Effects Of Straw Mulching Research Articles

Effect of long-term straw mulching and no-tillage on physical properties of meadow soil in cold region.

The effects of different straw returning technology and farming system on soil physical properties is not clear in Heilongjiang Province, which is located in middle temperature zone with large amount of straw. Here, the effects of straw mulching on soil physical properties in meadow soil under no tillage conditions were studied in field experiments for eight consecutive years (2010-2017). The no straw covering (0%), 30% coverage (30%), 60% coverage (60%) and 100% coverage (100%) were disposed in the experiment. The results showed that straw mulching under no tillage significantly increased soil bulk density by 0.10-0.20 g·cm-3, which increased with the increases of coverage amount. Straw mulching increased soil solid fraction by 2.5%-7.8%. Soil temperature decreased with the increases of coverage amount, and this trend was more apparent on the surface of soil. The temperature reduction in 0-5 cm soil layer was 1.87-2.90 ℃. Soil water content significantly increased with the increases of straw mulching, with an enhancement of 6.4%-10.2%. Straw mulch decreased the total porosity and diameter of >0.05 mm aeration pores, increased the effective pore size of 0.05-0.002 mm, with the magnitude of such effects being positively dependent on coverage amount. There was no significant effect of straw mulching on inactive porosity of soil. Long-term straw mulching increased soil compaction and soil moisture, reduced soil temperature and total soil porosity, and increased soil available porosity in 0-5 cm soil layer.

Effect of straw mulch and seeding rate on the harvest index, yield and water use efficiency of winter wheat

Straw mulching has been used to improve water use efficiency (WUE, yield per unit evapotranspiration) in the Loess Plateau of China, but the seeding rate may need to be adjusted from conventional practice. We tested the three-way interaction between seeding rate, soil management (conventional tillage and straw mulching) and seasons. Wheat yield ranged from 2851 to 6981 kg ha−1 and WUE from 5.3 to 16.2 kg ha−1 mm−1. Generally, soil water storage was higher and soil temperature was lower under straw mulching than under conventional practice. Evapotranspiration was higher under straw mulching. Yield was significantly affected by the interaction between straw mulching and season. Conventional practice showed significantly higher mean harvest index (HI), yield, and WUE than straw mulching in favorable seasons. However, yield was significantly higher under mulching than under conventional tillage in very dry season. Seeding rate had no effect on yield, but low seeding rate increased HI compared to high seeding rate. It is concluded that low seeding rate would be suitable for straw mulching.

Effects of straw mulching on soil evaporation during the soil thawing period in a cold region in northeastern China

To study the effect of straw mulching on soil water evaporation, it is necessary to measure soil water evaporation under different conditions of straw mulching during the soil thawing period. A field experiment was conducted in winter, and soil evaporation was measured using a microlysimeter on bare land (LD) and 4500 (GF4500), 9000 (GF9000) and 13500 $$\hbox {kg/hm}^{2}$$ (GF13500) straw mulch. The influence of different quantities of straw mulch on soil water evaporation during the thawing period was analyzed using the Mallat algorithm, statistical analysis and information cost function. The results showed that straw mulching could delay the thawing of the surface soil by 3–6 d, decrease the speed at which the surface soil thaws by 0.40–0.80 cm/d, delay the peak soil liquid water content, increase the soil liquid water content, reduce the cumulative evaporation by 2.70–7.40 mm in the thawing period, increase the range of soil evaporation by 0.04–0.10 mm in the early stage of the thawing period, and reduce the range of soil evaporation by 0.25–0.90 mm in the late stage of the thawing period. Straw mulching could reduce the range of and variation in soil evaporation and can reduce the effect of random factors on soil evaporation. When the amount of straw mulch exceeded 9000 $$\hbox {kg/hm}^{2}$$ , the effect of increasing the amount of straw mulch on daily soil water evaporation was small.

