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1.
This work was aimed at providing a sustainable approach in the use of manure in irrigated maize crop under Mediterranean climatic conditions. To this end, the effect of continuous annual applications of dairy cattle manure, combined or not with mineral N fertilizer, on the following parameters was studied: grain yield, grain and plant N concentration, N uptake by plant, N use efficiency, and soil N and organic carbon. The experiment was conducted in a furrow-irrigated sandy soil under dry Mediterranean conditions during seven years. Three different rates of cattle manure (CM): 0, 30 and 60 Mg ha−1, were applied each year before sowing. These CM rates were combined with four mineral N rates (0, 100, 200 and 300 kg N ha−1) applied at sidedress.On average, the highest grain yields during the 7 years were obtained with the combination of CM at 30 Mg ha−1 and mineral fertilizer and with CM at 60 Mg ha−1 without mineral fertilizer. With CM at 30 Mg ha−1, mineral fertilizer increased yields during most of the growing seasons, meanwhile with CM at 60 Mg ha−1, there was not any significant effect of the joint application of mineral fertilizer on yields. Overall, best results were obtained exceeding maximum rates according to present legislation. The mean apparent nitrogen recovery (ANR) fraction during the 7 seasons was 29% for N exclusively applied as CM. Overall, increased N rates applied as CM resulted in decreased ANRs. However, ANR with CM at 30 and 60 Mg ha−1 increased during the first two seasons. This increased ANR ascribed to mineralization of residual organic N applied in previous seasons explained the increasing yields observed in the treatments along the study.The application of CM during 7 years increased the soil organic carbon in the first 30 cm by 5.7 and 9.9 Mg ha−1 with CM at 30 and 60 Mg ha−1, respectively, when compared to the initial stock. Thus, manure-based fertilization could be an alternative to mineral fertilizer in order to achieve high maize yields while improving soil quality under dry Mediterranean conditions. 相似文献
2.
Decreasing the corn (Zea mays L.) gap between the potential yield and farm yield and reducing the risk of grain yield of drought are very important for corn production in the Corn Belt of Northeast China (CBNC). To achieve a high and stable corn yield, the effects of supplementary irrigation on yield, water use efficiency (WUE) and irrigation water use efficiency (IWUE) were studied using a modelling approach. The Root Zone Water Quality Model 2 was parameterized and evaluated using two years of experimental data in aeolian sandy soil and black soil. The evaluated model was then used to investigate responses to various irrigation strategies (rainfed, full irrigation and 12 single irrigation scenarios) using long-term weather data from 1980 to 2012. Full irrigation guarantees a high and stable corn grain yield (12.92 Mg ha−1 and has a coefficient of variation (CV) of 14.8% in aeolian sandy soil; 12.30 kg Ma−1 and CV of 11.1% in black soil), but has a low water use efficiency (19.92 and 21.81 kg ha−1 mm−1) and a low irrigation water use efficiency (10.01 and 11.03 kg ha−1 mm−1). A single irrigation can increase corn yields by 3–35% for aeolian sandy soil and 5–35% for black soil over different irrigation dates compared with no irrigation. The most suitable single irrigation date was during late June to early July for aeolian sandy soil (yield = 10.73 Mg ha−1 and WUE = 27.94 kg ha−1 mm−1) and early to mid-July for black soil (yield = 11.20 Mg ha−1 and WUE = 27.70 kg ha−1 mm−1). The lowest yield risk of falling short of the yield goal of 8, 9, and 10 Mg ha−1 were 9.1%, 18.2%, and 33.33% in aeolian sandy soil and 3.0%, 15.25, and 21.2% in black soil when an optimized single irrigation was applied in late June or early July, respectively. Therefore, an optimized single irrigation should be applied in late June to early July with the irrigation amount to refill soil water storage of root zone to field capacity in CBNC. 相似文献
3.
