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...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.展开更多
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 o...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.展开更多
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.) fiel...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.展开更多
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 ...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.展开更多
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 larg...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.展开更多
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 ...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.展开更多
[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 theoretic...[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.展开更多
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 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.展开更多
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 ...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.展开更多
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 Fi...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%.展开更多
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 no...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.展开更多
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 micr...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.展开更多
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 r...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.展开更多
Plastic film mulching has been widely used to increase maize yield in the semiarid area of China.However, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains cont...Plastic film mulching has been widely used to increase maize yield in the semiarid area of China.However, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains controversial.A field experiment was initiated in 2013 with five different film mulching methods:(i) control method, flat planting without mulching (CK),(ii) flat planting with half film mulching (P),(iii) film mulching on ridges and planting in narrow furrows(S),(iv) full film mulching on double ridges (D), and (v) film mulching on ridges and planting in wide furrows (R).The effects on soil organic carbon (SOC) content, storage, and fractions, and on the carbon management index (CMI)were evaluated after nine consecutive years of plastic film mulching.The results showed that long-term plastic film mulching generally maintained the initial SOC level.Compared with no mulching, plastic film mulching increased the average crop yield, biomass yield, and root biomass by 48.38, 35.06, and 37.32%, respectively, which led to the improvement of SOC sequestration.Specifically, plastic film mulching significantly improved CMI, and increased the SOC content by 13.59%, SOC storage by 7.47%and easily oxidizable organic carbon (EOC) by 13.78%on average,but it reduced the other labile fractions.SOC sequestration and CMI were improved by refining the plastic film mulching methods.The S treatment had the best effect among the four mulching methods, so it can be used as a reasonable film mulching method for sustainable agricultural development in the semiarid area.展开更多
Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,China.However,there is no specific quantitative basis for RPF pollution or a clea...Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,China.However,there is no specific quantitative basis for RPF pollution or a clear understanding of the influence of residual film on crop growth.The aim of this study was to investigate the effect of RPF on the growth of cotton,an important cash crop of Xinjiang.Based on the field conditions and previous reports,various amount of residual film was applied in 0-30 cm soil layer.The growth index including emergence rate,dry matter,and yield of cotton was examined at different growth stages under different soil residual film levels.Results demonstrated a significant effect of RPF on soil moisture distribution and movement.Plastic residues had a significant effect on cotton growth at levels above 200 kg/hm2,and the yield decreased as the RPF amount increased.Based on these findings,200 kg/hm2 was suggested as a threshold level to determine the effects of RPF on cotton.This study provided a basis to rate RPF pollution in farmland soils and help understand the impact of pollution on crop productivity.展开更多
In order to achieve the construction standard of high mechanized performance of the seedbed with whole plastic-film mulching on double ridges,in this study,the forms of suppression failure were analyzed,and the key fa...In order to achieve the construction standard of high mechanized performance of the seedbed with whole plastic-film mulching on double ridges,in this study,the forms of suppression failure were analyzed,and the key factors influencing the suppression performance were determined based on the structure of the seedbed suppression device and its working principles.The discrete element method was adopted for numerical simulation on the suppression process of the seedbed with whole plastic film mulching on double ridges;the parameters during the interaction between the suppression device and seedbed soil were extracted and analyzed,such as contact area,sinkage and horizontal traction resistance trend of press wheels on big ridges and furrows of small