Effects of straw mulching and plastic film mulching on improving soil organic carbon and nitrogen fractions, crop yield and water use efficiency in the Loess Plateau, China

A field experiment was conducted in the Loess Plateau of Northwest China to study the effects of plastic film mulching and straw mulching on soil water, soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC) and nitrogen (MBN), dissolved organic carbon (DOC) and nitrogen (DON), crop yield and water use efficiency under winter wheat (Tricicum aestivum L.)—summer maize (Zea mays L.) double-cropping system conditions using the following three cultural practices: (i) traditional plough with no mulching (CK), (ii) traditional plough with plastic film mulching (PM), and (iii) traditional plough with straw mulching (SM). Soil water contents were measured by the gravimetric method. SOC was determined using the dichromate oxidation method. TN was analyzed by the Kjeldahl method. MBC and MBN were determined using the chloroform fumigation extraction method. DOC and TDN were determined following Jones’ procedures proposed by Jones and Willett (2006). The results showed that soil water was higher under the PM treatment than under the SM treatment and mainly changed in the upper 60 cm soil layer. Compared with the CK treatment, the concentrations of SOC and TN under the SM treatment were increased by 16.9% and 7.7% at the 0–10 cm soil depth, respectively, and the PM treatment had the similar SOC and TN concentrations. Compared with the CK treatment, soil C:N ratio was increased under the SM treatment by 6.2% (P < 0.05), and that under the PM treatment was decreased by 5.2% (P < 0.05) after three years. The concentrations of MBC under the PM and SM treatments were significantly increased by 42.0% and 24.1%, respectively, and MBN under the PM treatment was significantly increased by 5.6% at 0–10 cm soil depth after the maize season. Compared with the CK treatment, DOC was significantly increased by 21.0% under the SM treatment and decreased by 13.1% under the PM treatment, and DON was significantly increased by 10.5% under the SM treatment and decreased by 4.3% under the PM treatment at the 0–10 cm soil depth after the maize season. Relative changes of labile soil organic carbon and nitrogen fractions were more sensitive than that of SOC and TN. The relative decline or increase of labile soil organic carbon and nitrogen fractions was on average almost 13.6% for the mulching practices. Compared with the CK treatment, the average maize yields under the PM and SM treatments were increased by 26.4% and 9.8%, and the average wheat yields under the PM and SM treatments were increased by 21.3% and 7.4%, respectively. The average water use efficiencies under the PM and SM treatments were 24.5%, 8.8% in winter wheat and 22.9%, 6.3% in summer maize higher than that under the CK treatment, respectively. Our results suggested that plastic film mulching could be used as an effective practice to improve low soil quality with adequate nitrogen and increase crop yield and water use efficiency in the Loess Plateau, China.

Effects of straw mulching on microclimate characteristics and evapotranspiration of drip-irrigated winter wheat in North China Plain

Field experiments were conducted for two consecutive years (2013–2014 and 2014–2015) to study the effects of straw mulching on microclimate characteristics, energy flux, soil evaporation (Es) and evapotranspiration of winter wheat (Triticum aestivum L.) under adequate drip irrigation in North China Plain (NCP). The results revealed that straw mulching affected air temperature (Ta) and dew point temperature (Td) near the soil surface but had little effect on relative humidity (RH) compared with non-mulched fields. Straw mulching increased the turbulent exchange coefficient (K), and K within the canopy was higher than that above the canopy. Straw mulching clearly increased the sensible heat flux (H) distribution in April–June, and part of the energy needed for evapotranspiration was provided by transfer from the warmer air aloft. There was a linear functional relationship between H and Ta measured above and within the canopy. The straw mulching decreased Es but increased crop transpiration (T). Mulched treatment (TM) can decrease the total irrigation amount by about 7%-15% compared with the non-mulched treatment (TN). There were no significant differences (p>0.05) in cumulative crop evapotranspiration (ETc) between TM and TN treatments under adequate drip irrigation, and the use of mulch may need to be combined with an optimal deficit drip irrigation schedule for managing the declining water table in NCP. Keywords: drip irrigation, microclimate, straw mulching, winter wheat, evapotranspiration, water use efficiency DOI: 10.25165/j.ijabe.20181102.3192 Citation: Wang J D, Zhang Y Q, Gong S H, Xu D, Snyder R, Chen Y Y, et al. Effects of straw mulching on microclimate characteristics and evapotranspiration of drip-irrigated winter wheat in North China Plain. Int J Agric & Biol Eng, 2018; 11(2): 122–131.

