The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds...The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds (PRB) systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical (powered-chopper, powered-cutter and powered-disc) PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better (non-significant) than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.展开更多
In Japan, common wheat is cultivated in upland fields converted from paddy fields, where poor drainage and high precipitation cause delay of sowing, lodging at the jointing stage, difficulty in topdressing at the ripe...In Japan, common wheat is cultivated in upland fields converted from paddy fields, where poor drainage and high precipitation cause delay of sowing, lodging at the jointing stage, difficulty in topdressing at the ripening stage, and low yield. No-till cultivation has been promoted to overcome these problems but the yield is still low due to the lack of proper fertilizer application protocols. In this study, we determined whether an additional application of two kinds of Sigmoid coated urea as controlled availability fertilizers (CAFs) to the standard fertilization protocol for tillage cultivation can increase the yield and lodging resistance in no-till cultivated common wheat. Also, additional fertilization was applied to the seeding furrow simultaneously with seeding using a V-furrow no-till direct sowing (VFDS) machine. No-till cultivated plants had more tillers than tillage cultivated ones and consequently higher number of panicles and yield, caused by increased fertilizer application. The point-injected CAFs to the seeding furrow, which eluted at the jointing and ripening stages greatly increased the grain yield and protein content, respectively, compared to broadcast topdressing of ammonium sulfate at each stage. The simultaneous sowing and fertilization of additional CAFs using VFDS method in multi-year tests in farmers’ fields significantly increased the yield of no-till cultivated common wheat, and can be adopted by Japanese local farmers.展开更多
The common practice of establishing rice in the rice-wheat system in India is manual transplanting of seedlings in the puddled soil. Besides being costly, cumbersome, and time consuming, puddling results in degradatio...The common practice of establishing rice in the rice-wheat system in India is manual transplanting of seedlings in the puddled soil. Besides being costly, cumbersome, and time consuming, puddling results in degradation of soil and the formation of a hard pan, which impedes root growth of subsequent upland crops. In addition, decreased availability and increasing cost of labor have increased the cost of rice cultivation through conventional methods. Because of these concerns, there is a need for mechanized transplanting of rice which is less labor-intensive and can ensure optimum plant population under nonpuddled and/or no-till conditions. A large number of on-farm trials were conducted at farmers’ fields in Haryana, India, from 2006 to 2010 to evaluate the performance of the mechanical transplanted rice (MTR) under nonpuddled and no-till situations as compared to conventional puddled transplant rice (CPTR). Compared with CPTR, nonpuddled MTR produced 3%-11% higher grain yield in different years. Rice cultivars, viz. HKR47, HKR127, PR113, PR114, PB1, PB1121, CSR30, and Arize6129, performed consistently better under nonpuddled MTR as compared to CPTR. Performance of different cultivars (PR113, PR114, HKR47, and Pusa 44) was also better under no-till MTR as compared to CPTR. The “basmati” cultivar CSR30 performed equally in no-till MTR and CPTR systems. The results of our study suggest that rice can be easily grown under nonpuddled and no-till conditions with yield advantages over the CPTR system. Even in the case of similar yield between CPTR and MTR systems, the MTR system will help in reducing labor requirement and ultimately, will increase overall profits to farmers.展开更多
Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption...Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption,dust raising and interference from intertwined straw.In view of this,in this study,a driving roller dibbling-type no-till seeding and hole-forming(DGR-NT-SHF)system was designed to be capable of penetrating soil and creating holes without requiring any special preparation of the surface covering.The core mechanism of this system consisted of a land wheel-driven driving roller and a duckbill-type roller seeder,which were internally tangent to one another.The rotating roller rolled the straw into a thin layer,and the duckbills extended from the roller and penetrated this thin layer of straw and subsequently formed the holes and planted the seeds.Based on kinematic analysis,a mathematical model was established to depict the relations between the rear angle of the duckbill(α),the front angle of the duckbill(β),the angular velocity of the duckbill-type roller seeder(ω0),the angular velocity of the roller(ω1),and the aperture of the duckbill outlet on the roller(θ).In contrast to a driven roller-type no-till seeding and hole-forming DNR-NT-SHF system,several parameters of the DGR-NT-SHF system were established for planting seeds at a plant spacing that was an integral multiple of 100 mm:the radius of the duckbill-type roller seeder,200 mm;radius of the roller,400 mm;α,23°;andβ,5°.Based on the analysis of the models using the MATLAB Image Processing Module with a relation betweenω1 and the number of outlets on the roller as the constraint,the optimal number of outlets on the roller and theω1/ω0 ratio were determined to be 21 and 4/7,respectively.Kinematic simulation on a digital prototype was performed using computer aided three-dimensional interactive application(CATIA)to observe the motion of the DGR-NT-SHF system,when the duckbills on the duckbill-type roller seeder were open and to determine the locations of the duckbills relative to the outlets.To ensure the duckbills could be successfully opened,the chord length of the outlets was ultimately determined to be 71 mm.The prototype test results showed that the DGR-NT-SHF system met the design requirements and that the operation was straightforward and reliable.In addition,compared to the DNR-NT-SHF system,the DGR-NT-SHF system performed better in penetration and exerted no impact on the duckbills,thus providing an effective technical option for no-till seeding.展开更多
Strawponic is an innovative and exotic system for growing potato on soil surface using crop straw as cover mulch. A field trial was carried out at the American University of Beirut in Lebanon to test the efficacy of t...Strawponic is an innovative and exotic system for growing potato on soil surface using crop straw as cover mulch. A field trial was carried out at the American University of Beirut in Lebanon to test the efficacy of this system for small potato producers. Barley (Hordeum vulgare) straw mulch at 25, 50 and 75 t/ha was used to cover potato tubers in no-till system. Potato plant number, height, number of shoots and leaves, root and shoot dry weight, and potato yield were collected. Results showed that all tested rates of straw significantly increased potato yield in comparison to the till system. Marketable yield was the highest with no-till potato at 50 and 75 t/ha compared to no-till potato at all tested surface straw rates. None of the treatments was harmful to potato plants compared to the till potato. This study could be a promising gate for production of potato for small-scale farmers.展开更多
