Specific structure of primordial forests in the
Middle East and North Africa: Shaping landscapes to maximize functionality of
rain-cloud formation
Haruka Yoshimura, Ph.D.
Primeval forests for wetter climate control
Prior to humanization of landscape,
primeval forests thickly covered the land in the Middle East and North Africa.
The “Epic of Gilgamesh” vividly describes
the green mountains covered with deep primeval cedar forests, where the “tall cedars raised
aloft their luxuriance and cast a delightful shade,” in the lower
reaches of Tigris-Euphrates River Basin (in present-day Iraq, vicinity of Uruk;
31°19´N, 45°38´E), around 5, 000
years ago. During the reign of Pharaoh Snefru dated around 2,600 B.C., an
ancient Egyptian text known as the “Palermo Stone” mentions that forty ships filled with cedar wood arrived from Lebanon
to Egypt for construction of a ship of a hundred cubits (about 50 m or about
170 ft.) in length and to make the doors of a palace. At that time, cedar wood
resources on Mount Lebanon (34°18´N, 36°07´E), the chain of
mountains extending from Turkey into Palestine, must have looked inexhaustible.
Cedar wood had been a staple of the Phoenician economy for 3,000 years, from
the time of the Pharaoh Snefru of the Old Kingdom of Egypt (ca. 2600 B.C.)
until the reign of Emperor Hadrian (A.D. 117–138) of the Roman Empire (Mikesell 1969;
Markoe 2006).
Julius Caesar (100–44 B.C.) in Rome
was eager to exploit timber from the vast expanse of forests of Mount Atlas
that sloped toward Africa, where the deep primeval forests that remained must
have appeared unchanged since the world began (Perlin 2005). Today the
so-called North Western Sahara Basin, which extends over much of Algeria, Libya
and Tunisia, is a hyper arid region.
When the Portuguese first set foot on the
island of Madeira (32°39´N, 16°54´W) in 1420, about
520 km (323 miles) west of the African coast, it was so thickly wooded by
cedars and other species that they named it “isola de Madeira,” or “island of timber.” An early visitor of
a Portuguese navigator Diogo Gomes (1420–1500) mentioned that the island was so
well forested that he “could not see what
was on the ground because it was completely covered by trees” (Perlin 2005).
The principal groundwater aquifers in the
Middle East and North Africa were most recently recharged during Late
Pleistocene and Early Holocene when the climate of the area was much wetter
(Scanlon et al. 2006; Edmunds 2009). At that time, the active recharge to the
aquifers was maintained by sufficient surface water of massive lakes and river
systems along with the fairly deep surviving forests covering vast geographical
areas in the Middle East and North Africa. Sufficient surface water supply
originated with sufficient rainfall (precipitation).
The deep primeval forests covering these
vast geographical areas played a crucial part in occurrence of rainfall
(precipitation) via rain-cloud formation by the interaction between abundant
moisture released active transpiration of the forests and evaporated water from
the oceans, seas, lakes and rivers (http://harukanoor4.blogspot.jp/2016/).
Effectively, the deep primeval forests have evolved in a way to maximize the
function of rain-cloud formation over a period of 145 million years.
Acknowledging that freshwater is a
non-substitutable resource for food production and human life, an intrinsic
solution (shaping landscapes for returning precipitation by restoring
interaction between the atmosphere and terrestrial ecosystems) should be implemented
(http://harukanoor4.blogspot.jp/). New paradigms in land planning and
management, including urban planning and management, with strategic vision on
water governance are urgently required (Fig. 1). Understanding of the species
composition and forest structure of the primeval forests is essential to guide
the restoration of terrestrial biome to maximize its functionality of regional
hydrological cycle.
Evolution of temperate forests in the Northern
Hemisphere
During the Jurassic Period of the Mesozoic
Era, the “Age of Dinosaurs,” the Earth was
covered with non-flowering plants such as ferns, horsetails, and Gymnosperms
(seed-producing non-flowering plants). Jurassic Gymnosperms included
seed-bearing trees: Cycas, Ginkgo and conifers such as yew (Taxus),
the monkey puzzle tree (Araucaria), and cypress (Cupressus). The
rapid diversification of angiosperms (flowering plants) in the early Cretaceous
led to fundamental changes of terrestrial landscapes to angiosperm-dominated
ecosystems of the Cenozoic Era (e.g., Crane et al. 1995).
