N

Spatial Variation of Vegetation in the TVC

How do we explain why vegetation is found where it is in TVC?

S oil

C limate

A ltitude

R elief

E ruptions (history)

S tage of succession (or climax)

Boulder/Gravel Fields

• Can be covered in snow and ice

• Little/no vegetation

• Too cold and windy for anything to grow

N

Gravel Field

Gravel Field

Gravel Field

Gravel Fields

Soil: No soils at the tops of the mountains because high winds mean no soil can stay permanently, also there is no vegetation to help create the soil as it is too cold for plants HOWEVER, there are Azonal soils on the Rangipo Desert – these are infertile and the winds blow away any vegetation that tries to grow there.

Climate: Extreme cold and extreme winds, high levels of rainfall on the western side, but not very much rain on the eastern side

Gravel Fields

Gravel Fields

Altitude: 2797m at the top of Mt Ruapehu to 1000m at Rangipo Desert

Gravel Fields

Relief: steep at the tops of the mountains BUT flat in the Rangipo desert

Gravel Fields

Eruption History: this area is most susceptible to the effects of eruptions because the mountain tops are closest to the vents. The gravel fields on the eastern side of Mt Ruapehu are highly susceptible to the ash fall from its most recent eruptions (2006) due to prevailing westerly winds which direct the ash over the Rangipo Desert gravel fields Less concentrated).

Gravel Fields

Stage: At the top of the mountains it is at vegetation climax because plants can not grow in these conditions HOWEVER, on the Rangipo Desert it is at stage 1 of vegetation succession because technically the altitude should allow growth of vegetation up to Beech Forest.

Tussock

N

Tussock on Rangipo Desert

Tussock on the Rangipo Desert

Soils: Azonal soils – very infertile because they are “young” soils

Tussock on the Rangipo Desert

Climate: Cold wind funnels through the Tama saddle, tearing up plants and soil. Less rainfall because of the rain shadow effect caused by the three mountains. 1500mm of rainfall per year = plants find it harder to grow there

Tussock on the Rangipo Desert

Altitude: 1100m high

Tussock on the Rangipo Desert

Relief: Flat – is a part of the ring plain around the volcanoes

Tussock on the Rangipo Desert

Eruption History:

Lake Taupo erupted 1800 years ago and wiped out the beech forest that used to be there. Subsequent eruptions constantly cover the area in ash due to the prevailing westerly wind

Tussock on the Rangipo Desert

Stage: 2nd stage of vegetation succession. (climax here would be beech forest)

Tussock on the Eastern Foothills

Climate: Cold, windy, high levels of rainfall due to the orographic rainfall effect = 1400mm per year on the Eastern side of TVC

Tussock on the Eastern Foothills

Eruption History: The hot spot was once under Mt Tongariro and Mt Ngauruhoe which has made them highly active in the past. They last erupted in the 1970s, which has meant there has been 40 years of regeneration.

Scrub

• Kanuka and Manuka, New beech forest (young)

N

tries

Scrub

North Eastern Manuka & Kanuka forest with new beech forest

Soils: Tongariro ash soils and fine textured loam which are highly fertile. The lower levels of rainfall on the eastern side, have meant that these soils do not get leached, which has meant that the vegetation regeneration process has been faster on the eastern side than the western side.

North Eastern Manuka & Kanuka forest with new beech forest

Climate: Cold, rainfall – 1048mm per year due to rain shadow effect of Mt Tongariro and Mt Ngaruhoe. Not as windy as Rangipo desert however, so plants find it a bit easier to grow

North Eastern Manuka & Kanuka forest with new beech forest

Altitude: 900-1200m high

North Eastern Manuka & Kanuka forest with new beech forest

Relief: low rolling land which means that the high winds have less of an effect on the vegetation and the soils.

North Eastern Manuka & Kanuka forest with new beech forest

Eruption History: Hot spot has moved so Mt Tongariro & Ngaruhoe have become less active since 1974. This means vegetation has been able to slowly regenerate.

North Eastern Manuka & Kanuka forest with new beech forest

Stage: Stage 3 of vegetation succession for most of this area, however the pockets of beech forest are at vegetation climax.

Beech Forest

• More open than podocarp forest

• Can handle colder climates

N

SW Beech Forest

Soils: Tongariro Ash soils which are very fertile, providing plenty of nutrients to support large trees

SW Beech Forest

Climate: Cold, high levels of rainfall due orographic rainfall effect – 2800mm of rain per year

SW Beech Forest

Altitude: 1000-1300m elevation

SW Beech Forest

Relief: rolling hills enables trees to grow well (because it is not steep)

SW Beech Forest

Eruption History: Lake Taupo’s eruption wiped out the beech forest, but it was able to grow back because the climate is less volatile than on the eastern side.

SW Beech Forest

Stage: 3rd stage of vegetation succession = vegetation climax for this altitude

Podocarp Forest• Dense,

green, mixed forest

• Found in the South West Quadrant of TVC

Podocarp Forest

Soil: Tongariro ash soil and fine textured loam; Well developed, rich in nutrients to support forest growth

Podocarp Forest

Climate: High levels of rainfall (2800mm per year) due to it’s location on the SW slopes and the effect of orographic rainfall from the prevailing SW weather. Wind is low, allowing tall trees to grow

Podocarp Forest

Altitude: Extends to a maximum of 1000m, after which beech forest becomes dominant.

Podocarp Forest

Relief: low rolling land which means that winds have less of an effect on the vegetation and the soils.

Podocarp Forest

Eruption History: Taupo eruption 1800 year ago wiped out most of the forest, however due to the prevailing SW wind this forest is relatively protected from ash fall

Podocarp Forest

Stage: climax reached. An abundance of birds and animals help podocarp to spread quickly by carrying seeds

WHAT is the Vegetation

WHERE is it found in TVC?

WHY Does it exists there? (Think S.C.A.R.E.S)

Specific detail (plant types?)

None / lichens & moss

Tussock

Shrubland

Beech Forest

Podcarp Forest

WHAT is the Vegetation

WHERE is it found in TVC?

WHY Does it exists there? (Think S.C.A.R.E.S)

Specific detail (plant types?)

None / lichens & moss

The peaks and upper slopes of T, N, and R; extending to lower altitudes on the East (______m)

Tussock On the Western of Mt T, N & R and also on the eastern foothills between Mt Ngaruhoe and Mt Ruapehu.

Shrubland Native Manuka and Kanuka, introduced Heather

Beech Forest

Podcarp Forest

Rich Tongaririo Ash soil, high rainfall, and protection from wind