ridge.Taking the suppression load on big ridges,suppression load on furrows of small ridge,and advancing velocity of the combined operation machine as the independent variables,qualified rate of suppression as the response value,a mathematical model between the test factors and qualified rate of suppression was established,to explore the influence sequence of the factors on suppression qualified rate.The optimal working parameters of the suppression device were finally obtained:the suppression load on big ridges was 40 N,suppression load on furrows of small ridge was 69.8 N and the machine advancing velocity was 0.98 m/s,and the achieved mean value of suppression qualified rate was 92.6%.Field verification test showed that the mean value of suppression qualified rate was 90.3%,a mere difference of 2.3%compared with the simulation result.The actual operation of the sample machine was basically consistent with the simulation process and could reveal the mechanized suppression operation mechanism of the seedbed with whole plastic film mulching on double ridges,indicating that the established DEM model and its parameter setting were relatively accurate and reasonable.展开更多
In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed,and to meet its forming process and corresponding agronomic requirements of the mechanized dou...In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed,and to meet its forming process and corresponding agronomic requirements of the mechanized double ridge seedbed,the key working parameters such as the speed of rotary blade group,the thickness of upturned sod and the power consumption of rotary blade group under different parameters were analyzed based on related working performance in ridge forming.Also,the test factors and their range of values were finally determined in this study.Discrete element method(DEM)simulation was applied in the numerical simulation of the mechanized ridge forming process of whole plastic mulched double ridges,and the ridge forming effect and digging resistance variation characteristics of different types of shovels were compared.Taking the forward speed of the combined machine,the penetration angle of the arc-shaped shovel and the depth of rotary tillage as independent variables,and the qualified rate of seedbed tillage as the response value,the mathematical model between the test factors and the qualified rate of the seedbed tillage was established,to explore the influence sequence of the factors on the qualified rate of seedbed tillage,and obtained the following optimal working parameters of the ridge forming device:the advancing velocity of the combined machine of 0.50 m/s,penetration angle of the arc-shaped shovel of 31°,rotary tillage depth of 140 mm,and average qualified rate 95.20%of seedbed tillage in corresponding simulation verification test.Field test showed that the average qualified rate of seedbed tillage in ridge forming device was 93.60%,which was close to that of the simulation results.The actual working condition of the sample machine was basically in line with the simulation process and could relatively precisely reflect the mechanized ridge forming mechanism of whole plastic double ridges.The results showed that the established DEM model and its parameter setting were relatively accurate and reasonable.展开更多
Plastic film is an important resource in agricultural production,but it takes hundreds of years to degrade completely in natural environment.The large-scale use of plastic film will inevitably lead to serious environm...Plastic film is an important resource in agricultural production,but it takes hundreds of years to degrade completely in natural environment.The large-scale use of plastic film will inevitably lead to serious environmental pollution.One way to solve the problem is to develop a substitutable mulching film,such as a biodegradable film that can ultimately be decomposed to water,carbon dioxide,and soil organic matter by micro-organisms.In this study,a 2-year experiment was conducted to determine the degradation properties of a biodegradable plastic film,including degradation rate,surface microstructure,tensile strength and elongation at break,and the effects of different mulching treatments on soil temperature and maize yield.The mulching experiment was conducted with three different biodegradable plastic films with different degradation rates,using a common plastic film and a non-mulched treatment as control.With the addition of the additives for degradation in the biodegradable plastic films,the degradation rates increased significantly,which were 7.2%-17.8%in 2017 and 18.1%-35.2%in 2018 after maize harvesting.However,the degradation occurred mainly on the ridge side.The decrease in tensile strength and elongation was proportional to the degradation rate of the degradable film.The SEM results indicated that the surface microstructures of the biodegradable films were loose and heterogeneous after maize harvesting.Biodegradable plastic film mulching increased the soil temperature at soil depths of 5 cm,15 cm,and 25 cm,over the maize’s entire growth period,by 3.1℃-3.2℃ in 2017 and 1.2℃-2.1℃ in 2018 compared with the non-mulched treatment.The biodegradable plastic film increased the maize yield by 10.4%-14.3%in 2017 and 11.6%-24.7%in 2018.The soil temperature and maize yield increases were statistically significant;however,with respect to maize qualities,there were no statistically significant increases among the five treatments.This study shows that biodegradable plastic film can be used as a substitute for common plastic film.However,the ingredients in biodegradable plastic films should be improved further to ensure that they can be degraded completely after crop harvest.展开更多
