种植冬绿肥对红壤幼龄橘园土壤微生物量碳、氮和酶活的影响

Effects of Winter Green Manure Planting on Soil Microbial Biomass Carbon,Nitrogen,and Enzyme Activity in Red Soil Young Citrus Orchard

种植绿肥是培肥改良果园土壤、提高水果产量品质的有效措施。为筛选适宜江西红壤幼龄橘园种植的冬绿肥品种,在橘园行间播种毛叶苕子(Viciavillosa Roth)、肥田萝卜(Raphanus sativus)、黑麦草(Lolium perenne)、鼠茅草(Vulpia myuros)等4种冬绿肥,研究种植不同冬绿肥对土壤化学性质、微生物量碳、氮和酶活性的影响。结果表明,与自然生草相比,短期种植冬绿肥对土壤pH、有机质和全氮的影响较小,对土壤速效养分有一定的提升效果,但均未发生显著变化。种植冬绿肥明显改善了土壤生化性质,使土壤MBC和MBN分别增加47.9%-114%和75.9%-292%,使MBC/MBN降低14.2%-53.7%,其中鼠茅草和黑麦草处理效果最佳;种植冬绿肥还提高了土壤过氧化氢酶(1.70%-20.0%)、酸性磷酸酶(15.8%-78.9%)、脲酶(13.8%-46.6%)、转化酶(13.7%-55.5%)、过氧化物酶(120%-218%)、多酚氧化酶(4.70%-55.2%)等6种酶的活性,仍以鼠茅草和黑麦草的效果最佳。运用主成分分析对各处理的土壤生化性质进行综合评价,其得分排序为:鼠茅草(1.07)>黑麦草(0.93)>毛叶苕子(0.20)>肥田萝卜(−0.24)>自然生草(−2.31),进一步运用聚类分析可将其分为3类:鼠茅草和黑麦草(第Ⅰ类)、毛叶苕子和肥田萝卜(第Ⅱ类)、自然生草(第Ⅲ类)。综上,种植冬绿肥可明显改善红壤幼龄橘园的土壤肥力状况,对土壤微生物量碳、氮含量和酶活性等生化性质的提升尤为明显,在实际生产中优先推荐鼠茅草、黑麦草作为冬绿肥品种。该研究为红壤区幼龄果园的土壤肥力培育、绿色生态种植提供了技术参考,有助于南方特色水果的量质协同提升和相关产业的健康可持续发展。

Growing and utilizing green manure is an effective practice to improve orchard soil fertility and fruit yield and quality.To select the appropriate winter green manure varieties for young citrus orchard in red soil in Jiangxi Province,four different winter green manure varieties,i.e.,Viciavillosa Roth,Raphanus sativus,Lolium Perenne and Vulpia myuros,were interplanted in orange orchards.We grew different winter green manure varieties and measured soil chemical properties,microbial biomass carbon,microbial biomass nitrogen and enzyme activities.The results showed that compared with the natural weed,growing winter green manure in a short-term had less effect on soil pH,organic matter and total nitrogen,and had an improvement effect on soil available nutrients,and there was no significant effect on soil physicochemical properties.Growing winter green manure improved soil biochemical properties,increased MBC and MBN by 47.9%–114%and 75.9%–292%,respectively,decreased the ratio of MBC/MBN by 14.2%–53.7%,and Vulpia myuros and Lolium Perenne had the best effect.Growing winter green manure also improved the activities of soil enzymes,including soil catalase(1.70%–20.0%),acid phosphatase(15.8%–78.9%),urease(13.8%–46.6%),invertase(13.7%–55.5%),peroxidase(120%–218%)and polyphenol oxidase(4.70%–55.2%),and the best effect was found in Vulpia myuros and Lolium Perenne.Principal component analysis was used to comprehensively evaluate the soil biochemical properties of each treatment,and the scores were ranked as:Vulpia myuros(1.07)>Lolium perenne(0.93)>Viciavillosa Roth(0.20)>Raphanus sativus(−0.24)>natural weed(−2.31).Furthermore,the cluster analysis was used to reveal the category and that could be divided into three categories:(I)Vulpia myuros and Lolium Perenne,(II)Viciavillosa Roth and Raphanus sativus,(III)natural weed.In conclusion,growing winter green manure could significantly improve the soil fertility of young orange orchard in red soil,especially the biochemical properties,i.e.,soil microbial carbon and nitrogen concentration and enzyme activities.Vulpia myuros and Lolium perenne are recommended as winter green manure in practice.This study provides a technical reference for soil fertility and green ecological cultivation of young orchards in the red soil region,and could contribute to the coordinated improvement of the quality of characteristic fruits in South China and the healthy and sustainable development of related industries.