• Authors:
    • Li, R.
    • Wang, M.
    • Jia, Z.
    • Hou, X.
    • Yang, B.
    • Han, W.
    • Nie, J.
    • Zhang, R.
  • Source: Transactions of the Chinese Society of Agricultural Engineering
  • Volume: 28
  • Issue: 2
  • Year: 2012
  • Summary: In order to improve rainfall utilization efficiency and increase water availability for crops in dry farming area, a field experiment was conducted in 2007-2010 at Heyang Dryland Farming Experimental Station in Shaanxi province of China to determine the effect of different ridge and furrow with mulching cultivation patterns on soil water, soil temperature, yield of spring maize, and economic returns. The ridges were covered with common plastic film in all treatments, while different furrows were mulched with common plastic film, biodegradable film, corn straw, liquid film and uncovering, respectively. The flat plot without mulch was used as the control. The results obtained in a four-year experiment showed that, at the seedling stage of maize, the average temperature in 5-25 cm soil layer under common plastic film and biodegradable film were 2.4degreesC and 2.1degreesC higher than that of the control respectively. In contrast, the temperature under corn straw covering was 1.7degreesC lower than that of the control. Besides, the different rainwater harvesting treatments could improve soil moisture in the early growth of maize. There was no difference in the soil moisture level between corn straw, liquid film, uncovering and the control during the middle and late growth of maize. However, the soil moisture of common plastic film and biodegradable film in deep soil layer were lower than that of the control. Compared with the control, the 4-year average maize yield with biodegradable film, common plastic film, and corn straw mulching significantly increased by 35.2%, 34.7% and 33.6%, and the average water use efficiency increased by 30.6%, 30.2% and 28.6%, respectively. The total net income with corn straw mulching was the highest, followed by biodegradable film mulching, and the total net income increased by 3 299 and 2 752 Yuan/hm 2 respectively, compared to the control. It was concluded that when the ridges were covered with common plastic film, the furrows was mulched with biodegradable film or straw, not only the soil water and temperature conditions were improved, but also the maize yield and net income were increased. Therefore, these two treatments are considered as efficient for maize production in Weibei Highland area.
  • Authors:
    • Martins, M. dos R.
    • Angers, D. A.
    • Cora, J. E.
  • Source: Soil Science Society of America Journal
  • Volume: 76
  • Issue: 2
  • Year: 2012
  • Summary: In no-till systems, plants play a substantial role in soil physical conditioning because physical management is otherwise confined to sowing operations. We performed a study to determine the effect of 28 different crop sequences on soil water-stable aggregation, soil organic C (SOC), and the neutral carbohydrate composition of the surface layer (0-5-cm depth) of an Oxisol under no-till. Summer crop sequences with corn ( Zea mays L.) on a continuous basis or in rotation with soybean [ Glycine max (L.) Merr.] showed a higher mean weight diameter (MWD) of water-stable aggregates than those with a rice ( Oryza sativa L.)-bean ( Phaseolus vulgaris L.)-cotton ( Gossypium hirsutum L.) rotation. Among winter crops, pearl millet [ Pennisetum americanum (L.) Leeke] or grain sorghum [ Sorghum bicolor (L.) Moench] were associated with a higher MWD than oilseed radish ( Raphanus sativus L. var. oleiformis Pers.). Plant tissues of Poaceae species (corn, pearl millet, and sorghum) were enriched in pentoses relative to other plant species. A principal component analysis showed a close positive relationship of the soil aggregate MWD with the soil xylose content, but not with other soil monosaccharide and SOC contents, and a positive relationship with the amount of pentose input to the soil, notably from aboveground plant materials. A possible explanation is that pentosans are used as an energy source by filamentous microorganisms, which play a well-known role in stabilizing soil aggregates. Our results suggest that plant-derived carbohydrates mediate crop species effects on soil structure under no-till conditions, and this effect appears to be independent of changes in total SOC.
  • Authors:
    • Mehta, V. M.
    • Rosenberg, N. J.
    • Mendoza, K.