Global food demand requires that soils be used intensively for agriculture, but how these soils are managed greatly impacts soil fluxes of carbon dioxide (CO2). Soil management practices can cause carbon to be either ...Global food demand requires that soils be used intensively for agriculture, but how these soils are managed greatly impacts soil fluxes of carbon dioxide (CO2). Soil management practices can cause carbon to be either sequestered or emitted, with corresponding uncertain influence on atmospheric CO2 concentrations. The situation is further complicated by the lack of CO2 flux measurements for African subsistence farms. For widespread application in remote areas, a simple experimental methodology is desired. As a first step, the present study investigated the use of Bowen Ratio Energy Balance (BREB) instrumentation to measure the energy balance and CO2 fluxes of two contrasting crop management systems, till and no-till, in the lowlands within the mountains of Lesotho. Two BREB micrometeorological systems were established on 100-m by 100-m sites, both planted with maize (Zea mays) but under either conventional (plow, disk-disk) or no-till soil mangement systems. The results demonstrate that with careful maintenance of the instruments by appropriately trained local personnel, the BREB approach offers substantial benefits in measuring real time changes in agroecosystem CO2 flux. The periods where the two treatments could be compared indicated greater CO2 sequestration over the no-till treatments during both the growing and non-growing seasons.展开更多
To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method w...To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was designed.Through simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was adopted.According to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and consistent.The standard error of the slope of the fitting equation of the downforce calculation model is 0.008.According to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,respectively.The coefficients of variation were 0.40,0.41,0.62,and 0.71,respectively.The results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting speed.Both the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.展开更多
Whether biochar produced as a by-product of energy generation from the papermill industry,and often disposed in landfills,can be gainfully applied to commercial croplands has not been investigated.The objective of thi...Whether biochar produced as a by-product of energy generation from the papermill industry,and often disposed in landfills,can be gainfully applied to commercial croplands has not been investigated.The objective of this study was to investigate the physical and hydraulic properties of soils in commercial cotton fields managed as no-till systems following repeated applications of biochar generated as a waste of a papermill plant.Undisturbed cores and disturbed soil samples were collected from 0-5 and 5-10 cm layers from five commercial no-till fields in Mississippi,USA that received 6.7 Mg ha^(−1) year^(−1) biochar for 0,2,3,5 or 10 years.A number of physical,hydraulic,and chemical properties of these samples were measured in the lab.The results showed that biochar reduced the degree of soil compactness and increased soil aggregation and structural stability index.The findings were particularly apparent for the 10 years of consecutive application,which increased soil aggregate stability by up to 67%,reduced bulk density from 1.40 to 1.26 g cm^(−3),and reduced degree of compactness from 73.2%to 62.8%.Biochar increased soil porosity but much of this increase(55%)occurred for small pores(<0.5μm)with little effect on storage pores(0.5-50μm)or transmission pores(>50μm).Consequently,biochar increased soil field capacity by up to 26%,but PAW increased by only 17%.Biochar significantly increased soil physical quality index score in the 0-5 cm layer from 0.16 to 0.26 and the increase was positively correlated with the number of years of application.The results suggest biochar generated as a byproduct of papermill could be land-applied in real-world crop production systems to improve soil health as an alternative to disposal in landfills.展开更多
An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistenc...An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%.展开更多
Aiming at the problems of uneven plant spacing,row spacing and sowing depth due to the collision of seeds with the tube wall or bouncing on the floor of the seed guide tube with the increase of operation speed of the ...Aiming at the problems of uneven plant spacing,row spacing and sowing depth due to the collision of seeds with the tube wall or bouncing on the floor of the seed guide tube with the increase of operation speed of the current corn no-till planter,in this study,the high-speed seed belt technology was combined with the finger clip seed discharge device,a kind of high-speed no-till planter monomer was designed and installed in high-speed seed tube.At the same time,simulation analysis was made on the movement law of seeds in the seed guide tube when they fell from the finger clip seeder and the main structural parameters and the range of key parameters of the high-speed seed tube were determined.Through the prototype,the single-factor and quadratic orthogonal rotational combination test method,and the machine operating speed,the height of the high-speed seed tube and the seed guide angle were selected as the test factors in the seeding performance test.After parameter optimization,the optimal working parameters were determined:the machine forward speed was 12.18 km/h,the height of the high-speed seed tube from the ground was 42.22 mm,and the seed guide angle of the high-speed seed tube was 8.82°.The field test verified that under this parameter combination,the qualified-seeding index was 94.95%,the multiple-seeding index was 2.37%,and the missing-seeding index was 2.48%,showing stable working performance and satisfied the sowing and agronomic requirements of the no-till seeding operation.展开更多
The aim of this study was to evaluate the physiological quality and seed production of Fabaceae and corn in monoculture and intercropping in areas cropped under different management. The following treatments were eval...The aim of this study was to evaluate the physiological quality and seed production of Fabaceae and corn in monoculture and intercropping in areas cropped under different management. The following treatments were evaluated: corn + NPK + weed control;corn + weed control;corn + NPK;corn + crotalaria;corn + jack bean. Intercropping raised the average number of corn ears of corn and the seed IVG Weed control positively influenced the final stand and average number of ears. NPK fertilization on corn sowing positively influenced the seed electrical conductivity. The yield of corn plants intercropped with crotalaria and jack bean was statistically similar. However, their absolute values should be considered for economic purposes. Corn seeds derived from intercropping with crotalaria were more effective compared with intercropping with jack bean. Crotalaria and jack bean seeds when intercropped with corn have high production, germination and vigor (IVG and emergence).展开更多
Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation til...Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation tillage research, this paper discusses the long-term effect of conservation tillage on sustainable land use, nutrient availability and crop yield response. Research has shown several potential benefits associated with conservation tillage, such as potential carbon sequestration, nutrient availability, and yield response. This research would provide a better perspective of the role of soil conservation tillage and hold promise in promoting application of practical technologies for dryland farming systems in China.展开更多
In 1999 no-tillage farming,synonymous of zero tillage farming or conservation agriculture,was adopted on about 45 million ha world wide,growing to 72 million ha in 2003 and to 111 million ha in 2009,corresponding to a...In 1999 no-tillage farming,synonymous of zero tillage farming or conservation agriculture,was adopted on about 45 million ha world wide,growing to 72 million ha in 2003 and to 111 million ha in 2009,corresponding to an growth rate of 6 million ha per annum.Fastest adoption rates have been experienced in South America where some countries are using no-tillage farming on about 70%of the total cultivated area.Opposite to countries like the USA where often fields under no-tillage farming are tilled every now and then,more than two thirds of the area under no-tillage systems in South America is permanently not tilled;in other words once adopted,the soil is never tilled again.The spread of no-tillage systems on more than 110 million ha world-wide shows the great adaptability of the systems to all kinds of climates,soils and cropping conditions.No-tillage is now being practiced from the artic circle over the tropics to about 50ºlatitude south,from sea level to 3,000 m altitude,from extremely rainy areas with 2,500 mm a year to extremely dry conditions with 250 mm a year.No-till farming offers a way of optimizing productivity and ecosystem services,offering a wide range of economic,environmental and social benefits to the producer and to the society.At the same time,no-till farming is enabling agriculture to respond to some of the global challenges associated with climate change,land and environmental degradation,and increasing cost of food,energy and production inputs.The wide recognition of no-till farming as a truly sustainable system should ensure the spread of the no-till technology and the associated practices of organic soil cover and crop rotation,as soon as the barriers to its adoption have been overcome,to areas where adoption is currently still low.The widespread adoption globally also shows that no-tillage farming cannot any more be considered a temporary fashion or a craze;instead largely through farmers’own effort,the system has established itself as a farming practice and a different way of thinking about sustainable agro-ecosystem management that can no longer be ignored by scientists,academics,extension workers,farmers at large as well as equipment and machine manufacturers and politicians.展开更多
Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture ...Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture (CA) is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world's arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.展开更多
The benefits of conservation agriculture(CA)have been widely recognized and CA has been widely adopted in many parts of the world.However,there are some factors that limit the widespread adoption of CA in Asia.The mos...The benefits of conservation agriculture(CA)have been widely recognized and CA has been widely adopted in many parts of the world.However,there are some factors that limit the widespread adoption of CA in Asia.The most prominent factor appears to be the lack of suitable CA seeders for small to medium sized land-holding(SLH)farmers.This paper summarizes the small to medium no-till and minimum-till seeders currently available in Asia,and classifies these seeders into four types:manually operated units,animal traction seeders,two-wheel tractor and four-wheel tractor driven seeders.Detailed characteristics have been provided for some typical CA seeders and comparisons were made as to their suitability under particular working conditions.Typically manual and animal traction seeders are confined to small farms and hilly areas,while the larger CA seeders suited to four-wheel tractors are used on larger acreages.To ensure seeding performance on most four-wheel tractor CA seeders,two types of anti-blocking mechanisms(passive and active anti-blocking)have been fitted.Finally,the paper proposes a future direction and development of CA seeders for small/medium size farms in Asia,and also suggests changes in policy support,improvement of anti-blocking mechanisms,suitability for various crops,geographical zones and the contribution of development by public private partnerships to advance the adoption of CA seeders.展开更多
In the continuous annual wheat-corn cropping area of North China Plain,no-till planting that promotes soil conservation and crop yield while reducing operation cost has been gradually accepted by local farmers.However...In the continuous annual wheat-corn cropping area of North China Plain,no-till planting that promotes soil conservation and crop yield while reducing operation cost has been gradually accepted by local farmers.However,previous wheat residue is the main limiting factor affecting the performance of existing planters in placing seeds at uniform spacing and optimum depth in residue covered fields.In order to solve this problem,a kind of ground-wheel-driven row cleaner was designed,developed and mounted on row units of a four-row pneumatic precision planter.The planter has two adjacent row units equipped with the newly designed row cleaners and the other two adjacent row units equipped with the commonly used inactive row cleaners.This was used for planting at three forward speeds(4 km/h,6 km/h and 8 km/h)into half residue(HR)and whole residue(WR)plots.The amount of residue removal,seeding depth,emergence rate and indices of uniformity in seed spacing(missing-seeding index,quality of feeding index and precision index)were measured.The newly designed row cleaner performed better with regard to residue removal,with the average percentage of residue cleared as 63.0%compared to 40.3%for the inactive row cleaner.For the HR and WR plots,percentage of residue cleared of the newly designed row cleaner reached 57.1%and 68.9%respectively,suggesting that the newly designed row cleaner can work more effectively at high residue level.By contrast,with the percentage of residue cleared of the inactive row cleaner as 43.1%and 37.5%in HR and WR plots,suggesting that the inactive row cleaner just can work effectively under low residue condition.Values of missing-seeding index,QFI,precision index,coefficient of variation of depth and percent emergence for the newly designed row cleaner under whole residue level are comparable to those for the inactive row cleaner under half residue level.The result indicates that the effect of using the newly designed row cleaner is equal to that of reducing surface residue,and can help to maintain the uniformity of seed spacing and seeding depth.The newly designed row cleaner generally performed better at forward speed of 6 km/h,based on the distribution of seeds along rows and seeding depth uniformity.展开更多
