Font Size: a A A

Preliminary Studies On Regrowth Eco-biology Of Seriphidium Transiliense

Posted on:2009-08-28Degree:DoctorType:Dissertation
Country:ChinaCandidate:Z J SunFull Text:PDF
Abstract/Summary:PDF Full Text Request
Severe degradation of sagebrush desert in spring and autumn have became the bottleneck that restricted development of seasonal stock raising in North area of Xinjiang. Reasonable utilization of sagebrush desert was the key for sustaining development of grassland resource in Xinjiang. In order to reasonable utilize, renovate and develop continuely sagebrush desert of spring-autumn, study on growth rhythm, change and difference on flexibility nutrition substance of Seriphidium transiliense under different utilizing model and beginning grazing-period of sagebrush desert were discussed, which widely distributed in Northern Slope of Tianshan Mountains.The main results were the flowing:(1) Seriphidium transiliense was begin to return green between the beginning of March and middle of March, tillering period was between the middle of April and the beginning of June, buding period was between the middle of June and middle-last of Augest, ablooming period was at the beginning of September, seed was appeared after the last of September, and seed maturity was between the middle of October and last of October. Phenophase of S. transiliense had certainly fluctuation at different years.(2) Height and tiller weight of S. transiliense were linearity increased during whole growth season, and emerged in a'rapid-slow-rapid'shape on rate of growth. Curved shapes of the tiller quantity and the leaf biomass had"increase-reduce-increase"and"double growth peaks"respectively. The root biomass had no distinct difference, aboutindividual plant was 6.1g, the whole yield and aboveground biomass of S. transiliense emerged in"S"shape and aboveground biomass of S. transiliense was mainly part of whole yield in desert pasture. Hence desert pasture of S. transiliense was suitable for grazing from April to June in spring, from September to October in fall during whole growing season, which could avoided period of low-vale or slow-growth in individual.(3) The crude protein and sucrose were the dominating nutrition substance of S. transiliense. The seasonal changes of soluble carbohydrate and sucrose contents of S. transiliense emerged in an'up-down-up-down'trend between 4th May and 14th November and appeared on different in roots, stems and leaves. Starch of leaves appeared'single peaks', stems appeared'down-up-down'trend and no rule in root. The crude protein of leaves appeared'single peaks', no changes in roots and the trend of bellowing in stem.The contents of flexibility nutrition substance had finished storage in roots before 17th October.(4) Grazing had certainly effect on delaying phenophase on budding, blooming and seeding, about 10~15d. Grazing could obviously reduced height of plant, and had no difference on forbidding grazing and continuous grazing. Seed-ability, seeding appear period and quantity of S. transiliense on perennial enclosure pasture were higher than that of forbidding grazing pasture, but 1000-grain weight was on the contrary, and maturity of seed could not producted in continuous grazing pasture.(5) Leaves and tiller weight of S. transiliense had obvious discrepancy among three utilizing model, and the order of weight was perennial enclosure pasture>continuous grazing pasture≈forbidding grazing pasture. Root weight had no discrepancy among three utilizing model, and trend of growth had certainly difference, curved shapes on forbidding grazing pasture and continuous grazing pasture was"descend -increase-descend-increase". The tiller quantity had obvious discrepancy among three utilizing model in prophase of growth (before 24th August), and appeared'up-down-up'. Perennial enclosure could stimulate individual growth potential of S. transiliense, added the coverage of community, and forbidding grazing had no effect on S. transiliense individual. The cracking degree of root-stem had obvious discrepancy (p<0.01), and as could be evaluated grazing intension of Artemisia sagebrush desert.(6) The contents of flexibility nutrimental substance had significiant differnce in S. transiliense among three utilizing model (p<0.01). Soluble carbohydrate and sucrose contents emerged in an'up-down'trend, and the highest at perennial enclosure pasture, the lowest at continuous grazing pasture. The changes of starch contents had more complex, respectively appeared'single peak','double peaks'at leaves and stems of S. transiliense, and the highest at perennial enclosure pasture. The order of starch contents of roots was perennial enclosure pasture> continuous grazing pasture>forbidding grazing pasture. Crude protein contents of leaves and roots appeared'descending','descend -increase-descend'respectively, more varieties at stems, and the highest contrnts of roots, the lowest of leaves and the middle of stems was at continuous grazing pasture.(7) Coverage, height and density of S. transiliense had no discrepancy before simulating grazing intensity (p>0.05), had significiant difference among aboveground yield (p<0.01) and the order was'super grazing>high grazing>middle grazing≈light grazing'. After resuming, S. transiliense had all died at super grazing. Except coverage in spring, there was no difference on regrowth height, density, coverage of S. transiliense among high grazing, middle grazing and light grazing, but effect of renewing was best at middle grazing and light grazing. According to currently development of stockbreeding and crude protein and crude fat contents of S. transiliense appeared'light grazing>middle grazing>high grazing>super grazing, middle grazing was suitable to the spring- autumn desert pasture of S. transiliense. (8) Coverage and density of S. transiliense had no discrepancy among different beginning grazing-period at the same grazing intensity (p>0.05), had significiant difference among aboveground yield and heigh. After resuming, S. transiliense had all died at super grazing. In spring, regrowth height of S. transiliense had significant difference (p<0.01), and that of between 1st April and 15th April was best, Coverage of resuming was quicker on 15th April, density had no discrepancy (p>0.05). In autumn, regrowth height, coverage and density of S. transiliense had no significant difference (p>0.05) among different beginning grazing-period, but effect of renewing was better between 15th September and 1st October. According to crude protein, crude fat contents of S. transiliense appeared the trend of descending and grazing intensity, the Beginning grazing-period was at 5th April in spring, from 15th September to 1st October under middle grazing, which was propitious to the continuely development of S. transiliense sagebrush desert.
Keywords/Search Tags:Seriphidium transiliens, flexibility nutrition substance, module, dynamical measuring, beginning grazing-period
PDF Full Text Request
Related items