• Authors:
    • Nakayama, T.
  • Source: Agricultural and Forest Meteorology
  • Volume: 151
  • Issue: 3
  • Year: 2011
  • Summary: To account for complex and diverse water system involving river dry-up, groundwater degradation, agricultural/urban water use, and dam/canal effects in heavily irrigated Yellow River Basin, this study coupled NIES Integrated Catchment-based Eco-hydrology (NICE) model series with more complex sub-models involving various factors (NICE-DRY). The model reproduced reasonably evapotranspiration, irrigation water use, groundwater level, and river discharge during spring/winter wheat, summer maize, and summer rice cultivations. Scenario analysis predicted the impact of irrigation on both surface water and groundwater, which had previously been difficult to evaluate. The simulated discharge with irrigation was improved in terms of mean value, standard deviation, and coefficient of variation. Another scenario analysis of conversion from dryland to irrigated fields predicted that the effect of groundwater irrigation was predominant in the middle and downstream and the resultant groundwater degradation predominantly, where surface water was seriously limited. Simulated dry biomasses of wheat and maize were linearly related to Time-Integrated Normalized Difference Vegetation Index (TINDVI) estimated from satellite images. Temporal gradient of TINDVI during 1982-1999 showed spatially heterogeneous distribution and increasing trends in the wheat and maize fields, indicating that the production increases were related to irrigation water and the resultant hydrologic changes. This integrated approach could help to estimate a close relationship between crop production, hydrologic cycle, and water availability, and predict heterogeneous vulnerability of water resources. Because this region experienced substantial river dry-up and groundwater degradation at the end of the 20th century, this approach would help to overcome substantial pressures of increasing food demand and declining water availability, and to decide on appropriate measures for whole water resources management to achieve sustainable development under sound socio-economic conditions.
  • Authors:
    • Zhang, W.
    • Zheng, J.
    • Deng, A.
    • Chen, J.
    • Tian, Y.
  • Source: Acta Agronomica Sinica
  • Volume: 37
  • Issue: 2
  • Year: 2011
  • Summary: Climate warming presents significantly asymmetric trends with greatly seasonal and diurnal differences, greater temperature elevations existing in the winter-spring season than in the summer-autumn season and at the nighttime than at the daytime. To date, this is till lack of evidence about the effects of asymmetric warming on the quality of winter-wheat grain based on field experiments. Here, we performed field warming experiment under free air temperature increased (FATI) facility to investigate the impacts of asymmetric warming on the contents and components of starch and protein in winter-wheat grain during 2007-2009 in Nanjing, Jiangsu province, China. The results showed that the all-day warming (AW), daytime warming (DW), and nighttime warming (NW) treatments significantly advanced the grain-filling stage and changed the appearance time and days of high temperature above 32degreesC in grain-filling stage, consequently resulting in obvious changes of starch component, protein content and protein components. Treatments AW, DW, and NW had no significant impact on the starch content of winter-wheat grain but tended to increase the ratio of amylose content to amylopectin content. The highest values of the ratio of amylose content to amylopectin content existed in the DW plots which were 6.9% and 46.2% higher than those in the control plots in the two years, respectively. The content of grain protein was significantly decreased by warming with the content order of CK > DW > NW > AW. Warming decreased the grain protein contents by 9.1%, 5.4%, and 6.9%, respectively in the AW, DW, and NW treatments on average of the two years. The effects of warming on grain protein components were complicated. However, DW showed a regular impact on protein components. The two-year result showed that the lowest content of albumin and the greatest content of globulin occurred in the DW plot with the lowest ratio of glutelin content to gliadin content. All these results demonstrate that the effects of asymmetric climate warming on the quality of winter-wheat grain are complicated with significant differences among warming patterns and experimental years.
  • Authors:
    • Hoogmoed, W. B.
    • Cai, D.
    • Zhao, Q.
    • Wang, Y.
    • Zhang, X.
    • Zhang, D.
    • Dai, K.
    • Wang, X.
    • Oenema, O.
