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1.
通过对泉州市1999—2003年的5处耕地连续定位监测分析。结果表明:土壤基础地力随着种植时间的推移,在连续不施肥后逐年有所下降。与监测前相比,各监测点施肥区耕层土壤有机质、全氮含量仅有微小增加,碱解氮含量变化虽然有波动,但总体上略有下降,而有效磷增幅较大并呈盈余积累丰富状态,速效钾均有显著降低并呈低指标含量状态。表现出土壤养分平衡状况是氮磷有盈余而钾亏缺严重。肥料投入结构不平衡,有机肥料在施肥中的份额逐年下降,化肥投入量逐年增加,氮磷钾养分比例不协调。  相似文献   

2.
为促进区域茶园科学合理施肥,以当地茶园推荐的化肥施用量为对照(CK),设置了6个梯度有机肥施用量作为处理,即:3 000(FQ1),4 500(FQ2),6 000(FQ3),7 500(FQ4),9 000(FQ5),12 000 kg/hm~2(FQ6),分析了有机肥施用量对茶叶产量和品质、土壤养分及氮素利用的影响。结果表明:不同处理对茶叶产量及产量性状存在极显著影响(P0.01);与CK相比,养分投入量相当(或更少)条件下施用有机肥造成了茶园产量及产量性状不同程度地下降(降幅为4.32%~32.28%),进一步增加有机肥施用量才可获得较好的产量及产量性状。与CK相比,有机肥施用量≥4 500 kg/hm~2时提高了茶叶水浸出物含量,其中FQ6处理茶叶水浸出物含量得到显著提高(P0.05);施用有机肥对茶叶茶多酚和氨基酸含量的影响相对较小,仅2019年FQ5和FQ6处理显著提高了茶叶氨基酸含量及2020年FQ1处理显著降低了茶叶茶多酚含量(P0.05);有机肥施用量对茶叶咖啡碱及酚氨比不存在显著影响(P0.05),但一定程度提高了茶叶咖啡碱含量并降低了茶叶的酚氨比。与CK相比,不同有机肥施用量均可缓解茶园土壤酸化状况并显著提高茶园土壤碱解氮含量(P0.05);除FQ1处理,施用有机肥处理显著提高了茶园土壤有机质和速效钾含量(P0.05);FQ1显著降低了茶园土壤有效磷含量(P0.05),而FQ5(2019年)和FQ6处理显著提高了土壤有效磷含量(P0.05)。氮素盈余量和氮肥偏生产力随着氮肥施用量的增加分别表现出极显著增加和下降趋势(P0.01),其中:CK与养分投入量相当条件下施用有机肥(FQ3处理)的氮素盈余量和氮肥偏生产力差异不显著(P0.05);氮素盈余量、氮肥偏生产力与氮肥施用量的关系分别呈线性(y=0.786x-115.04,P0.01)和幂函数关系(y=635.28x~(-0.605),P0.01),即随着肥料氮投入的增加,氮素盈余量和氮肥偏生产力分别呈增加和下降趋势。基于2019,2020年的茶叶产量反应,应用线性加平台模型拟合每年有机肥最佳施用量为8 739.55~9 169.95 kg/hm~2,但造成氮素盈余量过大和氮肥偏生产力较低,并增加了环境污染的风险。综上,茶园施用有机肥虽然降低了产量,但提高了茶叶品质,改善了茶园土壤养分状况;同时,从氮素利用角度考虑,茶园施用有机肥时不应过分追求茶叶产量,可适当降低有机肥施用量以控制氮的投入。  相似文献   

