不同土壤肥力与施肥处理对黄瓜产量及经济效益的影响

通过田间试验,探讨了不同土壤肥力与施肥处理对黄瓜产量、效益的影响.结果表明：在不同土壤肥力条件下施用氮、磷、钾肥能最大限度提高黄瓜产量和纯收益;其中增产率和增收率最高的处理为中等肥力土壤条件下,施氮、磷、钾肥的处理,增产率达到73.75％,增收率达到65.65％.氮、磷、钾对黄瓜产量的影响程度为氮＞磷＞钾.因此,为提高黄瓜产量及效益必须高度重视科学施肥,改变农民重氮肥、轻磷、钾肥的施肥习惯,从而提高农民种植黄瓜的经济效益.     

从农民种植习惯谈种子营销

在农业生产中,各地种植作物的种类、品种及种植模式存在着明显的区域性,这种区域性的种植特点常被称为农民种植习惯。作为直接服务于农民的种子营销,与农民种植习惯有着相互的作用和影响。本文拟从分析他们之间的关系入手,探寻做好营销的有效途径。     

红壤旱地施用氮磷钾肥对不同作物后效的研究

通过氮磷钾不同配比施用对几种种植制度的作物产量、经济效益以及土壤肥力状况的比较，结果表明：几种耕作方式；春大豆－秋芝麻－油菜、春大豆－秋绿豆－油菜，甜瓜－秋大豆－油菜，比当地习惯种植春大豆／／红薯－油菜，分别增加纯收入89．9％，28．8％，12．7％，定位施用氮磷钾肥，5个处理对全年作物的产量效益变化是NPK＞NP＞P＞N＞ck，一年施用一季NPK肥，即每公顷N120：P60：K90就可以获得最佳的丰产效果，三季作物总产较不施肥增加22．5％－25．0％，且经济效益增加纯收入9349．5－10759元／hm^2；定位施用NPK肥，能提高土壤有机质含量1．9％－19．9％，同时能满足每季作物所需N的含量，不同施肥处理，其土壤有效养分变化各不相同。     

香榧林下复合种植模式对皖南山区土壤养分保持的影响

在山地进行种植作业通常要考虑防治土壤侵蚀，起到涵养水源，调节地表径流和减少养分流失的作用。本研究对安徽省黄山市休宁县鹤城乡境内香榧基地山场里4种复合种植与1种香榧单种模式进行探讨。通过比较土壤养分的总量和迁移状况分析复合种植模式对该类型山地土壤养分保持的影响。结果表明：（1）香榧—掌叶覆盆子复合种植(T1)对土壤总氮、总磷、总钾、速效钾和pH的影响显著，其含量分别比香榧单种(CK)提高了1.2倍、0.5倍、0.2倍、0.3倍和0.1倍；香榧—黄精复合种植(T2)对土壤总磷、有效磷、总钾、速效钾的影响更为明显，其含量分别比CK提高了0.4倍、2.3倍、0.2倍和0.3倍；香榧—前胡复合种植(T3)对土壤速效钾和pH的影响更为明显，分别比CK提高了0.5倍和0.1倍；香榧—艾蒿复合种植(T4)同样对土壤速效钾和pH的影响更为明显，分别比CK提高了0.2倍和0.1倍。（2）土壤养分在坡顶、坡腰和坡底处分布不均衡，其中香榧—黄精和香榧—艾蒿复合种植对有效磷的分布影响均较大。（3）复合种植后土壤pH和含水率均有一致性变化，相关性分析表明pH和含水率与土壤养分含量分别成显著正相关和显著负相关关系。...     

耗竭土壤钾素的固定及对棉花钾素营养的作用

用室内模拟和生物耗竭的方法研究了土壤中钾素的变化，试验结果表明，淹水可以减少土壤对外源钾素的固定，淹水比20％田间含水量钾素的固定减少2－29mg/kg。当土壤经过干湿以后，土壤会发生明显的固定钾作用，土壤含钾量越高，固定钾能力越强。棉花吸收的钾素中有80％来自于土壤非交换性钾，盆栽生物耗竭与连续种植10年棉花的田间土壤，具有相同的结果，土壤交换性钾在下降到一定程度后不再下降，而1mol/L HNO3不能提取的钾（层间钾）一直在下降。     

