兰州雨养生态试验示范区坡向对土壤养分特征的影响

Effects of slope aspects on soil nutrient characteristicsat rain-fed ecological experiment demonstrationsite in Lanzhou

摘要:

为了探索坡向与土壤养分含量之间的关系,为兰州市雨养生态区植被恢复与重建提供理论依据,以兰州市皋兰县水阜镇老虎台雨养生态试验示范区为试验点,测定不同坡向(阳坡、半阳坡和阴坡)土壤有机质、速效P、速效K和速效N含量,分析不同土层和坡向土壤养分含量及相互之间的相关性,综合评价土壤养分状况。结果表明:(1)土壤养分含量呈现出阴坡＞半阳坡＞阳坡,且随着土壤深度的增加呈显著下降的趋势。(2)坡向与土壤有机质和速效N含量呈显著正相关(P＜0.05);土层深度与土壤有机质、速效P,速效K和速效N含量呈显著负相关(P＜0.05);土壤有机质、速效P,速效K和速效N含量之间存在显著的正相关关系(P＜0.05)。(3)土壤有机质和速效N含量在不同土层和不同坡向间差异显著(P＜0.001),且土层和坡向交互作用对其也有显著影响(P＜0.05)。整体上土壤养分含量偏低,建议在植被恢复配置时,要适地适树,选择抗性强的植物,并适当施用有机肥料。

Abstract:

This study aimed to explore the relationship between different slope aspects and soil nutrient content,and to provide the theoretical basis for vegetation restoration and reconstruction at Lanzhou rain-fed ecological zones.The soil organic matter,available P,available K,available N,and their correlation were analyzed at different soil depth from the different slope aspects (South-facing slope,half sunny slope and North-facing slope) at the Tiger Terrace Rain-fed Ecological Experiment and Demonstration Zone,in Shuifu Township,Gaolan County,Lanzhou.The results showed that soil nutrient content decreased significantly with the increasing soil depth,and followed a trend of south-facing slope ＞ half sunny slope ＞ north-facing slope.The slope aspects had a significant and positive correlation with soil organic matter and available N content (P＜0.005).Soil depth showed a significant and negative correlation with soil organic matter,available P,available K and available N content (P＜0.005).There was a significant and positive correlation between soil organic matter,available P (P＜0.001),available K and available N (P＜0.005).Soil organic matter content and available N were significantly affected by soil depth,slope aspects (P＜0.001) and their interactions (P＜0.05).As soil nutrient content was generally low,we suggest that plants with strong resistance should be selected and planted at the suitable sites,with the appropriate application of organic fertilizers for soil rehabilitation.