3.
氮磷钾不同用量及配比对日光温室黄瓜产量和品质的影响   总被引:16,自引:3,他引:16  
在日光温室内,采用无土栽培方式研究了不同氮磷钾用量和配比对黄瓜产量及品质的影响,结果表明:增加氮素的用量和比例可以显著提高黄瓜产量、单株果实数和单果重,适量增氮可显著提高果实可溶性蛋白含量,但进一步加大用量和比例则使之降低,增氮显著降低Vc含量,增加果实的硝酸盐含量,可溶性糖含量有升高趋势,但差异不显著;增磷对黄瓜产量、单株果实数和单果重亦有明显促进作用,对果实可溶性蛋白没有明显影响,大量增磷可以降低果实可溶性糖含量,增磷可明显降低Vc含量,但显著提高果实硝酸盐含量;同时增加氮磷提高黄瓜产量,但果实硝酸盐含量较对照增加95%。增钾没有明显的增产效果,对单株果实数和单果重影响不大,可以增加黄瓜果实的可溶性蛋白含量,显著降低Vc和可溶性糖含量,但相对于增氮、增磷,增钾使Vc下降的幅度较小,显著降低果实硝酸盐含量,且用量和比例越大,效果越明显。  相似文献   

4.
中国农田土壤磷平衡现状及驱动因子分析   总被引:8,自引:1,他引:7  
结合GIS平台对1996及2002年我国县域农田土壤磷平衡状况分析结果表明,全国农田土壤磷平衡存在很大的时空变异。1996年及2002年县域农田土壤磷盈亏范围分别为-20~425 kg/ha及 -17~450kg/ha。农田土壤磷盈余量在20~50 kg/ha的县市占全国总县市的比例从1996年的34.2%下降到2002年的24.1%,而磷盈余量在50~100kg/ha的县市所占比例从29.3%增加到33.4%,农田土壤磷盈余量在6年间普遍提高了一个等级。区域尺度上,化肥磷投入是影响磷平衡空间分异的直接因素,而有机肥的影响不明显;种植业结构变化是影响磷平衡时空变化的间接因素;农业收入是经济欠发达地区影响磷肥投入的主要原因之一。  相似文献   

5.
长期小麦秸秆还田对壤质潮土磷素含量及磷盈亏的影响   总被引:1,自引:0,他引:1  
明确长期小麦秸秆还田壤质潮土土壤中磷素演变特征,可为潮土区土壤磷素管理和磷肥高效施用提供理论依据。利用壤质潮土长期定位试验(1992-2015年),比较单施化肥处理(NP、NPK)和小麦秸秆还田配施化肥处理(NPS、NPKS)土壤有效磷、全磷含量变化,量化土壤磷盈亏和累积磷盈亏,并解析土壤有效磷变化量与累积磷盈亏之间的关系。结果表明,长期施用磷肥和小麦秸秆还田显著提高了土壤有效磷和全磷含量,提升了磷活化系数(PAC),其年增量分别为0.68~0.78mg/kg、0.0031~0.0047g/kg和0.07%~0.09%,且小麦秸秆还田对土壤有效磷含量的增加速率有抑制作用,对全磷含量的增加有促进作用,但效应不显著。小麦秸秆还田增加土壤磷盈余。在土壤磷盈余时,土壤每盈余100kg/hm2磷,有效磷增加9.7~10.0mg/kg,小麦秸秆还田对其影响不大;在土壤磷亏缺时,土壤每亏缺100kg/hm2磷,秸秆不还田土壤有效磷含量降低12.6mg/kg,小麦秸秆还田土壤降低1.95mg/kg,小麦秸秆还田对土壤有效磷含量的维持有缓冲作用。小麦秸秆配施磷肥是提高和维持壤质潮土土壤磷素水平、增强土壤供磷潜力的重要措施。  相似文献   

6.
以紫花白品种为试验材料,采用组织培养方法,在离体条件下研究了NaCl和Na2SO4两种混合盐胁迫对马铃薯脱毒苗抗氧化系统及Na+、K+含量变化的影响。NaCl和Na2SO4分别按2:1(A),1:1(B)和1:2(C)摩尔比例混合,每一种比例下设7个盐浓度梯度,即0、0.15%、0.30%、0.45%、0.60%、0.75%和0.90%。主要结果如下:混合盐胁迫下,三种比例马铃薯脱毒苗SOD活性、POD活性变化趋势相似,均存在在某一盐浓度下活性突然增加的趋势,盐浓度对马铃薯脱毒苗叶片SOD活性、POD活性影响极显著,盐比例及盐浓度和盐比例交互作用对马铃薯脱毒苗叶片SOD活性、POD活性影响不显著;随混合盐浓度的增加Na+含量显著增加,K+含量平缓下降, Na+/K+比值则显著上升。  相似文献   