Effects of Straw Mulching and Vegetative Covering on Soil Salinity Dynamics of Salt Affected Soils in Jiangsu Coastal Region, China

Effects of Straw Mulching and Vegetative Covering on Soil Salinity Dynamics of Salt Affected Soils in Jiangsu Coastal Region, China

Research on the effect of straw mulching on the soil moisture by field experiment in the piedmont plain of the Taihang Mountains

Research on the effect of straw mulching on the soil moisture by field experiment in the piedmont plain of the Taihang Mountains

Evapotranspiration, crop coefficient and yield for drip-irrigated winter wheat with straw mulching in North China Plain

A field experiment was conducted for three consecutive years (2013.10–2016.6) to study the effects of straw mulching with three drip-irrigation schedules on crop evapotranspiration (ETc), crop coefficient (Kc), grain yield (Y) and water-use efficiency (WUE), and the three drip irrigation lower limits and upper limits were from 55% field capacity (FC) to 75% FC, 65% to 85% FC and 75% and 100% FC respectively. Mulching significantly decrease the total irrigation amount compared with non-mulched when the soil water content was remaining within 65%–85% FC. Mulching also significantly (p<0.05) decrease the seasonal crop evapotranspiration (ETcs) and increased Y when soil water content was remaining within 75%–100% FC. Under the same sufficient drip irrigation schedule, mulching significantly increase the WUE. Mulching decreased the total cumulative soil evaporation (Es) amount to 19–34mm, and mean daily Es was significantly reduced by 25%–41% compared with non-mulching. The Kc of well-watered treatments agreed well with the corrected Kc-FAO curve, and the corrected Kc-FAO for this study field may underestimate the real Kc of winter wheat for the mid-season. Generally, straw mulching did not significantly alter the Kc value (p>0.05) compared with non-mulched treatments under the same drip-irrigation schedule when winter wheat entered the fast development stage. The straw mulching not only clearly decreased evaporation coefficient Ke, but also increased basal crop coefficient Kcb of winter wheat. In addition, with the same less water irrigation or seasonal crop evapotranspiration (ETcs) consumption, mulching had potential advantage of improving Y. Finally, the treatment with soil water content remaining within 65%–85% FC and combined with straw mulching, was an optimal combination of drip-irrigation schedule with agronomy for winter wheat irrigation management in the North China Plain.

Effect of straw mulch and integrated nitrogen management on yield and quality of turmeric under North Indian plains

The continuous application of nitrogen (N) through chemical source has shown deleterious effect on productivity of turmeric, whereas availability of organic source is very limited to meet the nitrogen requirement. Therefore it was considered worth to study the impact of integration of chemical and organic source of N on productivity of turmeric. A three-year field experiment was conducted at Punjab Agricultural University, Ludhiana, during 2011–12 to 2013–14 to study the response of turmeric to straw mulching and N applied through different combinations of organic manure (FYM) and N-fertilizer (urea). Application of paddy straw as mulch @ 6.25 t ha−1 significantly increased the plant height, number of tillers, mother, primary and secondary rhizomes, rhizome weight and yield of turmeric. The fresh rhizome yield increased by 85.0 and 34.9% during 2011–12 and 2012–13, respectively, due to mulch application over no-mulch. A slight improvement was noticed in curcumin content, however, the difference between mulch and no-mulch treatments was non-significant. Application of 125 kg N/ha through FYM alone, produced the highest rhizome yield during all study years (20.6, 22.36 and 23.17 t/ha during 2011–12, 2012–13 and 2013–14, respectively), which was, however, statistically at par with the application of two-third and half of organic manure along with one-third and half of N through urea, respectively. Nitrogen substitution through urea beyond 50% resulted into reduced growth and fresh rhizome yield. Hence, integration of 50% of N (62.5 kg/ha) through organic manure (FYM) and 50% of N through fertilizer urea enhanced the turmeric yield as compared to 100% N fertilizer alone. Quality parameter in terms of curcumin content did not show any significant differences with the different combinations of integrated nitrogen source.

