The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number

Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance analysis.The results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,respectively.The average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) treatment.There were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically signifiant.Soil water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,respectively.The relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in CK.In terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three treatments.Based on the three analysis methods,we found that spike number and ET were positively correlated with grain yield.However,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in CK.Suifcient SWSSF could indirectly increase spike number and ET in the three treatments.Based on these results,mulch can improve yield and soil water storage.The most important factor affecting the grain yield of dryland wheat was spike number under mulching,and ET with CK.These findings may help us to understand the main factors influencing dryland wheat grain yield under mulching conditions compared to CK.

Can soil organic carbon sequestration and the carbon management index be improved by changing the film mulching methods in the semiarid region?

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.

Rice Cultivation under Film Mulching Can Improve Soil Environment and Be Beneficial for Rice Production in China

Rice cultivation under film mulching is an integrated management technology that can conserve water, increase soil temperature, improve yield, and enhance water and nitrogen use efficiencies. Despite these advantages, the system does have its drawbacks, such as soil organic matter reduction and microplastic pollution, which impede the widespread adoption of film mulching cultivation in China. Nonetheless, the advent of degradable film, controlled-release fertilizer, organic fertilizer, and film mulching machinery is promoting the development of rice film mulching cultivation. This review outlines the impact of rice cultivation under film mulching on soil moisture, soil temperature, soil fertility, greenhouse gas emissions, weed control, and disease and pest management. It also elucidates the mechanism of changes in rice growth, yield and quality, water use efficiency, and nitrogen use efficiency. This paper incorporates a review of published research articles and discusses some uncertainties and shortcomings associated with rice cultivation under film mulching. Consequently, prospective research directions for the technology of rice film mulching cultivation are outlined, and recommendations for future research into rice cultivation under film mulching are proposed.

Effect of Different Mulching Materials on Growth Parameters and Yield of Okra (Abelmoschus esculentus) Production in Minna, Nigeria

During the 2022 growing season (August to November) at the Federal University of Technology, Minna School farm, Niger State, an experiment was conducted to investigate the influence of mulching on Okras growth, yield, and moisture content was examined across four distinct growth stages (initial, development, mid, and late) and at varying soil depths (0 - 30 cm and 30 - 60 cm). The study employed a randomised complete block design with four replications, encompassing control (T0), groundnut shells mulch (T1), black polythene mulch (T2), and white polythene mulch (T3) as treatments. The highest average Okra fresh pod yield, amounting to 23.4 t/ha, was achieved by implementing white plastic mulch, contrasting with the control treatment, which yielded the lowest at 22 t/ha. Notably, the control plots exhibited yield reductions of up to 32% compared to the plots employing white plastic mulching. The utilisation of mulch had a notable impact on the overall crop yield, with the superior quality evident in the treatment employing white plastic mulch (26 t/ha). The control treatment exhibited the lowest quality at 24.3 t/ha. Groundnut shell mulch influenced moisture conservation, but no significant variance was observed compared to the control plots. Therefore, the study suggests that polythene mulch may be the most suitable type to enhance the quality of okra production by conserving soil moisture. Among the biodegradable and non-biodegradable mulches used in this study, white polythene mulch was the most effective.

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.

Mulching broad ridges with a woven polypropylene fabric increases the growth and yield of young pear trees ‘Yuluxiang' in the North China Plain

Unlike traditional ridging, mulching broad ridges with a woven polypropylene fabric (WPF) can reduce soil evaporation during the drought season and avoid long saturation time in the root zone of pear trees during the rainy season. In this study, field experiments were conducted from 2017 to 2020 in a pear orchard in the North China Plain to investigate the effects of mulching broad ridges (0.3 m in height and 2 m in width) with WPF on soil temperature and moisture, nitrogen leaching, vegetative and reproductive growth of young pear trees(Pyrus bretschneideri Rehd.‘Yuluxiang’). The experiments involved two treatments, namely, control (traditional no-ridge planting without mulching) and mulching broad ridges with WPF (RM treatment). The results showed that the RM treatment increased soil moisture and temperature and decreased nitrogen leaching, resulting in vigorous growth of the young pear trees. Moreover, the RM treatment increased the tree trunk cross-sectional area and height of the young pear trees by 37%and 8%in 2020, respectively. The nitrate nitrogen content at the soil layer depth of 0-30 cm was significantly higher in the RM than that in control. Furthermore, the RM treatment significantly increased the fruit yield due to larger tree size. In addition, compared with control, significantly higher fruit soluble solid content of RM treatment was detected in 2020. High precipitation (423 mm) occurred during fruit enlargement stage in 2020, RM treatment decreased the rainfall infiltration in the ridge and the soil moisture in root region, resulting in the improvement of fruit quality, compared with control.Therefore, mulching broad ridges with WPF can be implemented to increase soil moisture during drought season, soil temperature, and nitrate nitrogen content, thereby improving the growth and fruit yield of young pear trees. Additionally, it can reduce soil moisture in the root zone during the rainy season and improve the fruit quality of the trees. Finally, it can reduce nitrate nitrogen leaching, thereby reducing environmental pollution.

Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat

In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.

Plastic mulch increases dryland wheat yield and water-use productivity,while straw mulch increases soil water storage

Amplifying drought stress and high precipitation variability impair dryland wheat production.These problems can potentially be minimized by using plastic mulch(PM)or straw mulch(SM).Therefore,wheat grain yield,soil water storage,soil temperature and water-use productivity of PM and SM treatments were compared with no mulch(CK)treatment on dryland wheat over a period of eight seasons.Compared to the CK treatment,PM and SM treatments on average significantly increased grain yield by 12.6 and 10.5%,respectively.Compared to the CK treatment,SM treatment significantly decreased soil daily temperature by 0.57,0.60 and 0.48℃ for the whole seasons,growing periods and summer fallow periods,respectively.In contrast,compared to the CK treatment,PM treatment increased soil daily temperature by 0.44,0.51 and 0.27℃ for the whole seasons,growing periods and summer fallow periods,respectively.Lower soil temperature under SM allowed greater soil water storage than under PM.Soil water storage pre-seeding was 17%greater under the SM than under the PM treatment.Soil water storage post-harvest was similar for the PM and SM treatments,but evapotranspiration was 4.5%higher in the SM than in the PM treatment.Consequently,water-use productivity was 6.6%greater under PM than under the SM treatment.Therefore,PM treatment increased dryland wheat yield and water-use productivity,while straw mulch increased soil water storage.

Effect of Different Mulch Materials on Yield and Nutrition Profile of Common Capsicum (Capsicum annuum) Cultivars in Bangladesh

Capsicum is a nutritious vegetable and its cultivation in farms is getting popular in Bangladesh. Although many efforts have lain to explore better yielding and nutritionally rich cultivars with suitable modern cultivation techniques but still have to find the desired outcome. Thus, it’s necessary to conduct further research to identify the high-yielding and nutritious capsicum cultivars in Bangladesh. An experiment was conducted from July 2021 to June 2022 at the Bangladesh Institute of Research and Training on Applied Nutrition (BIRTAN) research field with three cultivars of capsicum: B0 = California Wonder, B1 = BARI Misti Morich-1 and B2 = BARI Misti Morich-2 and three mulching: T0 = No mulching, T1 = Water hyacinth, T2 = Poly Mulching in randomized complete block design with three replications to identify better quality capsicum cultivar and suitable mulching material. Among cultivars the BARI Misti Morich-2 (B2) showed increased agronomic parameters like number of branches and effective branches per plant, leaves length and width, consequently yield and yield contributing traits were also enhanced like fruits per plant, fruit length, fruit diameter and yield per plant (25.97%, 4.54%, 3.64% and 21.43%, respectively). Poly Mulching (T2) increased agronomic traits, yield traits and yield (0.61 kg) than BARI Misti Morich-1 (T1). The combined effect of B2T2 increased the number of branches per plant, effective branches per plant, leaves length and breadth by 40%, 90%, 15.57% and 26.22%, respectively, hence resulting in an increased yield of 20%. BARI Misti Morich-2 cultivar showed an increase in Fe, Zn and Vitamin-C content of 26.24% and 23.10%, 8.82% and 5.14%, and 6.03% and 5.74% than B0 and B1 cultivars, respectively. Therefore, BARI Misti Morich-2 exhibited the improved agronomic, yield and nutritional traits of capsicum under poly mulching among other cultivars in Bangladesh.

Effects of Film Mulching on the Growth of Silage Maize and Weed

[Objective] The aim was to provide scientific reference for the production of silage maize in correlated regions of Tibet.[Method] Effects of film mulching on the growth period,growth traits and yield of silage maize and weed were analyzed.[Result] Under the treatment of film mulching,the growth period of silage maize could be advanced for 7-16 d; the plant length,stem diameter and leaf area were increased; and the grain output was increased by 75.9%.According to the market price of silage maize in 2008,22 500 Yuan/hm^2 was increased.There were 13 kinds of weeds in silage maize field,which belonged to 13 genera,8 families.Among them,6 kinds of weeds belonged to Gramineae,among which Echinochloa crusgalli and Setaria viridis were dominated in the weed communities.Plantago depressa,Eragrostis pilosa and Malva verticillata var.chinensis could be totally controlled by the film mulching; meanwhile the others could be also controlled in a certain degree except Echinochloa crusgalli.[Conclusion] The plastic mulching planting is worth popularizing for the developing of animal husbandry and the incoming of the local farmers in Tibet.