  • Source: Agricultural and Forest Meteorology
  • Volume: 152
  • Issue: 1
  • Year: 2012
  • Summary: The Missouri River Basin (MRB) is the largest river basin in the U.S. and is one of the most important crop and livestock-producing regions in the world. In a previous study of associations between decadal climate variability (DCV) phenomena and hydro-meteorological (HM) variability in the MRB for the March-August period, and their impacts on stream flow in the MRB, it was found that positive and negative phases of the Pacific Decadal Oscillation (PDO), the tropical Atlantic sea-surface temperature gradient variability (TAG), and the west Pacific Warm Pool (WPWP) temperature variability were significantly associated with decadal variability in precipitation and surface air temperature in the MRB, with combinations of various phases of these DCV phenomena associated with dry, wet, or neutral HM conditions. It was also found that these DCV phenomena impact stream flow in the MRB substantially via their association with MRB hydro-meteorology. In the present study, the Erosion Productivity Impact Calculator model, also known as the Environmental Policy Integrated Climate (EPIC) model, calibrated and validated for the MRB, was used to simulate yields of dryland corn ( Zea mays L.) and spring and winter wheat ( Triticum aestivum L.), in response to HM anomalies associated with the three DCV phenomena. Realistic values of indices of the three DCV phenomena have major impacts on crop yields, as much as 40-50% of average yield in some locations in the MRB and also evident in MRB-aggregated crop yields; however, our results show that the impacts can be location-specific. Since each of the three DCV phenomena can persist in one phase or another for several years to a decade or longer, and since the simultaneous correlation among these phenomena is negligibly small, their combined and cumulative positive/negative effects on the MRB HM and agricultural production can be dramatic in this major American and global "bread basket". In addition, EPIC's success in simulating long-term crop yields in the MRB, taking technology trends into account, suggests that, if the evolution of major DCV phenomena can be forecast, it may be possible to forecast, as well, some multiyear to decadal measure of crop yields in the MRB with some skill.
  • Authors:
    • Anderson, R. L.
    • Liebig, M. A.
    • Krupinsky, J. M.
    • Hanson, J. D.
    • Tanaka, D. L.
    • Merrill, S. D.
  • Source: Agricultural Systems
  • Volume: 107
  • Year: 2012
  • Summary: The dynamic cropping systems concept proposes a long-term strategy of crop sequencing to achieve production, economic and soil care goals through sound ecological management. This requires that agriculturalists have comprehensive information about how crop species affect following years' crops. Little research exists about how differences in soil type and properties change crop sequence effects. Sandy loam, alluvial-derived soil in south central North Dakota, USA (400 mm/yr precipitation) was the site of a crop sequence experiment in which four species - maize ( Zea mays L.), dry pea ( Pisum sativum L.), spring wheat ( Triticum aestivum L.), and soybean ( Glycine max (L.) Merr.) - were grown in strips one year and in perpendicular strips the following, with spring wheat planted a third year. No-till management was used with three replications in land and two in time. Results were compared with those from two 10*10 sequence experiments on silt loam, glacial till-derived soil. Soil water depletion (SWD) and root growth were deeper in sandy loam soil than in silt loam. During a year of above average precipitation, prior year soybean enhanced spring wheat yield on sandy loam soil by 14% above average, but prior year spring wheat reduced it by 14%. During a year of deficient precipitation, prior crop effects on spring wheat yield ranked in order of expected springtime soil water storage: dry pea, 11%; spring wheat, 4%; soybean, -5%; maize, -10%. Prior crops' SWD largely determined spring soil water, with maize having greatest depletion. Excluding results from a year of low precipitation, prior crops' effects on spring wheat yield on sandy loam soil were similar to results found at two sequence experiments on silt loam soil: dry pea - generally positive effect (N-production, water conservation); spring wheat - negative (disease); soybean - positive (N-production); maize - generally negative (heavier water use). Same year comparison of three crops (nine sequences) on sandy loam soil vs. silt loam showed average dry pea and spring wheat yields being equivalent ( P<0.10). However, average maize yield was 37% lower on silt loam, with maize-after-maize yielding 54% less. The site with sandy loam land had topsoil with lower soil quality indicators (organic C, water holding capacity) than silt loam. However, no-till management and previous grass rendered productivity of the soils equivalent, and superior capacity of the sandy loam site subsoil to conduct water and be conducive to root growth lessened negative, water-generated crop sequence effects.
  • Authors:
    • Stewart,B. A.
    • Blaser,B. C.
    • Mohammed,S.