In Maraba, Southwest Rwanda, coffee productivity is constrained by poor soil fertility and lack of organic mulch. We investigated the potential to produce mulch by growing Tephrosia vogelii either intercropped with smallholder coffee or in arable fields outside the coffee, and the effect of the mulch on coffee yields over two years. Two accessions of T. vogelii (ex. Gisagara, Rwanda and ex. Kisumu, Kenya) were grown for six months both within and outside smallholder coffee fields in the first year. Experimental blocks were replicated across eight smallholder farms, only a single replicate per farm due to the small farm sizes. The accession from Rwanda (T. vogelii ex. Gisagara) grew more vigorously in all experiments. Soils within the coffee fields were more fertile those outside the coffee fields, presumably due to farmers’ long-term management with mulch. Tephrosia grew less well in the fields outside coffee, producing only 0.6–0.7 Mg ha−1 of biomass and adding (in kg ha−1) 19 N, 1 P and 6 K in the mulch. By contrast, Tephrosia intercropped with coffee, produced 1.4–1.9 Mg ha−1 of biomass and added (in kg ha−1) 42–57 N, 3 P and 13–16 K in the mulch. Coffee yields were increased significantly by 400–500 kg ha−1 only in the treatments where Tephrosia was intercropped with coffee. Soil analysis and a missing-nutrient pot experiment showed that the poor growth of Tephrosia in the fields outside coffee was due to soil acidity (aluminium toxicity) combined with deficiencies of P, K and Ca.In the second year, the treatments in fields outside coffee were discontinued, and in the coffee intercrops, two Tephrosia accessions were grown in treatments with and without NPK fertilizer. Tephrosia grew well and produced between 2.5 and 3.8 Mg ha−1 biomass for the two accessions when interplanted within coffee fields, adding 103–150 kg N ha−1, 5–9 kg P ha−1 and 24–38 kg K ha−1. Tephrosia mulch increased yields of coffee by 400 kg ha−1. Combined use of NPK + Tephrosia mulch increased Tephrosia biomass production and in turn yielded an additional 300–700 kg ha−1 of coffee. Over the two years, this was equivalent to a 23–36% increase in coffee yield using Tephrosia intercropping alone and a further 25–42% increase in coffee yield when NPK fertilizer was also added. Agronomic efficiency (AE) of nutrients added were 30% greater when the Tephrosia mulch was grown in situ and the two cultivars of Tephrosia did not differ in AE. The AE of Tephrosia mulch was 87% that of NPK fertilizer, reflecting the rapid mineralization of Tephrosia mulch. There was a synergistic effect of Tephrosia mulch on the efficiency with which NPK fertilizer was used by coffee. The increase in coffee yields was positively related to the amount of nutrients added in the Tephrosia biomass. Tephrosia intercropping required 30 man-days ha−1 less than current farmer management due to reduced labour required for weeding, and benefit–cost ratios ranged between 3.4 and 5.5. The Tephrosia-coffee intercropping system offers great potential for agroecological intensification for smallholder farmers in the East African highlands. 相似文献
4.
Intensification of cropping systems in recent decades has increased their productivity but affected air, soil and water quality. These harmful environmental impacts are exacerbated in Maize Monoculture (MM) and hasten the need for solutions to overcome the trade off between crop yield and environmental impacts. In a three-year cropping systems experiment, a conventional intensive maize monoculture (MMConv), with a winter bare fallow, deep soil tillage, non-limiting irrigation was compared to three Low Input Cropping Systems (LI-CS) designed as alternatives to the conventional system. They were managed with decision-rules implemented to reach specific objectives of input reduction. The LI-CS designed with Integrated Weed Management (IWM) techniques and other sustainable cropping practices, were:(i) MMLI—an IWM Low Input MM; (ii) MMCT—a Conservation Tillage combined with cover crop MM; and (iii) Maize-MSW—an IWM maize grown in rotation with soybean and wheat. A comprehensive multi-criteria assessment was carried out to quantify the agronomic, economic, social, and environmental performances of each system. A canonical discriminant analysis of performance metrics revealed large differences between the four systems. Yields were significantly higher in MMConv (11.0 Mg ha−1) and MMLI (10.3 Mg ha−1) than in Maize-MSW (8.6 Mg ha−1) and MMCT (7.8 Mg ha−1). MMCT had the largest weed infestation (density and biomass) despite the greatest use of herbicides. The Herbicide Treatment Frequency Index (HTFI), used to indicate differences in herbicide use, revealed that the MMLI (HTFI = 1.0) and Maize-MSW (1.1) halved the herbicide use as compared to the MMConv (2.1), despite having similar weed abundance levels. The LI-CS, especially MMCT, produced high biomass winter cover crops and then less nitrogen fertilization was required as compared to MMConv. Gross margins in the MMLI (1254 € ha−1) and MMConv (1252 € ha−1) were higher than the MMCT (637 € ha−1) and Maize-MSW (928 € ha−1). MMLI and MMConv had similar labour requirements. Water drainage, pesticide leaching, energy use, and estimated greenhouse gas emissions were higher in MMConv than in the LI-CS in most years. Results from this research show good potential for the MMLI to reduce the environmental impacts of MMConv while maintaining its economic and social performance. 相似文献
5.
