The Plant Composition In The Habitat And Food Resources Evaluation Of Rhinopithecus Roxellana In Shennongjia, China

Rhinopithecus roxellana,a rare and endemic species in China under the first rate national protection,is found in the provinces of Shannxi,Sichuan,Gansu,Hubei and some other places in China. Shennongjia,a national natural reserve in Hubei province,is the most eastern end where the Rhinopithecus roxellana is found.Eight groups of about 1 200 Rhinopithecus roxellana exist in Jinhouling and Qianjiaping,which are two areas in the Rhinopithecus roxellana reserve.The quantity of Rhinopithecus roxellana has been showing a steady growth trend in recent twenty years.From August 2006 to November 2008,nine trips there for the ecology observations of the Rhinopithecus roxellana have been made,mainly studied on plant composition of their habitat,the seasonal habitat selection,and food composition,nutrient composition of plant as food sources,selection of food habits etc.The results provide important scientific data for protection and scientific management of Rhinopithecus roxellana. The main results as follows:1.160 quadrates with total areas of 64000 m~2 were surveyed,and with the rise the elevation gradient,the changes of habitat plant composition,tree species diversity and structural changes were analyzed.289 species were found in samples belonged to 37 families,and 123 genera,in which there are 25 families,and 90 genera and 198 species trees,7 families,29 genera and 84 species shrub,5 families,4 genera and 7 species woody climber.The Dominant families are Rosaceae,Caprifoliacea, Lauraceae,Fagaceae,Ericaceae etc.According to differences of different species composition in tree layer of elevation,this area can be basically divided into three types of plants,they are deciduous broad-leaved forest(1900 m～2100 m),mixed coniferous broad leaved forest(2200 m～2 400 m) and dark coniferous forest(2500 m～2600 m).Diversity index(Shannon-Wiener index) shows a downward trend with elevation in the three vegetation types;evenness index(Pielou index) declines in the mixed forest and dark coniferous forest,while there is no significant diversification in deciduous broad-leaved forest.The diversity of tree species grows in sunny slope is lower than that of shady slope in deciduous broad-leaved forest and mixed forest;while the species difference of tree layer between sunny slope and shady slope are not significant.Proportion of tree layerⅠ(＞20 m) gradually decreased with the elevation in the tree layer,but the proportion of tree layerⅡ(10 m～20 m) has no significant change, while the proportion of tree layerⅢ(＜10 m) rises.Diameter at breast height used to instead of age to analyze the population age structure of habitat of nine kinds of dominant tree species,shows a steady growth trend of the tree layer in this area. 2.Quantitative analysis method was used in this article for the study of characteristics of ecological niche of dominant species in Qianjiaping area in Hubei Shennongjia reserve of Rhinopithecus roxellana habitats.It shows that in the habitat of tree layer in forest communities,the species with the highest niche width is Betula albo-sinensis(5.261),follow by Pinus armandii(4.545), Abies fargesii(4.289),Betula utilis(3.256);in shrub layer,Rhododendron erubescens has the highest, and follow by Salix polyclona(2.245),Crataegus wilsonii(2.064) and Malus kansuensis(1.453).To niche breadth more than 1,there are 30 kinds of main tree species,accounting for 10.38%of the total number,out of which there are 21 kinds of food plant of Rhinopithecus roxellana,accounting for 12.21 %of the total number of Shennongjia Rhinopithecus roxellana food plant.In the top of 25 essential value species,there are 18 kinds of plants for food sources,accounting for 74.50%of the sum.Seven pairs of species are above 0.4 in overlap value of dominant species niche;most of the similarity ratio values of species niche between 0-0.3,account for 83.82%in the total species.In short,the habitat Shennongjia Rhinopithecus roxellana has complex plant composition,and many dominant species are food sources;with highly similar dominant species habitats and more overlapping niche.3.Sample lines and quadrat methods were used to study habitat and bedding selection of Rhinopithecus roxellana in each season,12 ecological factors of habitat selection and 14 ecological factors of bedding selection are chosen for analysis.It shows that for Shennongjia Rhinopithecus roxellana,there is a significant difference between utilization of plants in habitat(F=4.85,P＜0.05) and selection on slope position(F=7.33,P＜0.05) in different seasons;significant differences are showed on the