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1.
松嫩草原拂子茅种群热值、生物量和能量动态的研究   总被引:7,自引:0,他引:7  
拂子茅(Calamagrostis epigejos)全株的叶的热值和季节变化规律相似,呈双峰曲线,2个峰值分别出现在6月中旬和8月初,茎热值的变化呈单峰曲线,峰值出现在8月初,穗笔立枯体的热值变化呈波动型,穗的最大值出现在9月初,立枯估出现在6月中旬,地上部能量现状量的季节变化与生物量变化同步,呈单峰曲线,不同季节能量在各器官中分配比率为:6月中旬为叶>茎>穗,7月初为叶>茎>立枯体>穗,7月中旬为叶>茎>穗>立枯体,8月至9月为叶>茎>立枯体>穗,能量的垂直分配,地上部为从地表至20cm高度逐渐增加,最大值在10-20cm层占地上部总能量的26.91%,然后逐渐下降,地下部能量垂直分布规律是随着深度增加而逐渐减少,能量集中分布在地下0-10cm层在占地下部总能量69.01%。  相似文献   

2.
东北草原盐碱植物虎尾草的热值和能量分配特征的研究   总被引:8,自引:0,他引:8  
虎尾草全株、茎和叶的热值的季节变化规律相似,从7月初至8月初出现2个峰值,然后呈逐渐下降趋势.穗的热值变化呈U字型,2个峰值分别出现在8月初和9月中旬.立枯体热值变化不规则,最大在8月初.虎尾草种群地上部能量的季节动态呈双峰曲线,峰值分别出现在8月初和9月初,最大值在9月初为7381.27kJ  相似文献   

3.
松嫩平原羊草草甸草原主要植物种群能量积累和分配   总被引:7,自引:2,他引:5  
在松嫩平原羊草草甸草原,羊草、拂子茅、碱茅和虎尾草各器官热值的季节变化呈波动型,但总的规律是穗>叶>茎>立枯体.4种植物种群地上部能量现存量的季节变化均呈单峰曲线,能量积累量为羊草>拂子茅>虎尾草>碱茅.能量增长率一般呈双峰曲线,第一次峰值出现在抽穗期,第二次在种子成熟期,生长末期出现负值.地上部能量的水平分布规律,不同生育期在各器官中的分配比率不同.4种植物种群能量的垂直分布规律相似,即地上部能量的垂直空间分配格局基本上呈塔形,最大值出现在10-30cm空间内.地下部能量垂直结构由地表至土壤深层呈典型的倒塔形,最大值在0-10cm层.地下部的能量现存量约为地上部的3-4倍。  相似文献   

4.
小叶章草地生态系统结构与功能的研究Ⅳ能量的固定和分配   总被引:11,自引:0,他引:11  
马克平 《生态学报》1995,15(1):23-31
小叶章草在生态系统年净初级生产力为30579。17kJ/m^2.a,其中地上净初级生产力占37.64%,地下净初级生产力占62.36%。不同植物器官(组分)的能量现存量差异很大,上部根占植物亚系统总能量现存量的54.87%,穗的能量现存量仅占0.03%,其它器官的能量现存量从大到小依次为:茎>叶>根茎>枯落物>下部根茎>死根。不同植物器官(组分)热值含量水平亦存在较大差异,以去灰分热值比较,由大到  相似文献   

5.
松嫩草原碱茅群落环境因素与凋落物分解季节动态   总被引:10,自引:2,他引:8  
对碱茅群落凋落物分解季节动态与微生物呼吸速率、土壤有机质、土壤C/N、土壤温度、土壤水分等11种环境因素的季节动态进行了研究,结果表明,凋落物分解季节动态呈单峰曲线,8月中旬达最大值8.109mg.g^-1.d^-1,凋落物分解指数为1.93,95%凋落物分解约需4a;微生物呼吸速率季节动态呈单峰曲线,7月中旬达最大值,为11.4g.C.m^-2.d^-1;凋落物分解速率同土壤有机含量、土壤C/N显著负相关;凋落物分解速率同土壤温度显著正相关。  相似文献   

