| Earthworms are the important constituent parts in the soil ecosystem. During the biological cycling of the material, they have the special functional action for elements transforming, reserving and releasing. The dissertation studied on earthworms' action in the material decomposing and transforming in the Pinus koraiensis broad-leaved mixed forest in the Northeast of China. It has the scientific significance for studying on the material cycling and energy flowing of the forest ecosystem. The dissertation adopted experimentation in the laboratory and field investigation. Simulated the ecological habitat in the field and studied on the defoliation decomposing, which was ingested by earthworms. Analyzed the factors of influencing the ingestion of the earthworms. Studied the action of earthworms on the transforming Organic C and total N in the broad leaves decomposing. Discussed the function of earthworms in the material decomposing and transforming in the Pinus koraiensis broad-leaved mixed forest in the Northeast.The ingestion of earthworms varied with the temperature changing. The kind of defoliation and time of decomposing also influenced the ingestion of earthworms. The ingestion of earthworms was : 20℃ ＞25℃＞15℃. It was in the defoliation of Betula costata ＞Acer mono ＞Tilia amurensis. The average of increased weight of earthworms when they ingested decomposed defoliation was: 25℃ ＞20℃＞15℃. The longer the time of the defoliation decomposing, the ingestion of earthworms was bigger. The earthworms preferred to decomposed defoliation. The value of C/N of decomposed defoliation was lower than fresh one.After earthworms ingested the defoliations, the average of the decomposition rate of three defoliation was 20℃＞25℃＞15℃.The changing law was consistent with the ingestion of earthworms under different temperature. The average on the decomposition rate of Acer mono defoliation was the biggest of three. The one of Betula costata defoliation was the second. The one of Tilia amurensis defoliation was the smallest. The decomposition rate of defoliation didn't become bigger with the time of feeding earthworms becoming longer, when they ingested the defoliation of different decomposing time. The content of organic C in earthworms was the lowest. The one in the earthworms' feces was second. The one in the defoliation was the highest. The changing law of the content of total N of the above was contrary to the content of organic C. The content of organic C in different defoliation was: Tilia amurensis＞Betula costata＞Acer mono .The content of total N in different defoliation was: Betula costata＞Tilia amurensis＞Acer mono. The changing law about the content of organic C and total N in earthworms' feces almost was consistent with the one of defoliations. After 20 days, earthworms transformed 8.0754g～11.4733g organic N. The organic C in increasing weight of earthworms accounted for organic C of ingested defoliation by earthworms 3.90%～13.31%.The one in earthworms' feces accounted for ingested organic C 6.15%～13.70%. The respiration, activity etc. of earthworms transformed organic C, which accounted for ingested organic C 81.10%～89.95%.The total N ingested by earthworms(0.1774g～0.2641g) was fewer than organic C. Among them, 37.08% transformed into the constituent parts of increasing weight of earthworms. 19.97% transformed into the total N in earthworms' feces. 47.86% transformed into consumption of total N for earthworms' activity.The action of earthworms made the content of organic C and total N increasing in the soil. Earthworms ingested defoliation, which were decomposed and transformed in earthworms' intestine. The metabolized productions (such as earthworms' feces) were discharged. These productions increased the amount and content of organic C and total N in the soil. The action of earthworms also decreased the value of C/N in soil and defoliation. Earthworms can accelerate organic C and N in the defoliation cycling and transforming and increase the available C and...
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