中国农业科学 ›› 2021, Vol. 54 ›› Issue (22): 4840-4850.doi: 10.3864/j.issn.0578-1752.2021.22.011

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

东北黑土线虫群落对长期免耕后土壤扰动的响应

张梦亭1,3(),刘萍1,黄丹丹1,贾淑霞1,张晓珂2,张士秀1(),梁文举2,陈学文1,张延1,梁爱珍1   

  1. 1中国科学院东北地理与农业生态研究所黑土区农业生态重点实验室,长春 130102
    2中国科学院沈阳应用生态研究所森林生态与管理重点实验室,沈阳 110016
    3中国科学院大学,北京 100049
  • 收稿日期:2020-11-25 接受日期:2021-05-06 出版日期:2021-11-16 发布日期:2021-11-19
  • 通讯作者: 张士秀
  • 作者简介:张梦亭,Tel:0431-85542234;E-mail: zhangmengting@iga.ac.cn
  • 基金资助:
    国家自然科学基金(42077046);国家自然科学基金(U20A2083);吉林省科技发展计划项目(20190201116JC);中国科学院青年创新促进会项目(2021228)

Response of Nematode Community to Soil Disturbance After Long-Term No-Tillage Practice in the Black Soil of Northeast China

ZHANG MengTing1,3(),LIU Ping1,HUANG DanDan1,JIA ShuXia1,ZHANG XiaoKe2,ZHANG ShiXiu1(),LIANG WenJu2,CHEN XueWen1,ZHANG Yan1,LIANG AiZhen1   

  1. 1Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102
    2Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016
    3University of Chinese Academy of Sciences, Beijing 100049
  • Received:2020-11-25 Accepted:2021-05-06 Online:2021-11-16 Published:2021-11-19
  • Contact: ShiXiu ZHANG

摘要:

【目的】目前对长期免耕土壤实施扰动后土壤生态系统稳定性的响应情况尚不了解。本研究选择土壤线虫作为指示生物,研究土壤线虫群落结构对长期免耕扰动前和扰动后的响应情况,为东北黑土区合理选择耕作措施提供科学依据和参考。【方法】以吉林省德惠市中国科学院东北地理与农业生态研究所黑土长期保护性耕作实验站为依托平台,分别设置长期免耕(NT)及长期免耕后扰动(DNT)两种不同免耕耕作方式;在作物播种前,采集耕层(0—15 cm)土壤,进行线虫的分离鉴定。使用效应值(lnR),以常规耕作(CT)为对照,度量不同轮作方式下(玉米-大豆轮作,CS;玉米连作,CC)长期免耕及长期免耕后扰动对土壤线虫的属数、多度和生态指数的影响效应。利用主成分分析(PCA)和冗余分析(RDA)进行土壤线虫群落组成及其驱动因子的分析。【结果】与CT相比,NT处理促进了各轮作方式下杂食/捕食线虫的多度,DNT处理显著(P<0.05)促进了玉米-大豆轮作下食细菌线虫的属数及多度、食真菌线虫和总线虫的多度,而对玉米连作下所有线虫营养类群的属数及多度具有抑制效应。NT、DNT处理的线虫群落组成与CT处理截然不同,其主要的土壤驱动因子分别是全氮含量和容重,可以解释线虫群落组成差异的10.5%和11.4%。此外,与CT相比,NT处理显著(P<0.05)促进了各轮作方式下的结构代谢足迹(Fs),而DNT处理显著(P<0.05)抑制了几乎所有生态指数(除自由生活线虫与植物寄生线虫成熟度指数比率(MI/PPI)之外)。DNT处理对土壤线虫生态指数的抑制程度因轮作方式而异,与玉米连作相比,玉米-大豆轮作仍能维持对MI/PPI的促进效应。【结论】长期免耕能够在各轮作方式下形成较为稳定的土壤线虫群落结构;深翻和移除秸秆等土壤扰动会破坏长期免耕下土壤线虫群落结构的稳定性,但破坏程度因轮作方式而异。

关键词: 耕作方式, 轮作方式, 土壤扰动, 线虫群落, 生态指数, 黑土

Abstract:

【Objective】 To date, the responses of the soil ecosystem stability to soil disturbance after long-term no-tillage practice are still unknown. In this study, soil nematodes were served as a model to study the response of soil nematode community structure to before and after disturbance under a long-term no-tillage practice, so as to provide a scientific support for the rational selection of farming measures in the black soil area of Northeast China.【Method】Two different phases of long-term no-tillage practices, including no-tillage (NT) and disturbed no-tillage (DNT), were set up on a black soil experimental station of Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Dehui City, Jilin Province. Before planting the crops, the soil samples collected from the 0-15 cm soil layer were used to isolate and identify the nematodes. Using the conventional tillage (CT) as the control, the effect value (lnR) was calculated to measure the effect size of NT and DNT on the number of genus and the abundance and ecological index of nematodes under different rotation systems (corn-soybean rotation, CS; corn continuous cropping, CC). Principal component analysis (PCA) and redundancy analysis (RDA) were used to determine the composition of soil nematode communities and their driving factors among different tillage practices.【Result】Compared with CT, NT had a positive effect on the abundance of omnivores-predators across crop rotation systems, while DNT significantly (P<0.05) improved the genus number and abundance of bacterivores, the abundance of fungivores and the total nematodes under CS, and exerted negative effects on the genus number and abundance of all nematode trophic groups under CC. The composition of nematode community of NT and DNT was completely different from that of CT, and the main driving factors were total nitrogen content and bulk density, which could explain 10.5% and 11.4% of the variation in nematode community, respectively. In addition, compared with CT, NT significantly (P<0.05) increased the value of structure footprint (Fs) across all crop rotation systems, while DNT significantly (P<0.05) decreased almost all ecological indexes (except the maturity ratio of free-living nematodes to plant-parasitic nematodes, MI/PPI). Furthermore, the decrease degree of ecological index varied with crop rotation systems. CS instead of CC exerted a significant positive effect on MI/PPI. 【Conclusion】Long-term no-tillage practice could form a relatively stable soil nematode community structure in all crop rotation systems. This stability was easily gone away with the soil disturbance, including mouldboard ploughing and the removal of residues. However, crop rotation could mitigate the instability caused by soil disturbance.

Key words: tillage system, rotation system, soil disturbance, nematode community, ecological indices, black soil