植物法生物修复PAHs和矿物油污染土壤的调控研究

选择苜蓿草为供试植物,以污染物含量水平、专性细菌和真菌及有机肥为调控因子,进行了植物法生物修复多环芳烃(PAHs)和矿物油污染土壤的调控研究。结果表明,PAHs和矿物油的降解率与有机肥含量呈正相关,增加有机肥5%,可提高矿物油降解率17.6%～25.6%,PAHs降解率9%.在植物存在条件下,土壤微生物降解功能增强。多环芳烃总量的平均降解率比无植物对照土壤提高2.0%～4.7%.投加特性降解真菌可不同程度地提高土壤PAHs总量和矿物油的降解率。真菌对萤蒽、芘和苯(a)蒽/(艹屈)的降解有明显促进作用。而细菌能明显提高苊稀/芴、蒽和苯(a)萤蒽/苯(k)萤蒽的降解率。     

糙皮侧耳和鞘脂菌NS7对多环芳烃污染土壤的生物强化与协同作用

[背景] 真菌和细菌被认为在多环芳烃污染土壤生物修复过程中发挥协同作用,目前在真实土壤体系中开展真菌-细菌协同降解研究较少。[目的] 研究真菌和细菌对不同种类多环芳烃降解的差异及对蒽和苯并[a]蒽的生物强化与协同作用。[方法] 选用多环芳烃降解真菌和细菌各一株,在液体纯培养体系下分析它们对不同种类多环芳烃降解的差异,在土壤体系中采用放射性同位素示踪技术研究2种微生物对蒽和苯并[a]蒽的生物强化与协同作用。[结果] 供试细菌鞘脂菌NS7能够很好地降解低环种类多环芳烃,以蒽作为唯一碳源时可以将其完全降解,在复合污染条件下对菲、蒽、荧蒽、芘等降解效果突出（>90%）,对苯并[a]芘降解效果较差（9.76%）。相比而言,供试真菌糙皮侧耳菌对苯并[a]芘具有更好的降解效果（21.18%）,对低环多环芳烃降解效果明显不如降解菌NS7。在自然土壤中,蒽和苯并[a]蒽具有明显不同的矿化效率,分别为18.61%和4.28%,在蒽污染土壤中加入鞘脂菌NS7并未显著提高蒽的矿化率（P>0.05）,相比而言,苯并[a]蒽污染土壤中加入糙皮侧耳显著提高了污染物矿化效率（2.24倍）,表明真菌和细菌在土壤环境中的定殖存活能力可能影响了生物强化效果。采用灭菌土壤排除土著微生物的竞争排斥作用,研究了真菌菌丝对生物强化降解的影响,发现在蒽污染土壤中,真菌菌丝的迁移作用显著提高了细菌鞘脂菌NS7对污染物的矿化率,从1.75%提高到5.91%;而在苯并[a]蒽灭菌污染土壤中,接种糙皮侧耳却没有发现苯并[a]蒽矿化率提高的现象,表明自然土壤中真菌强化降解苯并[a]蒽的作用可能是源于真菌菌丝促进污染物和土著降解菌的接触,而非直接来自真菌本身。[结论] 细菌能够很好地降解低环种类多环芳烃,而真菌对高环种类多环芳烃降解效果较好。真菌可能通过菌丝促进土著微生物在土壤中的迁移,增大多环芳烃和土著降解菌的接触,从而促进了多环芳烃降解。研究加深了对多环芳烃污染土壤生物强化修复的认识,对发展基于真菌-细菌协同作用的生物强化与调控技术提供理论指导。     

花椒叶浸提液对土壤微生物数量和土壤酶活性的影响

通过用花椒叶浸提液浇灌盆栽花椒幼苗,研究浸提液对土壤酶和土壤微生物的影响.结果表明, 花椒叶浸提液使根际土中细菌、真菌和放线菌数量以及微生物总数均有不同程度的减少,根际土中真菌和放线菌的数量变化呈降-升-降-升的趋势.20、60和80 g·L^-1浓度的叶浸提液使非根际土中细菌的数量显著增加21.59%、107.55%和8.62%,而40 g·L-1浓度的叶浸提液则使非根际土中细菌数量显著降低22.56%.叶浸提液使根际土蛋白酶、蔗糖酶和酸性磷酸酶活性明显低于非根际土相应的酶活性,而过氧化氢酶和多酚氧化酶活性则显著升高.土壤的蛋白酶活性与蔗糖酶活性呈显著正相关,与土壤放线菌数量呈显著负相关;多酚氧化酶活性与蔗糖酶活性呈显著负相关,与细菌、真菌、放线菌以及微生物总数呈显著正相关;放线菌只与蛋白酶、多酚氧化酶、蔗糖酶3种酶活性及真菌呈显著相关,与过氧化氢酶、酸性磷酸酶以及细菌和微生物总数的相关性均不显著.     