elevation(F=10.27,P＜0.01),gradient,(F=11.09,P＜0.01) hidden(F=21.76,P＜0.01),stand density(F=11.55,P＜0.01),food abundance(F=8.62,P＜0.01),tree average height(F=18.35,P＜0.01),average tree diameter at breast height(F=18.35,P＜0.01) and average height of all shrubs (F=13.62,P＜0.01);while there is no significant differences on slope direction(F=1.27,P＞0.05) and distance(F=3.17,P＞0.05) from the water source.Diversity average height of shrub(F=5.91,P＜0.05) at night is significant in different season;significant differences are showed on plant species(F=21.35, P＜0.01),gradient(F=7.50,P＜0.01),slope direction(F=18.66,P＜0.01),slope position(F=12.43,P＜0.01),hidden(F=58.38,P＜0.01) forest canopy density(F=37.14,P＜0.01),food abundance (F=53.88,P＜0.01),average height of trees(F=14.66,P＜0.01),and average tree diameter at breast height(F=11.84,P＜0.01),distance from tree(F=19.38,P＜0.01) and water source(F=17.95,P＜0.01);while there is no marked difference on ground elevation(F=2.69,P＞0.05) and distance from shrub(F=3.22,P＞0.05).4.Analysis to the degree of preference habitat in each season indicate that Rhinopithecus roxellana prefer to select the broad-leaved forest,mixed forest and coniferous forest habitation with altitude between 2 000 m and 2 600 m,enjoy playing on middle down-ward of slope location,and semi-sunny or semi-positive slope with gradient between 15°and 45°,and forest with high food abundance,but feeding also occurs at shady slopes in good weather of autumn and winter. Rhinopithecus roxellana require higher forest canopy density and hidden,often like to select canopy density from 30%to 80%,more preferred those above 80%,tree height from 10 m to 20 m,average tree diameter at breast height between 10 cm and 30 cm,shrub height from 3 m to 5 m,hidden between 20%and 50%,or play in higher hidden Forest.But selections of ecological factors of Rhinopithecus roxellana habitat are also varied in different seasons.Analysis of principal component indicate that in the spring,habitat selection of Rhinopithecus roxeUana is mainly affected by vegetation type,cover condition and food;in summer,they are mainly affected by vegetation type and hidden conditions;in autumn,they are still subject to vegetation types and hidden condition;while in the winter,they are mainly due to hidden conditions and the higher food.5.Requirements of overnight accommodation to Rhinopithecus roxellana ate higher.The survey shows that they enjoy to select the broad-leaved forest,mixed forest and coniferous forest with altitude from 2 000 m to 2 600 m as their overnight accommodation,and select upward slope with gradient from 15°to 45°between the semi-suuny or semi-positive slope,and also enjoy select hidden above 50%with canopy density stands from 50%to 80%,more preferred above 80%.Selection of tree height from 20 m to 30 m,Tree distance is less than 5 m,average tree diameter at breast height between 20 cm and 30 cm,and the shrub height from 1 m to 4 m,the nearest bush between 2 m and 3 m or more far than 3 m are enjoyed.They also like to select mountain forests with middle and high food abundance and distance to water resource from 500 m to 1 000 m or far away 1 000 m.However,in different seasons, Rhinopithecus roxellana select various ecological environments of overnight accommodations.Analysis with principal component show that,in the spring,selection of overnight accommodation affected by plant type,food and hidden conditions;in the summer,mainly impacted by plant type,terrain factors and the hidden conditions;in the autumn,mainly due to topographical,food,plant type and hidden conditions;while in winter,it is mainly affected by hidden conditions,food and the effects of topographical factors.6.With survey of literature and habitat quadrat,it is found that Rhinopithecus roxellana in Shennongjia area has 202 kinds of plants for feed,belonging to 44 families,89 genera;Among them, there are 181 species of woody plants,17 kinds of herbaceous plants and 4 kinds of tree-type clothing plant,accounted for 89.60%,8.42%and 1.98%respectively of the total number of plant species for food in Shennongjia.the statistics also show that plants can feed mainly concentrated in the 17 families (more than 5 families),they are Rosaceae(9 genus / 32 species,the same as follow),Lauraceae(4/15), Caprifoliaceae(5/14),Fagaceae(5/10),Actinidiaceae(2/8),Oleaceae(4/8),Pinaceae(3/7),Salicaceae (2/7),Comaceae(3/6),Corylaceae(2/6),Celastraceae(2/6),Berberidaceae(2/5),Lardizabalaceae(3/5), Umbelliferae(2/5),Balsaminaceae(1/5),Schisandraceae(1/5)and Ericaceae(1/5),which account for 38.64%in the total number of food plant families to Shennongjia Rhinopithecus roxellana,51 genera in total,149 species,account for 57.30%and 