Intra- versus inter-site macroscale variation in biogeochemical properties along a paddy soil chronosequence
Intra- versus inter-site macroscale variation in biogeochemical properties along a paddy soil chronosequence
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DOI：
10.5194/bg-9-1237-2012
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发表时间：
2011-10
期刊：
影响因子：
4.9
通讯作者：
Cornelia Mueller-Niggemann;A. Bannert;M. Schloter;E. Lehndorff;L. Schwark
中科院分区：
文献类型：
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作者：
Cornelia Mueller-Niggemann;A. Bannert;M. Schloter;E. Lehndorff;L. Schwark
抽象。为了评价水稻土的内在异质性，对7个稻田进行了5个田间重复的土壤地球化学参数研究（50，100，300，500，700，1000，和2000年的湿地水稻种植），一个淹没水稻苗圃，一个潮汐湿地（TW），和一个淡水网站（FW）从沿海地区在杭州湾，中国浙江省由于土地开垦，所有土壤都是从海洋潮滩基质演变而来的。根据土壤地球化学参数的性质，将其分为两类：一类是表现保守的参数（TC、TOC、TN、TS、磁化率、土壤亮度和颜色参数、δ 13 C、δ 15 N、脂类和正构烷烃），另一类是表现不稳定或快速循环的参数（Nmic、Cmic、硝酸盐、铵、DON和DOC）。利用统计数据分析（描述性、探索性和非参数），通过评价土壤地球化学性质的场地内与场地间空间变异性，对水稻土的宏观异质性进行了评估。结果表明，稻田土壤有机质和矿质组分的内在异质性在田块内小于在研究点间。保守参数的变异系数（CV）值变化在一个较低的范围内（10%至20%），减少从年轻到老水稻土。这表明，随着土壤演变的进展，长期使用的种植地点土壤生物地球化学性质的变异性下降。对于不稳定参数观察到的CV值的一般较高的变化（>20-40%）意味着与更保守的参数相比，在研究这些参数时需要显著更高的采样频率。由于采样策略的代表性可以充分证明，长期的碳积累/封存趋势的调查，在2000年的水稻种植限制下的湿地水稻时序表进行。观测结果不能外推到全球范围，但浙江省填海造地后在海洋潮滩基质上开发的沿海稻田代表了一小部分（
Abstract. In order to assess the intrinsic heterogeneity of paddy soils, a set of biogeochemical soil parameters was investigated in five field replicates of seven paddy fields (50, 100, 300, 500, 700, 1000, and 2000 yr of wetland rice cultivation), one flooded paddy nursery, one tidal wetland (TW), and one freshwater site (FW) from a coastal area at Hangzhou Bay, Zhejiang Province, China. All soils evolved from a marine tidal flat substrate due to land reclamation. The biogeochemical parameters based on their properties were differentiated into (i) a group behaving conservatively (TC, TOC, TN, TS, magnetic susceptibility, soil lightness and colour parameters, δ13C, δ15N, lipids and n-alkanes) and (ii) one encompassing more labile properties or fast cycling components (Nmic, Cmic, nitrate, ammonium, DON and DOC). The macroscale heterogeneity in paddy soils was assessed by evaluating intra- versus inter-site spatial variability of biogeochemical properties using statistical data analysis (descriptive, explorative and non-parametric). Results show that the intrinsic heterogeneity of paddy soil organic and minerogenic components per field is smaller than between study sites. The coefficient of variation (CV) values of conservative parameters varied in a low range (10% to 20%), decreasing from younger towards older paddy soils. This indicates a declining variability of soil biogeochemical properties in longer used cropping sites according to progress in soil evolution. A generally higher variation of CV values (>20–40%) observed for labile parameters implies a need for substantially higher sampling frequency when investigating these as compared to more conservative parameters. Since the representativeness of the sampling strategy could be sufficiently demonstrated, an investigation of long-term carbon accumulation/sequestration trends in topsoils of the 2000 yr paddy chronosequence under wetland rice cultivation restricted was conducted. Observations cannot be extrapolated to global scale but with coastal paddy fields developed on marine tidal flat substrates after land reclamation in the Zhejiang Province represent a small fraction (