伊贝根际微生物分布与西贝素的相关性

分析了伊犁贝母不同生育期(返青期、显蕾期、盛花期和收获期)根际、非根际可培养土壤微生物动态变化,探讨了根际土壤微生物与西贝素含量之间的相关性。结果表明,在伊犁贝母的生长发育期,根际和非根际土壤微生物数量的分布规律是:细菌放线菌真菌。除了显蕾期非根际真菌数量大于根际以外,其他生长时期根际细菌、放线菌和真菌数量远远大于非根际,细菌根际效益明显。盛花期根际土壤中细菌和真菌数量达到了最多。土壤真菌与西贝素含量呈极显著正相关。     

异丙甲草胺对芹菜根际与非根际生物活性的影响

通过根际袋法土培试验,研究了异丙甲草胺对芹菜根际与非根际土壤酶活性、土壤微生物数量的影响以及异丙甲草胺在根际与非根际土壤中的降解特性.结果表明,异丙甲草胺对土壤过氧化氢酶活性有一定的抑制作用,对土壤脱氢酶活性有激活作用.一般情况下根际土壤酶活性均要大于非根际土壤.异丙甲草胺作用45 d后,芹菜根际土壤细菌、真菌数量大于非根际土壤,根际效应R/S在1.76～2.51之间;异丙甲草胺对土壤放线菌数量影响不大,根际效应不明显.异丙甲草胺在根际土壤与非根际土壤中的降解速率分别为0.0217和0.0176,相应的半衰期分别为31.9和39.4 d.在根际土壤中异丙甲草胺更易降解.     

石油污染土壤修复植物的根-土界面微生物特征

选取沈抚灌区的主要修复植物蓖麻为实验材料,分析了蓖麻根区土壤、根际土壤、根面、根内4个层面上细菌和真菌的数量,优势菌种的生理生化特征,及细菌菌株生长营养类型,揭示了根-土界面微生物区系特征与石油污染土壤生物修复的关系.结果发现：修复植物根-土界面上,细菌数量为根际>根面>根内,真菌数量为根内>根面>根际,根面细菌与真菌数量均处于根际与根内区域微生物数量之间;修复植物蓖麻根面区域优势细菌种类最多,根内区域优势真菌种类最多;根际与根内的优势细菌具有较强的降解大分子物质的能力;根面细菌在营养需求分类上可归为氨基酸需求菌群.     

施N对不同水稻品种N肥利用率及根际硝化作用和硝化微生物的影响

发生在水稻根际的硝化作用对水稻的氮素（N）营养受到人们越来越大的关注。在田间条件下研究了不同N效率粳稻品种（4007、武运粳7号和Elio）在无肥（0kgN/hm^2）、中肥（180kgN/hm^2）和高肥（300kgN/hm^2）水平下籽粒产量、吸N量、N肥利用率、根际土壤铵态氮（NH4^＋-N）和硝态氮（NO3^--N）含量、硝化强度和氨氧化细菌（AOB）数量。结果表明不同水稻品种的籽粒产量在3个N处理中差异极显著,4007在中肥处理中获得最高产量11117kg/hm^2,而Eilo在所有处理中籽粒产量均最低。各品种地上部吸N量随施N量增加而增加,但各品种之间差异不显著。不同水稻品种N肥利用率差异显著,4007显著高于武运粳7号和Elio。本试验根据不同品种水稻在不施N肥水平下的籽粒产量与N肥利用率的大小,将3个品种分为N肥高效敏感型（4007）、N肥高效不敏感型（武运粳7号）和N肥低效不敏感型（Elio）。在水稻中后期干湿交替的水分管理条件下,无肥和中肥区的水稻根际土壤以NO3^--N为主;而在高肥区则以NH4^＋-N为主。随着施N量增加,水稻根际土壤铵、硝态N含量也随之增加。NH4^＋-N含量在无肥、中肥和高肥水平下分别为0.88、0.94mg/kg和13.5mg/kg,而NO3^--N含量分别为1.61、1.73mg/kg和2.33mg/kg。不同水稻品种根际土壤硝化强度之间差异极显著,在3个施N水平下均表现为4007〉武运粳7号〉Elio。其平均值分别为6.94、5.46μg/（kg·h）和2.42μg/（kg·h）。在3个施N水平下,Elio根际土壤AOB数量均显著低于4007和武运粳7号。4007根际土壤AOB数量在高肥水平下达最大值2.02×106个/g土,而最小值为中肥水平下Elio的根际土壤（1.89×105个/g土）。相关性分析表明,水稻根际土壤硝化强度在无肥、中肥和高肥条件下与产量呈极显著正相关关系（r=0.799,0.877,0.934）,而且在中肥条件下与水稻N肥利用率显著相关（r=0.735）。水稻根际土壤AOB数量分别和硝化强度以及水稻籽粒产量呈极显著正相关关系。试验结果表明,水稻根际的硝化作用较大程度上决定着水稻籽粒产量或水稻N肥利用率。     

