Efforts to protect the wild Vicuña, an endangered relative of the domesticated Llama and Alpaca of the central Andes, and to increase the species' numbers, have been more successful in achieving technical wildlife management goals than in complementing agro-pastoral activities of the indigenous peoples of the region. In both Pampa Galeras National Reserve in Peru and in Lauca National Park in Chile, lack of consultation with native pastoralists, whose lands the reserves occupy, reflects weak commitment to broader social and economic goals on the part of national authorities, as well as the inadequacy of international technical assistance in involving local communities in such projects.

Specifically, those projects have neglected to consider the importance of local patterns of land tenure, which are only in small part communal, and of economic differentiation with those communities. At the same time, authorities have controlled or monitored access to such subsistence resources as pasture and fuel for local residents, while failing to offer short-term alternatives for economic opportunity. This is in contrast to the free hand enjoyed by energy and agricultural irrigation projects such as those which benefit Chile's Atacama port of Arica. Continuation of such policies jeopardizes long-term success of wildlife protection as well as the economic future of the region's human inhabitants.

The formation of quasi-tubular voids in the subsoil, known as ‘piping’, is an important form of subsoil erosion that arises when substantial volumes of subsurface lateral throughflow pass through dispersible subsoils. Amongst the environmental factors that favour the development of piping are high contents of expansible clay minerals, a severe dry season, and convexities in the slope profile. The first two of these are characteristic of considerable areas in Central Tunisia.

In addition to natural slope-convexities, further topographic loci for pipe initiation and development are provided by the artificial convexities introduced into the slope profile by the construction of conservation banks. The earthworks are designed as protection against surface erosion processes, which prevail for most of the year in this part of Tunisia. However, it appears that the banking is particularly vulnerable to piping, which is causing considerable disruption. Australian experience indicates that banking should be used very sparingly on soils which are at all prone to piping, and that care is needed in both the alignment and construction of such banks as are deemed unavoidable.

In the context of ‘ecology’ and ‘development’, both these terms are usually ill-defined. Development, a finite process, is nevertheless conceived as sustainable, while ecology is only used in a qualitative way in this context. Development concerns resources—renewable and nonrenewable—both of which are finite in their exploitability. Ecology in land-use concerns the interference of Man as a biological species in ecological processes.

Integration of ‘ecology’ in ‘development’ requires the following steps:

1. Quantify the resources, both renewable and non-renewable, to be developed in terms of carrying capacity and inputs available.

2. Determine the regulating ecological factors in both the natural ecosystem and the land-use system.

3. Assess the interventions needed to counter limiting factors, their effectiveness, and their (side-)effects.

4. Define measures to be taken in such a way that they can be integrated with cultural, social, and economic, data, in order to arrive at a balanced approach to development.

Four conservation areas in the maritime Antarctic (three Specially Protected Areas and a Site of Special Scientific Interest) are compared with neighbouring islands which have not been awarded similar conservation status. Comparisons are carried out by using the terrestrial arthropod fauna, as opposed to the plant communities. Results indicate that arthropod diversity can vary significantly between localities for samples collected from the same vegetation types, but that within a limited geographical area the diversity of such faunas is similar.

Prespa National Park in Greece is an important breeding-area for rare and endangered waterbird species, but people living within the Park and using its resources create serious conservation problems. An environmental management plan which will regulate mainly the human activities within the Park is therefore necessary. Such a plan should be based on a land cover/use analysis of the area, for which much of the necessary information, in the form of a thematic map, has been collected by interpreting blackand-white aerial photographs. The procedure involved the development of a classification system, transferring the interpreted data onto a base-map, field-checking the results, and tabulating the area measurements with the pertinent errors.