Continental Drift (the movement of the
continental plates) is closely tied to the global distribution of the tree and
plant genera. In the Jurassic, the supercontinent Pangaea broke up into the supercontinents Laurasia (North America and Eurasia) and Gondwana (Africa, South America, India, New Zealand, Madagascar, Australia and
Antarctica). In the late Cretaceous, when angiosperms had already achieved
widespread dominance, Laurasia split into North
America and Eurasia. Therefore, temperate forests in the Northern Hemisphere
show similarity between North America and Eurasia, composed of common flowering
tree genera such as oak (Quercus), beech (Fagus), hornbeam (Carpinus), birch (Betula), alder (Alnus), hackberries (Celtis) and maple (Acer). Tropical upland
forests are forests above 800 m in the tropical zone. These temperate tree
genera are also distributed in tropical upland forests in North America and
East Asia, occasionally crossing the equator in the Southern Hemisphere. Fir (Abies), A genus of
Eurasian conifer most closely related to the genus Cedrus (cedar), distributes in
the temperate zone and the tropical uplands in North America and East Asia,
mixed with the
flowering tree genera. As most temperate forests in North America and Eurasia
have been cleared by human activity for agriculture or human settlement, only
scattered remnants of original forests remain.
The Cenozoic Era is referred as the “Age of Mammals” because mammals rose to dominance with
the Cretaceous-Paleogene extinction event that wiped out remaining non-avian
dinosaurs. Rapid diversification of angiosperms and slow diversification of
gymnosperms continued and a mostly continuously distributed
angiosperm-dominated forest formed in the Northern Hemisphere during the
Tertiary Period of the Cenozoic Era. Human evolution began in the Quaternary
Period of the Cenozoic Era.
During the long formation period of the
widespread angiosperm-dominated forests in the Tertiary, Africa and Arabia
(both split from Gondwana) lay so close to
Eurasia that Eurasian temperate tree and plant genera dispersed over North
Africa and the Arabian Peninsula. In the late Cretaceous, Africa and Arabia was
moved northward to meet Europe and then collided with Eurasia in
Turkish-Arabian region from the Eocene to the Oligocene (35–30 million years
ago) in the Tertiary time (Jolivet 2000). Subsequently,
Eurasian temperate tree and plant genera spread southward into the temperate
zone and the tropical uplands in North Africa and the Arabian Peninsula, the
same as in North America and East Asia. Conversely, the southern elements
originated on Gondwana were dispersed northward into the warm
temperate zone of Eurasia.
(The Indian subcontinent collided with
the Eurasian plate about 50–55 million years
ago, after long drifting in the Indian Ocean. Species composition of the Indian
forests is different from the Eurasian primeval forests, as tree and plant
species (genera) evolved in isolation.)
The primordial forests in the Middle East and
North Africa
Although historical records show that
luxuriant forests once covered the Middle East and North Africa, today only
trees, shrubs and plants that have adapted to the arid conditions survive
in the arid areas in
the Middle East and North Africa. As the split between African plate and
Arabian plate started in the Eocene in the Tertiary time, African elements of
the flora are common to the flora of the Arabian deserts: tree genera such as Balanites
(Zygophyllaceae) and Maerua (Capparaceae); herbaceous genera such as Moltkiopsis
(Boraginaceae).
At the maximum development of the
temperate forest biome during the Tertiary, the terrestrial ecosystems,
composed of Eurasian temperate tree genera associated with African elements
originated on Gondwana, appear to have been widespread in the
temperate zone and the tropical uplands in the Middle East and North Africa.
