| The researches were carried out by simulating experiments and field experiments as well as investigation and many sampling analyse to examine the effects of sulphate in groundwater on soil sulphur nutrition and crop qualities and yields. In order to understand the contribution degree of groundwater sulphate to soil sulphur nutrition and crop nutrition, ryegrass and rapeseed and wheat were chose as the specifically crop to give out theoretical reference to regulate sulphur fertilizer resource and cut down the disadvantage of sulphur fertilizer effect on entironment. The main results were presented as follows:1 .Investigation on groundwater table in the region of Huaibei plain, plain along Yangzi River and Jianghuai hill in 2001'-2002' revealed that the groundwater table of Anhui varied from 0.35 meter to 16.5meter. In Huaibei plain the groundwater table ranged from 0.43 meter to 11.6 meter, averaged at 3.01 meter and about 52.63% of the total was below the averaged level. At the same time, the water level have a decline trend from the north to the south. While in Jianghuai hill it changed from 0.65 meter to 16.5 meter, the mean was 4.01 meter, 70% of the total were under the level. And in plain along Yangzi River the ground water's level range was from 0.35 meter to 15.5 meter, the mean was 2.89 meter, and 66.67% of all were varied below 2.89 meter.2. The survey of concentration of sulphate in groundwater from 2001' to 2002' showed that sulphate in groundwater have a large scope in Anhui ranging from 1.4 mg/L to 117.65 mg/L, the average was 20.91 mg/L. In Huaibei plain the sulphate content of groundwater ranged from 2.15 mg/L to 56.1 mg/L, and the average was 12.95 mg/L. While in Jianghuai hill it changed from 4.8 mg/L to 117.65 mg/L, the average was 35.52 mg/L. And in plain along Yangzi River the concentration of sulphate in groundwater range was from 6.68 mg/L to 85.65 mg/L, the average was 26.33 mg/L. And the distribution of sulphate in groundwater has distinct geography polarization. Of the tested groundwater samples, in Huaibei plain 95.24% had a sulphate content below 30 mg/kg, among these 52.38% were under 10 mg/kg and 28.57% were varied from 10 mg/kg to 20 mg/kg and the remain 14.29% were ranged from 20 mg/kg to 30 mg/kg. While in Jianghuai hill and plain along Yangzi River the distribution of sulphate in groundwater had a lager extent, include 18.60% and 30.24% had a sulphate concentration below 10 mg/kg and varied from 10 mg/kg to 20 mg/kg, another 18.60% and 13.96% and 18.60% had a sulphate content from 20 mg/kg to 30 mg/kg and 30 mg/kg to 50 mg/kg and exceed 50 mg/kg, respectively.3.The groundwater table fluctuated along with month variety. A 12 months' fixedin8. Results from two field experiments indicated that the effect of S fertilizer were related with the groundwater table, which determined the significant difference among the treatments. In the field where the groundwater level was lower, S application can increased rapeseed yield and promoted growth of rapeseed, increased plant height, leaves area, green leaves, branches, available pods per plant and available seeds per pod. But too much S fertilizer application decreased rapeseeds yield. Applying S fertilizer increased plant uptake of S and N, and increased the seeds oil content and glucosinolate, but decreased the protein content contrarily. The same results could be found from the wheat field experiments, when the groundwater level was low the S application could promote plant height and available grains per spike significantly. And during the three growth periods the uptake of S and N of every plant organ were increased according to S application. Applying S fertilizer also increased protein content and amino acid content in wheat grains, among amino acid the Aspartate Threonine, Valine. Isoleucine. Tyrosine. Phenylalanine and Proline were increased 10 percent over control.9. In the field where the groundwater level was lower, rapeseed were proned to affect rape sclerotiniose , S application promoted the im...
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