基于叶片及土壤分析的古树精准复壮研究——以粤北地区典型衰弱古树为例

Research on Accurate Rejuvenation Technology of Ancient Trees Based on Leaf and Soil Analysis:A Case Study of Typical Weakened Ancient Trees in Northern Guangdong

为了解古树的衰弱成因,制定科学的复壮措施,测定和分析衰弱古树绿叶和凋落叶的养分含量、土壤养分含量以及土壤重金属含量是有效途径。通过对粤北地区的苦槠Castanopsis sclerophylla、榕Ficus microcarpa、秋枫Bischofia javanica、樟Cinnamomum camphora和雅榕Ficus concinna等5株典型高龄古树衰弱株的抽样调查得知:1)5株衰弱古树的绿叶与凋落叶养分含量(N、P、K、Ca、Mg、S)与健康株相比,养分含量较低且各具差异性;2)除樟树外其余4株古树土壤养分含量(全N、全P、全K、碱解N、有效P、有效K)均处于缺乏水平。3)抽样调查证实了土壤重金属超标,可能会加剧一些古树的衰老。古树的精准复壮方案应按照不同衰弱树种营养元素含量水平制定,采取相应措施,如给古树补充相应的营养液、施加有机肥、更换肥土等,同时防控土壤重金属污染。

To develop scientific measures for the rejuvenation of weakened ancient trees,it is necessary to first understand the causes behind their debilitation.This involves determining and analyzing the nutrient content,soil nutrient content,and heavy metal levels of both green and fallen leaves.In our study,we conducted a sampling survey of five typical ancient tree species,namely Castanopsis sclerophylla,Ficus microcarpa,Bischofia javanica,Cinnamomum camphora,and Ficus concinna,in northern Guangdong.Our findings indicate that:1)The nutrient content(N,P,K,Ca,Mg,S)of green and fallen leaves of the five weakened ancient trees was lower and different than that of healthy plants.2)The soil nutrient content(total N,total P,total K,alkaline N,available P,and available K)of four out of the five ancient trees,except Cinnamomum camphora,was deficient.3)Our sampling surveys confirmed that soil heavy metal levels exceeded the standard,which may accelerate the aging process of some ancient trees.Therefore,in order to create precise rejuvenation plans for different weakened ancient tree species,it is important to consider their individual nutrient content levels.Corresponding measures should be taken,such as supplementing ancient trees with nutrient solutions,applying organic fertilizer,replacing fertilized soil,and preventing and controlling soil heavy metal pollution.