Effect Of Needle Litter Coverrage On Seed Germination And Seedling Growth On Field

There are mant factors of effect of litter on seed germination and seedling growth. This test is based on practical experience to produce. The study of different pine needles and other conventional mulches covering of Larix olgensis, Pinus koraiensis and Fraxinus mandshurica on seed germination and seedling growth. Experimental field using a random completely design with three blocks, each block of7or9kinds of processing. Pregermination three types of seeds and disinfection the soil had finished before we sowed seeds. Observing the number of seed germination and measuring seedling height everyday, after we sowed seeds. After the emergence number confirmed, seedling height and diameter in each treatment were measured on regular schedule. To measure the impact of mulch on the soil temperature and soil physical and chemical properities in growing season. The results showed that:(1) Soil temperature differences reached a significant level (p<0.05) in different mulches. Soil temperature under the sand coverage is the highest, followed by0.5cm thick larch needles and nursery soil. Only sand and0.5cm thick larch needles can increase soil temperature, the rest of mulches reduce soil temperature. Pine needles can effectively reduce soil temperature; soil temperature under woven straw was significantly lower than nursery soil; soil temperature under sawdust was slightly lower than the nursery soil.(2) The effect of different mulches of larch on seed germination and seedling growth were significantly different. In seed germination stage, sawdust,0.5cm thick larch needles and1.5cm thick mongolian scots pine needles were better than nursery soil; in addition to the sand, the rest of mulches could promote seedling height on early stage; after full stand,1.5cm thick larch needles was the best on seedling height and diameter. The sooner germination of larch seedling had the higher mortality. The thickness of mulches on seed germination was harmful and had little effect on early seedling height. After full stand, it was also negative to growth of seedling height and diameter if thickness is too high or too thin. Compared to three coniferous, mongolian scots pine needles were the best on the early growth; after full stand, larch needles was the best. The needles increased soil acidity and available nutrient, moreover, larch needles was more effective than others.(3) The effect of different mulches of Korean pine on seed germination and seedling growth were significantly different. In the seed germination stage, compared with nursery soil, in addition to the woven straw and5cm thickness larch needles, the rest mulches were better than the nursery soil; in addition to the stand, the rest of mulches promoted seedling height on early stage; after full stand,3cm thickness larch needles was the best on seedling height and diameter. The sooner germination of Korean pine seedling had the lower mortality. The thickness of mulches on seed germination and growth diameter were negative after full stand, however, it was good for early and after full stand growth of seedling height. Compared to three coniferous, larch needles was the best on the early growth.(4) The effect of different mulches of manchurica ash on seed germination and seedling growth were significantly different. In the seed germination stage, compared with nursery soil, in addition to the sand and woven straw, the rest mulches were better than the nursery soil; in addition to the stand, the rest of mulches promoted seedling height on early stage; after full stand, in addition to3cm thickness mongolian scots pine needles, the remaining mulches were better. The sooner germination of manchurica ash seedling had the higher mortality. Compared to three coniferous, mongolian scots pine needles and Korean pine needles were better than larch needles on the early growth; after full stand, larch needles was the best.(5) Covering coniferous promoted three types of seed germination. Sand was the worst in the early height growth. After full stand, the middle thickness of larch needles had the best effect on seedling growth.