• Authors:
    • Chenglin, M.
    • Chunsheng, L.
    • Honglei, J.
    • Lichun, W.
    • Hongjie, T.
  • Source: Soil & Tillage Research
  • Volume: 107
  • Issue: 1
  • Year: 2010
  • Summary: The stalk-stubble breaking and mulching process is a core technique for some conservation tillage system. Over the past 10 years, this technique has been widely adopted in the dry farming area of northern China. On the basis of analyzing the existing problems in stalk-breaking and stubble-breaking machines, we have developed a combined stalk-stubble breaking and mulching machine with two frames fixed together, the stalk and stubble-breaking blade rotors were mounted respectively on the frames. The machine can be used to break the maize ( Zea mays L.) stalk and stubble and bury about one-third of the broken stalk and stubble in the soil, preventing them being blown away by wind. This paper describes the structural features of the machine, the design of main working parts, determination of the parameters of the central position of the two blade rotors, and presents the performance test results. The tests showed that the machine had a stalk-breaking rate of 89% and the vegetation coverage rate reached 67.9%, which meets the agro-technical requirements in the dry farming area of northern China.
  • Authors:
    • Wang, L.
    • van Ranst, E.
    • Li, C.
    • Tang, H.
    • Li, H.
    • Qiu, J.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 135
  • Issue: 1-2
  • Year: 2010
  • Summary: Agricultural production plays an important role in affecting atmospheric greenhouse gas concentrations. Field measurements were conducted in Quzhou County, Hebei Province in the North China Plains to quantify carbon dioxide (CO 2) and nitrous oxide (N 2O) emissions from a winter wheat-maize rotation field, a common cropping system across the Chinese agricultural regions. The observed flux data in conjunction with the local climate, soil and management information were utilized to test a process-based model, Denitrification-Decomposition or DNDC, for its applicability for the cropping system. The validated DNDC was then used for predicting impacts of three management alternatives (i.e., no-till, increased crop residue incorporation and reduced fertilizer application rate) on CO 2 and N 2O emissions from the target field. Results from the simulations indicated that (1) CO 2 emissions were significantly affected by temperature, initial SOC, tillage method, and quantity and quality of the organic matter added in the soils; (2) increases in temperature, initial SOC, total fertilizer N input, and manure amendment substantially increased N 2O emissions; and (3) temperature, initial SOC, tillage, and quantity and quality of the organic matter added in the soil all had significant effects on global warming. Finally, five 50-year scenarios were simulated with DNDC to predict their long-term impacts on crop yield, soil C dynamics, nitrate leaching losses, and N 2O emissions. The modelled results suggested that implementation of manure amendment or crop residue incorporation instead of increased fertilizer application rates would more efficiently mitigate GHG emissions from the tested agro-ecosystem. The multi-impacts provided a sound basis for comprehensive assessments on the management alternatives.
  • Authors:
    • Qin, L.
    • Shuang, L.
    • Wenquing, H.
    • Xurong, M.
    • Hoogenboom, G.
    • Changrong, Y.
    • Jiantao, D.
    • Ahmad, M.
    • Nangia, V.
  • Source: International Journal of Agricultural and Biological Engineering
  • Volume: 3
  • Issue: 2
  • Year: 2010
  • Summary: In the dryland regions of North China, water is the limiting factor for rainfed crop production. Conservation agriculture (featuring reduced or zero tillage, mulching, crop rotations and cover crops) has been proposed to improve soil and water conservation and enhance yields in these areas. Conservation agriculture systems typically result in increased crop water availability and agro-ecosystem productivity, and reduced soil erosion. To evaluate the potential of conservation agriculture to improve soil water balance and agricultural productivity, the DSSAT crop model was calibrated using the data of a field experiment in Shouyang County in the semi-arid northeastern part of the Yellow River Basin. The average annual precipitation at the site is 472 mm, 75% of which falls during the growing season. The site had a maize-fallow-maize rotation, data from two crop seasons (2005 and 2006) and four treatments for calibration and analysis were used. The treatments were: conventional tillage (CT), no-till with straw mulching (NTSM), all-straw incorporated (ASRT) and one-third residue left on the surface with no-till (RRT). The calibration results gave satisfactory agreement between field observed and model predicted values for crop yield for all treatments except RRT treatment, and for soil water content of different layers in the 150 cm soil profile for all treatments. The difference between observed and predicted values was in the range of 3%-25% for maize yield and RMSE was in the range of 0.03-0.06 cm 3/cm 3 for soil water content measured periodically each cropping season. While these results are encouraging, more rigorous calibration and independent model evaluation are warranted prior to making recommendations based on model simulations. Medium-term simulations (1995-2004) were conducted for three of the treatments using the calibrated model. The NTSM and ASRT treatments had similar or higher yields (by up to 36%), higher crop water productivity by up to 28% and reduced runoff of up to 93% or 43 mm compared to CT treatment.