荒漠草原区土壤粒径组成对柠条根际土壤微生物数量及酶活性的影响

柠条(Caragana korshinskii)是荒漠草原区主要的造林绿化树种,研究其根际土壤微生物和酶活性与不同土壤类型土壤粒径组成的关系有重要意义,然而土壤粒径对荒漠草原柠条根际土壤微生物数量和酶活性的影响知之甚少,探讨土壤颗粒组分与微生物数量、土壤酶活性之间的关系,以及土壤颗粒组成对荒漠草原区固沙灌木植物柠条根际土壤微生物数量及酶活性的影响,可为揭示荒漠草原土壤退化及生态修复提供参考。以宁夏荒漠草原区土壤粒径组成差异显著的灰钙土、红黏土、风沙土环境下栽植的柠条为研究对象,研究不同土壤颗粒组成对根际土壤微生物数量及酶活性的相互关系与影响。结果表明:土壤微生物的数量表现为细菌放线菌真菌。根际土壤中的细菌、真菌数量显著高于非根际,且在3种不同类型的土壤中随着细砂粒的增多,真菌和放线菌数量逐渐降低,而细菌数量呈先增大后减小的趋势;根际与非根际土壤的蔗糖酶、碱性磷酸酶及过氧化氢酶活性均呈现出灰钙土红黏土风沙土的趋势,红黏土根际土壤中的脲酶活性显著高于灰钙土与风沙土;除过氧化氢酶外,土壤酶活性表现为根际高于非根际,在3种不同类型的土壤中随着细砂含量的增加,土壤酶活性均呈递减趋势。土壤颗粒组成与微生物数量之间没有明显的相关性,而与土壤酶活性之间显著相关,土壤酶活性与黏粒、粉粒呈正相关,与细砂、中砂呈负相关关系,根际土壤中酶活性更高,能够为植物及微生物提供更多的营养。     

土壤中多环芳烃的微生物降解及土壤细菌种群多样性

利用室内模拟方法,研究中、低浓度多环芳烃(PAHs)污染土壤的微生物修复效果,阐明土壤微生物（接种和土著）与PAHs降解的关系.结果表明:投加PAHs高效降解菌可以促进土壤中PAHs的降解,2周内效果显著;典型PAHs降解的难易程度依据为：菲<蒽<芘<苯并(a)芘和屈;细菌种群丰度和多样性均与PAHs降解呈负相关关系,同一处理细菌种群结构随时间变化不大.对于中、低浓度PAHs原位污染土壤,增强土著菌的活性是提高土壤PAHs降解率的有效途径之一.     

