An investigation was taken on wild medical plants resources in Nangeng and Chaoba village which are Li minority in Baoting county,Hainan province.The investigation shows that there are 225 species(186families,83 genera) of vascular plant,including 6 species(6 families,6 genera) of fern,2 species(2 families,2 genera) of gymnosperm and 217 species(75 families,178 genera) of angiosperm.It contains 13 species of Hainan endemic species(Cycas hainanensis C.J.Chen、Cyclea hainanensis Merr.、Stephania hainanensis H.S.Lo et Y.Tsoong.、Firmiana hainanensis Kosterm.、Nephelium topengii(Merr.)H.S.、Dalbergia odorifera T.Chen etc.),7 species of national protected plants(Cyathea podophylla(Hook.) Cop.、Euphoria longan(Lour.)Steud.、L.chinensis Sonn.var.cuspontanea Hsue etc.),5 species of protective plants in Hainan province(Cratoxylon ligustrinum(Spach.)Bl.,Amesiodendron chinense(Merr.)Hu,Euphoria longan(Lour.)Steud.,Litchi chinensis Sonn.,Nephelium topengii(Merr.)H.S.etc.) and 15 species of folk medicines which are not recorded in documents or were not further studied before(Casearia membranacea Hance,Mukia javanica(Miq.) C.Jeffrey,Trichosanthes bracteata Voigt etc.).After analyzed the families and genera's characteristics of the medicinal plants resources of Li minority in Baoting county,the results show that those medical plant resources distribution is more centralized in families(Papilionaceae,Euphorbiaceae,Compositae,Zingiberaceae,Verbenaceae,Rutaceae,Saplandaceae,Umbelliffrae and Rubiaceae etc.) but is comparatively scattered in genera(only 30 genera have 2 and more than 2 species in 186 genera).

Big and small structural picture and survival curve were chosen to research the population dynamics of Pinus latteri.With methods including diffusion coefficient,Lloyd's mean crowding,patchiness index and Morisita's index,the distribution pattern was studied.The space pattern was analysed with Greig-Smith method,population structure and distribution patteren of P.latteri in Bawangling National Nature Reserve,Hainan Island were studied.The results showed that the population structure of P.latteri was a relativly stable type,however,the seedlings and saplings were scarce.The survival curve trended to be the type Deevey Ⅰ.The survival rate of young seedlings was low when dbh was under 2.5cm,while it began to increase during the saplings period,and reached the highest in the medium-sized population.However,the survival rate started to decline in the mature period,and the mortality rate was highest during the aged period.The population pattern was crowding type as a whole,the population pattern scale was between 100 square meters and 400 square meters.

Objective To analyze the constituents of the essential oil from Horsfieldia hainanensis Merr.MethodsThe volatile oil was obtained by steam distillation.The chemical constituents were separated and identified by gas chromatography-mass spectrometry(GC-MS).The relative contents were determined by area normalization.ResultsThe extraction rate of Horsfieldia hainanensis Merr.leaves was 0.11%.11 compounds were separated and identified,which accounted for 100% of the essential oil of the skins.The main chemical components of the essential oil were 3,7,11-trimethyl-,1,6,10-Dodecatrien-3-ol(46.03%),(-)-Globulol)(8.39%),adipic acid,dioctyl ester(7.03%),Ledol(7.00%),Copaene(5.86%),etc.ConclusionThe essential oil of leaf of Horsfieldia hainanensis Merr.is studied for the first time.It has provided scientific foundation for exploitation and utilization of Horsfieldia hainanensis Merr.

在对海南岛南端与北端沿海低山丘陵植物区系进行实地调查的基础上,对两个地区植物物种组成进行了比较研究。结果显示两地物种组成既有相似性也有差异性:琼南有种子植物876种,隶属于112科484属,植物区系以热带成分为主,兼有一定的温带成分和中国特有成分,且海南特有成分较高,具有一定的过渡性;琼北有种子植物934种,隶属于141科580属,植物区系以热带分布类型为主,同时有一定的温带成分,海南特有成分较高;两地植物区系的共同点是:均具有种类丰富、地理成分多样、优势成分明显、热带性质较强等。