Recent research of fossil pollen data
(Nascimento et al. 2009) shows that the temperate forest biome was once
widespread throughout Europe, North Africa and the Arabian
Peninsula. Fossil pollen data from La Laguna (Tenerife; 28°30´N, 16°19´W) in Canary
Islands, located 100 km (62 mi) from the African coast, indicates that two
Eurasian flowering tree taxa, oak (Quercus) and hornbeam (Carpinus) appear to have been
significant components from 4,700 to 2,000 years ago, which are now extinct on
the Canary Islands. Based on the recent research, the Eurasian flowering tree
taxa such as oak (Quercus), beech (Fagus), hornbeam (Carpinus), hackberries (Celtis) and maple (Acer) mixed with
Eurasian coniferous tree genera such as cedar (Cedrus) possibly spread
over the temperate zone and the tropical uplands in North Africa and the
Arabian Peninsula.
Species composition and forest structure of the primordial forests in
the Middle East. In the remnant cedar forests of Lebanon (on the Arabian Plate), Beals
(1965) indicates that the diverse Eurasian temperate tree genera such as oak (Quercus) and maple (Acer) are mixed with
cedar (Cedrus libani). Prior human
disturbance between around 12,000 and 10,000 years ago, pollen records from
Lebanon indicates that the primordial cedar forests were composed of Eurasian
temperate tree genera associated with African elements. Pollen data from the
Aammiq wetland [foothill of Mount Lebanon; 33°46´N, 35°46´E, 865 m above sea level (asl.)] and from
the Chamsine/Anjar wetlands (foothills of Anti-Lebanon Mountain; 33°44´N, 35°57´E, 856 m asl.)
indicate that the primordial cedar forests were composed of Eurasian flowering
tree genera such as oak (Quercus), maple (Acer), willow (Salix), chestnut (Castanea) and walnut (Juglans) mixed with
Eurasian coniferous trees genera cedar (Cedrus libani) and pine (Pinus), associated with
African elements such as Pistacia (Hajar et al. 2010).
The structures of
both the remnant cedar forests and the primordial cedar forests during late
Pleistocene show a typical Eurasian temperate forest, angiosperm-dominated
forest mixed with coniferous trees as a canopy component (Fig. 2).
Until around 5000 years ago, the
angiosperm-dominated forest mixed with cedar remained intact in the downstream
regions of the Tigris-Euphrates River Basin (on the Arabian Plate), as the Epic
of Gilgamesh suggests.
The Angiosperm-dominated forests mixed
with cedar were possibly widespread over the temperate zone and the tropical
uplands in the Arabian Peninsula.
Occurrence of fossil pollen of Eurasian
temperate tree genera, such as oak (Quercus), birch (Betula),
alder (Alnus), beech (Fagus), pine (Pinus) and cedar (Cedrus)
in the Arabian Peninsula, is generally interpreted as the effect of
long-distance transportation. However, based on the current research that the
temperate forest biome once widespread throughout the Arabian Peninsula, the
presence of the fossil pollen of Eurasian temperate tree genera could be
interpreted as the local presence.
Fossil pollen date form Pleistocene lake
sediment in An Nafud in Saudi Arabia (27°51´N, 41°26´E, in temperate zone on the Arabian
Plate) shows occurrence of Eurasian temperate tree genera, oak (Quercus), birch (Betula), alder (Alnus) and pine (Pinus) mixed with African
elements (originated on Gondwana) such as Vachellia
(considered members of genus Acacia until 2005), Maerua, Balanites
and Hyphaene (Schulz and Whiney 1986). During 34,000 and 24,000 years
ago, degraded remnant of the primeval temperate forests appears to have
remained in the Arabian Peninsula. Fossil pollen of Holocene lake sediments
from An Nafud and adjacent areas indicates that the landscape changed to
semi-desert of grasses with some shrubs during 8,400 and 5,400 years ago.
Occurrence of the fossil pollen, Vachellia (Acasia), Maerua (Capparaceae),
Balanites (Zygophyllaceae) and doum palm (Hyphaene), similar to
the present vegetation, indicates aridization of the oasis in the temperate
zone of the Arabian Peninsula. Though, pine (Pinus), the Eurasian
temperate coniferous tree genera tolerant to dry conditions, appears to have
still survived at the time.
