| Studying the Polar forests intercropping affects the tree growth and soil fertility before and after forest closing, then analysis the economic benefit.(1)Discussed intercropping impacts the forest growth the Polar forest in Dongting Lake area. When intercropping different crops before closing the average DBH, height and stand volume respectively increased over30.8%,19.6%and91%compared with the contrast. In the3rd year of intercropping Radix Ophiopogonis after closing, the average DBH, heigh and stand volume respectively increased over8%,4.8%and21.3%compared with the contract. The5-year poplar forest’s stand volume increased11.7m3/hm2; when it’s chickens, the increased over6.8%,7.1%and20.6%, and the5-year polar forest’s stand volume increased14.2m3/hm2.(2)Explored after intercropping of cotton, pumpkin and melon1year, before Poplar forest closing in Dongting Lake area, the soil organic content, the whole N and quick-acting P respectively increased over16.4%,19.4%and14.7%compared with the contract. When intercropping locality chicken for2years after the forest closing, the soil organic content increased comparing the forest which didn’t intercropping.(3)Researched the average year profit can reach10488yuan each hectare when intercropping cotton before the forest closing in Dongting Lake area. After closing, it can reach14276yuan when intercropping Radix Ophiopogonis. When it’s chickens, the profit can reach22237.5yuan.(4)Propose the models of intercropping cotton, pumpkin and melon before Poplar forest closing and the models of intercropping Ophiopogonis and locality chicken after closing. |
