Nutrient Distribution and Stem Length in Flowering Stems of Protea Plants

A study of nutrient distribution in the flowering stem of proteas was carried out in commercial protea plantations of each of the cultivars ‘Scarlett Ribbon’, ‘High Gold’, ‘Veldfire’, and ‘Sunrise’ of Leucospermum cordifolium, and of the species L. patersonii located in a subtropical zone (La Palma Island, Canarian Archipelago). Flowering stems were cut into different parts: flower bud, leaves from half proximal stem to the flower bud, leaves from half distal stem to the flower bud, half proximal stem to the flower bud, and half distal stem to the flower bud. Nutrient content of the different parts of the flowering stems of the cultivar and the species gave significant differences in some cases, depending on the nutrient and the cultivar. Occasional dissimilarities among the levels of nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), sodium (Na), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) were determined in comparisons among half proximal stems and half distal stems, independent of the cultivar. The same trend was observed when nutrient contents of the leaves from the half distal and the half proximal stems were compared. Phosphorus exhibited the lowest concentrations of all macronutrients in the different organs. Flower buds presented the smallest levels of macro-and micronutrients, while the leaves of the half distal and half proximal stems showed the highest values. The influence of nutrients of leaves from the half proximal stems on the stems length varied among cultivars.     

西藏土壤磷素和钾素养分状况及其影响因素

探讨西藏土壤磷钾养分状况及其影响因素.结果表明西藏土壤全磷和全钾主要决定于母质.此外,土壤全磷与有机质呈正相关,故表层全磷高于底层,表现磷的生物表聚作用;而全钾与有机质呈负相关,故表层全钾低于底层,表现为有机质对钾的"稀释效应".表层速效磷(Olsen-P)＜10 mg/kg 的缺磷土壤面积约占78%,表明下层速效磷更低.土壤速效磷与全磷、有机质的关系复杂,而与pH的关系密切,一般在pH 6.4～7.3的土壤中含量较高.西藏土壤表层速效钾100～150 mg/kg 和＞150 mg/kg 的面积分别占17%和66%;并且速效钾主要决定于CEC,进而决定于有机质,而与粘粒关系不明显,与全钾无关.     

昆山市土壤养分现状与变化趋势研究

2009年对昆山市土壤养分进行检测,检测结果显示：有机质35.5 g·kg-1,全氮2.22 g·kg-1,碱解氮162 mg·kg-1,有效磷15.1 mg·kg-1,速效钾115 mg·kg-1,pH值6.0。与第二次土壤普查相比,有机质和全氮含量呈上升趋势,碱解氮、有效磷、速效钾含量明显提高,pH值呈下降趋势。     

Soil Nutrient Status and Leaf Nutrient Norms in Oil Palm (Elaeis Guineensis Jacq.) Plantations Grown in the West Coastal Area of India

Oil palm (Elaeis guineensis Jacq.) is a heavy feeder of nutrients and requires balanced and adequate supply of nutrients for optimum growth and yield. Information regarding soil nutrient status and leaf nutrient concentration is very much required for proper fertilizer application. Therefore, a survey was conducted for assessment of soil nutrient status and leaf nutrient concentration in 64 oil palm plantations in the state of Goa lying in the west coastal region of India. Soil pH, electrical conductivity (EC), organic carbon (OC), available potassium (K) (ammonium acetate-extractable K) (NH₄OAc-K), available phosphorus (P) (Bray’s-P), exchangeable calcium (Ca) (Exch. Ca) and magnesium (Mg) (Exch. Mg), available sulphur (S) (calcium chloride-extractable S) (CaCl₂-S), and hot water soluble boron (B) (HWB) in surface (0–20 cm depth) soil layers ranged from 4.25 to 6.77, 0.05 to 1.06 dS m^–1, 5.07 to 48.4 g kg^–1, 58.1 to 1167 mg kg^–1, 1.80 to 415 mg kg^–1, 200 to 2997 mg kg^–1, 36.0 to 744 mg kg^–1, 3.00 to 87.7 mg kg^–1 and 0.09 to 2.10 mg kg^–1, respectively. Diagnosis and Recommendation Integrated System (DRIS) norms were established for different nutrient expressions and were used to compute DRIS indices. As per DRIS indices, the order of requirement of nutrients in the region was found to be P > Mg > K > nitrogen (N) > B. Optimum leaf nutrient ranges as per DRIS norms varied from 1.64 to 2.79%, 0.36 to 0.52%, 0.37 to 0.75%, 0.89 to 1.97%, 0.35 to 0.63%, 0.89 to 1.50%, 3.10 to 13.9 mg kg^?1, 7.50 to 32.2 mg kg^?1, 35.0 to 91.1 mg kg^?1, 206 to 948 mg kg^?1, and 895 to 2075 mg kg^?1 for N, P, K, Ca, Mg, S, B, copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) respectively. On the basis of DRIS-derived sufficiency ranges, 14, 5, 11, 6, 6, 6, 8, 2, 3, 6, and 16% of leaf samples had less than optimum concentrations of N, P, K, Ca, Mg, S, B, Cu, Zn, Mn, and Fe respectively. The optimum ranges developed can be used as a guide for routine diagnostic and advisory purpose for balanced utilization of fertilizers.     