Maize production plays an essential role in global food security. In order to maintain both high quality and maize production, there is a great demand for fertilizers. The main objective of this work was to study, over two experimental seasons, the effect of a biofertilizer obtained from sewage sludge (SS) on the yield and on the quality of maize crops (Zea mays L.). The biofertilizer was applied in two ways: (i) to soil, at rates of 0, 10 and 20 Mg ha−1 before sowing, and (ii) via foliar fertilization, applying 0, 3.6 and 7.2 l ha−1 three times during each growing season accounting for a total rate of 0, 10.8 l ha−1 and 21.6 l ha−1. This study is novel because there are no previous studies of the effect of this biofertilizer on any agricultural crops. The results obtained show that, when the SS was applied directly to the soil, the macro- and micronutrients analyzed in both soil and leaves showed no significant differences between either of the fertilizer treatments. Foliar application of SS, however, increased the leaf concentrations of macro- and micronutrients. When the SS rate was 7.2 l ha−1, grain protein concentration increased significantly by about 30% and the yield increased significantly by about 17% compared with the control treatment (SS not applied). These results suggested that, in order to improve agricultural maize yields, quality and nutritional, this SS should be applied as a foliar fertilizer instead of applying it to soil. 相似文献
6.
In dryland agricultural systems, pig slurry (PS) is usually applied to cereal crops only at sowing, and slurries accumulate for the rest of the year in pits. In this context, a four-year experiment was established in order to evaluate the feasibility of PS applications at the barley or wheat tillering stage. The main treatments were PS either applied at sowing (25 Mg ha−1) or not, but they alternated after a two-year period. Both were annually combined with eight side-dressing treatments at cereal tillering: mineral N as NH4NO3 (M; 60 or 120 kg N ha−1 yr−1), PS from fattening pigs (PSf; 17, 30, 54 Mg ha−1 yr−1), PS from sows (PSs; 25, 45, 81 Mg ha−1 yr−1) and a treatment without N. The combined fertilization treatments were 18 plus a control (no N applied). In the context of crop rotation, the biennial alternation of PS applied at sowing allowed the control of soil nitrate increments, while PS side-dressing improved N recovery compared with a unique application at sowing. The highest yields (>3.6 Mg ha−1 yr−1) were obtained with an annual average (4-yr) N rate close to 173 kg N ha−1 (±40 kg N ha−1). The best overall strategies corresponded to PSs side-dressings of 50–90 kg N ha−1. These PSs rates also recorded the highest values on the five calculated N-efficiency indexes, which were higher than or similar to results from M side-dressings or those recorded in the literature. These similarities (M vs. PSs) were also shown by the reduction of unaccounted-for N inside the overall N balance. Thus, split PS application during the crop cycle is a sound fertilization option in dryland systems. 相似文献
7.
Agricultural soil could be made to serve as a sink rather than a source of greenhouse gases by suitable soil management. This study was, therefore, conducted to assess the impact of tillage and fertilizer application on soil and plant carbon and nitrogen fractionation and intrinsic water use efficiency (iWUE). The experiment was a split–split-plot factorial design with three replications. The main plot consisted of two tillage treatments: zero tillage (ZT) and conventional tillage (CT). The sub-plot contained four NPK fertilizer treatments (0, 90, 120 and 150 kg N ha−1), while the sub–sub-plot comprised three poultry manure (PM) treatments (0, 10 and 20 Mg ha−1). Soil carbon and nitrogen sequestration were evaluated using stable isotope of carbon (δ13C) and nitrogen (δ15N). The δ13C in maize plant was used to obtain iWUE. It was observed that soil δ13C and δ15N were more depleted under ZT than CT and in plots treated with 20 Mg ha−1 PM (PM20) implying carbon and nitrogen sequestration under ZT and by PM20. Relative to the control, application of PM20 raised soil δ15N enrichment by 82% and 96% under CT and ZT, respectively. Higher iWUE of 25.7% was obtained under CT and was significantly higher than the iWUE values under ZT in the second year of the study while the iWUE was significantly lower with PM20 application than other fertilizer treatments. The significant δ13C depletion and hence lower iWUE with combination of NPK fertilizer and PM under CT than the control implied that soil disturbance under tilled plots was mediated by combined nutrient management thereby limiting soil C available for fractionation resulting in lower iWUE. This suggests that conservation tillage such as zero tillage and integrated application of organic and inorganic fertilizers are good strategies for reducing soil carbon and nitrogen emission. 相似文献
8.
