苗木施肥技术及其发展趋势

立足于苗木施肥的主要理论, 从施肥种类、施肥量、施肥时期和施肥方式等方面对苗木施肥技术作了较为系统的阐述, 并指出平衡施肥、计算机推荐施肥、研制苗木专用肥、苗木定向培育施肥研究等是今后苗木施肥技术的发展趋势, 为制定科学的苗木施肥方案、提高肥料的利用效率、完善林木抚育管理技术等提供理论支撑和科学指导。     

林木施肥技术研究进展

系统地阐述了当前林木施肥技术研究的现状；介绍了该领域出现的各种肥料种类、施肥方式以及施肥方法，并展望了施肥技术研究的趋势。     

林木苗木平衡施肥研究进展

本文综述了林木苗木平衡施肥研究的现状,平衡施肥的概念、技术和作用,平衡施肥的理论依据,平衡施肥技术及施肥效应,并对平衡施肥的前景和发展方向进行了展望。     

毛竹林施肥研究进展

施肥是提高毛竹林经营效益的最有效手段之一。我国在毛竹林施肥研究方面,特别是在施肥量的计量、肥料种类以及施肥技术上取得了显著成就,但在生产实践中仍存在着盲目施肥、环境污染等问题。本文综述了毛竹林施肥研究的现状,分析了毛竹林施肥中存在的问题,并为毛竹林科学施肥提出了建议。     

杨树营养及施肥研究进展

施肥是杨树速生丰产林建设的关键技术。在阐述杨树养分特性和养分诊断技术的基础上, 分别从施肥效应及其影响因素和施肥技术方面综述了20世纪50年代以来的国内外杨树施肥研究, 并提出3点建议:形成适于不同区域、不同土壤类型和不同品种无性系的施肥技术体系; 注重和加强淋溶、水肥耦合等施肥机理的研究; 借鉴农业先进施肥技术, 摸清杨树与土壤的养分供求关系, 实现林业精准施肥。     

毛竹计量施肥研究进展

综述了近５０年来国内外毛竹计量施肥研究的进展，阐述了毛竹施肥的各种计量才毛竹高产施肥技术，探讨了当前我国毛竹施肥存在的问题，指出了毛竹施肥的发展趋势，提出了加强竹林管理，合理施肥的对策，这对当前方兴未艾的毛竹低产林改造具有重要意义。     

不同施肥措施对毛金竹新竹产量的影响

对毛金竹天然林和人工林进行施肥试验,研究不同施肥方式（竹腔施肥、土壤施肥以及复合施肥）对竹林产量的影响。结果显示,无论是人工林分还是天然林分,施肥措施均能有效提高林分的产量指标,其中复合施肥（竹腔+土壤施肥）效果最好,产量指标明显高于其他处理。     

人工林施肥研究进展综述

文章综述了人工林施肥的研究进展概况，包括林木施肥的理论基础、肥料种类和施肥方式、林木施肥效应及其影响因素、林木施肥方法，最后展望了林木施肥的发展方向。     

泡桐速生丰产施肥技术研究进展

综述了近几十年来我国泡桐林施肥技术的研究概况,理清了未来的研究热点和方向,重点阐述了林木配方施肥的理论基础及立地养分效应配方施肥模型。综合国内外现有研究成果,提出了建立泡桐林施肥基础数据库、减小林木施肥所造成的环境污染、实现环境保护的新观点,并指出我国泡桐速生丰产林施肥的发展方向是按立地类型、分生长阶段的目标产量及效益下的测土配方施肥。     

油茶林施肥效应研究概述

油茶是我国特有的木本油料树种,分布广泛,栽培历史悠久。近年来,我国非常重视油茶林的经营管理,不断地由粗放经营向高效经营管理转变,施肥作为油茶重要的管理措施,对油茶有明显的增产、增益效果。综述分析了油茶林施肥对油茶生长指标、经济性状、生理特性以及土壤性状的影响,总结油茶施肥方法,并探讨今后研究的方向,为油茶科学施肥提供理论依据。     

Assessing the effect of late-season fertilization on Holm oak plant quality: insights from morpho–nutritional characterizations and water relations parameters

Forest restoration projects with Holm oak (Quercus ilex) have had limited success, mostly due to water stress after planting and poor plant quality. Recent studies indicated that large and nutrient rich plants perform better in Mediterranean areas, suggesting that late-season fertilization may improve plant quality and field performance. The purpose of this study was to assess the effect of late-season fertilization on the quality of Holm oak seedlings, as determined by morphological, nutritional, and water relations analyses. We grew Holm oak nursery seedlings under 5 different late-season fertilization regimes and then analyzed morphological characteristics, nutritional status, and water relations parameters of the fertilization groups at the end of the nursery period. We also analyzed the effect of fertilization on nutritional status by use of vector nomograms. Our results indicated that late-season NPK fertilization improved shoot and root growth, and the overall nutritional status of seedlings. The lack of late-season fertilization leads to nutrient deficiency in plants, whilst the application of imbalanced fertilization treatments may trigger nutrient luxury consumption and nutrient dilution, pointing out the importance of NPK proportions in the fertilizer. Moreover, late-season fertilization with nitrogen might improve the drought resistance of seedling by enhancing their osmotic adjustment.     

