中国林木施肥与营养诊断研究现状

养分供给是林木生长发育的物质基础,树体营养元素浓度与林木生长量、产量有密切的关系,它是林木施肥与营养诊断的理论基础。植物必须通过合理施肥,使树体营养元素浓度保持适当的水平与比例,才能实现稳产、高产的目标。本文对我国林木施肥方法、施肥时间、主要用材林树种施肥效应与营养诊断研究现状进行了评述,并对此提出了自已的一些观点和建议。     

中国林木施肥与营养诊断研究现状

养分供给是林木生长发育的物质基础,树体营养元素浓度与林木生长量、产量有密切的关系,它是林木施肥与营养诊断的理论基础。植物必须通过合理施肥,使树体营养元素浓度保持适当的水平与比例,才能实现稳产、高产的目标。本文对我国林木施肥方法、施肥时间、主要用材林树种施肥效应与营养诊断研究现状进行了评述,并对此提出了自已的一些观点和建议。     

广西八角养分评价标准研究

通过对八角(Illicum verum)施肥前后的土壤及植株叶片进行分析测定，掌握施肥前后土壤及植株叶片的养分变化规律，并根据施肥前后八角生长与开花结果等情况，总结出八角林地土壤与植株叶片各种养分的丰缺指标，为八角的平衡配方施肥提供科学依据。     

油茶配方施肥技术研究进展

林木施肥是提高土壤肥力、改善林木营养状况和促进林木生长,达到优质、高产的重要营林措施之一。油茶必须通过合理施肥,使树体营养元素浓度保持适当的水平与比例,才能实现稳产、高产的目标。对我国油茶施肥技术及研究方法进行了评述,并探讨今后研究的方向,为油茶科学施肥提供理论依据。     

八角老林施肥效果好

文山州有八角成林十万余亩,常年产量二百至三百万斤,平均亩产仅二三十斤。单产低的原因主要是老林比例大,不施肥。为了迅速提高八角老林的产量,文山州八角科研所从1983年开始进行施肥试验,结果表明,秋后施肥的老龄八角树有延寿、增产等收效。 1.投资小,收效大,见效快。根据多点试验结果,每株树一般施肥一斤左右,秋后能增收二至五斤干八角,即一株树春天收入二角五分钱,秋后即可增收七元左右,群众说这是“一本万利”的事。     

施肥对不同杨树防御酶活性的影响

杨树对土壤营养条件反应十分敏感,在各种栽培措施中,以施肥的效果较为显著。氮肥是杨树矿质营养的主要限制因子,对植物生长及体内的生理生化有显著影响。可以通过影响昆虫的寄主植物,间接的影响昆虫弄清土壤与杨树之间营养元素供需关系及杨树生长特性和其寄生害虫的直接密切关系具有重要意义,为此,以光照和施肥对杨树的影响为研究对象,开展了室内控制实验和田间施肥试验,为杨树的广泛扩大培育和配方施肥以及杨树的抗性研究提供重要的依据。     

八角施肥产量高

八角树结的果实叫八角,其味芳香醇甜,有兴奋作用,可供调味、入药和轻化工原料等用,经济价值高,国内外市场需量很大。当前,市场上八角供应紧缺,解决这一问题最有效的办法,一是积极营造新林二是对现有老林加强管理,追施肥料,以增加产量。追施肥料以后八角能增产。去年四月份,我们在富宁县的坡地、团堡、龙坪等村部分八角林内作施肥试验,秋收时作过秤对比,结果凡施过肥的八角鲜果都比未施肥的重8     

红松人工林土壤肥力指标的研究

立地条件的优劣是关系到红松造林能否成林的重要因素,特别是土壤的理化性质及其营养元素的水平,直接影响到红松人工林的生长发育。本文试图通过调查分析,探讨不同年龄阶段红松人工林下土壤中各种养分元素的变化规律,从而找出不同年龄阶段内红松人工林下土壤的营养元素的变化趋势,为红松人工林经营和林地施肥提供科学依据。     

油茶林地和树体内营养元素变化研究

为了探索油茶林地和油茶树体内营养元素变化规律，掌握有效的施肥量，提高油茶产量，我们在油茶产区永兴县选定了１２块不同立地类型的油茶林标准地，通过一年的连续采样，测定土壤和树体内Ｐ，Ｋ，Ｃｕ，Ｍｎ，Ｚｎ，Ｆｅ，Ｍｇ等元素的含量，分析了它们的变化规律，对林地施肥有一定的指导作用。     

杨树二耕土施肥肥效的研究

通过湖南省围堤湖农场二耕土三年施肥试验表明：在二耕土施肥第一年对杨树树高生长效果不明显，第二、三年施肥效果明显，单施氮肥树高生长增加１５％～２０％，胸径生长增加１８％～２０％；氮磷肥配合使用树高生长增加１５％～１９％的胸径生长增加１７％～２１％。试验证明施肥可以提高土壤肥力，调节树体内营养元素的平衡，促进树高和胸径的生长。本研究成果对促进二耕土杨树速生丰产具有十分重要的实践意义。     

不同八角优株果实的茴香油含量及其化学组成分析

采用水蒸气蒸馏法对云南省林业科学院经济林研究所选育的10个八角优良单株八角果实的茴香油含量作了测定,并运用气-质联用仪对其所提取的茴香油的组成进行了分析。结果表明:八角各优株果实茴香油的含油率达7.9%~16.4%,其变异系数为22.86%,均超过了云南所拟定的八角优株的该项选优标准;其茴香油中主要含反-茴香脑,相对含量达80.51%~96.47%,其次为草蒿脑、顺-茴香脑等化学物质。     

Modified exponential nitrogen loading to promote morphological quality and nutrient storage of bareroot-cultured Quercus rubra and Quercus alba seedlings

