Concentrations of foliar and surface soil in nutrients Pinus spp. plantations in relation to species and stand age in Zhanggutai sandy land, northeast China

The concentrations of the foliar and surface soil nutrients and the variation with species and stand age were studied inPinus spp. plantations in Zhanggutai area, northeast China. The results showed that the total N, total P and C: N ratio of the soil inP. sylvestris var.mongolica stands were significantly higher in comparison with those inP. tabulaeformis andP. densiflora stands. ForP. sylvestris var.mongolica, the foliar P concentration appeared to decrease with age, and the foliar N and K concentrations did not show a consistent change with age. As for the different tree species of the similar age, the foliar N and P concentrations were significantly different (p<0.05), being withP. sylvestris var.mongolica>P. densiflora>P. tabulaeformis. The foliar N: P ratio ofP. densiflora significantly was higher thanP. sylvestris var.mongolica andP. tabulaeformis, while the foliar K was no obvious difference between the three tree species. There were significant correlation (p<0.05) between soil total N and P, soil organic matter and total P, foliar N and P, but it did not show significant correlations between soil and foliar nutrient concentrations, which might attribute to the excessive litter raking, overgrazing and low soil moisture in this area. Based on the foliar N: P ratio, we introduced a combination threshold index of N: P ratio with their absolute foliar nutrient concentrations to determine the possible limiting nutrient. According to the critical N: P ratio and their absolute foliar N, P concentrations, theP. sylvestris var.mongolica stands showed a decreased N limitation degree with age, theP. densiflora stands showed unlimited by N and P in the whole, and theP. tabulaeformis stands showed co-limited by N and P. No significant difference in soil nutrient concentrations of the surface soils was found between 45, 29, 20-yr-oldPinus sylvestris var.mongolica plantation stands. Keywords coniferous trees - foliar nutrient concentration - limiting nutrients - N - P ratio - Zhanggutai sandy land CLC number S718.55 Document code A Article ID 1007-662X(2004)01-0011-08 Foundation item: This research was supported by Key Knowledge Innovation Project (KZCX3-SW-418) of Chinese Academy of Sciences.Biography: CHEN Guang-sheng (1978-), male, master candidate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. ChinaResponsible editor: Song Funan

Impact of fertilization on chestnut growth, N and P concentrations in runoff water on degraded slope land in South China

Growing fruit trees on the slopes of rolling hills in South China was causing serious environmental problems because of heavy application of chemical fertilizers and soil erosion. Suitable sources of fertilizers and proper rates of applications were of key importance to both crop yields and environmental protection. In this article, the impact of four fertilizers, i.e., inorganic compound fertilizer, organic compound fertilizer, pig manure compost, and peanut cake （peanut oil pressing residue）, on chestnut （Castanea mollissima Blume） growth on a slope in South China, and on the total N and total P concentrations in runoff waters have been investigated during two years of study, with an orthogonal experimental design. Results show that the organic compound fertilizer and peanut cake promote the heights of young chestnut trees compared to the control. In addition, peanut cake increases single-fruit weights and organic compound fertilizer raises single-seed weights. All the fertilizers increased the concentrations of total N and total P in runoff waters, except for organic compound fertilizer, in the first year experiment. The observed mean concentrations of total N varied from 1.6 mg/L to 3.2 mg/L and P from 0.12 mg/L to 0.22 mg/L, which were increased with the amount of fertilizer applications, with no pattern of direct proportion. On the basis of these experiment results, organic compound fertilizer at 2 kg/tree and peanut cake at 1 kg/tree are recommended to maximize chestnut growth and minimize water pollution.

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

A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen （N）, phosphorus （P）, and potassium （K） in pak-choi （Brassica chinensis L.） shoots. When 20% of nitrate-N was replaced with arginine （Arg） compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly （P ≤ 0.05）, but when 20% of nitrate-N was replaced with alanine （Ala）, valine （Val）, leucine （Leu）, isoleucine （Ile）, proline （Pro）, phenylalanine （Phe）, methionine （Met）, aspartic acid （Asp）, glutamic acid （Glu）, lysine （Lys）, glycine （Gly）, serine （Ser）, threonine （Thr）, cysteine （Cys）, and tyrosine （Tyr）, shoot fresh and dry weights decreased significantly （P ≤ 0.05）. After replacing 20% of nitrate-N with asparagine （Asn） and glutamine （Gin）, shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine （His）, and Arg, significantly reduced （P ≤0.05） nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased （P ≤ 0.05）. Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N.

