whitbread, worbes & kühne ws 2011/12

Crops and production systems in the Tropics

Whitbread, Worbes & Kühne

WS 2011/12

Worbes & Kühne, Crops & Production System: Climate

Climate and plant growth in the tropics

1. Climate

1. Introduction2. Describing the climate by diagrams

3. Trends of precipitation patterns

4. Seasonality of rainfall in the tropics

5. Defining climate types

6. Agro-Ecological Zones

7. Climate anomalies: El Nino and La Nina• Mechanisms of Southern Oscillation Effect

• Reconstruction of El Nino with tree rings

• Reconstruction of El Nino with Ice cores

8. Global change

How do organize a lecture on Tropical Crop production Sytems

• By Crop Species (taxonomically)

Scientific classification (binomial nomenclature, Carl v. Linné, 1707–1778)

Coconut Palm (Cocos nucifera)

Kingdom: PlantaeDivision: Magnoliophyta (form. Angiosperms)

Class: Liliopsida (form. Monocotyledonae) Order: Arecales

Family: Arecaceae (form. Palmae) Genus:Cocos

Species: nucifera L.

http://upload.wikimedia.org/wikipedia/commons/7/7a/1859-Martinique.web.jpg



• By Products (consumer orientated)

http://www.uni- goettingen.de/en/publications/

209930.html(Rehm_Espig

zip)

Main Crops in the Tropics

Purpose Crop Main Region Main Country/Tropics Production (main country in Mill. Mt)

Staple FoodRice SEA India 130Roots and Tubers Africa/Asia Nigeria 60Maize Latin America Brazil 34

Cash CropsSoy beans Latin America Brazil 50Sugar cane LA/Asia Brazil 420Coffee LA/Asia Brazil/Vietnam 2/1Coconuts SEA Indonesia/Phillipines 16/14Cacoa Africa ivory Coast 1Bananas SEA/LA India 17Palmoil SEA Malaysia/Indonesia 14/12Citrus many countries



• By Products (consumer orientated)

• By Production system (producer orientated)

Introduction into Tropical Agronomy

Crops and production systems in the tropics

Source: United Nations University project on Climatic, Biotic, and Human Interactions in the Humid Tropics

Farmingsystem

Traditional system

Semi-commercial

system

Commercial system

Shiftingcultivation,small

holders

Nomadicherding

Rice, legume, root cropped

based

Agrofor. Fruitproduction

Annual Crops Perennial cropsAgroforestry

Rice, sugarcane, maize Cacao, coffee

Bericht Weltagrarrat 2008International Assessment of Agricultural Knowledge, Science andTechnology for Development (IAASTD)

Introduction into Tropical Agronomy

Frame conditions of tropical agriculture

• Ecology

– Wide range of climates from desert to superhumid

– Wide range of soil fertility: sometimes poor

– High diversity of crops

• Socio-Economic

– Subsistence agriculture

– Big scale commercial farming for cash crops



1. Climate1. Introduction

2. Describing the climate by diagrams3. Trends of precipitation patterns







8. Global change


Geographic

Tropics 23.5o N to 23.5o S

38% of land surface,

(half the global surface)

day length 10.5-13.5 hrs

Subtropics to 45o N and S

24% of land surface

day length 9-15 hrs

Climatic

Tropics < 5o difference in mean monthly temperatures.

area between the 18o isotherms at sea level.

but temperature drops 0.6o per 100m elevation

daily temperature variation > variation of monthly means

Subtropics mean monthly temperature > 9.5o for at least 8 months

climatic characteristics:

trade winds, Monsoon, Moisture regimes:

perhumid > 10 months, subhumid, semiarid < 7 months

Definitions of Tropics and Subtropics


Climate at the border between tropics and subtropics

Climate in Piracicaba, Sao Paulo, Brazil and T in Goettingen, Germany

0

50

100

150

200

250

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Prec

ipita

tion

0

5

10

15

20

25

30

T

Pira PrecPira TGoett T



1. Climate

1. Introduction

2. Describing the climate by diagrams3. Trends of precipitation patterns






7. Global change



Convention of the Walter and Lieth Diagramms

Daily temperature

variations

Precipitation

Annual

means

Temperature

Climate

station

information

Perhumid

Humid

Arid

Maximum/Minimum

Humidity

index


Superwet = perhumid wet = humid

Tropical climate types

Following Walter & Lieth in Richards1996


seasonal

wet Dry-

arid

Tropical climate types cont.


