Scholarlink

Purpose <p>Microbial metabolism plays a central role in regulating soil nutrient cycling and energy flow and is strongly constrained by resource availability. The transition from a traditional rice monoculture (RM) system to a rice–crayfish (RC) co-culture system substantially alters soil nutrient conditions, potentially influencing microbial carbon and nutrient limitations by reshaping microbial nutrient-acquisition strategies. However, the characteristics of microbial nutrient limitation under long-term RC co-culture systems remain poorly understood.</p> Methods <p>To quantify microbial nutrient limitation under long-term RC co-culture, a space-for-time substitution approach was applied across RM and RC systems with cultivation histories of 1, 6, 10, and 15 years. Eco-enzymatic stoichiometry was combined with vector analysis to provide a mechanistic evaluation of microbial nutrient limitation.</p> Results <p>Soil enzymatic activities in long-term RC co-culture systems (10 and 15 years) were significantly lower than those observed in the RM system. Activities of β-1,4-glucosidase, leucine aminopeptidase, and β-1,4-N-acetylglucosaminidase declined with prolonged RC co-culture, whereas alkaline phosphatase activity in the 10- and 15-year systems was significantly higher than that in the 6-year RC system. Vector threshold element ratio analysis indicated that microbial nutrient metabolism in long-term RC systems was primarily limited by phosphorus, while microbial carbon limitation was alleviated, particularly in the 15-year system. Correlation analysis further demonstrated that microbial nutrient limitation was significantly influenced by soil moisture, bulk density, pH, nutrient status, and their stoichiometric relationships.</p> Conclusion <p>Overall, the long-term rice-crayfish farming system could alleviate microbial carbon limitations, promoting soil carbon accumulation. However, it is still important to pay attention to the intensification of soil microbial phosphorus limitation in the long-term rice-crayfish farming system, which may ultimately hinder efficient soil phosphorus cycling. Based on these results, it is necessary to optimize the inputs of fertilizers (slow-release phosphate fertilizers) and feed (reduced appropriately) to ensure the stoichiometric balance of soil microbial nutrients, thereby enhancing the nutrient storage capacity of the rice-crayfish co-culture system.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Long-term rice-crayfish co-culture alleviates microbial C limitation but intensifies P limitation: Evidence from eco-enzymatic stoichiometry

  • 期刊论文

  • 发表日期：

    2026年4月2日

查看全文
  • Linsen Du,
  • Zhen Zhang,
  • Geng Sun,
  • Hua Wang

摘要

Purpose

Microbial metabolism plays a central role in regulating soil nutrient cycling and energy flow and is strongly constrained by resource availability. The transition from a traditional rice monoculture (RM) system to a rice–crayfish (RC) co-culture system substantially alters soil nutrient conditions, potentially influencing microbial carbon and nutrient limitations by reshaping microbial nutrient-acquisition strategies. However, the characteristics of microbial nutrient limitation under long-term RC co-culture systems remain poorly understood.

Methods

To quantify microbial nutrient limitation under long-term RC co-culture, a space-for-time substitution approach was applied across RM and RC systems with cultivation histories of 1, 6, 10, and 15 years. Eco-enzymatic stoichiometry was combined with vector analysis to provide a mechanistic evaluation of microbial nutrient limitation.

Results

Soil enzymatic activities in long-term RC co-culture systems (10 and 15 years) were significantly lower than those observed in the RM system. Activities of β-1,4-glucosidase, leucine aminopeptidase, and β-1,4-N-acetylglucosaminidase declined with prolonged RC co-culture, whereas alkaline phosphatase activity in the 10- and 15-year systems was significantly higher than that in the 6-year RC system. Vector threshold element ratio analysis indicated that microbial nutrient metabolism in long-term RC systems was primarily limited by phosphorus, while microbial carbon limitation was alleviated, particularly in the 15-year system. Correlation analysis further demonstrated that microbial nutrient limitation was significantly influenced by soil moisture, bulk density, pH, nutrient status, and their stoichiometric relationships.

Conclusion

Overall, the long-term rice-crayfish farming system could alleviate microbial carbon limitations, promoting soil carbon accumulation. However, it is still important to pay attention to the intensification of soil microbial phosphorus limitation in the long-term rice-crayfish farming system, which may ultimately hinder efficient soil phosphorus cycling. Based on these results, it is necessary to optimize the inputs of fertilizers (slow-release phosphate fertilizers) and feed (reduced appropriately) to ensure the stoichiometric balance of soil microbial nutrients, thereby enhancing the nutrient storage capacity of the rice-crayfish co-culture system.