牧草在NaCl处理土壤中的生长特性及对土壤有效养分的影响

Forage Grass Growth Characteristics in NaCl Treated Soil and It's Effection to Soil Available Nutrients

在填加不同浓度NaCl的潮土上,种植紫花苜蓿、结缕草、小冠花、田菁和早熟禾5种牧草,测定牧草生长和生理指标以及种植后土壤有效养分含量,分析不同牧草在不同NaCl处理土壤上的生长特点及其对土壤有效养分的影响。结果表明,与无盐处理相比,各NaCl处理的结缕草、早熟禾和小冠花的根长、株高、鲜质量均显著降低,田菁亦有降低但差异未达显著水平,紫花苜蓿仅株高在中盐处理以及鲜质量在中盐和重盐处理表现为显著降低,其他差异均不显著;田菁叶片含氮量、叶绿素含量和净光合速率在不同的NaCl处理差异均不显著,紫花苜蓿在重盐处理叶片氮含量显著低于其他处理,其他指标处理间差异均不显著,结缕草、早熟禾和小冠花的相应指标受NaCl处理影响较显著;种植5种牧草对NaCl处理土壤均有一定的影响,其中田菁、小冠花和紫花苜蓿有利于土壤硝态氮含量增加,早熟禾有利于土壤有效磷含量增加,小冠花有利于土壤速效钾含量增加。

Medicago sativa,Zoysia japonica,Coronilla varia,Sesbania cannabina and Poa annua were planted in alluvial soil with different concentrations of NaCl,the growth characteristics of forage plants and soil available nutrients were analyzed.The results showed that,compared with the treatment without NaCl,the root length,plant height and fresh weight of Z.japonica,P.annua,C.varia under each NaCl treatments were significantly reduced.The relative indices of S.cannabina were also decreased but the differences were not significant.For M.Sativa,the plant height in middle salt treatment and fresh weight in both middle and heavy salt treatments showed a significant decrease,but the changes of other indices had no significant differences.The differences of nitrogen content,chlorophyll content and net photosynthetic rate in the leaves of S.cannabina were not significant in different NaCl treatments;the nitrogen content of M.Sativa in heavy salt treatment was significantly lower than that in other treatments,while the differences of other parameters were not significant.The above indices of Z.japonica,P.nnua and C.varia were significantly affected by NaCl treatments.The cultivation of the five forage plants had different influences on the NaCl treated soil,S.cannabin,C.varia and M.sativa facilitated the accumulation of nitrate nitrogen in soil,P.annua had a positive influence on the increase of available phosphorus in soil,and C.varia was beneficial to the increase of available potassium in soil.