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    Soil organic carbon changes due to nutrient management practices in dryland maize under reduced tillage in China.
    Wang, X.B. ; Cai, D.X. ; Hoogmoed, W.B. ; Perdok, U.D. ; Oenema, O. - \ 2007
    In: Simulation of Soil Organic Carbon Storage and Changes in Agricultural Cropland in China and its Impact on Food Security. - Beijing : China Meteorological Press - p. 146 - 159.
    Comparison of tillage systems for paddy rice in the Mekong Delta of Vietnam
    Nguyen, V.L. ; Hoogmoed, W.B. ; Perdok, U.D. - \ 2007
    In: Proceedings of the 16th International Soil Tilage Organization, ISTRO Conference, Brisbane Australia, 13 - 18 July, 2007. - Brisbane, Australia : International Soil Tillage Research Organization - p. 674 - 679.
    In the Mekong delta of Vietnam, wetland rice is the main crop. The traditional rice cropping system with one crop per year changed to a system with two or three crops per year, and mechanised tillage replaced traditional tillage by water buffaloes. Currently, three tillage systems can be distinguished: dry tillage (ploughing and/or rotovating of the unsaturated field), wet tillage (puddling) or a mix of the two systems. The heavy monsoon rainfall causes many problems and strongly reduces the trafficable and workable periods. Tillage requires a high energy input and time pressure is high due to the short periods between crops. Whenever possible, farmers prefer dry tillage in view of soil structural quality, resistance of the crop to lodging (anchoring) and the experience that the typical soil profile is kept in better condition, resulting in higher yields. Experiments were carried on typical heavy clay soils (near Cantho, Cantho province) comparing the three tillage systems in terms of: quality of the seedbed (aggregate size, smoothness), the structure of the arable layer, bearing capacity of the hardpan, and energy expenditure and timeliness of the tillage operations. It was found that (dry) ploughing with a disk plough had a low energy consumption (about 40% of that of the rotavator) but produced a very poor seedbed. Additional disk harrowing or rotary tillage was necessary. One pass with the rotary tiller produced a good seedbed. Where secondary tillage operations on dry soil are required, drying of the soil for at least 6 days is needed to achieve an acceptable quality of the seedbed. A good alternative for the assessment of the surface condition of a rice-seedbed is collecting and quantifying the amount or number of clods larger than 80 mm at the surface.
    Crop residue, manure and fertilizer in dryland maize under reduced tillage in northern China: I grain yields and nutrient use efficiencies
    Wang, X.B. ; Cai, D.X. ; Hoogmoed, W.B. ; Perdok, U.D. ; Oenema, O. - \ 2007
    Nutrient Cycling in Agroecosystems 79 (2007)1. - ISSN 1385-1314 - p. 1 - 16.
    nitrogen use efficiency - soil fertility - water-use - management - systems - rice - wheat - plain - budgets - losses
    The rapidly increasing population and associated quest for food and feed in China has led to increased soil cultivation and nitrogen (N) fertilizer use, and as a consequence to increased wind erosion and unbalanced crop nutrition. In the study presented here, we explored the long-term effects of various combinations of maize stover, cattle manure and nitrogen (N) and phosphorus (P) fertilizer applications on maize (Zea mays L.) yield and nutrient and water use efficiencies under reduced tillage practices. In a companion paper, we present the effects on nutrient balances and soil fertility characteristics. The ongoing factorial field trial was conducted at Shouyang Dryland Farming Experimental Station in northern China from 1993 onwards. The incomplete, determinant-optimal design comprised 12 treatments, including a control treatment, in duplicate. Grain yields and N, P, and potassium (K) uptakes and N, P and K use efficiencies were greatly influenced by the amount of rain during the growing season (GSR), and by soil water at sowing (SWS). There were highly significant interactions between GSR and added stover and manure, expressed in complex annual variations in grain yield and N, P and K use efficiencies. Annual mean grain yields ranged from 3,000 kg ha¿1 to 10,000 kg ha¿1 and treatment mean yields from 4,500 kg ha¿1 to 7,000 kg ha¿1. Balanced combination of stover (3,000¿6,000 kg), manure (1,500¿6,000 kg) and N fertilizer (105 kg) gave the highest yield. Stover and manure were important for supplying K, but the effects differed greatly between years. Overall mean N recovery efficiency (NRE) ranged from 28% to 54%, depending on N source. NRE in wet years ranged from 50% to 90%. In conclusion, balanced combinations of stover, manure and NP fertilizer gave the highest yield and NRE. Reduced tillage with adding stover and manure in autumn prior to ploughing is effective in minimizing labor requirement and wind erosion. The potentials of split applications of N fertilizer, targeted to the need of the growing crop (response farming), should be explored to further increase the N use efficiency.
