Study On The Yield And Quality Of Grass In Winter Fallow Field And Its Influence On Biologic Function To Paddy Fields

The feeding value and yield performance of five forage,including ryegrass,oat,Chinese milk vetch,white clover and cole,planted in winter fallow fields,effect of different forage to weed community structure, and the soil characters of rice paddy after planted were investigated at different regions in Ningxiang,Changsha and Xiangyin since2012to2013. The main results were as follows:1.At Changsha,among the five forage grass,the fresh weight and dry weight of ryegrass was higher than other treatments.Ryegrass fresh grass yield and dry grass yield were38797kg/hm2,4823.3kg/hm2,other treatment followed by oat>milk vetch>rape> white clover,Compared with ryegrass, which fresh weight were reduced by36%、73%、82%、85%、 At Ningxiang,Ryegrass fresh grass yield and dry grass yield were25159.3kg/hm2,4993.1kg/hm2,other treatment followed by oat>rape> milk vetch> white clover,Compared with ryegrass, which fresh weight were reduced by34%、70%、70%、79%。 At Xiangyin,Ryegrass fresh grass yield and dry grass yield were28156.4kg/hm2,3992.5kg/hm2,other treatment followed by oat> milk vetch> rape> white clover,Compared with ryegrass, which fresh weight were reduced by29%、73%、75%、83%。 By measuring forage grass, nutritional quality,the highest average of different forage crude protein content of milk vetch treatment,which were20.4%,20.4%,19.4%at Changsha,Ningxiang and Xiangyin,respectively2. Compared with winter fallow, the weed type and number in winter fallow field was greatly higher than that of other forage grass rotation fields. Compared with winter fallow, the weed species and the total density are4,62.5strains/m2,species decreased by42.9%and density decrease of89.8%at Ningxiang,and the weed species and the total density are8,143.74strains/m2,species decreased by42.9%and density decrease of83.3%at Changsha,and the weed species and the total density are7,122.92strains/m2,species decreased by50%and density decrease of78.6%at Xiangyin.Comparing with different treatment winter crops,the weed type and number in ryegrass fields was smallest.3. Planting forage grass in winter fallow field would improve soil organic carbon content. At Changsha,compared with the CK treatment,soil organic carbon in the ryegrass treatment increased by33.91%,then fallowing oat increased by34.46%,Chinese milk vetch31.79%.At Ningxiang,ryegrass increased21.67%,oat12.41%.At Xiangyin,ryegrass increased12.04%,oat5.76%,respectively.Planting forage grass in winter fallow field would improve soil total nitrogen conten,At Changsha,the soil total nitrogen in the ryegrass(0.63g/kg),Chinese milk vetch(0.72g/kg),white clover (0.72g/kg) and cole (0.73g/kg) treatment all higher the CK(0.58g/kg) treatment.At Ningxiang and Xiangyin,compared with the CK treatment,the soil total nitrogen in the Chinese milk vetch had increased trend.4. Planting forage grass in winter fallow field would improve soil total phosphorus and rapidly available phosphorus content.At Changsha,Ningxiang and Xiangyin,compared with the CK treatment,the soil total phosphorus and rapidly available phosphorus in the ryegrass had increased trend. At Changsha,Ningxiang and Xiangyin,the soil C/N in the ryegrass significantly higher than the CK treatment,Which increased by22.82%,55.96%and11.87%.The soil C/N in the oat also significantly higher than the CK treatment, Which increased by51.41%,34.15%and5.02%。Winter crop increased paddy field ecosystem economic benefit in double rice area in Hunan.Ryegrass had significant advantage to develop feed production.Winter forage grass had development economic worth.In a word,winter fallow paddy field developed winter crop production,improving soil fertility,increasing paddy field ecosystem uniting function.