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 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 Tillage and Mulching Modes on Tobacco Output Value and Soil Quality

Based on three years of long-term fixed-site field trial, the effects of differ- ent tillage and mulching modes on the yield and output value of tobacco and soil quality were investigated. The results showed that the yield and output value of to- bacco in tillage treatment were improved by 22.72 % and 37.23 % compared with non-tillage treatment, respectively; the yield and output value of tobacco in rotation treatment were improved by 1.83% and 19.41% compared with continuous cropping treatment, respectively; the yield and output value of tobacco in straw mulching treatment were improved by 3.55% and 2.4% compared with non-straw mulching treatment, respectively, which indicated that tillage, rotation and straw mulching could improve the yield and output value of tobacco to a certain extent; especially, the yield and output value of tobacco increased significantly after plowing under rotation conditions. The contents of available phosphorus （AP）, alkali-hydrolyzable nitrogen （AN）, organic matter （OM）, total nitrogen （TN） and total phosphorus （TP） in non- tillage treatment were 35.14%, 9.92%, 9.57%, 4.40% and 34.16% higher compared with tillage treatment; especially, under non-tillage conditions, soil pH and contents of available potassium （AK）, AP, AN,OM,TN,TP and total potassium （TK） in continu- ous cropping field were 2.01%, 48.68%, 73.09%, 11.45%, 7.71%, 7.31%, 47.68% and 11.78% higher compared with rotation field, indicating that non-tillage treatment and continuous cropping could improve the total content and available content of organic matter, nitrogen and phosphorus. Therefore, from the perspective of soil fer- tility improvement and sustainable tobacco production, continuous cropping under non-tillage conditions might be the most appropriate cropping pattern for local soil fertility improvement; aiming at improving the yield and output value of tobacco, green manure-tobacco→, green manure/wheat/maize→green manure-tobacco ro- tation might be the most appropriate cropping pattern.

Effects of Different Mulching Methods on Primary Substances and Secondary Substances of Lycium barbarum L.

[Objective] The aim was to provide certain theoretical basis for stuides on the high yield and high quality cultivation of Lycium barbarum L..[Method] Under yield conditions,the accumulation of primary substances and secondary substances of Lycium barbarum L.was studied under different mulching treatments.[Result] Different mulching methods all had a certain effects on the contents of main primary substances and main secondary substances in Lycium barbarum L.fruit.Among them,carbohydrates and flavonoids contents in Lycium barbarum L.were both obviously increased under straw-film mulching;carotenoid content was decreased relatively;hundred leaf weight,1 000-grain weight and yield of Lycium barbarum L.were increased to a certain extent,but there was no obvious effect on the shape of fruit.Besides,the yield of Lycium barbarum L.had no significant positive correlation with total carbohydrate and polysaccharide,almost had no correlation with flavonoids,and had no significant negative correlation with carotenoid.[Conclusion] The reasonable mulching could improve the yield and quality of Lycium barbarum L..

Effects of Ground Mulching Treatments on Soil Moisture Content in Second-generation Seed Garden of Pinus elliottii

Different ground mulching treatments were designed to observe the effects on soil moisture content in a second-generation seed orchard of Pinus elliottii. The results showed that： （1） there were extreme differences in soil moisture content Ⅰ and soil moisture content Ⅲ, but no obvious difference in soil moisture content II was observed; and （2） the high-to-low order of soil moisture content Ⅰ under different ground mulching treatments was white film〉sawdust〉black film〉the control, and the highest value was higher than the lowest one by 26.69%; the high-to-low order of soil moisture content Ⅱ under different ground mulching treatments was white film〉black film〉sawdust〉the control, and the highest value was higher than the lowest one by 20.64%; and the high-to-low order of soil moisture content Ⅲ under different ground mulching treatments was black film〉white film〉sawdust〉the control, and the highest value was higher than the lowest one by 26.61%.

Light Simplified Millet Production Technique Adopting Film Mulching and Hole Sowing

In order to solve the problem that dry-land foxtail millet production completely relies on rainwater with low instable yield and tedious cultivation, Millet Research Institute of Hebei Academy of Agriculture and Forestry Sciences integrated a light simplified production technique integrating film mulching, hole sowing and fertilization with mechanized production, forming the light simplified foxtail millet production technique adopting film mulching and hole sowing. This study introduced the light simplified foxtail millet production technique adopting film mulching and hole sowing, including main links such as preparation before sowing, sowing, attached agricultural machines, field management, harvest and residual film recovery.

