宁夏荒漠草原5种乡土植物适应性评价

Adaptability evaluation of several native plants in the desert steppe of Ningxia

开展乡土植物的适应性评价对退化草地生态修复具有重要意义。以宁夏荒漠草原的乡土植物牛枝子(Lespedeza potaninii)、草木樨状黄耆(Astragalus melilotoides)、野生沙芦草(Agropyron mongolicum)、人工繁育沙芦草和新品系沙芦草为研究对象,从农艺性状、光合特性和营养价值3个方面16项指标进行适应性评价。结果表明:牛枝子的生长速度、叶茎比、干草产量显著高于其他4种植物(P<0.05),越冬率达到100%;3种禾本科植物的净光合速率显著高于两种豆科植物(P<0.05),胞间CO_(2)浓度反之;5种植物间气孔导度与蒸腾速率差异不显著(P>0.05);草木樨状黄耆的粗蛋白含量显著高于其他种植物(P<0.05),且中性洗涤纤维、酸性洗涤纤维含量较低,相对饲喂价值高。灰色关联方法综合评价发现,5种乡土植物适应性在等权关联度下呈现草木樨状黄耆>牛枝子>人工繁育沙芦草>野生沙芦草>新品系沙芦草;在加权关联度下呈现草木樨状黄耆>人工繁育沙芦草>牛枝子>野生沙芦草>新品系沙芦草。研究结果表明,草木樨状黄耆与人工繁育沙芦草可作为宁夏及同类地区荒漠草原植被建设中的优先选择。

The evaluation of the adaptability of native plants is important for the ecological restoration of degraded grasslands.The native plants of the Ningxia desert steppe,Lespedeza potaninii,Astragalus melilotoides,Agropyron mongolicum(wild),A.mongolicum(domestication),and A.mongolicum(new),were evaluated for their adaptability in terms of agronomic traits,photosynthetic characteristics,and feeding value in 16 indicators.The results showed that the growth rate,leaf-stem ratio,and hay yield of L.potaninii were significantly higher than those of the other four plants(P<0.05),and the overwintering rate reached 100%.The net photosynthetic rate of three gramineous plants was significantly higher than that of two leguminous plants(P<0.05),and the intercellular CO_(2) concentration showed a converse trend.The differences in stomatal conductivity and transpiration rate among the 5 materials were not significant(P>0.05).The crude protein content of A.melilotoides was significantly higher than the other 4 plants(P<0.05),and the content of neutral detergent fiber and acid detergent fiber was lower,with a high relative feeding value.The comprehensive evaluation by the gray correlation method revealed that the adaptability of the five native plants showed the trend,A.melilotoides>L.potaninii>A.mongolicum(domestication)>A.mongolicum(wild)>A.mongolicum(new)under an equal-weighted correlation,and A.melilotoides>A.mongolicum(domestication)>L.potaninii>A.mongolicum(wild)>A.mongolicum(new)under a weighted correlation.The study concluded that A.melilotoides and A.mongolicum(domestication)can be preferred in the construction of desert steppe vegetation in Ningxia and similar areas.