Effect of nitrogen and phosphorus addition on leaf nutrient concentrations and nutrient resorption efficiency of two dominant alpine grass species

Nitrogen(N)and phosphorus(P)are two essential nutrients that determine plant growth and many nutrient cycling processes.Increasing N and P deposition is an important driver of ecosystem changes.However,in contrast to numerous studies about the impacts of nutrient addition on forests and temperate grasslands,how plant foliar stoichiometry and nutrient resorption respond to N and P addition in alpine grasslands is poorly understood.Therefore,we conducted an N and P addition experiment(involving control,N addition,P addition,and N+P addition)in an alpine grassland on Kunlun Mountains(Xinjiang Uygur Autonomous Region,China)in 2016 and 2017 to investigate the changes in leaf nutrient concentrations(i.e.,leaf N,Leaf P,and leaf N:P ratio)and nutrient resorption efficiency of Seriphidium rhodanthum and Stipa capillata,which are dominant species in this grassland.Results showed that N addition has significant effects on soil inorganic N(NO_(3)^(-)-N and NH_(4)^(+)-N)and leaf N of both species in the study periods.Compared with green leaves,leaf nutrient concentrations and nutrient resorption efficiency in senesced leaves of S.rhodanthum was more sensitive to N addition,whereas N addition influenced leaf N and leaf N:P ratio in green and senesced leaves of S.capillata.N addition did not influence N resorption efficiency of the two species.P addition and N+P addition significantly improved leaf P and had a negative effect on P resorption efficiency of the two species in the study period.These influences on plants can be explained by increasing P availability.The present results illustrated that the two species are more sensitive to P addition than N addition,which implies that P is the major limiting factor in the studied alpine grassland ecosystem.In addition,an interactive effect of N+P addition was only discernable with respect to soil availability,but did not affect plants.Therefore,exploring how nutrient characteristics and resorption response to N and P addition in the alpine grassland is important to understand nutrient use strategy of plants in terrestrial ecosystems.

菠萝N.P.K的诊断施肥综合法初步标准

根据早先发表的1185个菠萝叶片养分组成和产量的观察数据,本文提出了菠萝“诊断施肥综合法(DRTS)”标准.所用数据分为高产亚群体(大于60吨/公顷,含650个样本)和低产亚群体(小于60吨/公顷,含535个样本),并通过标准的诊断施肥综合法技术得出诊断标准.检验这些标准的可行性是用品外一些独立发表的N.P.K因子试验数据,这些数据包括了其产量的效应.在大多数资料里,这些新的诊断施肥综合法标准可实现临界值方法无法实现的正确N.PK营养诊断.因而,诊断施肥结合法可揭示,在通常被认为在足够范围内的营养缺乏问题.诊断施肥综合法还能增加评价养分平衡的精确性.而这种评价用临界值方法却被忽视了.

生草栽培对火龙果园土壤生境和枝条病害的影响

为探讨生草栽培对火龙果园土壤环境及枝条病害的影响,设置“京都1号”火龙果园土壤黑色防草布覆盖、生草和生草刈割覆草,以清耕做为对照等4个处理,采集并分析不同覆盖方式的火龙果园表层土壤温度、含水量以及氮、磷、钾含量变化,同时调查火龙果枝条冷害与病害发生情况。结果表明,生草,尤其是生草刈割覆草能够有效降低夏季高温时的表层土温,并提升冬季低温时的土温,从而调节夏冬季间土温变化,但对土温的影响随着土层深度增加而减弱。防草布则显著提高表层土壤含水量,明显延长夏季超过38℃不利于火龙果生长的时间段;生草刈割覆草和防草布均能提升表层土壤含水量,而在冬季生草栽培表现良好,但在夏季效果欠佳;相较于防草布覆盖,生草和对照(清耕)对土壤肥力有一定消耗,但生草刈割覆草却能提高土壤氮磷钾含量。因此,在喀斯特山地区火龙果园开展生草栽培,并将刈割植物残体覆盖于植株树盘上,可有效调节表层土壤小气候环境,改善火龙果生态条件,并减少枝条冷害与病害发生。