氮、磷、钾对设施蔬菜产量及养分循环的影响

为了增加农民收入,减少肥料浪费,研究氮、磷、钾肥施用对蔬菜产量的影响,以及氮、磷、钾肥在蔬菜、土壤中累积量。进行一个周年轮作设施番茄、菜花、芹菜田间施肥试验。当番茄、菜花、芹菜不施N、P、K肥时,减产6.0%~13.8%,年总收入分别减少39220元/hm2、36902元/hm2、22023元/hm2;氮、磷、钾素是蔬菜产量的限制因子。蔬菜中N吸收量：番茄和菜花＞芹菜,P吸收量：菜花＞番茄和芹菜,K吸收量：番茄＞芹菜＞菜花;番茄果实中氮吸收量低于菜花果实氮吸收量,植株氮吸收量也低于菜花植株。而果实中磷、钾的吸收量是高于植株,并且钾吸收量明显高于植株。氮、磷、钾吸收总量顺序为菜花＞番茄＞芹菜。番茄、菜花和芹菜收获后的土壤氮、磷、钾含量均高于种植前的土壤含量;受底施有机肥的影响,番茄土壤中残留氮含量、芹菜土壤残留磷含量都高于基础土壤含量2倍以上;菜花没施有机肥,土壤残留氮、钾含量低于番茄和芹菜。土壤残留磷含量比较高,造成资源浪费,也污染土壤环境。     

机插水稻适宜秧龄的研究进展

适宜秧龄及秧龄弹性是机械化插秧技术研究的核心。本文阐述了适宜秧龄对机插水稻的重要性,概述了国内外机插水稻适宜秧龄的研究进展,并从种植制度、种植品种、育秧方式、农民意愿以及农艺与农机发展等方面,提出了机插水稻适宜秧龄研究所存在的问题和展望。     

徐州市多元高效生态型种植制度的研究

徐州市在全面推进新一轮农业结构调整的实践中，以改革传统以粮为主的单元低效的种植制度为突破口,系统地进行了多元高效生态型种植制度及配套技术的研究，总结形式并建立了六大类型地区的多元高效生态型种植制度，即西部高沙土地区创汇特菜高效生态型种植模式、近城靠矿地区设施多元高效生态型种植模式、沿湖沿运低洼稻区渔／稻高效生态型种养模式、丘陵地区油果瓜菜多元高效生态型种植模式、平原地区菜菜稻多元高效生态型种植模式、故黄河沿岸林草牧高效生态型种养模式。     

硫酸钾对三类幼龄茶园土壤钾库及其平衡的影响

选取川、渝两地典型、具有代表性的砂岩黄壤、灰岩黄壤、酸性紫色土为供试土壤,进行了连续5年的试验.研究了钾肥(硫酸钾)对茶园土壤钾库及钾素平衡的影响,旨在为茶树合理施肥提供科学的依据.研究结果表明施用钾肥显著提高土壤钾库中的各类钾素,且土壤中各类钾素的变化因土壤类型而异,在3种土壤中,土壤钾库的增量均为灰岩黄壤＞砂岩黄壤＞酸性紫色土.在不施钾肥(CK)的情况下,茶树每年从土壤取走0.08g/kg土钾素,3种土壤的钾素流失量分别为0.18g/kg·土年(灰岩黄壤)、0.09 g/kg·土年(砂岩黄壤)、0.07 g/kg·土·年(酸性紫色土).推测幼龄茶园土壤的钾素流失量与之类似,施用K肥很有必要.     

不同耕种方式对水土流失及产量的影响

经3年不同耕种方式对水、土、养分及作物产量影响研究,结果表明,沿等高线种植比顺坡种植减少流失水量53.5％、土量85.7％、养分总量84.3％,产量提高17.6％间作比净作减少流失水量22.2％、土量56.4％、养分总量51.4％,产量提高23.0％。浅耕比翻耕减少流失水量10.4％、土量21.6％、养分15.7％,增加产量10.O％。在各处理组合中,沿等高线种植、间作、淡耕的流失量最小,顺坡种植、净作、翻耕的流失量最大。试验证明,通过采用合理的耕种方式能极显著地减少旱坡耕地的水、土、养分流失量和大幅度提高作物产量。     