6.
 本文在生物生产力研究的基础之上,通过热值测定,对东北东部帽儿山地区21年生人工落叶松(Larix gmelinii)生态系统净初级生产力形成过程中的能量特征做了系统研究。结果表明:(1)植物热值随植物种类、器官、分布层次、年龄及季节而发生变化。(2)生态系统中活植物体的能量现存量为269.719×1010J/ha,而枯死体中的能量现存量为36.817×1010J/ha,其中凋落物层和立枯体中能量贮量各占84.04%和15.96%。 (3)生态系统能量净固定量为264.346×109J/ha·yr,其中29.49%的能量存留在植物体中,用于植物净生长。生态系统年能量归还量为88.809×109J/ha,其中32.39%的能量在当年被分解释放,余下能量积累于凋落物层之中;生态系统的能量转化效率为2.299%,与其它森林植物群落相比,落叶松人工林系统是高效率的能量代谢系统。  相似文献   

7.
 本文在生物生产力研究的基础之上,通过热值测定,对东北东部帽儿山地区21年生人工落叶松(Larix gmelinii)生态系统净初级生产力形成过程中的能量特征做了系统研究。结果表明:(1)植物热值随植物种类、器官、分布层次、年龄及季节而发生变化。(2)生态系统中活植物体的能量现存量为269.719×1010J/ha,而枯死体中的能量现存量为36.817×1010J/ha,其中凋落物层和立枯体中能量贮量各占84.04%和15.96%。 (3)生态系统能量净固定量为264.346×109J/ha·yr,其中29.49%的能量存留在植物体中,用于植物净生长。生态系统年能量归还量为88.809×109J/ha,其中32.39%的能量在当年被分解释放,余下能量积累于凋落物层之中;生态系统的能量转化效率为2.299%,与其它森林植物群落相比,落叶松人工林系统是高效率的能量代谢系统。  相似文献   

8.
松嫩草原优势植物羊草立枯体分解的研究   总被引:7,自引:2,他引:5  
在羊草草原上当年羊草的枯死体大部分以立枯体的形态存在,立枯量约占枯死量的75.34%。立枯体与凋落物的分解速率的季节变化趋势基本相同,均呈抛物线型。每月凋落物的分解速率均大于立枯体分解速率,二者最小值均出现在10月份。其中立枯体分解速率最大值出现在7月,凋落物出现在8月。立枯体和凋落物损失率的季节变化曲线均呈指数形式,立枯体的所损失量约占凋落物损失量的77.11%。立枯体的分解与水热因子均呈指数正  相似文献   

9.
内蒙古典型草原的生物量与生产力   总被引:7,自引:0,他引:7  
草原地上生物量是由植物的绿色部分(活植物体)、立枯体(未脱离母体的枯枝叶)和凋落物(落到地面上的枯枝叶)三部分组成,生物量是随季节、气温、雨量而变动,以8月份最高,4月初和9月底最低。生物量中的绿色量和立枯量在季节动态中的消长关系明显相反。立枯物在旱象较明显的6月中旬出现后,随着群落生物量达到高峰后,气温降低,绿色体大量枯萎,立枯量急剧增加,到9月上中旬立枯量与绿色量持平。随后,立枯量迅速超过绿色量,到10月中旬,绿色体完  相似文献   

10.
羊草种群能量生殖分配的研究   总被引:22,自引:4,他引:18  
对羊草种群能量生殖分配规律研究表明,在羊草种群中,各构件热值的大小顺序为穗〉营养枝叶鞘〉生殖枝叶鞘〉营养枝叶〉营养枝茎〉生殖枝茎〉生殖枝叶〉凋落物;营养生长和生殖生长的能量分配比例的大小顺序为营养枝〉根茎〉凋落物〉生殖枝;各构件能量分配比例的季节动态也有差异,在羊草种群的生殖枝构件中,茎和叶鞘的分配比例较大,而穗和叶的能量分配比例较小。  相似文献   

