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Applying a salinity response function and zoning saline land for three fi eld crops: a case study in the Hetao Irrigation District, Inner Mongolia, China

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Journal of Integrative Agriculture 2015年第1期14卷 178-189页

作者： TONG Wen-jie CHEN Xiao-li WEN Xin-ya CHEN Fu ZHANG Hai-lin CHU Qing-quan shadrack batsile dikgwatlhe College of Agriculture and Biotechnology China Agricultural University/Key Laboratory of Farming SystemMinistry of Agriculture Beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry Sciences

Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat （Triticum aestinum L.）, maize （Zea mays L.） and sunflower （Helianthus annuus L.）, growing in 76 farm fields are evaluated with modified discount function. Salinity ecological zones appropriate for these local crops are characterized and a case study is presented for crop salinity ecological zoning. The results show that the yield reductions of wheat, maize and sunflower when grown in saline soils are attributed primarily to a reduction in spikelet number, 1 000-grain weight and seed number per head, respectively. Sunflower is the most tolerant crop among the three which had a salinity tolerance index （ST-index） of 12.24, followed by spring maize and spring wheat with ST-Indices of 9.00 and 7.43, respectively. According to the crop salinity tolerance results, the arable land in the Heping Village of this district was subdivided into four salinity ecological zones： the most suitable, suitable, sub-suitable and unsuitable zones. The area proportion of the most suitable zone for wheat, maize and sunflower within the Heping Village was 27.5, 46.5 and 77.5%, respectively. Most of the most suitable zone occurred in the western part of the village. The results of this study provide the scientific basis for optimizing the local major crop distribution and improving cultural practices management in Hetao Irrigation District.

关键词： salinity tolerance modified discount function ecological zoning Hetao Irrigation District

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保护性耕作对农田碳、氮效应的影响研究进展

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生态学报 2013年第19期33卷 6006-6013页

作者：薛建福赵鑫 shadrack batsile dikgwatlhe 陈阜张海林中国农业大学农学与生物技术学院农业部农作制度重点开放实验室北京100193

作物产量的高低主要取决于土壤肥力,如何保持并提高土壤肥力是确保我国粮食安全和农业可持续发展的重要任务,也是众多学者关注的焦点。土壤有机碳和氮素是评价土壤质量的重要指标,其动态平衡直接影响土壤肥力和作物产量。随着全球气候... 详细信息

作物产量的高低主要取决于土壤肥力,如何保持并提高土壤肥力是确保我国粮食安全和农业可持续发展的重要任务,也是众多学者关注的焦点。土壤有机碳和氮素是评价土壤质量的重要指标,其动态平衡直接影响土壤肥力和作物产量。随着全球气候变化及环境污染问题的愈加突出,农田土壤固碳及提高氮效率成为各界科学家研究的热点。目前,保护性耕作已成为发展可持续农业的重要技术之一,对土壤固碳及氮素的利用具有很大的影响。深入了解保护性耕作对土壤有机碳固持与氮素利用效率提高的影响机制,对于正确评价土壤肥力有着重要意义。但由于气候、土壤及种植制度等条件不一致,关于保护性耕作对农田碳、氮效应结论不一。阐述了国际上保护性耕作对农田系统土壤有机碳含量变化及其分解排放(如CO2和CH4)、氮素变化及其矿化损失(如NH3挥发、N2O排放与氮淋失)和碳氮素相互关系(如C/N层化率)影响的研究进展,并分析了其影响因素和相关机理。尽管国内保护性耕作的研究已进行30多年,但在土壤有机碳与氮素方面与国外相比依然有较大的差距。保护性耕作对土壤固碳与氮素利用的影响机制,碳素和氮素在土壤-植株-大气系统中的转移变化,及结合农事管理等综合评价其生态效应的研究很少。在此基础上,提出未来我国保护性耕作在土壤有机碳固定和氮素利用方面的重点研究方向:(1)在定位试验基础上进一步探讨保护性耕作对土壤有机碳及氮素利用的影响机制;(2)深入研究土壤有机碳和氮素的相互关系及其对土壤肥力的影响;(3)结合环境保护与土壤可持续管理对保护性耕作农田土壤固碳及氮素高效利用的系统评价研究;(4)加强保护性耕作对农田碳、氮效应的宏观研究,合理评价保护性耕措施下对农田碳、氮综合效应。

关键词：保护性耕作土壤肥力土壤质量土壤有机碳氮利用

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Maize （Zea mays L.） Growth and Grain Yield under Conventional and Site-Specific Nitrogen Management in a Dryland Farming System

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Journal of Agricultural Science and Technology(B) 2014年第8期4卷 602-611页

作者： Suzan Mashego Brilliant Mareme Petja Matshwene Edwin Moshia shadrack batsile dikgwatlhe Limpopo Department of Agriculture Directorate of Research Services Polokwane 0700 South Africa Department of Plant Production Soil Science andAgricultural Engineering University ofLimpopo Sovenga 0727 South Africa Department of Crop Science Tshwane University of Technology Pretoria 0001 South Africa College of Agronomy and Biotechnology China Agricultural University Beij'ing 100094 China

Large amount of pre-plant nitrogen （N） fertilizer results in low N use efficiency due to poor synchrony between soil N supply and maize N demand, especially during N sensitive growth stages. The objectives of the study were to compare growth and yield of maize （Zea rnays L.） under conventional and site-specific N management in a dryland farming system. The study, which was designed as randomized complete block design was conducted over three site-years under continuous maize cropping system in the semi-arid regions of the Limpopo Province in South Africa. Treatments of the study consisted of three N management strategies on a maize field planted to drought resistant SNK 2147 hybrid maize cultivar. Treatments were：（i） no N application （NO）, （ii） site-specific N at variable rates ranging between 18 kg N/ha and 33 kg N/ha based on soil analysis results （N l） and （iii） conventional and uniform N application broadcasted during planting at 58 kg N/ha （N2）. Sufficiency index as indication of N deficiency was determined using CCM-200 on maize leaves based on leaf numbers during maize vegetative growth stages V6, V10 and Vl4, and thereafter N was applied only when needed. The highest maize grain yield of 5.2 Mg/ha for N 1 was significantly higher （P 〈 0.05） than 3.2 Mg/ha and 4.0 Mg/ha of N0 and N2 in site-year I, respectively. Maize grain yield of 2.2 Mg/ha （Nl） at site-year ll was significantly higher （P _〈 0.05） than 1.7 Mg/ha of the NO. The maize growth and yield under N2 and N1 was compared, N1 required between 43% and 69% lesser N fertilizer as compared to N2 over site-years, and resulted in higher maize height, number of leaves per plant, leaf length, and leaf area than that of conventional N management strategy. Therefore, site-specific N management strategy sustains and improves growth and yield of maize using minimal N fertilizer as compared to conventional approach in low fertility soils of semi-arid regions in dryland farming systems. In examining the results of

关键词： Africa maize grain yield nitrogen management precision agriculture

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