Wavelet analysis of the correlations between soil properties and potential nitrous oxide emission at farm and landscape scales
Wavelet analysis of the correlations between soil properties and potential nitrous oxide emission at farm and landscape scales
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DOI：
10.1111/j.1365-2389.2011.01361.x
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发表时间：
2011-06-01
影响因子：
4.2
通讯作者：
Lark, R. M.
中科院分区：
文献类型：
--
作者：
Milne, A. E.;Haskard, K. A.;Lark, R. M.
我们分析了一氧化二氮的排放率和其他一些性质的土壤芯收集在一个7.5公里的横断面在英格兰东部的对比土地利用和母质。这一比例尺样带的变化进行了比较，在同一地区的农场内的空间尺度在以前的研究中所作的一组可比的测量。利用小波变换分析了农田到景观尺度土壤性质与排放速率相关性的尺度依赖性和空间一致性。分析揭示了规模依赖的复杂模式。土壤有机碳与排放率仅在田间尺度上相关。有一个显着的相关性排放率和特定的功能的充水孔隙空间，只看到在景观尺度。排放率与土壤硝态氮含量在中间和coarseum尺度（显着，虽然弱，在最好的领域内的尺度），并与pH值在中间尺度。小波分析表明，这些相关性在空间上是不均匀的。硝酸盐浓度和排放率之间的相关性在最好的景观尺度（约60和120米之间）是不显着的北方部分的样带主要对应于土壤在较低的绿砂，但这些变量显着相关，在这个尺度上的其他母质。这些发现对土壤中一氧化二氮排放的建模和库存具有影响。他们指出，在景观尺度上，硝酸盐含量和充满水的孔隙空间是预测一氧化二氮排放量的关键土壤特性，因此应纳入清单计算的过程模型和排放系数。
We analysed data on nitrous oxide emission rate and some other properties of soil cores collected on a 7.5-km transect across contrasting land uses and parent materials in eastern England. The variation on this landscape-scale transect was compared with that of a comparable set of measurements made in a previous study on within-farm spatial scales in the same region. We used the wavelet transform to analyse the scale dependence and spatial uniformity of the correlations between soil properties and emission rates from farm to landscape scale. The analysis revealed a complex pattern of scale dependence. Soil organic carbon was correlated with emission rates at within-field scales only. There was a pronounced correlation between emission rates and a process-specific function of the water-filled pore space, seen only at landscape scales. Emission rates were strongly correlated with soil nitrate content at intermediate and coarsest scales (and significantly, although weakly, at the finest within-field scales), and with pH at the intermediate scales. The wavelet analysis showed that these correlations were not spatially uniform. The correlation between nitrate concentration and emission rates at the finest landscape scale (between approximately 60 and 120 m) was not significant in the northern part of the transect corresponding primarily to soils over the Lower Greensand, but these variables were significantly correlated at this scale over other parent materials. These findings have implications for modelling and inventory of nitrous oxide emissions from soil. They indicate that, at the landscape scale, nitrate content and water-filled pore space are key soil properties for predicting nitrous oxide emissions and should therefore be incorporated into process models and emission factors for inventory calculations.