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1.
塔里木盆地冲积新成土土壤质地对土壤性状的影响   总被引:2,自引:0,他引:2  
季方  樊自立  赵虎 《土壤》1999,31(3):126-131
通过塔克拉玛干沙漠腹地两个大剖面土壤质地的变化,分析了冲积新成土土壤质地对土壤性状的影响。分析结果表明,受土壤颗粒吸收的影响,细土层土壤有机质和全盐含量高于砂土层。在大量的微量元素中,细土层Fe2O3,Al2O3,P2O5,CaO,MgO,MnO,TiO2,V,Cr,Ni,Cu,Zn,Sr,Y,Nb,Tb和Pb的含量高于砂土层,而SiO2,Na2O和Ba5的含量低于细土层。  相似文献   

2.
【目的】为了准确测定出一年生作物旱地土壤的养分含量,精准施肥管理,减少农业面源污染。【方法】本研究通过肥效试验,比较作物两种土壤采样方式(窝间和行间)不同施肥方式及不同高度作物的碱解氮、有效磷、速效钾、有机质、pH值。【结果】作物窝间和行间土壤取样法对土壤养分检测结果影响很大。不同施肥方式和高度作物的土壤碱解氮、有效磷和速效钾都是窝间比行间取样法高;不同施肥方式方面,干施+水施的碱解氮、有效磷、pH与干施的碱解氮、速效钾和水施的pH,其窝间与行间差异都达显著以上;不同高度作物方面,矮秆作物的碱解氮、速效钾和高秆作物的pH,其窝间与行间差异都达显著。【结论】旱地如蔬菜等一年一熟或一年多熟窝(穴)植密植作物,在作物成熟后翻耕前取土样,其窝间与行间取样检测结果有差距,建议旱地一年生作物土壤取样方法以采集作物窝间和行间中间位置相同点数和数量的土样。  相似文献   

3.
黄河三角洲冲积平原湿地土壤酶活性与养分相关性研究   总被引:1,自引:0,他引:1  
对黄河三角洲冲积平原湿地酶活性与土壤养分相关性做了研究。结果表明,随着离海距离的增加,土壤有机质及各养分表现出有规律的变化,土壤脲酶、过氧化氢酶活性沿湿地演替的方向活性升高,过氧化物酶活性降低。土壤有机质和各养分与酶活性相关性达极显著和显著水平,不同土壤酶活性之间也有显著的相关性。三种酶可以作为评价黄河三角洲冲积平原湿地土壤肥力的指标。  相似文献   

4.
桂北柑橘园土壤化学性状研究   总被引:5,自引:1,他引:5  
为了解桂北柑橘园土壤化学状况,2017年在桂北7个柑橘主产县(市)选取102个代表性柑橘园采集土壤样本,对pH、有机质和10种养分进行定量分析。结果表明:土壤pH变幅3.95~8.02。其中,pH处于强酸性(pH<4.5)、酸性(pH 4.5~5.5)和碱性(pH>7.3)范围的果园分别占总样本数的24.51%、48.04%和9.80%,大部分果园土壤pH为强酸性和酸性,有64.70%的果园土壤pH适宜或基本适宜(pH 4.5~7.0)柑橘生长,但仅有14.71%的果园土壤pH适宜柑橘生长(pH 5.5~6.5)。土壤有机质含量丰富,适量及以上水平的比例达86.27%。果园土壤营养元素丰缺并存,失衡比较明显,其中,有效磷和有效钾含量不足(低量或缺乏)的比例分别为33.33%和30.39%,超标(高量或过量)比例分别为21.57%和23.53%;碱解氮和有效钙含量主要在适量范围,不足比例分别为36.27%和31.37%;有效铁和有效锰含量丰富,超标比例分别为64.71%和55.89%;有效镁、锌、铜和硼含量不足比例较高,分别为59.80%、92.16%、56.86%和50.9...  相似文献   

5.
我国旱地两熟区土壤养分时空变异的调查研究   总被引:4,自引:0,他引:4  
旱地两熟区是我国旱作农业重要区域,同时也是主要的粮食产区。本研究基于文献资料查阅、地方测土配方施肥数据收集等方式,分析旱地两熟区农田土壤养分盈缺状况。结果表明:以全国土壤养分含量分级标准为参照,我国旱地两熟区农田土壤养分含量总体达到中等水平,区域间养分含量差异较大,以云南高原最好,江淮丘陵次之,华北平原、黄土高原和川中丘陵最差;与其他粮食主产区土壤肥力相比处于中下等水平;与80年代全国第二次土壤普查数据相比,绝大部分旱地两熟区的农田土壤养分含量明显增加,但对于原始地力较高的云南高原地区,土壤有机质和速效钾含量稍降。在今后的田间管理中合理施肥、秸秆还田和保护性耕作等精细农田管理措施将成为提高该区土壤肥力的关键。  相似文献   