蔬菜种植模式对涂地土壤性状及蔬菜连作障碍的影响

为探讨蔬菜种植模式和种植年限对蔬菜地土壤性状及蔬菜生长障碍发生的影响,在浙东滨海涂地区按蔬菜种植年限（5~10年和10~20年）和种植模式（水稻 蔬菜年内连作、露天蔬菜-水稻轮作、露天蔬菜、冬季大棚蔬菜 夏季露天蔬菜和常年大棚蔬菜）分组鉴定土壤质量与蔬菜地连作障碍,并与长期种植水稻等粮食作物的农田进行比较。结果表明：种植蔬菜后,土壤容重呈增加的趋势;与长期种植水稻的用地相比,露天蔬菜、露天蔬菜-水稻轮作和水稻 蔬菜年内连作有利于土壤结构的改善,但长期种植大棚蔬菜则可导致土壤结构的恶化。种植蔬菜后,土壤酸度增加,有机碳下降,磷素、氮素、有效钾和盐分明显增加,对大棚蔬菜地的影响比露天蔬菜地更为明显。土壤中磷素、氮素、有效钾的积累和土壤酸化随着蔬菜种植年限的增加而呈现增加的趋势;种植蔬菜也显著增加了土壤过氧化氢酶、磷酸酶、脲酶和脱氢酶活性。研究区内蔬菜地连作障碍类型主要有病害、地下虫害、土壤理化性质恶化和缺素等,其发生比例随蔬菜种植年限明显增加,由低至高依次为：水稻 蔬菜年内连作地<露天蔬菜-水稻轮作地<露天蔬菜地<冬季大棚蔬菜 夏季露天蔬菜地<常年大棚蔬菜地。研究认为,蔬菜与水稻轮作可减少蔬菜连作障碍的发生。     

湖北省不同油菜轮作模式下作物施肥现状调查

为湖北省油菜生产建立高效施肥技术体系,通过农户走访调查,研究湖北省五类油菜轮作模式下的农户肥料施用情况及存在的主要问题。结果表明,湖北省油菜施用有机肥和硼肥的农户比例分别占20.2%和69.4%;油菜氮(N)、磷(P2O5)、钾(K2O)肥用量平均分别为203.7、71.3、50.2 kg/hm2,施用比例平均为1:0.35:0.25;油菜当季氮(N)、磷(P2O5)、钾(K2O)肥用量平均占轮作周年总用量的49.3%、51.6%、50.8%。农户氮肥用量偏高、钾肥明显不足,养分施用不平衡;区域间和农户间施肥量差异大,过量与不足现象并存;不同轮作模式下肥料统筹不合理;有机肥料施用不足,硼肥有待普及。根据作物营养生理需求及轮作制度分类指导,树立可持续农业施肥新观念,实现养分资源效益最大化,促进油菜等种植业的发展。     

Yield and quality components of silage maize in killed and live cover crop sods

In sloping areas with high precipitation, planting maize into live winter cover crop sods may help to alleviate the environmental problems associated with clean-tillage production systems of maize. The present study evaluates the performance of silage maize (Zea mays L.) under several cultivation methods: CC (conventional cropping system, i.e., maize was sown into the bare, autumn-ploughed soil); LGS/CK (maize was planted into a living Italian ryegrass (Lolium multiflorum Lam.) sod which was subsequently herbicidally killed); and LGS/MR (similar to LGS/CK, but the ryegrass was mechanically regulated). The research was conducted in the midlands of Switzerland on a fertile sandy loam under humid conditions during three cropping seasons. With 110 kg N ha⁻¹ (fertilizer nitrogen plus mineral nitrogen of the soil at maize planting), the CC system was much more productive than were the LGS/CK and LGS/MR systems in terms of dry matter and nitrogen yields of maize. Increasing the nitrogen supply to 250 kg N ha⁻¹ considerably reduced the yield advantage of CC over the LGS/CK and LGS/MR systems, indicating that nitrogen was the most limiting factor for maize yield in the mulch seeding systems. With 250 kg N ha⁻¹, the LGS/CK and LGS/MR systems produced greater total yields of digestible organic matter (maize plus ryegrass) than did the CC system, whereas the total nitrogen yield was similar for all cropping systems. The whole-shoot concentrations of nitrogen were highest under CC, irrespective of the level of nitrogen supply. With 110 kg N ha⁻¹, concentrations of phosphorus and magnesium were clearly higher for the mulch seeding systems. There were only minor differences among the cropping methods in the concentrations of potassium and calcium in the whole shoot. When 250 kg N ha⁻¹ were applied, there were no significant variations among the cropping systems in the concentrations of minerals. Changes in the botanical composition of the cover crop sod and in the time and method of cover crop control may help to reduce the competition for nitrogen between maize and the living mulch.     

