Changes in soil organic carbon in a clay loam soil following ploughing and reseeding of permanent grassland under temperate moist climatic conditions
Changes in soil organic carbon in a clay loam soil following ploughing and reseeding of permanent grassland under temperate moist climatic conditions
复制标题
温带湿润气候条件下永久草地翻耕补种后黏壤土有机碳变化
DOI：
--
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
J. Humphreys
中科院分区：
文献类型：
--
作者：
M. Necpálová;Dejun Li;G. Lanigan;I. Casey;W. Burchill;J. Humphreys
研究了在永久草地（PG）条件下(i)和永久草地改造后（ii）土壤有机碳（SOC）的变化。实验区被划分为四个街区，每个街区有四个围场。在2004年至2011年期间，从每个PG块中提取了5次30厘米深度的复合土壤样本。2008年6月，每个小区一个围场进行了翻耕补种，后四次进行了上述采样。耕后2·5年，改良使土壤有机碳含量降低了32·2 t ha - 1 (P < 0.05)；在头四个月，差异几乎完全消失（86%）。改造对地上生产力、立根和残茬生物量及溶出有机质淋失均无影响。因此，土壤呼吸被认为是修复草地土壤有机碳流失的单一潜在途径。虽然简单的线性回归表明PG有积累土壤有机碳的趋势，但在研究期间，没有证据表明土壤有机碳在改造后恢复到以前的水平。这些结果可能对PG是重要土地利用类型的国家的温室气体清单产生影响。
This study investigated changes in soil organic carbon (SOC) in a poorly drained clay loam soil under (i) permanent grassland (PG) over 7 years and (ii) after PG renovation over 2·5 years. The experimental area was divided into four blocks with four paddocks per block. Composite soil samples from each PG block were taken to 30-cm depth on five occasions between 2004 and 2011. In June 2008, one paddock per block was renovated by ploughing and reseeding and sampled as above on the latter four occasions. Renovation decreased SOC (P < 0·05) by 32·2 t ha−1 in the 2·5 years following ploughing; the difference developed almost entirely (86%) in the first four months. Renovation had no effect on above-ground productivity, standing root and stubble phytomass or on dissolved organic matter leaching. Therefore, soil respiration was considered to be a single potential pathway responsible for the SOC loss from renovated grassland. Although a simple linear regression indicated a tendency for PG to accumulate SOC, there was no evidence of recovery in SOC to previous levels following renovation during the study period. These results could have implications for greenhouse gas inventories in countries where PG is an important land-use type.