular structure of the starch during heating.

Research on Tearing Property of Reinforced Plastic Film with Bi-axial Warp Knitted Fabric Skeleton

The specification of laid-in and warp yams,thedensity of fabric and the specification of groundyam are of great importance when the bi-axialwarp knitted fabric being knitted.In this paper,the tearing property of the reinforced plastic filmwith bi-axial warp knitted fabric skeleton istested and analyzed.The resuits show thatamong the three factors,the specification of laid-in and warp yam has the greatest influence onthe tearing strength of the reinforced plastic film,while the rest of them has secondary and lesseffect respectively,and there is exponential re-lation between the tearing strength of the rein-forced plastic film and the number of yams in thedirection of force.

Agronomic performances of biodegradable and non-biodegradable plastic film mulching on a maize cropping system in the semi-arid Loess Plateau,China

Biodegradable plastic film mulch (PFM) is considered an alternative to non-biodegradable PFM to mitigate the negative impacts of residual film.However,the agronomic performance of biodegradable PFM in comparison to non-biodegradable PFM still needs to be tested.In this study,we evaluated the effects of biodegradable and non-biodegradable PFM on soil physicochemical properties,microbial community,and enzyme activities,as well as maize growth performance.Biodegradable and non-biodegradable PFM both increased soil temperature,water content,N content,and microbial biomass and maize yield by up to 30%,but decreased soil enzyme activities as compared to no mulching (control,CK).Most soil physicochemical properties,microbial community,and enzyme activities were similar under non-biodegradable and biodegradable PFM at the early stages of maize growth.However,at the late stages,soil temperature,water content,mineral N,NO_(3)^(-)-N,ammonia monooxygenase (AMO) activity,and total phospholipid fatty acids (PLFAs) decreased under biodegradable PFM owing to film fragmentation.White PFM increased soil temperature,water content,and total PLFAs at the early stages of maize growth but decreased soil mineral N and total PLFAs at the late stages,as compared to black PFM.As soil temperature and N availability were the major factors affecting soil microbial community,microbial activity decreased after the fragmentation of biodegradable PFM,owing to the decreased soil temperature,water content,and mineral N.Notably,biodegradable PFM could decrease NO_(3)^(-)-N accumulation in topsoil by decreasing N transformation due to the lower microbial and N-related enzyme (e.g.,AMO) activities,compared with non-biodegradable PFM,which may avoid negative environmental impacts,such as NO_(3)^(-)-N leaching or gas emission after harvest.Maize yield,height,aboveground biomass,and N uptake under biodegradable PFM were similar to those under non-biodegradable PFM during maize growth,implying that biodegradable PFM has no negative impact on crop growth and yield.In general,biodegradable PFM was equivalent to non-biodegradable PFM in terms of maize yield increase and N uptake,but was environmentally friendly.Therefore,biodegradable PFM can be used as an alternative to non-biodegradable PFM in semi-arid areas for sustainable agricultural practices.