The investigation area belongs to the „Ecological Experimental Station of Red Soil“, Chinese Academy of Sciences in Yingtan, situated in the Province Jiangxi in China. Studying environmental effects of agricultural management and cropping systems on water resources requires understanding of preferential flow and solute leaching processes that are affected by soil structure dynamics and heterogeneity. For paddy rice fields, the structure of temporarily flooded fine textured soils is dynamically changing due to drainage induced shrinking and tillage induced mechanical (puddling) stresses. Water can move preferentially in continuous macro pores and cracks that bypass the less permeable intra-aggregate pores of the inter-aggregate matrix. The soil structure is depending on the water status, the number of wetting and drying cycles, and the mechanical load history. In paddy rice fields the management affects the dynamics of soil structure, the inter- and intra-aggregate pore systems and also the hydraulic properties due to compaction, cracking, and swelling. The objective of this project is to quantitatively study interrelations between water and crop management practices on soil structure dynamics. The experimental sites are four paddy-fields with a different history of land use (between 20 - >100 years of rice cultivation) and different texture. It will be analyzed if there are differences in soil physical properties because of the different history of the field with an accentuation on aggregation and soil shrinkage and its influencing variables like shear resistance, pore size distribution and rheological properties.