11.
There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak curve which appeared in the early August. The calorific values in inflorescence and dead standing showed a fluctuation and the peak value of inflorescence was in the early September and that of dead standing was in middle June. The seasonal changes of energy standing crop on the above-ground part synchronized with that of the biomass, which presented a single peak curve. The energy allocated to each organ in different seasons was in the order as leaves >stem >inflorescence in middle June, leaves >stem >dead standing >inflorescence in early July, leaves >stem >inflorescence >dead standing in middle July, and leaves >stem >dead standing >inflorescence from August to September. The vertical allocation of energy in the parts of above-ground was that the energy value gradually increased from the surface to the 20 cm high level and the maximum value at the 10-20 cm high level which made up 26.91% of energy on the above-ground partion, and then it was decreased. In the under-ground portion, the energy value progressively decreased with depth and the maximum value was at 0-10 cm depth layer which made up 69.01% of energy of the under-ground portion.  相似文献   

12.
不同种源黄花蒿生长及生物量分配   总被引:1,自引:0,他引:1  
对都安、崇左、阳朔和融安县四个不同种源黄花蒿的生长发育状况和生物量分配进行比较,结果表明:黄花蒿的生长旺盛期是在5月底至7月初,6月中旬为生长的高峰期,这段时期内应施以重肥;不同种源黄花蒿各功能构件生物量平均值具有相同的规律:茎构件>叶构件>根构件;都安种源的叶构件生物量和青蒿素含量均比其它种源的高,综合表现最优,是引种栽培的好种源。  相似文献   

13.
Benthic foraminiferal assemblages in subrecent deposits are commonly used to reconstruct past sea level. Interpretations are generally made by comparison with either modern dead or total (live plus dead) assemblages. In both cases there will have been post-mortem changes that have differentially affected preservation. It is therefore important to establish the primary ecological controls by analysis of the living assemblages. We have determined the spatial and temporal variability of intertidal benthic foraminifera in the surface (0–1 cm) sediments from a time series survey of 31 sampling stations at Cowpen Marsh, for a period of 12 months. We counted 112,067 live foraminifera assigned to 28 species. The fauna was dominated by two agglutinated species (Jadammina macrescens and Trochammina inflata) on the high and middle marshes, and three calcareous species (Elphidium williamsoni, Haynesina germanica and Quinqueloculina spp.) on the low marsh and tidal flat.The standing crop of the whole intertidal zone, including the high, middle, low marsh and tidal flat habitats, and the individual species varied both temporally and spatially. The standing crop of the intertidal zone as a whole was greatest in the summer months and showed a positive correlation with elevation. The standing crops of the high and middle marshes showed similar temporal variation with peaks in summer and autumn and a trough in winter. The low marsh showed numerous peaks and troughs of standing crop during the year, whereas the tidal flat showed a single peak in summer. The standing crops of Jadammina macrescens and Trochammina inflata on the high and middle marshes peaked from April to May and August to October with troughs in winter. These agglutinated species showed a strong correlation with elevation. Haynesina germanica peaked in May to August and November to January on the low marsh, whereas on the tidal flat there was a single peak in July. The standing crops of E. williamsoni on the low marsh and tidal flat were relatively high in June and May, and July, respectively. Quinqueloculina spp. peaked in May to July on the low marsh and July on the tidal flat. The species was also found in the middle marsh from July to May and high marsh from September to November. Haynesina germanica showed a strong negative correlation with elevation, whereas the other two dominant calcareous species demonstrated weak negative correlations with both elevation and salinity.Reconstructing former sea level depends primarily on the recognition of high and middle marsh assemblages and in this study these are shown to be strongly controlled by elevation rather than salinity. Caution may be needed in interpreting low marsh and tidal flat data as salinity plays a more important role here.  相似文献   