No-till planters are very popular for maize seeding in fields covered with residue in annual wheat-maize double cropping system in North China Plain.However,there is no suitable depth control mechanism for existing no...No-till planters are very popular for maize seeding in fields covered with residue in annual wheat-maize double cropping system in North China Plain.However,there is no suitable depth control mechanism for existing no-till maize planters,and as a result,it is hard to obtain consistent planting depth,uniform emergence,and good passing ability at the same time.For the above reasons,a proper planting unit with a new type of depth-control mechanism was developed in this study.The mechanism consists of a single-side gauge wheel,a parallel four-bar linkage,a pair of double-disc opener,a V-shape press wheel and a depth regulator,which can adjust the planting depth from 30 mm to 90 mm to satisfy the agronomic requirement under different field conditions.Based on analysis and calculation,the width of gauge wheel was set to 50 mm while the length of parallel four-bar linkage was set to 350 mm.Field experiment was conducted and the results indicated that the newly designed planting unit with single-side gauge wheel performed well with regard to planting depth uniformity and anti-blocking ability.The planting depth uniformity and seed spacing quality were 95.45%and 91.90%,respectively,when the average height of stubble was 22.5 cm and residue amount was 0.64 kg/m^(2)in the field.It can satisfy the requirement of no-till maize planting on the cropland with residue and stubble in North China Plain.展开更多
The U.S. Farm Bill includes conservation practices that benefit both the environment and the farmer. The USDA Conservation Effects Assessment Project (CEAP) is a multi-agency effort to assess the efficiency of conserv...The U.S. Farm Bill includes conservation practices that benefit both the environment and the farmer. The USDA Conservation Effects Assessment Project (CEAP) is a multi-agency effort to assess the efficiency of conservation practices to minimize non-point source pollution. This is follow-up study of a 28-year experiment design to assess the influence of the conservation practices of no-till and crop rotation systems (corn [Zea mays]-soybean [Glycine max]), compared to chisel tillage and monocropping systems (continuous corn) on soil health and water quality. In this study, changes on soil C and N, soil water content, runoff, and losses of ammonium-N, nitrate-N, soluble reactive P (SRP), atrazine, metolachlor, and glyphosate were compared to determine the influence of no-till and corn-soybean rotation systems, relative to chisel tillage and continuous corn, on plots planted with corn using variable intensity rainfall simulations. The long-term no-till systems had a positive impact on soil C and N, soil water, runoff, and losses of ammonium-N and nitrate-N;however, no effect was observed on losses of SRP, atrazine, metolachlor, and glyphosate. The corn-soybean rotation negatively influenced, compared to the continuous corn, soil C and N, soil water content, and increased runoff and the losses of all nutrients and herbicides measured in this study. These results suggest that additional conservation practices, in conjunction with no-till and corn-soybean rotations are needed to reduce surface losses of nutrients and pesticides while improving soil health.展开更多
Sowing depth has an important impact on the performance of no-tillage planters,it is one of the key factors to ensure rapid germination.However,the consistency of sowing depth is easily affected by the complex environ...Sowing depth has an important impact on the performance of no-tillage planters,it is one of the key factors to ensure rapid germination.However,the consistency of sowing depth is easily affected by the complex environment of no-tillage operation.In order to improve the performance of no-tillage planters and improve the control precision of sowing depth,an intelligent depth regulation system was designed.Three Flex sensors installed on the inner surface of the gauge wheel at 120°intervals were used to monitor the downward force exerted by the seeding row unit against ground.The peak value of the output voltage of the sensor increased linearly with the increase of the downward force.In addition,the pneumatic spring was used as a downforce generator,and its intelligent regulation model was established by the Mamdani fuzzy algorithm,which can realize the control of the downward force exerted by the seeding row unit against ground and ensure the proper seeding depth.The working process was simulated based on MATLAB-Simulink,and the results showed that the Mamdani fuzzy model performed well in changing the pressure against ground.Field results showed that when the operating speed was 6 km/h,8 km/h and 10 km/h,the error of the system’s control of sowing depth was±9 mm,±12 mm,and±22 mm,respectively,and its sowing performance was significantly higher than that of the unadjusted passive operation.展开更多
Traditional agriculture bases most of its operations or practices on soil tillage,which causes likely occurrence of water and soil erosion and sediment runoff.In order to conserve soil,water and environment,Conservati...Traditional agriculture bases most of its operations or practices on soil tillage,which causes likely occurrence of water and soil erosion and sediment runoff.In order to conserve soil,water and environment,Conservation agriculture(CA)is increasingly adopted to replace traditional tillage agriculture to achieve sustainable and profitable agriculture and subsequently improve the livelihoods of farmers.CA holds great potential for all sizes of farms and agro-ecological systems,but its adoption is most urgently required by smallholder farmers,especially those short of laborers.Small/medium size no-till machines and implements are the key to CA adoption.A review article on small/medium size no/minimum-till seeders in Asia published in IJABE triggers a lot of scientific conversation on how to develop suitable no-till equipment among peer experts.This paper presents a collection of these post-publication peer review comments including commentary,questions,answers,suggestions,critical thinking,etc.The authors of the review article also provide response,summary of the review comments and their own standpoints.This open post-publication review and commentary may add value to the published review article and provide new ideas useful for future research and development of CA equipment.展开更多
基金financed by the National Natural Science Foundation of China (51175499)the Beijing Natural Science Foundation, China (6112015)the Australian Centre for International Agricultural Research (ACIAR)
文摘The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds (PRB) systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical (powered-chopper, powered-cutter and powered-disc) PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better (non-significant) than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.
