白洋淀菹草不同生长期生物量及营养介值变化动态

 本研究在白洋淀王家寨淀区选取５个采样点，分别于菹草返青期、指数生长期、芽殖体发生期和植株衰亡期，对各采样点的菹草植株进行取样、监测并记录各采样点菹草的生物量变化，并对菹草植株各项营养指标含量进行分析。结果表明，菹草指数生长期，生物量增大，粗蛋白、粗脂肪、总磷以及β-胡萝卜素均达到最大值，而粗纤维、粗灰分、钙以及Ｖｃ含量在３－６月的监测中呈现逐渐上升趋势，５月初是白洋淀采集菹草的最佳季节。不同采样点，菹草的营养指标含量存在差异。整个菹草生长期，各采样点菹草粗蛋白含量在１００ｇ／ｋｇ以上，粗纤维含量低于１５５ｇ／ｋｇ，粗脂肪含量在１２ｇ／ｋｇ以上，粗灰分含量在１４０ｇ／ｋｇ以上，钙和磷含量均在３．０ｇ／ｋｇ以上，维生素Ｃ含量在１４０ｍｇ／ｋｇ以上，β-胡萝卜素含量在３１０ｍｇ／ｋｇ以上，营养价值较其他水生饲料高，是草鱼、畜禽理想的青饲料。菹草中的类胡萝卜素等成分可提高蛋品的保健价值，应用前景十分广阔。

Biomass and dynamic changes of nutritive value over different growth periods of Potamogeton crispus in Baiyangdian Lake

Five sites were sampled to analyze the biomass and nutritive value of Potamogeton crispus at the stages of greening,exponential growth,bud emergence and decline.In the exponential growth phase,biomass increased: the contents of crude protein,crude fat,total P and β-carotene were the largest.From March to June,the contents of crude fiber,crude ash,calcium and Vc showed a gradually rising trend.May was the best time for harvesting P.crispus.The nutritive value contents of P.crispus were different at different sampling sites but over the whole growth period of P.crispus at all sampling sites,the contents of crude protein were more than 100 g/kg while those of crude fiber were less than 155 g/kg.The contents of crude fat were more than 12 g/kg and of crude ash were more than 140 g/kg.Ca and total P contents were more than 3.0 g/kg while those of Vc were more than 140 mg/kg,and the contents of β-carotene more than 310 mg/kg.The nutritive values of P.crispus were more than that of other hydrophytic feeds and it was the best feed for fish and domestic animals.The carotene contents of P.crispus could improve health value of eggs and the prospects for applications of P.crispus are very wide.