A Preliminary Study on Dynamics and Models of N,P,K Absorption for High-Yield Cotton

The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over the whole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N in leaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton than in CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than in CK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be described with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5 and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2O5 and K2O was 385.8, 244. 7 and 340.3 kg ha-1, respectively. Approximately 12. 5 kg N, 8. 0 kg P2O5 and 11.1 kg K2O were needed for producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 in Xinjiang.

N P K施用量与芹菜硝酸盐积累和产量的相关性

采用三因素五水平通用旋转组合设计，对Ｎ、Ｐ、Ｋ施用量与芹菜硝酸盐积累和产量的相关性进行了研究，并建立了三元二次回归方程。结果表明：Ｎ肥的施用与芹菜体内硝酸盐积累呈正相关，Ｐ、Ｋ肥的施用与之呈负相关；Ｎ、Ｐ、Ｋ皆有利于芹菜产量的形成，作用大小的顺序为Ｎ＞Ｐ＞Ｋ；三元素在影响芹菜硝酸盐积累及产量上具有交互作用。无土栽培芹菜Ｎ、Ｐ、Ｋ最优组合方案为Ｎ：８９．６０～１１２．５５ｍｇ·ｋｇ－１；Ｐ：２０．８０～２４．９６ｍｇ·ｋｇ－１；Ｋ：１７１．６０～２１８．４０ｍｇ·ｋｇ－１。

Plant Biomass, Primary Production and Mineral Cycling of a Mixed Oak Forest in Linnebjer, Sweden

Plant biomass, primary production and mineral cycling were studied in a mixed deciduous forest (Quercus robur L., Tilia cordata L. and Corylus avellana L.) in southern Sweden. Plant biomass amount above and below ground was 201 and 37 t&middotha-1, respectively. Primary production above and below ground was an estimated 13.3 and 2.3 t&middotha-1, respectively. Carbon was the dominant element in the forest ecosystem, comprising 133 t&middotha-1. Other major elements were: N > Ca > K > Si > Mg > S > Mn > P > Fe and Na (range 1123 to 18 kg&middotha-1), followed by some trace elements. Yearly litterfall restored 6.0 t&middotha-1 organic matter or 2.3 t&middotha-1 carbon. Approximately 45% decomposed and returned to the soil during the year. Monitoring of other elements revealed that the ecosystem received inputs through dry and wet deposition, in particular 34.4 kg&middotha-1 S and 9.4 kg&middotha-1 of N yearly as throughfall. Determination of yearly biomass increase showed that the oak forest ecosystem was still in an aggradation or accumulation phase.

Macronutrients Uptake in Soybean as Affected by <i>Bradyrhizobium japonicum</i>Inoculation and Phosphorus (P) Supplements

Field and glasshouse experiments were conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on macronutrient uptake by soybean. The treatments consisted of B. japonicum inoculation (with & without), phosphorus supplementation at the levels of 0, 20, 40 and 80 kg P·ha-1. Both treatments were replicated four times in a split plot design. The macronutrients considered were N, P, K, Ca and Mg. Results showed that inoculation with B. japonicum significantly contribute to the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole soybean plant. Likewise, phosphorus supplementation significantly enhanced the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole plant. The use of effective strains of rhizobia and P supplementation was an effective way of enhancing the growth of soybean, eventually the uptake of macronutrients in plant organs.

N,P,and K characteristics of different age groups of temperate coniferous tree species in northwestern China

This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the different tree species,ages and components,we sampled leaves,branches,stems,and roots,and measured the contents of Nitrogen,Phosphorus,Potassium,along with soil fertility.The changes of N,P,and K contents in the different tree species were studied,and the relationship between nutrient content and environmental factors was analyzed.The results indicated that the content of P in all three species was the lowest(0.039–0.28 g kg),while N content was the highest(0.095–1.72 g kg).As the terminal organ of nutrient transport,the nutrient content of leaves was the highest.P.armandii(0.45 g kg) had a higher nutrient concentration than P.tabulaeformis(0.19 g kg) and P.crassifolia(0.29 g kg).The nutrient content of each species was highest in a young forest,but lowest in a mature forest.The nutrient content of all three tree species was significantly affected by soil nutrient content,and negatively correlated with available soil nutrients.

Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.)

一个水耕法的实验被执行决定在小白菜(Brassica chinensis L.) 在氮(N) ，磷(P) ，和钾(K) 的生长，硝酸盐累积，和集中上用 20 单个氨基酸在营养液代替 20% nitrate-N 的影响射击。20% nitrate-N 什么时候与完整的硝酸盐处理，新鲜的小白菜射击和干燥重量相比被精氨酸( Arg )代替，但是20% nitrate-N 什么时候被丙氨酸(翼)代替，显著地增加了( P ≤ 0.05 )，缬氨酸(瓦尔)，白氨酸(列伊)，异白氨酸( Ile )，脯氨酸(专业版)，本氨基丙酸( Phe )，蛋氨酸(相遇)，天门冬酸(毒蛇)， glutamic ( Glu )，离氨酸( Lys )，甘氨酸( Gly )，丝氨酸(重量的单位)，苏氨酸( Thr )，半胱氨酸( Cys )，和酷氨酸( Tyr )，新鲜的射击和干燥重量显著地减少了( P ≤ 0.05 )。在用天门冬素(Asn ) 和夫酸安(Gln ) 代替 20% nitrate-N 以后，新鲜的射击和干燥重量是未受影响的。比作完整的硝酸盐处理，氨基酸代替处理除了 Cys， Gly，组氨酸(他的) ，并且 Arg，显著地减少了(P ≤ 0.05 ) 在植物射击的硝酸盐集中。显著地除了 Cys，列伊，专业版，和在另外的氨基酸处理的植物组织的遇见的、全部的 N 集中增加了(P ≤ 0.05 ) 。氨基酸也影响了全部的 P 和 K 集中，但是效果不同取决于单个氨基酸。改进小白菜射击质量， Gln 和 Asn 由于他们小白菜生长上的不足道的效果，他们在硝酸盐集中的重要减小，和他们宏元素的增加在植物满足，可以被用来部分代替 nitrate-N。

The Growth Characteristics of Three Terrestrial Plants Cultivated with Biogas Slurry as a Hydroponic Medium

Biogas slurry is a traditional high-quality organic liquid fertilizer. Three terrestrial plants with high economic value, fu gui cai, yang xin cai and strawberry, were selected for hydroponic cultivation using an optimal dilution of biogas slurry. The results of the experiments showed that strawberries could bloom and bear fruit and fu gui cai and yang xin cai grew well. However, in comparison with the control groups planted in soil, all three crops were subject to a certain degree of environmental stress, as shown by changes in growth, biomass indicators, physiological indicators and morphological indicators. The leaves and stems of yang cai and fu gui cai were tested for several types of heavy metals, and all met the requirements for human consumption. It is feasible to cultivate these three plants with biogas slurry. The results of this study can help guide hydroponic production practices and have practical significance and reference value.

