Mulching Patterns Research Articles

Effects of small ridge and furrow mulching degradable film on dry direct seeded rice

Global climate change and socio-economic development have led to a shortage of water and labour resources, which has had a significant impact on rice cultivation. In this study, the application of micro-ridge-furrow planting technology and degradable film mulching in dry direct-seeded rice was investigated to address the factors restricting the development of the rice industry and reduce the impact of rice production on the environment. The effects of a micro-ridge-furrow planting pattern and degradable film mulching on soil temperature, seedling growth, and yield of dry direct-seeded rice in a semiarid region of China were studied through three field experiments: micro-ridge-furrow mulching with traditional plastic film (T1); micro-ridge-furrow mulching with degradable film (T2); and traditional flat-cropping mulching with traditional plastic film (CK). The experimental results demonstrated that the micro-ridge-furrow mulching film planting pattern promoted the germination of rice seeds and improved the soil temperature, plant height, leaf area, dry mass, and grain yield. T2 had the highest average soil temperature (14.68–17.83 ℃ during the day; 14.4–15.74 ℃ at night), leaf area (41.85 cm2 plant−1), root dry mass (45.32 mg plant−1), shoot dry mass (58.46 mg plant−1), root–shoot ratio (0.821), and yield (8.112 t ha−1). In summary, the micro-ridge-furrow mulching with degradable film (T2) is recommended as an efficient planting and mulching pattern for sustainably solving environmental problems and improving grain yield in semiarid regions of China.

覆盖模式对旱作农田土壤微生物多样性及群落结构的影响

覆盖模式对旱作农田土壤微生物多样性及群落结构的影响

Can ridge-furrow with film and straw mulching improve wheat-maize system productivity and maintain soil fertility on the Loess Plateau of China?

Ridge-furrow mulching patterns are beneficial to improve crop yields and rainwater use efficiency, but it is not clear whether they can improve productivity and simultaneously maintain soil fertility on the Loess Plateau of China. A three-year (2013–2016) field trial was conducted during the rotation of wheat (Triticum aestivum L.) – maize (Zea mays L.) to investigate the effects of ridge-furrow mulching patterns on soil moisture, soil fertility, grain yield, and water use efficiency (WUE). Four ridge-furrow planting patterns included: (1) white plastic film mulch over the ridge (RW), (2) straw mulch over the furrow (RS), (3) white plastic film mulch over the ridge and straw mulch over the furrow (RWS), and (4) black plastic film mulch over the ridge and straw mulch over the furrow (RBS). Flat planting without mulch was CK. The results showed that RW, RS, RWS, and RBS significantly improved soil water storage and aboveground biomass throughout each winter wheat and summer maize growing season compared with CK. Finally, winter wheat grain yield and WUE in the four mulching treatments markedly increased by 13.0–32.9% and 22.5–41.5% in a wet and cool season, 15.5–35.2% and 19.3–41.9% in a season with normal rainfall and temperatures, and 27.2–58.9% and 15.3–33.4% in a dry and warm season, respectively. Maize grain yield and WUE increased by 12.8–35.0% and 19.5–46.2% in a season with normal rainfall and temperature, 15.0–38.5% and 18.0–39.9% in a dry and cool season, and 17.4–50.5% and 13.0–42.5% in a dry and warm season, respectively. Among the four mulching treatments, RWS and RBS significantly improved the yield and WUE of wheat and maize relative to RW and RS over the three years. After three years, soil total nitrogen content in RWS and RBS was significantly greater than in RS. Besides, soil microbial biomass carbon and nitrogen, and soil dissolved organic carbon and nitrogen contents in RWS and RBS were all markedly higher than in RW and RS. Our results indicated that RWS and RBS were a promising agricultural practice that improved crop production and simultaneously maintained soil fertility in a rain-fed semi-arid region of China.

Response of productivity and nitrogen efficiency to plastic-film mulching patterns for maize in sub-humid northeast China

