Investigation And Analysis Of The Fitness And Habitat Situation Of The Dafeng Milu Population

In 1986,Dafeng Milu Nature Reserve reintroduced 39 milu from UK under the support by the National Forestry Department of China and the World Wildlife Fund.In 2016,the milu population had increased to 3223,among which 295 were wild.Degradation of the milu habitat in contrast to the development of the milu population is also becoming increasingly problematic.Our research is divided into three parts:the first part is the basic research,including the first and second chapters,mainly elaborate the research background,research significance and research area profile;the second part is a comprehensive analysis,including the third and fourth chapters,mainly investigated the breeding situation of milu population under different grazing conditions and the status quo of the plant resources of the milu habitat.The third part is the comprehensive discussion,including the fifth chapter,put forward the concrete solution based on our research results.The data obtained from this study showed that there are differences in the birth rate,mortality and reproduction rate of the milu population under the three grazing conditions in the Dafeng milu Reserve.The average annual breeding rates are varied as the tendency following as complete wild grazing>semi-free>artificial captivity.The ratio of the average birth rate to the mortality rate of the milu population(i.e.,R(B/D))in the three different grazing conditions in the past nine years is the tendency following as complete wild grazing>semi-free>artificial captivity.After the paired sample test:(1)About the birth rate:When compared the artificial captivity state of the milu population with semi-free and complete wild grazing respectively,the difference is extremely significant;but there was no significant difference between the birth rate of semi-free and complete wild grazing;the results indicated that the birth rate of milu under the artificial captivity was reduced compared with semi-free and complete wild grazing.(2)About the mortality:The difference between the semi-free and complete wild grazing was significant,while comparing artificial captivity with complete wild grazing there was similar;the results indicated that the mortality of milu under semi-free was higher comparing to complete wild grazing and artificial captivity.(3)Reproductive rate:semi-free and wild grazing are reciprocal resemble.The difference between the artificial captivity and complete wild grazing was very significant.The breeding rate of the milu is lower than that of the semi-free and the wild population.According to the ratio of birth rate,mortality rate,average annual birth rate to mortality rate R(B/D)and paired sample test,complete wild grazing is more conducive to the reproduction of the milu population.With respect to the species component,population structure in the first wild grazing area,we conclude Pennisetumis sp.is the dominant species and serve as the main food resource.The privileged milu habitat at eastern moisture grassland shows a smaller average height of Pennisetumis sp.which is only 12.2cm while it is 30cm in forest at eastern area.Similarly,Pennisetumis sp.height at western area is 16.6cm at grassland but 57.2 at forest.It is obvious that the milu population has significant higher mobility at moisture grassland than forest,and consequently results in a smaller Pennisetumis sp.height at eastern moisture grassland.The comparison of density,coverage,height and dry weight of Pennisetumis sp.in the feeding and non-feeding areas show significant differences.The density of Pennisetumis sp.in the non-feeding area is 13.3 plants per square meters while it is 1.99 plants per square meters in the feeding area.The coverage of Pennisetumis sp.in the non-feeding area is 94.8%while it is just 3.75%in the feeding area.The height of Pennisetumis sp.in the non-feeding area is 146.5 cm,while it is 9.04 cm in the feeding area.The dry weight of Pennisetumis sp.in non-feeding area is 2444 g/m2,while it is 10.06 g/m2 in the feeding area.It is presumed that the excessive feeding and trampling of milu directly deteriorate its habitat.Based on the investigation and analysis of this study,practical suggestions were given in order to protect the population and promote the healthy,sustainable development of the milu population,that is,reasonable planning,rotational grazing;silage harvest and artificial feeding;Returning to nature,reshaping their wild;Union protection,evacuation exchange;Use of resources,rational development,etc.