bluuebunny/crossref_metadata_2025_split huggingface dataset:
Restoration of Arid and Semi-arid Ecosystems in Afghanistan
Authors: Hassanyar Amir S. 
Published: August 2009

Barren, desert-like environments have been created over large areas in Afghanistan, and various degrees of desertification can be seen especially in the southwestern plains. Extensive overgrazing, frequent drought, and unwise land-use, have initiated processes of local desertification also elsewhere in Afghanistan.The first step in the restoration of depleted vegetation is to correct the improper uses that have been responsible for these conditions. Improper grazing practices of rangelands are a primary cause of reductions in the productivity of arid and semi-arid ecosystems in Afghanistan.The second step in restoration is to prepare a detailed revegetation plan. The following maps and information are needed: (1) a vegetation-cover map, (2) a soil-series map, (3) a topographic map, and (4) baseline data on climatic conditions. The vegetationcover map identifies the plant biomass potential and the species that might be suitable for revegetation. The soil-series map is accompanied by a description of the physical and chemical features of the topsoil and subsoil along with an assessment of the general herbage production potential. The topographic map helps with species selection and planting methods. The climatic parameters assist in determining the season of planting and any need for drought-resistant species to be planted.
Seasonal Variation of Trace-metals in the MusselMytilus californianus
Authors: Ouellette Thomas R. 
Published: August 2009

Natural seasonal variations of the whole-body concentrations of six trace-metals inMytilus californianuswere determined by sampling fortnightly (‘biweekly’) for one year in a relatively pristine environment. Mussels of similar size were collected from a single mussel-bed, and within a discrete tidal range, in order to reduce variability unrelated to the availability of metals in the environment. The accumulation of iron, aluminium, and manganese, and to a lesser extent lead, was directly related to the input to inshore waters of terrigenous materialviastorm-generated runoff and bottom resuspension during the winter months.Variations in the accumulation of copper appeared to be related to elevated concentrations of organic Cucomplexing compounds in the water-column both during the winter (e.g. humic acid, introducedviarunoff) and during upwelling (e.g. extractable organic material from decomposing phytoplankton). Increased accumulation of cadmium by mussels during the spring was directly proportional to increased surface nutrient concentrations, indicating that Cd is upwelled to inshore waters.Quantities of both Cd and Pb available to mussels during the Upwelling period appeared to be depleted by, and diluted within, the increased phytoplankton biomass present at that time. No relationship was observed between concentrations of any of the trace-metals analyzed and the reproductive condition ofM. californianus.
On the Role of Underwater Parks and Sanctuaries in the Management of Coastal Resources in the Southeastern United States
Authors: Davis Gary E. 
Published: August 2009

Aquatic resources in parks and reserves are not as adequately protected as comparable terrestrial resources. Thus the values of protected aquatic ecosystems as standards for comparison, reservoirs of genetic materials, and ‘emotional’ reserves, are apt to be greatly diminished.Even seemingly static ecosystems such as coral reefs are dynamic, changing dramatically in response to natural short-term environmental variations. Such ecosystems require protected natural areas as dynamic standards that will allow distinctions to be drawn between effects of exploitation or pollution and normal variation. Furthermore, fisheries harvests may reduce the size at which exploited species mature, and reduce the amount and variability of genetic material produced by exploited populations.The seven underwater parks or sanctuaries established since 1935 in Florida and the U.S. Virgin Islands exhibit wide variations in the degree of protection accorded to aquatic resources, a range being apparent from nearly complete protection in the first parks to be established to virtually no protection at all in the recently-established parks.The consequences of permitting consumptive uses of aquatic resources in parks and reserves need to be objectively evaluated. Unless these consumptive uses are severely curtailed or eliminated, the primary values of the parks and reserves may never be realized.
Incorporating Environmental Considerations into Planning
Authors: Engelmann Rudolf J. 
Published: August 2009

It is possible to produce environmental assessments in an efficient, economical manner by the careful advance specification of future information needs, the collection of the pertinent data into a single set of sectoral reports, and subsequent analysis of the information on a case-by-case basis as individual projects arise. The procedure for this, in six main steps, can be as follows:A development scenario is produced that is a description of the chronological sequence of economic, industrial, and agricultural, activities. The scenario is studied to identify potential issues and conflicts. A list of basic questions and more specific sub-questions that follow from the issues and conflicts is then derived. The data to answer those questions are then collected and organized into sectoral reports. Later, as each assessment need arises, these sectoral reports will be found to contain the information that is required. Finally, the assessment is produced from the sectoral reports and leads to a decision on which action is taken.The mechanics of the above procedure include: surveys of a wide range of information sources, each survey using sources which are appropriate to the step that is being taken; use of a standing core assessment group; use of common base-maps and formats; and well-planned interdisciplinary meetings.As well as producing assessments at short notice, the procedure can be expected to provide priorities for research, and eventually to lead to due insertion of environmental considerations into national planning during the planning stage itself.
Aspects of Water Pollution in Lake Naini Tal, U.P., India
Authors: Pant M. C. , Gupta P. K. , Pande J. , Sharma P. C. , Sharma A. P. 
Published: August 2009