6.
蒙西灌区春小麦高产田耕层土壤理化性状调查   总被引:1,自引:0,他引:1  
本文报告了蒙西灌区春小麦高产田(7500kg/hm^2)土壤耕层理化性状的调查。结果表明:高产田的理化性状明显优于该区的其它耕作土壤。其主要特点是:耕层厚(20-30cm),属于上虚(容重1.20-1.26g/cm^3),下实(容重1.35-1.43g/cm^3)的土体构型。土壤质地为砂质壤土-壤土。松紧适中,孔隙状况适宜(总孔隙度52.4%-54.85),耕性良好,有机质平均含量为1.70%,全N、全P、全K含量分别为0.124%、0.198%、2.04%。碱解N、速率P2O5、速率K2O的含量分别为87.1、1.10、119.4mg/kg。土壤微量元素,铁含量丰富、铜硼适量、锌锰缺乏。  相似文献   

7.
潮土区不同质地土壤的养分动态变化研究   总被引:17,自引:6,他引:17  
对华北平原大兴县 1 982— 2 0 0 0年两个时段大量土壤样本的分析结果表明 ,土壤养分含量与土壤质地表现出明显的一致性 ,体现了土壤质地越重 ,养分含量越高的特点 ;土壤质地对土壤养分含量的影响 ,1 982年的大于 2 0 0 0年的 ;但 2 0年来 ,由于土地利用集约度的增强 ,质地对土壤养分水平的影响渐趋减弱 ,不同质地土壤的养分水平渐趋一致  相似文献   

8.
浙江省丘陵旱地土壤供钾能力的研究   总被引:4,自引:0,他引:4  
浙江省主要丘陵旱地土壤的全钾量随母岩中长石和云母的含量增加而增加,幅度为0.57—3.13%,速效钾和缓效钾的含量分别为33—216ppm和80—638ppm,与土壤中高岭石及伊利石的相对含量有关。以化学试剂连续提取、电超滤(EUF)和强度/数量关系研究结果表明:高岭石为主的土壤,其缓冲容量(PBCk)较低,有效钾数量较少,且缓效钾释放慢,在黑麦草耗竭试验中,经1—2次收获后,产量和吸钾量明显下降。以伊利石为主的土壤,其缓冲容量(PBCk)高,黑麦草试验可得到连续的高产和吸取较多的钾。黑麦草试验还表明土壤的供钾特性较之其有效钾储量更有实践意义。  相似文献   

9.
闽东南旱地土壤养分状况与花生平衡施肥研究   总被引:8,自引:0,他引:8  
28个土壤样品的养分测定和吸附试验以及8个田间肥效试验表明,闽东南旱地土壤的N,P,K,B是花生的普遍养分限制因子,部分土壤还缺乏Zn和Mg等养分。赤砂土的肥料三要素最佳用量N54kg/hm^2,P2O555kg/hm^2,K2O87kg/hm^2;红壤性水稻土为N52kg/hm^2,P2O563kg/hm^2,K2O92kg/hm^2;海砂土为N94kg/hm^2,P2O542kg/hm^2,K  相似文献   

10.
旱地聚土免耕土壤微生物特性研究   总被引:1,自引:0,他引:1  
以中国科学院四川盐亭生态实难丫聚土免耕定位试验点土壤为材料,研究了其策生物区系、数量及2特点,结果表明,聚土免耕耕作法0~50cm土层微生物总数、主要生理类群的数量较常规耕作法增加:15~35cm土层微生物数量最高,聚土免耕土壤微生物分布规律为:中层(15~35cm)〉表层(0~15cm)〉底层(35~50cm)。  相似文献   

11.
Soil microbes are an essential component of most terrestrial ecosystems; as decomposers they are responsible for regulating nutrient dynamics, and they also serve as a highly labile nutrient pool. Here, we evaluated seasonal variations in microbial biomass carbon (MBC) and nitrogen (MBN) as well as microbial activity (as qCO2) for 16 months with respect to several factors relating to soil moisture and nutrients under different land management practices (plant residue application, fertilizer application) in both clayey (38% clay) and sandy (4% clay) croplands in Tanzania. We observed that MBC and MBN tended to decrease during the rainy season whereas they tended to increase and remain at high levels during the dry season in all treatment plots at both of our test sites, although soil moisture did not correlate with MBC or MBN. qCO2 correlated with soil moisture in all treatment plots at both sites, and hence soil microbes act as decomposers mainly during the rainy season. Although the effect of seasonal variation of soil moisture on the dynamics of MBC, MBN, and qCO2 was certainly greater than that attributable to plant residue application, fertilizer application, or soil texture, plant residue application early in the rainy season clearly increased MBC and MBN in both clayey and sandy soils. This suggests that plant residue application can help to not only counter the N loss caused by leaching but also synchronize crop N uptake and N release from soil microbes by utilizing these microbes as an ephemeral nutrient pool during the early crop growth period. We also found substantially large seasonal variations in MBC and MBN, continuously high qCO2, and rapid turnover of soil microbes in sandy soil compared to clayey soil. Taken together, our results indicate that soil microbes, acting as both a nutrient pool and decomposers, have a more substantial impact on tropical sandy soil than on clayey soil.  相似文献   