14.
 本文报告了甘肃天祝高寒珠芽蓼(Polygonum viviparum)草甸群落地上及地下四部分生物量的热值和营养成分动态,并对其放牧利用的价值进行了总的评价。 6—9月现存量的热值平均为18330焦/克干物质,或20279焦/克去灰分物质,较立枯物+凋落物、活根、死根的平均值为大;死根略大于活根。在珠芽蓼及其他大多数植物种子成熟期的8月下旬,现存量的热值最大,其他三部分的热值变化也有其各自的特点。现存量6—9月的平均营养成分以绝对干重计为:粗蛋白13.52%,粗脂肪2.25,粗纤维22.99,无氮浸出物51.88,粗灰分9.61(其中钙1.627,磷0.164);在时间变化上四部分各有其特点。根据地形、植物组成、产量、易食性、适口性、热值和营养成分等综合条件,认为珠芽蓼草甸是良好的放牧地。  相似文献   

15.
Air-dried fresh and dead specimens ofPolygonum cuspidatum were incubated for 250 days in the laboratory, and the growth and turnover of microbial biomass-C in the organic matter were studied. The biomass-C in the fresh leaf and fresh stem attained maximum levels on day 14 and day 7, respectively, and then settled down to stable levels. In the dead leaf and dead stem, increase in biomass-C ceased by day 4 and the biomass-C levels did not change thereafter. The turnover time of the biomass-C was estimated from the amount of biomass-C and the release rate of CO2-C. The turnover was rapid in the early period of incubation. Then the turnover time became longer and after incubation for 70 days the values approached those in natural soils (longer than 16 days). During the incubation period, nitrogen was not mineralized in any organic matter. In the dead leaf and dead stem, asymbiotic nitrogen fixation activity increased after incubation for about 40 days and disappeared by the end of the incubation period, whereas nitrogen fixation was hardly detected in the fresh leaf and fresh stem.  相似文献   

16.
厚穗宾草地上部生物量与株高的分形关系   总被引:1,自引:0,他引:1  
应用分形几何学的方法对厚穗宾草种群地上部生物量与株高的关系进行了分析研究.结果表明:厚穗宾草种群地上部生物量与株高之间存在着明显的分形关系.不同时期,不同高度的植株在空间分布结构存在着相似性,各时期分维数分别为1.993 1(3月),1.317 3(5月),1.618 2(6月),2.119 1(7月),1.935 6(8月),1.668 6(9月).整个生长季,分维数呈抛物线型,7月份达到最大值,并且生长后期的较大植株同生长前期的植株相似,分维数为1.466 8.  相似文献   

17.
在盆栽条件下,对不同荷花(Nelumbo nucifera Gaertn.)品种〔藕莲品种'大紫红'('Dazihong')、花莲品种'中国红·上海'('Zhongguohongshanghai')和花藕兼用莲品种'逸仙莲'('Yixianlian')〕出泥部分(叶和花)和泥下部分(根状茎)的生长性状和部分生理指标进行了比较研究,并对3个荷花品种出泥部分与根状茎间的生长性状和部分生理指标进行了相关性分析.结果表明:'大紫红'在整个生长发育期不开花;'中国红·上海'开花时间相对较早(6月上旬),花重瓣且色泽鲜艳;'逸仙莲'开花时间相对较晚(7月上中旬),花单瓣呈白色.3个荷花品种中,'大紫红'立叶数最少,立叶面积最大,根状茎膨大明显,根状茎中可溶性糖和可溶性蛋白质含量最高;'中国红·上海'立叶数最多,立叶中叶绿素含量最高,根状茎节间长度最长,但根状茎膨大不明显;'逸仙莲'立叶数居中,叶柄最长,根状茎膨大明显,根状茎中可溶性蛋白质、可溶性糖、淀粉和维生素C含量介于其他2个荷花品种之间.相关性分析结果表明:荷花立叶面积与根状茎节间长度呈显著负相关,而与根状茎中可溶性糖、可溶性蛋白质及维生素C含量呈极显著或显著正相关;叶柄长度与根状茎直径和根状茎节间质量呈显著正相关;立叶中叶绿素含量与根状茎节间长度和根状茎中淀粉含量呈显著正相关,而与根状茎中可溶性糖含量呈显著负相关.研究结果显示:根据供试3个荷花品种的立叶面积、叶柄长度、立叶中叶绿素含量可间接判断根状茎的生长发育及营养品质状况,并可进一步应用于快速选育花藕兼用莲品种.  相似文献   

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