    Crop residue, manure and fertilizer in dryland maize under reduced tillage in northern China: II nutrient balances and soil fertility.
    Wang, X.B. ; Hoogmoed, W.B. ; Cai, D.X. ; Perdok, U.D. ; Oenema, O. - \ 2007
    Nutrient Cycling in Agroecosystems 79 (2007)1. - ISSN 1385-1314 - p. 17 - 34.
    organic-matter - bench marks - management - phosphorus - nitrogen - rice - carbon - water - environment - potassium
    A long-term experiment was carried out in the dryland of northern China to assess the effects of applications of maize stover, cattle manure and NP (1:0.44) fertilizer on partial nitrogen (N), phosphorus (P) and potassium (K) balances, extractable soil N (SEN), P and K, and soil organic matter (SOM) in a spring maize cropping system, under reduced tillage conditions. The experiment was set-up according to an incomplete, optimal design, with three factors at five levels and 12 treatments, including a control with two replications. Statistical analyses using multiple regression models showed that the partial N, P and K balances were strongly influenced by annual variations in the amounts of soil water at seeding (SWS) and growing season rainfall (GSR). Most treatments had positive P but negative N and K balances. Cumulative P and K balances were reflected in extractable soil P (P-Olsen) and K (exchangeable K), but the weak relationships indicated that the sorption of P and buffering of K were strong. Cumulative balances of effective organic carbon (C) were weakly related to soil organic C (SOC) content after 12 years. Negative C balances were related to decreases in SOC, but positive C balances were not translated into increases in SOC. The analysis of nutrient balances and soil fertility indices revealed that nutrient inputs in most treatments were far from balanced. It is concluded that the concepts of `ideal soil fertility level¿ and `response nutrient management¿ provide practical guidelines for improving nutrient management under the variable rainfall conditions of dry land areas in northern China.
    Developments in conservation tillage in rainfed regions of North China
    Wang, X.B. ; Cai, D.X. ; Hoogmoed, W.B. ; Oenema, O. ; Perdok, U.D. - \ 2007
    Soil & Tillage Research 93 (2007)2. - ISSN 0167-1987 - p. 239 - 250.
    Dryland regions in northern China account for over 50% of the nation's total area, where farming development is constrained by adverse weather, topography and water resource conditions, low fertility soils, and poor soil management. Conservation tillage research and application in dryland regions of northern China has been developed since the 1970s. Demonstration and extension of conservation tillage practices is actively stimulated by the Chinese government since 2002, following the recognition of the increased rate of degradation of the environment due to erosion and water shortage in North China. This paper reviews the research conducted on conservation tillage in dryland regions of northern China, and discusses the problems faced with the introduction and application of conservation tillage practices. Most of the studies reported have shown positive results of soil and water conservation tillage practices. These practices generally involve a reduction in the number and intensity of operations compared to conventional tillage, with direct sowing or no-till as the strongest reduction. Crop yields and water use efficiency have increased (with up to 35%) following the implementation of reduced tillage practices. Under no-till, crop yields are equivalent to or higher than those from conventional tillage methods, especially in dry years. However, during wet years yields tend to be lower (10¿15%) with no-till. Other benefits are an increased fallow water storage and reductions in water losses by evaporation. In order to fully exploit the advantages of conservation tillage, systems have to be adapted to regional characteristics. Farmers¿ adoption of conservation tillage is still limited.