文摘In Japan, common wheat is cultivated in upland fields converted from paddy fields, where poor drainage and high precipitation cause delay of sowing, lodging at the jointing stage, difficulty in topdressing at the ripening stage, and low yield. No-till cultivation has been promoted to overcome these problems but the yield is still low due to the lack of proper fertilizer application protocols. In this study, we determined whether an additional application of two kinds of Sigmoid coated urea as controlled availability fertilizers (CAFs) to the standard fertilization protocol for tillage cultivation can increase the yield and lodging resistance in no-till cultivated common wheat. Also, additional fertilization was applied to the seeding furrow simultaneously with seeding using a V-furrow no-till direct sowing (VFDS) machine. No-till cultivated plants had more tillers than tillage cultivated ones and consequently higher number of panicles and yield, caused by increased fertilizer application. The point-injected CAFs to the seeding furrow, which eluted at the jointing and ripening stages greatly increased the grain yield and protein content, respectively, compared to broadcast topdressing of ammonium sulfate at each stage. The simultaneous sowing and fertilization of additional CAFs using VFDS method in multi-year tests in farmers’ fields significantly increased the yield of no-till cultivated common wheat, and can be adopted by Japanese local farmers.
文摘The common practice of establishing rice in the rice-wheat system in India is manual transplanting of seedlings in the puddled soil. Besides being costly, cumbersome, and time consuming, puddling results in degradation of soil and the formation of a hard pan, which impedes root growth of subsequent upland crops. In addition, decreased availability and increasing cost of labor have increased the cost of rice cultivation through conventional methods. Because of these concerns, there is a need for mechanized transplanting of rice which is less labor-intensive and can ensure optimum plant population under nonpuddled and/or no-till conditions. A large number of on-farm trials were conducted at farmers’ fields in Haryana, India, from 2006 to 2010 to evaluate the performance of the mechanical transplanted rice (MTR) under nonpuddled and no-till situations as compared to conventional puddled transplant rice (CPTR). Compared with CPTR, nonpuddled MTR produced 3%-11% higher grain yield in different years. Rice cultivars, viz. HKR47, HKR127, PR113, PR114, PB1, PB1121, CSR30, and Arize6129, performed consistently better under nonpuddled MTR as compared to CPTR. Performance of different cultivars (PR113, PR114, HKR47, and Pusa 44) was also better under no-till MTR as compared to CPTR. The “basmati” cultivar CSR30 performed equally in no-till MTR and CPTR systems. The results of our study suggest that rice can be easily grown under nonpuddled and no-till conditions with yield advantages over the CPTR system. Even in the case of similar yield between CPTR and MTR systems, the MTR system will help in reducing labor requirement and ultimately, will increase overall profits to farmers.
基金Supported by the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province(LBH-Q14024)
文摘Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption,dust raising and interference from intertwined straw.In view of this,in this study,a driving roller dibbling-type no-till seeding and hole-forming(DGR-NT-SHF)system was designed to be capable of penetrating soil and creating holes without requiring any special preparation of the surface covering.The core mechanism of this system consisted of a land wheel-driven driving roller and a duckbill-type roller seeder,which were internally tangent to one another.The rotating roller rolled the straw into a thin layer,and the duckbills extended from the roller and penetrated this thin layer of straw and subsequently formed the holes and planted the seeds.Based on kinematic analysis,a mathematical model was established to depict the relations between the rear angle of the duckbill(α),the front angle of the duckbill(β),the angular velocity of the duckbill-type roller seeder(ω0),the angular velocity of the roller(ω1),and the aperture of the duckbill outlet on the roller(θ).In contrast to a driven roller-type no-till seeding and hole-forming DNR-NT-SHF system,several parameters of the DGR-NT-SHF system were established for planting seeds at a plant spacing that was an integral multiple of 100 mm:the radius of the duckbill-type roller seeder,200 mm;radius of the roller,400 mm;α,23°;andβ,5°.Based on the analysis of the models using the MATLAB Image Processing Module with a relation betweenω1 and the number of outlets on the roller as the constraint,the optimal number of outlets on the roller and theω1/ω0 ratio were determined to be 21 and 4/7,respectively.Kinematic simulation on a digital prototype was performed using computer aided three-dimensional interactive application(CATIA)to observe the motion of the DGR-NT-SHF system,when the duckbills on the duckbill-type roller seeder were open and to determine the locations of the duckbills relative to the outlets.To ensure the duckbills could be successfully opened,the chord length of the outlets was ultimately determined to be 71 mm.The prototype test results showed that the DGR-NT-SHF system met the design requirements and that the operation was straightforward and reliable.In addition,compared to the DNR-NT-SHF system,the DGR-NT-SHF system performed better in penetration and exerted no impact on the duckbills,thus providing an effective technical option for no-till seeding.
文摘Strawponic is an innovative and exotic system for growing potato on soil surface using crop straw as cover mulch. A field trial was carried out at the American University of Beirut in Lebanon to test the efficacy of this system for small potato producers. Barley (Hordeum vulgare) straw mulch at 25, 50 and 75 t/ha was used to cover potato tubers in no-till system. Potato plant number, height, number of shoots and leaves, root and shoot dry weight, and potato yield were collected. Results showed that all tested rates of straw significantly increased potato yield in comparison to the till system. Marketable yield was the highest with no-till potato at 50 and 75 t/ha compared to no-till potato at all tested surface straw rates. None of the treatments was harmful to potato plants compared to the till potato. This study could be a promising gate for production of potato for small-scale farmers.
文摘Global food demand requires that soils be used intensively for agriculture, but how these soils are managed greatly impacts soil fluxes of carbon dioxide (CO2). Soil management practices can cause carbon to be either sequestered or emitted, with corresponding uncertain influence on atmospheric CO2 concentrations. The situation is further complicated by the lack of CO2 flux measurements for African subsistence farms. For widespread application in remote areas, a simple experimental methodology is desired. As a first step, the present study investigated the use of Bowen Ratio Energy Balance (BREB) instrumentation to measure the energy balance and CO2 fluxes of two contrasting crop management systems, till and no-till, in the lowlands within the mountains of Lesotho. Two BREB micrometeorological systems were established on 100-m by 100-m sites, both planted with maize (Zea mays) but under either conventional (plow, disk-disk) or no-till soil mangement systems. The results demonstrate that with careful maintenance of the instruments by appropriately trained local personnel, the BREB approach offers substantial benefits in measuring real time changes in agroecosystem CO2 flux. The periods where the two treatments could be compared indicated greater CO2 sequestration over the no-till treatments during both the growing and non-growing seasons.