The paper discusses certain microbiological, biological, and chemical, aspects of pollution in Lake Naini Tal, U.P., India, which is characterized by heavy input of domestic sewage and other organic pollutants. The most probable number (MPN) for coliform Bacteria varied from 0.59 × 105 to 3.61 × 105 per 100 ml, being highest in the monsoon season and lowest in spring. The water was alkaline in reaction throughout the period of study. The concentrations of dissolved oxygen showed high values near the surface and low ones in the bottom waters. BOD values always exceeded 6.0 mg/1. The concentrations of NO3−N and P04−P varied from 0.100 to 0.750 mg/1 and 0.018 to 0.153 mg/1, respectively. These concentrations are sufficient to cause blooming of certain phytoplankters on occasion. The values of NH3–N fluctuated from 0.033 to 0.422 mg/1, being highest in winter and lowest in the monsoon months. Among the metallic ions, the values of Pb and Mn were higher than permissible limits.The bottom sediments of the Lake were also found to produce toxic gases such as CH4, H2S, and NH3. Most of the carp fishes, such as Cyprinus carpio specularis, Tor tor, and Schizothorax spp., were found to be infected with Saprolegnia or other Fungi, or with trematodes. Certain phytoplankters (such as species of Microcystis, Anabaena, etc.), zooplankters (such as species of Bursaria, Spirostomum, Phillodina, etc.), and macrobenthos (including Tubifex tubifex, Limnodrilus sp., Chironomus plumosas, etc.), were found to be abundant. Macrobenthic species were absent from the profundal zone of the Lake, which showed all the important characteristics of a polluted water-body.
Regeneration Methods for Tropical High-forests
Authors: Kio Philip R. O. 
Published: August 2009

Changes taking place in the natural tropical forests are intricate, and the ecological processes which they entail are only gradually becoming understood. Human interference in these processes frequently leads to unforeseen consequences, silvicultural treatments being apt to be applied long before much is known about the characteristics of the constituent species and the particular successional phases on which treatments have been imposed.Perturbations create gaps of varying sizes. Both regeneration in the gaps and the latter's restoration to a state of equilibrium, depend on their size and the intensity of the disturbance. Deflected successions may occur in sensitive ecosystems whereby progress towards vegetational climax is permanently interrupted. In Africa, the human impact on the natural vegetation has been more severe and for a much longer period than in either the Amazon or in large areas of the Indo-Malaysian rain-forest.Apart from the limitations of existing silvicultural techniques for inducing regeneration and promoting growth, vital management decisions are commonly based on the results of regeneration sampling. But this traditional sampling technique does not make sufficient use of the indications provided by Iiocourt's ‘living space’ theory. However, modified procedures which can easily be undertaken and which assign more appropriate areas of occupation to individual seedlings, saplings, poles, and trees in the stand, provide more realistic estimates of the overall stocking. Though much damage is done to saplings and poles by the felling of large trees, the severity of damage is related more to the number of trees felled than to the basal area or volume removed. However, research into effects of alternative logging regimes (monocyclic versus poly cyclic) is required to resolve, for particular forest types, the issue of appropriate management/silvicultural prescriptions.On the basis of silvicultural research in Nigeria, tentative conclusions have been reached that the growth of a residual stand after exploitation can be accelerated by shelterwood treatments. In particular, climber cutting and opening of the canopy by poisoning are effective treatments in promoting recruitment of saplings and poles from seedlings, and their subsequent growth and survival. Controlled logging can be as effective as a poisoning operation to remove shade-casting, uneconomic emergents, and if substituted for such shelterwood poisoning could reduce the expense of implementing forest treatment.In forest management, account must be taken of differing capacities for growth between different species—especially in response to different silvicultural treatments. Thus in the experiments discussed, heavy poisoning promoted greater increments than selective poisoning, though the difference was not statistically significant.
Populating Israel's Mountains while Preserving Their Environmental Quality
Authors: Soffer Arnon 
Published: August 2009