Study of Soil Fertility and Plant Nutrition of Proteas Cultivated under Subtropical Conditions

Abstract: A study of soil physicochemical characteristics and mineral nutrition of four cultivars of Leucospermum cordifolium (‘Scarlett Ribbon,’ ‘High Gold,’ ‘Veldifre,’ ‘Sunrise’) and Leucospermum patersonii species was carried out along 2 years in commercial protea plantations, distributed throughout a subtropical region (La Palma Island, Canarian Archipelago). Soils presented a slightly acid pH range, whereas organic matter showed suitable values. Generally, available soil phosphorus (P) contents were less than 25 mg kg^?1, with high available potassium (K) and calcium (Ca) levels, though the ratio of Ca of the sum of available cations was usually appropriate. Despite the high electrical conductivity (EC) levels (4.31–8.87 dS m^?1) determined in some soils, no salinity symptoms were ever detected. Distribution and behavior of foliar nutrients nitrogen (N), P, K, Ca, magnesium (Mg), and sodium (Na) along time showed that nutritional needs varied in some cases among cultivars and species. L. patersonii presented the least N concentration, whereas ‘High Gold’ and ‘Veldfire’ had the greatest levels. Data denoted that P requirements were larger in younger plants, during the recovery after pruning, and while new buds developed. ‘Sunrise’ cultivar stood out for its large foliar levels of P, whereas ‘Scarlett Ribbon’ and ‘Veldfire’ had the least K contents. As a general pattern, K decreased in winter samplings. L. patersonii species and the cultivar ‘Sunrise’ exhibited the highest Ca values, and the same was true for Mg only in the species. A special need for Na appeared in all the cultivars and species studied. L. patersonii and the cultivar ‘Sunrise’ showed the greatest Na levels. A general stabilization of nutrient concentrations was observed in the fourth, fifth, and/or sixth samplings, so that November is recommended for taking samples for current foliar analysis. In this context, foliar ranges for the studied nutrients are suggested.     

黄瓜有机营养土栽培中土壤酶活性、肥力动态变化及其相互关系

稻草与土按1:1(处理A)、2:1(处理B)的比例混合,经过堆积高温腐熟后在日光温室中栽培黄瓜,试验结果表明:有机营养土中稻草比例高的,脲酶、转化酶、纤维素酶活性升高,碱解氮、速效P、速效K含量增加,分别是处理B>处理A>对照,但过氧化氢酶活性呈降低趋势,变化大小为对照>处理A>处理B。脲酶、转化酶和纤维素酶与速效P呈极显著相关,与速效K显著相关。碱解氮含量与脲酶极显著性相关,与纤维素酶和转化酶显著性相关,但过氧化氢酶活性与碱解氮、速效P、速效K含量呈负相关,因此脲酶、转化酶、纤维素酶活性可以作为评价有机营养土肥力的标准。     