Plastic film mulch systems are used widely in arid areas, and the associated tillage measures affect soil properties, root and crop growth, and nutrient uptake. However, much debate surrounds the most suitable tillage...Plastic film mulch systems are used widely in arid areas, and the associated tillage measures affect soil properties, root and crop growth, and nutrient uptake. However, much debate surrounds the most suitable tillage method for plastic film mulch systems. We conducted a two-year field experiment to explore the impact of three tillage treatments-rotary tillage before ridge–furrow plastic film mulch(MR), no-tillage before ridge–furrow plastic film mulch(MZ), and plow tillage before ridge–furrow plastic film mulch(MP)-on soil total nitrogen, available nitrogen, root stratification structure,nitrogen transfer and utilization, and maize yield. The results showed that MP had better soil quality than either MR or MZ over 2019 and 2020, with higher nitrate-nitrogen and total nitrogen in the 0–40 cm soil layer. MP improved the soil physicochemical properties more than the other treatments, producing significantly higher root numbers and root biomass for the aerial and underground nodal roots than MR and MZ. At harvest, MP had the highest root biomass density,root length density, and root surface area density in the different soil layers(0–20, 20–40, and 0–40 cm). Significant correlations occurred between root biomass and aboveground nitrogen accumulation during maize growth. During grain filling, MP had the greatest nitrogen transfer amount, significantly increasing root and aboveground nitrogen transfer by 19.63–45.82% and 11.15–24.56%, respectively, relative to the other treatments. MP significantly produced 1.36–26.73%higher grain yields and a higher grain crude protein content at harvest than MR and MZ. MP also had higher values for the nitrogen harvest index, nitrogen uptake efficiency, and partial factor productivity of nitrogen fertilizer than MR and MZ.In conclusion, plow tillage combined with a ridge–furrow plastic film mulch system facilitated maize root development and improved nitrogen utilization, thereby increasing maize yield more than the other treatments.展开更多
Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine...Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11:00 and 13:00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13:00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.展开更多
基金supported by the National Natural Science Foundation of China (51909228 and 52209071)the “High-level Talents Support Program” of Yangzhou University+2 种基金“Chunhui Plan” Cooperative Scientific Research Project of Ministry of Education of China (HZKY20220115)the China Postdoctoral Science Foundation (2020M671623)the “Blue Project” of Yangzhou University。
文摘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.
基金We thank the financial support from the National Natural Science Foundation of China
文摘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.
基金financially supported by the National Natural Science Foundation of China(31270553,51279197,41401343)the Special Fund for Agricultural Profession, China(201103003)
文摘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.
基金supported by the National Natural Science Foundation of China (31901477, 31871575 and 3191101554)the Central Public Interest Scientific Institution Basal Research FundInstitute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences (BSRF201909)。
文摘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.
文摘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.
基金Supported by Key Major Production Accident Prevention and Control Technology Project of State Administration of Work Safety in 2015(shandong-0075-2015AQ)
文摘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.
基金Project of Natural Science Foundation of Qinghai Province(2018-ZJ-724)Major Science and Technology Program of Qinghai Province(2019-NK-A11).
文摘[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.
基金supported by the Natural Science Foundation of Shandong Province,China(ZR2014YL015)the Agricultural Seed of Shandong Province,China(2016LZGC005)+1 种基金the earmarked fund for China Agriculture Research System(CARS-10-B7 and CARS-10-B8)the Youth Foundation of Shandong Academy of Agricultural Sciences,China(2014QNM31)
文摘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.
文摘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.
基金Supported by 973 Project(2009CB421302)Innovation Project of Chinese Academy of Sciences(KZCX2-YW-127)Youth Science Foundation of China(41401025)
文摘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%.
基金funded by the National Natural Science Foundation of China(No.41877086)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2020JZ-16)+1 种基金the UK Global Research Challenges Fundthe UK Natural Environment Research Council Project(No.NE/V005871/1)。
文摘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.
文摘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.
文摘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.