甘蔗脱毒原种苗田间繁育过程中氮、磷、钾营养元素的吸收及累积特征

探讨甘蔗脱毒原种苗不同生长时期氮、磷、钾营养元素的累积需求状况,为甘蔗脱毒原种苗田间繁育栽培过程中养分管理提供参考。试验分别在2020、2021年进行,调查中糖1号甘蔗脱毒原种苗全生育期生长情况,测定其生物量及其在各生育阶段根、茎、叶中氮、磷、钾各营养元素的含量,并分析氮、磷、钾的累积量、阶段吸收量、日吸收速率。结果表明:甘蔗脱毒原种苗从种苗假植到种茎最佳收获时需6~7个月可达15茎节,在7、8月至9月下旬(茎1期至茎2期)蔗茎生长速度最快,以茎4期(10月下旬至11月下旬)干物质量累积增加最快,此阶段为生物量累积的关键阶段。在甘蔗脱毒原种苗全生育期中各元素含量及累积量从高到低依次为钾>氮>磷,在根茎叶各器官中蔗叶、蔗茎始终为氮、磷、钾含量相对较高的器官,氮、磷、钾累积量在茎伸长生长1期前主要贮存于蔗叶中,而后以蔗茎为新的主要贮存器官。甘蔗对氮、磷、钾的吸收比例在苗期和分蘖期分别为24.84%、26.18%、27.74%,在茎1~3期(7月下旬至10月下旬)分别为55.54%、58.61%、52.30%,茎4、5期(10月下旬至12月下旬)分别为19.62%、15.20%、19.96%。因此,可根据各元素的阶段吸收量进行合理施肥,进而提高甘蔗脱毒健康种苗的品质和经济效益。试验明确了甘蔗脱毒原种苗生长过程中对氮、磷、钾的需求状况,可为今后甘蔗脱毒健康种苗田间规模化繁育生产的科学合理施肥提供依据,提高脱毒原种苗田间繁育效率和养分资源利用效率。

配比施肥对槟榔幼苗肥料利用率及养分协同效应的影响

为了明确N、P、K肥对槟榔幼苗生长及营养吸收与利用的影响,从而确定合理的槟榔幼苗施肥技术。以槟榔幼苗为对象,采用“3414”肥料配比田间盆栽试验,测定不同施肥处理对槟榔幼苗营养吸收与分布及肥料利用率的影响。结果表明:(1)施肥提高了槟榔幼苗的生物量和肥料利用率;在氮磷钾平衡施肥时,氮肥和磷肥相对利用率达到最大;在不施磷肥,氮钾平衡施肥时,钾肥相对利用率达到最大;(2)槟榔幼苗地上部氮养分积累量是影响其生物量的主要因子,地下部磷养分积累量是影响其生物量的主要因子;(3)相关性分析与通径分析表明,氮与磷可协同促进槟榔幼苗生物量的增长,但会受到施钾量及钾肥相对利用率的制衡,3种元素协同促进植株生物量增长。因此氮肥和磷肥的相对利用率是槟榔幼苗施肥的关键指标。综上,氮磷钾配比施肥有利于槟榔幼苗的营养吸收和利用,以N∶P∶K=2∶2∶2(T6)配比施用效果较好。