OBJECTIVETo analyze the constituents of the essential oil from the bark of Horsfieldia hainanensis.METHODSThe volatile oil was obtained by steam distillation. The chemical constituents were separated and identified by gas chromatography-mass spectrometry (GC-MS). The relative contents were determined by area normalization.RESULTSThe extraction rate of the bark of Horsfieldia hainanensis was 0.14%. 32 compounds were separated and identified, which accounted for 98.62% of the essential oil. The main chemical components of the essential oil were Copaene (25.55%), Naphthalene, 1,2,3,5,6,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-(11.14%), Hexanedioic acid, bis(2-ethylhexyl) ester (8.09%) , 9-Octadecenoic acid (7.04%), etc.CONCLUSIONIt has provided scientific foundation for exploitation and utilization of Horsfieldia hainanensis.

The floristics of seed plants in coastal hilly areas of southern Hainan Island was studied on the basis of data of 6 600 m2 sampling plots and route survey.There were 876 species,belonging to 484 genera and 112 families.There were 78 families of Tropical elements,accounting for 69.64% of the total families.The Tropical elements at genus level were the dominant components,in which the Pantropic genera and Tropical Asian genera contributed 33.47% and 19.62% of the total(excluding cosmopolitan),respectively.There were 3 genera endemic to China,e.g.Merrillanthus,Hainania and Chunechites.At the species level,Tropical elements contributed 74.94% of the total number of species(excluding cosmopolitan).There were 204 species endemic to China,accounting for 23.13% of the total species,in which 78 species were endemic to Hainan.Compared with the seed plant flora in the northern Island,it had obvious differences in species composition,due to differences in natural landform and climate.

Antiaris toxicaria,an endangered tree species grew mainly around the natural villages in Haikou Aera.Our objectives were to explore the effects of human activity on the quantitative characteristics and distribution pattern of A.toxicaria population.We placed 6 sample plots in Haikou and studied the quantitative characteristics and distribution pattern of A.toxicaria population including size structure,static life table,survival curve,distribution pattern and its dynamics.The results showed that: ①The seed bourgeon rate was high,seedling was abundant,the young tree lacked,the single was abundant at the middle age,the single lacked at the old age.The spindle-shaped size class structure indicated that the populations of A.toxicaria were declining;②The mortality of size classes Ⅱ and Ⅲ was negative,indicating a shortage of size class Ⅱ and Ⅲ individuals.The peaks of mortality at size classes Ⅵ was caused for approaching the species' longevity;③Although its' seed survival rate was relatively high,its young tree survival rate was low,its survival curve was close to Deevey Ⅲ type;but without the artifical disturbance effect in the young tree period,the survivorship curves of A.toxicaria populations generally follow Deevey Ⅰ Type.It assumed convexity.The habitat of the Haikou was suitable for the growth of A.toxicaria;④The spatial distribution pattern tended to be clumped,which was accordant to most rare plant community;the artificial disturbance and natural environment affected its disturbance pattern,which made the community turn into the random distribution from assemble distribution,and then developed to the assemble distribution.

Shanlan upland rice is one of major types of upland rice,which is of important social,ecosystem and economic value.The present paper reviewed the achievements of research on Shanlan upland rice in China including germplasm,agronomic traits,drought resistance,genetic basis and breeding.The problems were also discussed and some suggestions were put forward.

Based on the grasped materials and the investigation,it is found that there are 131 species of medicina plants belonging to 62 families.It concludes 2 species 2 families of pteridophyta,1 species 1 families of gymnosperm,and 128 species 59 families of angiosperm in Damao village of Sanya city.They are classified into 13 groups by medicinal parts,such as root,leaf,fruit,tegument,bloom and so on,and 16 groups by medicine function and main effect,such as diaphoretic,antipyretic and eliminate and so on.Then analyzed the distribution characteristics of resources of medicinal plants,and the suggestions of protection and exploration are put forward.

The article reviews the present research situation of the psammophilous vegetation on coasts in china from six respects,including the distribution,habitats,composition,succession,adaptability and function.

The biological characteristics of E.odoratum were reviewed as well as its damage and prevention,the development and utilization,the problems in E.odoratum and other aspects.Research suggestions in future were put forward.