Sentences with phrase «number of tree species»

I will say however, that many people who work in this area feel that the combination of the geographic extent and spread, number of tree species being attacked, and intensity of the attacks, makes the current situation worse than any in recorded history.

«Even with shade coffee the number of tree species can be reduced by 80 % or more.

In addition, the number of tree species with fruits was 169 percent higher, and fruiting individuals had 50 percent more of their canopies covered with fruits.

The advantage was persistent: five years after lianas had been removed, the number of canopy trees with fruits was 150 percent higher, the number of tree species with fruits was 109 higher and fruiting trees had 31 percent more of their canopy covered by fruits.

Not exact matches

Also, why the elimination of the guidelines for number of canopy strata, and minimum number of native tree species?

Not all tree species have the same number of annual growth rings that are active in the movement of water and mineral nutrients.

«Eucalyptus grandis and a large number of other tropical tree species are heat - tolerant, so long as they have an ample supply of water in the root zone,» Ornstein says.

Daniel Nepstad of the Woods Hole Research Center in Massachusetts says that the number of ant species falls drastically as the trees are cleared for ranching.

The researchers counted the number of species of trees on parcels of land in the Indonesian Borneo rain forest that had been selectively logged for tall trees, either 1 or 8 years ago.

When an alien species enters a new ecosystem, it can alter the environment in a number of ways: by eating native species (in its 50 years on Guam, the Australian brown tree snake has eliminated 9 of 13 native bird species); by spreading disease among them (introduced birds in Hawaii thrive in part because they are far less susceptible to the avian malaria parasite, also an introduced species, than native birds are); or by altering the environment in such a way that favors themselves (like melaleuca, an Australian tree that is spreading through the Everglades in part by changing the frequency and intensity of fires).

But, if this new family tree holds up, one species numbers fewer than 5000 individuals, making it one of the world's more endangered mammals.

In Brazil, for example, among several plots studied as the land recovered from pasture, there was a great deal of variation in the density of trees and number of species present even at just 10 years of regrowth.

Although the program included a large number of species across China as a whole, they found that the majority of individual forests were planted with only one tree species, such as bamboo, eucalyptus or Japanese cedar.

After counting up tree species from 1170 research sites studied by hundreds of scientists, a team extrapolated the number likely to exist across the entire region.

About 30 years ago, entomologist Terry Erwin of the Smithsonian Institution's National Museum of Natural History in Washington, D.C., came up with an equation to estimate the number of insects in the tropics by measuring how much beetles specialize on tree species.

The study, he says, demonstrates that the painstaking task of recreating evolutionary family trees for genera with large numbers of species is well worth the effort.

The number of species has declined as the trees have been cut down and the woodland reduced in size, and overgrazing has prevented natural regeneration.

Students can use the survey data to create bar graphs that show the numbers of trees of different species.

There are a large number of amphibian species in the world and some of the species most commonly kept as pets include the South American horned frogs, tiger salamanders, waxy monkey tree frog and the African clawed frog.

«There are also a number of hikes and tours, such as a walk in the Botanical Gardens, where you can find some 500 species of trees, or Jack's Walk in the Botanical Gardens, which offers some of the best views of the island once you reach its end.

El Yunque hosts a number of unique plant and animal species such as the endangered Puerto Rican parrot and the tiny coquis, an indigenous tree frog.

Kruger National Park is home to an impressive number of species: 336 trees, 49 fish, 34 amphibians, 114 reptiles, 507 birds and 147 mammals.

The order is a cosmopolite (plants found throughout most of the world including desert and frigid zones), and includes mostly herbaceous species, although a small number of trees (such as the giant Lobelia and the giant Senecio) and shrubs are also present.

It is also home to a number of rare and endangered species, including the southern cassowary and Bennett's tree - kangaroo.

Climate scientists have been making an inventory of the world's forests: they have counted more than 1 trillion trees and numbered the known species.

The compound is produced by a number of species of trees, including those most likely to be grown en masse for bioenergy.

It is of dubious value to even attempt to consider «tree growth» in terms solely of «temperature» and the quantity of refutation makes worthless the concept of doing such, regardless of tree / species numbers.

In Eastern North America, models for 80 tree species project range expansions for approximately 30 species and an equal number of range contractions.

Several migratory tree - living species of bats were being slaughtered «in unprecedented numbers» by wind turbines, said the researcher.

Persistent drought conditions have also adversely impacted water - dependent habitats and species within and downstream of forest uplands, as evidenced by heightened mortality of a riparian tree species in central Arizona [5] and declines in number of species and densities of native fish in the Gila River in southwestern New Mexico [6], [7].

There is NOTHING to relate ANY similarity for GRAVITY or «the Theory of Gravity» to either the «hockey stick» plot or «greenhouse supposition», certainly any such link is NOT found in SCIENCE... My only post to that thread, and that thread (being titled «hockey - stick - is - broken» last (it seems), is reprised here: ------ At April 25, 2006 2:38 AM, Peter K. Anderson a.k.a. Hartlod (tm) said... It is of dubious value to even attempt to consider «tree growth» in terms solely of «temperature» and the quantity of refutation makes worthless the concept of doing such, regardless of tree / species numbers.

It is widely accepted that aggressive beetle species overwhelm the trees» physiological abilities to produce defensive tissues and chemicals by recruiting threshold numbers of individuals (Christiansen [1985]; Wallin and Raffa [2000], [2004]; Huber et al. [2004]; Franceschi et al. [2005]-RRB-.

Will rapid transitions and species invasions lead to sudden changes in plant community balance, killing large numbers of trees or otherwise upsetting the local carbon cycle, and will those disruptions put more CO2 and methane into the air or remove it?

Some trees in the tropics can sink carbon at a rate of 40 trees per ton but it is impossible to place an exact number on tons per tree since there are too many variables (soil, sunlight, species, maturity, etc.).

As early as 1958, pioneer ecologists were marking out areas of forest — usually a hectare in size — and returning every few years to record the size, number and species of the trees found there.

But he says that this phenomena is happening in any number of various tree species.

Planting began with more than 70 varieties of trees, including a number of endangered native species such as mahogany, purple heart, and cocobolo rosewood.

Serviceberry: A number of species of Amalanchier, or serviceberry, are available, with varying heights ranging from shrub - sized to small tree, and with some producing a delicious blueberry - like fruit after the fragrant white flowers are pollinated.

These species kill by overwhelming, with coordinated aggression and sheer numbers, a tree's defenses, followed by a complete destruction of the tree's ability to transport the products of photosynthesis (e.g. sucrose, amino acids, hormones, etc.) through its transport tissue, the phloem or inner bark.

Because a tree can recover from some limited number of beetle attacks — by restoring its carbon balance and / or hydration over time — aggressive species like the MPB do not allow this to happen.

Also, a good piece on the first attempt to estimate the number of insect species dependent on (the energy of) one species of tree — http://faculty.plattsburgh.edu/thomas.wolosz/howmanysp.htm