    Conservation tillage for dryland farming in China
    Cai, D.X. ; Ke, J. ; Wang, X.B. ; Hoogmoed, W.B. ; Oenema, O. ; Perdok, U.D. - \ 2006
    In: Proceedings of the 17th ISTRO conference, Kiel, Germany, August 28th - Sept. 3rd., 2006. - Kiel, Germany : International Soil Tillage Research Organization - p. 1627 - 1633.
    Dryland regions account for above 70% of total nation's farmland in China. These dryland are vital contributors to the total national production of grains, cash crops and animal products. However, the development of dryland farming is constrained by harsh climate, bad economic situation and poor knowledge on land management. Even though the conservation tillage research and application in dryland regions of China has been actively promoted since 1980s, the conventional tillage is still prevalent in these regions. The bottleneck for sustainable agriculture in China is still the lack of knowledge amongst both farmers and extension organizations about practices pertained to sustainable land management. In this paper, we analyzed the regional characteristics and regional adaptation of conservation tillage systems in China’s dryland regions; reviewed the research conducted on conservation tillage in China, and discussed the problems faced with the introduction and application of conservation tillage practices in order to gain a better perception of the role of soil conservation tillage and promote application of practical technologies for dryland farming systems in China. To ensure a wider adoption of conservation tillage, several actions should be strengthened. These include: 1) strengthen the on-the ground, pilot field activates and further intensify the demonstration 2) optimize information, instruction, support and guidance of the farmer 3) enact specific legislation for the development, adoption and implementation of conservation agriculture.
    Advances in soil dynamics
    Perdok, U.D. - \ 2006
    Journal of Terramechanics 43 (2006)2. - ISSN 0022-4898 - p. 259 - 262.
    Dust storm erosion and its impact on soil carbon and nitrogen losses in Northern China
    Wang Xiaobin, ; Oenema, O. ; Hoogmoed, W.B. ; Perdok, U.D. ; Cai, D. - \ 2006
    Catena 66 (2006)3. - ISSN 0341-8162 - p. 221 - 227.
    loess plateau - wind erosion - deposition - elements - land
    There is increased awareness of the environmental impacts of soil carbon (C) and nitrogen (N) losses through wind erosion, especially in areas heavily affected by dust storm erosion. This paper reviews the recent literature concerning dust storm-related soil erosion and its impact on soil C and N losses in northern China. The purpose of our study is to provide an overview of the area of erosion-affected soils and to estimate the magnitude of soil C and N losses from farmland affected by dust storm erosion. According to the second national soil erosion remote-sensing survey in 2000, the area affected by wind erosion was 1.91 million km2, accounting for 20% of the total land area in China. This area is expanding quickly as the incidence of heavy dust storms has greatly increased over the last five decades, mainly as a result of the intensification of soil cultivation. The economic and ecological damage caused by wind erosion is considerable. Heavily affected areas show a loss of nutrients and organic carbon in soils and the heavily degraded soils are much less productive. Compared with the non-degraded soil, the C and N contents in degraded soils have declined by 66% and 73%, respectively. The estimated annual losses per cm toplayer of soil C and N by dust storm erosion in northern China range from 53 to 1044 kg ha¿ 1 and 5 to 90 kg ha¿ 1, respectively. Field studies suggest that soil losses by wind erosion can be reduced by up to 79% when farmers shift from conventional soil tillage methods to no-till. Thus shifting to no-till or reduced tillage systems is an effective practice for protecting soil and soil nutrients. Our study indicates that soil conservation measures along with improved soil fertility management measures should be promoted in dry-land farming areas of northern China. As erosion is a major mechanism of nutrient withdrawal in these areas, we plead for the development of accurate methods for its assessment and for the incorporation of erosion, as a nutrient output term, in nutrient budget studies.
    Potential effect of conservation tillage on sustainable land use : a review of global long-term studies
    Wang Xiaobin, ; Cai, D. ; Hoogmoed, W.B. ; Oenema, O. ; Perdok, U.D. - \ 2006
    Pedosphere 16 (2006)5. - ISSN 1002-0160 - p. 587 - 595.
    soil organic-matter - no-till - conventional tillage - southern alberta - crop yield - seedling establishment - corn production - winter-wheat - grain-yield - clay soil
    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.