适宜氮磷钾用量和配比协同促进盆栽牡丹营养和生殖生长

【目的】牡丹是我国著名的木本观赏植物,施肥不平衡严重影响盆栽牡丹的生长和观赏效果。研究开花前后氮、磷、钾不同施用量和配施比例对盆栽牡丹生长的影响,确定适宜的氮、磷、钾施用量及配比,为盆栽牡丹精准施肥提供理论依据。【方法】本研究以5年生牡丹‘紫二乔’为供试材料,采用“3414”不完全正交回归设计进行盆栽试验,结合隶属函数法评价牡丹的生长状况,利用肥料效应模型拟合牡丹植株的综合隶属函数值与施肥量之间的数学关系,得出牡丹最佳生长的氮、磷、钾肥推荐施肥量。【结果】牡丹开花前后施用氮磷钾肥显著影响植株株高、茎粗、冠幅、花径和单株花数(P<0.05),适宜氮磷钾用量和配比促进盆栽牡丹营养和生殖生长的协同提高。氮、磷、钾三因素配合处理的牡丹综合隶属函数值均大于缺素处理,缺素处理又大于无肥处理,N_(2)P_(2)K_(2)处理的综合隶属函数值(0.73)是N_(0)P_(0)K_(0)的3.17倍。氮磷钾对牡丹综合生长的影响表现为氮>磷>钾。氮、磷、钾肥对牡丹营养和生殖生长存在明显交互作用,任一肥料水平的过量或不足均会抑制牡丹植株生长,降低观赏效果。采用一元二次、二元二次、三元二次肥料效应函数方程拟合牡丹的综合隶属函数值和施肥量,二者相关性均达显著水平,综合各肥料效应函数方程的推荐用量及相应的综合隶属函数值,得出牡丹开花前后氮(N)、磷(P_(2)O_(5))、钾(K_(2)O)的最优推荐施肥量分别为4.21、2.07、2.52 g/株,适宜的氮、磷、钾施肥比例为1∶0.49∶0.60。【结论】开花前后施用适量的氮、磷、钾肥可提高牡丹的农艺性状,促进牡丹的营养和生殖生长协同提高。氮、磷、钾的最优推荐施肥量为4.21、2.07、2.52 g/株,适宜的氮、磷、钾施肥比例为1∶0.49∶0.60。

抚育间伐对小黑杨人工林非结构性碳和氮磷钾生态化学计量特征的影响

了解不同林龄阶段小黑杨人工林各器官的非结构性碳(NSC)含量和氮(N)磷(P)钾(K)生态化学计量特征及其对抚育间伐的响应,从而为小黑杨人工林的科学经营提供依据。以黑龙江省大庆市红旗林场幼龄和中龄小黑杨人工林为研究对象,建立间伐强度为25%(以株数计)的抚育间伐样地,调查分析抚育间伐对小黑杨人工林各器官NSC含量和NPK生态化学计量的影响特征。研究结果表明,2种林龄小黑杨人工林具有各自不同的NSC含量和NPK生态化学计量分布特征。中龄林树叶、树枝和树根NSC含量较幼龄林分别降低31.76%、21.19%、38.98%(P<0.05)。中龄林树叶N含量较幼龄林增加11.85%(P<0.05)。中龄林树枝、树干和树根P含量分别较幼龄林分别降低17.57%、35.85%、60.11%(P<0.05),树叶、树枝、树干和树根K含量分别较幼龄林分别降低21.05%、34.67%、22.99%、46.22%(P<0.05)。抚育间伐显著影响小黑杨幼龄林树干和树根的NSC含量、中龄林树枝和树根的NSC含量(P<0.05)。抚育后幼龄林树干NSC含量增加29.35%,树根NSC含量降低40.37%;中龄林树枝和树根NSC含量分别增加12.81%、33.51%。抚育间伐显著影响小黑杨幼龄林各器官N含量、树枝K含量、树干P含量和中龄林树叶、树根K含量(P<0.05)。抚育后小黑杨幼龄林树叶、树枝、树干和树根N含量分别增加5.77%、15.68%、53.71%、10.85%,树枝K含量增加36.90%,树干P含量降低19.63%;小黑杨中龄林树叶和树根K含量分别增加20.86%、31.69%。树叶NSC含量与N含量极显著负相关(P<0.01),与K含量间显著正相关(P<0.05);树枝NSC含量与N含量显著负相关,与P含量显著正相关(P<0.05),与K含量极显著正相关(P<0.01);树干NSC含量与N含量极显著正相关(P<0.01);树根NSC含量与N含量极显著负相关,与P含量极显著正相关(P<0.01)。结果表明,林分未进行抚育时,小黑杨幼龄林和中龄林NSC和N、P、K元素在各器官中的分配格局差异明显;幼龄林碳资源更多地分配给根系,促使其生长延伸,中龄林更多地投入到树木地上部分生长与竞争。抚育间伐会改变小黑杨NSC和N、P、K在各器官中的分布格局,抚育后,2种林龄小黑杨地上部分与地下部分碳资源比例均发生改变。对小黑杨中龄林进行抚育间伐增加林木碳汇的同时也改善了P限制的状况。