7.
长期施肥下褐土中不同磷组分对磷素盈余的响应   总被引:2,自引:0,他引:2  
研究褐土区长期不同施肥对土壤磷素形态和磷素累积的影响,对不同磷组分与磷素盈余之间进行相关性分析,为促进土壤中磷素向作物易于吸收的形态转化、提高磷素的利用效率提供依据,从而进一步探索合理的磷肥调控措施。选用其中的9个处理,即不施肥处理,4个不同水平氮、磷化肥配施处理,3个有机肥无机肥配施处理以及1个单施高量有机肥处理。供试土壤取自1992-2012年在山西省寿阳县宗艾镇北坪旱塬上长期定位试验的0~20 cm耕层土壤,运用Hedley磷素分级方法测定耕层土壤不同组分磷素含量,分析长期不同施肥处理对耕层土壤磷素形态及盈余的影响,计算不同形态磷素与磷素盈余之间的相关性。结果发现,有机肥无机肥配施及单施高量有机肥促进了土壤磷素向活性较强的磷素形态转化,使H_2O-P和NaHCO_3-P含量迅速增加;不同施肥处理对耕层土壤中H_2O-P、NaHCO_3-P含量影响较大;随着磷素投入量的增加满足植物的需求后,会有大量活性较强形态的磷素向Na OH-P转化;不同施肥处理对HCl-P含量的影响差异性较小,对于Residual-P含量有降低的趋势。各处理土壤磷素盈余量大小表现为:N_0P_0M_6N_3P_2M_3N_4P_4M_0N_3P_3M_0N_4P_2M_2N_2P_2M_0N_2P_1M_1N_1P_1M_0N_0P_0M_0。磷素盈余与各组分磷相关性表现为:HCl-PNaHCO_3-PResidual-PH_2O-PNaOH-P。长期单施高量有机肥或不合理有机肥无机肥配施会导致磷素在土壤中大量盈余,其中,单施高量有机肥的盈余量最大。当土壤中磷素投入量在33~61 kg/hm~2时基本可以满足植物的要求,N_4P_2M2_处理在满足植物需求的前提下当季利用率达到最大,为36.4%,推荐施磷量为61 kg/(hm~2·年)。土壤磷素盈余与稳定态磷素的相关性最大,磷素盈余会使磷素的利用效率迅速降低。合理的有机肥无机肥配施可以提高作物对磷素的利用效率。  相似文献   

8.
为了解三明市耕地土壤交换性镁含量空间分布特征及影响因素,利用三明市4833个土壤样品化验结果和相关数据,应用统计学和地理统计学方法对三明市耕地土壤交换性镁含量空间分布特征及其影响因素进行了分析。结果表明:三明市耕地土壤样品交换性镁平均含量处于中等水平,平均值为62.7 mg/kg。各县(市、区)土壤样品交换性镁含量差异达到显著水平。土壤交换性镁含量缺乏样品所占比例和缺乏的耕地面积所占比例分别达到44.15%和40.72%。除土壤类型分组的交换性镁含量差异不显著外,其他影响因素分组的土壤交换性镁含量差异均显著。因此施用有机肥、调节土壤pH、客土改良砂土类质地土壤、补充镁肥等可以作为调控三明市土壤交换性镁含量的主要措施。  相似文献   