内蒙草原不同植物功能群及物种对土壤微生物组成的影响

为了分析不同植物群落组成对内蒙古典型草原土壤微生物群落组成的影响,本研究利用植物功能群剔除处理实验平台,采用荧光定量PCR(real-timePCR)和自动核糖体间隔区基因分析(automated ribosomal intergenic spacer analysis,ARISA)技术,对不同植物功能群组成的非根际土壤和常见物种的根际土壤中细菌和真菌的数量及群落结构进行了分析。结果表明,在非根际土壤中,不同植物功能群组成对细菌数量有显著影响,而对真菌数量及细菌和真菌的群落结构影响不明显;在根际土壤中,不同植物物种对细菌、真菌的数量都有显著影响。此外,聚类分析表明,不同物种的根际土中细菌和真菌的群落结构也有所不同,尤其以细菌的群落结构变化较为明显。研究结果表明不同植物物种可以通过根系影响土壤微生物群落组成。     

不同施肥处理下水稻根际和非根际土壤中氨基糖积累特征

以水稻长期定位施肥试验土壤为研究对象,选取不施肥(CK)、化肥(NPK)、秸秆还田+化肥(NPKS)、30%有机肥+70%化肥(LOM)和60%有机肥+40%化肥(HOM)5种处理,分析水稻分蘖旺期根际土和非根际土中氨基糖积累特征.结果表明: 与CK和NPK处理相比,长期施用有机物料(NPKS、LOM、HOM)显著增加了水稻根际土和非根际土中有机碳、总氨基糖及其氨基单糖(胞壁酸、氨基葡萄糖和氨基半乳糖)含量.不同施肥处理下3种氨基单糖的积累规律不同,说明不同微生物对施肥处理的响应趋势和强度有所不同.受稻田翻耕等均匀化土壤的农事操作影响,各处理总氨基糖含量在根际土与非根际土间无显著差异.氨基糖碳对土壤有机碳积累的贡献范围为24.0～28.3 mg·g^-1,且以NPKS处理最高,HOM和CK处理最低.真菌氨基葡萄糖/胞壁酸比值范围为24.4～36.6,说明该试验点所有处理的根际土与非根际土中有机质的降解与转化过程以真菌为主导,且与NPK和CK相比,NPKS处理的真菌参与度提高,而施用HOM处理的细菌参与度提高.     

长期施肥对双季稻田土壤微生物学特性的影响

为探明不同施肥处理对早稻和晚稻各个生育时期稻田土壤微生物生物量碳、氮和微生物熵的影响,以湖南宁乡长期定位试验为平台,应用氯仿熏蒸-K_2SO_4提取法和化学分析法系统分析了定位长达29年5种施肥处理之间(化肥、秸秆还田+化肥、30%有机肥+70%化肥、60%有机肥+40%化肥和无肥)双季稻田土壤微生物生物量碳、氮和微生物熵的差异。结果表明,早稻和晚稻各主要生育时期,长期施肥均能提高土壤微生物生物量碳、氮含量和微生物熵,各施肥处理土壤微生物生物量碳、氮含量和微生物熵均随水稻生育期推进呈先增加后降低的变化趋势,均于齐穗期达到最大值,成熟期达到最低值;其中,以60%有机肥和30%有机肥处理双季稻田土壤微生物生物量碳、氮含量和微生物熵均为最高,均显著高于其他处理,其大小顺序表现为60%有机肥30%有机肥秸秆还田化肥无肥。长期有机无机配施可以提高土壤微生物生物量碳、氮和微生物熵,有机肥与化肥配施对提高土壤肥力效果最好。土壤微生物生物量碳、氮及微生物熵可以反映土壤质量的变化,可作为评价土壤肥力的生物学指标。     

施肥对巢湖流域稻季氨挥发损失的影响

采用通气法对巢湖流域稻季土壤氨挥发原位监测,研究了不同施肥量及秸秆还田处理对稻季氨挥发的影响。结果表明,氨挥发峰值发生在施肥后的第1-3 天,氨挥发损失主要集中于施肥后的1周。2010年整个稻季氨挥发净损失量为7.22-14.20 kg/hm²,占氮肥施用量的4.59%-6.64%,基肥期是主要的氨挥发时期,约占总氨挥发量的60%,穗肥期氨挥发总损失量最小。常规施肥处理氨挥发总损失量最大,与常规施肥相比,优化施肥、减量化施肥均能减少稻田土壤氨挥发损失1%-2%,氮磷肥减量同时秸秆还田处理氨挥发量最小,其总氨挥发量占常规处理的54%。施肥后的1-2d内田面水中的NH₄⁺-N浓度达到最大值,且各施肥处理的氨挥发量与同期田面水中的NH₄⁺-N浓度呈线性正相关。结合经济效益和环境效应分析发现,秸秆还田处理可减少氨挥发损失,同时获得较高的经济效益,适宜在巢湖流域水稻季推广。     