At the beginning of the twentieth century, the Galilee Mountains were still practically a ‘closed system’, as a result of which the balance of land-use was more or less preserved. Rural settlements had then hardly developed, and stagnation of the few remaining mountain towns was observed. In general, the roads were unpaved routes, the economy served for subsistence only (based mainly on agricultural terraces), while most of the area was of forest or rocky ground serving as pasture.During the British Mandatory period, the Galilee Mountains area opened up slowly, and this process has increased ever since the establishment of the State of Israel. The Mountains are facing a tremendous increase in population as a result of natural local increase (mostly Arabs) and migration (mostly Jews). This excessive mountain population in Israel is an unusual phenomenon in comparison with other mountain regions in the western world, which have generally decreased in population though there, too, the equilibrium of land-use has been shaken—for instance in the Swiss Alps (Bugmann, 1980; Gallusser, 1980; Messerli et al., 1980), and in the Rocky Mountains of the United States (Kelly, 1980).
Biological Colonization of an Industrial Pond: Status After Two Decades
Authors: Rickard William H. , Fitzner Richard E. , Cushing Colbert E. 
Published: August 2009

The biological status of an isolated, man-made pond established in 1957 is described principally after its first 20 years of existence. The pond is located in the dry sagebrush region of south-central Washington (USA), and is colonized by Bulrushes, Cattails, and numerous Algae. Migratory waterfowl were the first vertebrate users of the pond; and with the establishment of shoreline plant communities and submerged macrophytes, the pond now provides nesting habitat for several duck species, American Coots, and Pied-billed Grebes. Use of the pond by large mammals is limited to visits by Mule Deer, Coyotes, and Raccoons. There are no Muskrats or Beavers in the pond. Turtles and Garter Snakes are not found in or around the pond but are present in the near-by Columbia and Yakima Rivers. The absence of these vertebrate animals is attributed to the isolation of the pond and the absence of connecting surface waterways between the pond and the regional watercourses. The only fish in the pond are Goldfish—presumably of artificial introduction.Some of the more sedentary pond organisms—aquatic arthropods, crustaceans, and snails—may have reached the pond in raw Columbia River water, or been transported as eggs externally attached to waterfowl, or possibly been voided into the pond along with avian faecal material.The pond contains low levels of industrially-derived radionuclides—especially caesium-137. Radiocaesium is mostly confined to bottom sediments, but is readily assimilated by biota and so appears in all trophic levels. Some of the societal concerns and research potentials associated with the pond are discussed with special references to food-chain and biotic transport mechanisms.
Modifications to Stream Channels in the Brisbane Metropolitan Area, Australia
Authors: Boughton Walter C. , Neller Ronald J. 
Published: August 2009

Knowledge is needed of the geomorphological characteristics of stream-channels in urban areas in order to manage the streams for recreation, biota conservation, environment enhancement, erosion control, and the discharge of stormwater runoff. This study is concerned with how urban streams in Brisbane have been substantially modified by many different human activities, and how the future behaviour of the channels is likely to be very complex because of the diversity and magnitude of these modifications.Major water-supply dams have been constructed on three of the streams, and some flood-detention storages are soon to be constructed on another. The earth embankment of the South-east Freeway fills the upper reaches of Norman Creek, and stormwater runoff is now carried in a man-made channel. Elsewhere in this catchment, flood-flows have been modified by culverts—where the Freeway and access roads cross the drainage channels, and where the Freeway embankment occupies a substantial part of the floodplain of the Creek.The construction of Brisbane Airport has already modified the tidal reaches of Kedron Brook, and the proposed redevelopment of the Airport will replace the existing modification with a major new floodway.Several of the stream-channels have been deepened, widened, and straightened, for flood-mitigation purposes, with 465,000 m3 of material removed from Breakfast Creek alone. Three of the stream-channels have been used as major sources of sand and gravel for building activities in the City. Flood characteristics of the streams appear to have been changed by increased runoff from impervious surfaces when these reached a critical threshold in the urban areas, and by increased velocities of flow in piped, lined, and other, artificial stormwater channels. Construction of new artificial channels amounts to some 15 km per year.The modifications which have occurred differ among the urban streams in Brisbane, and each stream requires individual study to assess the long-term effects of the changes. All of the streams reported on in this study have been substantially modified by human activities.
The Climatic Sensitivity of ‘Green Revolution’ Wheat Culture in Sonora, Mexico
Authors: Michaels Patrick J. 
Published: August 2009

