Correlations between soil physical properties and other parameters related to soil fertility in Songnen Plain, northeastern China

• 1、Key Laboratory of Forest Plant Ecology Ministry of Education, Northeast Forestry University
• 2、College of Life Science,DaQing Normal University

Abstract：This study selected 144 soil profiles, 720 soil samples from different regions of Songnen Plain as the research materials, the aim is to find possible correlation between soil physical properties and other parameters related with soil fertility. 4 soil physical parameters of soil specific surface area, soil specific gravity, soil bulk density and soil porosity were measured, we also measured 12 parameters related with soil fertility and soil physic-chemical properties including soil pH, soil electrical conductance (EC), soil water content, soil organic carbon (SOC), total nitrogen (N), alkali-hydrolyzed nitrogen, total potassium (K), available potassium, total phosphorus (P), available phosphorus, easily extracted Glomalin-Related Soil Protein (EEG) and total Glomalin-Related Soil Protein (TG). Following conclusion were derived from regression analysis: (1) Higher autocorrelation among 4 physical parameters were observed, for example, strongest positive correlation was observed between soil specific gravity and soil porosity (R2=0.64,slope=20.15). The strongest negative correlation was between soil bulk density and soil porosity(R2=0.25，slope=- 37.7). (2) Soil specific surface area was positively correlated with 9 out of the 15 parameters, and the strongest positive correlation was observed in soil water content(R2=0.24，slope=0.08). The strongest negative correlation was observed between soil specific surface area and soil pH(R2=0.12，slope=- 0.008). (3) Soil specific gravity was positively correlated with 2 out of the 15 parameters(p<0.05). There was non-correlations between the other 13 parameters and soil specific gravity. (4) Soil bulk density was negatively correlated with 11 out of the 15 parameters(p<0.05). The most significant positive correlation was found between soil bulk density and potassium (R2=0.04，slope=25.91) (p<0.05). (5) 9 of the 15 soil parameters were positively correlated with soil porosity (p<0.05), while others did not or negatively correlated with soil porosity. The significant correlations found in present paper indicates that soil physical properties are important in regulating soil fertility and soil physic-chemical properties, and soil physical properties tested in present paper (soil bulk density, soil porosity and soil specific surface area) should be highlighted in the study of soil degradation in Songnen Plain in the future.?????

Keywords： soil physical properties soil physic-chemical parameters soil fertility parameters regression analysis?????