A methodology for multi-objective cropping system design based on simulations. Application to weed management

Weeds are harmful for crop production but important for biodiversity. In order to design cropping systems that reconcile crop production and biodiversity, we need tools and methods to help farmers to deal with this issue. Here, we developed a novel method for multi-objective cropping system design aimed at scientists and technical institutes, combining a cropping system database, decision trees, the “virtual field” model FlorSys and indicators translating simulated weed floras into scores in terms of weed harmfulness (e.g. crop yield loss, weed-borne parasite risk, field infestation), weed-mediated biodiversity (e.g. food offer for bees) and herbicide use intensity. 255 existing cropping systems were simulated with FlorSys, individual indicator values were aggregated into a multi-performance score, and decision trees were built to identify combinations of management practices and probabilities for reaching performance goals. These trees are used to identify the characteristics of existing cropping systems that must be changed to achieve the chosen performance goals, depending on the user's risk strategy. Alternative systems are built and simulated with FlorSys to evaluate their multi-criteria performance. The method was applied to an existing oilseed rape/wheat/barley rotation with yearly mouldboard ploughing from Burgundy which was improved to reconcile weed harmfulness control, reduced herbicide use and biodiversity promotion, based on a risk-minimizing strategy. The best alternative replaced a herbicide entering plants via shoot tips (during emergence) and roots after barley sowing by a spring herbicide entering via leaves, introduced crop residue shredding before cereals and rolled the soil at sowing, which reduced the risk of unacceptable performance from 90% to 40%. When attempting to reconcile harmfulness control and reduced herbicide use, the best alternative changed the rotation to oilseed rape/wheat/spring pea/wheat, replaced one herbicide in oilseed rape by mechanical weeding, delayed tillage before rape and applied the PRE herbicide before oilseed rape closer to sowing. This option reduced the risk of unacceptable performance to 30%. None of the initial or alternative cropping systems succeeded in optimal performance, indicating that more diverse cropping systems with innovative management techniques and innovative combinations of techniques are needed to build the decision trees. This approach can be used in workshops with extension services and farmers in order to design cropping systems. Compared to expert-based design, it has the advantage to go beyond well-known options (e.g. plough before risky crops) to identify unconventional options, with a particular focus on interactions between cultural techniques.     

间套作资源集约利用及对产量品质影响研究进展

简要介绍了间套作对世界粮食安全的重要性,并对间套作领域当前主要的研究进展进行了综述与讨论。首先,综述了间套作复合群体在光能利用特性,指出了间套作可通过增强叶片光合性能和提高光的截获率与转化效率显著提高光能利用率。其次,综述了不同间套作复合群体在氮、磷、钾养分及水分利用等方面存在的竞争和互补利用现象,讨论了各种间套作类型资源高效利用的可能机制。最后,综述了间套作对产量和品质的影响。间套作可以使产量提高20%~50%,合理的种植密度和复合群体结构是高产的关键。不同间套作类型对秸秆和籽粒粗蛋白、粗纤维、粗脂肪、粗灰分及无氮浸出物等营养物质含量和产量的影响。通过以上几个方面的讨论,指出了间套作研究在资源集约利用、产量和品质等方面存在的不足和需进一步研究的问题。     

Designing cropping systems for efficient use of limited water in southern Australia

There has been continuous change in the systems of cereal production in southern Australia where the climate is semi-arid with moderately wet winters and hot dry summers. At the outset wheat (c. 1840) was grown in continuous culture as the land was gradually cleared for cropping, but yields declined to uneconomic levels by 1900. That system was then replaced with fallow-wheat rotations, and using phosphorus fertilizer, yields recovered, but not to the original level. From 1945, the high profitability of sheep production encouraged improvement of legume-based pastures and the introduction of pasture-crop sequences – ley-farming. Productivity was greatly increased and the yield of wheat crops regained the original level. But such were the rates of acidification and salinization of soil that reduced productivity and, in the case of salinity, reduced stream quality and threatened adjacent natural ecosystems. This ley-farming system was used until the late 1980s when prices for wool fell dramatically, and farmers reduced sheep numbers and intensified cropping. The thrust since then has been to design cropping systems that are economically as well as environmentally acceptable with salinity control as the major objective. There is now a search for systems that use more water to reduce drainage through the soil and lower saline water tables. A major contribution is the much restricted use of fallow but summer active plants are also required to provide a soil water storage buffer to retain autumn–winter rainfall. New systems under evaluation include herbaceous perennials such as lucerne that are readily integrated into a crop-livestock system and agroforestry combinations with various trees. The design and appropriate distribution of the new systems is aided by remote sensing techniques to locate areas of saline discharge and linkages to zones of groundwater recharge, geographical information systems to arrange the data for land system analysis, and computer models of crops and cropping systems. There is a substantial challenge for farmers, agronomists and others to identify and assess suitable new systems and to bring the public into the debate and into the solution.     