Of the total Park area (25,690 ha), 66.5% is classified as terrestrial (forestland, rangeland, agricultural land whether irrigated, non-irrigated, or abandoned, wet meadows/marshland, barren and eroded land, and urban areas), and the remainder as aquatic (water, reedbeds). The most extensive category in the Park is forestland, much of which is seriously degraded. Rangeland provides forage for sheep and goats, being also degraded owing to uncontrolled grazing. Wet meadows/marshland are invaluable as waterbird breeding and feeding habitats, but the present use of this category as grazing fields, and its proximity to agricultural land and to the existing irrigation/drainage system, have all had negative impacts on the resource. Irrigated land is almost half of the cultivated area.

The abandoned agricultural land is interspersed within the forestland and is a result of the human population decline in the area, while barren and eroded land has resulted from prolonged land misuse. Twelve old villages are distributed over the Park, being visually unobtrusive. Lake Mikri Prespa is the main water-body and covers almost the entire nucleus of the Park. Extensive reedbeds are found along the lakeshores, which are the main breeding habitats of certain waterbirds. As land cover/use analysis of the Park has shown much serious environmental degradation, conservation measures should be undertaken urgently.

Experimental trampling was carried out in recently-burned and unburned areas of a dry sclerophyll forest. Percentage cover was greatly reduced by burning and trampling. Plant numbers were relatively unaffected by burning, and trampling had approximately the same effect on plant numbers in recently-burned and unburned areas.

The reduction of cover and plant numbers to 50% of their original value by fewer than 16 passages was near to that predicted on the basis of the low primary productivity of the ground-flora, and suggests that this type of vegetation is quite vulnerable to trampling.

The effects of human activities on shorebirds migrating through Raritan and Delaware Bays (New Jersey, USA) were examined from late April to late October 1982. Less than 5% of the 471,055 shorebirds counted in the censuses were in Raritan Bay, and only eight species accounted for 95% of the total. Bird populations peaked during late May to early June, and had a secondary peak in early August. People walking accounted for 43% (Raritan Bay) and 50% (Delaware Bay) of the disturbances. Other disturbances, in descending order of abundance, were of fishermen, airplanes, dogs, clam-diggers, off-road vehicles, boats, children, and joggers.

Studies have illustrated a sensitivity of the climate of the Arctic to natural and human-induced perturbations which greater than that in mid-latitudes or the tropics. This may be due, in part, to positive feedback linkages between the atmosphere and the cryosphere. We are only beginning understand the nature of the process linkages within the atmosphere-cryosphere-ocean-Biosphere system, however, and this is reflected in the discrepancies between various model simulations. This uncertainty increases our vulnerability to climatic change and variability. In the development of policy regarding management and development of our Arctic Heritage, we must attempt to reduce our vulnerability: we must be able to simulate the physical consequences of a perturbation with some veracity, and translate the results into the language of the policy analysts.

Three areas of research are highlighted as being important contributions towards this objective. The first is the derivation of climatically significant parameters from remotely-sensed data. Our climatologies and model validations are based upon spatially-biased data which include undetermined errors. With remotely-sensed imagery, we have access to previously inaccessible regions as well as spatial consistency in the data. The second area of research the detailed study of micro- and mesoscale processes at climatic ‘oases’. We must understand processes at these scales, and their linkage to the macroscale, if we are to design realistic General Circulation Models to simulate new climate states. The third area is effective communication of our knowledge in a form amenable to policy analysis. Current research is directed towards evaluating the impact of climatic variation in terms of risk assessment, and consideration of the policy implications of possible future climatic regimes through scenario analysis.

A quantitative measurement of tourist off-road driving was conducted in Masai Mara National Reserve, Kenya. Off-road driving was simulated in a grassland area of the Reserve that was heavily used by tourists. A mathematical model was employed to estimate the overall impact of tourist off-road driving on the Reserve's grassland communities.

The results of off-road driving simulation experiments showed that damage increased with the number of vehicular passes. Off-road driving was more destructive to the vegetation at the loops than on the straight. The magnitude of the estimated loss due to extrapolation of the findings of the simulation experiments to the whole reserve was very small. The aesthetic quality of the reserve was, however, adversely affected by the off-road driving, as was, doubtless, the privacy of the animals.

