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The shortage of freshwater resources is one of the main inhibitors in development of sustainable agriculture. Traditional rice cultivated in waterlogged conditions consumes a large of freshwater, about 80% of agricultural water, which exacerbates the pressure of freshwater resources. So, the research and generalizing of rice water-saving cultivation are important in china. At present, rice cultivated with plastic film mulching and rice straw mulching in aerobic soil are the most common models, and achieve considerable results in country or overseas. In our study, a field experiment was conducted to study the effect of rice cultivated model on plant biological traits, soil productivity characteristics, mineral nitrogen dynamic changes, nitrogen use efficiency differences, soil microflora, soil microbial biomass carbon and nitrogen, chlorophyll content and exudation volume. The objective of the present study is to clarify the mechanism of soil nitrogen supply and growth of crops under different rice cultivated model, and solve low nitrogen use efficiency problem, so that we can provide a theoretical basis for rice cultivated model in aerobic soil condition.A field experiment was carried out in Farm of Yancheng Academy of Agriculture Science, Jiangsu province. In rice season, there were a waterlogged soil treatment (SZ) and three aerobic soil treatments, including the ground covered with plastic film mulching (FM), with rice straw mulching (GC) and without any mulching (LL). After rice cultivation barley was planted in same year with nothing mulching in all treatments. Accordingly, the post-barley treatments was marked as post-waterlogged soil treatment (PSZ), post-plastic film mulching treatment (PFM), post-rice straw mulching treatment (PGC) and post-no mulch treatment (PLL), respectively. The results from the experiment as follows:The field experiment showed that the yield of aerobic rice was higher than waterlogged rice. The yield of GC was maximum in 4 treatments, FM and LL were 10.4%, 8.7% higher than SZ, respectively. The rice cultivated in aerobic soil was profit to post-barley yields, whose increase degree of yields was 2.8%-25%. Thereinto, the increase degree of yield in PGC was maximum in 4 treatments. The biomass of aerobic rice was 4.4% higher than waterlogged rice in average, the biomass of FM and GC were 6.6%, 13.3% higher than SZ, respectively. The biomass of PGC was maximum (24554 kg·hm-2), which was 3424,6059.6961·kg·hm-2 higher than PFM, PLL and PSZ, respectively. The aerobic rice without fertilization couldn’t increase soil productivity, but fertilization could increase soil productivity distinctly. Compared with SZ, GC increased soil productivity distinctly (29.0%); FM increased soil productivity slightly (14.7%); but LL decreased soil productivity distinctly.Only GC accumulated nitrogen more than SZ in rice season, GC was 4.12%,12.19% and 22.24% higher than SZ, FM, LL, respectively. In barley season, PGC, PFM and PLL all accumulated nitrogen more than PSZ. As a whole, aerobic treatments were profit to accumulate nitrogen and GC was the best in rice-barley systems. No matter rice cultivated in aerobic soil or waterlogged soil, NH4+-N and NO3--N were main nitrogen nutrition. The differences were that rice cultivated in waterlogged absorbed NH4+-N more than NO3--N, rice cultivated in aerobic soil absorbed NO3--N more than NH4+-N. In addition, no matter NH4+-N or NO3--N, post-barley treatments (PGC, PFM, PLL) absorbed NH4+-N and NO3--N higher than PSZ. In 3 aerobic treatments, PGC absorbed NH4+-N and NO3--N higher than PFM and PLL.The NAUE of rice cultivated in aerobic soil was higher than SZ, and the differences were significant. The differences of NPE between rice cultivated in aerobic soil and SZ were slight. The NAUE of post-barley showed that, PGC was maximum in 4 treatments, and which was 0.88,2.19 and 7.97 kg·kg-1 higher than PFM, PLL, PSZ, respectively. The NPE was the same to the NAUE, PGC was 2.79,6.97 and 13.34 kg·kg-1 higher than PFM, PLL, PSZ, respectively. Comparing barley with rice, the NAUE and NPE in rice were lower than in barley. The NAUE in rice was 12.46 kg·kg-1 lower than in barley, the NPE in rice was 10.58 kg·kg-1 lower than in barley.The results obtained were showed that soil microflora and microbial biomass C, N increased significantly in rice and post-barley seasons when pre-rice cultivated in aerobic soil, GC treatment increased more significantly than FM and LL. In rice season, the microflora of FM, GC, LL were 1.61,1.9 and 1.49 times to SZ. In barley season, the microflora of PFM, PGC, PLL were 1.21,1.85 and 0.96 times to PSZ. In rice season, the microbial biomass C of GC was maximum, LL was minimum, GC was 14.2%,30.0% higher than FM, LL, respectively, but no significant differences between them. In addition, the microbial biomass N of GC was maximum, LL was minimum, GC was 27.8%,52.3% higher than FM, LL, respectively. In barley season, the microbial biomass C of PGC was maximum, PLL was minimum, PGC was 19.94%,25.56% higher than PFM, PLL, respectively. In addition, the microbial biomass N of PGC was maximum, PLL was minimum, PGC was 16.95%,25.35% higher than PFM, PLL, respectively. In conclusion, rice cultivated with straw mulching in aerobic soil was profit to increase soil microflora and microbial biomass C, N significantly.The content of water and nitrogen were main factors in effect of exudation volume of rice. When the content of nitrogen fertilizer was same, water was chiefly factor in effect of exudation volume. In entire rice growth season, the exudation volume of rice cultivated in waterlogged was higher than rice cultivated in aerobic soil. In aerobic treatments, the exudation volume of GC was maximum, LL was minimum, which indicated that rice cultivated with straw mulching in aerobic soil could preserve water evaporating and enhance root vim. The same to exudation volume, the content of water and nitrogen were main factors in effect of chlorophyll content. When water and nitrogen were enough, leaves chlorophyll content was high and the photosynthesis was good to make photosynthesis production, accordingly, the yield was high. As a whole, in rice front and metaphase growth season, leaves chlorophyll content of aerobic treatments was higher than SZ. In anaphase growth, the leaves chlorophyll content of aerobic treatments decreased significantly, which was 0.14 mg/g lower than SZ, and indicated that the leaves chlorophyll content of aerobic treatments decompounded quickly and water shortage affected chlorophyll content compounding.In short, rice cultivated with straw mulching in aerobic condition could change the form and content of soil nitrogen, increase microbial flora and soil microbial biomass content, improve soil fertility, raise crop production and nitrogen use efficiency. Therefore, this model hand great value to be extended.
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