Copyright 2010 Research Institute for Humanity and Nature. All Rights Reserved. What will happen when biodiversity degrades? The Futurability of Biodiversity

Copyright 2010 Research Institute for Humanity and Nature. All Rights Reserved.

What will happen when biodiversity degrades?

The Futurability of Biodiversity Chapter 5



In review

Biodiversity means...

Various kinds of organisms (genetic variation and species richness) have evolved through a range of interactions (a diversity of interspecific interactions), and as a whole, a diversity of ecosystems has been formed.


Today’s Topics

1. Effects of extinction of a species1. Effects of extinction of a species

2. Effects of changes in biota2. Effects of changes in biota

3. Effects of changes in landscapes

What will happen when a species is eradicated?

What will happen when biota change?

What will happen when landscapes change?

4. The relationships between biodiversity and livestock

How do livestock affect plant diversity in grassland?


What will happen when a species is eradicated?

1) Food web

2) Species evolution

3) Seed dispersal

1. Effects of extinction of a species


1. Effects of extinction of a species 1) Food web

Food web in Canadian forestNorthern harrier

Goshawk

Golden eagle Great-horned owl

Lynx Coyote

Red fox

Wolf

Passerine birds

Spruce grouse

Snowshoe hareGround

squirrel

Red squirrel

Small rodents

InsectsFungi

Grasses Bog birch Grey willowWhite

spruce

Balsam poplar

(revised Krebs et al. 2001)

Willow ptarmigan



Simplification of food web




Increase?

Influence on the species which did not have direct interaction



Possibility of changes in evolutionary direction

Cirsium amplexifolium var. muraii

Cirsium amplexifolium Population density of Japanese deer in Kinkazan is very high.

Evolution against grazing by deer

Photo: A. Emanon Photo: A. EmanonPhoto: Masashi Igari

1. Effects of extinction of a species 2) Species evolution


1. Effects of extinction of a species 3) Seed dispersal

Plants which bear large seeds rely on large animals for their seed dispersal.

Indian elephant Great hornbill

Finlayson’s Squirrel

Orange-bellied Flowerpecker

Photo: Shumpei Kitamura


1. Effects of extinction of a species 3) Seed dispersal

Population of large primate(small → large)

Population and species richness of seedlings which bear large seeds decreases.(revised Chapman & Onderdonk 1998)

Population of flying fox (small → large)

The number of fruits which are eaten decreases.(revised McConkey & Drake 2006)

Con

sum

ptio

n ra

tio o

f fr

uits

（%

）

Den

sity

of

seed

ing

(m-2)

Num

ber

of s

eedl

ing

spec

ies

(●)

In a forest where the number of large animals decreases…


Food web becomes simpler even if only one species within

the food web is eradicated, and the extinction sometimes

affects the population dynamic of the species which did not

have direct interaction with the one eradicated.

In cases where a plant and an animal continue to evolve

through an arm’s race, if the plant species is eradicated, the

evolutionary direction of the animal species may change.

Plants which bear large seeds fail to spread their seeds if a

large animal species is eradicated.

Summary 1. Effects of extinction of a species


What will happen when biota change?

1) Changes in components of ecosystems

2) Number of useful species

3) Stability of ecosystem

2. Effects of changes in biota


Secondary forest

Plantation forest (Cedar forest)

Conversion from secondary forest to monoculture plantation

2. Effects of changes in biota 1) Changes in components of ecosystems


A large amount but only one resource can be taken.

A small amount but various kind of resources can be taken.

Biota are drastically changed by tree-planting

Secondary forest Monoculture plantation

2. Effects of changes in biota 1) Changes in components of ecosystems


2. Effects of changes in biota 2) Number of useful species

(Nagaike et al. unpublished data ）

Changes in the number of plant species

The number of herbaceous plant species in a forest


Plantation forests are intolerant against strong winds.Forests devastated by wind are intolerant against other natural disasters such as floods or landslides.

Plantation forest blown down by typhoon (left: sakhalin fir, right: cedar)

Changes in tolerance against natural disasters

Photo: (left) National institute for Environmental Studies (right) Keizou Hirai

2. Effects of changes in biota 3) Stability of ecosystem



Changes in tolerance against infectious disease

Carps (Cyprinus carpio carpio) killed by Koi herpes virus. Photo: Masatomi Matsuoka



Physical factors which affect incidence rate:waterside environment

Concrete wall … Incidence rate is high.

Various plants grow.… Incidence rate is low.

Photo: Hiroki Yamanaka



Diversity is high…incidence rate is low.