NaCl处理对海滨锦葵N、P和Na^+、K^+含量及其化学计量特征的影响

为更好的开发利用耐盐经济植物海滨锦葵(Kosteletzkya pentacarpos),以了解盐处理下其N、P及Na+、K+吸收,本研究以海滨锦葵幼苗为材料,研究了不同盐浓度(0、2、4、8、12、16 g·L-1Na Cl)处理对海滨锦葵N、P和Na+、K+离子含量及其化学计量特征的影响,处理50 d后采样分析。结果表明:海滨锦葵在高盐环境(16 g·L-1Na Cl)下,增强了对N的吸收,其中茎中N增加尤为明显。同时,茎、叶和全株的含P量也明显增加。相关分析表明,叶片P含量与盐梯度显著正相关(P<0.05)。茎、叶和全株的Na+含量随着盐梯度的增加而增加,尤其叶中Na+含量增加最为明显。叶中Na+含量与盐梯度呈极显著正相关(P<0.01)。茎、叶中K+含量随着盐梯度的增加表现明显下降趋势,其中叶中K+含量下降较为平缓,盐梯度与叶中K+含量表现显著负相关。盐梯度与植株N/P呈一定正相关,Na Cl盐梯度处理并没有对K+/Na+产生明显影响,植株保持相对较为稳定的K+、Na+离子平衡状态(即相对稳定的K+/Na+)。海滨锦葵叶中N与P显著正相关(P<0.05),与叶N/P极显著正相关(P<0.01),而与叶K+/Na+极显著负相关(P<0.01),说明对栽培海滨锦葵的滨海滩涂盐碱地施加氮肥,可以很好地促进植株对P的吸收。盐碱地一定量的Na Cl对海滨锦葵的生长无害,并有益于增强对P的吸收与积累。本研究结果对指导实践栽培具有重要的现实意义。

麦秸还田对水稻产量及地表径流NPK流失的影响

在大田试验条件下,以水稻品种运2645为供试材料,设置常规处理(A)、麦秸还田(B)、麦秸还田减肥(C)、肥料运筹(D)和旋耕(E)5个处理组合,研究不同处理对水稻产量及农田地表径流NPK流失的影响。结果表明:(1)麦秸还田使水稻产量比常规处理增加3.0%左右;(2)试验年度稻季农田总地表径流水量为4.3×103m3·hm-2;(3)麦秸还田减肥和麦秸还田处理比其处理明显降低农田地表径流水体NPK流失量,不同处理地表径流总N流失量由低到高依次为麦秸还田减肥、麦秸还田、常规处理、肥料运筹和旋耕,不同处理地表径流总P和K的流失量由低到高依次为麦秸还田减肥、麦秸还田、肥料运筹、常规处理和旋耕;(4)麦秸还田能够降低稻田地表径流NPK的流失率,但麦秸还田减肥处理由于流失量减小幅度远低于肥料施用量的减小幅度,其NPK流失率均表现为最高;(5)麦秸还田使水稻产量略有增加,使稻田地表径流水体NPK流失量和流失率均明显降低。

N、P、K肥对香根草修复土壤镉、锌污染效率的影响

通过盆栽试验研究在30 mg/kg镉(Cd)污染土壤条件下N[CO(NH2)2:100、200、300 mg/kg土]、P(P2O5:50、100、200 mg/kg土)和K(KCl:100、200、300 mg/kg土)处理对香根草修复土壤Cd和锌(Zn)污染效率的影响。结果表明:3种N处理能促进香根草地上部生长,而且显著提高地上部特别是叶的Cd和Zn含量,导致其修复效率成倍显著增加;200 mg/kg K处理显著提高Zn修复效率,但300 mg/kg K和50、200 mg/kg P处理却显著降低Cd、Zn修复效率。因此,为改善香根草对较贫瘠土壤中Cd、Zn污染的修复效率,应对香根草适施N肥,并控制或者不施P、K肥为佳。

硝态N累积与菠菜有机N形成及P、K吸收的关系

在低N(0.3g·kg-1土)和高N(0.6g·kg-1土)2个水平下,采用土壤盆栽试验,研究了30个菠菜品种硝态N累积情况及其与植株生长,有机N形成,P、K吸收的关系。结果表明:施N水平低时,30个菠菜品种的硝态N含量与生长量、有机N总量和P、K吸收量之间均无显著的相关关系;高N时,菠菜品种间硝态N含量表现出显著的差异,硝态N含量最高与最低相差242mg·kg-1,与生长量、有机N总量和P、K吸收量之间亦呈极显著正相关关系。

藻类爆发对太湖梅梁湾水体中NPK含量的影响

1998～ 2 0 0 0年对太湖梅梁湾的实测结果表明 ,在一定范围内叶绿素a的含量与温度呈现明显的正相关 ;NH4+ N和总氮 (TN)、总磷 (TP)含量在每年的八九月份最低 ,总含量与叶绿素a呈正相关 ,随着叶绿素a含量上升 ,N、P含量呈现下降趋势 ;K的含量与N、P相似 .排污口的 0号点和 6号点的N、P含量相对于湖中心的 8号样点来说极高 ,而且P已不是限制性营养元素 ,在其它水域 ,P依然是限制性营养元素 ,表明微囊藻 (Microcystisspp .)只在TN含量为 1～ 4mg·L-1、TP在 0 .1～ 0 .