In the semi-humid region of northeast China, the plastic-film mulching (PFM) is essential for sustaining yields, while the yield-increase potential and nitrogen (N) use mechanism under different PFM patterns in this area remain poorly understood. A field experiment using maize (Zea mays L.) was conducted for two consecutive years to study the effects of different PFM patterns on soil microclimate factors, N mineralization, N loss, crop yields and N use efficiency under drip irrigation. The six treatments consisted of full ridge-furrow mulching (FM), only ridge mulching (RM), non-mulching (NM), ridge-furrow mulching without fertilization (CFM), ridge mulching without fertilization (CRM), and non-mulching without fertilization (CNM). The results showed that the PFM could obviously warm the soil throughout the growing season. Compared to NM, FM and RM obviously increased the soil temperature by 2.0–5.4 ℃ and 1.6–4.8 ℃ in the 2017 season, respectively, and by 1.9–7.8 ℃ and 1.0–5.7 ℃ in the 2018 season, respectively. Across two years, soil temperature was highest for FM followed by RM and NM. In general, FM enhanced the soil water content compared with RM, especially in the 0–50 cm profile throughout the growing season. The PFM could significantly (p < 0.05) promote soil N mineralization (Nmin). Furthermore, irrespective of fertilization, the PFM significantly (p < 0.05) improved plant N uptake (Nuptake), grain N accumulation (Ngrain) and N harvest index (NHI). Averaged across years, full ridge-furrow mulching and only ridge mulching distinctly enhanced the NHI under fertilization by 6.8% and 6.1%, respectively, relative to non-mulching. Finally, PFM imposed significant influence (p < 0.05) on ear barren tip, 100-seed weight and grain yield. Grain yield under FM and RM were significantly promoted by 15.0% and 12.5%, respectively, compared with NM. Meanwhile, full ridge-furrow mulching could obviously increase grain yield compared to ridge mulching. In conclusion, full ridge-furrow mulching provided a more feasible water-heat environment for soil N mineralization, improving plant N uptake and reducing N loss, and thereby significantly increasing crop productivity and nitrogen use efficiency.

Soil hydro-thermal characteristics, maize yield and water use efficiency as affected by different biodegradable film mulching patterns in a rain-fed semi-arid area of China

The farming practice of fully mulched double ridge-furrow with polyethylene (PE) film has been widely used to improve productivity of many staple crops in arid and semi-arid regions of northwest China. However, the residual PE film has caused many environmental problems such as “white pollution” and land degradation. Biodegradable film might be a good substitute for PE film in agriculture production, but the evidence for the appropriate biodegradable film mulching pattern for maize is lacking. A 2-year field experiment was carried out to identify a suitable biodegradable film mulching pattern for maize at a typical rain-fed semi-arid site on the Loess Plateau. The local widely cultivated maize variety ‘Luodan 9′ was sown in five planting patterns: 1) conventional flat planting without film mulching (CK); 2) flat planting with full mulching with biodegradable film (FB); 3) ridge-furrow planting with biodegradable film mulching on ridges (RFB); 4) double ridge-furrow planting with full biodegradable film mulching (DRFB) and with full transparent PE film mulching (DRFP). The results indicated that biodegradable film mulching patterns (including FB, RFB and DRFB) significantly increased soil hydrothermal conditions, improved leaf area index, shoot and root biomass, and thus enhanced maize yield and water use efficiency (WUE) in comparison to CK (P < 0.05). Among the three biodegradable film mulching patterns, maize yield and WUE in DRFB (average across two growing seasons) were 9.7% and 11.7% significantly greater than FB, and were 9.9% and 12.2% significantly greater than RFB. In addition, maize yield and WUE in DRFB did not differ significantly from those in DRFP, except that the maize yield was 5.2% (P < 0.05) lower than DRFP in 2013 (a warm and dry season). Present field demonstration clearly indicated that DRFB could serve as a promising option to ameliorate soil hydrothermal conditions, improve maize growth and yield performance, boost WUE, and simultaneously reduce environmental risks such as “white pollution” in rain-fed semi-arid regions of northwest China.

Evaluating the effects of plastic film mulching patterns on cultivation of winter wheat in a dryland cropping system on the Loess Plateau, China

