The Changshu Agro-Ecological Experimental station is located at Changshu, Jiangsu province, China(31.5497N, 120.6984E), and mainly engaged in agriculture, ecological and environmental monitor, research, demonstration and service.This station belongs to the Yangtze River Delta, which is characterized by subtropical humid monsoon climate. The annual mean temperature in this region is 15.5 °C, annual mean rainfall is 1,038 mm, and the frostfree period is 224 days. The main crops are rice in summer and wheat in winter; these crops are planted on annual rotation. The experimental site was planted with wheat in the previous winter and spring. The soil was flooded, plowed, and puddled after the removal of the crop. The soil in the site is classified as Gleyi-Stagnic Anthrosol (CRGCST 2001) developed from lacustrine sediments and has a texture of silt clay. The main properties of the soil at 0- to 15-cm depth are pH (1:1) of 7.35, 2.1 g kg−1 total N, 20.3 g kg−1 organic C, and bulk density of 1.11 g cm−3.