9.
为探讨施磷处理(0、90、180、270、360、450 kg/hm2 P2O5)和植株不同结荚位置(上、中、下部)对紫花苜蓿(Medicago sativa)种子发芽特性的影响,测定了不同处理种子磷含量、单粒重、发芽率、发芽势等指标.结果表明:施磷处理为450 kg/hm2 P2O5时,种子磷含量最高;施磷处理为360 kg/hm2 P2O5时,种子单粒重最大;施磷处理对正常苗比例、硬实比例、发芽率、不正常苗比例、死种子比例以及发芽势的影响均不显著(p>0.05).苜蓿植株不同结荚位置的种子磷含量之间差异不显著(p>0.05),中、下部荚果内种子单粒重较上部重,并且下部荚果内种子的正常苗比例和发芽率均显著(p<0.05)高于中、上部荚果内种子,下部荚果内种子的不正常苗比例显著(p<0.05)低于中、上部荚果内种子.施磷处理和结荚位置之间的交互作用对各个指标的影响不显著(p>0.05).  相似文献   

10.
通过1992-2012年共20年的长期定位试验,探讨了施用钾肥和秸秆还田对河北省典型潮土区土壤钾肥力的影响,并对长期施肥和秸秆还田处理对土壤全钾含量、土壤速效钾和缓效钾以及农田钾素平衡对速效钾和缓效钾含量的影响等进行了分析。结果发现:连续20年不施用钾肥和秸秆还田,并未对河北省潮土的土壤全钾造成影响;秸秆还田(NPSt)、增施钾肥(NPK)和增施钾肥基础上秸秆还田(NPKSt)显著提高了土壤速效钾含量,提高幅度在44.2%~79.1%;而增施钾肥( NPK)和增施钾肥基础上秸秆还田( NPKSt )显著提高了土壤缓效钾含量,提高幅度在7.66%~37.3%。单施氮磷肥(NP)的土壤速效钾含量没有明显变化,但单施氮磷(NP)和秸秆还田(NPSt)的土壤缓效钾含量分别降低了20.8,9.8 mg/kg。增施钾肥基础上秸秆还田( NPKSt)的农田钾素平衡处于盈余状态,每盈余K2 O 100 kg /hm2,土壤速效钾和缓效钾分别增加2.71,24.4 mg/kg。试验结果表明,增施钾肥和秸秆还田对于提高农田土壤钾肥力具有重要促进作用。  相似文献   

11.
With the uninterrupted development of the socialist market economy, there are many phenomena such as mendacious accounting information and false account in the accounting practice. It is an inevitable request for us to amend and improve the Accounting Law, so as to make it reflecting the new content and playing a significant role in accounting work. In this paper, after a thorough discussion of the nature, background and characteristics of the newly revised Accounting Law, a great innovation of the law that laying the primary accounting obligation on the persons in charge of unit is pointed out and its rationality, function and duty are summarized and analyzed.  相似文献   

12.
为研究徐海鸡蛋品质性状间的内在关系,随机测定徐海鸡40周龄蛋品质,并运用典型相关分析对蛋内部品质性状和蛋壳品质性状的12个变量进行分析。结果表明:徐海鸡蛋重、蛋黄重和蛋白高度与大部分性状均呈显著或极显著相关,除蛋形指数外其余蛋壳品质性状也与大部分性状呈显著或极显著相关。典型相关分析结果表明徐海鸡蛋内部品质性状和蛋壳品质性状的第1个典型相关达到极显著水平(P<0.01),相关系数为0.8552,其相关信息占两组性状间总信息的79.67%,其中起主要作用的性状包括蛋白高度和蛋壳厚度。该研究结果对徐海鸡的选育利用具有指导意义。  相似文献   

13.
Summary Interactions of seven bio-morphological characteristics of sunflower (head diameter, number of flowers per head, number of seeds per head, 1,000-seed weight, volume weight, kernel content in seed, oil content) and their correlations with seed yield per plant were examined. The path-coefficient analysis provided information about direct and indirect effects of the examined characteristics on seed yield per plant. The correlation coefficients were positive and highly significant. The highest direct positive effect on seed yield per plant was exhibited by the weight of 1,000 seeds. Head diameter, volume weight and kernel content had a direct negative effect on seed yield per plant.  相似文献   