Effects of straw mulching on initial post-fire vegetation recovery

Straw mulching is increasingly used after high severity wildfires for reducing post-fire runoff and erosion but can alter post-fire vegetation regeneration. However, information about the extent to which mulching affects the recovery of native vegetation is inconclusive. The soil seed bank plays an important role in the resilience of frequently disturbed shrubland communities but little is known about how it is affected by mulching treatments. In this study, we assessed the effects of straw mulching (2.0Mgha−1) on the recovery of vegetation after a wildfire in Galicia (NW Spain). For this purpose, we carried out a greenhouse and field-based study to evaluate the effects of mulching applied immediately after fire on the soil seed bank and recovery of vegetation cover in a shrubland area during the first year after wildfire. In the greenhouse, there were no differences in the total number of seedlings that emerged from the soil seed bank of mulched and untreated samples (634 seedlings m−2 vs 731 seedlings m−2). Species richness increased from 22 in untreated burned soils to 24 species in the mulched, burned soils. In the field, straw mulching favoured plant establishment and recovery of vegetation cover. At the end of the first post-fire year, plant cover was significantly higher (63%) in the mulching treatment compared to the untreated one (44%). Mulching did not affect species composition, and there was little evidence of the presence of non-native species. The results indicate that, in the present case, straw mulching immediately after the fire favoured recovery of plant cover in the first year after the fire by conserving the soil moisture.

Combined effects of runoff and soil erodibility on available nitrogen losses from sloping farmland affected by agricultural practices

The susceptibility of purple soil and intensive tillage render the land prone to erosion under heavy precipitations in a sloping cropland in southwestern China. This study aimed to improve the evaluation of the potential benefits of surface protection tillage and organic matter addition to decreasing nutrient losses. A field plot experiment under natural rainfall conditions was conducted, which employed four management practices: conventional downslope tillage system as control (CK), contour tillage (CT) with organic matter addition (CT+OM), CT with wheat straw mulching (CT+SM), and CT combining straw mulching and organic matter addition (CT+OM+SM). Runoff depth, nutrient loads, and soil erodibility were used to estimate the effects of straw mulching and organic matter addition. Results indicated that the runoff depth under CK was largest during the experimental period, with an average of 16.91mm, and runoff coefficient average was 32%. Compared with CK, the runoff depth under CT+OM, CT+SM, and CT+OM+SM were reduced by 19%, 34%, and 50%, respectively. A significant difference in soil erodibility indicator among the four treatments was indicated (p<0.05); CK achieved the highest value, whereas CT+OM+SM obtained the least value. In addition, the contour cultivation (i.e., CT approaches) were more sustainable than the downslope tillage system (i.e., CK). Soil erodibility under CK was 9.83kgha−1mm−1. Meanwhile, soil erodibility under CT+OM, CT+SM, and CT+OM+SM were 8.49, 6.99, and 6.87kgha−1mm−1, respectively. These values were 14%, 29%, and 30% lower than that of CK, respectively. CK was more susceptible to accelerated erosion compared with the plots with a surface cover or organic addition. This greater erodibility resulted in higher runoff, sediment yield, and associated nutrient loss for CK. The runoff-associated nitrogen losses were mainly controlled by the runoff rate and soil erodibility (p<0.05). Variations in NO3−–N and NH4+–N concentration in runoff water were markedly affected by rainfall events and agricultural practice. A significant logarithmic correlation between NO3−–N load and runoff depth was identified. NO3−–N was proven to be the main form of inorganic nitrogen loss; therefore, fertilizer application of NO3−–N should be reduced in the purple soil region. Soil erodibility significantly influenced the available N losses (p<0.01), which was best described by a positive logarithmic correlation. Soil nutrient concentration also played an important role in nitrogen loss. However, further research is needed to understand the dynamic interactions between soil erodibility as well as soil and nutrient losses. Results indicated that surface protection by CT+OM+SM is one of the good management practices to reduce soil loss by water erosion in regions with intense agricultural activity.

Effects of Straw Mulching on Soil Physicochemical Properties in Saemangeum Reclaimed Land