Abstract

Exponential nutrient loading has been used to improve nursery fertilizer uptake efficiency of conifer seedlings, but the technique has received little attention in the culture of temperate deciduous hardwoods. This study examined responses of northern red oak (Quercus rubra L.) and white oak (Q. alba L.) seedlings to modified exponential nitrogen loading during bareroot nursery culture using a broad range of nutrient supply from 0 to 3.35 g nitrogen (N) per plant per season for 18 weeks in Indiana, USA. Seedling growth and nutritional parameters followed a curvilinear pattern that ranged from deficiency to toxicity with increased fertilization consistent with trends depicted in the proposed model for nutrient loading. Fertilization increased plant dry mass by 113–260% for red oak and 49–144% for white oak. Severe nutrient deficiency occurred under indigenous soil fertility, and limited phosphorus and potassium uptake were found to inhibit seedling growth at higher N supply. The sufficiency and optimum rates were determined to be 0.84 and 1.68 g N per seedling per season, respectively, under the current cultural conditions. Fertilization at 1.68 g N per plant increased N content by 40% in red oak and 35% in white oak. This approach may be used to help refine nursery fertilization practices in hardwood culture to produce high-quality seedlings for field planting.     

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.     

磷施肥水平对油茶植株营养生长的影响

为了提供科学合理的施肥依据,在氮、钾肥最佳用量的基础上,依次设置5个磷水平处理,对油茶幼林开展施磷肥试验。结果表明:低于每年900 g/株磷肥水平时,油茶植株的株高、地径、冠幅乘积增幅、叶绿度、叶面积及叶片养分N、P、K随着磷素供应水平的增加而增大;在每年900 g/株磷肥水平下,各项指标达到最大值;大于每年900 g/株磷肥水平时,各项生长指标没有增加反而降低了。说明过度施入磷肥,导致植株磷肥利用率的降低,影响植株体内干物质积累,不利于植株生长;不同磷水平处理中,对油茶各指标的影响呈先增大后减少的趋势。叶片养分与油茶树体指标间呈极显著相关性,施磷肥与各项指标关系密切。油茶植株营养生长对磷水平的响应,说明合理施用磷肥有利于油茶植株树体的生长和叶片养分的累积。     

八角的遗传多样性与良种选育

就我国八角的遗传多样性与良种选育进行了分析,并提出了今后我国八角良种遗传改良的方向．认为我国八角栽培历史悠久,在自然选择下,其树形、分枝习性、叶、花、果实等方面出现了明显的差异性,遗传多样性丰富．目前,只有广西和云南进行了果用林优树选择,广西共选出128株优树,云南共选出18株优树;叶用林优良品种选育跟不上现实的需要．今后八角的良种选育将以优树选择为主,积极开展杂交育种,采取常规育种技术与生物技术相结合的育种技术以培育新的品种．     

林木苗期营养诊断与施肥研究进展

林木苗期营养诊断与施肥研究对于指导培育壮苗、提高苗木质量和造林成活率至关重要。文中详细介绍了形态分析、植物组织分析、生理生化分析等几种主要的林木营养诊断方法在国内外林木苗期诊断试验中的应用情况, 从施肥方式、施肥量以及元素配比等方面对国内外林木苗期施肥研究进行总结, 并展望未来林木苗期营养诊断与施肥研究的发展方向。     

林木施肥与营养诊断

70年代以来,林木施肥与营养诊断,在恢复提高人工林林地肥力方面取得了很大进展,合理施肥已成为定向培育短轮伐期工业用材林重要技术措施。开展系统施肥网营养诊断研究是进行合理施肥、提高肥效的前提。土壤分析、植物组织分析与田间试验是主要营养诊断手段,由于诊断方法还存在一些技术问题,故在指导林地施肥方面尚受一定限制。本文对林木施肥研究历史、生产应用趋势和有关问题作了扼要评述。应用综合环境因子来研究营养诊断,开展系统定位试验,制定按树种的合理施肥方案。     

欧洲花楸组织培养中缺素症状的研究

通过改变培养基配方对欧洲花楸进行缺素症状的研究,旨在为生产试验中直观判断培养基养分的丰缺情况,以便为及时改变适合植物生长的培养基配方提供理论依据。实验结果表明:最早出现缺素症状的是缺镁培养,其次是缺钙培养和缺铁培养。     

Exponential nutrient loading: a new fertilization technique to improve seedling performance on competitive sites

Reforestation efforts in Ontario have become increasingly more reliant on containerized planting stock since these seedlings are less costly to produce and plant than bare-root stock. Container seedlings, however, tend to be more susceptible to competing vegetation when planted on weed-prone sites often requiring release by chemical herbicides. We have developed cultural techniques to improve the competitiveness of containerized seedlings by promoting initial outplanting performance thus reducing the need for early vegetation control. The approach is based on two new preconditioning practices, exponential fertilization and nutrient loading, which induce a steady-state build up of nutrient reserves in seedlings for outplanting. Exponential nutrient loading integrates these practices with high dose fertilization inducing luxury consumption. Steady-state culture corresponds better with the competitive outplanting environment, since stable internal nutrient accumulation in the greenhouse phase conforms with steady-state nutrient uptake of natural exponentially growing vegetation in the field, and exponential nutrient delivery to container-restricted root systems also better simulates nutrient flux reached by expanding roots in a field soil with constant nutrient availability. Combined with nutrient loading, the higher nutrient reserves and improved nutrient balance in seedlings contribute to enhanced stress resistance and increased growth performance. This paper reviews the theory and practice of exponential nutrient loading during seedling culture, presents results of growth and nutritional responses of seedlings planted on competitive sites, and suggests appropriate criteria for quality testing of nutrient loaded stock.