Effect Of Straw Application Research Articles

Effects of straw application on soil hydrothermal conditions and crop yield in a maize and wheat rotation system

Effects of straw application on soil hydrothermal conditions and crop yield in a maize and wheat rotation system

Rape straw application facilitates Se and Cd mobilization in Cd-contaminated seleniferous soils by enhancing microbial iron reduction

Many naturally seleniferous soils are faced with Cd contamination problem, which severely limits crop cultivation in these areas. Straw returning has been widely applied in agricultural production due to its various benefits to soil physicochemical properties, soil fertility, and crops yield. However, effects of straw application on the fates of Se and Cd in Cd-contaminated seleniferous soils remain largely unclear. Therefore, the effects of straw application on the fates of Se and Cd in Cd-contaminated seleniferous soils were investigated in this study. The results showed that iron reduction driven by Clostridium and Anaeromyxbacter was responsible for the variations in Se and Cd fates in soil. Straw application respectively increased the gene copy numbers of Clostridium and Anaeromyxbacter by 19.5–56.3% and 33.6–39.8%, thus promoting iron reductive dissolution, eventually resulting in a high release amount of Se and Cd from Fe(III) (oxyhydr) oxides. Under reducing conditions, the released Cd was adsorbed by the newly formed metal sulfides or reacted with sulfides to generate CdS precipitates. Straw application decreased the soil exchangeable Se and soil exchangeable Cd concentration during flooding phase. However, straw application significantly increased Se/Cd in soil solution which had the highest bioavailability during flooding. In addition, straw application increased soil exchangeable Se concentration, but it had no significant effects on soil exchangeable Cd concentration after soil drainage. Taken together, straw application increased Se bioavailability and Cd mobility. Therefore, straw application is an effective method for improving Se bioavailability, but it is not suitable for the application to Cd-contaminated paddy soils. In the actual agricultural production, straw could be applied in seleniferous soils to improve Se bioavailability. At the same time, straw application should be cautious to avoid the release of Cd from Cd-contaminated soil.

The influence of application hyperaccumulator plant straw on photosynthetic pigment content and photosynthetic parameter of lettuce under cadmium stress

Pot experiments were conducted to study the effects of straw application of three hyperaccumulator plants (Solanum nigrum, Bidens pilosa and Galinsoga parviflora) influence photosynthetic pigments content and photosynthetic parameters of lettuce (Lactuca sativa) under Cd stress. The results showed that: compared with no straw application, the photosynthetic pigment content of lettuce was increased by applying three kinds of hyperaccumulator plants straw (S. nigrum, B. pilosa and G. parviflora), but there was no significant difference among the three kinds of hyperaccumulator plant straws; also improved the net photosynthetic rate (Pn), Stomatal conductance (Gs), transpiration rate (Tr), intercellular CO2 concentration (Ci) of lettuce, among them, the effect of G. parviflora straw was the most obvious. Application of three kinds of hyperaccumulator plant straw promoted the growth of lettuce by increasing the photosynthetic pigment content and photosynthetic parameter of lettuce under Cd stress.

Effects of hyperaccumulator plant straw on biomass and cadmium accumulation of lettuce

To study the effects of hyper-accumulator plant straw on the biomass and cadmium (Cd) accumulation of lettuce (Lactuca sativa), the pot experiments were conducted to study the effects of straw application of three hyper-accumulator plants (Solanum nigrum, Bidens pilosa and Galinsoga parviflora) on the biomass and Cd accumulation of lettuce under Cd stress. The results show that: compared with no straw application, the biomass of lettuce was increased after applying three kinds of hyper-accumulator plant straw: S. nigrum, B. pilosa and G. parviflora, Cd content in the above ground part of lettuce was increased by 4.46%, 1.20% and 0.63% respectively, compared with that of non-application, and Cd content in the root of lettuce was decreased. The application of three kinds of hyperaccumulator plant straw promoted the growth of lettuce and increased Cd uptake by lettuce of aerial part.