Mobilizing agents enhance fungal degradation of polycyclic aromatic hydrocarbons and affect diversity of indigenous bacteria in soil

The impact of several mobilizing agents (MAs) (i.e., soybean oil, Tween-20, Tween-80, olive-oil mill wastewaters, and randomly methylated beta-cyclodextrins) on the degradation performances of the white-rot fungi Irpex lacteus and Pleurotus ostreatus was comparatively assessed in a soil spiked with a mixture of seven polycyclic aromatic hydrocarbons (PAHs). Among the different MAs, soybean oil best supported the growth of both fungi that was twice that observed in soil in the absence of MAs. In addition, soybean oil positively affected PAH degradation by both fungi. In this case, the total weight of organic contaminants (TWOC) was lower than that in the absence of MAs (57.7 vs. 201.3 and 26.3 vs. 160.4 mg kg(-1) with I. lacteus and P. ostreatus, respectively). On the other hand, the number of cultivable heterotrophic bacteria was significantly lower in the soil with soybean oil augmented with either one of the two fungi (5.21 vs. 8.71 and 0.22 vs. 0.51 x 10(7) CFU g(-1) soil with I. lacteus and P. ostreatus, respectively). The effect of soybean oil was confirmed by denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rRNA genes that showed a general decrease in biodiversity. The impact of the other MAs on bacterial diversity was either slightly negative or positive in incubation controls. Both richness and Shannon-Weaver index decreased upon treatment with P. ostreatus. Moreover, with this fungus the composition of the indigenous bacteria was not significantly affected by the type of MA used. By contrast, both indices increased in soil with I. lacteus in the presence of randomly methylated beta-cyclodextrins (39 vs. 33 and 1.43 vs. 1.26, respectively) and soybean oil (19 vs. 5 and 1.01 vs. 0.65, respectively).     

Comparison of crop productivity and soil microbial activity among different fertilization patterns in red upland and paddy soils

Soil enzyme activity and microorganism community can be changed through different long-term fertilization patterns. However, the effect of different fertilization practices on soil microorganisms might differ among crop systems. The objective of the study was to reveal the change of soil enzyme activity and soil microorganism community in different fertilizations both in upland and paddy soils. Therefore, based on long-term fertilization experiments in upland soil started in 1986 and adjacent paddy soil experiment commenced in 1981, with both consisting of 4 treatments: Control (no fertilization), N (only nitrogen fertilizer), NPK (nitrogen, phosphate and potassium fertilizers) and NPKM (nitrogen, phosphate and potassium fertilizers plus organic manure), grain yield, soil fertility, activities of soil urease, catalase, acid phosphatase, microorganism community (the number of bacteria, fungus and actinomycete) were analyzed. The result showed that: the highest grain yield was attained under the application of chemical fertilizers plus manure, as compared with Control, NPKM significantly increased the grain yield by 908.63% in corn and 118.80% in rice (p < 0.05). Meanwhile, NPKM treatment increased significantly soil organic matter and nutrient contents in upland and paddy soils. Interestingly, there was no significant difference in soil pH among all the treatments of paddy soil, but in upland, NPKM increased pH in comparison to Control by 23.06% (1.15 units of pH). Compared with Control, soil urease, catalase activities, bacteria and actinomycete numbers of NPKM were increased by 321.39%, 129.64%, 229.79%, 85.81% in upland soil, and 25.11%, 251.12%, 292.83%, 196.34% in paddy soil. However, in paddy soil, the soil acid phosphatase activity of Control, NPK and NPKM treatments were higher than upland soil by 34.87%, 44.81%, 52.73% and 30.11%. Then, the soil fungus and actinomycete numbers of paddy soil were lower than upland soil by 20.20% and 88.29%. Therefore, it indicated that long-term application of chemical and organic fertilizers delivered highest productivity in both experiment but the effect of fertilizer practices differed between land uses.     