基金supported by the State’s Key Project of Research and Development Plan of China(Grant No.2021YFD2000401)the Heilongjiang Province Engineering Science and Technology Major Project of China(Grant No.2020ZX17B01)the National Modern Agricultural Industry Technology System Project(Grant No.GARS-04).
文摘To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was designed.Through simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was adopted.According to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and consistent.The standard error of the slope of the fitting equation of the downforce calculation model is 0.008.According to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,respectively.The coefficients of variation were 0.40,0.41,0.62,and 0.71,respectively.The results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting speed.Both the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.
基金National Natural Science Foundation of China(No.42207381)China Scholarship Council(No.201806350218).
文摘Whether biochar produced as a by-product of energy generation from the papermill industry,and often disposed in landfills,can be gainfully applied to commercial croplands has not been investigated.The objective of this study was to investigate the physical and hydraulic properties of soils in commercial cotton fields managed as no-till systems following repeated applications of biochar generated as a waste of a papermill plant.Undisturbed cores and disturbed soil samples were collected from 0-5 and 5-10 cm layers from five commercial no-till fields in Mississippi,USA that received 6.7 Mg ha^(−1) year^(−1) biochar for 0,2,3,5 or 10 years.A number of physical,hydraulic,and chemical properties of these samples were measured in the lab.The results showed that biochar reduced the degree of soil compactness and increased soil aggregation and structural stability index.The findings were particularly apparent for the 10 years of consecutive application,which increased soil aggregate stability by up to 67%,reduced bulk density from 1.40 to 1.26 g cm^(−3),and reduced degree of compactness from 73.2%to 62.8%.Biochar increased soil porosity but much of this increase(55%)occurred for small pores(<0.5μm)with little effect on storage pores(0.5-50μm)or transmission pores(>50μm).Consequently,biochar increased soil field capacity by up to 26%,but PAW increased by only 17%.Biochar significantly increased soil physical quality index score in the 0-5 cm layer from 0.16 to 0.26 and the increase was positively correlated with the number of years of application.The results suggest biochar generated as a byproduct of papermill could be land-applied in real-world crop production systems to improve soil health as an alternative to disposal in landfills.
基金This work was supported by the National Natural Science Foundation of China(Grant No.52175260)Gratitude should be expressed to all the members of the Conservation Tillage Research Centre.
文摘An adequate and uniform press wheel pressure is crucial for the homogeneous development of a crop,as it affects actual seeding depth and germination rate.The problems of uneven compaction of seed furrow and consistency of seeding depth can be caused by the pressure fluctuation of the coil-spring pressure control device(CPCD)when the no-till planter is working on the unplowed ground.In this study,a pneumatic pressure control device(PPCD)was designed for the no-till planter,the key structural parameters of air spring for press wheel pressure(PWP)stability were determined by theoretical analysis and parameter calculation.Using the gas-structure coupling finite element simulation method(FESM),the piston radius,piston angle,and cord angle of the air spring are selected as the test factors,and the vertical stiffness was used as the test index to carry out the quadratic rotation orthogonal combination test to establish the regression model of test index and factor.The bench test of the PPCD was carried out under the optimal parameter combination,piston radius of 27.2 mm,piston angle of 11.7°,and cord angle of 30.0°.The vertical stiffness verification test showed that the simulation test was consistent with the bench test result,the vertical stiffness simulation error was 7.1%,and the internal air pressure simulation error was 3.0%;The control response test showed that the average response time of the air spring inflating and deflating was 0.80 s,the maximum overshoot was 4.33%during inflation,and no pressure overshoot during deflation;Under the condition of-40-40 mm surface relief height,the PPCD could effectively reduce the pressure fluctuation compared with the CPCD,and the average reduction of the pressure fluctuation was about 25.1%.
基金supported by the Liaoning Revitalization Talents Program(Grant No.XLYC2007043)Scientific Research Fund Project of Liaoning Province(Grant No.LJKZZ20220087)from China Liaoning Province.
文摘Aiming at the problems of uneven plant spacing,row spacing and sowing depth due to the collision of seeds with the tube wall or bouncing on the floor of the seed guide tube with the increase of operation speed of the current corn no-till planter,in this study,the high-speed seed belt technology was combined with the finger clip seed discharge device,a kind of high-speed no-till planter monomer was designed and installed in high-speed seed tube.At the same time,simulation analysis was made on the movement law of seeds in the seed guide tube when they fell from the finger clip seeder and the main structural parameters and the range of key parameters of the high-speed seed tube were determined.Through the prototype,the single-factor and quadratic orthogonal rotational combination test method,and the machine operating speed,the height of the high-speed seed tube and the seed guide angle were selected as the test factors in the seeding performance test.After parameter optimization,the optimal working parameters were determined:the machine forward speed was 12.18 km/h,the height of the high-speed seed tube from the ground was 42.22 mm,and the seed guide angle of the high-speed seed tube was 8.82°.The field test verified that under this parameter combination,the qualified-seeding index was 94.95%,the multiple-seeding index was 2.37%,and the missing-seeding index was 2.48%,showing stable working performance and satisfied the sowing and agronomic requirements of the no-till seeding operation.