  • Authors:
    • He, X.
    • Qin, S.
    • Hu, C.
    • Zhang, Y.
    • Dong, W.
  • Source: European Journal of Soil Biology
  • Volume: 46
  • Issue: 3-4
  • Year: 2010
  • Summary: This study compared the responses of soil chemical and microbial indicators to the conservational tillage (CT) versus traditional tillage (TT) in a Haplic Cambisol in the North China Plain (NCP). These indicators included soil organic C (SOC), soil total N (STN), soil available P (SAP), cation exchange capacity (CEC), exchangeable Ca 2+ and Mg 2+, microbial biomass C (MBC), microbial biomass N (MBN), alkaline phosphomonoesterase (AP), beta-glucosidase, N-acetyl-beta-glucosaminidase (NAG), nitrate reductase (NR), protease, urease and the geometric mean of the assayed enzymes (GMea). Our results showed that almost all investigated parameters, except the contents of CEC, Ca 2+, Mg 2+ and the ratios of GMea/MBN and C/N, were significantly higher under the CT (no-till, NT and reduced-till, RT) than those under the TT, whilst the crop yield was not significantly affected by tillage treatments. Principle component analysis (PCA) showed that the first and second component explained 67.2% and 16.6% of the total variation, respectively. The first component was significantly correlated with GMea, MBC, MBN and beta-glucosidase, and effectively discriminated soils under the NT or RT from those under the TT. Our results indicated that the 6-year CT improved the quality of the Haplic Cambisol by enhancing its chemical and microbial properties, whilst GMea, MBC, MBN and beta-glucosidase were among the most effective indicators for monitoring these improvements.
  • Authors:
    • Qin, S.
    • Hu, C.
    • He, X. H.
    • Dong, W.
    • Cui, J.
    • Wang, Y.
  • Source: Applied Soil Ecology
  • Volume: 45
  • Issue: 3
  • Year: 2010
  • Summary: Micro-scale investigation is helpful for better understanding of the relationships between organic matter, microorganisms and nutrients in soil, and for better interpretation of modifications induced by soil management. The soil particle-size fractions (2000-200, 200-63, 63-2, and 2-0.1 m), contents of soil organic carbon (SOC), total N (STN), available P (SAP), dissolved organic C (DOC), light fraction organic C (LOC), microbial biomass N (MBN), basal respiration (SBR), and relevant enzyme activities of C, N and P transformations, such as beta-glucosidase (beta-G), N-acetyl-beta-glucosaminidase (N-G), protease, urease and alkaline phosphomonoesterase (APH) were analyzed to study the effects of 8-year-period conservational (no-till with residue retention) (CAM) versus traditional agricultural management (moldboard plowing without residue retention) (TAM) to a Haplic Cambisol soil in the North China Plain (NCP). Our results showed that CAM significantly enlarged the stocks of SOC, DOC, LOC, STN and SAP in the 0-10 cm layer, increased the contents of SOC, STN and SAP in the sand fractions, and promoted all of the enzyme activities in the bulk soil and all of the four particle-size fractions. Our results suggested that CAM increased the nutrient contents in the sand fractions by both enlarging the content of particulate organic matter and enhancing the activities of enzymes involved in nutrient cycling in these fractions. On the contrary, the contents of SOC and nutrients in the silt and clay fractions were relatively resistant to the conversion from CAM to TAM, indicating the limitation of CAM for stable SOC sequestration.