An experiment was conducted on rice, in old alluvial soil zone, with bio-fertilizer and different doses of organic manure and chemical fertilizer to develop an alternative farming system which is productive, profitable, enhances soil health and conserves the natural resources over a long term. The experiment was conducted for four consecutive years (2007–2010) and it has been observed that 40% N and 25% P chemical fertilizer can safely be supplemented by low-cost, natural resource based bio-fertilizer (Azotobacter sp. and PSB) at 12 kg ha−1 and organic manure (FYM) at 10.00 t ha−1 to achieve long-term sustainability in rice cultivation that is more productive and profitable. 相似文献
9.
In areas of Southern Europe with very intensive pig production, most of the pig slurry (PS) is applied as fertilizer. However, in the European Union, no more than 170 kg N ha−1 year−1 can be applied in nitrate vulnerable zones (NVZs) from livestock manures. In this context, a six-year trial was conducted for a maize-triticale double-annual forage cropping rotation under rainfed conditions. Four different N rates were applied (0, 170, 250 and 330 kg N ha−1 year−1), to evaluate their effect on crop yield, N uptake, unrecovered N and soil nitrate content. The corresponding PS rates were defined as zero (PS 0), low (PSL) medium (PSM) and high (PSH). The annual average dry matter (DM) yields (maize + triticale) for the PS fertilization treatments PS0, PSL, PSM and PSH were 12.6, 17.7, 20.2 and 22.0 Mg DM ha−1, respectively. Maize DM yield was influenced mainly by weather conditions, and triticale DM yield was clearly influenced by initial soil NO3−-N and PS fertilization rates. Unrecovered N was affected by PS fertilization rate and initial soil NO3−-N content. A residual effect of the PS when applied to maize had an important effect on soil NO3−-N and subsequent triticale DM yield. Moreover, total annual average unrecovered N, considering the sum of both crops (maize + triticale), were 91, 144, and 222 kg N ha−1 in PSL, PSM and PSH, respectively. In order to avoid part of this unrecovered N, mainly by lixiviation of nitrates, PS fertilization in triticale should be applied as side dressing at tillering. The application of N, in the form of PS, at rates higher than the legally permitted maximum of 170 kg N ha−1 year−1, may result in better yields. However, high rates of PS fertilization may originate in significantly lower N use efficiency and a higher potential environmental impact in double-cropping systems, practiced in rainfed sub-humid Mediterranean conditions. 相似文献
10.
Root growth, nutrition and crop yield can be affected by soil chemical modifications caused by superficial limestone and phosphogypsum application in a no-till system. Using this approach, this study was conducted in southeastern Brazil, continuing an experiment that has been on-going since 2002 with the objective of evaluating the residual effects of the surface application of lime and phosphogypsum on the soil chemical characteristics and the root growth, nutrition and yield of soybean, black oat and sorghum in a dry winter region cultivated in 2008/2009 and 2009/2010. The experimental design was a randomized block with 4 replications. The treatments were applied in November 2004 and were as follows: original conditions, limestone application (2000 kg ha−1), phosphogypsum application (2100 kg ha−1), and limestone (2000 kg ha−1) + phosphogypsum (2100 kg ha−1) application. Superficial liming with or without phosphogypsum reduced the surface and subsurface soil acidity 5 years after application in the no-till system. The movement of Ca2+ and Mg2+ from the surface layer into the subsoil over time was evident. The phosphogypsum application associated with liming increased the Ca2+ levels throughout the soil profile. Liming maintained high levels of Mg2+ throughout the soil profile with or without phosphogypsum application. The organic matter content increased with liming with or without phosphogypsum, indicating that in the long term, these practices can increase the C accumulation. Phosphogypsum application had a residual effect on the SO4-S levels, and high sulphate concentrations were observed in the subsoil after 5 years. Superficial liming improved crop nutrition and, when associated with phosphogypsum, increased Ca absorption by soybean and sorghum, as reflected in the increased yields of these crops. 相似文献
11.