Diversity is low …incidence rate is high.

Biological factors which affect incidence rate:diversity of fish species


Various numbers of plant species were planted in a grassland, and their standing crops were measured at the end of growth periods. Figures in the graph indicate the experimental years. (Tilman et al. 2002)

Standing crop （ g m-2 ）

The relationships between plant diversity and productivity

Difference in standing crops of three research plots whose numbers of plant species are different. Standing crops were also measured at the end of growth periods.

(Bezemer & van der Putten 2007 ）

(1)

Productivity is lowest where species richness is high.

2. Effects of changes in biota 4) Fauna and productivity

The more the number of species increases, the higher productivity is.

(2) (3)


Summary 2. Effects of changes in biota

When biota of an ecosystem changes, availability of

natural resources in the ecosystem also changes.

The stability of an ecosystem tends to be greater in

those whose species diversity is high.

Biodiversity enhances many ecosystem functions,

though the effects are uncertain.


What will happen when landscapes change?

1) Genetic variation

2) Risk of extinction

3) Combination of ecosystems

3. Effects of changes in landscapes


3. Effects of changes in landscapes 1) Genetic variation

Changes in landscape due to development

Primary forest (hilly land)

Swamp forest

Secondary forest

Rice field

Logging forest

0 10 km

Change in land use around Lambir Hills National Park, Borneo, Malaysia

1963 1997


Demographical fluctuation

Environmental fluctuation

Restricting individual migration between populations

Degradation of genetic variation

Expression of deleterious gene

Extinction of local population

Decrease of population

Fragmentation / Isolation of habitat



Floridian Panther

X-ray of tail

Floridian Panther whose genetic variation is low

Crossbreeding of Texan individual whose genes are different

Disappearance of genetic disease

Importance of genetic diversity

Expression of recessive deleterious gene　 - Decline in quality of sperm　 - Deformity of tail　 - Back-combed hair

Improvement of genetic variation

(Hedrick 2001)



Decline in genetic variation


Distance between forests (km)

Continuous forests

Fragmented forests

(Jump and Peñuelas 2006)

Ge

net

ic d

iffe

ren

tiatio

n

bet

we

en

fore

sts

Genetic differentiation of European beech forest


Loca

l ext

inct

ion

prob

abili

ty o

f po

pula

tions

dur

ing

100

year

s (%

)

Habitat area of population (km2)

（ revised Agetsuma 2007 ）

In the case of Japanese monkey (Macaca fuscata), the smaller their habitat area is, the greater the possibility of local extinction is.

3. Effects of changes in landscapes 2) Risk of extinction

Local extinction due to reduction of habitat


Local extinction due to loss of indispensable environment

Rhacophorus schlegelii arborea

Habitat of adults

Habitat of tadpoles

Habitat of tadpoles

Photo: Echigo-Matsunoyama Museum of Natural Science, ‘Kyororo’

3. Effects of changes in landscapes 3) Combination of ecosystems


Summary 3. Effects of changes in landscapes

Local populations decline because of degrading

genetic variation.

Probability of accidental extinctions increases due

to demographical and environmental fluctuations.　

Species which need several kinds of habitats to live

will be eradicated even if only one such habitat

disappears.


How do livestock affect plant diversity in grasslands?

1) Grazing’s effects on grasslands

2) Species diversity in grasslands

4. The relationships between biodiversity and livestock


4. The relationships between biodiversity and livestock 1) Grazing’s effects on grasslands

Mongolian pasturage - Grasses makes livestock fat, and then humans can obtain nutrition from livestock in the form of meat, milk and dairy products.

(See Chapter 7 in detail.)


4. The relationships between biodiversity and livestock 1) Grazing’s effects on grasslands

Grazing by livestock

Livestock usually eat grasses above ground only.…Grasses are heavily damaged but their roots and apical meristem remain.

Livestock supply nutrients for grasses as dung.…Grasses can regrow using these nutrients.


4. The relationships between biodiversity and livestock 2) Species diversity in grasslands

Species richness of pasture plants

Number of species is highest where grazing pressure is intermediate.

(Fujita 2006)



(Fujita et al. 2009)

Ridge

Stream

Near ridge

Upper slope

Lower slope

Foot slope Valley bottom

Soil moisture

Low Low Intermediate Intermediate High

Species richness according to resource availability

Spe

cies

ric

hnes

s (/

m2 )

Grazing effects on species richness vary according to topography.



Resource availability and grazing effects

(Fujita et al. 2009)

Stream

Ridge

Near ridge

Upper slope

Lower slope

Foot slope Valley bottom

Soil moisture is low.