Effects of straw application on nitrate leaching in fields in the Yellow River irrigation zone of Ningxia, China

A five-year field experiment was conducted to investigate the effects of straw application on nitrate leaching loss. Treatments included soil that was not treated (control), soil treated with straw at a low rate (4,500 kg ha−2, T1) and soil treated with straw at a high rate (9,000 kg ha−2, T2). Nitrate-nitrogen leaching in the 10, 20, 30, 60, and 90 cm soil layers was measured using the resin-core method. The results indicated that straw application could reduce soil nitrate leaching losses in the 0–30 cm layer. In this layer, the nitrate leaching values for T1 (13.76 kg ha−2) and T2 (13.74 kg ha−2) were both significantly lower than those of the control (15.76 kg ha−2) (P < 0.05); the soil nitrate leaching losses decreased by 12.71% and 12.84% for those two treatments, respectively. However, no significant differences in losses were observed (P > 0.05) between T1 and T2. The effects of straw application were apparent only in the ploughing layer (30 cm-depth soil layer). In the deeper layers (60 and 90 cm), no significant differences were observed between the treatments and the control, and the same results were observed in the topsoil layers (10 and 20 cm).

Effect of Straw Application on the Dynamics of Exogenous Nitrogen and Microbial Activity in Paddy Soil

Returning straw to the field provides an important source of fertilizer that can increase soil fertility. However, the rate of straw carbon utilization is low and large amounts of greenhouse gases are emitted due to the high carbon to nitrogen ratio of the straw mass. In this regard, the application of inorganic nitrogen and phosphate fertilizers can control the ratio of elements in the soil, increase the activity of microorganisms and their utilization of elements, and promote the improvement of soil fertility. In this study, straw application conditions were simulated, and inorganic nitrogen fertilizer labeled with 15N was added to examine the effects of different nutrient fertilizer additions on the transformation and distribution of exogenous nitrogen in the soil, and also the characteristics of the microbial response. The results showed that application of straw increased the contents of ammonia nitrogen and total nitrogen in the soil and soil solution. When both straw and inorganic nitrogen fertilizer were applied, the 15N-TN in the soil remained at 28 to 33 μg during the 100-day culture phase. In contrast, 15N-NH4+ increased gradually during the initial 30 days of the culture phase, but subsequently decreased gradually. Application of phosphate increased the contents of 15N-TN and 15N-NH4+ in the soil, but decreased the content of 15N in the soil solution by 28%. The distribution of inorganic nitrogen in the soil showed that the proportion of 15N in the soil remained at 52%-61%. Addition of phosphate fertilizer increased the distribution ratio of 15N in the soil by up to 16.5%, whereas the proportion of 15N in the soil solution decreased from 36% on the fifth day to 30% on the 100th day, thereby the loss amount of 15N reduced by 1.2-fold. Addition of straw promoted microbial activity and significantly increased the microbial biomass nitrogen (MBN) content of the soil. Addition of inorganic fertilizer further promoted the microbial activity of the soil. After the 100-day culture experiment, the addition of straw, inorganic nitrogen, and phosphate fertilizer increased MBN to between 2.0-fold and 2.2-fold that of the control treatments. Addition of phosphate fertilizer increased the utilization of 15N by microorganisms, so that the amount of 15N-MBN was 1.5-fold higher than that of treatments where only straw and nitrogen fertilizer were added. Examination of soil enzyme activity showed that nitrogen fertilizer reduced soil enzyme activity and substrate affinity. When both nitrogen and phosphate fertilizers were added, the enzyme activity was 48.1% higher than that when only straw was added. The findings of this study thus provide a theoretical basis for furthering our understanding on the nitrogen cycle of the paddy soil ecosystem, the improvement of soil fertility, and the reduction of greenhouse gas emissions.