  • Source: Journal of Crop Improvement
  • Volume: 26
  • Issue: 1
  • Year: 2012
  • Summary: Water for dryland grain production in the Texas panhandle is limited. Agronomic practices such as reduction in plant population or change in sowing time may help increase maize ( Zea mays L.) yield potential. Tiller formation under dryland conditions leads to more vegetative growth and reduced yield. We hypothesized that clump planting dryland maize would reduce environmental stress, tillering, and vegetative growth, and increase harvest index by having more soil water available during grain filling. Clump planting was studied during 2008 at Bushland, Texas. Two plant populations - 30,000 and 40,000 plants ha -1 - and three plant geometries - clumps of three or four plants (3 PPC or 4 PPC) and equally spaced single plants (ESP) - were grown in 75 cm rows. Growing season precipitation was 209 mm. Harvest index (HI) 200-seed mass and harvested ears were higher in 3 PPC and 4 PPC compared with ESP. Three PPC planted at 40,000 plants ha -1 had the highest harvest index of 0.46. The ESP produced 27% more unproductive ears compared with 3 PPC and 4 PPC. Leaf area index (LAI) was 14% more in ESP than in 4 PPC. The lower population produced higher HI and seed mass than the higher population, regardless of geometry. Grain yields were not significantly higher for clumps, yet increased number of productive ears, seed mass, and HI values, suggesting clump geometry may be a good strategy for dryland maize production.
  • Authors:
    • He, J.
    • Wang, Q.
    • Rasaily, R. G.
    • Li, H.
    • Lu, C.
  • Source: African Journal of Biotechnology
  • Volume: 11
  • Issue: 4
  • Year: 2012
  • Summary: An experiment was conducted to determine the effects of tillage on soil properties in the field of maize ( Zea mays L.) and winter wheat ( Triticum aestivum L.) annual double cropping region in North China Plain. Measurements were made following six years (2005 to 2010) of three tillage treatments; no till with controlled traffic (NTCT), no till random trafficking (NTRT) and conventional tillage (CT) on a silt loam according to the USDA texture classification system soil in Daxing district, which lies in the suburb of Beijing. Long term no till with controlled traffic significantly (P<0.05) increased macro-aggregates, infiltration rate, soil moisture, together with reductions in soil bulk density, soil compaction in different layers compared with the no till random traffic and traditional mould board tillage treatment currently used in this region. Consequently, mean winter wheat and summer maize yields for the NTCT treatment were improved by 2.8 and 7.1% when compared with the soils under no till random traffic, while huge improvement was found when it was compared with conventional ploughing management (4.2 and 12.08% for wheat and maize, respectively). The long-term experiment demonstrated that no-tillage controlled traffic with residues retained, offers a potentially significant improvement over the current farming systems in annual double cropping areas of North China Plain.
  • Authors:
    • Sampathkumar, T.
    • Pandian, B. J.
    • Mahimairaja, S.
  • Source: Agricultural Water Management
  • Volume: 103
  • Year: 2012
  • Summary: Field experiments were conducted during 2007-2009 to study the effect of deficit irrigation practices through drip irrigation system on soil moisture distribution and root growth in cotton-maize cropping sequence. Creation of soil moisture gradient is indispensable to explore the beneficial effects of partial root zone drying (PRD) irrigation and it could be possible only through ADI practice in paired row system of drip layout, that is commonly practiced in India. In the present study, PRD and deficit irrigation (DI) concepts (creation of soil moisture gradient) were implemented through alternate deficit irrigation (ADI) at two levels of irrigation using drip system. Experimental treatments comprised of six irrigation levels (full and deficit) through drip system with surface irrigation for comparison. Maize was sown after cotton under no till condition without disturbing the raised bed and drip layout. Roots confined to the shallow depth and recorded the lowest values for both the crops under conventional drip irrigation at 100% ETc. Among the deficit irrigation treatments, mild deficit irrigation produced longer lateral roots from both the sides of the plant. Contrary to rooting depth, severe water stress affected the lateral root spread and recorded lower values than other drip irrigation treatments. Soil moisture content (SMC) was low nearer to the plant (at 30 cm across the lateral) and far away (at 30 cm along the lateral) from the plant, irrespective of treatments. The reduction in SMC was increased at all locations as applied water level decreased. It is concluded that alternate watering imposed through ADI at 100% ETc produced longer lateral roots with higher values for root dry mass Alternate deficit irrigation (ADI) resulted uneven distribution of soil moisture content. Among the ADI treatments, ADI at 100% had less uneven distribution than ADI at 80% ETc.
