{"title":"泥炭土中泥炭菌的生化成分与持久性","authors":"Gwendolyn T. Pipes, J. Yavitt","doi":"10.1139/cjss-2021-0137","DOIUrl":null,"url":null,"abstract":"Abstract The amounts and arrangements of polysaccharides (cellulose and hemicellulose), proteins, phenolic lignin, and pectin that make up plant tissue, in part, determine its decay rate. Lignin-rich and/or nitrogen-poor tissue has been described as biochemically recalcitrant causing a slow decay rate. Although a controversial mechanism for organic matter storage in soils with mineral particles, biochemical recalcitrance is still poorly understood in organic peat soil (Histosols). To investigate the role of Sphagnum in formation of peat soil, we characterize biochemical components for 10 species and examine persistence of the components in soil to 150 cm depth in three peatland ecosystems. We hypothesize that species from hummock microforms have more biochemical structural components and cohesion than species from hollows. Relative proportions of biochemical components changed markedly between plant material and the top 10 cm of peat soil, suggesting that decomposition occurred at the peat soil surface, but thereafter relative proportions of biochemical components did not vary significantly to 150 cm deep. A few differences in biochemical components that distinguished hummock species from hollow species persisted to the deepest depth sampled. Although persistence of the lignin-like component was expected, persistence of soluble and ionically bound pectin compounds was surprising as these biopolymers are thought to be readily decomposable. Our findings indicate that structural components of Sphagnum, specifically polysaccharides and pectin in addition to oft-cited phenolic lignin-like components, persist in peat soil and should not be overlooked in trying to understand carbon dynamics in Sphagnum-dominated ecosystems.","PeriodicalId":9384,"journal":{"name":"Canadian Journal of Soil Science","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2022-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Biochemical components of Sphagnum and persistence in peat soil\",\"authors\":\"Gwendolyn T. Pipes, J. Yavitt\",\"doi\":\"10.1139/cjss-2021-0137\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Abstract The amounts and arrangements of polysaccharides (cellulose and hemicellulose), proteins, phenolic lignin, and pectin that make up plant tissue, in part, determine its decay rate. Lignin-rich and/or nitrogen-poor tissue has been described as biochemically recalcitrant causing a slow decay rate. Although a controversial mechanism for organic matter storage in soils with mineral particles, biochemical recalcitrance is still poorly understood in organic peat soil (Histosols). To investigate the role of Sphagnum in formation of peat soil, we characterize biochemical components for 10 species and examine persistence of the components in soil to 150 cm depth in three peatland ecosystems. We hypothesize that species from hummock microforms have more biochemical structural components and cohesion than species from hollows. Relative proportions of biochemical components changed markedly between plant material and the top 10 cm of peat soil, suggesting that decomposition occurred at the peat soil surface, but thereafter relative proportions of biochemical components did not vary significantly to 150 cm deep. A few differences in biochemical components that distinguished hummock species from hollow species persisted to the deepest depth sampled. Although persistence of the lignin-like component was expected, persistence of soluble and ionically bound pectin compounds was surprising as these biopolymers are thought to be readily decomposable. Our findings indicate that structural components of Sphagnum, specifically polysaccharides and pectin in addition to oft-cited phenolic lignin-like components, persist in peat soil and should not be overlooked in trying to understand carbon dynamics in Sphagnum-dominated ecosystems.\",\"PeriodicalId\":9384,\"journal\":{\"name\":\"Canadian Journal of Soil Science\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.5000,\"publicationDate\":\"2022-04-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Canadian Journal of Soil Science\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://doi.org/10.1139/cjss-2021-0137\",\"RegionNum\":4,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"SOIL SCIENCE\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Canadian Journal of Soil Science","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1139/cjss-2021-0137","RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"SOIL SCIENCE","Score":null,"Total":0}
Biochemical components of Sphagnum and persistence in peat soil
Abstract The amounts and arrangements of polysaccharides (cellulose and hemicellulose), proteins, phenolic lignin, and pectin that make up plant tissue, in part, determine its decay rate. Lignin-rich and/or nitrogen-poor tissue has been described as biochemically recalcitrant causing a slow decay rate. Although a controversial mechanism for organic matter storage in soils with mineral particles, biochemical recalcitrance is still poorly understood in organic peat soil (Histosols). To investigate the role of Sphagnum in formation of peat soil, we characterize biochemical components for 10 species and examine persistence of the components in soil to 150 cm depth in three peatland ecosystems. We hypothesize that species from hummock microforms have more biochemical structural components and cohesion than species from hollows. Relative proportions of biochemical components changed markedly between plant material and the top 10 cm of peat soil, suggesting that decomposition occurred at the peat soil surface, but thereafter relative proportions of biochemical components did not vary significantly to 150 cm deep. A few differences in biochemical components that distinguished hummock species from hollow species persisted to the deepest depth sampled. Although persistence of the lignin-like component was expected, persistence of soluble and ionically bound pectin compounds was surprising as these biopolymers are thought to be readily decomposable. Our findings indicate that structural components of Sphagnum, specifically polysaccharides and pectin in addition to oft-cited phenolic lignin-like components, persist in peat soil and should not be overlooked in trying to understand carbon dynamics in Sphagnum-dominated ecosystems.
期刊介绍:
The Canadian Journal of Soil Science is an international peer-reviewed journal published in cooperation with the Canadian Society of Soil Science. The journal publishes original research on the use, management, structure and development of soils and draws from the disciplines of soil science, agrometeorology, ecology, agricultural engineering, environmental science, hydrology, forestry, geology, geography and climatology. Research is published in a number of topic sections including: agrometeorology; ecology, biological processes and plant interactions; composition and chemical processes; physical processes and interfaces; genesis, landscape processes and relationships; contamination and environmental stewardship; and management for agricultural, forestry and urban uses.