bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Population and Environmental Problems
Authors: Ehrlich Paul R. 
Published: August 2009

Human population growth is clearly outstripping the possibilities of increasing the supply of food and other prerequisites for satisfactory existence. Already, with around four thousand million people on Earth, the race appears to have been lost by agriculture. The prospect of doubling this population by shortly after the turn of the century is bleak indeed. It is the belief of many, however, that zero population growth will be reached earlier by a catastrophic increase in the number of deaths—most probably from starvation. This also bodes ill for conservation; for as people get more and more hungry, their behaviour towards wildlife and what remains of the natural environment is going to become more and more reckless. The destruction of both wildlife and its habitat may be expected to extend to quite devastating proportions, which will require understanding action in both over- and under-developed countries to counter with any degree of success.Man is inexorably changing the face of the Earth and weather patterns in directions which could have all manner of widespread ill-effects, and already have had some catastrophic local ones. Yet more and more of the world's productive lands are being paved with concrete, and the productivity of even wider areas is being permanently lost through erosion and laterization following the clearing of forests and other binding vegetation. Simultaneously, many strains of crop plants are being lost which are essential to humanity because they enable plant breeders to develop new agricultural varieties to help keep abreast of changes in pests and weather, and to raise production levels.
Hazards of Nuclear Fission Power and the Choice of Alternatives
Authors: Edsall John T. 
Published: August 2009

Nuclear fission reactors are widely regarded as the chief energy source of the future. This article holds that the hazards of such reactors, in comparison with other prospective energy sources, are unacceptably high. The biological effects of ionizing radiations, as analyzed in the recent BEIR Report (1972) of a committee of the U.S. National Academy of Sciences, are briefly reviewed; the effects include genetic mutations, induction of cancer, and developmental abnormalities. Hazards are encountered at many stages in the process of nuclear power production: in the mining and processing of uranium, in the design and operation of the reactors, and in the handling, shipping, and storage, of the huge quantities of radioactive wastes produced by the reactors. Grave questions have been raised concerning the safety of the emergency core-cooling systems of present reactors; and the planned breeder reactors, which will contain great quantities of plutonium-239, are likely to be even more hazardous. Storage of radioactive wastes, away from all risks of environmental contamination, in order to be acceptable must be secure for about half-a-million years. No place on Earth has yet been found for which such safety can be guaranteed. Hazards of theft, sabotage, and war, are formidable threats to the future of nuclear fission power.Use of fission power is not compulsory; present supplies of coal are adequate for two or three centuries, though its mining and use will require drastic steps to protect the environment, thereby raising costs. Alternative, and far less dangerously polluting, sources of large-scale energy production exist or can be developed: notably solar energy and probably nuclear fusion, where intensive research gives high promise of adequate systems for large-scale energy production within 20–30 years. Geothermal energy, though more limited in amount, is also promising. Great savings can also be made by reducing the extravagant use of energy, especially in such countries as the United States; and various conservation measures are indicated.
Conservation Problems and Progress in Equatorial African Countries
Authors: Curry-Lindahl Kai 
Published: August 2009

The conservation movement in Africa during the 1960s has worked along many front lines. Failures and successes have been registered. As a whole one may say that there has been tremendous progress for conservation in Africa when the situation in 1974 is compared with what it was in 1960, but nevertheless at present there are still more productive waters and land areas that are being destroyed than are being saved or restored. The conservation fight has to go on, and it is a battle against time and human misconceptions. Particularly are there some countries in which the values of menaced Nature have been considered to be of such exceptional importance that special efforts have been undertaken within the meagre means available to the international organizations most concerned.The present paper constitutes a review of significant environmental conservation measures, proposals, and failures, in various regions and countries of equatorial Africa. It is hoped to follow with a similar treatment of northern and southern Africa. Emphasis will be laid on national parks and nature reserves, because at present it is particularly in this field that African states show their conservation consciousness. It is to be hoped that the time will soon come when the necessity for conservation, management, and wise utilization, of renewable natural resources, will be fully realized also outside the national parks and equivalent reserves.
Nuclear Fusion Power and the Environment
Authors: Hirsch Robert L. , Rice William L. R. 
Published: August 2009

