Our Biosphere, the only one known to exist, is under attack by various factors. Major culprits amongst these include fossil-fuel-produced air pollution, acidic precipitation (acid rains), and CO2. As we run out of petroleum and natural gas, the question becomes: what should the new energy-system be, so that the damage to The Biosphere and life can be stopped? In view of the rapid depletion of the main energy sources of the present, the fluid fossil-fuels, this paper analyses the various primary energy-options (such as coal, breeder reactors, fusion reactors, and solar energy), and also considers such possible energy-carriers as synthetic fossil-fuels and hydrogen. In this analysis, the environmental effects of various options are considered both qualitatively and quantitatively.

It is concluded that the Hydrogen Energy-system is the most efficient and economical energy-system possible, and that it results in the environmentally most compatible and permanent energy-system when coupled with solar energy as the primary energy-source. It is important now that this information be disseminated among the public in general, and environmentalists in particular, so that the implementation of the solar-hydrogen economy can be started without delay, in order to minimize any further damage to The Biosphere and its living components.

The presence of water beneath the High Plains of Texas was widely known of by the first decade of the twentieth century, but it could not be abstracted economically until efficient pumps and engines were developed in the 1930s. Irrigation on the High Plains expanded rapidly during the late 1940s and early 1950s. At this time most people believed that the underground water-resources in the Ogallala Aquifer were limitless, and this led to the belief that water conservation measures were unnecessary. Given the perceived abundance of water, it was felt that control over the resource should reside at the local level and not be subject to the constraints of state or federal authorities. By the late 1950s and early 1960s, as well-water levels declined, it became apparent to a growing number of farmers that the reserves of the Ogallala Aquifer were finite and that they were being depleted at a rapid rate. This led to the voluntary introduction of water conservation techniques of which perhaps the best example was the spread of sprinkler irrigation.

Even more important, however, was the realization that if large-scale irrigation on the High Plains was to continue into the twenty-first century, it would only be able to do so on the basis of imported water, rather than by extraction of water from the Ogallala Formation. This seems to have dramatically changed the attitude of the local farmers— from a belief that the State had no part to play in water-resource management on the High Plains, to one in which the State is regarded as almost having a duty to supply the water needs of all its citizens. It is not suprising, therefore, that the farmers of the High Plains pressed strongly for the adoption of the Texas Water Plan in the mid-1960s. One of the main objectives of the Plan was to provide water from the Mississippi drainage basin via a major aqueduct through northern Texas to the Great Plains. Although the basic structure of the Texas Water Plan was accepted as a flexible framework for developing the water resources of the State in the late 1960s, it became obvious in the 1970s that the citizens in other parts of Texas were not willing to commit themselves to a massive water development scheme of enormous cost without its being widely felt to be absolutely essential.

By the early 1980s, many of the farmers of the High Plains had accepted that the State of Texas might not be willing, or even able, to supply the full water-needs of all its citizens and in particular the high irrigation needs of northwest Texas. Over the last few years, rising energy-costs have meant that it has become increasingly expensive to pump water from the ground, and this has forced farmers to employ water-conservation measures which in future may lead to less and less water being used—which in turn will permit the resource to be utilized for a prolonged period. In the long term, though, it does seem that increased emphasis will have to be placed on a return to dry-farming on the High Plains—such as alone existed before the 1930s—and that the irrigation boom of the late twentieth century will have been a temporary land-use phenomenon lasting for only a few decades.

The Doon Valley, in the foothills of the Himalayas in the State of Uttar Pradesh in India, has become the centre of major public-interest litigation in the Supreme Court of India. The conflict is centred around the utilization of the rich limestone deposits located in the Mussoorie Hills in the northern part of the Valley. The Mussoorie Hills receive an annual rainfall of some 2,000 mm, which is the second highest in North India. There is a very good water resource in the Mussoorie Hills, which is obviously connected with the water-holding capacity of the limestone belt.

For the operators of the limestone quarries, the best use of the high-grade limestone deposit lies in its physical extraction for commercial and industrial use. For the residents of the Valley, however, the best use of the limestone belt lies in its in situ functioning for the stabilization of soil and water resources. Damage to the stability of the hydrological balance of the Valley means damage to all other economic activities which, directly or indirectly, are dependent on the water resources in the Valley. These include agriculture, horticulture, tourism, animal husbandry, and knowledge-based industries etc. that together provide livelihood to the vast majority of the residents of the Valley.