73.76%in the total number of food plant genera and species respectively.7.With survey of quadrat region for activity of Rhinopithecus roxellana in Sbennongjia Qianjiaping areas,it was recorded 93 species of food plants,belonging to 33 families and 63 genera. They can be divided into three categories according to plant relative abundance(RA) in variety communities of food plant,that is RA＞5,1＜RA＜5 and RA＜1.In spring,there are 7 species of plants with RA＞5,that are Betula albo-sinensis,Betula utilis,Carpinus eordata,C.simplicidentata,Fagus engleriana,Quercus aliena and Q.spinosa vat.acuteserrata.There are 32 species of plants with 1＜RA＜5,that are Comus controversa,Populus lasiocarpa,D endrobenthamia japonica vat.chinensis etc.45 species of plants with RA＜1,that are Cerasus buergeriana,Schisandra chinensis,Stachyurus chinensis, S.glaucescens etc.In summer,there are 3 species of plants with RA＞5,that are Decaisnea fargesii, Crataegus wilsonii Satg and Crataegus hupehensis;almost 40 species of plants with 1＜RA＜5,that are Sorbus zahlbruckneri,Betula utilis,Betula albo-sinensis,Carpinus cordata,vat.chinensis etc.,and 31 species plants with RA＜1,that are Schisandra chinensis,S.incarnata,Us nea montis-fuji,U.aciculif era and etc.;In autumn,there are 5 species plants with RA＞5,that are Pimus armandii,Abies fargesii, Crataegus hupehensis,Malus hupehensi,Malus kansuensis and etc.,34 species plants with 1＜RA＜5, that are Crataegus wilsonii,Quercus aliena,Quercus aliena vat.acuteserrata etc.,13 species plants with RA＜1,that are Schisandra sphenanthera,Rosa caudata,Sinofranchetia chinensis,Euonymus elegantissimus etc.;In winter,there ate 12 species of plants with RA＞5,that are Pimus armandii fransh, Abies fargesii,Helwingiajaponica,Malus kansuensis etc.,4 species plants with 1＜RA＜5,that are Lichen Usneae Montis-fuji,U.longissima,U.aciculifera and U.luridorufa.It can be seen from Plant resources of Rhinopithecus roxellana,most RA value is between 1 and 5 in spring,summer and autumn, which also reflects spatial and temporal changes of food plants in Shennongjia reserve and the complex feeding of Rhinopithecus roxellana.8.Microscopy analysis to excrement residuum of Rhinopithecus roxellana shows that 54 species of plants,including 59 parts constitute the main food components in each season,accounting for 26.73%in feeding plants.In spring,there are 4 species of plants with r＞5,that are Carpinus cordata vat.chinensis,Hetwingia japonica,Fagus engleriana and Betula albo-sinensis,and 15 species of plants with 1＜r＜5,that are Comus controversa,Decaisnea fargesii,Acer davidii,Rhus chinensis etc.,both of them account for 74.04%in food components in spring,which are their main food plants.In summer, there are Carpinus cordata var.chinensis,Fagus engleriana with r＞5,and 20 species of plants with 1＜r＜5,they are Decaisnea fargesii,Betula albo-sinensis,Helwingia japonica,Crataegus wilsonii etc., both of them are taken together accounted for 68.35%of food composition,and become the main food types in summer;In autumn,there are 7 species of plants with r＞5,they are Pimus armandii,Malus hupehensi,Crataegus hupehensis,Crataegus wilsonii etc.,and 15 species of plants with 1＜r＜5,that are Abies fargesii,Rosa omeiensis,Euony mus alatus,Cor ylus ferox vat.thibetica etc.,which account for 81.30%of composition of food in autumn,and become the main food types;In winter,there ate 8 species of plants,that are Pimus armandii,Malus kansuensis,Helwingia japonica,Lichen Usneae Montis-fuji,U.aciculifera etc.,which account for 52.91%in food composition of Rhinopithecus roxellana,and become main food types in winter.9.Analysis of feeding-associated factor to Rhinopithecus roxellana in each season shows that average food abundance(t=2.492,P=0.088) has no significant difference(P＞0.05),while average water content(t=4.155,P= 0.025,P＜0.05) in the main food plant in each season,content of crude protein(t=14.196,P=0.001,P＜0.01),crude fiber(t=5.921,P=0.010,P＜0.05),crude ash(t=14.487, P=0.001,P＜0.01),crude fat(t=7.167,P=0.006,P＜0.01) and NFE(nitrogen free extract)(t=7.846, P=0.004,P＜0.01) reach to a significant level.It shows that food selection of Rhinopithecus roxellana is not determined by a single factor,but combined effects of various factors;and also shows that complex food selection.From the analysis of seasonal food source of plant nutrients principal component,we can see that in spring,feeding of Rhinopithecus roxellana is mainly affected by crude protein,NFE,water content and food abundance;and impacted by NFE,crude fiber,crude ash and food abundance;while in winter,crude fiber,crude fat,crude protein and food abundance are main factors which impact feeding of Rhinopithecus roxellana.