本研究探討了鉻（Cr）污染對蚯蚓糞便微生物群落結構的影響及其在重金屬修復中的潛力。鉻作為一種常見的工業污染物，對人類健康和生態系統構成嚴重威脅。蚯蚓作為土壤生態系統的重要成員，在維持土壤健康和生態平衡中發揮了關鍵作用，但其對重金屬污染高度敏感。本研究選用掘穴環爪蚓（Perionyx excavatus）作為模型，分別探討了三價鉻（Cr(III)）與六價鉻（Cr(VI)）對蚯蚓及其糞便微生物群落的影響，並進一步分析蚯蚓糞便微環境中功能菌的增殖與鉻還原能力。
實驗結果顯示，Cr(VI) 的暴露降低了蚯蚓的存活率與體重增長，對照組、Cr(III) 組和 Cr(VI) 組的存活率分別為 100%、97.78% 和 75.56%，而 Cr(VI) 組的蚯蚓體重則明顯下降，顯示出 Cr(VI) 的毒性作用。此外，蚯蚓體內的鉻含量低於其糞便中的鉻含量，表明蚯蚓通過活性排泄機制將鉻從體內排出。
在微生物群落結構分析中，發現含鉻處理顯著改變了蚯蚓糞便中的微生物群落，特定功能菌屬如Leucobacter和Comamonas的豐富度提高，表現出鉻還原能力，能有效將毒性的Cr(VI)還原為低毒的Cr(III)。硒（Se）的加入在某些情境下增強了微生物群落對重金屬的適應性，展現了協同修復的潛力，但在部分情況下也產生拮抗效應，削弱了微生物群落的多樣性與穩定性。此外，蚯蚓糞便提供了一個富含有機質和微量元素的特殊微環境，促進了功能菌屬如Flavobacterium和Chryseobacterium 的增殖，進一步推動了鉻的穩定化與還原。
從蚯蚓糞便中分離出的Bacillus cereus展現了卓越的鉻還原與固定能力，能在低濃度條件下高效去除Cr(VI)，顯示了其在污染修復和資源化利用中的雙重應用潛力。本研究強調蚯蚓及其微生物群落在重金屬修復中的協同作用，不僅提高了修復效率，還促進了微生物群落的穩定性與功能多樣性。未來應進一步探索蚯蚓與微生物的交互機制，特別是在多重污染環境中的應用，為可持續環境治理提供科學依據和新策略。

This study investigated the impact of chromium (Cr) contamination on earthworm fecal microbial communities and their potential for heavy metal remediation. The results showed that Cr exposure significantly altered microbial community structures, with increased abundance of functional genera such as Leucobacter and omamonas, which demonstrated the ability to reduce the highly toxic hexavalent chromium (Cr(VI)) to the less toxic trivalent chromium (Cr(III)). The addition of selenium (Se) enhanced microbial adaptability under certain conditions and exhibited synergistic remediation effects in multi-pollutant scenarios, though antagonistic interactions were also observed. Earthworm feces, as an organic matter-rich microenvironment, promoted the proliferation of functional bacteria such as Flavobacterium and Chryseobacterium, further facilitating the stabilization and reduction of Cr. Additionally, Bacillus cereus, isolated from earthworm feces, exhibited efficient Cr(VI) reduction and immobilization capabilities, demonstrating its dual potential for pollution remediation and resource recovery.This study highlights the synergistic roles of earthworms and their associated microbial communities in bioremediation, not only improving remediation efficiency but also enhancing microbial community stability and functional diversity. Future research should focus on optimizing the earthworm-microbe synergistic mechanisms to address more complex pollution scenarios and promote sustainable environmental development.

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