The sustainability of growing a maize—winter wheat double crop rotation in the North China Plain (NCP) has been questioned due to its high nitrogen (N) fertiliser use and low N use efficiency. This paper presents field data and evaluation and application of the soil–vegetation–atmosphere transfer model Daisy for estimating crop production and nitrate leaching from silty loam fields in the NCP. The main objectives were to: i) calibrate and validate Daisy for the NCP pedo-climate and field management conditions, and ii) use the calibrated model and the field data in a multi-response analyses to optimise the N fertiliser rate for maize and winter wheat under different field managements including straw incorporation.The model sensitivity analysis indicated that a few measurable crop parameters impact the simulated yield, while most of the studied topsoil parameters affect the simulated nitrate leaching. The model evaluation was overall satisfactory, with root mean squared residuals (RMSR) for simulated aboveground biomass and nitrogen content at harvest, monthly evapotranspiration, annual drainage and nitrate leaching out of the root zone of, respectively, 0.9 Mg ha−1, 20 kg N ha−1, 30 mm, 10 mm and 10 kg N ha−1 for the calibration, and 1.2 Mg ha−1, 26 kg N ha−1, 38 mm, 14 mm and 17 kg N ha−1 for the validation. The values of mean absolute deviation, model efficiency and determination coefficient were also overall satisfactory, except for soil water dynamics, where the model was often found erratic. Re-validation run showed that the calibrated Daisy model was able to simulate long-term dynamics of crop grain yield and topsoil carbon content in a silty loam field in the NCP well, with respective RMSR of 1.7 and 1.6 Mg ha−1. The analyses of the model and the field results showed that quadratic, Mitscherlich and linear-plateau statistical models may estimate different economic optimal N rates, underlining the importance of model choice for response analyses to avoid excess use of N fertiliser. The analyses further showed that an annual fertiliser rate of about 300 kg N ha−1 (100 for maize and 200 for wheat) for the double crop rotation with straw incorporation is the most optimal in balancing crop production and nitrate leaching under the studied conditions, given the soil replenishment with N from straw mineralisation, atmospheric deposition and residual fertiliser.This work provides a sound reference for determining N fertiliser rates that are agro-environmentally optimal for similar and other cropping systems and regions in China and extends the application of the Daisy model to the analyses of complex agro-ecosystems and management practices under semi-arid climate. 相似文献
12.
Biomass productivity, nitrogen recovery fraction and nitrogen utilization efficiency (NUE) of kenaf (Hibiscus cannabinus L.) cultivar Tainung 2 were tested, under three Lens culinaries treatments (incorporated, harvested before the sowing of the energy crop and mono-cropping) and four nitrogen dressings (0, 50, 100 and 150 kg ha−1), in two field experiments carried out on a fertile, clayey to loamy soil, and on a sandy soil of moderate fertility, in central Greece, over the period 2007–2009. The obtained results showed a positive response in L. culinaries cover cropping on kenaf total yield, on both experimental sites. Total dry biomass fluctuated from 16.07 to 21.46 t ha−1 for incorporated plots and from 13.63 to 16.55 t ha−1 for control treatments (relied only on applications of N-fertilization) for sandy soil, and from 14.98 to 19.28 t ha−1 in case of legume incorporation and from 12.34 to 16.69 t ha−1 for control plots, for clayey soil, respectively. The evaluated NUE was 76 kg kg−1, for sandy soil, and 72 kg kg−1, for clay soil. The recovery fraction escalated from 41% in control plots to 70% in plots with previous L. culinaries cultivation for sandy soil, while for clayey soil an increase of 20% was recorded, indicating a prominent effect of legume cover-cropping management. 相似文献
13.
The expansion of biogas production from anaerobic digestion in the Po Valley (Northern Italy) has stimulated the cultivation of dedicated biomass crops, and maize in particular. A mid-term experiment was carried out from 2006 to 2010 on a silt loamy soil in Northern Italy to compare water use and energy efficiency of maize and sorghum cultivation under rain fed and well-watered treatments and at two rates of nitrogen fertilization. The present work hypothesis were: (i) biomass sorghum, for its efficient use of water and nitrogen, could be a valuable alternative to maize for biogas production; (ii) reduction of irrigation level and (iii) application of low nitrogen fertilizer rate increase the efficiency of bioenergy production. Water treatments, a rain fed control (I0) and two irrigation levels (I1 and I2; only one in 2006 and 2009), were compared in a split–split plot design with four replicates. Two fertilizer rates were also tested: low (N1, 60 kg ha−1 of nitrogen; 0 kg ha−1 of nitrogen in 2010) and high (N2, 120 kg ha−1 of nitrogen; 100 kg ha−1 of nitrogen in 2010). Across treatments, sorghum produced more aboveground biomass than maize, respectively 21.6 Mg ha−1 and 16.8 Mg ha−1 (p < 0.01). In both species, biomass yield was lower in I0 than in I1 and I2 (p < 0.01), while I1 and I2 did differ significantly. Nitrogen level never affected biomass yield. Water use efficiency was generally higher in sorghum (52 kg ha−1 mm−1) than in maize (38 kg ha−1 mm−1); the significant interaction between crop and irrigation revealed that water use efficiency did not differ across water levels in sorghum, whereas it significantly increased from I0 and I1 to I2 in maize (p < 0.01). The potential methane production was similar in maize and sorghum, while it was significantly lower in I0 (16505 MJ ha−1) than in I1 and I2 (21700 MJ ha−1). The only significant effect of nitrogen fertilization was found in the calculation of energy efficiency (ratio of energy output and input) that was higher in N1 than in N2 (p < 0.01). These results support the hypothesis that (i) sorghum should be cultivated rather than maize to increase energy efficiency, (ii) irrigation level should replace up to 36% of ETr and (iii) nitrogen fertilizer rate should be minimized to maximize the efficiency in biomass production for anaerobic digestion in the Po Valley. 相似文献
14.