基金This research was supported by the National Key Research and Development Program of China(2021YFE0101302and2021YFD1901102)the National Natural Science Foundation of China(31801314 and 31901475)。
文摘Plastic film mulching has been widely used to increase maize yield in the semiarid area of China.However, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains controversial.A field experiment was initiated in 2013 with five different film mulching methods:(i) control method, flat planting without mulching (CK),(ii) flat planting with half film mulching (P),(iii) film mulching on ridges and planting in narrow furrows(S),(iv) full film mulching on double ridges (D), and (v) film mulching on ridges and planting in wide furrows (R).The effects on soil organic carbon (SOC) content, storage, and fractions, and on the carbon management index (CMI)were evaluated after nine consecutive years of plastic film mulching.The results showed that long-term plastic film mulching generally maintained the initial SOC level.Compared with no mulching, plastic film mulching increased the average crop yield, biomass yield, and root biomass by 48.38, 35.06, and 37.32%, respectively, which led to the improvement of SOC sequestration.Specifically, plastic film mulching significantly improved CMI, and increased the SOC content by 13.59%, SOC storage by 7.47%and easily oxidizable organic carbon (EOC) by 13.78%on average,but it reduced the other labile fractions.SOC sequestration and CMI were improved by refining the plastic film mulching methods.The S treatment had the best effect among the four mulching methods, so it can be used as a reasonable film mulching method for sustainable agricultural development in the semiarid area.
基金This work was financially supported by National key R&D plan of China(No.2017YFD0701102)the Corps key R&D projects(No.2019AB007)+2 种基金the Special Fund for Agroscientific Research in the Public Interest(No.201503105)and the National Natural Science Foundation of China(Grant No.11562019)The authors are grateful to the farmers of the trial area for their cooperation.
文摘Long-term and widespread use of plastic mulching has led to the accumulation of residual plastic film(RPF)in farmland soils of Xinjiang,China.However,there is no specific quantitative basis for RPF pollution or a clear understanding of the influence of residual film on crop growth.The aim of this study was to investigate the effect of RPF on the growth of cotton,an important cash crop of Xinjiang.Based on the field conditions and previous reports,various amount of residual film was applied in 0-30 cm soil layer.The growth index including emergence rate,dry matter,and yield of cotton was examined at different growth stages under different soil residual film levels.Results demonstrated a significant effect of RPF on soil moisture distribution and movement.Plastic residues had a significant effect on cotton growth at levels above 200 kg/hm2,and the yield decreased as the RPF amount increased.Based on these findings,200 kg/hm2 was suggested as a threshold level to determine the effects of RPF on cotton.This study provided a basis to rate RPF pollution in farmland soils and help understand the impact of pollution on crop productivity.
基金The authors acknowledge that this work was financially supported by the National Natural Science Foundation of China(Grant No.51775115,No.52065005)Outstanding Youth Foundation of Gansu Province(Grant No.20JR10RA560)+1 种基金Natural Science Foundation of Gansu Province(Grant No.20JR5RA029)Research Program Sponsored by Gansu Provincial Key Laboratory of Aridland Crop Science,Gansu Agricultural University(Grant No.GSCS-2020-01).
文摘In order to achieve the construction standard of high mechanized performance of the seedbed with whole plastic-film mulching on double ridges,in this study,the forms of suppression failure were analyzed,and the key factors influencing the suppression performance were determined based on the structure of the seedbed suppression device and its working principles.The discrete element method was adopted for numerical simulation on the suppression process of the seedbed with whole plastic film mulching on double ridges;the parameters during the interaction between the suppression device and seedbed soil were extracted and analyzed,such as contact area,sinkage and horizontal traction resistance trend of press wheels on big ridges and furrows of small ridge.Taking the suppression load on big ridges,suppression load on furrows of small ridge,and advancing velocity of the combined operation machine as the independent variables,qualified rate of suppression as the response value,a mathematical model between the test factors and qualified rate of suppression was established,to explore the influence sequence of the factors on suppression qualified rate.The optimal working parameters of the suppression device were finally obtained:the suppression load on big ridges was 40 N,suppression load on furrows of small ridge was 69.8 N and the machine advancing velocity was 0.98 m/s,and the achieved mean value of suppression qualified rate was 92.6%.Field verification test showed that the mean value of suppression qualified rate was 90.3%,a mere difference of 2.3%compared with the simulation result.The actual operation of the sample machine was basically consistent with the simulation process and could reveal the mechanized suppression operation mechanism of the seedbed with whole plastic film mulching on double ridges,indicating that the established DEM model and its parameter setting were relatively accurate and reasonable.