Fossil pollen data from early Holocene of
Palaeolake Mundafan in southern Saudi Arabia, in the Rub,’ al-Khali, the ‘Empty Quarter,’ (18°32´N, 45°23´E, 860 m asl., in
tropical upland on the Arabian Plate), where inhabited by hippopotamus
(Crassard et al. 2013), shows occurrence of the Eurasian temperate tree genera
of pine (Pinus) mixed with
xerophytic (adapted to a dry environment) shrubs, Tamarix and Zizipus,
about 8,000 years ago (Lézine et al. 2010).
From around 8,000 years ago, disappearance of tree pollen types and increase of
herbaceous plants such as Poaceae indicate gradual aridization at the time in
the southern Arabian Peninsula (Lézine et al. 2010).
Fossil pollen data from early Holocene
palaeolake sediment of Al-Hawa in Yemen (15°52´N, 46°52´E, 710 m asl., in tropical upland on the
Arabian Plate) indicates occurrence of the Eurasian temperate
tree genera: oak (Quercus), birch (Betula), beech (Fagus) and cedar (Cedrus), mixed with
African elements: Vachellia (Acacia), Dipterygium
(Capparidaceae) and Tribulus (Zygophyllaceae) (Lézine et al. 1998). From 8,700 to 7,800
years ago, remnant of primordial cedar forests appears to have survived in the
tropical upland of the Arabian Peninsula.
The presence of the fossil pollen of
Eurasian temperate tree genera strongly suggests that the ancient deep forests,
composed of the Eurasian temperate tree genera associated with African elements,
were extended in tropical uplands on the Arabian Peninsula, at the maximum
development of the temperate forest biome during the Tertiary.
Species composition and forest structure of the primordial forests in
North Africa. In North Africa,
fragmented angiosperm-dominated forest mixed with coniferous trees such as cedar (Atlas cedar, Cedrus atlantica) survives in the
Atlas Mountains. In remnant forests of the Atlas Mountains, diverse Eurasian
temperate flowering tree genera such as oak (Quercus), birch (Betula), maple (Acer), willow (Salix) and
chestnut (Castanea) are mixed with
conifers such as Atlas cedar (Cedrus atlantica) and fir (Abies) as the dominant
canopy component.
Pollen and plant microfossil records show
that the Sahara in the present-day desert was either steppe, at low elevation,
or temperate xerophytic woods/scrub, or even warm mixed forest in the Saharan
mountains around 6,000 years ago (Jolly et al. 1998).
Fossil pollen data from La Laguna
(Tenerife, Canary Islands; 28°30´N, 16°19´W) shows occurrence
of two Eurasian temperate flowering tree genera, oak (Quercus) and hornbeam (Carpinus) associated with
African elements such as Phoenix and dragon tree (Dracaena), from
4,700 to 2,000 years ago (Nascimento et al. 2009). Based on the recent
research, distribution of the Eurasian temperate tree genera appears to have
been spread over the temperate zone in North Africa.
Fossil pollen data from tropical upland
in Africa indicates the presence of the Eurasian temperate flowering tree
genera during the late Pleistocene and Holocene period. Fossil pollen data from
Lake Victoria in Uganda (0°18´N, 33°20´E, 1,134 m asl., in
tropical upland) indicates occurrence of Eurasian temperate flowering tree
genera hackberries (Celtis) associated with Podocarpus
(a genus of conifers endemic to the ancient supercontinent Gondwana), from 13,000 years ago to present
(Kendall 1969). Similarly, fossil record from Ahakagyezi Swamp in southwest
Uganda (1°5´S, 29°54´E, 2,100 m asl., in
tropical upland) shows occurrence of Eurasian temperate tree genera hackberries (Celtis) associated with Podocarpus,
during the late Pleistocene to Holocene (Taylor 1993). Podocarpus pollen
dramatically increased around 4,000 years ago elsewhere in eastern Africa,
e.g., in the Lake Victoria in Uganda (Kendall 1969) and in the Ahakagyazi Swamp
in Uganda (Taylor 1993). In Eastern Africa, forests and woodlands had been
cleared for cultivation beyond 4,800 years ago. As Podocarpus favours
drier sites within moist montane forests, the Podocarpus expansion
suggests onset of drier climate due to decreased rainfall (Hamilton et al.