不同岩茶产区土壤碳氮磷钾生态化学计量比及其对真菌多样性的影响

本文以福建武夷山正岩茶、半岩茶和洲茶产区为研究对象,系统分析并阐明不同岩茶产区土壤碳(C)、氮(N)、磷(P)、钾(K)含量及其生态化学计量比对真菌群落组成和功能的影响。结果表明:(1)不同岩茶产区土壤C、N含量差异不显著,半岩茶产区P含量显著高于正岩茶及洲茶产区(P<0.05),正岩茶产区K含量最高,3个产区之间K含量均呈现显著差异(P<0.05);(2)在正岩茶、半岩茶和洲茶产区,子囊菌门(Ascomycota)、担子菌门(Basidiomycota)和被孢霉菌门(Mortierellomycota)分别是主要真菌门类,毛壳菌属(Chaetomium)是正岩茶产区真菌优势属,沙蜥属(Saitozyma)是半岩茶和洲茶产区的真菌优势属;(3)FUNGuild功能预测结果表明,在正岩茶产区中,动物病原–内生–附生–真菌寄生–植物病原–木质腐生真菌相对丰度最高;在半岩茶产区中,内生–凋落物腐生–土壤腐生–未定义腐生真菌丰度最高,而未定义腐生真菌在洲茶产区丰度最高;(4)Mantel检验结果显示,岩茶产区土壤真菌群落主要受C∶K、N∶K和P∶K的影响。K与毛壳菌属、镰刀菌属(Fusarium)和曲霉菌属(Aspergillus),C∶K、N∶K、P∶K与沙蜥属呈极显著正相关(P<0.01);N与青霉菌属(Penicillium),P与沙蜥属呈显著正相关(P<0.05);C与镰刀菌属,K与沙蜥属,C∶N与毛壳菌属、青霉菌属和木霉属(Trichoderma)呈极显著负相关(P<0.01);N与镰刀菌属,K与被孢霉属(Mortierella),C∶K、N∶K与毛壳菌属、镰刀菌属和曲霉菌属呈显著负相关(P<0.05)。总之,不同岩茶产区土壤真菌群落主要受C、N、P、K计量比影响,而养分含量对真菌群落影响不显著。本研究对评估茶园土壤健康,提升茶园土壤生态系统功能具有重要意义。

GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N)

In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals.

不同施肥处理对金瑞油桃产量和品质的影响

为解决山西油桃园施肥不合理的现象,筛选出适合当地油桃生产的施肥配比和施肥量,以4年生金瑞油桃为试验材料,磷肥固定,氮肥和钾肥各设置4个梯度,以不施肥为对照,研究不同施肥处理对运城地区金瑞油桃产量和品质的影响。结果表明,适量增施氮肥和钾肥均可显著增加油桃的横纵径和单果质量,提高油桃可溶性固形物、可溶性总糖和维生素C含量,降低总酸度,提高果实糖酸比,改善果实品质和口感;但施氮量超过240 kg/hm^(2)时,过量的氮肥会降低油桃可溶性固形物、维生素C和可溶性糖含量,不利于油桃品质和产量的提升。与不施肥对照相比,处理N_(2)PK_(2)(N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)和K_(2)O 240 kg/hm^(2))和处理N_(2)PK_(3)(N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)、K_(2)O 360 kg/hm^(2))增产率分别为28.77%和31.34%,增产值分别为25 440元/hm^(2)和27 720元/hm^(2),经济效益显著高于其他处理。通过构建施肥模型,试验地金瑞油桃的钾肥最佳施用量为398 kg/hm^(2)。综上,不同施肥配比和施肥量对油桃内在品质和产量有较大影响,试验地油桃适宜的氮、磷、钾施用比例为1.0∶0.5∶1.0~1.5,推荐施肥量分别为N 240 kg/hm^(2)、P_(2)O_(5)120 kg/hm^(2)、K_(2)O 240~360 kg/hm^(2)。