  • Source: Field Crops Research
  • Volume: 120
  • Issue: 1
  • Year: 2011
  • Summary: Rainfed crop production in northern China is constrained by low and variable rainfall. This study explored the effects of tillage/crop residue and nutrient management practices on maize ( Zea mays L.) yield, water use efficiency (WUE), and N agronomic use efficiency (NAE) at Shouyang Dryland Farming Experimental Station in northern China during 2003-2008. The experiment was set-up using a split-plot design with 3 tillage/crop residue methods as main treatments: conventional, reduced (till with crop residue incorporated in fall but no-till in spring), and no-till (with crop residue mulching in fall). Sub-treatments were 3 NP fertilizer rates: 105-46, 179-78 and 210-92 kg N and P ha -1. Maize grain yields were greatly influenced by the growing season rainfall and soil water contents at sowing. Mean grain yields over the 6-year period in response to tillage/crop residue treatments were 5604, 5347 and 5185 kg ha -1, under reduced, no-till and conventional tillage, respectively. Grain yields under no-till, were generally higher (+19%) in dry years but lower (-7%) in wet years. Mean WUE was 13.7, 13.6 and 12.6 kg ha -1 mm -1 under reduced, no-till, and conventional tillage, respectively. The no-till treatment had 8-12% more water in the soil profiles than the conventional and reduced tillage treatments at sowing and harvest time. Grain yields, WUE and NAE were highest with the lowest NP fertilizer application rates (at 105 kg N and 46 kg P ha -1) under reduced tillage, while yields and WUE tended to be higher with additional NP fertilizer rates under conventional tillage, however, there was no significant yield increase above the optimum fertilizer rate. In conclusion, maize grain yields, WUE and NAE were highest under reduced tillage at modest NP fertilizer application rates of 105 kg N and 46 kg P ha -1. No-till increased soil water storage by 8-12% and improved WUE compared to conventional tillage, thus showing potentials for drought mitigation and economic use of fertilizers in drought-prone rainfed conditions in northern China.
  • Authors:
    • Cai, D.
    • Deng, X.
    • Zhao, Q.
    • Wu, X.
    • Wang, X.
  • Source: Scientia Agricultura Sinica
  • Volume: 44
  • Issue: 11
  • Year: 2011
  • Summary: Changes in land use, especially in cropland-use management, induced by human activities is one of the most important factors influencing climate change. In China, facing the huge pressure of dealing with climate change, the research on the relations between cropland-use management and soil carbon (C) sink, and the effects of cropland-use management on soil C sequestration and C emission mitigation is important, aiming at providing a decision-making basis for improvement of soil C sequestration and C emission mitigation in China. Through the literature reviews, this paper analyzes the impact of cropland-use management on soil C sequestration and C emission mitigation in China. As literature reviewed, agriculture is not only a main source of C emission, but also a sink of C sequestration. Through improvement of cropland-use management (such as increasing straw return into the soil, organic fertilizer application, and no-till/reduced tillage practices, etc.), there has shown an increasing trend in soil C sink in cropland since the last 20 years. Based on the estimation of soil C sequestration in cropland in China, especially with the recommended management practices, especially in the future 50 years, the potential for soil C sequestration in cropland of China is estimated about 87-393 TgC.a -1, thus offsetting about 11%-52% of the total industry C emissions, in which improved cropland-use management (including straw return, organic fertilizer application, and no-till/reduced tillage) could share about 30%-36% of C sequestration. This shows that cropland-use management in China could play an important role in soil C sequestration and C emission mitigation.
  • Authors:
    • Wu, Z. J.
    • Zhu, A. N.
    • Chen, L. J.
    • Chen, Z. H.
    • Wang, J. B.