Plastic film mulching (PFM) can increase or stabilize crop yields worldwide when applied to agricultural planting systems, especially in arid and semi-arid areas. Although the adverse effects that are caused by residual plastic film, such as plastic pollution, are becoming a global concern, the application of PFM will not be replaced by other materials in the short-term in agriculture. It is important to understand the various PFM patterns (different mulching periods and coverage rates) that impact on soil physicochemical properties and characteristics of crop growth. Therefore, based on a field experiment that we established in 2002, we conducted consecutive field observations from 2013 to 2016 to determine the optimum PFM mulching period and coverage rate. Three mulching periods were included: (I) summer fallow period (FM), (II) growth period (GM), and (III) whole growth year (WM). Two coverage rates were included: (i) 50%, half mulching (HM), and (ii) 100%, total mulching (TM). That is, there were six different PFM treatments. No mulching (NM) over the growth years was considered the CK treatment. PFM increased canopy height and leaf area index of winter wheat (Triticum aestivum L.) in the growing season by 29.5% and 19.4%, respectively. Average winter wheat grain yields of various PFM patterns were 5318.5 kg ha−1 and 4557.7 kg ha−1 in 2013–2014 and 2015–2016, respectively; these yields were 13.8% and 23.7% higher than NM in 2013–2014 and 2015–2016, respectively. However, the difference in the growth characteristics and grain yield of winter wheat under various PFM patterns resulted from the change in the mulching period and coverage rate. Winter wheat grain yield and biomass increased with GM and WM compared with FM and NM in normal rainfall years. PFM coverage rates improved yield significantly (P < 0.05) and influenced soil nutrient concentrations. HM maintained or increased soil organic matter (SOM) and total nitrogen concentrations, but TM decreased SOM concentration by 8.3%. Water use efficiency (WUE) and rainfall use efficiency (RUE) were improved by various PFM patterns. Furthermore, WM had the most significant impact on SOM concentrations, GM was second, and FM was minor. Considering the costs and benefits of PFM patterns, the half coverage rate of PFM during the whole year (FWH) had the best index (BI) value, and the total coverage rate of PFM during the growth period (FGT) and the half coverage rate of PFM during the growth period (FGH) had higher BI values than other PFM patterns; the values for BI for FWH, FGT, and FGH were 10.3, 8.9, and 8.5, respectively. In conclusion, ignoring the amount of PFM pollution in the environment (or use biodegradable film instead of polyethylene film), FWH was the best PFM pattern with the highest WUE and RUE in dryland rainfed agriculture. But, to decrease the amount of PFM application and pollution, FGH was more beneficial for soil health with a low coverage rate and short mulching period. FGH was the optimal pattern for PFM when applied to winter wheat on the Loess Plateau, China based on our field experiment.

Effects of degradable film mulching on crop yield and water use efficiency in China: A meta-analysis

Degradable film (DF) has recently been demonstrated to be a good alternative to plastic film (PF) for mulching crops such as maize, wheat, potato and cotton. Whether or not the yield-increasing and water-saving effects of DF mulching vary with DF properties (type, color and thickness), field management (planting pattern) and environmental conditions (altitude, air temperature, rainfall and evaporation), however, are largely unknown. We therefore conducted a meta-analysis to: (1) determine the optimal type, color, thickness and mulching pattern of DF for maize, wheat, potato and cotton; and (2) identify the best environmental conditions of the yield-increasing and water-saving effects of DF mulching for maize, wheat, potato and cotton. The yield and water-use efficiency (WUE) for maize, wheat, potato and cotton were significantly higher for DF than non-film (NF) mulching, except for potato WUE. Yield and WUE for maize, wheat and cotton were lower with DF than PF. The properties of DF, planting pattern and environmental conditions greatly influenced the yield-increasing and water-saving effects of DF mulching. For maize, these effects were best at altitudes of 1000–1500 m, air temperatures of 10–15 °C, rainfalls of <500 mm, evaporation>2000 mm and effective accumulated temperatures of 2000–4000 °C, and the optimal type, color and thickness were biodegradable film (BDF) or photodegradable film, black and 0.008 mm, respectively. For wheat, yield and WUE were highest with BDF, especially at altitudes of 500–1000 m, air temperatures of 5–15 °C, rainfalls of <1000 mm and effective accumulated temperatures of 2000–3000 °C. For potato, yield was markedly higher under white BDF with a thickness of 0.008 mm, especially at altitudes >1500 m, air temperatures of 5–10 °C, rainfalls of 500–1000 mm, evaporation of 1000–2000 mm and effective accumulated temperatures of 2000–3000 °C. For cotton, PF could be replaced by BDF with 0.010 mm thick for altitudes of 1000–1500 m, air temperatures of 10–15 °C, rainfalls of <500 mm, evaporation>2000 mm and effective accumulated temperatures of 3000–4000 °C. For each crop, yield and WUE using DF were higher with a ridge-furrow planting pattern than a flat planting pattern, but not significantly This study provides a basis for the reasonable application of DF. Reducing production costs, however, is also very important in order to popularize DF mulching to a larger area.

Organic mulching positively regulates the soil microbial communities and ecosystem functions in tea plantation