Effects of straw application on coastal saline topsoil salinity and wheat yield trend

Owing to an irrigation water shortage and a shallow underground water table in coastal zones, soil salinization is becoming a serious and complicated problem. Different practices are being explored to reduce its negative effect on land productivity. In this work, the effect of combined straw and inorganic N applications at different rates on topsoil (0–20cm) salinity and wheat growth was evaluated in a coastal field. Maize straw was applied at the rates of 5.0×103kgha−1(S) and 1.0×104kgha−1 (2S) and inorganic N was applied at the rates of 75kgha−1(N1/2), 150kgha−1(N), and 300kgha−1(N2). Treatment without addition of straw but with inorganic N application at the rate of 150kgha−1 was used as the control (CK). Thus, there were six treatments: SN1/2, SN, SN2, 2SN, 2SN2, and CK. During the early growth stages (seedling, jointing, and booting) of wheat, straw application significantly decreased topsoil salinity from 13.8% to 30.4% in comparison to the CK treatment (p<0.05), and the decrease was enhanced with increase in the straw application rate. This positive influence decreased substantially during wheat growth. Soil dissolved organic carbon and microbial biomass carbon both increased significantly (p<0.05) after straw addition; in contrast, there was a significant reduction in available N from March to April. The greatest wheat grain yield and aboveground biomass were produced in 2SN2, and yield increased by 15.1% in comparison to CK. In contrast, yield decreased by 5.1–9.6% in SN, 2SN, and SN1/2. Thus, straw application may be an effective practice for reducing topsoil salinity in the coastal zones, and an adequate N supply should be applied to maximize crop yield.

基于秸秆还田条件下的黄灌区稻旱轮作土壤硝态氮淋失特征研究

基于秸秆还田条件下的黄灌区稻旱轮作土壤硝态氮淋失特征研究

Fate of nitrogen from green manure, straw, and fertilizer applied to wheat under different summer fallow management strategies in dryland

Returning crop residues to soil is an effective approach for sustaining organic matter concentrations and increasing nutrient availability in soils. A 2-year micro-plot field experiment was conducted in dryland to determine the green manure, straw, and fertilizer nitrogen (N)-15 uptake by wheat, their residual N in soil and losses; the effect of straw application on the fate of N from green manure and vice versa was also determined, as well as the effect of crop residue additions on the fate of fertilizer N. All the micro-plots were treated with the same amount of 15N-labeled or unlabeled fertilizer. The green manure N uptake by wheat, residual N, and N loss were 22.4, 51.7, and 25.9 % of the total added green manure N over the 2-year experiment. Straw addition significantly decreased the green manure residual soil N but increased the cumulative losses. The straw N taken up by wheat, residual N in soil, and N loss were 8.3, 31.0, and 60.7 %, respectively. Green manure addition significantly decreased the straw N taken up by wheat, increased the residual soil N, and reduced the N loss. Furthermore, the fertilizer N taken up by wheat, residual N in soil, and N loss were 32.4, 32.3, and 35.2 %, respectively. Crop residue additions significantly increased the uptake of fertilizer N by wheat in the second year. The application of inorganic N fertilizer in combination with appropriate crop residues may be an effective approach to improve the long-term fertilizer N use efficiency, soil quality, and crop yield in wheat–summer fallow rotation systems in dryland.

Effect of straw application on yield and phosphorus nutrition of crops

In greenhouse experiment, straw alone or with different phosphates, produced a negative effect on the growth of vetch crop in the first year of its application possibly due to immobilization of nitrogen and production of phytotoxic substances. Phosphate immobilization was not the cause of lower yields as noted in treatments with straw. A positive residual effect of straw on yield and P uptake was noted only in the second year. The residual effect of straw favoured the accumulation of humus and fulvic phosphates. The role of fulvic acid in the mobilization of mineral phosphates is emphasized. Precomposting of straw for a certain period with soil before the sowing of crop seems desirable to overcome the effects of immobilization of nitrogen and phytotoxic substances produced in the initial phase of its decomposition.