Glossary

Humankind

Humankind’s impact upon the landscape is so pervasive that often, in urban and agricultural landscapes, we forget about the other components altogether. Conversely, when we are in the forest (which may seem to city eyes wild and natural), we often fail to see that the landscape is often as influenced by man as any city or plantation.

For instance trade in the forest products of the Philippine islands was well established a thousand years ago and, by the time the Spanish colonization started, there were a number of well established trading centers linked with Arabia, China, Europe and India, which exported luxury forest products such as hard-woods, rattans, camphor and a variety of resins. The collection of these products will have had a significant impact upon the natural Ecosystems of the islands’ forests. Hunters, and collectors of non-timber forest products influence ecosystemsmisEcosystemsPop because of their direct impact upon the communities of hunted animals; because they make tracks through the forest, provoking seed distribution of useful plants; and because even temporary settlements tend to introduce or favor plants which are useful.

Humankind, Modern

Where Ecosystems are either degrading towards non-viability or are already non-viable as a result of humankind’s presence. Most human societies are in this category. In fact so pervasive is humankind on the earth that there are signs that the Biosphere is becoming a non-viable.environment not only for humankind himself but for most other species.

Humankind, Natural

Where humankind’s habitat demands are in a stable balance with the Ecosystem in which they live. Pre-agricultural hunter/gatherer societies are examples. It is unlikely that any truly natural populations of humankind are left on earth.

Humus

The nutrient-rich end product of the decomposition of Soil Organic.

Hydrology And Water Quality

Natural hydrological characteristics are a function of geology, topography and climate. Thus, in any given place at any given time, water may arise either locally, as stored ground-water or rain, or from outside as upstream water or downstream tidal pressure.

However the activities of humankind can have a profound influence on the hydrology of an area. For instance a natural forest Ecosystem tends to act as a sponge, soaking up water in wet weather and releasing it slowly in dry, thus moderating the water supply to a river system. Where natural forest is removed or substantially transformed, this sponge function of the forest – effectively a natural reservoir – is lost so that flooding becomes more frequent in wet weather and river failure in dry. The same process may apply to lakes and to ground-water systems.

See the Water Cycle.

Inorganic

Non-living material. See Organic.

Insects

Insects are a class of Arthropods; they have one pair of antennae, three pairs of legs and three body sections, and often also have wings.

Larvae

Insects go through a larval stage in their life cycle, between the egg and the adult form. After hatching from the egg, a larva goes through a period of prolific eating before entering the pupa or chrysalis stage, after which it metamorphoses into an adult. As a food source for other animals, larvae are often the most nutritious form of an insect.

Pl. larva

Mangrove Forest

The mangrove forest is a community of salt-tolerant trees, with associated shrubs or vines and other organisms, that grows in a zone roughly coinciding with the intertidal zone along protected tropical and subtropical coasts and occurs in tidal zones with brackish water (WB, 1989).

The development of mangrove forests depends upon: tropical or subtropical tidal waters; water-logged alluvial deposits; a brackish water regime, lying between the high and low tide levels; and protection from the battering of oceanic waves.

Three key points should be made regarding their ecology.

MANGROVES TOLERATE, RATHER THAN PREFER, BRACKISH WATER. There are only a few mangrove species, and they are not all closely related; what they have in common is the ability to tolerate brackish water. It must be stressed that mangroves do no require brackish conditions; they actually prefer lower salt concentrations, but compete badly with other species. However their ability to thrive in brackish, waterlogged conditions is unique among the tropical plants, and gives them the competitive edge to overrun these coastal areas.

MANGROVES ARE PIONEERS. Mangrove forests represent pioneer communities, colonizing new alluvial deposits and helping to form new land. Once in place, mangrove roots trap and helping to form new matter; this material, in addition to the biomass of the mangrove trees themselves, eventually creates a rich organic soil rising above the high tide mark. From them on, freshwater plant species can begin to invade the ecosystem and the weaker mangrove species are displaced.

MANGROVES WILL NOT DEVELOP ON BARE SAND. They need at least a layer of silty or sandy clay.

Merrill-Dickerson Line

See Biogeographical Sub-regions.

Mollusks

Mollusks is a large group of unsegmented aquatic animals, soft-bodied but often hard-shelled. The group includes octopus and squid, but also mussels, oysters, periwinkles and snails.