BackgroundDifferent mulches have variable effects on soil physicochemical characteristics, bacterial and fungal communities and ecosystem functions. However, the information about soil microbial diversity, community structure and ecosystem function in tea plantation under different mulching patterns was limited. In this study, we investigated bacterial and fungal communities of tea plantation soils under polyethylene film and peanut hull mulching using high-throughput 16S rRNA and ITS rDNA gene Illumina sequencing.ResultsThe results showed that the dominant bacterial phyla were Proteobacteria, Actinobacteria, Acidobacteria and Chloroflexi, and the dominant fungal phyla were Ascomycota, Mortierellomycota and Basidiomycota in all samples, but different mulching patterns affected the distribution of microbial communities. At the phylum level, the relative abundance of Nitrospirae in peanut hull mulching soils (3.24%) was significantly higher than that in polyethylene film mulching soils (1.21%) in bacterial communities, and the relative abundances of Mortierellomycota and Basidiomycota in peanut hull mulching soils (33.72, 21.93%) was significantly higher than that in polyethylene film mulching soils (14.88, 6.53%) in fungal communities. Peanut hull mulching increased the diversity of fungal communities in 0–20 cm soils and the diversity of bacterial communities in 20–40 cm soils. At the microbial functional level, there was an enrichment of bacterial functional features, including amino acid transport and metabolism and energy production and conversion, and there was an enrichment of fungal functional features, including undefined saprotrophs, plant pathogens and soils aprotrophs.ConclusionsUnique distributions of bacterial and fungal communities were observed in soils under organic mulching. Thus, we believe that the organic mulching has a positive regulatory effect on the soil bacterial and fungal communities and ecosystem functions, and so, is more suitable for tea plantation.

Effects of plastic mulch and nitrogen fertilizer on the soil microbial community, enzymatic activity and yield performance in a dryland maize cropping system

AbstractFarming practices that integrate plastic film mulching and nitrogen (N) fertilization have been extensively used to enhance crop productivity. However, the interactive effects of mulching and N application on soil microbial properties and crop yields have received little attention. A 2‐year field experiment was carried out in the Loess Plateau to investigate the independent and combined effects of plastic mulch and N application rate on the soil microbial population, enzymatic activity and grain yield. From 2016 to 2017, two mulching patterns (i.e., plastic mulching and no mulching) were exposed to five different N application rates (0 (N0), 80 (N80), 160 (N160), 200 (N200) and 240 (N240) kg N ha−1). N application significantly affected the soil microbial community composition, as suggested by significant increases in soil total bacteria, cellulose‐decomposing bacteria and the bacterial‐to‐fungal ratio with N rates. In contrast, the mulching pattern significantly affected soil extracellular enzyme production. Furthermore, there were significant effects of mulching, N application and their interaction on grain yield. The highest grain yield (11,728 kg N ha−1 in 2016 and 12,350 kg N ha−1 in 2017) in both growing seasons was consistently obtained under plastic mulching with a N level of 200 kg N ha−1. Our study showed that plastic mulching significantly affected extracellular enzyme production, and N fertilizer application significantly affected the composition of the soil microbial community.Highlights Independent and coupled effects of mulching and N application on soil biological properties and grain performance were explored. N application significantly influenced soil microbial community composition. Mulching pattern rather than N application independently and significantly affected soil extracellular enzyme production The combined application of plastic mulching with 200 kg N ha−1 should be seem as an optimum crop production pattern in this area.

Study on Water Saving Potential and Net Profit of Zea mays L.: The Role of Surface Mulching with Micro-Spray Irrigation

Water shortage threatens agricultural sustainability in Horqin Sandy Land, northeast China. To explore the effects of various surface mulching patterns with micro-spray irrigation on the yield, water consumption (ETc), and water-saving potential of maize (Zea mays L.), we used three treatments: straw mulching (JG), organic fertilizer mulching (NF), and no mulching (WG; control). In each treatment, plants were supplied with 500 mm of total water (irrigation plus precipitation) during the entire growing season and were irrigated with the amount of total water supply minus precipitation. Yield and water use efficiency (WUE) showed a significant negative correlation with water saving potential per unit yield (Py) and water saving potential per unit area (Sp), which were also consistent with their relationships in the function model. Meanwhile, a remarkably positive correlation occurred between yield, WUE, and net economic profit, respectively. The JG treatment, which was mainly affected by light and temperature production potential (Yc), grain yield, and ETc, showed the lowest Py (0.16 m3 kg−1) and Sp (2572.31 m3 hm−2), and the maximum increase in yield, WUE, and net economic profit, extending to 16,178.40 kg hm−2, 3.25 kg m−3, 17,610.09 yuan hm−2, respectively, which were significantly higher than those in NF and WG, (p &lt;0.05). Thus, straw mulching with micro-spray irrigation was the best treatment for maximizing yield and WUE. Organic manure mulching and no mulching need further investigation, as these showed high Py and Sp, which were together responsible for lower WUE.

