松嫩草原碱茅(Puccinellia tenuiflora)热值和能量动态的研究

Study on calorific value and energy dynamics of Puccinellia tenuiflora in Songnen grassland

碱茅植株热值的季节变化出现 3个峰值 ,并依次降低 ,最大值在 5月初。茎、叶、穗和立枯体热值的季节变化不规则 ,茎和叶最大值均在 5月初 ,最小值茎在 7月初 ,叶在 6月初 ;穗最大值在 7月中旬 ,最小值在 6月初 ;立枯体最大值在 8月初 ,最小值在7月中旬。在整个生长季表现为穗热值 >叶 >茎 >立枯体。碱茅种群地上部能量现存量的季节变化 ,呈单峰曲线 ,峰值出现在 9月初 ,为 6967.75k J/m2。不同季节能量在各器官中的分配比率为 ,5月份为叶 >茎 ;6月份为茎 >叶 ;7月初至中旬为茎 >叶 >穗 >立枯体 ;8月初至 9月初为茎 >叶 >立枯体 >穗 ;9月中旬为立枯体 >叶 >茎 >穗。能量现存量垂直结构 ,地上部为从地表至 2 0 cm高度逐渐增加 ,最大值在 1 0～ 2 0 cm层占地上部能量现存量的 3 6.1 3 % ,然后逐渐下降。地下部的变化规律为随着深度增加能值逐渐减小 ,最大值在 0～ 1 0 cm层占地下部能量现存量的 69.0 1 %。

Seasonal changes of Puccinellia tenuiflora shoot calorific values have three peaks which reduced grogresivdy and the greatest value appeared in early May.The calorific values of stem,leaf,inflorescence and dead standing were irregular in growth season.The greatest values of and leaf appeared in early May,inflorecenc in the middle July and dead standing in early August.The lowest values of stem and inflorecence appeared in early July,leaf in early June,and dead standing in the middle July.In whole growth season,the calorfic values were inflorecence>leaf>stem>dead standing.The seasonal changes of energy standing crop presented single peak curve on the parts of above ground in Puccinellia tenuiflora population and the peak value was 6967.75kJ/m 2 in early September.The distribution ratio of energy were leaf>stem in May;stem>leaf>in June,stem>leaf>inflorescence>dead standing from early to middle in July,stem>leaf> dead standing>inforecence from early in August to early September;dead standing>leaf>stem>inforescence in middle September.The inverse structrue of energy in the parts of above ground was that the enery value gradually increased from surface to 20cm high and the greatest value was in 10～20cm high layer which made up 36.13% of energy standing crop on the parts of above ground,and after that decreasing.In the parts of under ground,the change law of energy value progressively decreased with degree of depth and the greatest value was in 0～10 cm depth layer which made up 69.01% of energy standing crop on the parts of under ground.