1986). Drought tolerant hackberries
(Celtis) increased simultaneously with the Podocarpus expansion.
A long history of
forest clearance and consequent soil erosion in Africa have significantly
transformed the regional hydrological cycle.
At the maximum development of the
temperate forest biome during the Tertiary, distribution of the Eurasian
temperate tree genera appears to have been widespread over the tropical uplands
in North Africa.
The island of Madeira (32°39´N, 16°54´W), about 520 km
(323 miles) west of the African coast, was thickly wooded by cedars and other
species when the Portuguese first set foot in 1420. An early chronicler commented
that “the trees growing
on Madeira attained such height they seemed to touch the sky.”
Prior human disturbance, the tall and
thick primeval forests such as in the island of Madeira in 1420, composed of
Eurasian temperate tree genera associated with African elements (originated on Gondwana) such as Phoenix, dragon tree (Dracaena)
and Vachellia (Acacia), were densely covered in the temperate
zone and the tropical uplands in North Africa.
Shaping landscapes to maximize its functionality
of rain-cloud formation
Evolution of high LAI vegetation
More than 3 billon years ago, early life
on Earth, photosynthetic bacteria, developed the capacity to efficiently
capture solar energy and use it to power the synthesis of organic molecules.
The energy of solar radiation has been harnessed through the process of
photosynthesis. About 475 million years ago, first land plants, which descended
from green algae (aquatic photosynthetic organisms), evolved. They were unable to grow
tall as lacking vascular structure (stems and roots). About 425 million years
ago, a new type of land plant, vascular plants, appeared in the Silurian Period
of the Paleozoic Era. The vascular plants are able to grow tall canopies to
capture more sunlight.
The terrestrial ecosystems seem to have
evolved to maximize the process of photosynthesis via forming tall canopies and
highly stratified foliage structure to capture more sunlight effectively. To
grow tall canopies and to develop stratified foliage structure for capturing
solar radiation effectively, terrestrial ecosystems appear to have evolved an
integrated biome composed of a mixture of conifers and flowering tree genera
with understory vegetation of diverse vascular plants (flowering plants,
conifers, ferns, horsetails and clubmosses) (Fig. 2).
Leaf area index (LAI, the ratio of leaf
area per unit ground area) is a powerful parameter of vegetation productivity,
as primary production (estimated amount of organic compounds fixed atmospheric
carbon dioxide via photosynthesis) is closely related to light interception. A
high LAI of over 8 is the level found in mature forests such as temperate
broad-leaved evergreen forests and tropical rain forests (Odum 1971; Whittaker
and Likens 1973; Chapin 2003).
Crucial role of high LAI vegetation in regional
hydrological cycle
Water is a renewable resource in the
sense that evaporated water returns via rainfall (precipitation) by the
interaction between transpiration of the terrestrial biomes and evaporated
water from the oceans, seas, lakes and rivers
(http://harukanoor4.blogspot.jp/). Photosynthesis is directly related to
transpiration under sufficient water supply conditions (e.g., Running and
Coughlan 1988), as the process of photosynthesis synchronizes with
transpiration. Primordial forests, an extreme system of the most highly evolved
high LAI vegetation, developed the capacity to provide the most abundant supply
of moisture via active transpiration, which in turn contribute to
cloud-formation.
Land governance incorporated the structure of
the primordial forests in the Middle East and North Africa
Today, being accustomed to cultivated
fields and large cities, it is difficult for us to imagine the density and
height of the high LAI terrestrial biomes composed of diverse trees and plants.
The “Epic of Gilgamesh” describes that
mountains in the lower reaches of Tigris-Euphrates River Basin were covered
deep forests “where the foliage
was so dense that the sun could barely shine through,” as
highly-stratified canopy foliage structure of the primordial cedar forests,
characterized by high LAI values, effectively intercept solar radiation. To
develop tall terrestrial biomes composed of biodiversity, it takes a long time
of about 425 million years from the first landing of plants. The primordial
forests in the Middle East and North Africa were looked like the Medieval
Period forests in the island of Madeira, which was so thickly wooded that “the trees growing
on the forests attained such height they seemed to touch the sky.”