  • Source: Plant, Soil and Environment
  • Volume: 57
  • Issue: 6
  • Year: 2011
  • Summary: The effects of tillage and residue input amounts on soil phosphatase (alkaline phosphomonoesterase ALP, acid phosphomonoesterase ACP, phosphodiesterase PD, and inorganic pyrophosphatase IPP) activities and soil phosphorus (P) forms (total P, organic P, and available P) were evaluated using soils collected from a three-year experiment. The results showed that no-till increased soil total and organic P, but not available P as compared to conventional tillage treatments. Total P was increased as inputs of crop residue increased for no-till treatment. There were higher ALP and IPP activities in no-till treatments, while higher PD activity was found in tillage treatments and tillage had no significant effect on ACP activity. Overall phosphatase activities increased with an increase of crop residue amounts. Soil total P was correlated negatively with PD activity and positively with other phosphatase activities. Organic P had a positive correlation with ACP activity, but a negative correlation with PD activity. Available P had no significant correlation with phosphatase activities. Our data suggests that no-till and residue input could increase soil P contents and enhance the activities of phosphatase.
  • Authors:
    • Li, H.
    • Cheng, J.
    • Zhang, J.
    • Yue, T.
    • Xi, Z.
  • Source: Scientia Agricultura Sinica
  • Volume: 44
  • Issue: 11
  • Year: 2011
  • Summary: Objective: In this paper, the relationship between soil quality and soil biological characteristics such as soil microorganism quantity and soil enzymatic activity was studied in the intercropping system of vineyard, in order to illustrate the function of soil biological characteristics as bio-indicators of soil fertility. Method: Three such cover crops, two perennial legumes (white clover and alfalfa) and a perennial gramineous grass (tall fescue) were sown in vineyard. Soil microorganism quantity, soil enzymatic activities and soil nutrient content were analyzed and compared with that in soil cultivation. [Result] Most detected soil microorganism quantity and soil enzymatic activity, soil organic matter were increased under cover crop treatments, compared to clean tillage, tall fescue treatment decreased urease and sucrase activity. White clover and alfalfa treatments significantly increased the contents of hydrolyzable N, total N and available K, and tall fescue decreased them, while the activated organic P in tall fescue treatment was more effectively than that in white clover and alfalfa treatments. Correlation analysis indicated that soil organic matter, total N, hydrolyzable N, total P, available K showed significant or very significant positive correlation with 10 soil biological characteristic factors such as bacteria, fungi, actinomyces, azotobacter, cellulose-decomposing bacteria, urease, phosphatase, amylase, sucrase, and cellulose. The catalase activity was no significant correlation with all the soil nutrient contents, and the total K content was no significant correlations with all the soil biological characteristic factors. The soil pH in this experiment was negatively correlated with soil biological properties. Conclusion: Cover crops in the inter-rows of vineyard increased soil microorganism quantity, soil enzymatic activity and soil nutrient content, white clover and alfalfa treatments were better than tall fescue. There are significant correlations between soil biological characteristics and nutrients, and soil biological indexes could reflect the changes of soil quality.
  • Authors:
    • Yang, Z.
    • Guan, C.
    • Zhou, H.
    • Fan, G.
    • Xie, W.
  • Source: Nongye Jixie Xuebao = Transactions of the Chinese Society for Agricultural Machinery
  • Volume: 42
  • Issue: 11
  • Year: 2011
  • Summary: Based on the results from 18-year long-term location experiment in dryland experimental area of northern China, the effects of various kinds of straw return to field such as no straw returning (CK), straw mulching (SM), straw crushing (SC), cattle manure (CM) and different fertilization time i. e. spring and autumn on corn yield and water use efficiency were studied. The results showed that the experiment of combining autumn fertilizing with returning stalks to field could increase the yield and water use efficiency of spring maize significantly compared to the spring fertilizing, meanwhile, it decreased the accumulated water consumption and increased the soil water storage amount. The results showed that autumn fertilizing increased 9.71-15.58 t/hm 2 in yield, compared with spring fertilizing. The range of increased in yield was 8.33%-16.19%. The total corn yield and water use efficiency in the past 18-year decreased in the following order: CM > SM > SC > CK. In different rainfall years, the corn yield and water use efficiency were very different. In normal years, the corn yield was highest. In dry years, the water use efficiency of spring maize was highest and yield increasing effect from straw mulching combining with autumn fertilizing was striking.
  • Authors:
    • Du, R.
    • Cai, S.