To identify the effects of straw mulching on soil physicochemical properties in reclaimed saline soil, field experiment was conducted for 3 years (2010~2012) in Saemangeum reclaimed land. Soil series of the experimental field was Munpo and soil texture was fine sandy loam. The experiment was conducted at a field with EC of 2.4 dS m -1 (field Ⅰ) and the other field with EC of 5.6 dS m -1 (field Ⅱ). Each experimental field was treated with rye straw incorporation, mulching with rye straw and control. In 2010 rye straw produced from other field was used for the experiment and in 2011~2012 rye straw cultivated at the same experimental field was used. After rye straw application, soybean was cultivated. After 3 years field experiment, by rye straw incorporation, soil salinity decreased from 2.4 dS m -1 to 0.6 dS m -1 at fieldⅠ but increased from 5.6 dS m -1 to 7.6 dS m -1 at field Ⅱ. By mulching with rye straw soil salinity decreased from 2.4 dS m -1 to 0.5 dS m -1 at field Ⅰ and also decreased from 5.6 dS m -1 to 0.5 dS m -1 at field Ⅱ. By rye straw incorporation and mulching soil organic matter increased from 2 g kg -1 to 4 g kg -1 . At field Ⅰ yields of soybean were similar between rye straw incorporation and mulching but at field Ⅱ yield of soybean increased apparently by mulching with rye straw compared to rye straw incorporation and control.

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures in a rainfall simulation

Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80mm rainfall event (80 mm$h -1 for 60 min), 8% ,1 2% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treat- ments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400-3100 kg$hm -2 ) is recom- mended for the conservation of water and soil in northern China.

Effects of straw mulching on maize photosynthetic characteristics and rhizosphere soil micro-ecological environment

Straw mulching is an effective measure to improve soil properties, crop growth, and yield. To further understand the advantage mechanisms of straw mulching, a field experiment with seven straw mulching levels (0 to 18 000 kg ha-1) was conducted to study the effects of straw mulching on maize (Zea mays L.) photosynthesis and rhizosphere soil micro-ecological environment. Results showed that maize chlorophyll content was evidently affected by straw mulching, and the highest chlorophyll content was at 12 000 kg ha-1 (M4). Straw mulching could significantly improve the photosynthetic characteristics of maize, and the difference between M4 and 0 kg ha-1 (M0) was significant. There was as trend change in soil microbe quantity; it first increased and then decreased with increasing straw mulching levels, and the most suitable straw mulching level for different types of microorganisms was 9000 kg ha-1 (M3) or M4. Straw mulching significantly enhanced soil enzyme urease, invertase, dehydrogenase, and protease activities, but when the straw mulching level reached a certain level, the effect of straw mulching was no longer apparent and even had some adverse effects at straw mulching levels higher than 15 000 kg ha-1 (M5). Yield in M4 (10 186.84 kg ha-1) was the highest compared with M0 (9365.12 kg ha-1), and yield significantly increased by 8.8%. Correlation analyses indicated that the soil microbe quantity and aforementioned enzyme activities were all significantly and positively correlated with maize chlorophyll content, photosynthetic rate, and yield. Findings suggest that straw mulching can apparently increase soil microbe quantity and enzyme activities and improve crop photosynthesis and yield; the M4 level is the most reasonable straw mulching level in this study under comprehensive consideration, and a straw mulching level that is too high (over M5) will have some negative effects.

Effects of soil deformation and surface mulching on soil physical properties and soybean response related to weather conditions

A field experiment was conducted on Haplic Luvisol developed from loess to assess the effects of soil deformation and straw mulch on soil water status (matric potential), temperature, penetration resistance, soybean growth, seed yield and yield components including straw, protein and oil in 2006–2008. Water use efficiencies related to the amount of rainfall during the growing seasons were calculated for seeds and total above ground biomass. The soil deformation levels (main plots) comprised the following trials: non-compacted (NC, 0 tractor pass), moderately compacted (MC, 3 passes), and strongly compacted (SC, 5 passes). A uniform seedbed in all plots was prepared by harrowing before planting. The main plots included sub-plots without and with surface wheat straw mulch (0.5kgm−2) and the corresponding trials were NC+M, MC+M, SC+M. The amount and distribution of rainfall during the growing season differed among the experimental years with extended drought at bloom-full seed (R2-R6) stages in 2006, good water supply in 2007, and alternative periods with relatively high and low rainfalls in 2008. The effect of soil deformation on matric potential was influenced by weather conditions, soybean growth phase, mulching and depth. The differences were greatest in 2007 and 2008 at R7-R8 growth stages. With increasing deformation level from NC to SC matric potential for 0–15cm depth during these stages significantly decreased from −401 to −1184kPa in 2007 and from −1154 to −1432kPa in 2008. On mulched soil, the corresponding ranges were from −541 to −841kPa and from −748 to −1386kPa, respectively. In the dry summer 2006, the differences were smaller and less consistent. Irrespective of soil deformation level, mulching reduced soil temperature in most growth phases but most pronounced initially. Most yield components increased from NC to MC during the experiments which could be attributed to enhanced root water and nutrient uptake rates and decreased from MC to SC due to high soil strength that restrained root growth down to deeper depth. The yields of seeds, straw, protein and oil as well as water productivity of soybean seed and biomass were improved by mulching in 2007–2008. This improvement was more pronounced in 2007 when the mean yield of seeds, protein and oil were significantly greater by 16, 29 and 11%, respectively and was attributed to positive alterations in soil water retention. These results indicate the possibilities of improvement in soybean performance by identifying allowable amount of traffic and mulching practices at planting depending on weather fluctuations during the growing season. Since rainfall and air temperature distribution in 2007 are close to those averaged over a long period of time, the use of straw mulch may positively affect soybean performance and yields excluding anomalously dry years. The positive effect of straw mulch can be enhanced by moderate soil deformation combined with seedbed loosening before planting to avoid constraining effect of soil structure on crop establishment.

