Soil macropores play a significant role in soil water retention, water movement and plant growth, influencing regional hydrological and ecological regimes. 

Climatic factors and soil properties may influence distribution patterns of soil macropores on a continental scale. However, it is unclear how climatic factors and soil properties affect the distribution of continental scale macropores. 

Recently, a research team led by Prof. ZHAO Wenzhi from the Northwest Institute of Eco-Environment and Resources of the Chinese Academy of Sciences evaluated the impact of soil properties and climatic factors on soil macropores and explored the effects of soil macropores on eco-hydrological regimes on the continental scale. 

The result was published in Journal of Soils and Sediments on Sept. 21. 

The researchers used spatial error regression model to calculate soil effective porosity (EP) and residual effective porosity (REP) in China, and analyzed the influencing factors of EP and REP. 

Results showed strong spatial variability in EP values, ranging from 0.06 to 0.35 cm³ cm^-3. Higher EP values were found in drylands compared to humid regions. On a continental scale, the better the soil quality, the lower the EP. 

In addition, the formation of soil macropores are correlated with both precipitation and temperature conditions, and the spatial distribution of REP is affected by climatic factors. 

Temperature is a key factor in altering the soil aggregation process, and precipitation is an important factor in inducing changes in soil bulk density and macropores. In humid regions, the contribution of precipitation to macropore development is more significant than that of temperature, while the opposite is true for drylands. 

"This study improves our understanding of the spatial pattern of soil macropores and their eco-hydrological effects at the continental scale," said Prof. ZHAO. 

Contact: 

ZHAO Wenzhi 

E-mail: zhaowzhi@lzb.ac.cn