14.
ABSTRACT Linkages among changes in employment, earnings per worker, and pollution per square mile are estimated for 3,036 U.S. counties for the period 1987 to 1995 using a three‐equation disequilibrium adjustment model. Counties with higher shares of African‐Americans experienced higher earnings growth rates over the period 1987‐1995, as did counties with proportionally more females. Counties in states with higher shares of unionized workers had higher earnings growth rates but generated fewer new jobs. Firm size had a significant and negative effect on earnings growth while higher costs of living were associated with higher earnings growth. Also, metro counties and counties in the Northeastern U.S. experienced higher earnings growth than their non‐metro counterparts and counties in other geographic regions. Statistically, faster job growth was found to accelerate the rate of earnings growth per worker. The authors conclude that counties concerned with job growth should recruit or attempt to spawn the creation of larger firms, recognizing that for some firms such a strategy may come at the cost of more rapid increases in pollution. Counties concerned with increasing the rate of growth in per worker earnings should instead focus on the creation of smaller firms.  相似文献   

15.
Research was conducted to study interrelationships between agronomic and seed characters and their direct and indirect effects on seed yield per plant under normal and limited irrigation regimes. Two field experiments were conducted in 1996 at the Experimental Station of College of Agriculture, Shiraz University at Badjgah. Fourteen sunflower (Helianthus annuus L.) cultivars consisting of eight hybrids and six open pollinated varieties were grown in two randomized complete block designs with four replications. Two experiments differed in respect to irrigation regime. The cause and effect relationships of 12 different characters were assessed. Most of the characters including seed yield and oil content showed considerable genotypic and phenotypic variations. Water stress significantly decreased yield and its components, however, oil content did not differ significantly. Genotypic and phenotypic correlations revealed that seed yield had significant positive correlations with days to flowering, days to physiological maturity, head diameter, plant height, 1000-seed weight and oil yield under normal and limited irrigation. Seed yield had significant correlations with oil content and kernel percentage under normal irrigation regime, while these correlations were largely reduced under stress conditions and were not significant. The highest direct effect, was exhibited by 1000-seed weight and number of filled seeds per head in normal and limited irrigation environments. However, cause and effect relations of other traits with seed yield changed due to irrigation conditions. Direct effect of oil content was quite lower than its correlation with seed yield. The lowest direct effect was found for plant height and oil content under normal and stress environments, respectively.  相似文献   

16.
芝麻素和芝麻林素在芝麻种子萌发阶段变化规律的研究   总被引:1,自引:0,他引:1  
为了明确芝麻种子发芽过程中芝麻素、芝麻林素、水分和干物质量的变化规律,以2个芝麻种质KUUS709和YZH11为材料,研究芝麻种子在21℃发芽条件下芝麻素、芝麻林素、水分和干物质量的变化规律。结果表明,在芝麻种子发芽前期、中期和后期,芝麻素含量和芝麻林素含量呈现出“慢—快”的降解规律,芝麻素和芝麻林素含量变化的转折点在萌发36 h和48 h;水分含量和干物质量呈“S”型曲线,符合“慢—快—慢”的增长规律,其中水分变化的转折点是在萌发24 h和84 h,干物质积累量变化的转折点在萌发36 h和96 h。在芝麻种子发芽过程中,水分与干物质量呈显著正相关,芝麻素含量与芝麻林素含量呈显著正相关;水分、干物质量与芝麻素含量、芝麻林素含量呈显著负相关。本研究将为进一步探讨芝麻素和芝麻林素在种子发芽过程的生理机制奠定基础。  相似文献   

