不同滴灌带布设方式对苹果-大豆间作系统土壤化感物质与微生物的影响

为探究不同滴灌带布设方式对果农间作系统土壤酚酸类物质、酶活性和微生物分布特性影响，初步探明间作滴灌条件下，土壤酚酸类物质与土壤生物因子的相互关系。以晋西黄土区典型的苹果—大豆间作系统为研究对象，设置3种(L1、L2、L3)滴灌带间距，分析不同水分分布下土壤酚酸类物质、酶活性和微生物数量的空间分布变化，并在相关性基础上利用逐步回归模型，分析3个土壤因子之间的相互关系。结果表明：除苯甲酸和间苯三酚外，滴灌带间距对酚酸类物质分布影响显著(p<0.05),除过氧化氢酶外，滴灌带间距对酶活性、微生物数量分布有显著影响(p<0.05)。在垂直方向上，不同滴灌带布设方式使酚酸更多地分布在深层土壤，微生物数量和部分酶活性在L1、L2处理中随土层加深而先减后增；在水平方向上，不同滴灌带布设方式对土壤酚酸类物质、细菌和真菌分布影响与间作对照处理一致，随距树距离增加而增加。滴灌条件下，除对羟基苯甲酸外，酚酸类物质受脲酶、过氧化氢酶和放线菌的抑制作用显著，间作处理土壤酚酸总量较单作有所减少。L1处理土壤酶活性、微生物总量最高，L2处理土壤酚酸类物质累积量最低。其中L2处理在酚酸累积量最低的基础上，...

Effects of Different Drip Irrigation Belt Layout Modes on Soil Allelopathic Substances and Microorganisms in Apple-Soybean Intercropping System

To investigate the effects of different drip irrigation belt layout modes on the distribution of soil phenolic acids, enzyme activities, and microorganisms in the fruit characteristics-crop intercropping system, and to preliminarily explore the relationship between soil phenolic acids and soil biological factors under intercropping drip irrigation conditions, a typical apple (Malus pumila L.)-soybean (Glycine max L.) intercropping system in the loess region of western Shanxi was used was the research object, with three types of drip irrigation belt spacing (L1, L2, L3). The spatial distribution changes of soil phenolic substances, enzyme activity, and microbial quantity under different water distributions were analyzed, and based on this, stepwise regression model was used to analyze the interrelationships among these three soil factors. The results showed that except for benzoic acid and phloroglucinol, the distance between drip irrigation belts had a significant impact on the distribution of phenolic acids (p<0.05), and had a significant impact on the enzyme activity and the distribution of microbial population except for catalase (p<0.05). In the vertical direction, different drip irrigation belt layout modes resulted in more distribution of phenolic acids in deep soil, the number of microorganisms and some enzyme activities first decreased and then increased with the deepening of soil layer in L1 and L2 treatments; In the horizontal direction, the effects of different drip irrigation belt layout modes on the distribution of soil phenolic acids, bacteria, and fungi were consistent with the intercropping control treatment, increasing with the increase of distance from the tree. Under the condition of drip irrigation, phenolic acids except p-hydroxybenzoic acid were significantly inhibited by urease, catalase and actinomycetes, and the total amount of phenolic acids in intercropping soil was less than that in monocropping. L1 treatment had the highest soil enzyme activity and total microbial biomass, while L2 treatment had the lowest accumulation of phenolic acids in the soil. Among them, L2 treatment had a relatively high level of soil enzyme activity on the basis of the lowest accumulation of phenolic acids. Therefore, it is recommended to adopt the pattern of arrange a drip irrigation belt at intervals of one row of soybean in the fruit-crop intercropping system, improving the soil micro-ecological environment can alleviate the inhibition of allelochemicals at the same time.