Effects of willow cultivation on chemical and biological properties in coastal saline soil

ABSTRACT The improvement effect of willow (Salix matsudana cv. zhuliu) cultivation on coastal saline soil and the main factors affecting soil properties were studied. Three treatments were designed: willow seeding site (SS), willow afforestation site (AS) and natural control site (CK). The results showed that soil pH and ECe decreased from 8.50 to 7.43 and from 6.8 dS/m to 0.8 dS/m at 0–20 cm layer, respectively. Willow cultivation significantly increased soil organic matter both in SS (3.64 g kg−1 – 4.05 g kg −1) and AS (2.82 g kg−1 – 3.92 g kg −1) treatments. The soil total nitrogen and available potassium of different treatments were increased with time and ranked AS > SS > CK. The AS16 treatment has a higher soil enzyme activity (soil urease, catalase, sucrase and phosphatase) and soil microbial population (bacteria, fungi and actinomycetes). Redundancy analysis suggested that soil pH and salinity were the key factors (85.4%) determining soil microbial quantities. Principal component analysis showed that the soil improvement by willow cultivation was significantly affected by soil enzyme activity, and AS16 had a better effect on costal saline soil especially in reducing soil salinity and improving microbial environment