益生菌肥料在桉树人工林可持续发展中的应用

为促进林木生长,减少化学肥料使用,保护环境,维护地力,本研究从林木根际分离植物益生菌,经系统试验,筛选出一批对桉树生长具有明显促进作用的优良菌株。其中的 DU07菌株兼具固氮、解磷、解钾功能,被研制成菌剂、有机菌肥、益生菌复合肥。菌剂接种桉树苗木的育苗和造林试验覆盖广西桉树大部分栽培区。在广西高峰林场建立的146.2 hm2示范林,18月龄林木平均树高达11.16 m,胸径7.38 cm,均分别高于对照,起到了良好的示范作用。不含无机氮素的有机菌肥在试验初期的肥效较慢,但半年后,菌肥处理的林木胸径、树高均超过对照,其肥效显示长效缓释作用;施用菌肥的桉树根区土壤微生物、尤其是固氮菌数量明显增多,土壤酶活性均有不同程度的提高。无机有机益生菌复合肥总养分≥15%,比总养分≥30.0%的对照肥减少一半,然而1.5年生试验林的树高和胸径均分别高于对照,土壤的速效氮、磷、钾也均高于对照。表明益生菌肥有利于土壤中各种物质的分解和转化,在改善土壤状况和维护地力上具独特作用。这对于在生产中减少无机化肥的使用,保护土壤环境具有重要的现实意义。     

Growth of Nursery-grown Bamboo Inoculated with Arbuscular Mycorrhizal Fungi and Plant Growth Promoting Rhizobacteria in two Tropical Soil Typeswith and without Fertilizer Application

A nursery experiment was conducted to assess the effect of bioinoculants (Glomus aggregatum, Bacillus polymixa, Azospirillum brasilense) on seedling growth promotion of bamboo (Dendrocalamus strictus (Roxb.) Nees.) in two soil types (alfisol, vertisol) with or without fertilizer application. Bamboo seedlings were grown in the presence or absence of bioinoculants either individually or in all combinations for 180 days in field soil under tropical nursery conditions. Shoot, rhizome and root length, dry masses, nutrient concentrations and arbuscular mycorrhizal (AM) colonized root lengths were determined at harvest. Under the experimental condition tested combined inoculation of AM fungi, PSB and A. brasilense resulted in maximum growth response both under fertilized and unfertilized conditions in both soil types. Fertilizer application enhanced the efficiencies of N, P and K uptake, whereas reduced their usage efficiencies. Though soil type did not affect microbial inoculation response, fertilizer application significantly affected plant response to microbial inoculation.     

Fall fertilization of Holm oak affects N and P dynamics,root growth potential,and post-planting phenology and growth

• Introduction   

For Holm oak (Quercus ilex L.), a flush growing species, nutrient loading during the growing season is difficult and can lead to a low nutrient status of the seedlings. To provide insights about Holm oak nutrient dynamics during fall in the nursery and subsequent planting performance, a factorial nursery experiment was conducted in a mild fall–winter area testing the effects of timing of fertilization (early and late fall) and rate (two doses of a NPK fertilizer that applied 28 and 56 mg N per seedling), followed by an experimental plantation.     

Premature shoot growth termination allows nutrient loading of seedlings with an indeterminate growth strategy

Nutrient loading of nursery seedling stock of species with an indeterminate growth strategy is challenging and poorly understood. Here, we explore the use of two potential techniques for nutrient loading of trembling aspen (Populus tremuloides Michx.) seedlings: (1) exponential fertilization and (2) early shoot growth termination in order to divert assimilated nutrients and carbon to storage rather than to growth. In the first study, aspen seedlings were treated with either exponential or constant fertilization rates, both of which supplied the same amount of nutrients over the growing season. Exponential fertilization resulted in overall poor planting stock form (stunted seedling growth and weak root development) and produced only marginal improvements of nutrient status. As a result, the exponential fertilization regime studied cannot be recommended as a treatment for aspen seedlings. In the second study we treated seedlings with a 2 × 2 factorial combination of fertilization and shoot growth inhibitor (SGI) applications with the fertilizer treatments varying in terms of mid-season fertilizer concentrations. Seedlings with SGI application had much higher tissue nutrient and carbon reserve concentrations than seedlings without a SGI application. In addition, nutrient uptake appeared to be more efficient in SGI treated seedlings, which could potentially result in significant reductions of nutrient application rates during aspen seedling production in nurseries. Overall, early shoot growth termination using a SGI appears to be an effective technique to produce nutrient loaded aspen seedlings.     