《European Journal of Agronomy》2000,12(1):37-54
APSIM Nwheat is a crop system simulation model, consisting of modules that incorporate aspects of soil water, nitrogen (N), crop residues, and crop growth and development. The model was applied to simulate above- and below-ground growth, grain yield, water and N uptake, and soil water and soil N of wheat crops in the Netherlands. Model outputs were compared with detailed measurements of field experiments from three locations with two different soil types. The experiments covered two seasons and a range of N-fertiliser applications. The overall APSIM Nwheat model simulations of soil mineral N, N uptake, shoot growth, phenology, kernels m−2, specific grain weight and grain N were acceptable. Grain yields (dry weight) and grain protein concentrations were well simulated with a root mean square deviation (RMSD) of 0.8 t ha−1 and 1.6 protein%, respectively. Additionally, the model simulations were compared with grain yields from a long-term winter wheat experiment with different N applications, two additional N experiments and regional grain yield records. The model reproduced the general effects of N treatments on yields. Simulations showed a good consistency with the higher yields of the long-term experiment, but overpredicted the lower yields. Simulations and earlier regional yields differed, but they showed uniformity for the last decade.In a simulation experiment, the APSIM Nwheat model was used with historical weather data to study the relationship between rate and timing of N fertiliser and grain yield, grain protein and soil residual N. A median grain yield of 4.5 t ha−1 was achieved without applying fertiliser, utilising mineral soil N from previous seasons, from mineralisation and N deposition. Application of N fertiliser in February to increase soil mineral N to 140 kg N ha−1 improved the median yield to 7.8 t ha−1 but had little effect on grain protein concentration with a range of 8–10%. Nitrogen applications at tillering and the beginning of stem elongation further increased grain yield and in particular grain protein, but did not affect soil residual N, except in a year with low rainfall during stem elongation. A late N application at flag leaf stage increased grain protein content by several per cent. This increase had only a small effect on grain yield and did not increase soil residual N with up to 40 kg N ha−1 applied, except when N uptake was limited by low rainfall in the period after the flag leaf stage. The economic and environmental optima in winter wheat were identified with up to 140 kg N ha−1 in February, 90 kg N ha−1 between tillering and beginning of stem elongation and 40 kg N ha−1 at flag leaf stage resulting in a median of 8.5 t ha−1 grain yield, 14.0% grain protein and 13 kg N ha−1 soil residual N after the harvest. The maximum simulated yield with maximum N input from two locations in the Netherlands was 9.9 t ha−1. 相似文献
15.
In the context of deteriorating soil health, stagnation of yield in rice-wheat cropping system (RWCS) across Indo- Gangetic plains (IGP) and environmental pollution, a long term field experiment was conducted during 2009–2016 taking four crop scenarios with conservation agriculture (CA), crop intensification and diversified cropping as intervening technology aiming to evaluate the sustainability of the systems. Scenario 1 (S1) represented conventional farmers’ practice of growing rice and wheat with summer fallow. In scenario 2 (S2) and scenario 3 (S3), legume crop was taken along with rice and wheat with partial CA and full CA, respectively. Conventional RWCS was replaced with rice-potato + maize- cowpea cropping system with partial CA in scenario 4 (S4). The S3 scenario registered highest total organic carbon (TOC) stock of 47.71 Mg C ha−1 and resulted in significant increase of 14.57% over S1 (Farmer’s practice) in 0–30 cm soil depth after 7 years of field trial. The S4 scenario having intensified cropping systems recorded lowest TOC of 39.33 Mg C ha−1 and resulted in significant depletion of 17.56% in C stock with respect to S3 in 0–30 cm soil depth. The TOC enrichment was higher in S2, S3 and S4 scenario in the surface soil (0–10 cm) compared to S1. At lower depth (20–30 cm), the TOC enrichment was significantly higher in S2 (12.82 Mg C ha−1) and S3 (13.10 Mg C ha−1 soil) over S1 scenario. The S2 and S3 scenario recorded highest increased allocation of TOC (3.55 and 6.13 Mg C ha−1) to passive pool over S1. The S2 (15.72 t ha−1), S3 (16.08 t ha−1) and S4 (16.39 t ha−1) scenarios recorded significantly higher system rice equivalent yield over S1 (10.30 t ha−1). Among the scenarios, S3 scenario had greater amount of total soil organic carbon, passive pool of carbon and higher system rice equivalent yield, thus, is considered the best cropping management practice to maintain soil health and food security in the middle IGP. 相似文献
16.