文摘The aim of this study was to evaluate the physiological quality and seed production of Fabaceae and corn in monoculture and intercropping in areas cropped under different management. The following treatments were evaluated: corn + NPK + weed control;corn + weed control;corn + NPK;corn + crotalaria;corn + jack bean. Intercropping raised the average number of corn ears of corn and the seed IVG Weed control positively influenced the final stand and average number of ears. NPK fertilization on corn sowing positively influenced the seed electrical conductivity. The yield of corn plants intercropped with crotalaria and jack bean was statistically similar. However, their absolute values should be considered for economic purposes. Corn seeds derived from intercropping with crotalaria were more effective compared with intercropping with jack bean. Crotalaria and jack bean seeds when intercropped with corn have high production, germination and vigor (IVG and emergence).
基金Project supported by the National Natural Science Foundation of China (No.40571151)the Beijing Key Lab of Resources Environment and GIS at Capital Normal Universitythe National High Technology Research and Development Program of China (863 Program) (Nos. 2002AA2Z4311 and 2002AA2Z4021).
文摘Although understood differently in different parts of the world, conservation tillage usually includes leaving crop residues on the soil surface to reduce tillage. Through a global review of long-term conservation tillage research, this paper discusses the long-term effect of conservation tillage on sustainable land use, nutrient availability and crop yield response. Research has shown several potential benefits associated with conservation tillage, such as potential carbon sequestration, nutrient availability, and yield response. This research would provide a better perspective of the role of soil conservation tillage and hold promise in promoting application of practical technologies for dryland farming systems in China.
文摘In 1999 no-tillage farming,synonymous of zero tillage farming or conservation agriculture,was adopted on about 45 million ha world wide,growing to 72 million ha in 2003 and to 111 million ha in 2009,corresponding to an growth rate of 6 million ha per annum.Fastest adoption rates have been experienced in South America where some countries are using no-tillage farming on about 70%of the total cultivated area.Opposite to countries like the USA where often fields under no-tillage farming are tilled every now and then,more than two thirds of the area under no-tillage systems in South America is permanently not tilled;in other words once adopted,the soil is never tilled again.The spread of no-tillage systems on more than 110 million ha world-wide shows the great adaptability of the systems to all kinds of climates,soils and cropping conditions.No-tillage is now being practiced from the artic circle over the tropics to about 50ºlatitude south,from sea level to 3,000 m altitude,from extremely rainy areas with 2,500 mm a year to extremely dry conditions with 250 mm a year.No-till farming offers a way of optimizing productivity and ecosystem services,offering a wide range of economic,environmental and social benefits to the producer and to the society.At the same time,no-till farming is enabling agriculture to respond to some of the global challenges associated with climate change,land and environmental degradation,and increasing cost of food,energy and production inputs.The wide recognition of no-till farming as a truly sustainable system should ensure the spread of the no-till technology and the associated practices of organic soil cover and crop rotation,as soon as the barriers to its adoption have been overcome,to areas where adoption is currently still low.The widespread adoption globally also shows that no-tillage farming cannot any more be considered a temporary fashion or a craze;instead largely through farmers’own effort,the system has established itself as a farming practice and a different way of thinking about sustainable agro-ecosystem management that can no longer be ignored by scientists,academics,extension workers,farmers at large as well as equipment and machine manufacturers and politicians.
基金supported by the National Natural Science Foundation of China (40771132)the Key Technologies R&D Program of China during the 11th Five-Year Plan period (2006BAD15B06)+3 种基金the Australian Center for International Agricultural Research (CIM-1999-094)the Education Department of Gansu Province, China (0802-07)the Research Fund for the Doctoral Program of Higher Education of China (20106202120004)the Gansu Provincial Key Laboratory of Aridland Crop Science
文摘Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture (CA) is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world's arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.
基金supported by the Program for Changjiang Scholars and Innovative Research Team in University of China(Grant No.IRT13039).
文摘The benefits of conservation agriculture(CA)have been widely recognized and CA has been widely adopted in many parts of the world.However,there are some factors that limit the widespread adoption of CA in Asia.The most prominent factor appears to be the lack of suitable CA seeders for small to medium sized land-holding(SLH)farmers.This paper summarizes the small to medium no-till and minimum-till seeders currently available in Asia,and classifies these seeders into four types:manually operated units,animal traction seeders,two-wheel tractor and four-wheel tractor driven seeders.Detailed characteristics have been provided for some typical CA seeders and comparisons were made as to their suitability under particular working conditions.Typically manual and animal traction seeders are confined to small farms and hilly areas,while the larger CA seeders suited to four-wheel tractors are used on larger acreages.To ensure seeding performance on most four-wheel tractor CA seeders,two types of anti-blocking mechanisms(passive and active anti-blocking)have been fitted.Finally,the paper proposes a future direction and development of CA seeders for small/medium size farms in Asia,and also suggests changes in policy support,improvement of anti-blocking mechanisms,suitability for various crops,geographical zones and the contribution of development by public private partnerships to advance the adoption of CA seeders.
基金This study was supported by the National Science and Technology Research Program(2013BAD08B01-3)the Soil-Machine-Plant Key Laboratory of Ministry of Agriculture of PR China.
