渤海泥质海岸典型防护林对土壤酶活性季节动态的影响

Seasonal Dynamics of Soil Enzymatic Activity in Typical Shelterbelts on the Bohai Muddy Coast

研究渤海泥质海岸白榆(Ulmus pumila)中龄林、刺槐(Robinia pseudoacacia)中龄林、白蜡(Fraxinus chinensis)中龄林、群众杨(Populus popularis)中龄林、杨树(Populus×liaoningensis)刺槐(Robinia pseudoacacia)混交林、白榆(Ulmus pumila)幼龄林、辽宁杨(Populus×liaoningensis)幼龄林及当地自然生灌草地土壤过氧化氢酶、碱性磷酸酶、脲酶、蔗糖酶活性季节动态及与土壤养分含量的关系,以期为渤海泥质海岸土壤改良和防护林科学营建提供理论依据。结果表明:在0～30cm土层内,渤海泥质海岸典型防护林土壤过氧化氢酶活性与碱性磷酸酶活性季节动态多呈现春秋两季低、夏季高的倒"V"字型变化,土壤脲酶活性季节动态多呈现春秋两季高、夏季低的"V"字型变化,蔗糖酶活性季节动态多呈现春夏秋连续升高的直线型变化。不同防护林对土壤过氧化氢酶活性影响差异显著,对土壤碱性磷酸酶、脲酶、蔗糖酶活性影响差异不显著;群众杨中龄林、杨树刺槐混交林、白榆幼龄林、辽宁杨幼龄林土壤过氧化氢酶活性均显著低于对照灌草地,分别降低了29.89%,46.81%,64.25%,38.56%。渤海泥质海岸防护林显著降低土壤pH值、电导率、土壤含水量,显著提高土壤有机碳、全氮、全磷含量。土壤碱性磷酸酶、脲酶活性与土壤电导率呈显著负相关,土壤过氧化氢酶活性与土壤含水量呈极显著正相关,土壤过氧化氢酶、碱性磷酸酶、脲酶、蔗糖酶活性与土壤有机碳、全氮、全磷存在显著正相关。

In order to provide a theoretical basis for soil improvement and scientific construction of Shelterbelts in muddy coastal areas of Bohai.,in this article,we studied the seasonal dynamics and relationship between soil nutrient content and soil catalase,alkaline phosphatase,urease,sucrase in Ulmus pumila mid-aged forest(UPM),Robinia pseudoacacia mid-aged forest(RP),Fraxinus chinensis mid-aged forest(FC),Populus popularis mid-aged forest(PP),mixed forest of Populus×liaoningensis and Robinia pseudoacacia young forest(PR),Ulmus pumila young forest(UP),Populus×liaoningensis young forest(PL)and natural shrub grassland.The results showed that the change patterns of four soil enzymatic activity from spring to autumn were diverse in Bohai muddy coast.In the 0-30 cm soil layer,the soil catalase and alkaline phosphatase activity of the muddy coast kept a lower level in spring and autumn,and they kept a higher level in summer,and the seasonal trend showed an inverted"V"character.The soil urease activity of shelterbelt kept a higher level in spring and autumn,and it kept a lower level in summer,the seasonal trend showed a"V"character.The activity of sucrase was highest in autumn and lowest in spring,the seasonal trend showed an increased straight line.There were significant differences in soil catalase activity of different shelterbelts.And the effects of different shelterbelts on soil alkaline phosphatase,urease and sucrase were not significant.The activity of catalase in soil of PP,PR,UP and PL were significantly lower than that of control irrigation grassland,which decreased by 29.89%,46.81%,64.25%,and 38.56%,respectively.Afforestation can significantly reduce soil pH,soil electrical conductivity,water content and improve soil organic carbon,total nitrogen and total phosphorus content.Soil alkaline phosphatase and urease were negatively correlated with soil electrical conductivity.Soil catalase has a very significant positive correlation with soil water content.Soil catalase,alkaline phosphatase,urease and sucrase were positively correlated with soil organic carbon,total nitrogen and total phosphorus.