Human impacts on natural ecosystems have been evident in Armenia since ancient times. The early development of agriculture and livestock breeding in Armenia resulted in significant changes to the use of the land. Over several thousand years human activity has led to the disappearance of forests, increased the area of land under irrigation, cultivation of desert and semi-desert habitats and the expansion of pastures and meadows. The current status and relative importance of different types of ecosystem reflects their economic significance, including factors such the level and type of use, their broader ecological functions, the value of the species and genetic diversity they support, and their resilience to both natural changes and human impacts.

In the context of these factors mountain steppe, semi-desert and forest ecosystems are considered to be of key economic importance, given patterns of human settlement, suitable climatic conditions and opportunities for agriculture. Most arable land and human settlements in Armenia occur at altitudes below 2,200m. Of a total of 1,229,700ha of arable land, 20% occurs at altitudes below 1,000m, 33% between 1,000m and 1,500m, and 47% above 1,500m - in regions dominated by mountain steppe ecosystems. Semi-deserts and mountain steppes are also important in supporting various forms of cultivation, while meadows in semi-deserts are used as a source of horticultural material. Forest ecosystems are of particular importance, given their roles in soil protection, climate regulation and in supporting a range of biodiversity. Forest ecosystems support a wide range of plant species of economic importance. These include over 200 species of edible plants, 2,000 species of plants used as animal fodder, 120 species of wild berries, 350 species of plants visited by bees, 120 aromatic plant species, and 130 species important as a source of vitamins.

In addition, to the general importance of these ecosystems, a number of specific sites have been identified which support ecosystems of global or regional significance, and are rich in endemic, relict or rare species. These include:
· A unique assemblage of species of wild relatives of crops occurring near Yerevan
· Stands of plane trees (Platanus orientalis) near the Tzav river valley.
· Psamophpil desert on the bank of the Vedi river.
· The habitats supporting the endemic species of insect 'vordan karmir' (Porphyrophora hamelii) in the Ararat valley.
· The open woodland and semi-desert ecosystems of Central Armenia, with its unique and rich associated fauna and flora.
· Relict wetland meadows in the Lori area.
· Stands of yew (Taxus baccata) and hazel (Corylus colurna) in the Agstev river basin and Zangezour.
· Rhododendron habitats in sub-alpine regions of the Pambak and Tsaghkunyats ranges.
· Habitats of the sub-Arax mountain ridges where populations of Armenian mouflon (Ovis orientalis gmelinii) occur.

Forests are one of the most seriously threatened ecosystems in Armenia. Archaeological data indicates that around 40% of the land was originally forested. Since then forest cover has declined significantly as a result of both changes in climate and human impacts. The expansion of the human population has led to increased pressure on land for grazing and agriculture, resulting in forest clearance. In addition, two intensive periods of deforestation have occurred. Between the 1930s and 1950s, around 450,000m3 of wood was extracted annually from Armenian forests for industrial use. Extensive deforestation also took place between 1992-1995, during the period of economic blockade and energy crisis. A combination of poor forest management and illegal felling resulted in damage to around 27,000 ha of forest (more than 8% of the total forest area), including the total clearance of around 7000 ha. During this period, the forests around Yerevan, Gegharkunik, Lori, Kotayk, and Armavir were the most severely damaged.

Today, forests cover less than 10% of the land surface of Armenia. Forests are now concentrated in the north-east of the country, and in some areas, such as the Ararat valley, Vayk and Sevan regions, only small scattered patches of forest remain. These isolated patches are prevented from regenerating due to the pressure of uncontrolled felling and their use as pasture land. Further forest declines in some areas (such as Vaik and Sevan) have resulted from increases in forest pests and changes in the hydrological regime of forests.

The threats to wetlands in Armenia are clearly illustrated by the changes in Lake Sevan. This large, alpine lake is extremely important to Armenia, in terms of its water resources, ecological role, and unique fauna and flora. Lake Sevan effectively represents an important reservoir of water for Armenia and the wider Southern Caucasus region.

Since the 1930s the development of the industrial, agricultural and energy sectors have relied on the water resources of Lake Sevan. Off-take of its waters supplied irrigation systems for agriculture and hydroelectric power stations downstream. Water from the lake irrigated around 100,000 ha and generated more than 2.5 million kW of electricity, thus providing an important contribution to the socio-economic development of the country. However, such extensive off-take of water also resulted in a serious ecological disaster, with significant falls in the level of the lake. Since 1933 the level of the lake fell by 19m, and its overall volume decreased by 42%. As a result the average temperature of the lake increased, oxygenation levels fell, resulting in eutrophication and algal blooms. The first signs of the lake's eutrophication were recorded in 1964, when green and blue algae blossomed in the lake.

The decline in water levels also affected the whole of the Sevan watershed. Around 10,000ha of surrounding wetland and semi-wetland areas dried out, as did the neighbouring Lake Gilly.

The drainage of the lake also had significant effects on the biodiversity of the lake and surrounding areas. Populations of around 60 species of plant are considered to have declined as a result of the draining of Lake Sevan. Within the lake, the principal breeding sites for Sevan trout were lost, and populations of this and other endemic fish species, have declined. The Sevan wetlands were previously used by up to 160 species of migratory birds, only 50 of which are now recorded. Today the numbers of birds using the whole Sevan watershed are lower than those recorded on Lake Gilly alone in 1939, and waterbird populations continue to decline. The populations and diversity of mammal and reptile species in the area have also declined significantly, and a number of spaces are considered to be threatened.

Cultivated lands represent 80-90% of the area of the semi-desert zone, and natural ecosystems have been extensively damaged as a result of uncontrolled irrigation and agricultural intensification, which has resulted in increased soil erosion, salinity and pollution.

Uncontrolled grazing by livestock threatens many of the natural pastures of the mountain steppes and alpine and sub-alpine meadows. Serious degradation of pastures and meadows has occurred over the last 100 years, with the most significant impacts recorded in the grasslands of Vaik, Zangezur, Mount Aragats and Pambal.