12.
为明确大理白族自治州(简称大理州)植烟土壤理化特征与烟叶化学成分的关系,采集并分析了大理州12个植烟县(市)的土壤和烟叶样品.结果 表明:①大理州植烟土壤质地为重壤土,pH值和速效钾适宜,有机质、碱解氮、有效磷、水溶性氯和有效硼偏高,其中大理市速效钾偏低,漾濞水溶性氯偏高.②大理州烟叶总糖和糖碱比偏高,其他指标适宜.其...  相似文献   

13.
赣北红壤坡地土壤流失方程关键因子的确定   总被引:5,自引:2,他引:5  
土壤流失方程是开展水土流失监测,指导水土流失防治的重要技术工具。针对红壤坡地土壤流失方程因子算法和取值研究薄弱的问题,基于野外径流小区观测资料,采用80%经验频率法确定了赣北红壤区侵蚀性降雨标准为降雨量10.0 mm、平均雨强1.3 mm/h、最大30 min雨强5.0 mm/h,区内次降雨侵蚀力采用总动能和最大30 min雨强乘积计算最佳。通过建立基于年降雨量的逐年侵蚀力简易算式,测算土壤可蚀性因子以及6种生物措施因子、5种工程措施因子取值,选定适宜的地形因子算式,构建了赣北红壤坡地土壤流失方程体系。经检验,模型能良好预报赣北红壤坡地多年平均土壤侵蚀强度;年际尺度预报的精度整体较高,但对于降雨较多年平均水平浮动较大或地表出现沟蚀等侵蚀类型时,预报精度将有所降低。有关因子的确定可为土壤流失方程在南方红壤坡地水土流失监测和水土保持规划中的应用提供技术支撑。  相似文献   

14.
为了明确有机物料替代部分化肥长期定位施用对冬小麦连作农田土壤养分的调控效应。在陇东黄土旱塬进行连续11年的定位试验,比较不施肥(CK)、施用等量氮磷养分的3种有机物料(生物有机肥、秸秆还田、农家肥)与氮磷化肥配施的农田土壤养分含量变化。结果显示:2016年冬小麦收获后,相比于CK,施用有机肥明显增加了0~60 cm土层硝态氮积累量,而有机质、全量氮磷钾及其速效养分含量在0~60 cm土层范围内随土层深度增加逐渐降低,且0~20 cm土层为硝态氮、有机质、全量氮磷钾及速效氮、磷富集区。从0~20 cm土层平均养分含量来看,施用有机肥显著提高了土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾含量。其中生物有机肥处理11年土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾含量分别较CK提高了18.39%、11.49%、15.62%、2.76%、14.94%、143.25%、36.33%,农家肥处理分别提高了14.42%、14.94%、14.06%、2.84%、10.87%、100.7%、41.58%,秸秆还田分别提高了7.20%、10.34%、9.38%、1.46%、9.24%、54.66%、8.82%。因此,在陇东半湿润偏旱雨养农业区,采用化肥与有机肥配施,兼顾钾肥的施肥措施是最合理的施肥方式,有利于保持黑垆土养分平衡,促进农田生产力稳定可持续。  相似文献   

15.
The effects of charcoal production on soil textural and chemical properties were investigated in Ejura, Ghana. The aim was to study the effects of heating and charcoal residue on maize yield, soil texture and soil chemical properties. Composite samples were taken from the 0–10 cm layer of soil at charcoal-making sites and from adjacent fields (control). Twelve sites were randomly selected for the study across the range of the Kotokosu watershed. Maize was planted in four selected locations on charcoal site soils (CSS) and adjacent field soils (AFS) to assess the impact of charcoal production on crop yield. There was a significant increase in soil pH, base saturation, electrical conductivity, exchangeable Ca, Mg, K, Na and available P in the soil at the kiln sites as compared to the adjacent soils. A relative change of up to 329% was observed in K while organic C and total N decreased by 9.8% and 12.8%, respectively. Organic C and total N were highly correlated ( P <0.01) and both parameters significantly ( P <0.05) depended on clay minerals in the soils. Soil texture was also modified with a significantly higher sand content and lower clay fraction in the CSS. The grain and biomass yield of maize increased by 91% and 44%, respectively, on CSS as compared to AFS. Further research to ascertain the long-term effects of charcoal production on the soil environment and the fertility of tropical soils is needed.  相似文献   

