演替

Aims Spring ephemerals characterized by very short-term growth rhythm and specific biological traits in the Junggar Desert of China play an important role in succession of the desert plant community, maintenance of the desert biological diversity and conservation of water and soil in desert.

准噶尔荒漠分布的早春短命植物不仅具有十分独特的生物学特点，而且在荒漠植物群落演替、物种多样性维持及土壤改良与防治水上流失等方面具有重要的生态学价值。

ARIMA model was used to fit and forecast the succession grading series of the waterlogged lowland in Honghu City, and the result showed that this model was better in fitting and forecasting the change trend of succession grading of waterlogged lowland.

结果表明，ARIMA模型能较好地拟合并预测涝渍地演替级数的变化趋势。

The change of plant functional types' importance value shows: with the succession, annual or biennial forbs rapidly decrease then slowly increase, but overall decrease; perennial forbs increase firstly and reduce afterward; perennial grasses increase linearly.

植物功能群重要值变化分析表明：随着演替的进行，1、2年生杂草先迅速减小后缓慢增大，但总体减小；多年生杂草先增大后减小；多年生禾草类线性增加。

The age class structure of Salix oritrepha population in alpine, cloudy and wet area of east Qilian Mountian is studied ,on two levels of genets and their ramets and sprouting branches .The results show that genets population is very short of the first and second class seedlings,and most of seedlings belong to the third and forth classes, and the development trend of population on this level is stable;on the other hand,the age structure of remets and sprouting branches population is more complete,and its age class distribution chart likes triangle, belonging to increasing type.In general,Salix oritrepha population in this area is increasing, but its reproduct way have changed in community succession process in order to accommodate varying circumstances.

从无性基株个体种群和无性克隆分株及萌生枝种群两个层次上对东祁连山高寒阴湿地区山生柳种群年龄结构进行分析，结果表明：无性基株个体种群 0~10 龄级幼苗贮备严重不足，11~20 龄级苗木所占比重最大，种群动态呈稳定型；无性克隆分株和萌生枝种群年龄结构比较完整，结构分布图呈正三角形，种群动态表现为增长型；总体上来讲山生柳种群呈增长趋势，只是在演替过程中为适应环境其繁殖方式有所改变，导致现阶段山生柳种群两个层次结构状态。

The dominant species in the tree layer were found as Castanopsis chinensis, Endospermum chinense and Cryptocarga concinna . The Mesophanerophytes and Microphanerophytes were found having high percentage, and the Megaphanerop, Geophytes and Therophytes were notfound in the species life form spectrum of the community. The Mesophyll also had high Percentage in leaf-sizeclass spectrum of the community.

本群落以中、小高位芽植物占优势，缺乏大高位芽、隐芽和一年生植物叶型以中型叶为主群落的大部分优势种的种群分布格局是随机分布的优势种群的立木结构分析表明，本群落处于进展演替它与30a前比较有较大的变化乔木层原优势种黄桐、猴耳环、亮叶肉实等被锥粟、刺栲等替代。

Levins's and Shannon-Wiener niche breadth formula and Pianka's niche overlapping formulae are adopted to quantitatively study the niche breadths and overlapping feathers of major plant species in Malan forest standing in the Loess Plateau as well as analyze the niche patterns of these major plant species following their successions.

应用Levins、Shannon-Wiener生态位宽度公式和Pianka生态位重叠公式，定量研究了黄土高原马栏林区主要植物种的生态位宽度和生态位重叠特征，同时对主要种在演替系列上的生态位变化规律进行了分析。

This suggests that the diversity indices of lianas might be employed to measure forest succession.

在没有人类干扰的条件下，随着群落演替的进行，藤本植物的物种多样性逐渐减少。

The individual number, species number and Shannon-Wiener index of lianas in ravine rain forest and riv...

因此在某些地区，可以将藤本植物物种多样性的高低作为衡量森林演替阶段的一个指标

Dominated by mesophytes , the vertical structure of community is stable and the composition of every stand class

的规律，特别是由马尾松林向常绿阔叶林演替的规律，在理论和实际应用上都有着重要的意义。黑石

The results indicate that (1) with the increase of grazing intensities from light, middle, heavy to overgrazing, plant coverage and aboveground/belowground biomass decreases, the structure of plant community changes from simple to complexity and to simple, the type of plant community changes from mesophytes+xerophytes to xerophytes and to halophytes.

结果表明，随著放牧强度的增加，羊草草原的植被盖度和生物量随之降低，优势羊草群落将逐渐被盐生植物所替代，群落结构趋於简化，物种向旱生化和盐生化演替。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。