喀斯特地区不同茎形态植物的水土保持和养分截留效果研究

在坡度为30°的坡地建立12个径流小区,试验设计4个处理,分析了3种不同茎形态植物的水土保持和养分截留效果,并在此基础上进一步探讨水土保持和养分截留之间的定量关系。结果表明:薜荔,马蔺和常青藤的覆盖度分别为53.1%,62.8%和60.0%。薜荔,马蔺和常青藤具有一定的水土保持效果,不同植物的保水固土效应存在显著性差异。薜荔,马蔺和常青藤对TP,DP,TN,NO₃^--N,NH₄⁺-N和K有一定的截留作用。薜荔对TP,DP,TN,NO₃^--N,NH₄⁺-N和K的截留效果分别为0.58,0.64,0.54,0.86,0.64,0.54;马蔺对TP,DP,TN,NO₃^--N,NH₄⁺-N和K的截留效果分别为0.76,0.64,0.68,0.78,0.53,0.56;常青藤对TP,DP,TN,NO₃^--N,NH₄⁺-N和K的截留效果分别为0.72,0.75,0.61,0.83,0.45,0.58。水土保持与养分截留效果之间呈现极显著性相关（Pearson相关性系数 > 0.698^**）,表明水土保持是养分截留的有效途径。     

西藏人工造林作业区土壤养分特征研究

为了掌握西藏拟造林作业区的土壤养分状况,对6个地市524个造林作业区的土壤样本进行了养分测定和分析。结果表明:(1)土壤全钾、有效磷、有机质和速效钾均处在"稍缺―极缺"水平:平均含量分别为6.26 g kg~(-1)、8.7 mg kg~(-1)、17.81 g kg~(-1)和83.6 mg kg~(-1),全氮和全磷处在"中等―稍缺"水平:平均含量分别为1.39 g kg~(-1)和0.72 g kg~(-1),碱解氮条件最好:平均含量为214.1 mg kg~(-1),全钾条件最差。(2)6地市除碱解氮外,土壤中分别存在2至5个养分元素的缺乏,多数作业区全钾、速效钾和有效磷不足。阿里地区最缺有机质,仅5.08 g kg~(-1),日喀则市、拉萨市和林芝市最缺全钾,仅5.19~6.42 g kg~(-1),山南市和昌都市最缺有效磷,仅3.9~5.4 mg kg~(-1)。此外,拉萨市、山南市和阿里地区多数作业区全氮不足,阿里地区、日喀则市和昌都市全磷不足,除昌都市外各地市有机质不足的作业区居多。(3)地市间土壤养分含量差异显著,但速效钾、有机质在日喀则市、拉萨市和山南市间差异均不显著。总体而言,西藏造林作业区土壤养分状况较差,通过对西藏造林作业区土壤养分的特征分析,可为作业区造林后树木生长状态的成因查寻提供科学依据,为进一步提高造林质量提供基础数据。     

作物有效营养面积及最佳营养面积研究

通过无肥区和施肥区不同土壤营养面积的试验得出 :黑土垄作区甜菜的有效营养面积是 3 7.8～ 5 3 .4× 67cm ;最佳营养面积是 2 7.3～ 2 9.7× 67cm。无肥区植株有较小的有效营养面积和最佳营养面积 ,施肥区植株有较大的有效营养面积和最佳营养面积。土壤营养面积过小 ,个体生长影响较大 ,会改变其生物学生长规律 ,S型生长曲线不明显     

平朔矿区开采受损及治理区土壤养分特征对比分析

[目的]了解山西省朔州市平朔矿区土壤养分分布的空间规律,为以后施肥决策提供依据,加速改善矿区土壤状况。[方法]以平朔矿区为研究区域,分别采集开采未损区、开采受损区、受损治理区3个区域的土壤样本各30组,再通过试验测得土壤的养分含量并用R和Sufer等进行分析处理获取不同区域的养分变化情况,最后根据样本各养分因子的隶属度值和权重系数对土壤养分情况进行了综合评价。[结果]通过和土壤养分含量分级与丰缺度标准相对比,结果表明平朔矿区的养分丰缺度为急缺或缺状态,除pH值外其他养分指标变异系数及含量波动大,尤其开采未损区。土地复垦虽然可以一定程度地改善矿区的受损土壤,但是受损治理区土壤要想恢复到开采前状态,还需要很长时间。[结论]平朔矿区的采矿和土地复垦对土壤养分含量和土壤养分分布有重要影响。     