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.

Effect of Planting in Furrow and Whole Plasticfilm Mulching on Double Ridges on Improvement of Degraded Desert Grassland

[Objective] This study aimed to provide theoretical basis and technologies for the application of planting in furrow and whole plastic-film mulching on double ridges. [Method] The conventional method was used to re-seed the bunch Gramineous forage in the degraded desert grassland in Yanchi, Ningxia Hui Autonomous Region. Four kinds of conservation treatments, namely, ridging with black film mulching, ridging with transparent film mulching, ridging with no mulching and the flatplanting with no ridging and mulching were conducted to the forage to analyze the effects of each treatment on soil moisture and seedling growth. [Result] From July to November, the moisture contents of ridging with black film mulching, ridging with transparent film mulching, ridging with no mulching and the flatplanting were respectivery 9.88%, 9.24%, 8.75% and 8.13%, showing significant differences among the treatments; the survival rates of re-seeding forage were 96.2% , 93.4% , 45.6% and 28.3% , and the mulching treatment showed significant difference with the unmulching treatments in survival rate. The treatment with black film mulching showed great advantage that its moisture content on ridge top had the buffering effect of ＂load shifting＂, and the soil moisture content of black mulching treatment increased 21.5% than the flatplanting. Black film mulching also had the largest water supplement amount in soil below 1 m. Although mulching cost too much, its overall benefits were higher than that with no mulching. [Conclusion] This study lays the experimental basis for the application of planting in furrow and whole plastic-film mulching on double ridges in improving degraded grassland desertification.

Soil mulching can mitigate soil water defi ciency impacts on rainfed maize production in semiarid environments

Temporally irregular rainfall distribution and inefficient rainwater management create severe constraints on crop production in rainfed semiarid areas. Gravel and plastic film mulching are effective methods for improving agricultural productivity and water utilization. However, the effects of these mulching practices on soil water supply and plant water use associated with crop yield are not well understood. A 3-yr study was conducted to analyze the occurrence and distribution of dry spells in a semiarid region of Northwest China and to evaluate the effects of non-mulching （CK）, gravel mulching （GM） and plastic film mulching （FM） on the soil water supply, plant water use and maize （Zea mays L.） grain yield. Rainfall analysis showed that dry spells of ≥5 days occurred frequently in each of 3 yr, accounting for 59.9-69.2% of the maize growing periods. The 〉15-d dry spells during the jointing stage would expose maize plants to particularly severe water stress. Compared with the CK treatment, both the GM and FM treatments markedly increased soil water storage during the early growing season. In general, the total evapotranspiration （ET） was not significantly different among the three treatments, but the mulched treatments significantly increased the ratio of pre- to post-silking ET, which was closely associated with yield improvement. As a result, the grain yield significantly increased by 17.1, 70.3 and 16.7% for the GM treatment and by 28.3, 87.6 and 38.2% for the FM treatment in 2010, 2011 and 2012, respectively, compared with the CK treatment. It＇s concluded that both GM and FM are effective strategies for mitigating the impacts of water deficit and improving maize production in semiarid areas. However. FM is more effective than GM.

The status and distribution characteristics of residual mulching film in Xinjiang, China

Pollution of residual plastic film in arable lands is a severe problem in China. In this study, the status of residual film and influential factors were investigated using the methods of farm survey in combination with questionnaires and quadrat sampling at a large number of field sites in Xinjiang Uygur Autonomous Region, China. The results showed that the amount of film utilization increased largely and reached to 1.8×10~5 t in 2013. Similarly, the mulching area also substantially increased in recent decades, and reached to 2.7×10~5 ha in the same year. According to the current survey, 60.7% of the sites presented a greater mulch residue than the national film residue standard（75 kg ha^（–1））, and the maximum residual amount reached 502.2 kg ha^（–1） in Turpan, Xinjiang. The film thickness, the mulching time and the crop type all influenced mulch residue. The thickness of the film had significantly negative correlation with the amount of residual film（P0.05）, while the mulching years had significantly positive correlation with it（P0.05）. The total amount of residual film in Xinjiang was 3.43×105 t in 2011, which accounted for 15.3% of the cumulative dosage of mulching. Among all the crops, the cotton fields had the largest residual amount of mulch film（158.4 kg ha^（–1））, and also the largest contribution（2.6×10~5 tons） to the total amount of residual film in Xinjiang.