The paper analyses the ecological background of the conflict. It evaluates the negative externalities of limestone quarrying in Doon Valley that damages perennial economic activities such as agriculture and tourism. The official steps taken by the State Government to control the ecological damage from quarrying having proved inadequate, the residents of the Valley looked for justice and the right to survival from the Supreme Court of India.

Wildland fire management directly affects the forces of natural selection to which plant taxa become adapted. Changes in a fire regime will often result in changes in the relative abundance of particular species, and may cause the extinction of some of them. Life-history characteristics are important indicators of adaptation to recurrent disturbance, such as may be produced by fire. The incorporation of these characteristics in a computer simulation allows of the projection of species abundance under different fire regimes.

Through prescribed burning and fire suppression, fire interval and fire intensity can be controlled to some extent. The fire intensity for given sets of fuel, site, and meteoro-logical conditions, representing given fire-intervals, is calculated with the use of a fire behaviour computer simulation. These results are incorporated in computer simulation of the demographic competition of the five dominant shrub species of coastal sage-scrub in the Santa Monica Mountains of southern California: Artemisia californica, Encelia californica, Eriogonum cinereum, Salvia leucophylla, and S. mellifera. The model incorporates resprouting proportions, seedling establishment, and growth, and assumes survivorship rates in simulating scramble competition for space. Foliar cover-values of the five species are projected for nine different fire regimes. Short fire-intervals of the order of 10–20 years, such as might occur under a regime of prescribed burning, may eliminate or greatly reduce some species, whereas longer intervals allow the maintenance of a more diverse community especially of shrubs. Fixed and variable interval-lengths do not produce appreciably different results.

This study suggests that prescribed burning at 10–20 years' intervals should not be used indiscriminately to reduce wildland fire hazard in southern California. The fire intervals that will reduce the hazard, may eliminate some dominant native shrub species. A ‘natural’ fire regime which would maintain the natural vegetation while constituting only a minimum hazard to homesites may, unfortunately, be mutually exclusive goals in the coastal sage-scrub of southern California.

The Soviet Union's Crimean peninsula in the Black Sea has the northernmost occurrence of Mediterranean-type climate and vegetation, particularly in its narrow southern coastal strip which has been almost entirely developed for the tourist and health resort trade. Three inland mountain ranges and their vegetation, both forest and steppe, exert a protective influence over the microclimates of the coast and are thus being extensively studied by scientists at the Ministry of Agriculture's Nikita Botanical Garden and at Simferopol State University. Inland of these ranges lies an expanse of former meadow-steppe that is now under cultivation.

In order to protect and study the high concentrations of remaining native and relict taxa of flora and fauna of the peninsula, three Nature preserves have been established on it–two in the mountain zone and northern coastal islands, and one along the southern coast and adjacent lower slopes. Here human access is restricted while long-term ecological studies are undertaken.

The Nikita Botanical Garden is involved in both conservation and exploitation of natural resources, and in improving health conditions of the resort. These tasks are integrated through a programme of mass seed propagation and ecological studies of wild-growing plants, the results of which are then used in landscaping the resort zone and producing industrial plant materials.

The Communal Lands—occupied by peasant farmers—of the upper catchment of the Sabi River (which drains the southeastern portion of Zimbabwe) are severely deforested, overgrazed, and eroded. Siltation of the river channel has increased the risk of overbank flooding at a downstream irrigation scheme, and a rise in annual outflow from the catchment over the last three decades has additional implications for irrigation development, as well as for the availability of ground-water reserves in the areas of dryland peasant farming.

In a study area within one of the Communal Lands, the average rate of soil loss from fields of gentle slope is estimated to be such that the next generation of peasant farmers will be unable to achieve crop-yields above a very low ‘subsistence’ level. The degraded environment is the inevitable consequence of the expansion of a primitive system of cultivation—in a region of low inherent potential for crop production—under the pressure of rapid population growth. While the peasants are aware of many of the consequences of their exploitative methods of land-use, and recognize the importance of basic conservation measures such as erosion-control terraces, they generally feel that remedial action is beyond their means.

The effective implementation of available technical solutions to the deterioration of the land resources, will depend upon the provision of greater financial incentives for intensified production, as well as upon more positive political influences, than exist at present. The eventual stabilization of the situation is achievable only if population growth is reduced; but much might be done to improve production, and promote conservation, through field research into appropriate farming systems for peasant agriculture in the Sabi catchment and similar environments.