冬水田稻鱼萍生态系统的探讨

AN INVESTIGATION OF THE PADDYFIELD ECOSYSTEM OF "RICE- FISH- DUCKWEED

本文概括了我们于1980—1982年,在重庆市蔡家公社进行的人为“稻、鱼、萍”生态系统的试验方法和结果。利用冬水田进行宽、窄行种植杂交中稻,其窝行距为:(15+5)×3—4寸;在水稻的宽行间开沟养鱼;并充分利用水面放养红浮萍。试验结果证明,经济效果十分显著。它可以充分利用空间、水面、水中和稻田土壤等生态因素来提高稻、鱼、萍的产量,其主要优点如: 1.采用这种宽窄行种植法的水稻产量相当于常规大田栽插法的产量,并能稳产高产。 2.此法养鱼,可延长放养时间,增加其放养密度,更有利于提高鱼的产量,并协调了稻和鱼的矛盾。 3.能充分利用水面的空闲时间和稻萍共生期的宽行间进行养萍,因此是积极挖掘肥源的重要途径。 所以,这个良好的农田结构不仅能获得稻鱼萍的高产,而且还能逐年提高土壤的肥力。因此,稻田这个生态系统值得更进一步的扩大试验和研究。

This paper sums up the results of our experiment on the "rice-fish-duckweed" artificial ecosystem at Cai Jia Commune in the suburbs of Chongqing, Sichuan, from 1980 to 1982.A wide-narrow row plantation with a distance of (50+16)×10-13cm between rows is adopted to grow hybrid midseason rice in the paddyfild for three years continuously. For the purpose of making full use of ricefield's space, fish and duckweed are raised under the rice plant. We find the economic effect of his ecosystem quite high. Its advanatges are.1 .rice yield of the wide-narrow row plantation method per unit area quite similar to that of conventional planting;2.fish production to be raised by prolonging the time and raising the density of fish breeding, thus to lessen the contradiction between rice and fish;3.manure resources well exploited by making full use of the time and space luring the growing period of rice and duckweed.So this ecosystem not only provides a satisfactory agricultural structure for a high production of rice, fish and duckweed, but also maintains the fertility of soil, aed is therefore worth further experimenting and studying.