Integrated no-till crop and livestock production systems may help rejuvenate degraded pastures, increase land use efficiency (LUE), and increase enterprise revenue. Our objectives were to evaluate: (1) planting date effects on seed yield and nutrient concentration of an early-maturing, no-till system (NTS) soybean (Glycine max) when intercropped with palisade grass (Brachiaria brizantha); (2) dry matter production and protein concentration of the grass pasture after soybean harvest; and (3) overall revenue and LUE for the intercrop system. Experiments were performed during two growing seasons in Botucatu, Brazil using a randomized complete block experimental design. When palisade grass and soybean were sown simultaneously, soybean yield averaged 3.28 Mg ha−1. Similar seed yields were observed when palisade grass was planted either 30 d after soybean emergence (DAE) (3.29 Mg ha−1) or at the soybean reproductive stage R6 (full seed) (3.50 Mg ha−1). Monocrop soybean yield averaged 3.50 Mg ha−1. First cut dry matter forage production was greater when palisade grass was sown at the same time as soybean or 30 DAE of soybean. This indicates that interseeding palisade grass with soybean does not significantly affect soybean nutrition or yield. Intercropping did increase LUE and resulted in 1.6 times more revenue than soybean alone. However, sowing palisade grass at the soybean reproductive stage R6 (full seed) significantly reduced the forage yield compared to early planting. 相似文献
17.
In this study, we report efficiencies of light capture and biomass yield of festulolium and tall fescue cultivated on a riparian fen in Denmark under different harvesting managements. Green biomass targeted for biogas production was harvested either as two cuts (2C) or three cuts (3C) in a year. Three different timings of the first cut in the 2C systems were included as early (2C-early), middle (2C-mid) and late (2C-late) cuts corresponding to pre-heading, inflorescence emergence and flowering stages, respectively. The fraction of intercepted photosynthetically active radiation (fPAR) was derived from the canopy reflectance measured on 61 dates throughout a year, and cumulative interception of PAR (IPAR) and radiation use efficiency (RUE) was calculated. The dynamics of fPAR and biomass accumulations was similar for both crops before the first cuts in all managements. Festulolium fPAR in 2C-early and 2C-mid managements declined faster than in 2C-late and 3C managements in the second growth period and thus growing period IPAR of 2C-early and 2C-mid declined by 8% as compared to 3C management where IPAR was 925 MJ m−2. Annual festulolium dry matter (DM) yield in 2C-early and 2C-mid managements (average 14.1 Mg DM ha−1) decreased by 22% compared to 3C management (18.2 Mg DM ha−1). The highest and the lowest RUE of festulolium were observed in 3C and 2C-mid managements as 1.97 and 1.59 g MJ−1, respectively. For tall fescue fPAR declined rather slowly in the second growing period in all 2C managements, which contributed to similar IPAR (908–919 MJ m−2), total biomass yield (16.4–18.8 Mg DM ha−1 yr−1) and RUE (1.80–2.07 g MJ−1) for all managements. Whereas both crops were highly productive under both 3C management and 2C management with first harvest after flowering (i.e., 2C-late), the 2C-late strategy is recommended as the least intensive of the two management systems. 相似文献
18.