The love for ancient desert sport, dwindling of the population of Houbara Bustard (Chlamydotis undulata) in the traditional hunting grounds of the Gulf States, Middle East, and North Africa, and also in some accessible parts of Pakistan through hectic mechanized hunting, has attracted the now-rich Arab falconers to strike at the populations wintering in relatively inaccessible areas of Baluchistan during the last 5–10 years. The present paper is the first known attempt at analysing the multidirectional effects of falconry in that last area, and depends upon the information collected during the Author's tours of different areas of Baluchistan and through information collected from various agencies.

The falconry that is now being done in the wintering grounds of the Houbara Bustard in Baluchistan is liable to have a very severe impact on the birds' population as the summering population is packed in some 1/8th of its summering grounds, thus yielding a very high density of birds. The falconry activities not only constitute a direct assault on the population of the Asian Race of Houbara, with a hunting toll of 4,955 during 1984–85 (a progressive increase from 418 during 1981–82 as reported but in reality expected to be much higher). There is also a significant effect on the population of falcons, some 300–400 being used every year, though the actual toll is probably much higher, as many are lost during trapping, training, transportation, and selling. The hunting parties are also responsible for direct and/or indirect killing of associated wildlife including hares, various deer, See-see Partridges, sandgrouses, Stone Curlew, and Cream-coloured Courser, while some 200 head of antelope were taken out of their ecosystems and sold to, or wasted in the hands of, falconry parties during the 1983–84 season.

The hectic activity of the falconers in the area, and their associated men and materials, are responsible for disturbing the biological phenomena of the animal wildlife, including hormonal balance and feeding activities. The period of mating and reproduction of most of the desert animals coincides with the falconry in the area, and hence these activities result in the production of malnourished, biologically unbalanced individuals.

The indiscriminate killing of Houbara and falcons may result in unbalanced ecosystem, with the massive elimination of Houbara resulting in increases in the populations of harmful organisms lying at lower trophic levels, and decreases in the populations of organisms lying at higher trophic levels. The elimination of raptorial falcons has probably resulted in increases in the populations of rodents in the northeastern part of Baluchistan and hence increased damage to agricultural crops or water channels. The falconry also has the potential of physically destroying the habitat through crushing of the slow-growing plants, denuding the camping sites through movement of men and materials, dumping of nondegradable wastes, and woodcutting for camp fires. The movement of heavy hunting vehicles sometimes causes severe damage to small earthfilled dams that are used for storing irrigation water, slowing rapid runoff, and recharging ground-water resources.

Over the years, the problems facing conservation have changed. The 20th century has been characterized by two pertinent traits—concern for wildlife and the explosive growth of human population—both destined to loom larger and larger as the century progressed. As an example, the soaring demands for food, timber, and housing, have led to the destruction of the natural abode—the forests of Gujarat—of much of the beautiful Indian wildlife.

More than 485,000 hectares of the Ponderosa Pine forests in the southern Sierra Nevada of California are diseased as a result of air pollution, while approximately 25% of the area of Sequoia-Kings Canyon National Park receives enough oxidant air-pollution to elicit symptoms of smog injury on Ponderosa Pine, the dominant mid-elevation tree.

In 1983 we re-examined four permanent study plots that had been established in 1974–75. Smog symptoms on current needles in 1983 occurred on 23.8% of the trees compared with 14.5% only in 1975. Second-year needles had 60.7% showing symptoms compared with 44.2% in 1975. Less than 0.5% of the trees retained 6-years-old needles, and 21% had only 2 years of needle retention. Mortality attributed to air pollution was observed.

Insect control programmes sometimes include environmental modification techniques such as diking and drainage. The impacts of such techniques are not often known or assessed. As a telling example having wide implications, we present an analysis of impacts in a small estuary which has been subjected to both diking and ditching—primarily for mosquito control.

