石灰土和酸性土生境下金花茶组植物叶片钙形态差异

Difference in calcium speciation in leaves of golden Camellia species from calcareous soil and acidic soil habitats

关键词:  金花茶, 土壤环境, 钙适应, 聚类分析, 喀斯特植物

Key words:  golden Camellia, soil environment, calcium adaptation, cluster analysis, karst plant

摘要:

为探究不同生境下金花茶组植物的叶片钙形态特征,该研究以10种石灰土生境和4种酸性土生境的金花茶为对象,测定了其生境土壤的钙含量和pH值,以及该生境下金花茶组植物叶中的硝酸钙和氯化钙、水溶性有机酸钙、果胶酸钙、磷酸钙和碳酸钙、草酸钙、硅酸钙和总钙的含量。结果表明:(1)石灰土生境的土壤钙含量和土壤pH均极显著(P<0.01)高于酸性土。(2)在石灰土生境中,金花茶组植物的叶钙形态以草酸钙(41.17%)为主,而在酸性土生境中则以果胶酸钙(43.10%)为主,除硝酸钙和氯化钙、果胶酸钙外,石灰土金花茶的各叶钙形态和总钙含量均极显著(P<0.01)高于酸性土金花茶。(3)相关性分析结果显示,大部分叶钙形态含量与土壤pH和土壤钙含量呈极显著(P<0.01)正相关,表明土壤环境对金花茶组植物叶钙形态特征具有重要影响。(4)单因素方差分析结果显示,各叶钙形态含量在物种间存在极显著(P<0.01)差异,表明金花茶组植物在物种分化过程中叶钙形态特征具有多样性。(5)基于叶钙形态特征的聚类分析显示,14种金花茶可归为3大类。总体而言,不同生境背景下金花茶组植物的叶钙形态差异可能是土壤环境和遗传因素共同作用的结果。该研究结果有助于深入理解金花茶组植物对土壤钙的适应机制,为其保育措施制定提供了参考。

Abstract:

In order to study the calcium speciation characteristics in leaves of golden Camellia species under different habitats, 10 species of golden Camellia from calcareous soil habitats and four species from acidic soil habitats were used as the research objects. The calcium content(Soil-Ca)and pH(Soil-pH)of habitat soil, and the contents of calcium nitrate and calcium chloride(AIC-Ca), water soluble organic acid calcium(H₂O-Ca), calcium pectate(NaCl-Ca), calcium phosphate and calcium carbonate(HAC-Ca), calcium oxalate(HCl-Ca), calcium silicate(Res-Ca), and total calcium(Tot-Ca)of leaves were measured. The results were as follows:(1)the Soil-Ca and Soil-pH of calcareous soil were extremely significantly(P<0.01)higher than those of acidic soil.(2)The leaf calcium speciation of golden Camellia species from calcareous soil habitats was primarily HCl-Ca(41.17%), while species from acidic soil habitats was primarily NaCl-Ca(43.10%), and all calcium speciation and total calcium content in leaves of species from calcareous soil were extremely significantly(P<0.01)higher than that from acidic soil except for AIC-Ca and NaCl-Ca.(3)Correlation analysis showed that most of the content of calcium speciation in leaves was extremely significantly(P<0.01)and positively correlated with Soil-Ca and Soil-pH, indicating that soil environment had an important influence on the leaf calcium speciation characteristics of golden Camellia species.(4)According to one-way ANOVA, the content of each leaf calcium speciation was extremely significant(P<0.01)difference among the species in golden Camellia revealing that the calcium speciation characteristics had a considerable variation during the species differentiation.(5)Cluster analysis based on calcium speciation characteristics showed that the 14 species of golden Camellia could be grouped into three categories. In summary, the differences in leaf calcium speciation of plants of golden Camellia species in different habitats may be the consequence of a combination of soil environmental and genetic factors. The results of this study will help to understand the adaptation mechanism of golden Camellia species to soil calcium and provide a reference for the formulation of conservation measures.