Poor soil and drought stress are common in semiarid areas of China, but maize has a high demand for nitrogen (N) and water. Maize production using the technique of double ridges and furrows mulched with plastic film are being rapidly adopted due to significant increases in yield and water use efficiency (WUE) in these areas. This paper studied N use and water balance of maize crops under double ridges and furrows mulched with plastic-film systems in a semiarid environment over four growing seasons from 2007 to 2010. To improve precipitation storage in the non-growing season, the whole-year plastic-film mulching technique was used. There were six treatments which had 0, 70, 140, 280, 420 or 560 kg N ha−1 applied in every year for maize. In April 2011, spring wheat was planted in flat plots without fertilizer or mulch following four years of maize cultivation. After four years, all treatments not only maintained soil water balance in the 0–200 cm soil layer but soil water content also increased in the 0–160 cm soil layer compared to values before maize sowing in April 2007. However, under similar precipitation and only one season of spring wheat, soil water content in the 0–160 cm soil layer sharply decreased in all treatments compared to values before sowing in April 2011. Over the four years of maize cultivation, average yield in all treatments ranged from 4071 to 6676 kg ha−1 and WUE ranged from 18.2 to 28.2 kg ha−1 mm−1. In 2011, the yield of spring wheat in all treatments ranged from 763 to 1260 kg ha−1 and WUE from 3.5 to 6.5 kg ha−1 mm−1. The potential maximum grain yield for maize was 6784 kg ha−1 with 360 kg N ha−1 applied for four years, but considerable NO3N accumulated in the soil profile. A lesser application (110 kg N ha−1) to this tillage system yielded in 82% of the maximum, increased nitrogen use efficiency and mitigated the risk of nitrogen loss from the system. This study suggests that double ridge–furrow and whole-year plastic-film mulching could sustain high grain yields in maize with approximately 110 kg N ha−1 and maintain soil water balance when annual precipitation is >273 mm in this semiarid environment. 相似文献
19.
The effect of succeeding crop and level of N fertilization on N leaching after break-up of grassland
《European Journal of Agronomy》2009,30(4):200-207
Depending on soil and management, ploughing up grassland for use as arable land can lead to an increase in the release of mineralized nitrogen and a high risk of nitrogen leaching during winter. The amount of N leaching is also dependent on the N efficiency of following crops and the level of N fertilization.In a field experiment in northwest Germany permanent grassland was ploughed and used as arable land. The experiment was conducted over 2 years at three sites and investigated two main factors: (i) succeeding crops, either spring barley (and catch crop)–maize or silage maize–maize; and (ii) N-fertilization either nil or moderate (120 kg N ha−1 for barley or 160 kg for maize). Plant yields, the soil mineral nitrogen (SMN) content and the nitrate leaching losses over winter were determined. On average for the 2-year period, the SMN in autumn and the nitrate leaching losses during winter for the rotation barley–maize were 76 kg ha−1 SMN and 81 kg N ha−1 N leaching losses, and for maize–maize they amounted to 108 and 113 kg ha−1, respectively. The SMN and N leaching losses for the plots with no N fertilizer were 49 and 52 kg N ha−1 and for the plots fertilized at a moderate N level they were 135 and 142 kg N ha−1, respectively.We conclude that although the extent of nitrate leaching is influenced by the site conditions and management of the grassland prior to ploughing, the management after ploughing is the decisive factor. The farmer can significantly reduce nitrate leaching with his choice of succeeding crop and the amount of N fertilization. 相似文献
20.
《European Journal of Agronomy》2007,26(2):166-177
In Jiangsu province, Southeast China, high irrigated rice yields (6–8000 kg ha−1) are supported by high nitrogen (N) fertilizer inputs (260–300 kg N ha−1) and low fertilizer N use efficiencies (recoveries of 30–35%). Improvement of fertilizer N use efficiency can increase farmers’ profitability and reduce negative environmental externalities. This paper combines field experimentation with simulation modeling to explore N fertilizer management strategies to realize high yields, while increasing N use efficiency. The rice growth model ORYZA2000 was parameterized and evaluated using data from field experiments carried out in Nanjing, China. ORYZA2000 satisfactorily simulated yield, crop biomass and crop N dynamics, and the model was applied to explore options for different N-fertilizer management regimes, at low and high levels of indigenous soil N supply, using 43 years of historical weather data.On average, yields of around 10–11,000 kg ha−1 were realized (simulated and in field experiments) with fertilizer N rates of around 200 kg ha−1. Higher fertilizer doses did not result in substantially higher yields, except under very favorable weather conditions when yields exceeding 13,000 kg ha−1 were calculated. At fertilizer rates of 150–200 kg ha−1, and at the tested indigenous soil N supplies of 0.6–0.9 kg ha−1 day−1, high fertilizer N recovery (53–56%), partial N productivity (50–70 kg kg−1) and agronomic N use efficiency (20–30 kg kg−1) were obtained with application in three equal splits at transplanting, panicle initiation and booting. Increasing the number of splits to six did not further increase yield or improve any of the N use efficiency parameters. 相似文献