修复后临汾湿地公园土壤养分状况及沉积物污染特征

为探究汾河临汾段湿地土壤及沉积物的理化性质、养分含量,评价土壤状况、预测水体的生态环境质量。共采集98个土壤及沉积物样本,分析了理化性质及养分等11项指标。结果表明:土壤pH在7.0~8.4,容重在1.04~1.44 g/cm^3,含水率在5.9%~17.5%,电导率在0.167~0.747 mS/cm,质地类型包括壤黏土和黏壤土;有机质、全氮、全磷含量分别为8.7~39.8,0.354~1.046,0.389~1.444 g/kg,碱解氮、速效磷、速效钾含量分别为12.9~50.3,2.6~31.2,86.4~329.2 mg/kg。经相关性分析可知,土壤各指标与物理性质相关性较强;沉积物各指标与质地显著相关,且有机质、全氮、碱解氮、速效钾两两相关;养分评价中,有机质、全磷、速效磷处于4级水平,全氮在3~6级均有分布,碱解氮分布在5,6级,速效钾分布在2,3级;沉积物在有机污染评价中表现中度污染,综合污染评价表现重度污染。     

漠河-大庆输油管道工程对沿线地区土壤养分的影响

为探讨漠河-大庆输油管道工程建设对沿线土壤养分的影响特征,在沿管线的19个代表性样段进行土样采集,对比分析作业带和非作业带的土壤养分状况.结果表明:管线建设对土壤肥力产生了显著影响,但其影响程度因肥力指标(土壤pH、有机质、全氮、全磷、全钾、速效氮、速效磷和速效钾)和土层(表层0-20 cm和底层20-40 cm)而异.管线建设显著提高了土壤pH值(P＜0.05),导致土壤出现偏碱化的趋势.作业带土壤有机质、全氮、速效氮和全磷含量显著低于非作业带(P＜0.05),说明施工导致其含量降低.作业带土壤表层全钾含量显著高于非作业带(P＜0.05),底层无显著差异,说明施工对土壤全钾含量造成一定的影响.作业带和非作业带表底层土壤速效磷和速效钾含量虽有差异但总体上不显著(P＞0.05),说明施工对其含量影响有限.这些结果说明管线建设过程中“分层开挖、分层堆放、分层回填”的重要性,也为指导管线建设和植被恢复提供数据基础和理论依据.     

重庆市涪陵区植烟土壤养分的适宜性评价及变异分析分的适宜性评价及变异分析

为明确土壤养分状况及变异特征，本研究以2012年和2017年涪陵区烟田土壤样品为研究对象，采模糊数学原理对土壤养分适宜性进行综合评价，运用t检验和多重比较方法分析了各肥力指标的变异情况。结果表明：研究区56.25%的土壤pH适宜，变幅在4.41～8.12之间；有机质含量变幅为7.62～39.99 g/kg，中等水平土壤占71.88%；全氮及速效氮、磷含量偏高，钾含量丰富。适宜性评价显示，2017年研究区植烟土壤适宜指数均值为0.6，变异系数为26.17%；适宜性指数分级表明，II级以上的植烟土壤占46.88%；与2012年相比，土壤pH、有机质、全氮、碱解氮、有效磷和速效钾分别增加了0.54、1.69 g/kg、0.58 g/kg、24.63 mg/kg、17.2 mg/kg和66.6 mg/kg。结果说明，研究区土壤酸化趋势有所减缓，氮、磷、钾及有机质等含量有逐渐增加趋势，因此，生产上要持续进行土壤改良，严格控制氮肥投入量，提升磷钾肥的有效性。     

不同土地利用方式对土壤养分及肥力的影响

以山东省临沂市四种典型土地利用方式为例,分析不同土地利用方式对土壤养分及肥力的影响.结果表明:不同土地利用方式对有机质(OM)含量具有显著影响,而对pH、全磷(TP)、全氮(TN)、全钾(TK)和土壤颗粒组成无显著影响.不同土地利用方式土壤OM含量由高到低顺序为:水田>未利用地>林地>旱地;TN含量由高到低顺序为:未利用地>林地>水田>旱地;TP含量由高到低顺序为:未利用地>旱地>林地>水田;TK含量由高到低顺序为:林地>水田>旱地>未利用地.相关分析表明,旱地各养分之间的相关系数要大于水田、林地和未利用地,不同土地利用方式对TP和TN之间的相关系数无影响.主成分分析表明,旱地、水田、林地和未利用地综合肥力指标F值大小顺序为:水田(0.86)>林地(0.78)>旱地(0.51)>未利用地(0.43).     