Effects of straw mulch on soil water and winter wheat production in dryland farming.

The soil water supply is the main factor that limits dryland crop production in China. In a three-year field experiment at a dryland farming experimental station, we evaluated the effects of various straw mulch practices on soil water storage, grain yield, and water use efficiency (WUE) of winter wheat (Triticum aestivum). Field experiments were conducted with six different mulch combinations (two different mulch durations and three different mulch amounts): high (SM1; 9000 kg ha−1), medium (SM2; 6000 kg ha−1), and low (SM3; 3000 kg ha−1) straw mulch treatments for the whole period; and high (SM4), medium (SM5) and low (SM6) straw mulch treatments during the growth period only, where the control was the whole period without mulch (CK). Throughout the whole growth period of the three-year experiment, the average soil water content in the 0–200 cm soil layer increased by 0.7–22.5% compared with CK, while the WUE increased significantly by 30.6%, 32.7% and 24.2% with SM1, SM2, and SM3, respectively (P < 0.05). The yield increased by 13.3–23.0% when mulch was provided during the growth period, while the WUE increased by 15.2%, 17.2% and 18.0% with SM4, SM5, and SM6, respectively, compared with CK.

Effect of Straw Mulch on Runoff and NPS Pollution Reduction from Experimental Plots under a Climate Change Scenario in Korea

AbstractThis study attempted to quantify the effects of rice straw mulches on runoff and nonpoint source (NPS) pollution under a future climate change scenario. For this, regression equations between the observed rainfall and runoff curve number (CN) were developed to estimate NPS pollution from radish fields. Rainfall data from the special report on emissions scenarios (SRES) A1B were applied to the regression equations in order to predict future runoff and NPS pollution by surface covers. The results show that future rainfall was estimated to increase by 0.8% in the 2020s, 14.4% in the 2050s, and 15.1% in the 2080s. Under the projected rainfall conditions, the loose straw and the straw mat mulches were estimated to reduce runoff by 65.7 to 66.8% and 95.8 to 96.9%, respectively, while the selected pollutants were reduced by 44.1 to 98.8% and 58.9 to 94.9%, respectively. Both types of straw mulch were effective in controlling both runoff and NPS pollution, and thus offer a very promising means to cope wit...

Straw Mulching Reduces Maize Yield, Water, and Nitrogen Use in Northeastern China

Straw mulching is used widely to improve soil fertility in the black soil region of northeastern China, but there have been few evaluations of its effects on soil water content, N use by crops, and crop growth. Field experiments were conducted during two growing seasons in Jilin Province, to study the effects of straw mulching on maize yield, evapotranspiration (ET), water use efficiency (WUE), and nitrogen use efficiency (NUE) under rainfed conditions. Measurements were conducted in a treatment with maize straw mulch on the soil surface (SM) and a control treatment with no mulch (NM). The SM treatment caused a significant decline of soil temperature and increase of soil moisture in the early growing season, compared to the NM treatment. However, the use of mulching reduced maize yields by 18% in 2011 and 26% in 2012. It also decreased WUE by 16% in 2011 and 21% in 2012, and decreased NUE by 27% in 2012, though it had no effect on total ET. Therefore, the use of mulch is not recommended as an approach for improving water and N use and maize yields, in the semi‐humid black soil region of northeastern China, when the water content of soil is sufficient for maize growth.

