The Plant Composition And Their Relative Edibility Of Rusa Unicolor And Budorcas Taxicolor In Winter And Spring In Anzihe Protected Area,Sichuan Province

The study of feeding plants is one of the most important research contents in the protection of rare and endangered large herbivores,which can be an important basis for the formulation of animal protection strategies,especially in the season of food shortage.Here,the food plants of Rusa unicolor and Budorcas taxicolor in Anzihe protected area,belonging to Qionglai Mountains,Sichuan Province,were taken as our study objects.The direct observation methods,utilization techniques and high throughput sequencing approaches(HTS)were used to identify and analyze the feeding plants for R.unicolor and B.taxicolor in winter and spring,and did the relative researches according to the relative plants in the fecal samples.In the mean time,according to the specific fed parts of the feeding plants,we sampled the related plants to examine and analyze the content of crude protein,crude fat,crude fiber,total amino acids,water,tannin and total phenols.The main results were as follows:(1)Many kinds of plants were the food resources for R.unicolor and B.taxicolor in winter and spring.In addition,they shared a lots of feeding plants in the food resources: the feeding plants of R.unicolor were 94 genera,belonging to 50 families,and 92 genera,belonging to 56 families in winter and spring,respectively.The feeding plants of B.taxicolor were 105 genera,belonging to 59 families,and 87 genera,belonging to 49 families in winter and spring,respectively.The shared plants of R.unicolor and B.taxicolor in winter were 73 genera,belonging to 43 families.Whereas,the shared plants were 69 genera,belonging to 44 families in spring.Among these,Rubus,belonging to Rosaceae,was the most predominant plant for R.unicolor in winter and spring,B.taxicolor in winter,while Eurya,belonging to Theaceae,was the most predominant plant for B.taxicolor in spring.(2)The feeding performances of R.unicolor and B.taxicolor in winter and spring were in accord with the Optimal Foraging theory.Through adjusting the dietary diversity and niche breadth,they could adapt to the environmental change and utilize the resources for better: the dietary diversity of R.unicolor in winter and spring,B.taxicolor in winter was significantly higher than that of B.taxicolor in spring(P < 0.05),whereas there was no significantly difference in the food diversity among R.unicolor in winter and spring,B.taxicolor in winter(P > 0.05),and the food diversity of R.unicolor in winter was slight superior to that of R.unicolor in spring.The dietary niche breadth of R.unicolor in spring was significantly higher than that of B.taxicolor in winter(P < 0.05),but there was no significant difference in dietary niche breadth among R.unicolor in winter,B.taxicolor in spring and R.unicolor in spring or B.taxicolor in winter(P > 0.05),and that of B.taxicolor in spring was slightly superior to that of B.taxicolor in winter,in line with R.unicolor.(3)There existed differences in the utilization of food resources between R.unicolor and B.taxicolor in different seasons,they could adapt to environmental change through dietary niche adjustments and dietary niche partitioning,which showed a strong environment adaptability and utilization of resources for R.unicolor and B.taxicolor: the number of OTU(Operational Taxonomic Unit)types of R.unicolor in winter was significant higher than that of R.unicolor in spring(P < 0.05),but contrary to that for B.taxicolor.The significant dietary overlap only existed between R.unicolor and B.taxicolor in winter(0.7030 > 0.6).In addition,the dietary niche partitioning was significant between R.unicolor and B.taxicolor in winter and spring(P < 0.001).And the NMDS plot showed that the niche range of R.unicolor in winter was smaller than that of R.unicolor in spring,while that of B.taxicolor in winter was bigger than that of B.taxicolor in spring.(4)The plant composition fed by R.unicolor and B.taxicolor have the characteristics of desirable nutrient content,low content of tannin and total phenols.After selection,we found that the whole plants of Urtica Fissa,Laportea bulbifera,Lecanthus peduncularis,Iris confusa,Paeonia veitchii,Pilea sinofasciata,Thalictrum delavayi,Corydalis anthriscifolia,Spiraea myrtilloides,Rubia cordifolia,Stellaria media,Impatiens undulate,Equisetum diffusum and Boehmeria silvestrii,the branch leaves of Salix variegate,Hydrangea Macrophylla,Helwingia japonica,Hypericum patulum,H.xanthoneura,Cotoneaster moupinensis,the leaves of Berberis silvataroucana,the stems and leaves of Fargesia robusta and the barks of Rhododendron argyrophyllum were fed together by R.unicolor or B.taxicolor would be complementary in intake of crude protein,crude fat and total amino acids,and could diminish the intake of crude fiber,tannin and total phenols.Which would effectively improve the nutritional value per unit mass of plants.Therefore,R.unicolor and B.taxicolor fed on a variety of plants as their food and shared a lot of plants in winter and spring.Their feeding habitats conformed to the Optimal Foraging theory.Namely,their dietary diversity,niche breadth was larger and wider in spring,the relative dietary overlap was less,and the niche partitioning was significant in different seasons.Which indicated that R.unicolor and B.taxicolor had a strong environmental adaptability and resource utilization.According to the above rusults,these above mentioned plants can be reasonably designed for vegetation restoration projects in the degraded habitat for R.unicolor and B.taxicolor in Qionglai Mountains,which will greatly improve the food condition of R.unicolor and B.taxicolor in the season of food shortage,ensure nutrition intake and greatly promote the protection of R.unicolor and B.taxicolor.