Creating the data basis to adapt agricultural decision support tools to new environments,land management and climate change—A case study of the RiceAdvice App

Increasing demand for land to ensure human food security in the future has already impelled agricultural production into marginal areas. The environmental conditions found there have a more pronounced impact on agricultural productivity than in the systems used so far under favourable conditions. In addition to this challenge, climate change is expected to increase the unreliability of weather conditions (through increased variability and occurrence of extremes) for farmers considerably. This unreliability is even more serious in developing countries’ farming system where food security is vulnerable. Current efforts in digitalization offer great possibilities to improve farmers` decision-making processes. A wide range of online tools and smartphone applications is available to support both agricultural extension services and smallholder farmers alike. These apps are often parameterized and validated to certain environments and are troubled when applied to new geographical locations and different environmental conditions. We have conducted field trials to demonstrate potential methods to close knowledge gaps in the data background for one of these apps, RiceAdvice, concerning three key aspects: shifting of cropping calendar, adjustment of fertilizer management and genotype selection. Sites in Ethiopia, Madagascar and Rwanda were selected to represent altitudinal gradients, with overlapping elevations reflecting differences in temperature to enable cross-country comparisons. Planting dates were distributed throughout three calendar years, with continuous iterative planting dates taking place in Madagascar, in- and off-season planting dates in Rwanda with different fertilizer applications, and one planting date during each rainy season in Ethiopia with different management options. With these trials, we have been able to identify key data sets needed for the adaptation of agricultural decision support tools to new environments. These include the assessment of climatic constraints on innovations to cropping calendars (e.g. double cropping), informed selection of alternative varieties able to complete crucial parts of their phenological development to avoid temperature-related stress inducing, for example spikelet sterility in rice in late development stages and the effectivity of potential innovations in fertilizer management strategies.     

基于农户调查的山地丘陵区玉米种植研究

为研究山地丘陵区农户玉米种植行为特征及农户扩大玉米种植意愿的决定因素,采用实地调研的方式,对山西省山地丘陵区的269户农户的玉米种植行为进行调研、分析,同时采用二元选择模型Logit模型对影响农户扩大玉米种植意愿的因素进行分析。分析结果表明,家庭耕地面积、农户玉米种植方式、玉米销售价格与扩大种植面积意愿呈正相关关系,玉米种植过程中的用工数量、资金投入数量、种植目的与扩大种植面积意愿呈负相关关系。为增加玉米播种面积、提高玉米产量相关部门应继续推进土地流转,加强玉米机械技术、种植技术的研发和推广,在稳定和降低农资价格,降低玉米生产成本的同时,健全玉米保护价制度,保障农户玉米种植的积极性。     

甘薯轮作与间作对根际土壤微生物群落的影响

为揭示土壤微生物群落对甘薯不同种植制度的响应机制,通过田间定位试验,设置甘薯连作、甘薯–小麦轮作、甘薯–玉米间作3个处理,采用磷脂脂肪酸（PLFA）和生态板（BIOLOG ECO）技术手段,研究了轮作与间作对甘薯根际土壤微生物群落结构、碳源利用能力的影响。结果表明,与甘薯连作处理相比,轮作与间作改变了土壤微生物主要类别的PLFA生物量,甘薯–小麦轮作与甘薯–玉米间作处理的细菌含量分别显著（P<0.05）增加21.82%和38.77%,放线菌含量分别显著增加6.98%和12.77%,革兰氏阳性菌生物量分别显著增加28.60%和63.44%,革兰氏阴性菌生物量分别显著增加18.21%和22.29%,真菌含量分别显著降低16.60%和13.03%;随着培养时间的延长,甘薯–玉米间作处理的平均颜色变化率（AWCD值）显著高于其他2个处理,甘薯–玉米间作处理对羧酸类化合物、多聚化合物、碳水化合物、氨基酸化合物和胺类化合物的利用能力较甘薯连作处理分别显著增加17.28%、14.67%、54.17%、36.62%和20.00%;冗余分析（RDA）结果表明,土壤微生物群落结构及功能多样性的变化受多种因素共同影响,土壤速效钾和全氮为主要驱动因子;甘薯–小麦轮作与甘薯–玉米间作在一定程度上均可优化土壤微生物群落结构,提升微生物功能多样性,其中甘薯–玉米间作处理效果较好。     

长期连作和轮作对农田土壤生物学特性的影响研究进展

土壤生物学特性作为衡量土壤质量的重要指标,可以表征土壤质量演变趋势,不同种植制度对土壤生物学特性的影响不同。通过综述国内外连作、轮作等种植方式下土壤生物学特性的研究进展,重点分析了连作和轮作对土壤微生物、土壤线虫和土壤酶活性的影响,指出合理种植制度对土壤质量修复的可能性及研究方向,提出集约化农田种植制度优化策略,为制定合理的种植制度和农业的可持续发展提供参考依据。