Integrated Effects of Mulching Treatment and Nitrogen Fertilization on Cotton Performance under Dryland Agriculture

ABSTRACTCrop production in arid regions is characterized with high temperature, drought and salinity which decrease water and nutrient use efficiency. This study was conducted to investigate the effect of wheat residue mulch in relation to N fertilizer application rates for cotton productivity under dryland condition of Uzbekistan. Main plots were control of no mulch addition and a 5 t ha−1 mulch treatment. These plots were split into 5 N rate plots of 0, 70, 140, 210 or 280 kg of N ha−1. The results showed that mulching pattern decreased soil temperature by 0.7–1.5°C as compared to conventional treatment (CT), regardless of N fertilization rates. The soil water storage increased by 41.8, 17.3, 48.0 mm in the flowering, boll formation and ripening stages of cotton, respectively under mulching treatment. Soil available N concentration and nutrients uptake by plants consistently increased with the increase of N fertilization rates with positive correlations. At flowering period, the plant height, chlorophyll content, stem diameter, and a number of fruit branches in plants were higher by 32.3%, 46.8%, 26.7% and 55.3%, respectively at 210 kg N ha−1 under mulching treatment as compared to the non-fertilized control. The highest cotton yield was obtained at 210 kg N ha−1 application under mulching treatment. The correlation difference between mulch and N application rates was higher (R2 = 0.97) than the difference in CTs and N application rates (R2 = 0.89). This study showed that mulching had a greater impact to preserve nutrients and water resources in the soil, thereby improved cotton growth and yield.

Impact of farmland mulching practices on the soil bacterial community structure in the semiarid area of the loess plateau in China

Farmland mulching is widely used to preserve soil moisture and increase crop yield in the semiarid region of the Loess Plateau. However, the effect of different farmland mulching on soil bacterial communities is not clear. Therefore, the impact of a 5-year field management practice (surface mulching) on the soil bacterial communities was studied in dryland farmland of the Loess Plateau by using Illumina sequencing of the 16S rRNA gene. The following treatments were investigated: (1) ridge-furrow mulching pattern; (2) flat plastic film mulching; (3) flat biodegradable film mulching; (4) flat straw mulching; and (5) control (CK), conventional flat planting without mulch. All farmland mulching increased the diversity of soil bacteria and the diversity was greatest under the plastic film treatment. The dominant phyla across all soil samples were Proteobacteria, Acidobacteria, and Actinobacteria. Cluster analyses showed that bacterial communities under mulching treatments were different from that of CK. The bacterial community composition of plastic film and straw mulching treatments, biodegradable film and ridge-furrow mulching treatments were similar at the phylum level. Spearman correlation analysis indicated that the response of bacterial alpha-diversity was mainly negatively associated with the soil organic carbon and total nitrogen. The Mantel test showed that the beta-diversity depended primarily on the soil total nitrogen and soil temperature. The changes of the bacterial community distribution were significantly related to the soil moisture, which varied significantly with a range of 9.8–17.3 between treatments. These results indicated that soil properties changed after long-term farmland mulching, and these changes were related to soil bacterial diversity and community structure. According to this study, flat plastic firm mulching was found to being a good option for increasing soil bacterial diversity and richness and thereby potentially stabilize functional stability of soil biological processes.

Effects of different long-term farmland mulching practices on the loessial soil fungal community in a semiarid region of China

The Northwest Loess Plateau is a typical area of dryland agricultural production in China. Farmland mulching is often used to preserve the soil moisture and increase crop yields. However, the impacts of long-term farmland mulching practices on the soil fungal communities in the loessial soil in semiarid areas of China were less explored. Thus, we investigated the variations in the soil fungal communities under different mulching patterns using high-throughput sequencing to understand how different mulching practices affect these communities. The following treatments were investigated: ridge-furrow mulching pattern (R), flat plastic film mulching (P), flat biodegradable film mulching (B), flat straw mulching (S), and conventional flat planting without mulching as a control (CK). Farmland mulching practices significantly affected the soil fungal diversity and community structure by changing the soil properties. Compared with CK, the P and S treatments significantly increased the soil fungal diversity, thereby suggesting that these practices provided the most suitable growth environment for fungi. The soil moisture and nitrate nitrogen (NO3-N) content were the most important factors that affected the fungal diversity. Nonmetric multidimensional scaling ordination showed that the fungal communities in CK were separated from those in R and B treatments and closely clustered with the communities in the P and S treatments, thereby suggesting that the fungal community compositions differed slightly between the P and S treatments and the CK treatment, but the soil fungal community compositions in the R and B treatments differed significantly from that in CK. In addition, the fungal community composition depended primarily on the soil temperature and NO3-N. These results indicate that different farmland mulching practices affected the soil moisture, soil temperature, and NO3-N to change the soil fungal community distribution patterns in this region. Overall, the soil fungal diversity and abundance were both higher in the P treatment than the other treatments. Therefore, flat plastic film mulching is recommended for semiarid areas.

