Through the experiments of returning farmland to wetlands on Wuyur River Wetlands of Heilongjiang Riv-er ,methods & measures for returning farmland to wetlands were preliminarily explored ,and the experiments were analyzed .Result shows that :during that time of natural recovery of enclosure for wetlands in region of returning farmland to wetlands ,the average height of reed patches are 1 .46 m ,and the coverage being 51% ,and the net bio-mass being 326 .24 g ・ m - 2 ;after three years ,the average height of the reed are 2 .02 m ,and the average height in-crease by 27 .7% ;the coverage are 95% ,an average increase of 46 .3% ;net biomass reach 1 480g ・ m - 2 ,an aver-age increase of 78% ;the recovery effect is very significant ;in the three varieties of recovery experiment of sowing the seeds artificially ,the recovery effect of wetland in test area of Echinochloa crusgalli is the most significant ,and the economic benefits are very significant ;followed by test area of Elymus dahuricus ,the worst is test area of As-tragalus adsurgens ;after returning farmland to wetlands ,water quality of wetlands changes significantlyt ;COD of water samples are 24 mg ・ L - 1 before returning farmland ;three years later ,watery COD are 10 .7 mg ・ L - 1 ,am-monia nitrogen content decrease by 0 .5 mg ・ L - 1 ,total phosphorus content decrease by 0 .046 mg ・ L - 1 .% 通过对黑龙江乌裕尔河湿地开展退耕还湿试验，对退耕还湿的方法与措施进行了初步探索，并对试验进行了分析研究。结果表明，通过对退耕还湿区域湿地封育，自然恢复当年，芦苇斑块中芦苇平均高度1．46 m ，盖度达到51％，净生物量为326．24 g ・ m －2，经过3年，芦苇高度平均2．02 m ，平均高度提高27．7％，盖度达95％，平均提高46．3％，净生物量达1480 g ・ m －2，平均提高78％，恢复效果非常明显；人工播撒草籽恢复试验，在试验的3个品种中，谷稗试验区湿地恢复效果最为明显，经济效益十分显著，其次是披碱草试验区，最次是沙打旺试验区；退耕还湿后，湿地水质变化比较明显，退耕前水样 COD 达24 mg ・ L －1，退耕3年后，水样 COD10．7 mg ・ L －1，氨氮含量减少0．5 mg ・ L －1，总磷含量减少0．046 mg ・ L －1。
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