10μm 1280×1024 HgCdTe中波红外焦平面阵列探测性能提升

对像元尺寸为10μm的1280×1024碲镉汞(HgCdTe)中波红外焦平面阵列的制备技术和性能进行了研究。通过B+注入制备小尺寸n-on-p平面结;采用高平整度HgCdTe外延材料和高精度的倒焊互连技术,实现高的电学连通率;采用多段温度填胶固化和边缘刻蚀工艺减轻HgCdTe器件和读出集成电路(ROICs)之间的热失配,从而降低焦平面器件失效率。在85 K焦平面工作温度下,研制探测器的光谱响应范围为3.67μm至4.88μm,有效像元率高达99.95%,并且探测器组件像元的平均噪声等效温差(NETD)和暗电流密度的平均值分别小于16 mK和2.1×10^(-8)A/cm^(2)。与像元尺寸为15μm的探测器相比,10μm的1280×1024中波红外探测器可获取更加精细的图像,具有更远的识别距离。目前,该技术已成功转移到浙江珏芯微电子有限公司(ZJM)的HgCdTe红外探测器产线。

缓释肥对白枪杆幼苗生物量和养分积累的影响

为探究4种缓释肥用量对白枪杆(Fraxinus malacophylla)幼苗氮磷钾(N、P、K)化学计量比与生物量的影响,筛选适宜苗木生长最优施肥量。以1年生白枪杆幼苗为研究对象,设置4种施肥量(0、1、2、4 kg·m^(-3)),不施肥(CK)为对照,对各器官生物量、生长量及N、P、K含量进行测定,并计算N、P、K积累量;对生物量及N、P、K进行曲线拟合,分析各器官N、P、K积累量及化学计量比与生物量之间的关系。结果表明:白枪杆幼苗养分积累及生物量均在缓释肥用量为1 kg·m^(-3)下效果最佳,且显著高于对照组(P<0.05)。各器官生物量及N、P、K积累量均表现为叶>根>茎,各器官及单株养分积累量均表现为N>K>P。各器官及单株N、P、K积累量与白枪杆幼苗生物量呈极显著正相关关系(P<0.01),N∶P、K∶P与生物量呈负相关,而N∶K与生物量呈显著正相关(P<0.05)。白枪杆幼苗各器官N∶P值均小于14,植物生长受N元素限制,N∶K<2.10、K∶P>3.40,植物生长不受K影响。综上所述:缓释肥用量为1 kg·m^(-3)时,有利于白枪杆幼苗的生长及各器官养分含量的积累。

甘肃中部干旱地区油用亚麻氮磷钾土壤养分丰缺指标研究

通过连续5年在甘肃中部干旱地区开展油用亚麻氮磷钾土壤养分丰缺指标田间试验研究得出:当地油用亚麻相对产量<50%(极低)、[50%~60%)(低)、[60%~70%)(较低)、[70%~80%)(中)、[80%~90%)(较高)、≥90%(高)6个肥力等级下相对应的土壤氮、磷、钾养分丰缺指标为全氮<0.38、[0.38~0.53)、[0.53~0.75)、[0.75~1.05)、[1.05~1.48)、≥1.48 g·kg^(-1);有效磷(P)<4.6、[4.6~7.8)、[7.8~13.1)、[13.1~22.1)、[22.1~37.3)、≥37.3 mg·kg^(-1);速效钾(K)<91.0、[91.0~117.3)、[117.3~151.1)、[151.1~194.7)、[194.7~250.9)、≥250.9 mg·kg^(-1);并提出了各肥力等级对应的推荐施N量分别为>130、(115~130]、(105~115]、(95~105]、(75~95]、≤75 kg·hm^(-2);施P2O5量分别为>110、(95~110]、(80~95]、(65~80]、(50~65]、≤50 kg·hm^(-2);施K_(2)O量分别为>70、(60~70]、(50~60]、(40~50]、(35~40]、≤35 kg·hm^(-2)。长期土壤养分监测表明,自1983年至今,当地油用亚麻产区土壤碱解氮、有效磷含量均呈上升趋势,全氮含量略有下降,速效钾含量则下降明显。从试验所得丰缺指标亦看出,目前当地土壤氮、磷素养分含量仍处于较低水平,而钾素养分含量虽仍处于较高水平,但与以往相比却呈明显下降趋势,表明当地油用亚麻生产中既要重施氮肥,增施磷肥,还要适当补施钾肥。