Improved yield and water storage of the wheat-maize rotation system due to double-blank row mulching during the wheat stage

Mulching techniques have been widely used in dryland regions in northern China. It is necessary to develop water-saving cultivation techniques in irrigation regions in northern China to relieve water scarcity. Planting and mulching on separate rows has been widely used to improve wheat yield and involves a pattern of a double row of planting and a blank row of mulching. However, whether the mulching pattern during the wheat season can be applied to the wheat-maize system to increase the yield of both crops and to reduce the use of irrigation water remains unclear. Three mulching practices (conventional planting (CP), conventional planting with mulching (CPM) and double-blank planting with mulching (DPM)) during the wheat season were conducted to verify the potential roles of DPM in increasing wheat and maize yields, improving soil temperature and enhancing water storage under the DPM practice. The results show that the DPM practice significantly increased the efficiency spike number, aboveground biomass and grain yield (7.8% higher than CP and 11.3% higher than CPM) of wheat. The heat conservation effect of the DPM practice was stronger in the early stage of growth and was more effective in minimizing fluctuations in soil temperature in the wheat season compared with CPM. The development and yield of maize that was sowed in the mulching lines of DPM were less improved, although the amount of aboveground biomass at the maturity stage was higher. Additionally, the soil temperature of the maize season under DPM showed a narrowing trend of changes during the early stage with slight effects in the middle stage and a resumption of heat conservation in the late stage. Compared with CP, both mulching patterns decreased soil evaporation during the two crops’ seasons by an average 5.3% in CPM and 7.8% in DPM, which is particularly evident when the crops’ leaf area index was low. Therefore, the DPM pattern could more effectively optimize soil temperature and water storage. Furthermore, this pattern may have positive effects on the yields of winter wheat and on reducing the soil water requirement of the maize season.

Effects of Plastic Film Mulching Patterns and Irrigation on Yield of Summer Maize and Greenhouse Gas Emissions Intensity of Field

In order to evaluate the effect of different treatments on yield and greenhouse gas emissions during the summer maize growing season, a two-year film mulching experiment was conducted in 2014 and 2015. In this experiment, the two main experimental factors were rainfed treatment (R) and irrigated treatment (I), and the secondary experimental factors included control treatment (CK), half film mulching treatment (HM), and full film mulching treatment (FM). The emissions of soil greenhouse gases (CO2, CH4, and N2O) were monitored using a static opaque chamber and chromatography method. Moreover, the greenhouse gas emissions intensity (GHGI) was used to evaluate the effect of carbon sequestration in different treatments. The results of this study showed that the yields of the RHM and RFM treatments did not differ significantly in 2014, but increased by 19.6% and 26.8%, respectively, in 2015 compared with that of RCK. The yield of IHM was not improved, and that of IFM significantly increased by 14.1% and 55.8% in 2014 and 2015, respectively, compared with that of ICK. The irrigated treatments only promoted CO2 emissions in 2015 (P<0.01), and all film mulching treatments (regardless of HM and FM treatments) had no effect on CO2 emissions under rainfed and irrigated conditions (P>0.05). Irrigated treatments had no effect on the absorption of CH4 (P>0.05), whereas the film mulching treatments had an inhibitory effect. Compared with values of RCK, the amount of seasonal N2O emissions for ICK showed a significant difference in 2015 with a decrease of 22.3%. Compared with values of RCK, the amounts of N2O emissions for RHM and RFM had no significant differences in 2014, but significantly decreased by 50.7% and 51.4% in 2015, respectively. Compared with ICK, IHM and IFM significantly decreased the amounts of N2O emissions by 47.5% and 54.2% in 2014, and by 9.6% and 52.2% in 2015, respectively. The GHGIs of RHM and RFM were significantly reduced by 60.1% and 61.7% in 2015, respectively, compared with values of RCK, and the GHGIs of IHM and IFM were significantly reduced by 39.7% and 53.2% in 2014, and reduced by 22.2% and 67.5% in 2015, respectively, compared with that of ICK. This means that the effect of FM on reducing GHGI was better than that of HM. It was also found that the significantly reduced GHGI in irrigated treatments may be attributed to the increased yields. Therefore, FM under irrigation conditions was recommended for summer maize for stabilizing the yield and reducing the GHGI.

