| Grazing behavior of livestock is an important factors in transformational process which transform primary production to secondary, it is the major experimental and theoretical issues of behavioral ecology, feeding on interface of animal-plant is a central feature of grazing,as a key factor on production of animals and plants, feeding affects vegetation structure, grass decides the conversion efficiency of grassland resources, and reach the co-evolution between animals and plants, second, it is a valuable problems in actually grazing system, study of feeding behavior provides a solid theoretical foundation for grazing strategies and grassland management.Grazing behavior of goats by different grazing pressure index and grazing time shows: behavior of grazing livestock have a greater plasticity, growing season of grass or high grazing pressure index could cause a short supply on ground. At this time, goats will change the parameters of action, for example increase bite of ingestion, intake per bite,prolong ingestive time and so on, to increase food intake, meeting the needs of life activities; when the time on feeding increases, the time on the other behaviors such as wandering, bedding, maintenance will be shortened; as the season goes on, the growth of grass into a different period, forge nutrients changes, ruminant indicators of goat primary relates to quality of grass, so ruminating behavior of goat closely linked with season.The genetic diversity of 18 cultivars was estimated by ISSR Marker,15 ISSR primers generated 126 bands, of which 104 were polymorphic,6.93 polymorphic bands number was obtained averagely. The polymorphic percentage was 82.54%.The study showed:grazing pressure index and season all had an impact on goats, and there was an interaction between the two factors. The season of sufficient pasture supply would reduce influence of different grazing pressure index, these two factors interacted when forage lacked, aggravated the shortage of forage supply, changed the behavior characteristics in a large part, in the study of such problems must consider interaction under different factors. The relationship between grassland condition and grazing behavior parameter showed:when grass height is 16-20cm, the volume of forge is 6400-6800cm3/m2, or dry matter on the ground is 45-65g/0.25m2, goat grazing is relatively stable, and get enough food in less time. When grazing pressure index increased, the soil water in surface decreased, soil bulk density of 0-5cm layer increased with the increasing of grazing pressure index, when grazing, soil bulk density increased, but there was a less volatile under moderate grazing; there was about 90% underground biomass in 0-20cm soil layer of pasture, the biomass decreased with increasing grazing pressure index.Effects of grazing intensity and soil depth on total P,total N and total K were not significant (P>0.05),significant (P<0.05) and not significant (P>0.05), Total N content of heavy grazing decreased extremely significant (P<0.01) compared with that of control; the content of the soil organic matter had a downtrend with grazing intensity increasing, the content of control area and the same grazing area also had a downtrend with the increasing of soil layer, soil organic matter in 0-10cm and 10-20cm of light grazing were not significant (P>0.05), the soil organic matter in 0-10cm of heavy grazing and control were significantly (P<0.05) higher than that in 10-20cm and 20-30cm; the content of rapidly available N decreased significantly (P<0.05) with the increasing of grazing intensity, the content of rapidly available P were no significant (P>0.05) difference between control area and grazing area.
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