Grazing causes a negative effect by direct damage to plants.…Some plant species are eliminated because of the damage.

Soil moisture is high.

Grazing has a positive effect by improvement of light condition.…Plant species can coexist because of relaxing the competitive exclusion.


Summary 4. The relationships between biodiversity and livestock

In Mongolian pasturage, nomadic people indirectly

affect plant diversity in grasslands by herding

livestock.

The relationships between grazing pressure and

plant species diversity varies according to the

intensity of grazing pressure and resource availability

(soil moisture) of plants.


Summary of Today’s Topics

1.1. Even if only one species is eradicated, interspecific Even if only one species is eradicated, interspecific interaction can be drastically changed.interaction can be drastically changed.

3.3. Changes in landscapes bring local extinctions Changes in landscapes bring local extinctions because of decline in genetic variation, reduction of because of decline in genetic variation, reduction of habitats, loss of indispensable habitats, etc.habitats, loss of indispensable habitats, etc.

2. 2. Changes in biota affect availability of natural Changes in biota affect availability of natural resources or stability of ecosystems. resources or stability of ecosystems.


4. 4. Livestock grazing effects do not always decrease the Livestock grazing effects do not always decrease the plant species diversity.plant species diversity.


Column: Why is genetic variation important?

Chromosome from father

Chromosome from mother

Gene locus

a

b

Rh+

Rh-

AlleleGene locus and allele

The rhesus blood-group system

Rh+Phenotype



Gene locus




Appearance of RDG (x)

Locus 1

×

○

Locus 2

○

○

Locus 3

○

×

Locus 4

×

○

Locus 5

×

×

Recessive deleterious gene (RDG)

Column: Why is genetic variation important?


Behavior of recessive deleterious genein a case where genetic variation is high

× ○ ○ ○

○ × ○ ○

RDG does not appear.

Father

○ ○ × ○

○ ○ ○ ×

Mother

Column: Why genetic variation is important?


× ○ ○ ○

○ ○ × ○


× ○ ○ ○

○ ○ ○ ×


○ × ○ ○

○ ○ × ○


○ × ○ ○

○ ○ ○ ×



× ○ ○ ○

○ ○ × ○

Father

× ○ ○ ○

○ ○ × ○

Mother

× ○ ○ ○

× ○ ○ ○

RDG appears.

× ○ ○ ○

○ ○ × ○

○ ○ × ○

× ○ ○ ○

○ ○ × ○

○ ○ × ○

RDG appears.

Column: Why genetic variation is important?

Behavior of recessive deleterious gene in a case where genetic variation is low






Exercises

1. This illustration shows a food web consisting of 8 species. If the goshawk is eradicated, how would the population of the remaining species change?

White spruce

Goshawk Lynx

Willow ptarmigan

Red squirrel

Insects

GreyWillow

Snowshoe hare

Let’s do the exercises below:


Exercises

Let’s do the exercises below:

2. Degradation of biodiversity happens all over the world.Choose such an example near yourself and think what kind of effect brought the ecosystem.


Glossary (1/3) 　

Organisms’ tug-of-war over resources essential for surviving, such as food, light, nutrition, etc. ‘Intraspecific competition’ in the case of competition within the same species, and ‘interspecific competition’ in the case of competition among species.

CompetitionCompetition

One of two or more possible forms of a gene that are found at the same place on a

chromosome. See column in details.

AlleleAllele

Ecosystem function means functions essential for the sustainability of ecosystems, such as productivity of plants, formation of soils, circulation of substances, etc. Among ecosystem functions, those that are available for human activities or which provide human welfare are called ecosystem services. See chapter 1 for details.

Ecosystem function and serviceEcosystem function and service


Glossary (2/3)

A large area of land, especially in tropical countries, where only one kind of crop is cultivated.

PlantationPlantation

The place where a particular type of organism is normally found. Habitat must satisfy environmental conditions which are needed for the survival and reproduction of the organisms.

HabitatHabitat

Homozygosis means that there is the same allele in the gene locus. On the other

hand, heterozygosis means there are different allele in a gene locus. See Column

for details.

Homozygosis / HeterozygosisHomozygosis / Heterozygosis

A particular group of individuals of a species living in a particular area.

PopulationPopulation


Glossary (3/3)

Gene which brings harmful effect in the case of homozygosis. See column for

details.