    Characterisation of soil profile roughness
    Zhixiong, L. ; Nan, C. ; Perdok, U.D. ; Hoogmoed, W.B. - \ 2005
    Biosystems Engineering 91 (2005)3. - ISSN 1537-5110 - p. 369 - 377.
    By using a laser profiler, the surface height variation trace of three types of tillage soil profiles, that is ploughed, harrowed and rolled surface, are obtained. In order to acquire the different direction profiles of every tillage type, the profiles at 0 (parallel), 45 and 90 (perpendicular) degrees with respect to the tillage direction are measured. Using this data the range of root mean square (rms) height and correlation values associated with each agricultural roughness state is estimated. The agricultural soil profile is simulated by using random fractal model. The results show that at spatial scales, agricultural surface roughness characterisation are well described by the superposition of a single-scale process related to the tillage state with a multi-scale random fractal process related to field topography
    Nutrient dynamics in a dryland corn cropping system in Northern China : Effects of crop residue, animal manure and NP fertilizer applications
    Wang Xiaobin, ; Oenema, O. ; Hoogmoed, W.B. ; Cai Diangxiong, ; Perdok, U.D. - \ 2005
    In: Plant Nutrition for Food Security, Human Health and Environmental Protection / Li, C.J., Zhang, F.S., Doberman, A., Hinsinger, P., Lambers, H., Li, X.L., Marschner, P., Maene, L., McGrath, S., Oenema, O., Peng, S.B., Rengel, Z., Shen, Q.R., Welch, R., Von Wirén, N., Yan, X.L., Zhu, Y.G., Beijing : - p. 1066 - 1067.
    Wind erosion and its impact on soil carbon and moisture scarcity
    Wang Xiaobin, ; Cai, D. ; Oenema, O. ; Perdok, U.D. ; Hoogmoed, W.B. - \ 2005
    This review discusses the duststorm-related soil erosion and its impact on soil carbon losses and moisture scarcity in northern China. Heavily affected areas show a loss of nutrients, organic carbon and field water capacity of soils. Compared with nondegraded soil, the carbon content in degraded soils has declined by 66 percent, and field water capacity by about 50 percent. Field studies suggest that soil losses by wind erosion can be reduced by up to 79 percent when farmers change from conventional tillage methods to no till. Thus, shifting to no-till or reduced-tillage systems is an effective practice for protecting soil and soil nutrients. Our study indicates that soil conservation measures along with improved soil fertility management measures should be promoted in dryland farming areas of northern China.
    Rainfall effects on rainfed crop yields and water use
    Wang Xiaobin, ; Cai, D. ; Perdok, U.D. ; Hoogmoed, W.B. ; Oenema, O. - \ 2005
    Scenario analysis of tillage, residue and fertilization management effects on soil organic carbon dynamics
    Wang Xiaobin, ; Cai Diangxiong, ; Hoogmoed, W.B. ; Oenema, O. ; Perdok, U.D. - \ 2005
    Pedosphere 15 (2005)4. - ISSN 1002-0160 - p. 473 - 483.
    long-term experiments - simulating trends - matter dynamics - no-tillage - model - sequestration - systems - agriculture - grassland - fallow
    Based on data from 10-year field experiments on residue/fertilizer management in the dryland farming region of northern China, Century model was used to simulate the site-specific ecosystem dynamics through adjustment of the model's parameters, and the applicability of the model to propose soil organic carbon (SOC) management temporally and spatially, in cases such as of tillage/residue/fertilization management options, was identified via scenario analysis.Results between simulations and actual measurements were in close agreement when appropriate applications of stover,manure and inorganic fertilizer were combined. Simulations of extreme C/N ratios with added organic materials tended to underestimate the measured effects. Scenarios of changed tillage methods, residue practices and fertilization options showed potential to maintain and enhance SOC in the long run, while increasing inorganic N slowed down the SOC turnover rate but did not create a net C sink without any organic C input. The Century model simulation showed a good relationship between annual C inputs to the soil and the rate of C sequestration in the top 20 cm layer and provided quantitative estimations of changes in parameters crucial for sustainable land use and management. Conservation tillage practices for sustainable land use should be integrated with residue management and appreciable organic and inorganic fertilizer application, adapted according to the local residue resource, soil fertility and production conditions. At least 50%residue return into the soil was needed annually for maintenance of SOC balance, and manure amendment was important for enhancement of SOC in small crop-livestock systems in which crop residue land application was limited
    Analysis of tillage soil surface roughness
    Lu, Z.X. ; Wu, X.P. ; Perdok, U.D. ; Hoogmoed, W.B. - \ 2004
    Transactions of the Chinese Society of Agricultural Machinery 35 (2004)1. - ISSN 1000-1298 - p. 112 - 116.