The physics problems remaining to be solved to achieve practical fusion power by magnetic confinement techniques are believed to be well posed and soluble. A programme plan recently developed in the United States calls for progressively larger plasma confinement experiments to address these physics questions in line with a serious programme in fusion power engineering. Implementation of the plan is expected to lead to the first production of power from a deuterium–tritium-fuelled system in 1980. Thereafter, three progressively larger experimental electrical power reactors are planned, leading to fusion power commercialization in the later 1990s.The environmental characteristics of fusion reactors have been estimated by analyzing conceptual reactor designs. It is projected that the only volatile radioactive material in a fusion power-plant will be the tritium fuel. Analyses indicate that tritium leakage can be held to very low levels and accordingly should not pose a significant environmental hazard.Careful selection of the materials of construction of a fusion reactor core will minimize radioactivity induced by neutron activation. This activity will be nonvolatile, and it can be isolated from the environment by the use of existing techniques. Because this induced activity is short-lived, it does not represent a long-term storage problem.Anticipated thermal efficiencies of fusion powerplants range from present-day levels (30–40%) using standard conversion systems to about 50% when more exotic techniques (such as liquid-metal topping cycles) are utilized.
The Relationship Between Colliery-waste Particle Sizes and Plant Growth
Authors: Down Christopher G. 
Published: August 2009

Seed germination and dry-weight production in Lolium perenne were examined in relation to growth on 12-years-old colliery waste separated into seven size-fractions. The size-range was from more than 4,000 μ to less than 125 μ, and the growth period was up to 30 days. Germination percentages after 6 days generally increased with decreasing particle-size, as did dry-weight. Shoot : root ratios also showed an inverse relationship with particle size.After 30 days there was no distinction between dryweights on different particle sizes, except that on the largest fractions it had been found impossible to keep the plants alive. Problems of water-holding capacity are discussed, and the significance of soil particle-size in revegetation work is examined, it being concluded that an admixture of small particles is important for water retention and plant growth.
Land-building and Stabilization by Mangroves
Authors: Carlton Jedfrey M. 
Published: August 2009

Covering broad areas of tropical shorelines are unique plants known as mangroves, which exhibit several structural and physiological modifications to the saline environment—especially in their root systems. Prop-roots and pneumatophores, two obvious modifications, allow mangroves to play a role in coastal geomorphology, either as land-builders or as stabilizers of substrates derived from classical sedimentation processes.Current data show that: (1) Provided with proper substrates, mangrove seedlings can be raised in the laboratory for later planting in the field, although on exposed beaches success ratios may be low. (2) Larger mangrove plants (1.0–5.0 m in height) may be transplanted with relative ease and appear to succeed with few or no mortalities resulting from the techniques used. (3) Pruning of mangroves appears to be a successful method of mangrove control, allowing their utilization for stabilization around housing developments. (4) Fossil evidence for mangroves as shoreline developers is suggested by the discovery of a fossil mangrove reef off the Miami, Florida, coast. However, submergence of near-by mangrove areas has occurred, as evidenced by sea-grass beds growing above buried peat in the bay bottom. (5) Black Mangroves may be more useful than Red Mangroves as shoreline stabilizers due to their cold-hardiness, ability to tolerate disturbed substrates, and rapid production of pneumatophores. (6) Insect and isopod damage to mangroves has been documented, and it has been suggested by several research workers that such damage may lead to increased erosion of coastlines in many areas of southern and central Florida. In addition, boring activities in Red Mangrove seedlings may result in decreased numbers of seedlings being available for new mangrove growth and colonization. (7) Mangroves have been suggested for use as stabilizers of substrates in conjunction with planned filling and sea wall construction.
The Impact ofAcanthasteron Corals and Coral Reefs in the Eastern Pacific
Authors: Glynn Peter W. 
Published: August 2009

The movement of surface currents and the availability of coral prey are probably not responsible for the discontinuities in the distribution ofAcanthaster(the Crown-of-thorns Starfish or Sea-star) in American waters. Temperature and salinity conditions are critical in development, and it is possible that these parameters are effective locally, for example in the Gulf of Panamá. There is a strong possibility that continuing field work will show thatAcanthasterhas a significantly more widespread distribution in the eastern Pacific than is currently known.AdultAcanthasterand several species of coral prey exhibited an unusually high tolerance to varying conditions of temperature and salinity. The possibility of step-wise colonization to new areas, mediated by resistant adult populations that can become established during favourable seasons, should be considered in any plans to alter the existing freshwater canal in Panamá. For introductions can be environmentally dangerous.The highest population densities ofAcanthasterso far observed in the eastern Pacific, 1 individual/40 m2to approximately 1 individual/100 m2, are comparable to population sizes in the Indo-Pacific region that are not considered to have a serious impact on coral communities. Coral destruction byAcanthastercan be significant in certain limited areas, but is usually less than that caused by other corallivores.An analysis of coral community structure in relation toAcanthasterdensity failed to show a significant correlation with (a) number of species, (b) number of live coral colonies, (c) species diversity (H'), or (d) species evenness (J').Prey preference data indicate thatAcanthasterselectively destroys rare corals. Replacement of rare, predated corals by fast-growing species (Pocilloporaspp.) has been observed in the field, showing thatAcanthastercould have a negative effect on species diversity.
The Euphrates River—an International Problem of Water Resources Development
Authors: Beaumont Peter 
Published: August 2009