Long-term field fertilization alters the diversity of autotrophic bacteria based on the ribulose-1,5-biphosphate carboxylase/oxygenase (RubisCO) large-subunit genes in paddy soil

Carbon dioxide (CO₂) assimilation by autotrophic bacteria is an important process in the soil carbon cycle with major environmental implications. The long-term impact of fertilizer on CO₂ assimilation in the bacterial community of paddy soils remains poorly understood. To narrow this knowledge gap, the composition and abundance of CO₂-assimilating bacteria were investigated using terminal restriction fragment length polymorphism and quantitative PCR of the cbbL gene [that encodes ribulose-1,5-biphosphate carboxylase/oxygenase (RubisCO)] in paddy soils. Soils from three stations in subtropical China were used. Each station is part of a long-term fertilization experiment with three treatments: no fertilizer (CK), chemical fertilizers (NPK), and NPK combined with rice straw (NPKM). At all of the stations, the cbbL-containing bacterial communities were dominated by facultative autotrophic bacteria such as Rhodopseudomonas palustris, Bradyrhizobium japonicum, and Ralstonia eutropha. The community composition in the fertilized soil (NPK and NPKM) was distinct from that in unfertilized soil (CK). The bacterial cbbL abundance (3–8?×?10⁸ copies g soil^?1) and RubisCO activity (0.40–1.76 nmol CO₂ g soil^?1 min^?1) in paddy soils were significantly positively correlated, and both increased with the addition of fertilizer. Among the measured soil parameters, soil organic carbon and pH were the most significant factors influencing the community composition, abundance, and activity of the cbbL-containing bacteria. These results suggest that long-term fertilization has a strong impact on the activity and community of cbbL-containing bacterial populations in paddy soils, especially when straw is combined with chemical fertilizers.     

长期不同施肥模式对南方双季稻田生态系统净碳汇效应和经济收益的影响

施肥措施与稻田生态系统净碳汇效应、经济收益的关系密切。本研究以长期(35年)定位施肥试验田为平台,分析了单独施用化肥(MF)、秸秆还田+化肥(RF)、30%有机肥+70%化肥(OM)和无肥对照(CK)4种不同施肥模式对我国南方双季稻田耕层土壤固碳速率、碳密度、年碳汇平衡和经济收益的影响。研究表明: 不同施肥处理双季稻田耕层土壤碳库变化范围为216.02～866.74 kg·hm^-2·a^-1,OM处理土壤碳年变化量显著高于MF、RF和CK处理;双季稻田土壤固碳速率为51.5～650.7 kg·hm^-2·a^-1,表土碳密度为55.64～78.42 t·hm^-2,各施肥处理高低顺序均为OM>RF>MF>CK。各施肥处理双季稻田生态系统水稻的碳吸收为4.42～9.32 t C·hm^-2·a^-1,其高低顺序为OM>RF>MF>CK;与MF处理相比,OM和RF处理稻田土壤净碳汇量分别提高了27.6%和13.6%。各施肥处理双季稻田生态系统的碳成本物质投入变化范围为1.49～2.17 t C·hm^-2·a^-1,年经济收益变化范围为1.30×10³～7.83×10³元·hm^-2·a^-1,其高低顺序为RF>OM>MF>CK;OM、RF和MF处理双季稻田生态系统经济效益的净收益均显著高于CK处理。总之,长期施用有机肥、秸秆还田配施化肥措施均有利于增加双季稻田土壤固碳速率、碳汇效应和经济收益,是提高南方双季稻田土壤有机碳贮量的施肥模式。     

Long‐term balanced fertilization increases the soil microbial functional diversity in a phosphorus‐limited paddy soil

The influence of long‐term chemical fertilization on soil microbial communities has been one of the frontier topics of agricultural and environmental sciences and is critical for linking soil microbial flora with soil functions. In this study, 16S rRNA gene pyrosequencing and a functional gene array, geochip 4.0, were used to investigate the shifts in microbial composition and functional gene structure in paddy soils with different fertilization treatments over a 22‐year period. These included a control without fertilizers; chemical nitrogen fertilizer (N); N and phosphate (NP); N and potassium (NK); and N, P and K (NPK). Based on 16S rRNA gene data, both species evenness and key genera were affected by P fertilization. Functional gene array‐based analysis revealed that long‐term fertilization significantly changed the overall microbial functional structures. Chemical fertilization significantly increased the diversity and abundance of most genes involved in C, N, P and S cycling, especially for the treatments NK and NPK. Significant correlations were found among functional gene structure and abundance, related soil enzymatic activities and rice yield, suggesting that a fertilizer‐induced shift in the microbial community may accelerate the nutrient turnover in soil, which in turn influenced rice growth. The effect of N fertilization on soil microbial functional genes was mitigated by the addition of P fertilizer in this P‐limited paddy soil, suggesting that balanced chemical fertilization is beneficial to the soil microbial community and its functions.