  • Authors:
    • Hoogmoed, W. B.
    • Cai, D.
    • Wu, X.
    • Zhao, Q.
    • Zhang, X.
    • Wang, Y.
    • Dai, K.
    • Wang, X.
    • Oenema, O.
  • Source: Agricultural Water Management
  • Volume: 97
  • Issue: 9
  • Year: 2010
  • Summary: Rainfed crop production in northern China is constrained by low and variable rainfall, and by improper management practices. This study explored both the impact of long-term rainfall variability and the long-term effects of various combinations of maize stover, cattle manure and mineral fertiliser (NP) applications on maize ( Zea mays L.) yields and water use efficiency (WUE) under reduced tillage practices, at Shouyang Dryland Farming Experimental Station in northern China from 1993 onwards. The experiment was set up according to an incomplete, optimal design, with 3 factors at five levels and 12 treatments including a control with two replications. Grain yields were greatly influenced by the amount of rain during the growing season, and by soil water at sowing. Annual mean grain yields ranged from 3 to 10 t ha -1 and treatment mean yields from 4.2 to 7.2 t ha -1. The WUE ranged from 40 in treatments with balanced nutrient inputs in dry (weather/or soil) years to 6.5 kg ha -1 mm -1 for the control treatments in wet years. The WUE averaged over the 15-year period ranged from 11 to 19 kg ha -1 mm -1. Balanced combination of stover (3000-6000 kg), manure (1500-6000 kg) and N fertiliser (105 kg) gave the highest yield and hence WUE. It is suggested that 100 kg N per ha should be a best choice, to be adapted according to availability of stover and manure. Possible management options under variable rainfall conditions to alleviate occurring moisture stress for crops must be tailored to the rainfall pattern. The potentials of split applications, targeted to the need of the growing crop (response nutrient management), should be explored to further improve grain yield and WUE.
  • Authors:
    • Willett, I.
    • Hu, K.
    • White, R.
    • Wei, Y.
  • Source: Ecological Economics
  • Volume: 69
  • Issue: 11
  • Year: 2010
  • Summary: Agriculture's environmental footprint is expanding and one of its most critical impacts in China is the over-exploitation of surface water and groundwater from aquifers. This study investigated an approach for estimating the physical dimensions of the environmental externalities from a maize cropping system in oasis farming of the arid north-west of China, and the monetary valuation of these environmental externalities based on integrated process-based biophysical and economic models. The simulation results show that current farming practices cause 7854 Yuan/ha of groundwater recharge cost, 7696 Yuan/ha of water treatment cost, and 91 Yuan/ha of N 2O mitigation cost. These costs lead to a social benefit-cost ratio of only 0.55, although the farmers' benefit-cost ratio was 1.85. A combination of adoption of recommended best management practices by farmers, and an increase in the water price to 1.1 Yuan/m 3 could maintain both the social and farmers' benefit-cost ratios above 1, but the costs of recharging groundwater were large in all cases.
  • Authors:
    • Li, S.
    • Chen, X.
    • Liu, Y.
    • Zhu, L.
    • Xu, H.
