| To aim to improve the hypogenesis of alfalfa resulted from single farming structure, low productivity and water resource deficiency, based on the generation of experiences and lessons of production practice in the past years, further research was conducted to investigate the effect of differences mulch and ridge integrated skills on the development and products of alfalfa, the effects of differences mulch and ridge on the rate of emergence, soil water storage and hay product.The research adopted mulch and ridge integrated skills to grow alfalfa, furrows as planting areas, ridges as water-harvesting areas, experimental area was arranged at random, nine treatments(4 furrows and ridges ratio×2 mulched ridges pattern + 1 control), three replicate, where 4 furrows and ridges ratio(1:0.5,1: 0.75,1: 1和1: 1.25, that meant furrows and ridges ratios were 60:30,60:45,60:60 and 60:75 respectively, unit mm), mulched ridges pattern were plastic mulched and soil bared ridges, the width and thickness of the plastic film of plastic mulched ridge were 1.2 m and 0.08 mm respectively, the plastic mulch edges were compressed with soil in case of wind damage, which the soil bared ridges were original soil rammed. The seeds were sowed in the furrows, and then were mulched with straw of 6600~6750 kg.hm-2, when the rate of seedling emergence was 70%, the straw was removed. The height of water-harvesting ridges was 20cm, the top of which was arc; ridge surface and ground were angled. 45 degree, the width of ridges were 6m, every plots had four ridges and three furrows.The results as shown follows:1. The average rate of seedling emergence and rate of seedling establishment were increased and at the same time the days of seedling emergence and seedling storage were decreased by the mulched ridge treatment. The average rate of seedling emergence and rate of seedling establishment in the mulched ridge treatment were 82.7% and 70.81 respectively; the average rate of seedling emergence and rate of seedling establishment in the bared ridge treatment were 82.7% and 70.81% respectively. The rates of seedling emergence were ordered as MR60 > MR75> MR45 > CK > SR75 > MR30> SR60 >SR45 > SR30,while the highest of them was MR60, which were 90.37%a and 78.33%a respectively. 2. The mulched ridge treatment increased the hay product per area as well as the synthesis of crude protein and absorption of total P. The wider mulched ridge treatment (furrow width: ridge width=75:60 and furrow width: ridge width=60:60) increased product more than the narrower mulched ridge treatment (furrow width: ridge width=45:60 and furrow width: ridge width=30:60), the sequence of hay product is MR60 > MR75 > MR45 > MR30 > SR60 > SR75 > SR45 > SR30. The highest of them was MR60, and its total calcium content,total P content,acid fiber,crude fat and crude protein were 1.521%,0.571%,11.294%,2.973% and 27.413% respectively.3. The cultivation of mulch and ridge integrated cultivation had an especial effect on the water-harvesting of 0-120cm soil layer. The mulched ridge treatment has a significant effect on the water-harvesting,the reduction of soil water transpiration area and the improvement of water supply. On the contrary, the bared ridge treatment had not showed significant effect. The average soil water storage of MR75 during the first-cut alfalfa growing period was higher than CK by 25.08mm, while during the second-cut alfalfa growing period was higher than CK by 24. 84mm.4. Among the cultivation of mulch and ridge integrated cultivation, the mulched ridge treatment had a significant effect on the increase of soil effective nutrition, especially the available N in the 0~20cm soil layer; inhibited the reduction of soil organic carbon, reduced the decreasing rate of available soil P, increased surface water as well as water use efficiency, while MR60 showed the highest water use efficiency. The total P and N and soil organic matter was increased and the available ingredients were reduced in the MR60 treatment.In conclusion, compared mulched ridge treatment with conventional cultivation in a flat land, compared mulched ridge treatment with and bared ridge treatment, specially the MR60 and MR 75, increased the soil surface temperature, water use efficiency, soil nutrition content, especially the soil N and SOC content, improve the field ecology environment of alfalfa, to realize the purpose of increase the alfalfa product and farmers income, in addition, to provide technologic support to the conversion cultivated land to grass and ecologic construction strategy.
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