The water resources upon which people
depend came substantially from the regional hydrological cycle that evaporated
water returns via rainfall (precipitation) by the interaction between
terrestrial biomes and evaporated water from the oceans, seas, lakes and
rivers. The land in the Middle East and North Africa has experienced decline in
this function. To avoid a catastrophic risk that stems from a spreading water
shortage and ever growing food insecurity, new paradigms in land planning and
management incorporating restoration of high LAI vegetation with the strategic
vision on restoring regional hydrological cycle are urgently needed.
For intelligent choice of Homo sapiens
Whittaker and Likens (1973) stress the
importance of high LAI vegetation of forests: “Stability of surface is again critical.
Given stable surfaces, land plants have so evolved that long-lived plants are
dominant. These plants use the biomass that is the accumulated profit of net
productivity for their extensive root and aboveground structures. These
structures are in turn part of the basis of high productivity through their
support of photosynthetic surfaces and contribution to the pattern of nutrient
use and retention.”
Ancient lore in the Middle East and North
Africa says that this area will someday “be green again.” However, natural
restoration of vegetation does not occur automatically, due to a long history
of forest clearance, consequent widespread aridization and lack of
biogeographical access to the tree and plant species once ubiquitous in the
terrestrial ecosystems.
Primordial forests composed of
biodiversity, extreme system of the most highly evolved of high LAI vegetation,
developed a most advanced system on Earth contribute to cloud-formation. Therefore,
restoration of high LAI vegetation mimic the natural system requires multiple
mixed planting with canopy forming tall trees, mid-story small trees/shrubs,
and diverse under-story vascular plants (e.g., Fig.1). Large numbers of tree
and plant species once ubiquitous in the terrestrial ecosystems are extinct in
the Middle East and North Africa. In order to shape landscapes with high LAI
vegetation structures, tree and plant genera from Europe, Asia (including
Japan) and Africa will substitute for the extinct genera in the Middle East and
North Africa.
Because of the critical feature that
there is largely no substitute for freshwater for human life and food security,
shaping water landscapes along with deep primordial forests is essential for
intelligent choice for sustainable future of humans. Today many lands all
around the world have declined contribution to the regional hydrological cycle
that evaporated water returns via rainfall (precipitation) by the interaction
between terrestrial biomes and evaporated water from the oceans, seas, lakes
and rivers, as most primordial forests have been cleared. As consequent water
shortage and growing food insecurity pose the challenge for our future, the
total land governance incorporated the high LAI vegetation structures is
urgently required around the world. The primordial forests have endemic
structures (e.g., the Pacific Northwest of North America, Waring and Franklin
1979). Appropriate for the biogeographical history, latitude, altitude, site
aspect and for our cultures, we should shape continuous lush landscapes over
vast geographical areas with maximize use of our ability to transform nature (see
explanation in http://harukanoor4.blogspot.jp/2016/).
References
Beals EW (1965) The
remnant cedar forests of Lebanon. J. Ecol. 53:679–694. doi: 10.2307/2257627
Chapin FS, III
(2003) Effects of plant traits on ecosystem and regional processes: A
conceptual framework for predicting the consequences of global change. Ann Bot
91:455–463. doi:
10.1093/aob/meg041
Crane PR, Friis EM,
Pedersen KR (1995) The origin and early diversification of angiosperms. Nature
374:27–33. doi:
10.1038/374027a0
Crassard R,
Petraglia MD, Drake NA, Breeze P, Gratuze B, Alsharekh A, Arbach M, Groucutt
HS, Khalidi L, Michelsen N, Robin CJ, Schiettecatte J (2013) Middle
Palaeolithic and Neolithic occupations around Mundafan Palaeolake, Saudi
Arabia: Implications for climate change and human dispersals. PLoS ONE
8:e69665. doi:10.1371/journal.pone.0069665
Edmunds WM (2009)
Palaeoclimate and groundwater evolution in Africa—implications for
adaptation and management. Hydrol. Sci. J. 54:781–792. doi:
10.1623/hysj.54.4.781
Hajar L, Haïdar-Boustani M,
Khater C, Cheddadi R (2010) Environmental changes in Lebanon during the
Holocene: Man vs. climate impacts. J. Arid Environ. 74: 746–755. doi:
10.1016/j.jaridenv.2008.11.002
Hamilton A, Taylor
D, Vogel JC (1986) Early forest clearance and environmental degradation in
south-west Uganda. Nature 320:164–167.