文摘In the continuous annual wheat-corn cropping area of North China Plain,no-till planting that promotes soil conservation and crop yield while reducing operation cost has been gradually accepted by local farmers.However,previous wheat residue is the main limiting factor affecting the performance of existing planters in placing seeds at uniform spacing and optimum depth in residue covered fields.In order to solve this problem,a kind of ground-wheel-driven row cleaner was designed,developed and mounted on row units of a four-row pneumatic precision planter.The planter has two adjacent row units equipped with the newly designed row cleaners and the other two adjacent row units equipped with the commonly used inactive row cleaners.This was used for planting at three forward speeds(4 km/h,6 km/h and 8 km/h)into half residue(HR)and whole residue(WR)plots.The amount of residue removal,seeding depth,emergence rate and indices of uniformity in seed spacing(missing-seeding index,quality of feeding index and precision index)were measured.The newly designed row cleaner performed better with regard to residue removal,with the average percentage of residue cleared as 63.0%compared to 40.3%for the inactive row cleaner.For the HR and WR plots,percentage of residue cleared of the newly designed row cleaner reached 57.1%and 68.9%respectively,suggesting that the newly designed row cleaner can work more effectively at high residue level.By contrast,with the percentage of residue cleared of the inactive row cleaner as 43.1%and 37.5%in HR and WR plots,suggesting that the inactive row cleaner just can work effectively under low residue condition.Values of missing-seeding index,QFI,precision index,coefficient of variation of depth and percent emergence for the newly designed row cleaner under whole residue level are comparable to those for the inactive row cleaner under half residue level.The result indicates that the effect of using the newly designed row cleaner is equal to that of reducing surface residue,and can help to maintain the uniformity of seed spacing and seeding depth.The newly designed row cleaner generally performed better at forward speed of 6 km/h,based on the distribution of seeds along rows and seeding depth uniformity.
基金the supports of Special Fund for Agro-scientific Research in the Public Interest(201503117)National Industry System of Corn Technology(CARS-02)。
文摘No-till planters are very popular for maize seeding in fields covered with residue in annual wheat-maize double cropping system in North China Plain.However,there is no suitable depth control mechanism for existing no-till maize planters,and as a result,it is hard to obtain consistent planting depth,uniform emergence,and good passing ability at the same time.For the above reasons,a proper planting unit with a new type of depth-control mechanism was developed in this study.The mechanism consists of a single-side gauge wheel,a parallel four-bar linkage,a pair of double-disc opener,a V-shape press wheel and a depth regulator,which can adjust the planting depth from 30 mm to 90 mm to satisfy the agronomic requirement under different field conditions.Based on analysis and calculation,the width of gauge wheel was set to 50 mm while the length of parallel four-bar linkage was set to 350 mm.Field experiment was conducted and the results indicated that the newly designed planting unit with single-side gauge wheel performed well with regard to planting depth uniformity and anti-blocking ability.The planting depth uniformity and seed spacing quality were 95.45%and 91.90%,respectively,when the average height of stubble was 22.5 cm and residue amount was 0.64 kg/m^(2)in the field.It can satisfy the requirement of no-till maize planting on the cropland with residue and stubble in North China Plain.
文摘The U.S. Farm Bill includes conservation practices that benefit both the environment and the farmer. The USDA Conservation Effects Assessment Project (CEAP) is a multi-agency effort to assess the efficiency of conservation practices to minimize non-point source pollution. This is follow-up study of a 28-year experiment design to assess the influence of the conservation practices of no-till and crop rotation systems (corn [Zea mays]-soybean [Glycine max]), compared to chisel tillage and monocropping systems (continuous corn) on soil health and water quality. In this study, changes on soil C and N, soil water content, runoff, and losses of ammonium-N, nitrate-N, soluble reactive P (SRP), atrazine, metolachlor, and glyphosate were compared to determine the influence of no-till and corn-soybean rotation systems, relative to chisel tillage and continuous corn, on plots planted with corn using variable intensity rainfall simulations. The long-term no-till systems had a positive impact on soil C and N, soil water, runoff, and losses of ammonium-N and nitrate-N;however, no effect was observed on losses of SRP, atrazine, metolachlor, and glyphosate. The corn-soybean rotation negatively influenced, compared to the continuous corn, soil C and N, soil water content, and increased runoff and the losses of all nutrients and herbicides measured in this study. These results suggest that additional conservation practices, in conjunction with no-till and corn-soybean rotations are needed to reduce surface losses of nutrients and pesticides while improving soil health.
基金by the National Key R&D Plan Project(Grant No.2016YFD070030201)。
文摘Sowing depth has an important impact on the performance of no-tillage planters,it is one of the key factors to ensure rapid germination.However,the consistency of sowing depth is easily affected by the complex environment of no-tillage operation.In order to improve the performance of no-tillage planters and improve the control precision of sowing depth,an intelligent depth regulation system was designed.Three Flex sensors installed on the inner surface of the gauge wheel at 120°intervals were used to monitor the downward force exerted by the seeding row unit against ground.The peak value of the output voltage of the sensor increased linearly with the increase of the downward force.In addition,the pneumatic spring was used as a downforce generator,and its intelligent regulation model was established by the Mamdani fuzzy algorithm,which can realize the control of the downward force exerted by the seeding row unit against ground and ensure the proper seeding depth.The working process was simulated based on MATLAB-Simulink,and the results showed that the Mamdani fuzzy model performed well in changing the pressure against ground.Field results showed that when the operating speed was 6 km/h,8 km/h and 10 km/h,the error of the system’s control of sowing depth was±9 mm,±12 mm,and±22 mm,respectively,and its sowing performance was significantly higher than that of the unadjusted passive operation.
基金the financial support by the Program for Changjiang Scholars and Innovative Research Team in University of China(Grant No.IRT13039).
文摘Traditional agriculture bases most of its operations or practices on soil tillage,which causes likely occurrence of water and soil erosion and sediment runoff.In order to conserve soil,water and environment,Conservation agriculture(CA)is increasingly adopted to replace traditional tillage agriculture to achieve sustainable and profitable agriculture and subsequently improve the livelihoods of farmers.CA holds great potential for all sizes of farms and agro-ecological systems,but its adoption is most urgently required by smallholder farmers,especially those short of laborers.Small/medium size no-till machines and implements are the key to CA adoption.A review article on small/medium size no/minimum-till seeders in Asia published in IJABE triggers a lot of scientific conversation on how to develop suitable no-till equipment among peer experts.This paper presents a collection of these post-publication peer review comments including commentary,questions,answers,suggestions,critical thinking,etc.The authors of the review article also provide response,summary of the review comments and their own standpoints.This open post-publication review and commentary may add value to the published review article and provide new ideas useful for future research and development of CA equipment.