    A scenario analysis of conservation tillage effects on soil organic carbon dynamics for dryland farming systems of northern china
    Wang Xiaobin, ; Hoogmoed, W.B. ; Oenema, O. ; Perdok, U.D. - \ 2004
    In: Conservation tillage and sustainable farming, 2004 CIGR International Conference, Beijing, 11-14 October 2004. - Beijing : China Agricultural Science and Technology Press - p. 18 - 24.
    Method for predicting selective uprooting by mechanical weeders from plant anchorage forces
    Kurstjens, D.A.G. ; Kropff, M.J. ; Perdok, U.D. - \ 2004
    Weed Science 52 (2004)1. - ISSN 0043-1745 - p. 123 - 132.
    bean phaseolus-vulgaris - reduced herbicide use - tine implements - yield response - soil failure - spring wheat - sugar-beet - inter-row - seedlings - crops
    Reliable mechanical weed control requires knowledge of the achievable levels of weed control and crop damage when using certain implements in specific conditions. Quantitative methods that use weed, crop, soil, and cultivator characteristics to predict weed control and crop damage need to be developed. To that end, the relative susceptibility of weeds and crop plants to mechanical weeding and the selective ability of cultivators need to be quantified separately. The method presented in this study uses measured plant anchorage forces to quantify crop and weed sensitivity to being uprooted by a weed harrow and predicts the relationship between weed and crop uprooting by mechanical weeding. Uprooting and anchorage force of young perennial ryegrass and garden cress plants were measured in laboratory harrowing experiments on sandy soil. A nonlinear equation was introduced to describe the relationship between weed uprooting and crop uprooting. The parameters representing the selective potential of the actual crop-weed condition (K-pot) and the imlement selective ability (K-cult) did not depend on crop uprooting. The relationship between potential weed and crop uprooting that could theoretically be obtained by a perfectly selective implement (i.e., pulling each plant with equal force) was calculated from plant anchorage force distributions measured before harrowing. The observed uprooting percentages achieved by harrowing were lower than the potential uprooting percentages. With K-cult accounting for imperfect weeder selective ability, prediction accuracy was satisfactory. Field validation is required to confirm whether this method improves comparison and prediction of weeding performance of different weeding implements in different crop-weed situations.
    Soil ridge geometry for green control in French fry potato production on loamy clay soils in The Netherlands
    Kouwenhoven, D. ; Perdok, U.D. ; Jonkheer, E.C. ; Sikkema, P.K. ; Wieringa, A. - \ 2003
    Soil & Tillage Research 74 (2003)2. - ISSN 0167-1987 - p. 125 - 141.
    Green potato (Solanum tuberosum L.) tubers are rejected by the processing industry. Therefore their amount should be reduced to minimum. The objective of this study was to assess the reduction of greening of new French fry varieties in experiments conducted from 1998 to 2001 on ridge qualities like geometry and the compression and crumbling degree of the loose soil in the ridge. The experiments were mainly carried out on the experimental husbandry farm Westmaas on a Calcaric Fluvisol having a clay content of ca. 200 g kg¿1. French fry potato varieties used were Agria and Fambo, whereas Bintje was used as a reference. Row spacings were 0.75 m (30 in.) and 0.90 m (36 in.). Net ridge size was determined by the internal height (distance between the plate and the top of the ridge) and by the width of the top of the ridge combined with planting near the surface of the plate. For the traditional French fry variety Bintje a reduction in greening was achieved by ridges having a gross size of 0.06¿0.07 m2. New French fry potato varieties like Agria and Fambo, however, are characterized by higher yields, larger cluster widths and longer tubers than Bintje. These properties favor the greening of tubers and require adjustment of the ridge geometry. Increase of the internal height and of the top width were found to be crucial to reduce greening of tubers to minimum. An increase of the top width of standard 0.75 m ridges from 0.15¿0.18 to 0.25 m combined with an internal height of 0.18¿0.20 m was realized by the so-called plateau ridges. This ridge type required ca. 0.04 m deeper seedbed than the depth of the seedbed for standard 0.75 m ridges. Without deeper loosening of the seedbed such larger ridges could also be realized by an increase of row spacing to 0.90 m. Net yields of new French fry varieties of plateau and 0.90 m ridges were generally similar or higher than the yields of standard 0.75 m ridges with the same internal height. With 0.90 m ridges over-sizing occurred sometimes. Greening of new varieties of French fry potatoes was reduced to minimum by the new knowledge on ridge geometry: an increase of the internal ridge height to 0.18¿0.20 m, a top width to 0.25 m and reduction of cracking by relatively coarse, non-compressed ridges.