半夏测土配方施肥产量效应和氮磷钾吸收特性分析

目的:探索肥效对贵州半夏产量及养分吸收特性的影响。方法:采用“3414”测土配方施肥考察半夏产量及不同时期块茎对氮磷钾吸收特性,SPSS 22.0进行肥效方程拟合及不同时期块茎氮磷钾吸收的显著性分析。结果:氮、磷、钾肥施用量的变化对半夏产量具有显著相关性,通过对氮、磷、钾肥施用量与半夏产量的关系拟合得到单因素肥效方程、三因素肥效模型以及不同时期块茎吸收氮磷钾与产量的相关性模型,该区域半夏最佳施肥策略为氮肥74.19 kg/hm^(2)、磷肥87.28 kg/hm^(2)、钾肥25.48 kg/hm^(2);不同时期块茎对氮的吸收受磷肥施用的影响,当磷肥施用处于较高水平时,块茎对氮的吸收也处于较高水平;块茎对磷的吸收受钾肥施用的影响,当钾肥施用处于较低水平时,对磷的吸收处于较高水平;块茎对钾的吸收则受氮、磷施用的共同影响,高钾的施用有利于块茎对钾的吸收。结论:半夏不同生长期应采取不同的施肥策略以达到更高的产量,本研究对贵州半夏高产栽培有一定指导意义。

凉山州白术氮磷钾配比水溶施肥试验初探

为摸清凉山州白术种植施用N、P、K有效方式,促进提高产量,团队通过在凉山州二半山区土壤肥力高、中、低三个地块上进行白术N、P、K施用试验,结果显示,在土壤肥力高的区域,配比水溶施肥对产量影响大,但与配比不水溶施肥对产量影响差别不大,与等比例施肥效果更显著;土壤肥力中等的区域,配比水溶施肥与配比施肥的产量相差不大,配比水溶施肥比等比例水溶施肥的产量较高;土壤肥力低的区域,配比水溶施肥与直接配比施肥的产量近似,但与等比例施肥的产量高。因此,按照白术所需N、P、K的量,将不同的肥料所含元素比例进行精准测算后进行配比水溶施肥,可以提高白术亩产量。

结球甘蓝东洋206利用氮磷钾锰铁铜养分特点分析

试验旨在进一步优化结球甘蓝东洋206施肥方案,通过分析结球甘蓝对N、P、K、Mn、Fe和Cu等6种养分和中微量元素累积情况,确定合理肥料施用量和配比关系。结果表明,结球甘蓝东洋206干物质中全氮、全磷、全钾含量平均值分别为0.305、0.033 4、0.305 g·kg^(-1)。目标产量为117 201 kg·hm^(-2),N、P_(2)O_(5)、K_(2)O施用量达到273.99、68.27、304.16 kg·hm^(-2),锰、铁、铜施用量分别为161.34、697.63、22.09 g·hm^(-2)时就可基本满足养分平衡。结球甘蓝各处理N、P_(2)O_(5)、K_(2)O吸收量平均值为:215.04、54.07、258.09 kg·hm^(-2),N、P_(2)O_(5)、K_(2)O吸收量比例平均值为20.16∶5.00∶24.30。结球甘蓝Mn、Fe和Cu吸收量平均值分别为134.42、426.31、16.05 g·hm^(-2)。NPK肥料农学效率分别为101.36、97.86、16.03 kg·kg^(-1)。NPK肥料利用率分别为43.80%、15.85%和36.25%。

不同氮磷钾镁配比对砀山酥梨生长和养分吸收的影响

文章旨在探讨不同氮磷钾镁配比对砀山县酥梨的生长及营养物质吸收的影响。试验结果表明:在氮磷钾镁含量相同的条件下,不同配比对酥梨株高、枝数、叶面积、花芽形成率、果实发育情况及果实品质都有显著影响;不同配比对植株根系长度、干重、总糖含量、酸度、果汁含水量、果粒质量有明显差异;不同配比对土壤中有机质、矿质元素含量也有明显变化。其中,氮磷钾镁为1:2:1的比例下,酥梨株高最高,产量最大;氮磷钾镁为2:3:1的比例下,酥梨株高最低,但产量也较大;氮磷钾镁比例为1:4:0的比例下,酥梨株高最小,但果实品质最好。因此,建议在砀山县栽培酥梨时,应根据当地气候条件、肥料供应状况等综合因素来合理选择氮磷钾镁配比,以提高酥梨的经济效益。