Recessive deleterious geneRecessive deleterious gene


References (1/2)

Agetsuma, N. (2007) Minimum area required for local populations of Japanese macaques estimated from the relationship between habitat area and population extinction. International Journal of Primatology 28:97-106

Bezemer, T. M. and van der Putten, W.H. (2007)Diversity and stability in plant communities. Nature 446:E6-7

Chapman, C. A. and Onderdonk, D.A. (1998) Forests without primates: primate/plant codependency. American Journal of Primatology 45:127-141

Fujita, N. (2006)Sustainability of Mongolian nomadism from the viewpoint of pasture utilization. In Konagaya, Y. ed., “A Handbook of Mongolian Environments” pp.114-124, Kenbunsha (In Japanese)

Fujita, N., Amartuvshin, N., Yamada, Y., Matsui, K., Sakai, S. and Yamamura, N. (2009)Positive and negative effects of livestock grazing on plant diversity of Mongolian nomadic pasturelands along a slope with soil moisture gradient. Japanese Society of Grassland Science 55:126-134

Agetsuma, N. (2007) Minimum area required for local populations of Japanese macaques estimated from the relationship between habitat area and population extinction. International Journal of Primatology 28:97-106

Bezemer, T. M. and van der Putten, W.H. (2007)Diversity and stability in plant communities. Nature 446:E6-7

Chapman, C. A. and Onderdonk, D.A. (1998) Forests without primates: primate/plant codependency. American Journal of Primatology 45:127-141

Fujita, N. (2006)Sustainability of Mongolian nomadism from the viewpoint of pasture utilization. In Konagaya, Y. ed., “A Handbook of Mongolian Environments” pp.114-124, Kenbunsha (In Japanese)

Fujita, N., Amartuvshin, N., Yamada, Y., Matsui, K., Sakai, S. and Yamamura, N. (2009)Positive and negative effects of livestock grazing on plant diversity of Mongolian nomadic pasturelands along a slope with soil moisture gradient. Japanese Society of Grassland Science 55:126-134


Hedrick, P.W. (2001)Conservation genetics: Where are we now? Trends in Ecology and Evolution 16: 629-636

Jump, A.S. and Peñuelas, J. (2006) Genetic effects of chronic habitat fragmentation in a wind-pollinated tree. Proceedings of the National Academy of Sciences 103:8096-8100

Krebs, C.J., Boutin, S., Boonstra, R. (2001)Ecosystem dynamics of the boreal forest: the Kluane Project. Oxford University Press.

McConkey, K. R. and Drake, D. R. (2006)Flying foxes cease to function as seed dispersers long before they become rare. Ecology 87:271-276

Tilman, D., Reich, P. B., Knops, J., Wedin, D., Mielke, T. and Lehman, C. (2002)Diversity and Productivity in a Long-Term Grassland Experiment. Science 294:843-845

Hedrick, P.W. (2001)Conservation genetics: Where are we now? Trends in Ecology and Evolution 16: 629-636

Jump, A.S. and Peñuelas, J. (2006) Genetic effects of chronic habitat fragmentation in a wind-pollinated tree. Proceedings of the National Academy of Sciences 103:8096-8100

Krebs, C.J., Boutin, S., Boonstra, R. (2001)Ecosystem dynamics of the boreal forest: the Kluane Project. Oxford University Press.

McConkey, K. R. and Drake, D. R. (2006)Flying foxes cease to function as seed dispersers long before they become rare. Ecology 87:271-276

Tilman, D., Reich, P. B., Knops, J., Wedin, D., Mielke, T. and Lehman, C. (2002)Diversity and Productivity in a Long-Term Grassland Experiment. Science 294:843-845

References (2/2)


Authors & Credits

The Futurability of Biodiversity Chapter 5


Authors Naoki AgetsumaAtsushi UshimaruTakuo NagaikeZen-ichiro KawabataAya HatadaMartin Piddington

Applications CutPRO3 Real tough. Animal and Insect version (Design Office Kyowa)Microsoft PowerPoint®

Illustration & design Be4°TECH Koubou Yecoruka

Photos

Yuji IsagiShumpei KitamuraShoko SakaiWataru FujitaStewart Wachs

A. EmanonEchigo-Matsunoyama Museum of Natural Science, ‘Kyororo’Hiroki YamanakaMasashi IgariNaoki AgetsumaNational Institute for Environmental StudiesNoboru Fuijita 　Ryo Tsujino

Keizou HiraiMasatomi Matsuoka

Shumpei Kitamura

Data provider Takuo Nagaike

Documents

Copyright 2010 Research Institute for Humanity and Nature. All Rights Reserved. What will happen when biodiversity degrades? The Futurability of Biodiversity