Distinction between Arid and Humid

• Humid: potential evapotranspiration is lower than precipitation

• Arid: potential evapotranspiration is higher than precipitation



1. Climate1. Describing the climate by diagrams

2. Trends of precipitation patterns3. Seasonality of rainfall in the tropics






7. Global change


Lauer 1989

Trend I: decreasing precipitation towards the tropics


Trend II: Precipitation increases over land masses from east to west


Trend III: increasing precipitation with elevation

Sierra de Lema

0

100

200

300

400

500

600

J F M A M J J A S O N D

Prec

ip. (

mm

)

km 88

0

100

200

300

400

500

600


Prec

ip (m

m)

Anacoco

0

100

200

300

400

500

600


Wind direction

Sierra de Lema(1000 m AASL)

Km 88Anacoco(lowland)

150 km

1550 mm 2970 mm 4770 mm


Reason for increasing precipitation with elevation

1.) Temperature decrease: -0.65 0C per 100 m2.) Decreasing dew point with decreasing T

Worbes & Kühne, Crops & Production System: ClimateLauer 1989

Global Radiation





3. Seasonality of rainfall in the tropics4. Defining climate types





7. Global change


The intertropical convergence zone (ITCZ)

Hadley-cell

The intertropical

convergence

zone

(ITCZ) is

a dynamic weather

area

located

near

the equator. Sunlight

at the equator

warms

the air, making

it

rise

and thereby

creating

low

pressure at the equator, along

with

rain-producing

cumulonimbus

clouds.

The rising

air eventually

cools

and sinks

back to the surface

at latitudes

roughly

30Â°

north

and south

of the equator. The

sinking

cool air creates

high-pressure

systems that

keep

those latitudes

relatively

dry. The sinking

air is

drawn

back to the low

pressure

near

the equator, creating

a flow

of air known

as the trade

winds


But the position of the hadley cells relative to earth‘s surface are not stable, they are moving during the years course:

Why?


Seasons in the tropics as consequence of the position of the sun


• However: The wind circulation of the hadley cells is not north-south or south-north

• But tends to be east-west (trade winds)


Climate types in the tropics


Distribution of climate types in the tropics


Concept of Growing Period

The

saisonality

of tropical climates

is

regarded!

http://www.fao.org/


Some Conclusions

Seasonal tropical climate is

based

on variation

in precipitation

Seasonal

climate

occurs

in most

areas

of the

tropics Precipitation

pattern

is

influenced

by

the

geographic

and

orographic

situation






4. Defining climate types5. Agro-Ecological Zones




7. Global change


The KÖPPEN climate classification

is of the most widely used climate classification systems.

• Developed by Wladimir Köppen, a German climatologist, around 1900 (modifications by

himself, in 1918 and 1936).

• Based on the concept that native vegetation is the best expression of climate, thus

climate zone boundaries have been selected with vegetation distribution in mind.

• It combines average annual and monthly temperatures and precipitation, and the

seasonality of precipitation


Wladimir Köppen divided the Earth’s surface into climatic regions that generally coincided with world patterns of vegetation and soils.

The Köppen system recognizes five major climate types based on the

annual and monthly average of temperature and precipitation. Each type is designated by a capital letter.

A – Moist Tropical Climates are known for their high temperatures year

round and for their large amount of year round rain. B – Dry Climates are characterized by little rain and a huge daily

temperature range. Two subgroups, S – semiarid or steppe, and W – arid or desert, are used with the B climates.

C – In Humid Middle Latitude Climates land/water differences play a

large part. These climates have warm, dry summers and cool, wet winters.

D – Continental Climates can be found in the interior regions of large

land masses. Total precipitation is not very high and seasonal temperatures vary widely.

E – Cold Climates describe this climate type perfectly. These climates are

part of areas where permanent ice and tundra are always present. Only about four months of the year have above freezing temperatures.

The Köppen Climate System


Köppen Subgroups are designated by a second, lower case letter which distinguish specific seasonal characteristics of temperature and precipitation.

f – Moist with adequate precipitation in all months and no dry

season. This letter usually accompanies the A, C, and D climates.

m – Rainforest climate in spite of short, dry season in monsoon

type cycle. This letter only applies to A climates. s – There is a dry season in the summer of the respective

hemisphere (high-sun season). w – There is a dry season in the winter of the respective

hemisphere (low-sun season).