    Tillage and residue effects on rainfed wheat and corn production in the Semi-Arid Regions of Northern China
    Wang, X.B. ; Hoogmoed, W.B. ; Perdok, U.D. ; Cai, D.X. - \ 2003
    In: Proceedings of the 16th International ISTRO Conference, Brisbane, Australia, 13 - 18 July, 2003. - Brisbane, Australia : International Soil Tillage Research Organization - p. 1354 - 1359.
    Field studies on tillage and residue management for spring corn were conducted at two sites, in Tunliu (1987-1990), and Shouyang (1992-1995) counties of Shanxi province in the semihumid arid regions of northern China. This paper discusses the effects of different fall tillage (winter fallow tillage) and residue application methods on soil water profile with time and water use, as well as corn yields. Conservation tillage practices for corn in Shouyang resulted in significantly higher soil water contents, especially in the 0-100 cm profiles during April-July and September, than under conventional tillage, providing more available water for corn growth due to increased soil water storage during the rainy season. Conservation tillage with residue application practices generally led to yield advantages. Increases of 18-26% were found for reduced tillage with residue incorporation over the conventional systems. Yields under no-till were equivalent to those from conventional methods, especially in dry years. These results suggest that the following two alternatives -both reducing the number of secondary tillage passes after the main operation for spring corn production systems: - using deep ploughing with incorporated straw and fertilizers after harvest in fall, and no-till seeding practices - using subsoiling between rows or no-till with residue mulching after harvest in fall, and no-till seeding practices.
    Laboratory assessment of the workable range of soils in the tropical zone of Veracruz, Mexico
    Hoogmoed, W.B. ; Cadena Zapata, M. ; Perdok, U.D. - \ 2003
    Soil & Tillage Research 74 (2003)2. - ISSN 0167-1987 - p. 169 - 178.
    physical-properties - tillage - implements - models
    Information on workability limits is highly valuable at the farm level to help the farmer in deciding when and possibly how to carry out tillage. On higher levels (e.g. on regional scale) this knowledge will form a basis for obtaining guidelines with respect to required number of tractors, equipment etc. and so help in planning and policy making. Data of this kind are often lacking. The study reported here is the laboratory component of research carried out in the tropical area of Veracruz, Mexico. In this study, laboratory methods to determine workability limits were assessed for a typical clay and loam soil. For the dry workability limit (where energy for producing specifically sized aggregates is the decisive factor), the drop test was applied. Results in terms of soil moisture tension at the point of lowest energy expenditure were comparable with the field results. although energy levels were different. For the determination of the wet workability limit (WWL), an air permeability test and a compression test were used. Both tests yielded limits that were very close to the ones determined in the field. The compressibility test allows the assessment of other soil characteristics such as prediction of modification of pF curve and aeration properties under compressive forces. For field or farm scale, workability limits can be obtained from representative areas and then used in combination with water balance models to determine the number of workable days under a certain weather (rainfall) regime. The applicability on a regional scale is as yet more difficult, soil physical information from soil maps is usually not sufficient to allow reliable interpretations. The use of existing pedo-transfer functions to obtain input for models to predict workable days did not produce satisfactory results. (C) 2003 Elsevier B.V. All rights reserved.
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