The watershed of the River Euphrates lies within the boundaries of the present-day states of Turkey, Syria, Iraq, and Saudi Arabia. Almost 90% of the runoff from the basin is generated within the highlands of eastern Turkey as the result of snow-melt occurring during late spring and early summer. At this time, flood levels are usually reached along the whole length of the River.The former inhabitants of the floodplain lands of Iraq utilized the waters of the River Euphrates for at least 6,000 years. By so doing, empires dependent upon irrigated agriculture flourished and then decayed, leaving behind spectacular ruins practically throughout Mesopotamia. Until the time of the Second World War, Iraq was the only country within the Euphrates basin that made large demands on the water resources of the River. Since that time, Iraq's demand has continued to increase, resulting in average water withdrawals of over 16,000 million m3/year during the 1960s. This figure represents about 45% of the average annual discharge of the Euphrates into Iraq.Since the mid-1960s, both Syria and Turkey have planned major dam schemes to utilize the waters of the Euphrates. The Tabqa Dam in Syria, and the Keban Dam in Turkey, have already been constructed, and Turkey has planned other major hydraulic works along its section of the River. When the irrigation projects associated with these schemes are in full operation towards the end of the century, it seems that the likely demand for water will be in excess of the available flow of the River.The country which is likely to suffer most as a result of this is Iraq, owing to its situation in the lowest part of the basin. Already, diplomatic relationships between Syria and Iraq have been severely strained as the result of disagreements about the allocation of the water resources of the River Euphrates. In future, it seems possible that such disputes will continue to occur, and perhaps also to become of increasing severity as both Turkey and Syria begin to use large proportions of the available riverflow for irrigation. The only permanent solution to the problem would seem to be the establishment of an international body to supervise the just allocation of the water resources of the Euphrates between Turkey, Syria, and Iraq. At present it seems unlikely that a lasting agreement will be reached between the three countries.
Phytoplankton of an Acidic Lake, and Its Responses to Experimental Alterations of pH
Authors: Yan Norman David , Stokes Pamela 
Published: August 2009

Carlyle Lake is typical of north-temperate Canadian Shield lakes both morphometrically and in its thermal and oxygen structure; however, the Lake is chemically unusual. Input of acidic melt-water in the spring of 1974 depressed the pH of the Lake to 4.5. The buffering capacity of the Lake has been reduced to such a degree that summer pH levels are about 5.0.Despite this relatively high acidity, the biomass of the phytoplankton community is not low for an oligotrophic circumneutral lake. Although some evidence exists that phytoplankton community biomass is reduced in lakes of pH about 4.5 or below, no such reduction was observed in Carlyle Lake. However, as the numbers of phytoplankton species are reduced when lake pH levels fall below about 5.6, it would appear that community diversity is a more sensitive indicator of acidification of lakes than is community biomass.
Damage and Recovery of Tundra Vegetation
Authors: Webber Patrick J. , Ives Jack D. 
Published: August 2009

This paper makes a series of broad recommendations concerning the understanding of damage and recovery of tundra vegetation. It deals primarily with arctic vegetation and with principles rather than specific recommendations or instructions for restoration. Actual procedures for restoration or revegetation, although practised, are still in their experimental stages.Despite this lack of established methods in tundra vegetation restoration, much can be done to help offset some of the worst effects of the present surge of economic development that is occurring in certain sectors of the Arctic. First, a rational assessment of types and extent of damage that is likely to accrue from different kinds and degrees of impact should be attempted, based on existing experience and theory. This should be accompanied by similar assessments of degrees and rates of recovery.
Applying Island Biogeographic Theory to an East African Reserve
Authors: Miller Ronald I. 
Published: August 2009

The isolation of nature reserves by encroaching civilization may provide significant changes in the structure and composition of protected animal communities. Recent models from applied island biogeographic theory provide a means of predicting the possible effects of isolation in the large-mammal community in the Mkomazi Game Reserve of northern Tanzania. A decrease in the number of large-mammal species inhabiting this preserve is predicted by all the models.The dynamic interdependence of the large-mammal communities of East African reserves is vital to their survival and yet is especially vulnerable to disruption from surrounding human activities. Knowledge of the effects of increasing isolation on the complex community interactions among the component ecosystems in East African reserves, will enhance conservationists' ability to minimize extirpation pressures in this region.
The Environmental Impact of Agriculture in Ethiopia
Authors: Kuru Assefa 
Published: August 2009