Effectiveness of Straw Mulch on Infiltration, Splash Erosion, Runoff and Sediment in Laboratory Conditions

Abstract Mulches have extraordinary potential in reducing surface runoff, increasing infiltration of water into the soil and decreasing soil erosion. The straw mulches as a biological material, has the ability to be a significant physical barrier against the impact of raindrops and reduce the detachment of soil aggregates. The present study is an attempt to determine the efficiency of straw mulch as conservation treatment in changes in the splash erosion, time-to-runoff, runoff coefficient, infiltration coefficient, time-to-drainage, drainage coefficient, sediment concentration and soil loss. The laboratory experiments have been conducted for sandy-loam soil taken from deforested area, about 15 km of Warsaw west, Poland under lab conditions with simulated rainfall intensities of 60 and 120 mmh–1, in 4 soil moistures of 12, 25, 33 and 40% and the slope of 9%. Compared with bare treatments, results of straw mulch application showed the significant conservation effects on splash erosion, runoff coefficient, sediment concentration and soil loss and significant enhancement effects on infiltration and drainage. The results of Spearman-Rho correlation showed the significant (p &lt; 0.05) correlation with r = –0.873, 0.873, 0.878 and 0.764 between rainfall intensity and drainage coefficient, downstream splash, sediment concentration and soil loss and with r = –0.976, 0.927 and –0.927 between initial soil moisture content and time-to-runoff, runoff coefficient and infiltration coefficient, respectively.

Effects of straw mulch on growth and yield of durum wheat during transition to Conservation Agriculture in Mediterranean environment

In Mediterranean environment, the transition to Conservation Agriculture (CA) poses as major issue the scarce accumulation of residues on soil surface; covering the soil with additional straw mulch could be a proven strategy for soil and water conservation, especially where durum wheat is the main crop, until reaching a layer of adequate thickness, typical of the stabilized CA systems.Two field trials were carried out from 2010 to 2012 in a representative area of Southern Italy during the first two years of transition to CA. Durum wheat was grown under three increasing levels of straw added as soil mulching: 5.0tha−1 (100% mulch cover (100%MC)), 2.5tha−1 (50%MC) and 1.5tha−1 (30%MC), plus a CONTROL. The influence of such additional straw on soil water and nutrient availability, physiological traits, growth and yield of durum wheat was assessed, as well as the necessary amount of additional straw was estimated.Both years of study indicated that root-zone moisture contents, monitored at 5cm depth starting from the beginning of head emergence, were significantly improved by mulching, with the highest differences detected between 100%MC and CONTROL (36 and 41% higher in 2011 and 2012, respectively). 100%MC exhibited also the significant lowest concentration of nitrate-N (9mgL−1 on average), K, Ca and Mg in soil solution. Additional straw at higher rates improved crop physiology: leaf water content (LWC) was highest in 100%MC (48.3%) and lowest in CONTROL (38.2%); SPAD and NDVI values (chlorophyll content) were respectively increased by 25% and 22% in 100%MC and by 15% and 17% in 50%MC, with respect to CONTROL. Nitrogen Nutrition Index (NNI) at anthesis was highest in 100%MC (0.97 vs. 0.50 in CONTROL). Significant high correlations were found between yield components and water as well as NO3− availability in soil solution (number of grainsm−2 vs. NO3− in soil solution R2 0.89; number of grainsm−2 vs. soil water R2 0.96). Yield was significantly affected by crop dry weight and N status at anthesis (0.49kgm−2 in 100%MC vs. 0.27kgm−2 in CONTROL, averaged over years). Moreover, the plots with higher amount of additional straw (100%MC and 50%MC) promoted significantly the accumulation of nitrogen in grains (0.56mgNgrain−1 in 2011 and 0.51mgNgrain−1 in 2012 in 50%MC).Under our experimental conditions, 1.5tha−1 of straw added as mulching are enough to significantly produce higher yields, although to exert significant positive effects both on soil and on crop physiological indicators, 2.5tha−1 of wheat straw are necessary. However, increasing the amount of crop residues until 5tha−1, crop performances and soil characteristics continue to significantly improve.