Alternate row mulching optimizes soil temperature and water conditions and improves wheat yield in dryland farming

Straw mulching allows for effective water storage in dryland wheat production. Finding a suitable straw mulching model that facilitates wheat growth was the objective of this study. A 2-year field experiment was conducted to investigate the effects of two straw mulching patterns (FM, full coverage within all the rows; HM, half coverage within alternate rows) and two mulching rates (4.5 and 9.0 t ha−1) on soil moisture, soil temperature, grain yield, and water use efficiency (WUE) of winter wheat in northern China, with no mulching (M0) as the control. Results showed that mulching increased the soil water storage in all growth stages under high mulching rates, with a stronger effect in later growth stages. Water storage under the HM model was greater in later stages than under the FM model. Soil water content of HM groups was higher than that of FM groups, especially in surface soil layers. Evapotranspiration decreased in mulched groups and was higher under high mulching rates. Aboveground biomass during each growth stage under the HM model was higher than that under M0 and FM models with the same mulched rate, leading to a relatively higher grain yield under the HM model. Mulching increased WUE, a trend that was more obvious under HM9.0 treatment. Warming effect of soil temperature under the HM pattern persisted longer than under the FM model with the same mulching rates. Accumulated soil temperature under mulched treatments increased, and the period of negative soil temperature decreased by 9–12 days under FM and by 10–20 days under HM. Thus, the HM pattern with 9.0 t ha−1 mulching rate is beneficial for both soil temperature and water content management and can contribute to high yields and high WUE for wheat production in China.

Effect of film mulching and microbial inoculation on maize growth and water use efficiency under drought stress.

To resolve the problem of soil nutrient and water deficiency in arid and semiarid regions of Northwest China, and considering the symbiotic relationship between microbes and crops, we set up two water regimes: drought stress (35% of the soil water holding capacity) and normal water supply (75% of the soil water holding capacity), two film mulching patterns (non-film mulching and film mulching), and four levels of microbial inoculation [single inoculation with AM fungi (AM), single inoculation with phosphate solubilizing bacteria (PSB), co-inoculation of AM fungi with phosphate solubilizing bacteria (AM+PSB) and the control (CK)]. This study aimed to evaluate the effects of microbial inoculation on maize growth, nutrient absorption, and water use efficiency under different treatments of water regime and film mulching. Results showed that drought stress significantly increased the mycorrhizal colonization of inoculated plants, but significantly decreased soil external hyphal length, T-GRSP and EE-GRSP content. Under drought stress, AM inoculation showed the best promoting and mycorrhizal effect on maize growth by increasing biomass and water use efficiency, soil organic carbon content, the absorption and transportation of soil N, P, K, and thus increasing the N, P, K uptake. Under normal water supply, the inoculation effect of AM+PSB was better than that of AM or PSB treatment, especially combined with film mulching. Results from correlation analysis showed that plant biomass, leaf SPAD value, and nutrient uptake of maize aboveground were significantly positively correlated with soil external hyphal length, whereas water use efficiency was significantly negatively correlated with soil external hyphal length.

Effects of plastic film mulching patterns on maize grain yield, water use efficiency, and soil water balance in the farming system with one film used two years.

The aim of this study was to develop cost-saving and efficiency-improving technologies in whole plastic mulching and double ridge-furrow maize in semi-arid region of Loess Plateau. The objective was to investigate soil water balance in farming system with one film used two years. A field experiment was conducted to investigate the effects of different mulching and tillage patterns under one film used two years conditions on the yield, economic benefits, and water use efficiency of maize. There are four treatments: Ridge-furrow planting with complete plastic film mulching, F1M; flat-planting with complete plastic film mulching, F2M; flat-planting with half plastic film mulching, F3M; and flat-planting without mulching, F4M, the control. The results showed that the F1M and F2M treatments had significant effects on the improvement of the production and efficiency compared with the control. The F1M and F2M treatments improved biomass by 32.8% and 32.9%, enhanced grain yield by 60.0% and 51.7%. Water use efficiency and rainfall use efficiency in F1M and F2M treatments were increased by 59.8%, 35.9% and 87.6%, 64.4%, respectively. Furthermore, gross output value and input-output ratio of F1M and F2M treatments under every new plastic film mulched pattern were enhanced by 51.0%, 41.2% and 15.1%, 16.2%, respectively. The production pattern on cost-saving and efficiency-increasing of the system on double ridge-furrow and flat planting with one film used two years, this pattern increased gross output value by 40.8%, 42.2%, and increased input-output ratio by 40.3%, 42.2%, respectively. Under the condition of low precipitation (606.5 mm), total water consumption of ridge-furrow and flat planting under the system of one film used within two years was 731.3 mm and 746.8 mm, the soil moisture deficit was 124.8 mm and 140.3 mm, with enhancement of 22.7% and 38.0%, respectively. The total water consumption of ridge-furrow and flat planting treatments was reduced by 28.6% and 30.0%, and the fallow efficiency was improved by 178.9% and 148.3%. In conclusion, whole plastic mulching with double ridge-furrow and flat planting farming system had positive effects on yield and water use efficiency in semi-arid region of Loess Plateau. Combined with the technology of one film used within two years, this cropping system could be cost saving and efficiency increasing. However, the water deficit under low water condition should be seriously considered in practice.

