论文部分内容阅读
通过将沙棘（ Ｈｉｐｐｏｐｈａｅ ｒｈａｍ ｎｏｉｄｅｓ Ｌ．）与三种杨树品种（小黑杨（ Ｐｏｐ ｕｌｕｓ ‘ Ｘｉａｏｈｅｉ’），昭林 ６ 号杨（ Ｐ．‘ Ｚａｏｌｉｎ０６’）和欧美杨 ６４ 号，（ Ｐ． ｅｕｒａｍ ｅｒｉｃａｎｅ ｃｖ． ‘ Ｎ３０１６’））的人工林分别按株混和行混两种方式进行混交实验，研究了固氮植物沙棘对亚湿润干旱区的杨树人工林养分分布和循环的影响。连续 ３ａ 的观测研究得到以下结果：沙棘叶片的氮、磷和钾的元素浓度显著地高于杨树叶片，混交林中杨树各器官的养分浓度大于纯林中的杨树，但是养分浓度随元素和杨树品种而异；混交林中的土壤的总氮含量和有效氮含量分别比纯林高 ８６％ ～１６４％ 和 １９％ ～３６％ ；混交林中杨树生物量增加不总是与叶片的氮素浓度正相关，但是与氮素年吸收量的增加有关；由于混交林中养分的归还与吸收比率大于纯林，所以杨树混交林中养分的年归还量增加，这意味着杨树与沙棘混交之后有大量的养分进入再循环过程。研究结果表明，沙棘在杨树人工林中作为氮泵起到了维持土壤中稳定的氮素有效性以满足杨树迅速生长的作用。
By comparing Hippophae rhamnoides L. with three poplar species Populus ’Xiaohei’, P. ’Zaolin06’ and P. euram ericane cv. ’N3016’) plantations were mixed by two methods of mixed lines to conduct mixed experiments, the effects of nitrogen fixation plant seabuckthorn on subtropical poplar plantation nutrient distribution and circulation. The observation results of successive 3 years showed the following results: The element concentrations of nitrogen, phosphorus and potassium in seabuckthorn leaves were significantly higher than that of poplar leaves. The nutrient concentrations of poplar organs in mixed forest were higher than those in pure forest. However, Elemental and poplar varieties. The content of total nitrogen and available nitrogen in soil in mixed forest were 86% -164% and 19% -36% higher than pure forest respectively. The increase of poplar biomass in mixed forest was not always related to Nitrogen concentration in leaves was positively correlated, but related to increased annual nitrogen uptake. As the ratio of return and uptake of nutrients in mixed forests was greater than that in pure forests, the annual return of nutrients in poplar mixed forests increased, which means that Yang After the tree and seabuckthorn mixed a lot of nutrients into the recycling process. The results showed that the seabuckthorn played the role of nitrogen pump in poplar plantation to maintain the stability of nitrogen in the soil to meet the rapid growth of poplar.