N、P、K营养元素不同配比对马占相思苗期生长的影响

采用N、P、K 3营养元素 5个水平配比试验 ,分析不同配比对马占相思苗期生长的影响 ;通过正交试验 ,确定马占相思苗木对各营养元素的实际需求水平。结果表明 ,P素对马占相思苗期生长影响最大 ,其次为K素 ,而N素的影响相对较小。不同水平的N、P、K配比对试验苗有不同的影响 ,其中 ,N∶P∶K最佳配比为 :190∶2 5∶16 0 (mg·L- 1)。

专用缓释肥料对黄瓜产量品质及N,P,K养分吸收利用的影响

采用土培试验研究了黄瓜专用缓释肥对黄瓜产量品质及N,P,K养分吸收利用、土壤酶活性的影响.结果表明:2种专用缓释肥(CSRF1和CSRF2)显著提高了黄瓜果实干物质量和总干物质量,CSRF1和CSRF2处理黄瓜果实干物质量较CCF,MSRF,OCF处理分别增加了23.3%~37.2%和16.5%~31.6%.2种专用缓释肥(CSRF2和CSRF1)提高了黄瓜果实的维生素C质量分数和氨基酸的质量分数,降低了硝酸盐质量分数.黄瓜根、茎、叶和果实的N,P,K养分质量分数均以CSRF2最高.黄瓜N,P,K积累量从大到小依次为CSRF2、CSRF1、MSRF、CCF、OCF,专用缓释肥处理的N,P,K积累量较MSRF,CCF和OCF处理分别提高了27.45%~46.55%,33.17%~56.20%和67.61%~102.13%.与普通复合肥相比,2种专用缓释肥处理的N,P,K相对养分利用效率分别增加了18.53%~24.20%,19.27%~20.02%和18.54%~35.69%.

施硒对苦荞N,P,K营养元素和土壤有效养分含量的影响

采用盆栽试验研究土壤施硒对不同生长期苦荞N,P,K营养元素和土壤有效养分含量的影响。结果表明,除80 d的Se0.5处理外,施硒增加了苦荞茎的N含量,茎的P含量在60 d时除Se0.5处理外均显著降,40 d和80 d时均显著增加,施硒均降低苦荞全生育期茎的K含量。40 d时,叶的N,P含量降低,K含量在施硒≤1.5mg/kg范围升高0.46～0.8个百分点;60 d时,叶的N,P含量在低浓度硒时降低,高浓度硒时升高,K含量除Se0.5处理外均显著降低;80 d时叶的N,P含量除Se2.0处理外均降低,施硒各处理叶的K含量显著降低。花的N含量除Se0.5处理外均高于不施硒处理,P含量均不同程度降低,K含量显著提高。除Se0.5处理外,子粒的N,P,K均有所提高。施硒对速效氮的影响因硒水平和苦荞生育期各异,土壤有效磷、钾含量均随外源硒浓度的增加而增高。

