The Geography project

To study how climatic conditions affecting the types of vegetation in the arid and humid regions

The name lists

Ho Kin Tao (Chris) (3)

Leung Pak Hei (Marco) (5)

Kwan Pak Yan (Zoe) (25)

Tang Cheuk Yiu (Yoyo) (28)

Yuen Sau Yan (Eliza) (35)

Climate condition of arid region

An arid climate also called desert climate and in which precipitation is too low to sustain any vegetation at all, or at most a very scanty scrub.

Severe lack of rainwater and  moisture less than 250 mm (10 inches) per year of precipitation in some years may experience no precipitation at all. an area may experience more than 250 mm of precipitation annually, but is

considered an arid climate because the region loses more water via evapotranspiration than falls as precipitation

Desert climate (arid climate) can be divided into hot desert climate and cold desert climate

Hot desert climates are typically found under the subtropical ridge where there is largely unbroken sunshine for the whole year due to the stable descending air and high pressure. Such areas include the Sahara Desert, Northern Mexico, and much of Australia. These areas are located between 30 degrees south and 30 north latitude Hot desert climates are globally hot, sunny and dry year-round.

Climate condition of arid region

Hot desert climates feature hot and dry. In many locations featuring a hot desert climate, maximum temperatures of 40 °C (104 °F) to 45 °C (113 °F) are common in summer. During colder periods of the year, night-time temperatures can drop to freezing or below due to the exceptional radiation loss under the clear skies.

Cold desert climates can feature hot , dry summers, and cold winter , sometimes brutally cold, dry winters with temperatures far below the freezing point. Cold deserts are typically found at higher altitudes than hot desert climates, and are usually drier than hot desert climates.

A cold desert climate is typically found in temperate zones, almost always in the rain shadow of high mountains which restrict precipitation from the westerly winds, or in the case of Central Asia, from the monsoon. e.g the Gobi desert.

Location of Arid region

Climate condition of humid region

Humid climate are characterized by a warm and wet climate. Rainfall is heavy in all months. The total annual rainfall is often more

than 250 cm. (100 in.). There are seasonal differences in monthly rainfall but temperatures of 27°C (80°F) mostly stay the same. Humidity is between 77 and 88%.

High surface heat and humidity cause cumulus clouds to form early in the afternoons almost every day.

The climate on eastern sides of continents are influenced by maritime tropical air masses. These air masses flow out from the moist western sides of oceanic high-pressure cells, and bring lots of summer rainfall. The summers are warm and very humid. It also rains a lot in the winter Average temperature: 18 °C (°F) Annual Precipitation: 262 cm. (103 in.) Latitude Range: 10° S to 25 ° N Humidity is between 77 and 88%. Global Position: Amazon Basin; Congo Basin of equatorial Africa;

East Indies, from Sumatra to New Guinea.

Location of humid region

Major characteristics of vegetation in arid region

Arid Region Trunk and stem: thick Leave : most of them have small and with needle-

shaped (Cactus) Some plants develop a waxy resin Root : long and in the deep part of the soil,

widespread. e.g. Echinocactus grusonii (Golden Ball Cactus),

Opuntia tuna, Haworthia bolusii.

Dry Plant

Dry Plant

Major characteristics of vegetation in humid region

Humid Region Evergreen Trunk : thick, some of them have tall trunk. Leave : board and with drip-tip, some of them have

wax on their surface. Root : some of them have shallow and buttress root. e.g. Dieffenbachia picta (Dieffenbachia), Asparagus

falcatus, Codiaeum variegatum (Garden Croton) .

Humid Plant

Humid Plant

How the characteristics of vegetation are related to the climatic condition in arid region?

Climate condition of the arid region Major characteristics of vegetation in arid region

Extremely dry (annual rainfall less than 250mm)

High evaporation rate

Due to lack of water and high evaporation rate:Some plants have shallow roots, they spread over a wide area. The roots of plants which have a tap root system can go as deep as 30 meters under the surface of the earth to draw water.

Some plants adapt their leaves in such a way that they become needle-shaped, which reduces the surface area of leaves exposed to the sun so as to curb evaporation. Some plants develop a waxy resin  which help in minimizing water evaporation. Thick truck and stem (e.g. cactus) used for storing water. 

How the characteristics of vegetation are related to the climate condition in humid region?

Climate condition of the humid region Major characteristics of vegetation in humid region

Hot and wet throughout the year Evergreen

High annual amount of rainfall Plants grow luxuriantly and continuously under the continuous hot and wet climate

Rich diversity of plant species (hot and humid climate results in rich diversity of plant species

Trees have shallow roots (able to nutrients up from the topsoil)

Trees have buttress roots (provide strong support for the tall trees)

Broad , waxy leaves with drip tips help shed excess water from leaves.

Visit to the Foregate Conservatory of the Hong Kong Park (Dry Plant House)

Visit to the Foregate Conservatory of the Hong Kong Park (Humid Plant House)

~The End~