基金The authors acknowledge that this work was financially supported by the Research Program Sponsored by Gansu Provincial Key Laboratory of Aridland Crop Science,Gansu Agricultural University(No.GSCS-2020-01)National Natural Science Foundation of China(Grant No.51775115,No.52065005,No.51405086)+1 种基金Fuxi Young Talents Fund of Gansu Agricultural University(Gaufx-03Y01)China Agriculture Research System(CARS-14-1-28).
文摘In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed,and to meet its forming process and corresponding agronomic requirements of the mechanized double ridge seedbed,the key working parameters such as the speed of rotary blade group,the thickness of upturned sod and the power consumption of rotary blade group under different parameters were analyzed based on related working performance in ridge forming.Also,the test factors and their range of values were finally determined in this study.Discrete element method(DEM)simulation was applied in the numerical simulation of the mechanized ridge forming process of whole plastic mulched double ridges,and the ridge forming effect and digging resistance variation characteristics of different types of shovels were compared.Taking the forward speed of the combined machine,the penetration angle of the arc-shaped shovel and the depth of rotary tillage as independent variables,and the qualified rate of seedbed tillage as the response value,the mathematical model between the test factors and the qualified rate of the seedbed tillage was established,to explore the influence sequence of the factors on the qualified rate of seedbed tillage,and obtained the following optimal working parameters of the ridge forming device:the advancing velocity of the combined machine of 0.50 m/s,penetration angle of the arc-shaped shovel of 31°,rotary tillage depth of 140 mm,and average qualified rate 95.20%of seedbed tillage in corresponding simulation verification test.Field test showed that the average qualified rate of seedbed tillage in ridge forming device was 93.60%,which was close to that of the simulation results.The actual working condition of the sample machine was basically in line with the simulation process and could relatively precisely reflect the mechanized ridge forming mechanism of whole plastic double ridges.The results showed that the established DEM model and its parameter setting were relatively accurate and reasonable.
基金This research was financially supported by the Province Natural Science Foundation of Liaoning(20180550617)the Special Program for National Key Research and Development Project of China(2018YFD0300301)the Special Fund for Agro-scientific Research in the Public Interest of China(201503105&201303125).
文摘Plastic film is an important resource in agricultural production,but it takes hundreds of years to degrade completely in natural environment.The large-scale use of plastic film will inevitably lead to serious environmental pollution.One way to solve the problem is to develop a substitutable mulching film,such as a biodegradable film that can ultimately be decomposed to water,carbon dioxide,and soil organic matter by micro-organisms.In this study,a 2-year experiment was conducted to determine the degradation properties of a biodegradable plastic film,including degradation rate,surface microstructure,tensile strength and elongation at break,and the effects of different mulching treatments on soil temperature and maize yield.The mulching experiment was conducted with three different biodegradable plastic films with different degradation rates,using a common plastic film and a non-mulched treatment as control.With the addition of the additives for degradation in the biodegradable plastic films,the degradation rates increased significantly,which were 7.2%-17.8%in 2017 and 18.1%-35.2%in 2018 after maize harvesting.However,the degradation occurred mainly on the ridge side.The decrease in tensile strength and elongation was proportional to the degradation rate of the degradable film.The SEM results indicated that the surface microstructures of the biodegradable films were loose and heterogeneous after maize harvesting.Biodegradable plastic film mulching increased the soil temperature at soil depths of 5 cm,15 cm,and 25 cm,over the maize’s entire growth period,by 3.1℃-3.2℃ in 2017 and 1.2℃-2.1℃ in 2018 compared with the non-mulched treatment.The biodegradable plastic film increased the maize yield by 10.4%-14.3%in 2017 and 11.6%-24.7%in 2018.The soil temperature and maize yield increases were statistically significant;however,with respect to maize qualities,there were no statistically significant increases among the five treatments.This study shows that biodegradable plastic film can be used as a substitute for common plastic film.However,the ingredients in biodegradable plastic films should be improved further to ensure that they can be degraded completely after crop harvest.
