About 4,000 years ago the first Eskimo tribes reached Northern Greenland after a migration taking some thousands of years from Asia via the Bering Strait, then along the North American coastal areas and over the Canadian Arctic archipelago. They settled primarily in the northernmost part of Greenland, where archaeological finds are the basis of our knowledge of their life. Subsequent waves of immigration resulted in settlements to the south, along Greenland's east and west coasts (Fig. 1).

Apparent effects of 2,4-D (2,4 dichlorophenoxyacetic acid, amine form) on some flora and fauna were observed following aerial application, under adverse meteorological conditions, of the chemical for control of Perennial Ragweed (Ambrosia psilostachya) in pasture, on the Author's farm in Oklahoma. Ragweed was greatly reduced, but there was widespread damage to a whole range of garden crops and trees, a few of which were killed. Damage to some tree species began to be reversed a few weeks after the spraying, but with others, sitespecific infestations of Spring Cankerworm and Fungi greatly extended the period of damaging conditions.

The overall objective of development should be to improve the quality of people's lives, yet economic development without due environmental protection commonly leads to ecological or environmental impacts which have the reverse effect of reducing the quality of human life. A table showing some of the major environmental impacts that can result from uncontrolled rural development is presented to illustrate the fact that developmental activities with no environmental protection can be very seriously detrimental to the rural environment. Therefore, an environmental impact assessment, both short-term and long-term in scope, should be made of any major development scheme as a basis for drawing up strategies for minimizing undesirable impacts. Although a number of techniques are available for such impact assessment, the checklist and matrix approaches appear to be the most suitable for use in Southeast Asia, where impact studies are only just beginning to be introduced.

A consistently declining rate in the production of local foodstuffs has been noted in recent years in many third-world countries. One of the measures taken by the governments concerned in attempting to stop this alarming trend, has been the accelerated development of modern agricultural practices based on irrigation and the use of fertilizers.

Unfortunately, the environmental aspects have, too often, been overlooked in the development of modern irrigation programmes during the second half of the present century. This has, seemingly inevitably, resulted in a severe spread of water-borne diseases among people living in the areas that were so developed.

Spartina alterniflora is the dominant endemic saltmarsh angiosperm along the East and Gulf coasts of the United States. Dieback of S. alterniflora became evident through aerial surveys of the Lower Cape Fear Estuary of North Carolina. The areas affected varied in size, the largest being greater than 40 ha in areal extent. As S. alterniflora productivity losses can subsequently affect the productivity of the estuarine detritus-based food-web, studies were initiated in 1975 to examine the dieback phenomenon, follow successional trends, and determine the recolonization potential of S. alterniflora in dieback-affected salt-marshes.

Three S. alterniflora dieback sites in the Lower Cape Fear Estuary were selected for study. Two of the sites, both above mean high-water, were recolonized by Salicornia europaea, Distichlis spicata, Scirpus robustus, Spartina patens, and S. alterniflora. At a third site, found to be below mean high-water, all volunteer plants were of S. alterniflora. Final stabilization of all three sites was mainly by S. alterniflora, with the living standing-crop biomass ranging from 341 to 1,565 g/m2 in September of 1978.

Experimental plots within each of the three dieback sites were sprigged with S. alterniflora plants from three sources: (i) sandy dredge-material, (ii) volunteer plants within affected sites, and (iii) unaffected sites near the dieback areas. The success of these sprigs was strongly site-dependent. It is suggested that the plants used for revegetation of dieback sites should be obtained from areas similar to the site that is being transplanted and/or plants which have large rhizome systems.

Environmental problems of agriculture constitute some of the most complex and significant problems of modern times. They are found in all countries, but are most prominent—and tend to be most serious—in Third World countries located in ecologically vulnerable areas. Their roots commonly lie in the culture of the population, the farmers' behaviour, or the economy of the area.

In order to assess patterns of agricultural development in general, or to assess the implications of development projects, we must include the environmental, behavioural, and policy, dimensions of the agricultural production system into a single framework, so that we can understand both the problems as narrowly defined and the measures which must be taken in order to solve them.

One way of doing this is through a comprehensive, out qualitative, overview of the system. This provides a general framework for any analysis, and it can be so simplified that a particular problem can be treated in a meaningful and adequate fashion.

Photochemical smog in the densely-populated coastal region of Israel often results in temporary atmospheric ozone concentrations in excess of 0.1 ppm. In view of the rapid growth in urban—industrial development, energy consumption, and motorized traffic, these concentrations are increasing from year to year and the same is presumably true for other Mediterranean countries suffering similar conditions.

Moreover, as in California, these photochemical air pollutants can be transported inland under suitable meteorological conditions and may lead to ozone concentrations well above 0.05 ppm even in remote mountain regions with forested slopes. This is the case in the Shaar Hagai canyon leading to Jerusalem, where more than 0.2 ppm oxidant concentrations have been measured and where widespread decline and mortality of Pinus hale-pensis is occuring, accompanied by severe infestation by Matsucoccus josephi scales and Scolytidae beetles. Earlier stages of this decline can also be observed in other planted pine forests in Israel.