  • Authors:
    • Seufert, V.
    • Ramankutty, N.
    • Foley, J. A.
  • Source: Nature
  • Volume: 485
  • Issue: 7397
  • Year: 2012
  • Summary: Numerous reports have emphasized the need for major changes in the global food system: agriculture must meet the twin challenge of feeding a growing population, with rising demand for meat and high-calorie diets, while simultaneously minimizing its global environmental impacts. Organic farming - a system aimed at producing food with minimal harm to ecosystems, animals or humans - is often proposed as a solution. However, critics argue that organic agriculture may have lower yields and would therefore need more land to produce the same amount of food as conventional farms, resulting in more widespread deforestation and biodiversity loss, and thus undermining the environmental benefits of organic practices. Here we use a comprehensive meta-analysis to examine the relative yield performance of organic and conventional farming systems globally. Our analysis of available data shows that, overall, organic yields are typically lower than conventional yields. But these yield differences are highly contextual, depending on system and site characteristics, and range from 5% lower organic yields (rain-fed legumes and perennials on weak-acidic to weak-alkaline soils), 13% lower yields (when best organic practices are used), to 34% lower yields (when the conventional and organic systems are most comparable). Under certain conditions - that is, with good management practices, particular crop types and growing conditions - organic systems can thus nearly match conventional yields, whereas under others it at present cannot. To establish organic agriculture as an important tool in sustainable food production, the factors limiting organic yields need to be more fully understood, alongside assessments of the many social, environmental and economic benefits of organic farming systems.
  • Authors:
    • Bortoluzzi, T.
    • Silva, C. A. T. da
    • Arieira, C. R. D.
    • Silva, T. R. B. da
  • Source: African Journal of Agricultural Research
  • Volume: 7
  • Issue: 2
  • Year: 2012
  • Summary: Poultry manure, applied like organic fertilizer on corn, has not been studied extensively; so, no one knows its effect on the genealogy of the soil. However, organic fertilizer does not cost much, it is easy to buy and it has less degree of environmental degradation as compared to chemical fertilizers. This study was conducted in the commercial fields of St. Helena/PR with corn, using the triple hybrid 2B688, established in 2008 with no-till farming for seven years in order to evaluate the effect of poultry manure on corn yield. The treatment used was chemical fertilizer having nitrogen in the formulation NPK with an addition of three doses of poultry manure (0, 3.5 and 7 t ha -1) and a witness; whereas the experimental design was randomized blocks with split plots and five replications. It was observed that the results were not significant for the number of rows per ear and grains per spike. Nevertheless, increased yield in corn was observed with 100% of poultry manure.
  • Authors:
    • Robertson, G.
    • Tausig, J.
    • Hamilton, S.
    • Basso, B.
    • Syswerda, S.
  • Source: Agricultural Ecosystems and Environment
  • Volume: 149
  • Year: 2012
  • Summary: Nitrate (NO 3-) loss from intensively farmed cropland is a long-standing, recalcitrant environmental problem that contributes to surface and groundwater pollution and coastal zone hypoxia. Here nitrate leaching losses are reported from nine replicated cropped and unmanaged ecosystems in southwest Michigan, USA. Ecosystems include four annual corn-soybean-winter wheat rotations under conventional, no-till, reduced-input, and organic/biologically-based management, two perennial cropping systems that include alfalfa and hybrid poplar trees, and three unmanaged successional communities including an early successional community analogous to a cellulosic biofuel system as well as a mature deciduous forest. The organic, alfalfa, and unmanaged systems received no synthetic, manure, or compost nitrogen. Measured nitrate concentrations were combined with modeled soil water drainage to provide estimates of nitrate lost by leaching over 11 years. Among annual crops, average nitrate losses differed significantly ( pno-till (41.33.0)>reduced-input (24.30.7) > organic (19.00.8) management. Among perennial and unmanaged ecosystems, nitrate loss followed the pattern alfalfa (12.81.8 kg N ha -1 yr -1)=deciduous forest (11.04.2) >> early successional (1.10.4)=mid-successional (0.90.4) > poplar (<0.010.007 kg N ha -1 yr -1) systems. Findings suggest that nitrate loss in annual row crops could be significantly mitigated by the adoption of no-till, cover crops, and greater reliance on biologically based inputs, and in biofuel systems by the production of cellulosic rather than grain-based feedstocks.