Shading Effects On The Growth Of Trifolium Repens

This article takes the leguminous plant white clover as the main research object, studied the effects of different shade treatment on the growths characteristics and the shape characteristic as well as the partition of energy, also study the ecology response of white clover. This research has selected the field experimental simulation method. This study started from June 6, 2006, ended on September 11. Shade treatments divide into no shade (0%), shade (50 %, 75 %, 85 %, and 95 %) 5 levels, the material which shielded light was the black sunshade net. Also studied the relationship between the rainfalls and the temperature to the white clover, find that there is not remarkable relevance between the rainfalls and the temperature to the white clover's growths. In the experiment, white clover in shade 85% and shade 95% were died one after another in a short-term, therefore this study mainly revolves white clover in entire illumination, shade 50% and shade 75% three kinds of treatment.In the vegetal period different time entire illumination (Cont.) under the condition stolon the stem elongates, new is long, the stem density all obviously is higher than provides shade treatment, is Cont.> in turn; S50> S75. The leaf density, the root density display and stolon the same tendency. The result indicated provided shade has suppressed white clover on and the underground partial growths, had proven once more white clover took one kind of sun plant, it was very strong to the light dependence。Provides shade has suppressed stolon growth, but to stolon the diameter has not affected, different time entire illumination, provides shade 50%, provides shade 75% treatment stolon diameter not remarkable difference; The leaf area also displays shows off the same result, differently processes the leaf area basically same, this also is sun plant's performance, the area is invariable under providing shade or reduces, but the leaf area of bear-shade plant generally can increase under shading effect; The entire light treatment root length obviously is bigger than provides shade treatment, displays it fully to occupy to the soil resources, also explained the white clover survivals nutrients mainly come from the photosynthesis, but is not depends upon the root from the underground gain under, therefore provides shade white clover certainly not to be able to assign more energies acceleration root to grow, on the contrary is reduces the root partition of energy to guarantee stolon and leaf's growth.Differently processes the white clover total biomasses as well as various components (root, stem, leaf) the dry weight difference is remarkable, according to the order is Cont.> in turn; S50> S75;During different treatment unit stolon length dry weight, between unit leaf dry weight not obvious difference under, but provides shade the unit root dry weight reduction.Without shade white clover branchings quantity many, provides shade processes the white clover branchings to be few. The branching densely goes higher means white clover occupy the area bigger, entire light treatment white clover display the crowded characteristic, that is "the use strategy", depends upon the big area to seize the habitat fully favor its occupies spatial the resources. Provides shade causes the white clover branchings intensity and the branching angle changes, differently processes the branching intensity size in turn is S75> S50> Cont., the branching angle size is Cont.>in turn; S50> S75. Under provides shade the branching intensity increase and the branching angle reduces is advantageous "runs away to white clover leaves" provides shade this kind of disadvantage oushabitat, seeks suits the growth the environment. Also is provides shade processes white clover to display the guerrilla warfare characteristic, that is "occupies the strategy", expands rapidly in the horizontal direction, forms a near straight line minute chain.The research under discovered provides shade the petiole universal long to not to provide shade, during different treatment changes is not big. This kind of response pattern was considered with the petiole took the leaf blade vertical strut structure the function is consistent, under a darker condition forms a longer petiole is advantageous to puts the leaf higher and lighter ,favor gains more light resources.White clover receive provides shade forces when reduces assigns for the root energy, will maintain to the stem and leaf's partition of energy. Like this is advantageous to white clover runs away to the disadvantageous environment, and occupies the superiority in the vertical space, gains the more light resources.Generally speaking, the white clover's growths is restrained obviously when it is overshadowed, therefore in the construction of artificially mix-seeds pasture, we must pay attention to the overshaded effect of other grazings to white clover, suggested carries on suitably mows to avoid the affects to the white clover output; But in the lawn virescence aspect, plants white clover are supposed to the sunlight sufficient place, not to shade as far as possible surpasses 50% of building shady place and the forest land, may choose like Liriope spicata, Carex giraldiana kiik and so on.