The major impacts stem from katteklei formation. Desiccated salt-marsh sediments produce acidified leachates which result from oxidation of pyrites. Lowered pH and high (acid-mobilized) aluminium concentrations both surpass levels that are known to be toxic to aquatic fauna. Fish and invertebrate communities in the basin are impoverished, and important commercial species such as American Eels and Alewives are heavily decimated. The acid-tolerant mosquito Aedes cantator thrives, however. Thus a natural system of substantial economic and aesthetic value has been inadvertently devastated through application of unnecessarily harsh as well as, in this case, ineffective mosquito control methods. Their use should be re-evaluated for similar impacts wherever such application has been carried out or is being contemplated.

Nicaragua is the largest (geographical area) country in Central America, but has the lowest population per hectare. For the last half-century its rich natural resources—timber, fruits, and minerals—were exploited by North American and European corporations without any regard for basic ecological principles. Furthermore, early in the 1950s, cotton was introduced and became the main source of foreign exchange. This led to massive use of pesticides, and construction of pesticide manufacturing plants, causing disastrous pollution by mercury of Lakes Managua and Nicaragua. It also forced migration of thousands of local subsistence farmers from the lowland cotton-producing areas to the hills where the farmers' ‘slash and burn’ techniques exacerbated the damage already done to the forests by foreign companies.

The paper starts with a report on the growing predominance of aquatic weeds of the genus Salvinia in the waterbodies of the world. The various ways in which Salvinia molesta, particularly, causes pollution and depletion water resources are then reviewed, as are the attempts made so far to control and eradicate Salvinia through chemical, biological, and mechanical, means. It is shown not only that these attempts have failed to achieve their purpose but also that there are possibilities of environmental backlashes being caused by the introduction of chemicals or bioagents into the environment. The importance developing environmentally safe methods of utilization Salvinia has been stressed, so that the cost of mechanical removal of the weed can be offset by the profits earned through its utilization.

Four selected reserves in Jordan have been studied to find out the effect of conservation on wildlife. These reserves are: Shaumari in the eastern desert; Surra in the Irano-Turanian region in the north of Jordan; Dab'aa in the Irano-Turanian in the southeastern part of Jordan; and Al-Fugaug in the Mediterranean region in the south of Jordan. The four reserves are representative of the three major biogeographical regions represented in the country.

Using the quadrat method of survey, the vegetation height, cover, phytomass, diversity, and total number of macrophytic species, were statistically analysed. The results obtained show that the values of the factors studied tended to be 2–3 times as much inside as outside the fence in the unprotected area.

These reserves were not subjected to any special treatment, merely being fenced and protected under natural condition without any human interference such as spreading of seeds, irrigation, fertilization, or any other anthropogenic factors.

The following recommendations are offered in order to protect wildlife: foundation of reserves for wildlife protection; increasing well-planned rangelands and grazing areas for meat production; implementation of the laws against offences; improvement of the rangelands through research and by using fertilizers or nodular Bacteria associated with leguminous plants adapted to dry conditions; increased water research in dry areas in the hopes of producing irrigated rangelands; marginal lands with a low rainfall must not be used for cultivation; scientific research is needed to determine the carrying capacity of rangelands in different regions of the country; development of new methods of animal feeding to decrease the grazing pressure on natural rangelands; prohibition of hunting for at least five years; and finally, intensive information and publicity through the different media should be given out to educate the public and make them aware of the urgent need to protect wildlife and make proper use of it.

Widespread agricultural burning during the dry season in the Pacific watershed of Panama is an important ecological phenomenon. During that time over 10% of the land surface (woodlands and savannas) is burned annually, with the resulting production of large amounts of charcoal. The major portion of the charcoal remains on land, but 5% is mobilized by river runoff and winds to the sediments of the Gulf of Panama.