doi:10.1038/320164a0
Jolivet L (2000)
Mediterranean extension and the Africa-Eurasia collision. Tectonics 19:1095–1106. doi:
10.1029/2000TC900018
Jolly D, Prentice
IC, Bonnefille R, Ballouche A, Bengo M, Brenac P, Buchet G, Burney D, Cazet
J-P, Cheddadi R, Edorh T, Elenga H, Elmoutaki S, Guiot J, Laarif F, Lamb H,
Lezine, A-M, Maley J, Mbenza M, Peyron O, Reille M, Reynaud-Farrera I, Riollet
G, Ritchie JC, Roche E, Scott L, Ssemmanda I, Straka H, Umer M, Van Campo E,
Vilimumbalo S, Vincens A, Waller M (1998) Biome reconstruction from pollen and
plant macrofossil data for Africa and the Arabian peninsula at 0 and 6000
years. J. Biogeo. 25:1007–1027. doi:
10.1046/j.1365-2699.1998.00238.x
Kendall RL (1969)
An ecological history of the Lake Victoria basin. Ecol. Monogr. 39:121–176.
doi:
10.2307/1950740
Lézine AM, Saliège JF, Robert C,
Wertz F (1998) Holocene lakes from Ramlat as-Sab’atayn (Yemen) illustrate the impact of
monsoon activity in southern Arabia. Quat. Res. 50:290–299. doi: 10.1006/qres.1998.1996
Lézine AM, Robert C,
Cleuziou S, Inizan ML, Braemer F, Saliège JF, Sylvestre F, Tiercelin JJ, Crassard R, Méry S, Charpentier
V, Steimer-Herbet T (2010) Climate change and human occupation in the Southern
Arabian lowlands during the last deglaciation and the Holocene. Global Planet.
Change 72:412–428. doi:10.1016/j.gloplacha.2010.01.016
Markoe G (2006) The
Phoenicians. Folio Society, London.
Mikesell MW (1969)
The deforestation of Mount Lebanon. Geogr. Rev. 59:1–28. doi: 10.2307/213080
Nascimento L,
Willis K, Fernández-Palacios JM,
Criado C, Whittaker RJ (2009) The long-term ecology of the lost forests of La
Laguna, Tenerife (Canary Islands). J. Biogeogr. 36:499–514. doi:10.1111/j.1365-2699.2008.02012.x
Odum EP (1971) Fundamentals
of ecology, 3rd edn. W. B. Saunders Co., Philadelphia
Perlin J (2005) A
Forest Journey: The Story of Wood and Civilization. Countryman Press,
Woodstock.
Running SW,
Coughlan JC (1998) A general model of forest ecosystem processes for regional
applications I. Hydrological balance, canopy gas exchange and primary
production processes. Ecol. Modelling 42:125–154. doi:
10.1016/0304-3800(88)90112-3
Scanlon BR, Keese
KE, Flint AL, Flint LE, Gaye CB, Edmunds WM, Simmers I (2006) Global synthesis
of groundwater recharge in semiarid and arid regions. Hydrol. Processes 20: 3335–3370. doi: 10.1002/hyp.6335
Schulz E, Whitney
JW (1986) Upper Pleistocene and Holocene lakes in the An Nafud, Saudi Arabia.
Hydrobiologia 143:175–190. doi:
10.1007/BF00026660
Taylor DM (1993)
Environmental change in montane southwest Uganda: a pollen record for the Holocene
from Ahakagyezi Swamp. The Holocene 3:324–332.
Whittaker RH,
Likens GE (1973) Primary production: The biosphere and man. Human Ecology 1:357–369. doi:
1007/BF01536732
Waring RH, Franklin
JF (1979) Evergreen coniferous forests of the Pacific Northwest. Science
204:1380–1386. doi:
10.1126/science.204.4400.1380
No comments:
Post a Comment