Growth regulation of Scots pine seedlings with different fertilizer compositions and regimes

Scots pine (Pinus sylvestris L.) seedlings were grown in containers filled with peat, using two different fertilizers and three different fertilizer regimes. Seedling shoot and root growth and shoot content of nitrogen, potassium and phosphorus were followed in the nursery and after outplanting in the field. Attempts to regulate growth rate by an exponential nutrient supply were not successful, but the root/shoot ratio was influenced by the fertilization regime. Internal nitrogen concentration was stable only for seedlings with low relative growth rate, while seedlings with high nutrient supply in the nursery showed strong nutrient dilution in the shoot after planting.     

Fertilization Response on Growth,Photosynthesis, Starch Accumulation,and Leaf Nitrogen Status of Cassia siamea Lam. Seedlings Under Nursery Conditions

Abstract

Nitrogen, phosphorus, and potash fertilizers in eight treatment combinations, including an unfertilized control treatment were given to Cassia siamea seedlings under nursery conditions. This study was carried out to identify the physiological basis of varying growth response due to fertilization. Nitrogenous fertilizer application increased seedling growth, whereas application of phosphorus or potash fertilizers, either separately or in conjunction, did not improve seedling growth. Starch level had increased considerably whenever there was decline in the leaf nitrogen status, even though the photosynthetic rate was reduced drastically. Starch concentration remained significantly higher in leaves of seedlings which showed poor growth because of treatment effects. Vector analysis of nitrogen concentration, content, and dry mass allowed simultaneous comparison of leaf nitrogen status. This analysis showed that nitrogenous fertilizer application signified dilution effect. P-fertilizer application alone leads to N-deficiency and in PK-fertilizer application, vectors shifted into a region of antagonistic effect. These results are useful in evaluating woody seedlings growth response due to fertilizer management under nursery conditions.     

兰考泡桐根插苗的生长和营养状况的研究

通过盆栽试验,研究了兰考泡桐根插苗的生长和盆土营养物质的变化。着重分析苗木生长、体内营养状况、营养物供应及盆土矿质养分释放的相互关系;苗木按比例吸收N、有效P和Mg等各种营养物的特点。提出培养壮苗应用最适营养物比例适当调整圃地土壤进行配比施肥的设想。从树木营养生理角度,论证科学施肥的重要性。     

A strategy for tree-perennial crop productivity: nursery phase nutrient additions in cocoa-shade agroforestry systems

Shade tolerant species response to nutrient additions and light regulation by canopy trees in perennial agroforestry systems has been well documented. However, accelerated early growth, particularly in cocoa-shade systems, may be offset by competition for limited resources on nutrient poor sites. To date, few agroforestry management strategies focus on nutrient manipulation of the shade tree component or strategies for precision nutrient application. Our research objective was to diagnose interactions between nutrient supplied shade trees intercropped with cocoa. We established greenhouse trials in Kwadaso, Ghana cultivating Terminalia superba seedlings with four fertility treatment levels: conventional rate (current practices) under linear additions, and half, full and double conventional rate under exponential additions (steady-state nutrition) to determine maximal growth and nutrient uptake. After 4 months of additions in the nursery, pre-fertilized T. superba seedlings were then out-planted into field trials with cocoa seedlings. After 4 months of intercropping, cocoa associated with half rate exponentially supplied T. superba had significantly larger leaf area, greater leaf number, and higher nutrition (N and P uptake) than cocoa associated with full rate conventionally supplied T. superba. This may be attributed to (1) more favorable light conditions under these taller shade seedlings and (2) the internal use of nutrients associated with exponentially supplied T. superba seedlings, which lowered stress on native soil resources. The latter is corroborated with our findings on soil fertility status. This strategy focused on reducing fertilizer inputs and developing precise plant nutrition technology for on-farm use. Our findings suggest that shade seedlings under steady state nutrition can mitigate early growth competition in the field.     

Organic matter amendments to a calcareous forest nursery soil

Organic amendments were added to a southwestern United States forest nursery sandy loam soil to determine the effects on soil nutrient reserves and subsequent growth of 1.5+0 ponderosa pine (Pinus ponderosa Laws.) seedlings. Treatments included irradiated sewage sludge, peat moss and pine bark each at 67 t/ha, sawdust at 43 t/ha, and a control that received no organic matter. Sludge caused immediate increases in soil nutrients, especially N and P. Sawdust resulted in near complete N immobilization 45 d after application. Peat moss and bark did not significantly alter soil nutrients. All treatment effects disappeared within 6 months of application.Amendments did not significantly alter seedling survival, biomass or yield (caliper 3 mm). Seedling biomass was positively correlated with early soil nutrient status, but growth was not significantly improved. The modest, short-term nutritional benefits indicate single applications of organic amendments are ineffective in improving the nutrient status of sandy nursery soils of the Southwest.