The aeolian transport of particulate charcoal by the north-easterly Trade Winds has been monitored by dry-deposition and aerosol paniculate collectors. During the burning-season, atmospheric charcoal concentrations in rural Panama can be similar to urban concentrations in North America or Europe. More than 60% of the charcoal aerosol mass was carried as fine particles (< 2 urn diameter), suggesting that long-range transport is possible.

Dry-deposition fluxes, which are positively correlated with the areal extent of land that is burned, are more than an order of magnitude less than the charcoal fluxes to the uppermost near-shore sedimentary deposits in the Gulf of Panama. This implies that aeolian transport is not the principal mechanism of charcoal mobilization to these sediments. The extremely high runoff per unit area in the Gulf of Panama watershed is probably responsible for the predominance of continental runoff as the charcoal transport mechanism in the region.

Being relatively indestructible, charcoal can also be used as a tracer for past burning activities. Sediment box-cores have been recovered from the Gulf of Panama, and Pb-210 geochronologies were utilized to determine sedimentation rates. The charcoal particles were isolated by chemical methods and their fluxes, size-distributions, and morphologies, were analysed. The relative uniformity of these measurements in the marine sediment geochronologies indicates stability of burning patterns in central Panama during the last two centuries.

The main pelagic ecosystem of Lake Kivu in Central Africa is about to fall victim of a manipulation that took place a quarter of a century ago.

An experiment to suggest a technique for rehabilitation of a hard-limestone quarry floor in northern England was carried into its seventh year (see also Dixon & Hambler, 1984). The stress-tolerant grass Festuca rubra var. fallax Hack, cultivar Cascade proved suitable as a primary colonist, especially when sown onto rubble treated with a powdery manure derived from sewage. The community so produced was composed mainly of F. rubra and mosses, their proportions varying reciprocally with time but remaining approximately stable in a series of summer estimates of percentage cover.

The dry-weight per unit area of this vegetation, and that of other experimental sets, did not increase between the third and sixth years of the experiment. The organic content of the developing soil, however, increased considerably. Trifolium repens, where sown with the grass, had no obvious ecological impact, although its improved performance on Rabbit ‘middens’ indicated the general nutrient deficiency of the site.

A net flow of immigrant flowering-plants into the experimental site slowed down by the seventh year. Limestone grassland species arrived but the most abundant species were ruderals. All of the potentially large ruderal species failed to attain their full competitive potential, as did F. rubra. The community dominated by F. rubra and mosses proved unfavourable for the establishment of both Poa annua and Epilobium angustifolium— the latter being regarded as a particularly undesirable weed in this context.

The concept of visual acceptability was applied as a measure of the success of each sowing/treatment combination; the most successful might be recommended for rehabilitation of a worked-out limestone quarry.

Salvinia molesta, an aquatic weed native of Brazil, entered the floodplain of the Sepik River in Papua New Guinea in the early 1970s. It caused great distress to the local people by increasing exponentially to form thick mats covering many lakes and channels. A beetle from Brazil, Cyrtobagous salviniae, was established in one lagoon in 1982 and over the next 2 years 900,000 adults were redistributed manually among another 130 lagoons and lakes. Rates of beetle population increase (r) were close to 0.042 adult per adult per day in most lagoons. Local dispersal occurred when population densities reached 15 adults per kg of the Salvinia, damaging between 70% and 90% of Salvinia buds. Feeding by adults and larvae of the beetle caused entire mats of Salvinia to turn brown, die, and sink, but no deleterious changes in water quality were observed.

The time taken for beetles to spread throughout a lagoon and for the weed to be controlled was generally 12–18 months, depending on the area of the Salvinia mat, its thickness, and its mobility when blown by the wind. Herbicide was used to aid establishment of the beetle at one site by thinning a thick mat which had been colonized by sudd vegetation. An equilibrium appeared to be reached with the Salvinia present at < 1% of its former populationdensity.