16.
土壤不同形态钾含量与土壤颗粒的关系   总被引:4,自引:2,他引:4  
赵斌  李静  马丽  郑耀 《土壤》2002,34(3):164-169
土壤含K矿物同其他矿物颗粒一起均分布在不同粒级的土粒中,这些土粒在不同的土壤中构成了不同的配合比例,形成不同的土壤质地的属性。统计表明,<0.05mm与<0.01mm粒级间呈极显著线性相关(r=0.896**,n=92),相关分析表明,不同粒级的土粒与不同形态K间呈显著线性或曲线显著相关,而全K只与<0.05mm粒径的土粒呈极显著相关(r=0.234**,n=73),全K与速效K的数量关系通过全K、<0.05mm、<0.01mm粒级与速效K系统相关组合的算式以数学的方法计算速效K含量。  相似文献   

17.
In spring 1995 a silty clay soil was compacted dynamically by wheeling with graded wheel loads up to 6 times. The reaction towards wheeling was recorded immediately. In the following 3 years some soil physical parameters as well as the Enchytraeidae abundances were recorded regularly. To the first wheeling, the soil reacted plastically in vertical direction. The reaction became elastically after the 4th wheeling. After the 6th passage with a 5‒tonnes wheel load soil structure collapsed totally, which can be concluded from the stress ratios. After the wheeling event, abundances of Enchytraeidae decreased obviously compared to uncompacted plots. The increase in air permeability, air capacity, and the decrease of soil bulk density depend on primary tillage events. The recovery of Enchytraeidae abundances developed in parallel. Abundances seem to be regenerated in the 3rd year after the wheeling event. Primary tillage can help to induce biological and macroscopic structural regeneration of the top soil after a compaction event.  相似文献   

18.
针对旱改水稻田土壤酸化和土地贫瘠的问题,探究土壤改良剂和有机肥对旱改水砖红壤稻田的改良效果,以期为南方砖红壤地区旱改水农田土壤改良提供科学依据和技术指导。通过大田试验,采用正交试验设计,设置土壤改良剂种类(石灰、硅钙钾镁和草木灰)和用量、有机肥种类(秸秆、羊粪和混合发酵有机肥)和用量的处理,测定各处理土壤 pH值、有机质含量、微生物数量以及土壤氮、磷、钾养分含量。结果表明,水稻种植 15 d后,施用硅钙钾镁能显著提高土壤 pH值,但提升幅度较小。施用秸秆、羊粪和混合发酵有机肥均能显著提升土壤 pH值、有机质含量、微生物总量和土壤氮、磷、钾含量。当有机肥施用总量超过 90 t/hm2时,田间水稻倒伏率随有机肥施用量的增加而显著上升。因此,施用有机肥是旱改水稻田土壤改良的有效措施,但土壤改良和地力提升需循序渐进,不宜一次性过量施用有机肥,最佳施用量为 90 t/hm2。  相似文献   

19.
Data transformations between soil texture schemes   总被引:1,自引:0,他引:1  
Various soil texture schemes are in current use. These differ in the size ranges of their particle fractions. There is a need to establish simple methods to correlate these conventional schemes. Therefore I have defined closed-form exponential and power law functions to fit models to cumulative particle-size distribution data. I have tested the functions for their suitability (i) to represent cumulative particle-size distribution curves and (ii) to transfer data between distributions that differ in the size ranges of the particle fractions. I found that closed-form exponential functions adequately represent the cumulative particle-size distributions of fine-textured soils (clay, silty clay, silty clay loam, clay loam, silt loam and loam texture), whilst closed-form power functions better describe the cumulative particle-size distributions of coarse-textured soils (sand, loamy sand, sandy loam, sandy clay and sandy clay loam texture). The functions defined are found to be suitable to transfer data between different texture schemes. The use of this approach is illustrated by examples of data transformations between three widely used soil texture schemes: ISSS, Katschinski's and USDA.  相似文献   

20.
云南保山市植烟土壤养分状况与烤烟化学成分相关分析   总被引:2,自引:0,他引:2  
采用描述统计和典型相关分析方法研究了保山烤烟化学成分与土壤养分状况之间的关系,结果表明:①保山土壤养分含量总体处于富足状态,但土壤养分不均匀,微量元素硼和氯含量较低,烟叶的总糖和还原糖含量较高,烟碱和总氮含量适中,钾、氯含量偏低;②在一定范围内土壤中碱解氮和有效硼含量与烟碱、总氮含量存在显著或极显著正相关,有效磷和有效镁含量与烟叶还原糖、钾氯比、糖碱比和氮碱比呈显著或极显著正相关;③控施氮肥,增施磷肥,提高烟株对土壤中钾的利用率,适当增施微肥,有利于提高保山烟叶的质量。  相似文献   

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