There are divers breeding systems in the flowering plants, and different breeding systems have different ways of avoiding or promoting inbreeding or outbreeding. Flexistyly is a new behavioral outbreeding mechanism recently found in Alpinia ginger plants.

We investigated the distribution of clonal and non-clonal plants along the sandy hill-slope in Ordos Plateau, using the line intercept method and the point method. One-way ANOVA was used to compare the difference of species richness and importance of plants with different growth forms among communities along the sandy hill-slope. We used the regression analysis method to analyze the relation of species diversity to importance of clonal plants in the communities. Species richness of clonal plants was higher in the ridge summit and the mid-slope, while lower in the foot-slope. The same trends were found for non-clonal plants, their species richness in the ridge summit and mid-slope was higher than that in the foot slope. Variation of species richness of phalanx clonal plants was similar to that of non-clonal plants. Guerilla clonal plants were absent in the ridge summit and few in the mid-slope, while abundant in the foot-slope. The importance of clonal plants in the foot slope was higher than in the ridge summit and the mid-slope. The importance of non-clonal plants in the foot slope was lower than in the ridge summit and the mid-slope. The importance of clonal plants was higher than the non-clonal plants in the mid-slope and the foot slope, while there was no such a difference between them in the ridge summit. The importance of phalanx clonal plants in the ridge summit and the mid-slope was much higher than that in the foot slope. In contrast, the importance of guerilla clonal plants in foot slope was much higher than that in ridge summit and mid-slope. The importance of phalanx clonal plants was higher than that of guerilla clonal plants in both the ridge summit and the mid-slope, while in the foot slope, the importance of guerilla clonal plants was higher than that of phalanx clonal plants. In the ridge summit, the relations of community plant species diversity to importance of clonal plants, importance of non-clonal plants as well as importance of phalanx clonal plants were parabola. In the mid-slope, plant species diversity increased with increasing importance of non-clonal plants, while it decreased with increasing importance of clonal plants as well as importance of phalanx clonal plants. In the foot-slope, plant species diversity was positively correlated to the importance of non-clonal plants, and negatively correlated to the importance of clonal plants as well as importance of guerilla clonal plants. Our results confirmed that clonal growth in plants is adaptive in general under stressed conditions, and clonal plants are more important in stressful habitats. There are marked differences between phalanx and guerilla clonal plants in their optimal locations along the sandy hill-slope. Phalanx clonal plants are more abundant and more important in drier habitats. In contrast, guerilla clonal plants tend to be more abundant and more important in wetter habitat. This suggested that phalanx clonal plants seem to have strong ability to grow under stressed environments. In the community located in ridge summit, Shannon-Wiener index increase and then decrease with increasing importance of clonal plants. In mid-slope and foot-slope communities, Shannon-Wiener index decrease with increase importance of clonal plants owing to their strong spreading ability.

Determining individual ages of endangered plants is the purpose of studying its age structure and population dynamics. There are three main methods of determining individual age, but all have their shortcomings, such as low precision, worse serviceability

The characteristics of the height structure of Bruguiera gymnorrhiza population in National Shankou Mangrove Nature Reserve were studied by measuring the fractal dimension of height contour. The results showed that the height structure of B. gymnorrhiza p

Genetic diversity of four populations of Tsoongiodendron odorum, Nankunshan and Chebaling of Guangdong Province, Jingxi of Guangxi, and Bawangling of Hainan Province was examined by Random Amplified Polymorphic DNA (RAPD). A total of 224 sites were detect

Endophytes or endophytic fungi are a kind of fungi that live inside plants. They widely exist in higher plants, particularly in grasses. The fungi are members of class Ascomycetes, family Clavicipitaceae, tribe Balansiae, including some imperfect fungi th

Seed dispersal is a multi-step process, which may include fruit removal, seed dissemination, postdispersal seed predation, potential secondary dispersal, seed germination, and seedling establishment. Previous studies often focused on only one or a few of

In order to understand the degradation process and its mechanism on Inner Mongolia Typical Steppe, clonal morphological plasticity and biomass allocation patterns of two dominant species, Artemisia frigida and Potentilla acaulis were studied under differe

Longan (Dimorcarpus longana Lour. cv. Wulongling) seedlings of two different ages grown in pots were selected to study the effects of acid rain stress on gas exchange, and chlorophyll a fluorescence parameters and their recovery. Sulfuric acid and nitric

Sunflecks, which penetrate through the canopy, have been proven to be of great ecophysiological importance. Plants show enhanced photosynthesis capacities under fluctuant light, but these capacities exhibit remarkable variation among species and individua

Research has shown that plants are adversely affected by different wetting and fertilized zones. Most studies that have been done were limited to the effect of irrigation or fertilization. This study was done to detect the influence of various fertigation

Sweet pepper (Capsicum annuum L.) grown under water condition was used to study the distribution dynamics of nitrogen absorbed at the early flowering stage using 15N tracer. The results obtained are as follows: The accumulation dynamics of vegetable organ dry matter display a rapid linear increase, and the fruit topped the other organs from the earlier profuse fruiting stage. The nitrogen concentrations were keeping steadily at same levels in root and fruit from the early picking stage. In the leaves, it decreased rapidly with development and was not much different from the root and fruit at the profuse fruiting stage, but had twice the concentration of the stem and branch. The nitrogen accumulation dynamics were similar to the dry matter. Most of the labeled nitrogen absorbed at early flowering stage by the roots was distributed and reserved in the leaves. It was found that about half of the labeled nitrogen absorbed at early flowering stage was transported to the neonatal part of the plant after two weeks and the translocation of absorbed labeled nitrogen began to decrease significantly after 4 weeks. After 6 weeks there was little of labeled nitrogen to be transported into the neonatal part of the plant. Newly absorbed nitrogen was transported into the other stronger parts of the plant more easily and with a higher reutilization rate. The longer the nitrogen existed in the organs of the plant, the lower the reutilization rate. The fruit has the most competitive ability for nitrogen among the different organs of the sweet pepper plant during the fruit harvest period. On the whole plant level, the transport of the labeled nitrogen from vegetative organs to the reproductive organs is affected not only by the intensity and capacity of the nitrogen sink competition, but also by the transport time for the labeled nitrogen absorbed at the early flowering stage.

A study on the cycling of N and P in a pure forest of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook. and a Chinese fir-Tsoongiodendron odorum Chun mixed forest (2 Chinese fir： 1 T. odorum) over two years was carried out in Sanming, Fujian, China. For

Process-based equilibrium terrestrial biosphere models — BIOME series models (BIOME1: Prentice et al.，1992；BIOME2: Haxeltine et al.，1996；BIOME3: Haxeltine & Prentice，1996；BIOME4: Kaplan，2001) and their development to a dynamic global vegetation model (LPJ

Research on the effect of vegetation on soil and water conservation in China can be divided into three main aspects. The first is the research of contrast, which is the research of vegetation benefits on blocking runoff and sediment by contrasting field o

Hydro-ecological effects of Populus davidiana stand have been studied in the paper using long-term observation. The results of the studies show that the total intercepted amount in canopy of the stand in six years is 309.5 mm, and the average intercepting

Landform plays an important role in regulating the spatial pattern of plant community. Quantifying the spatial pattern of plant community along the sand-covered hillslope can give useful information about the relationship between vegetation and environmen