渤海泥质海岸四种典型防护林对土壤微生物生物量、酶活性及土壤养分的影响

Effects of Four Typical Shelterbelts on Soil Microbial Biomass, Enzyme Activities and Soil Nutrient in the Bohai Muddy Coast

为了探究不同造林树种对泥质海岸林地土壤微生物生物量、酶活性及养分的影响,以渤海泥质海岸相同立地条件和营林方式的白榆(Ulmus pumila)纯林(UP)、刺槐(Robinia pseudoacacia)纯林(RP)、白蜡(Fraxinus chinensis)纯林(FC)、群众杨(Populus popularis)纯林(PP)为研究对象,对照当地自然生灌草地(CK),研究4种典型防护林林下土壤微生物生物量碳(SMBC)、氮(SMBN)、土壤酶活性及养分的变化。结果表明:在0~10 cm土层内,UP防护林下SMBC、SMBN含量均高于对照灌草地;在10~30 cm土层内,4种防护林SMBC含量均增加。4种防护林均降低了土壤过氧化氢酶与土壤脲酶活性。UP、RP、PP防护林下土壤碱性磷酸酶均显著高于CK,FC显著降低。UP防护林显著增加土壤蔗糖酶活性。4种防护林均显著提高土壤全磷含量,降低土壤pH值。在渤海泥质海岸防护林下,SMBC、SMBN与土壤蔗糖酶、有机碳、全氮、速效磷呈显著正相关,相关系数在0.65~0.83之间。综合分析表明,在渤海泥质海岸带,UP对土壤改良效果最佳,RP、FC、PP防护林改良效果次之。

In order to research the changes of soil microbial biomass, enzyme activities and nutrients under different shelterbehs in Bohai muddy coast, Ulmus pumila pure forest （UP）, Robinia pseudoacacia pure forest （RP）, Fraxinus chinensis pure forest （FC）, Populus popularis pure forest （PP） and natural shrub grassland （CK） were selected as the study objects. The results showed that the contents of soil microbial biomass carbon （SMBC） and nitrogen （SMBN） were higher in the UP pure forest than in CK in the 0 - 10 cm soil layer, while the content of SMBC increased in 10 - 30 cm soil layer under the four shelterbelts. The activities of soil catalase and urease decreased significantly in the four shelterbelts. The content of soil alkaline phosphatase was significantly higher under the UP, RP and PP pure forests than that in CK, while that was significantly lower under the FC pure forest. The activity of soil suerase increased significantly under the UP pure forest. The content of soil total phosphorus significantly increased, while soil pH value significantly decreased under the four shelterbelts. The contents of SMBC and SMBN were significantly positively correlated with soil sucrase, organic carbon, total nitrogen, available phosphorus under the four shelterbehs, and the correlation coefficients ranged from 0.65 to 0.85. In conclusion, the UP pure forest had the best effects on soil improvement, followed by the RP pure forest, FC pure forest and PP pure forest in the Bohai muddy coast.