  • Source: Scientia Agricultura Sinica
  • Volume: 43
  • Issue: 14
  • Year: 2010
  • Summary: Objective: A field experiment was carried out on typical Hap-Ustic Isohumisol soil on dry highland of loess plateau to study the absorption and translocation of nitrogen in different farmland water management patterns under the same N fertilizer rate, therefore, the result would have good application values in guiding high yield cultivation of maize. Method: Four field water management practices, including supplementary irrigation, rain-fed, corn straw mulching and plastic film mulching, were adopted in spring maize Xianyu 335. The amount and proportion of N from different management practices at 6 growing stages (seedling, jointing, tasseling, blister, dough and maturity) were measured. Result: The experimental results showed that with the growing stage increasing, N absorption increased. After tasseling stage, with the center of growth changing the absorption quantity of organs absorbing N was changed. In every growing stage the N amount in supplementary irrigation treatment was higher than other three treatments, followed by plastic film mulching treatment, rain-fed treatment and corn straw mulching treatment. In supplementary irrigation treatment, the amount of organs N translocation was 235.5 kg.hm -2, higher than other three treatments, followed by 225.3 kg.hm -2 in plastic film mulching treatment; straw mulching treatment was higher than rain-fed treatment, but the difference was not significant. Supplementary irrigation treatment and plastic film mulching treatment were significantly higher than other two treatments. Conclusion: Under the conditions of this experiment, in dry highland of loess plateau area, different farmland water management patterns had significantly effects on spring maize nitrogen absorption, distribution and translocation. The management patterns which can increase the yield, the water utilization efficiency and the nitrogen utilization efficiency can also increase the N absorption and the grain N content. Supplementary irrigation treatment and plastic film mulching treatment were better treatments in this experiment. As for the comprehensive water saving and rainfall use efficiency, the recommended management practice should be the plastic film mulching treatment based on the results of this experiment.
  • Authors:
    • Li, G.
    • Luo, C.
    • Wang, X.
    • Niu, Y.
    • Gao, C.
    • Nan, Z.
    • Shen, Y.
    • Yang, J.
  • Source: Acta Prataculturae Sinica
  • Volume: 19
  • Issue: 1
  • Year: 2010
  • Summary: The effects of conventional tillage (t), conventional tillage with stubble retention (ts), no-tillage (nt), and no-tillage with stubble retention (nts) treatment on crop yield, soil total nitrogen and carbon, total organic carbon, oxidizible organic carbon, and carbon pool management index (CPMI) were investigated within a maize-wheat-soy rotation system in the western Loess Plateau. Total crop yield for ten harvests during the years 2001 to 2007 under ts and nts treatments increased by 3.63 and 1.62 g/kg compared with conventional tillage, but decreased by 2.48 g/kg on the nt treatment. Total nitrogen contents under nts treatment were 15.4%, 30.2% and 16.2% higher than t, ts and nt treatments. Total carbon under nts treatment was significantly increased by 2.04 g/kg and total organic carbon were 2.50, 1.56 and 1.70 g/kg higher than under t, ts and nt treatment, respectively. Easily oxidized organic carbon under nts was 2.13 g/kg higher than under t treatment. TN/TC decreased by 12.75%, 15.97%, 6.87% and 24.16% under t, ts, nt and nts treatments. The CPMI under ts, nt and nts were 12.6%, 20.1% and 46.6% higher than under t, both stubble retention and no-till were beneficial to increasing the soil organic carbon content and improving the quality of the carbon pool.
  • Authors:
    • Zhang, X.
    • Shi, F.
    • Li, B.
    • Xue, Y.
    • Yang, Z.
  • Source: Journal of Henan Agricultural Sciences
  • Issue: 10
  • Year: 2010
  • Summary: By using field monitoring methods, the village, the water consumption of winter wheat grown Zhangcun town of Huixian county, Henan province were determined. Water consumption can reach 216.3-345.2 mm at the yield level of 4 500-6 000 kg/ha. The water consumption percentage constitution of different growing period was 25.9%-36.9% between seeding and reviving stages, 22.0%-31.1% between reviving and heading stages, and 31.9%-52.2% between heading and maturation. The variation was great among different years. When the yield level of corn was 6 750-7 500 kg/ha, water consumption 299.6-462 mm which account for 81.3%-97.4% of precipitation during the period of the year. The water consumption percentage constitution of different growing period was 17.1%-17.3% between seeding and jointing stages, 34.5%-39.1% between jointing and trumpet stages, and 43.6%-48.4% between trumpet and maturation stages. For both wheat and corn, the water consumption density increased dramatically after jointing stage. The jointing and seed filling stages were two important periods for wheat water consumption. The trumpet stage was important for corn. In the dry-land hilly areas of middle and north Henan province at the current situation, natural precipitation can generally meet the water demand of autumn grain crops, while for summer grain crops, it is inadequate. So the emphases of water-saving irrigation should be on the summer grain crops.