不同土地利用方式下土壤养分的分布及其与土壤颗粒组成关系

对四川紫色土区不同土地利用方式下土壤表层及剖面养分的分布特征及其与颗粒含量之间的关系进行了研究,结果表明:(1)林地、水田具有较高的土壤氮素和有机质(与旱地、果园、裸地均达到了显著差异),且林地剖面养分随土层深度的增加呈几何级数下降,但土壤磷素含量相对较低。(2)受施肥状况的影响,经济园林土壤磷素普遍偏高。(3)旱坡地的表层养分与底层养分含量差异不大,说明该区旱坡地土壤可能存在较大的养分流失与淋失现象,坡面径流、壤中径流携带的养分不容忽视。(4)土壤中大部分养分含量与土壤颗粒含量之间有一定的相关性,其中土壤全氮、碱解氮与粉粒(0.002～0.02mm)含量之间呈显著的正相关,与砂粒(0.02～2mm)含量之间呈极显著的负相关;土壤有机质与粉粒含量之间呈极显著的正相关,与砂粒含量之间呈极显著的负相关;而土壤全磷情况正好相反,与粉粒含量呈现极显著的负相关,与砂粒含量呈现极显著的正相关;只有碱解氮与粘粒(<0.002mm)含量之间的相关性达到了5%显著水平。     

阜平县不同海拔梯度下耕地土壤养分现状与分布特征

为在太行山区阜平县对耕地土壤提出科学合理的施肥理论依据,利用2018年阜平县耕地测土配方施肥调查数据,运用统计学和克里金插值方法研究了阜平县耕层土壤有机质、碱解氮、有效磷、速效钾及pH等养分含量现状及分布特征。结果表明:当前阜平县耕地土壤pH、有机质、碱解氮、有效磷和速效钾的均值含量分别为7.08,21.84 g/kg, 70.53 mg/kg, 22.43 mg/kg, 75.43 mg/kg,土壤pH值主要为中性水平,占比65.42%;土壤有机质含量、碱解氮含量和速效钾含量均表现为以中等含量水平为主,占比分别为45.55%,43.19%和59.86%,处于中等及以上的占比分别为98.76%,64.42%和75.96%;土壤有效磷含量主要处于高等含量水平,占比29.99%,而高等及以上水平占比74.15%。从空间分布上耕地土壤有机质、碱解氮、有效磷和速效钾大体均呈现由东南向西北逐渐增长的趋势,而从海拔梯度分区下有机质和有效磷呈现丘陵区(21.85 g/kg)<低山区(21.92 g/kg)<中山区(22.70 g/kg)趋势,碱解氮呈现中山区(64.72 mg/kg)&l...     

Assessment of ZN Interaction with Nutrient Cations in Alkaline Soil and its Effect on Plant Growth

An experiment was conducted to assess the zinc (Zn) availability to wheat in alkaline soils during Rabi 2009–2010. Wheat seedlings in pots having 2 kg alkaline sandy soil per pot were treated with 5, 10 and 15 kg Zn ha^?1 as soil and with 0.5 and 1.0% zinc sulfate (ZnSO₄) as foliar application. Results showed that Zn increasing levels in soil helped in phosphorus uptake up to boot stage but its conversion to grain portion lacked in Zn treated plants. Potassium (K) uptake also increased up to 6.24% in boot stage with treatment of 10 kg Zn ha^?1 + 1.0% ZnSO₄ foliar spray. Zinc (Zn) concentration increased in plant tissues with the increasing level of Zn application but this disturbed the phosphorus (P)-Zn interaction and, thus, both of the nutrients were found in lesser quantities in grains compared to the control. Despite of the apparent sufficient Zn level in soil (1.95 mg kg^?1), improvement in growth and yield parameters with Zn application indicate that the soil was Zn deplete in terms of plant available Zn. The above findings suggest that the figure Zn sufficiency in alkaline soil (1.0 mg kg^?1) should be revised in accordance to the nature and type of soils. Furthermore, foliar application of Zn up to 1.0% progressively increased yield but not significantly; and it was recommended that higher concentrations might be used to confirm foliar application of Zn as a successful strategy for increasing plant zinc levels.     