关于p^k元域中的n方元素

设 F为 pk元域 ,n为正整数 .本文建议 F中的 n方元素的概念 ,给出 n方元素的特征性质 .最后 ,给出

不同生育时期根际土壤渍水逆境对冬小麦N、P、K素营养的影响

运用盆栽模拟土壤渍水逆境试验,研究不同生育时期根际土壤渍水逆境对不同小麦品种N、P、K素吸收、运转和分配的影响。结果表明,根际土壤渍水逆境对不同小麦品种N、P、K素吸收的影响有异;不同生育时期根际土壤渍水逆境显著影响根系对N、P素的吸收、运转与分配,以孕穗期渍水逆境影响最大,其次为灌浆期和拔节期,而不同生育时期根际土壤渍水逆境对K素的吸收影响较小。孕穗期以前渍水逆境主要影响小麦根系对N、P、K素的吸收,对N、P、K素在小麦体内的运输和分配影响较小;灌浆期渍水逆境不仅影响根系对N、P、K素的吸收,同时也影响N、P素在地上部各器官中的运转和分配,但对K素在小麦体内的运转和分配影响较小。因此,基肥中施足P肥和K肥,拔节孕穗期重施速效N肥,灌浆期叶面喷施KH2PO4对于培育壮秆大穗,减轻小麦渍害,提高受渍小麦籽粒产量具有非常重要的实际意义。

长江河口九段沙互花米草湿地生态系统N、P、K的循环特征

研究了九段沙外来入侵种互花米草(Spartina alterniflora)湿地生态系统的营养元素含量、分布规律与循环特征。结果表明,九段沙的上沙、中沙和下沙互花米草湿地土壤全量养分含量差异相对较小,而速效性养分含量差异相对较大。土壤剖面中TK含量大大高于TN和TP含量,排序为:TK>TN>TP。各沙洲速效性养分含量排序为:速效K>速效N>速效P。土壤速效性养分与全量养分的空间分布规律并不一致,土壤剖面营养元素的垂直分布差异比较明显,速效性养分土壤剖面垂直分异比全量养分显著。各深度土壤营养元素含量均存在差异,不同沙洲同一深度土壤营养元素含量也存在差异。各沙洲不同深度土壤TN含量的差异明显大于TP和TK含量差异。植物中3种营养元素含量以K最高,N其次,P最低。湿地生态系统营养元素归还量远大于存留量。吸收系数排序为:N>P>K。不同沙洲营养元素的利用系数和循环系数存在明显差异,上沙P元素、中沙与下沙K元素利用系数最大,上沙K元素、中沙P元素与下沙N元素循环系数最大。

莲雾遮光期叶片SPAD值和C、N、P、K含量的变化及其规律

对大田莲雾成年树进行遮光处理,研究遮光叶片SPAD值及C、N、P、K含量的动态变化及其规律。结果表明:叶片SPAD值受叶龄和遮光互作影响,自然条件下,叶龄40 d左右SPAD值最大,达到63.0±2.49。短时间遮光对叶片SPAD值的影响不大,遮光40 d叶片SPAD值降到最低;长时间遮光会造成叶片早衰,限制树体营养生长。遮光对叶片N、P、K、C含量均有影响,在遮光过程中,叶片的C、N、P、K含量的变化情况不尽相同,但树体对遮光后形成的弱光条件均作出响应,然后通过自身的调节,慢慢使C、N、P、K趋同于自然条件下的含量水平。莲雾叶片的碳氮比(C/N)随着遮光时间的延长而呈增大趋势,遮光40 d左右比值达到顶峰,此时是莲雾栽培上进行催花的一个关键时间点。

常绿阔叶林藤本植物叶片N、P、K生态化学计量学特征

【目的】研究广西大明山国家级自然保护区常绿阔叶林中30种藤本植物叶片N、P、K生态化学计量学特征,为丰富群落生态化学计量学提供基础数据。【方法】在大明山天坪站保存完好的常绿阔叶林中设置20m×20m标准样地80块,共3.2ha,在每个标准样地左下角设置5m×5m的小样方,对藤本植物多样性进行调查,根据重要值,采集30种藤本植物叶片,进行叶片N、P、K含量测定。【结果】叶片N、P、K变化范围分别为3.52～54.71、0.21～3.36、0.48～4.23g/kg。各个化学计量因子之间存在一定的线性关系,草质藤本叶片N∶K含量均大于木质藤本,P含量差异不显著。【结论】大明山常绿阔叶林中多数藤本植物是受N或P或N∶P的影响,约30%的种类受到N元素限制,而受到P元素限制的植物相对少;草质藤本叶片比木质藤本有更强的N、K元素存储能力。