Question

Which plant group or subgroup is the most prominent in each ecozone and how does this relate to the features of each ecozone?

Answer 1

.Ans . The ecozones are also called as biogeographic realms.There are eight ecozone along with plant groups namely:-

(1) Nearctic realm -They constitute broadleaf forest ( oaks, beeches, maples or birches)and mixed coniferous forest (Pines, firs and spruces).These kind of forest occur in this ecozone because of warm and cool climate.Temprature is between 3 -15 C

(2) Palaearctic realm-They mostly consist of sclerophyll plants like proteacea, tea tress, acasia, boronias and eucalypts due to the hot and dry climate and lot of fire use.Pine, oak and walnut woodlands are also present.

(3) Africotropical realm - they consist of deserts and woodlands.Also Sahel and sudan belts.Sahel is dominated by grass Cenchrus biflorus, Schoenefeldia gracilis and Aristida stipoides.Other tree species include Commiphora africana, Balanites aegyptiaca, Faidherbia albida, and Boscia senegalensis. In the northern part of the Sahel, areas of desert shrub, including Panicum turgidum and Aristida sieberana, alternate with areas of grassland and savanna.

(4) Indomalayan realm- It is surrounded by tropical and subtropical broadleaf forest and consist of tress of diptocrp family

(5) Oceanian realm- they consist of rainforest and Desert or semi-arid land commonly known as the outback makes up by far the largest portion of land.Flora include Proteaceae (Banksia), Myrtaceae (Eucalyptus – gum trees), Fabaceae (Acacia – wattle) ,palm trees, premna protrusa, psydrax odorata, gyrocarpus americanus and derris trifoliata..

(6) Australian realm-The climate is too cold with little rainfall and little sunlight, so no vascular plants can grow.They share flora of antartica which consists of conifer Cupressinoxylon,Podocarpoxylon.The angiosperm component includes two species of Nothofagoxylon, one species of Myrceugenelloxylon , and one species of Weinmannioxylon.

(7) Antarctic realm- same as above.

(8) Neotropical realm-These regions are humid all time of the year and so are mostly covered by tropical rainforest which require ample amount of rainfall.There are small number of very large trees, called emergents, which grow above the general canopy, reaching heights of 45–55 m, although on occasion a few species will grow to 70–80 m tall.Some examples of emergents include: Balizia elegans, Dipteryx panamensis, Hieronyma alchorneoides, Hymenolobium mesoamericanum, Lecythis ampla and Terminalia oblonga .