Film-mulched continuous ridge-furrow planting improves soil temperature, nutrient content and enzymatic activity in a winter oilseed rape field, Northwest China

Film mulching system is a widely employed agricultural practice worldwide. However, the effects of different planting and mulching patterns on soil nutrient content and enzymatic activity have not been well documented. In this study, we examined the impact of four planting and mulching patterns (including control, flat planting without mulching; M1, flat planting with film mulching; M2, ridge-furrow planting with film mulching on both ridges and furrows; and M3, ridge-furrow planting with film mulching on continuous ridges) on the seed yield of winter oilseed rape, soil moisture, soil temperature, soil organic carbon (SOC) content, soil nutrient content, and soil enzymatic activity over three growing seasons from 2012 to 2015 in a winter oilseed rape field in the semi-arid area of Northwest China. Seed yield of winter oilseed rape, soil moisture, soil temperature, enzymatic activities, and contents of nitrate-nitrogen, available phosphorus, and available potassium were all significantly higher in mulching treatments (M1, M2 and M3) than in control treatment over the three growing seasons, whereas SOC content was significantly lower in mulching treatments than in control treatment during 2013–2014 and 2014–2015. Among the three mulching treatments (M1, M2 and M3), the M3 treatment showed consistently higher seed yield, SOC content, nutrient contents, and enzymatic activities than the other two treatments. Seed yield of winter oilseed rape was 41.1% and 15.0% higher in M3 than in M1 and M2, respectively. SOC content and soil enzymatic activities in the top 0–20 cm soil layers and nitrate-nitrogen content in the top 0–30 cm soil layers were all significantly higher in M3 than in M1 and M2. Therefore, we advise the ridge-furrow planting with film mulching on continuous ridges (i.e., M3) as an efficient planting and mulching pattern for sustainably improving the seed yield of winter oilseed rape and preserving soil fertility in the semi-arid area of Northwest China.

Yield loss compensation effect and water use efficiency of winter wheat under double-blank row mulching and limited irrigation in northern China

Maize straw residues as a surface mulching material would be an effective soil water-saving practice in wheat production for a wheat-maize rotation system in northern China. Additionally, combining a mulching pattern and limited irrigation could play an important role in enhancing the productivity of winter wheat. Therefore, open field experiments were carried out during 2012–2014 to study soil water content in depth, water use efficiency (WUE), soil temperature, wheat grain yield and root parameters under a mulching pattern [each-row mulching (ERM) and double-blank row mulching (DRM) with three mulching masses of 0. 4.5 and 9.0tha−1] and limited irrigation [no irrigation (I0) and one-time irrigation in winter (I1)].Results indicated that wheat yields increased (mean 3.3%) or decreased (mean 5.4%) a little under ERM groups with no irrigation. Irrigation for each row of mulch increased the wheat yield (mean 8.8%). With or without irrigation, yields under DRM0 were lower compared to ERM0, whereas, DRM4.5 and DRM9.0 had a higher grain yield than ERM4.5 and ERM9.0 (mean 25% under I0 and 18.8% under I1) as well as DRM0 (mean 24.1%). The DRM patterns with a high yield could have an equal effect with irrigation in winter. Additionally, irrigation could enhance the effects of DRM on wheat yield increase (mean 6.87tha−1in DRM4.5 and 7.06tha−1 in DRM9.0). Effective tillers and above-ground biomass would be the key factors for determining wheat yield, especially under certain mulching patterns, although these effects were not reflected in wheat roots.Mulching on soil temperature had a more significant difference in an early growth period than the later stages of wheat. An additional feature was that the DRM pattern had a persistent heat preservation effect in the regrowth stage, while there was a lower soil temperature in ERM groups in this stage when there was no irrigation. Mulching managed to shorten the period of negative accumulated temperatures of wheat (mean of 7days under ERM and 15days under DRM) under I0. Winter water irrigation enhanced the shorten effect to a certain extent. Mulching had a more significant water conservation effect in the overwinter stage with lower precipitation and higher soil evaporation. Soil water content under DRM groups was richer than ERM groups in the late growth stage, when there was lower plant density and evapotranspiration, but there was a higher yield and WUE (with a mean of 18.6% under I0 and 20.3% under I1).The results suggest that the DRM pattern optimizes soil temperature, water content, balance roots and group effects as well as increasing wheat yield. Thus, this approach could be a better field management option for wheat growth and yield production under the limitations of water in northern China.