Mutual Coexistence And Competition

The habitats of the ants, the aphids and the Aphid Eaters do not overlap: each has its own Niche. However, each individual competes with members of its species for resources, for mates and for living room.

Natural Ecosystems

These are ecosystems largely determined by the natural environment (e.g. the mossy forest of Mt. Pulag), as opposed to one that is largely determined by humankind (e.g. a Gmelina plantation or a rice paddy).

Nematodes

Nematodes are roundworms, often as parasites in the guts of animals.

Niche

The home of an organism, or how it fits into and makes a living in its natural ecosystem.

Omnivore

Animal that eats meat and plants.

E.g. Man, rats, crows, turtles, carp.

Organic

Material which is living or which has arisen from living things.

Ozone Layer

The Ozone Layer is the Stratosphere, a part of the Atmosphere that starts at about 10 km altitude, having a much higher concentration of ozone and a much lower concentration of water than the troposphere below and in much we live.

The value of the Ozone Layer is that id limits the dangerous Ultra Violet (UV) rays of the sun from the reaching the Troposphere in which most life exists. UV rays are particularly damaging to the germination of seeds (such as rice and wheat), to marine life and especially Zooplankton and to naked skin (causing skin cancer in humans and apparently killing Amphibians – see Classes of Life – such as frogs).

Ozone molecules are made up of three oxygen atoms (normal oxygen being made up of two) and hence, the 0-zone. It is created by lightening and the sun’s rays. It is naturally broken down by the UV rays, themselves, but in natural conditions, creation of Ozone balances destruction over the year, wearing thin, for a variety of reasons, during the spring over the poles.

Modern p pollutants and especially Chlorofluorocarbons (CFCs) are destroying the Ozone Layer.

See the Greenhouse Effect.

Photosynthesis

Photosynthesis is vital to both plant and animal life because it enables plants to capture the Energy of the sun. Animals obtain their energy by eating plants. It is a chemical reaction, enabled by the sun’s energy that takes place in the green chlorophyll of plants. In this reaction, Carbon Dioxide (CO2) from the air is combined with Water from the soil to make Sugar (a Carbohydrate), releasing Oxygen as a by-product. The Oxygen is essential for Respiration in both plants and animals.

The sugar (actually glucose) so formed, is a source of energy for the plant, or a precursor to more complex types of Carbohydrates such as the starch in a sweet potato. These carbohydrates may be used by the plant itself for further growth, and/or then eaten by humans and other animals, because they can be broken back down into simpler carbohydrates again to release the stored energy.

Polychaete Worms

Worms named for their bristles or ‘Chaetae’, which enable them to move rapidly through the water and to burrow. The most common is the writhing Neris, with an undulating fringe of chaete up to 15 centimeters in length.

Predator

An animal that survives by feeding (preying) on other animals (its prey).

Productivity

A tree is a PRIMARY PRODUCER, converting solar energy and inorganic material into living matter. SECONDARY PRODUCERS depend upon a primary producer and each other to live: for instance an Aphid may suck the sap from the leave stems of the tree. The Productivity of an Ecosystem depends on its inorganic resources such as water and soil nutrients, while production itself is activated by Energy.

See Bioactivity.

Protista

One of the Kingdoms of Life being singled celled organisms. See Classification of Life.

Quaternary

We live in the QUATERNARY geological period which started about 1.8 million years ago. It includes the period within which modern man evolved to his present form, Homo sapiens becoming dominant between 500,000 and one million years ago. The Quaternary also covers the time in which the primary topographical features of our world developed, largely as a result of a series of ice-ages.

(The TERTIARY period extended from 65 million years ago to the start of the Quaternary, and covers the period during which the old super-continent of Gondwanaland drifted apart to give the continents, oceans and major geological features more or less as we know them today).

Resource Cycles

All the natural resources of the Biosphere are re-cycled over time: nothing is lost. The cycle may take millions of years as with the carbon in mineral oil (see Carbon Cycle) , a few months or years as with water in the Water Cycle or perhaps only a few hours as in Photosynthesis.

A tree takes its nutrition from the soil. Nutrients are returned to the soil when leaves fall from the three and when it dies.

Only does Energy come from outside the biosphere and is lost as heat when it is used.