    • Geng, D.
    • Song, J.
    • Yang, Z.
  • Source: International Agricultural Engineering Journal
  • Volume: 20
  • Issue: 2
  • Year: 2011
  • Summary: Based on the agronomic characteristics of yearly maize-wheat rotation in Huanghuaihai Plain, a new-concept no-till planter, named 2BMDF-8 no-till wheat-maize planter, has been developed by Shandong University of Technology to solve an extremely important problem, such as standing maize stubble in one pass in two-crop rotation areas of Shandong Province in China. The combine anti-blocking device that is composed of power chopping axle and the planting unit of double-disc opener was designed. The test results of field performance showed that the machine could accomplish many working procedures, such as stubble chopping, furrow opening, seeds and fertilizer placement etc, in one pass, so the operation cost could be decreased by about 30%. The machine worked well for planting wheat into fields with standing maize stubble and maize stubble shattered. The powered chopping axle resolved the anti-blockage problem that ahead of shank the double-disc opener unit reduced the blockage between planting units. Meanwhile the variations in seed depth reduced to 18.8% and 19.3% respectively. Therefore, this machine will be a good solution to no-till wheat-maize planting in two crop rotation areas.
  • Authors:
    • Xie, J.
    • Li, L.
    • Huang, G.
    • Cai, L.
    • Luo, Z.
    • Zhang, R.
  • Source: Acta Prataculturae Sinica
  • Volume: 20
  • Issue: 4
  • Year: 2011
  • Summary: Long-term field experiments on soil physical quality in rainfed farming systems were conducted in Dingxi on the western Loess Plateau. The effects of conventional tillage and five conservation agriculture patterns [conventional tillage (T), conventional tillage with stubble incorporation (TS), no till with no stubble (NT), no till with stubble retention (NTS), conventional tillage with plastic mulching (TP) and no till with plastic mulching (NTP)] were studied. The experiment was fully-phased with two rotation sequences. Phase 1 started with field pea ( Pisum sativum) followed by spring wheat ( Triticum aestivum) (P->W) whereas phase 2 started with spring wheat followed by field pea (W->P). There were highly significant differences between the six tillage measures in soil properties including soil aggregates, available water content, water use efficiency and saturation conductivity. There were also significant differences in some soil properties including soil bulk density, total porosity, capillary porosity, non-capillary porosity, soil strength and saturation capacity. There were no significant differences in soil properties such as soil temperature and field capacity. Using the addition and multiplication method, and weighted integrated method, quantitative assessments of soil physical quality in different tillage systems were carried out. The order of soil physical quality index from high to low was NTS, NTP, NT, TS, T(TP) and TP(T) in P->W rotation, and NTS, NTP, TS, NT, TP and T in W->P rotation. The various tillage measures resulted in very different soil physical quality levels. Improved soil structure arose from tillage reduction or residue retention which improved soil structure, enhanced water infiltration, reduced soil and water loss, and hence improved soil physical quality.
  • Authors:
    • Rasaily, R. G.
    • He, J.
    • Li, H.
    • Zhang, X.
  • Source: International Agricultural Engineering Journal
  • Volume: 20
  • Issue: 2
  • Year: 2011
  • Summary: Due to the problem of residues blocking and seriously damaged bed shape during the planting of wheat in maize stubble coverage fields under the condition of permanent raised beds in irrigated agricultural region of Northwest China, the throwing stubble and renovating the bed type no-till planter for wheat was designed. This paper mainly analyzed the reshaping plough, moving cutter and throwing stubble device. Furthermore, the key parameters were analyzed and determined. The field experiment showed that through adopting the anti-blocking principle that combined moving cutter and throwing stubble device and residue-cutting by knife type opener, the machine could solve the residue and weed blocking problem effectively. It also has a good performance of passing and cutting stubble, and renovating the beds. The seeding and fertilizing depths acquired by the planter were 47.2 mm and 85.6 mm, respectively, which indicates the planter could meet the requirements of wheat no-tillage planting in permanent raised beds farming system in agricultural region of Northwest China.