The Köppen Climate System II


Vegetation types in the Tropics


Lowland

forest

types

in moisture

gradient

ILowland

forest

types

in moisture

gradient

I

EcosystemEcosystem Dominating “climate“ factorDominating “climate“ factor

Diurnal flooding

Annual flooding

Precipitation


Lowland

forest

types

in a moisture

gradient

IILowland

forest

types

in a moisture

gradient

II

EcosystemEcosystem Climate typeClimate type


Altitudinal

gradientAltitudinal

gradient

EcosystemEcosystem Climate TypeClimate Type

3200-4600mT = 10-1 0C

Espeletia

Paramo

Mountain

cloud

forest

1000-2100mT = 21-14 0C

Mountain

dry

forest

Holdrige

Triangle: Life zone

spectrum

HUMIDITY PROVINCES wikipedia


Conclusion:

Long term

means

of climate

conditions

are

linked with

natural

vegetation

The

climate

type

determins

the

vegetation

type

and the

frame

conditions

for

agricultural

cropsLecture

notes

on:

http://www.uni-goettingen.de/en/306338.html







5. Agro-Ecological Zones6. Climate anomalies: El Nino and La Nina

• Mechanisms of Southern Oscillation Effect



7. Global change


Jan

Feb Mär Apr Mai Jun

Jul

Aug Sep Okt Nov Dez Monat

0

20

40

60

80

100

300

Niederschlag [mm]

200

400 nda La Pacifica/Finca Las Pumas (45 m) 26,6° C 1403 mm

960 11/2001)

Pineapple, Banana,Papaya, Palmito

K

Coffee and ornamental plants

Cattle, Rice, Sugar Cane

Predominant farming systems for different ecoregions in the humid tropics

Ecoregion* Rainfall* (mm/yr) Farming systems

Lowland

Moist forest 1500-2000 Root crops (yam. Cassava, sweet potatoe), rice

Wet forest 2000-4000 Plantations (e.g. Bananas, plantain, citrus)

Rainforest > 4000 Tree crops (e.g. rubber, cocoa, oil palm)

Pre-montane (-800)

Moist forest 1000-2000 Root crops, upland rice, beans

Wet forest 2000-4000 Coffee, tea, pineapple. cocoa

Rainforest > 4000 Timber crops and tree plantations

Lower montane (-1500)

Moist forest 500-1000 Sub-tropical vegetable, root crops

Wet forest 1000-2000 Coffee, Tea, cash crops

Rainforest > 2000 Tree crops


Concept of Growing Period

The

saisonality

of tropical climates

is

regarded!

http://www.fao.org/











7. Global change


What

is

an El Nino•

The

El-Niño

Southern Oscillation

is

the

result

of a cyclic

warming

and cooling

of the

surface

ocean

of the

central

and eastern

Pacific.•

It`s

intensity

is

measured

through

indices: 1.) SST: Sea

Surface

Temperature2.) The

difference

between

sea

level

pressure

at Darwin and Tahiti.


Normal conditions:•

Water hot in West (28 degrees) and cooler in East Pacific (24 C0)

•

Wet

in West-Pacific•

Cool water

of the

deep

sea

rises

in east


El Nino conditions:•

Hot in the

center

•

Wet

in East-Pacific•

Warm water

prevents

the

deep-sea

water

to rise

to the

surface


La-niña

conditions

•

When

the

injection

of cold

water

becomes

more

intense than

usual, causing

the

surface

of the

eastern

Pacific to

cool -

this

is

a LA-NIÑA event.


Typical conditions

www.elnino.info


El-Nino conditions

www.elnino.info


http://www.ucar.edu/communications/factsheets/elnino/

ENSO-Effect on Precipitation: El Nino

ENSO-Effect on Precipitation: El Nino


ENSO-Indices – Southern Oscillation Index (SOI)

Normalized pressure differences between Darwin and Tahiti

Ropelewski & Jones (1987)

Climatic Research Unit, University of East Anglia, Norwich NR4 7TJ, UK

Data since 1866


Thompson et al. 1995


Ice core

-1

-0,5

0

0,5

1

1,5

1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990year

Ice

core

laye

r ind

ex

Ice core

,,,,

Index curves of Piranhea tree rings and ice core layer thickness

Ice core data from Thompson et al. 1995, Science

The Java Teak-Chronology from Berlage (1931)The Java Teak-Chronology from Berlage (1931)

In: Jacoby (1989)


0

100

200

1800 1850 1900 1950 2000

indi

ces

calibrationreconstruction

0

100

200

1900 1920 1940 1960 1980 2000

indi

ces

n = 10 r = 0.60 Glk% = 73 T-Value = 6.2

Index ring width of Piranhea trifoliata (black) floodfree period of the Amazon river (blue) and El Nino years (red triangles)

Index ring width of Piranhea trifoliata (black) floodfree period of the Amazon river (blue) and El Nino years (red triangles)


El Nino Effects

•

Change of temperature

and air

pressure

in the

southern

pacific•

Consequences:–

Change in precipitation

(some

regions

with

more

some

with

less

rainfall

–

Change of sea

current

system

in the

pacific

(interruption

of the Humboldt current)

–

Less

nutrient

rich

and cold

water

at the

South American coast–

Less

plankton, less

fishes, decline

in fishery

in Peru around

Christmas


The circumpolare wave as an explanation for the El Nino frequency

Warm water

cold

water

whitbread, worbes & kühne ws 2011/12

Documents