西藏土壤有机质和氮素状况及其影响因素分析

根据西藏16个土类168个土壤剖面的分析资料,探讨土壤有机质和氮素状况及其影响因素。西藏土壤有机质>30g/kg和20～30g/kg的面积分别占39%和46%;其地理分布既有广阔高原面上的水平地带性变化,也有山地和深切河谷的垂直地带性变化。土壤有机质中活性腐殖质一般占30%～45%,以酸性土中的比例较大。土壤全氮>1 5g/kg,1 0～1 5g/kg和<1 0g/kg的面积分别占40%,44%和16%;碱解氮>150mg/kg和<90mg/kg的面积分别占36%和61%。全氮与有机质呈线性正相关;碱解氮与全氮、有机质呈非线性正相关,并与活性腐殖质有密切关系,它在部分土壤中还受有机质C/N的制约。     

Nutrient Removal,Fertilization Needs and Yields of Protea Plants Cultivated in Subtropical Conditions

A study of nutrient removal was carried out in commercial protea plantations of each of the cultivars ‘Scarlett Ribbon,’ ‘High Gold,’ ‘Veldfire,’ and ‘Sunrise’ of Leucospermum cordifolium, and of the species L. patersonii,located in a subtropical region (La Palma, Canarian Archipelago).

Flowering stems of optimal commercial quality were taken from each of the mentioned cultivars and species, once a year (2003 and 2004) at harvest time (January to April), and the different organs were analyzed separately. Flowering stems of the cultivars ‘High Gold’ and ‘Veldfire’ presented the highest contents of most studied nutrients, whereas the opposite was observed in ‘Scarlett Ribbon’ and L. patersonii. Mean yields of flowering stems varied very much among cultivars, and the highest ones were those of ‘High Gold’ and ‘Scarlett Ribbon’. The cultivar ‘High Gold’ removed the highest quantities of studied nutrients, and the contrary was observed in L. patersonii for most of them.

Suitable rates of nitrogen (N): phosphorus (P): potassium (K) fertilizers for nutrient restitution purposes were 1:0.08:0.40 for ‘Scarlett Ribbon,’ 1:0.08:0.66 for ‘High Gold,’ 1:0.08:0.38 for ‘Veldfire,’ 1:0.09:0.75 for L. patersonii;and 1:0.18:1.11 for ‘Sunrise’.     

镜泊湖区4种主要森林类型的土壤养分状况和微生物特征

通过实地调查与试验分析,研究了镜泊湖区杨桦林、蒙古栎林、人工落叶松林和人工红松林的土壤养分状况和微生物特征。结果表明:杨桦林的土壤有机质含量、全氮含量、水解氮含量、全磷含量及速效磷含量均为最大,其土壤细菌数量、放线菌数量和微生物总量也最大;蒙古栎林的土壤有机质含量、全氮含量、水解氮含量、全磷含量、速效磷含量、细菌数量、放线菌数量、真菌数量和微生物总量均比杨桦林小,比人工落叶松林和人工红松林大;人工落叶松林和人工红松林,除真菌数量处于最高水平外,其土壤的养分状况、细菌数量、放线菌数量和微生物总量均为最小。杨桦林、蒙古栎林、人工落叶松林和人工红松林的有机质含量比例为633∶299∶294∶100,全氮含量比例为1013∶539∶331∶100,水解氮含量比例为868∶418∶310∶100,全磷含量比例为411∶279∶127∶100,速效磷含量比例为523∶220∶271∶100,微生物总量比例为180∶130∶103∶100。