17.
选取三江平原主栽水稻品种龙粳29、龙粳31和龙粳46,应用人工气候箱在水稻抽穗期和灌浆期进行低温处理,[目的]通过对水稻外观品质、营养品质和RVA谱特征参数的分析,研究水稻发育中后期低温对品质影响。[结果]在抽穗期和灌浆后期经低温处理后对水稻外观品质的影响较大,各生育期蛋白质含量均显著上升,RVA谱特征一级参数均显著下降,直链淀粉和二级参数因品种差异有升有降。本次研究的性状中共有17对极显著相关和5对显著相关,最高粘度的相关性最大,与6个性状有相关性,垩白粒率与5个性状有相关性等,每个性状至少有两个或两个以上性状相关联。[结论]该试验根据低温对水稻品质影响进行判断,为三江平原水稻品质认证提供理论依据,同时也为水稻生产栽培和抗性育种提供理论依据。  相似文献   

18.
豫中烤烟烟碱和总氮含量与中性香气成分含量的关系   总被引:15,自引:0,他引:15  
在对浓香型烤烟产区27个上二棚烟叶样品分析测定的基础上,研究了烟碱和总氮含量与烟叶中性香气成分含量的关系。结果表明,烟叶烟碱和总氮含量与类胡萝卜素类香气成分含量呈显著的二次曲线相关关系,在烟碱含量为3.82%时总类胡萝卜素类香气物质含量最高,在烟碱含量1.28%~3.92%范围内巨豆三烯酮2、巨豆三烯酮4、法尼基丙酮、二氢猕猴桃内酯和香叶基丙酮含量随烟碱含量的增高呈持续增加趋势。西柏烷类降解产物茄酮含量与烟碱和总氮含量也呈极显著的二次曲线相关关系,但茄酮含量最大值分别出现在烟碱含量为2.62%,总氮含量为2.77%时,此后显著下降。糖和氨基酸棕色化反应产物仅个别成分与烟碱和总氮含量显著相关。芳香族氨基酸降解产物总量、新植二烯和中性挥发性物质总量与烟碱和总氮含量呈显著的二次曲线相关关系,在烟碱和总氮含量分别为2.89%和3.05%时中性挥发性物质总量出现最大值。  相似文献   

19.
Limited information is available on genetic variation in low-nitrogen (low-N) stress tolerance and N-use efficiency (NUE) among maize inbreds. To unveil this information, a panel of 189 diverse maize inbred lines was evaluated under contrasting levels of N availability over 2 years. Low-N agronomic efficiency (LNAE), absolute grain yield (GY) at low-N conditions, and the ratio between GY at low-N and optimum-N conditions were taken into account to represent low-N tolerance. Additionally, N-agronomic efficiency (NAE) along with other agronomic traits was also analyzed. Analysis of variance revealed significant effects of genotype on LNAE, NAE, and GY. The estimated broad-sense heritability was 0.38 for LNAE while it was only 0.11 for NAE, implying that selection based on LNAE should be more effective than NAE. LNAE exhibited highly positive genotypic and phenotypic correlations with GY, ear kernel number (EKN), kernel weight, plant height (PH), and chlorophyll content at low-N conditions, while it was negatively correlated with grain-N content and anthesis-silking interval. Path analysis indicated that the EKN at low-N stress had the highest positive effects on LNAE.  相似文献   

20.
以山西省中晚熟区大面积推广、生育期基本相同的20个玉米品种为试验材料,对穗部相关性状与收获期子粒含水率进行相关性分析和通径分析。相关性分析结果表明,收获期子粒含水率与穗粗、轴粗、粒厚、苞叶总面积、收获时苞叶含水率呈极显著正相关,与粒宽呈显著正相关,与行粒数呈极显著负相关。通径分析结果表明,对收获期子粒含水率直接作用大小排列为穗行数>穗粗>苞叶含水率=粒厚>轴粗>行粒数>粒宽>穗长>苞叶总面积。因此,要选育收获期子粒含水率低的玉米新品种,应着重选育苞叶总面积小、收获时苞叶含水率低、穗粗与轴粗、子粒厚度薄、子粒宽度窄、行粒数多的基因型。  相似文献   

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