The basis of the physico-social pattern in Ethiopia, indicated above, may be summarized as:(a) The main features of the country are formed by volcanic activity;(b) There exist a lot of fragmented highlands with a great range of altitude, climate, and vegetation;(c) The content of organic matter in the soils is very low on the eroded lands, greatly limiting their ability to retain water;(d) There exist a wide variety of cultural patterns and numerous spoken languages;(e) There are very severe erosion hazards and continuous deforestation activities;(f) There is a custom of uncontrolled grazing, and livestock are not limited according to the carrying capacity of the land;(g) There are constraints in the distribution and quality of water that is available for domestic supplies, livestock, and crops;(h) From ancient times there has been no substantial improvement in farming tools and implements;(i) There is little government investment in development work in general;(j) The importance of a conservation programme for a wide range of natural resources is not felt/realized by the government;(k) There is no emphasis on erosion control and forestry management—even by the regional development projects of the minimum and maximum package projects financed by the World Bank and other bilateral international cooperations;(l) There are big constraints in matters of education and agricultural extension services; and(m) The mountainous terrain and deep gorges have made communication difficult and expensive.As a result of the above, the overall development network does not at present provide an adequate access to support a productive and continuous agriculture.
U.N. Conference on Desertification, in Retrospect
Authors: Biswas Margaret R. 
Published: August 2009

The United Nations Conference on Desertification was the first occasion on which the nations of the world turned their concerted attention to the need for a comprehensive plan to halt and reverse desertification. The global annual loss to desertification is in the order of 60,000 km2. It is Man's action that degrades the land by misuse as he seeks to wrest a living from fragile ecosystems. A change to a more arid climate could be another cause, but no firm evidence is available that the climate is so changing. The Conference concluded that both the causes of desertification and the technical solutions to combating it are known. The key to combative measures is to be found in proper land-use. If desertification is to be brought to a halt by the end of the century, considerable financial resources will, however, be necessary.The paper includes a comprehensive summary of the unpublished statements of the various national governments and some international agencies regarding their problems, an analysis of the findings of the Conference, and a brief discussion of action taken since its conclusion.
Plant Life and Desertification
Authors: Went Frits W. , Babu V. Ramesh 
Published: August 2009

There are numerous instances where, through injudicious use, Man has contributed to desertification of the agricultural environment by increasing the aridity and decreasing the ability of the soil to support vegetation. This may come through erosion, even in areas with very high rainfall (e.g. Amazonia). But in many arid regionsdedesertification has occurred under the influence of Man (e.g. Imperial Valley in California, Hungry Desert in Uzbekistan, 90-Miles Desert in Australia).However, under certain conditions, such as those of fog-drip, an irreversible desertification can be caused by removal of the original vegetation (e.g. Central Chile).Dew may be an important source of water for plants even in deserts, where there is a shortage cf liquid water for plant growth.
Gulls and Aircraft
Authors: Solman Victor E. F. 
Published: August 2009

Birds, struck during flight by fast-moving modern aircraft or getting ingested in jet engines, cause numerous serious accidents of which some involve human deaths. Gulls of various species are the birds involved in a considerable proportion of these accidents due to bird-strikes.Gull-strikes of aircraft in flight may be expected:1. When there is a chronic attraction such as a concentrated worm or insect population, a high mouse population, or some other biological attractant;2. When there is lack of care in disposal of food-wastes;3. When drainage on an airfield or on flat-roofed buildings is not properly designed or is not functioning well; or4. During the early autumn when large numbers of inexperienced, immature gulls are in flight.
Some Crucial Issues of Our Time
Authors: Guppy Nicholas G. L. 
Published: August 2009

In the U.S.A. and other advanced countries, tribal peoples, together with other minorities, receive protection, their land-rights are respected, and reparations are being made for past violations. In the Third World there may be protective laws but, in practice, these are commonly ignored because it is profitable to do so. As a result, there is nothing to stop the present world-wide destruction of the environment in undeveloped regions— particularly of tropical forest—and the accompanying sociocide.At present rates of destruction, pratically all existing natural tropical forests will have been cleared in 15–20 years' time, and catastrophic consequences are predicted. It is important to start using substitutes for raw materials emanating from forests—right now, while there still remain large forests and wild areas which can be saved. To aid this process it is proposed that a worldwide organization of timber producers should be formed along the lines of OPEC—to raise timber prices to true, i.e. replacement, costs—and that similar organizations should be formed for other raw materials. Such organizations could reduce environmental destruction without loss of income. Simultaneous with this, existing laws to protect tribal land-rights must be more vigorously enforced than hitherto, and new laws and institutions must be created where necessary to help slow the pace of destruction of tribal environments and societies.