基金provided by the National Natural Science Foundation of China (31701384 and 32071980)。
文摘Plastic film mulch systems are used widely in arid areas, and the associated tillage measures affect soil properties, root and crop growth, and nutrient uptake. However, much debate surrounds the most suitable tillage method for plastic film mulch systems. We conducted a two-year field experiment to explore the impact of three tillage treatments-rotary tillage before ridge–furrow plastic film mulch(MR), no-tillage before ridge–furrow plastic film mulch(MZ), and plow tillage before ridge–furrow plastic film mulch(MP)-on soil total nitrogen, available nitrogen, root stratification structure,nitrogen transfer and utilization, and maize yield. The results showed that MP had better soil quality than either MR or MZ over 2019 and 2020, with higher nitrate-nitrogen and total nitrogen in the 0–40 cm soil layer. MP improved the soil physicochemical properties more than the other treatments, producing significantly higher root numbers and root biomass for the aerial and underground nodal roots than MR and MZ. At harvest, MP had the highest root biomass density,root length density, and root surface area density in the different soil layers(0–20, 20–40, and 0–40 cm). Significant correlations occurred between root biomass and aboveground nitrogen accumulation during maize growth. During grain filling, MP had the greatest nitrogen transfer amount, significantly increasing root and aboveground nitrogen transfer by 19.63–45.82% and 11.15–24.56%, respectively, relative to the other treatments. MP significantly produced 1.36–26.73%higher grain yields and a higher grain crude protein content at harvest than MR and MZ. MP also had higher values for the nitrogen harvest index, nitrogen uptake efficiency, and partial factor productivity of nitrogen fertilizer than MR and MZ.In conclusion, plow tillage combined with a ridge–furrow plastic film mulch system facilitated maize root development and improved nitrogen utilization, thereby increasing maize yield more than the other treatments.
基金supported by the Science and Technology Foundation of Guizhou Province,China (20146015-2,20152099 and 20161097)the Special Fund for Excellent Young Talents of Guizhou Province,China (201534)the Foundation of Guizhou Academy of Tobacco Science,China (GZYKS2018-02)
文摘Solving high-temperature plastic mulching film-induced leaf burning in the first week during tobacco cultivation would take much time and effort. In the present study, the growth as well as the leaf sugar and nicotine contents of seedlings with or without leaf burning induced by high-temperature plastic mulching film were tested at two independent sites in 2015 and 2016 to identify the influence of leaf burning on seedling growth. The results showed that the growth of seedlings with leaf burning was improved with increased leaf area, leaf number and plant height compared to those without leaf burning, combined with an increased seedling survival rate at two sites in two years. In seedlings with leaf burning, the contents of fructose and glucose increased and peaked at 11:00 and 13:00 in the leaf and root, respectively, with an increased root nicotine content beginning at 13:00, highlighting the signalling role of sugars. Activities of antioxidant enzymes including peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) were all increased in seedlings with leaf burning. More plant biomass was allocated to roots in seedlings with leaf burning with increased root volume compared to control seedlings, which might facilitate the absorption of water and nutrients from the soil. Our findings demonstrate that high-temperature plastic mulching film-induced leaf burning not inhibited but benefited seedling survival and growth, suggesting that the time and labour-consuming manual plucking of burnt leaves can be avoided during tobacco cultivation.