A statistical model was developed to assess the effects of interannual climatic variability on wheat yields in Sonora, Mexico, where the high-yielding variety (HYV) agricultural ‘package’ was first developed. The approach taken was necessary because of the lack of suitable ‘dynamic’ formulations. The climatic terms in the model—transformed monthly mean temperature and precipitation values—explain almost 37% of the variance in the yield time-series, after allowing for the simultaneously generated base and trend values. This figure is somewhat less than that in similar formulations for North American wheat, where the climatic and yield data may be more reliable.The yields are most sensitive to preplanting moisture input, when the irrigation system is being recharged, and to March temperature, when fertilization can be reduced by heat. The yield response to these two variables was found to increase significantly as more HYV agriculture is adopted. Increases are over twofold for the precipitation term, and nearly threefold for the temperature variable.A variety of arguments suggests that the results truly indicate an increased climatic sensitivity in the yieldresponse, although the formulation is incapable of discriminating between sensitivities that are purely ‘genetic’, and those associated with the cultural practices which the genetic change allows to be established. When impacts upon the consuming population are considered, the distinction between the two becomes somewhat less important.
The Human Causes of Forest Depletion in Nigeria
Authors: Osemeobo Gbdebo Jonathan 
Published: August 2009

Human activities in Nigeria are not evenly distributed on the land surface, owing to marked differences in climatic, geological, demographic, and cultural, factors in different areas of Nigeria. The use of land is designed to optimize resources for diverse interest-groups, thus causing pressures to be exerted on the land in varied degrees. Because land-uses are neither influenced by capabilities of existing resources nor based on effective land-use policy, the economic development of land is not conducive to conservation of the environment. Indeed, the attempt to maximize the use of resources constitutes a serious impediment to future development, as most lands are either destroyed or rendered marginal for primary production.However, the best use to which land can be put is ultimately largely a political matter, and this is influenced by socio-economic factors at work in a given environment. Unfortunately, when the use of land is not in harmony with ecological approaches to development, the soils commonly depreciate to counter-productive levels. This is why, when land uses are in opposition, they pose serious questions regarding the extent to which they can adequately sustain life. There is plenty of evidence that the rate of forest depletion in the country may increase in relation to population increase, which is why, without adequate measures being taken, constraints in land-use could lead to shortened fallow periods, reduced crop-yields, overgrazing, indiscriminate burning of vegetation, excessive hunting, poor techniques of mineral exploitation, and application of unconserving agro-technical practices for food production.In the face of the above problems, however, adoption of alley cropping by smallholder farmers, establishment of woodlots for fuel-wood production in the vicinity of large towns, planting of timber trees in the periphery of cocoa and oil palm plantations, private-sector participation in reafforestation, and rehabilitation of mined areas with suitable vegetational forms, are some of the strategies that can reduce the rate of forest depletion in the country.
Hydrology and Soil Fertility of Degraded Grasslands at Cherrapunji in Northeastern India
Authors: Ram Subhash C. , Ramakrishnan P.S. 
Published: August 2009

Four grassland types at Cherrapunji, in northeastern India, namely the Osbeckia, Arundinella, Ischaemum, and Eragrostiella, types, were studied for soil nutrient losses through their hydrology and related soil-fertility changes. Losses through water and the consequent soil-fertility depletion were shown to be related to the frequency of the burn to which these grasslands are subjected. The Ischaemum type, with regular burning at 2-years' intervals, was the most adversely affected, compared with the Osbeckia type, which had not been burnt for the past 6 years.In all the grassland types which were studied, the losses through water were high during the early part of the monsoon period, owing to the poor vegetation cover at that time. A desertified site with the Eragrostiella type of grassland had the lowest soil-fertility level, and had losses through removal in water that far exceeded the prevailing soil-nutrient level.Fire can help in stabilizing the seral grassland vegetation if the soil is sufficiently deep and the frequency of the burn is not too great. On the other hand, too frequent perturbations by fire are apt to result in a desertified landscape that is difficult to restore.
The Role of Government Subsidies in the Population Decline of Some Unique Wildlife Species on Amami Oshima, Japan
Authors: Sugimura Ken 
Published: August 2009

Amami Oshima (Island of Amami) in Japan has five species and two supspecies of animal wildlife that are designated as natural monuments by the national government. However, government subsidy has indirectly induced population decline of some of them through habitat destruction. Self-supporting industries make up only a small portion of the whole economy of Amami Oshima, so that financial support from the national and prefectural governments has been necessary to create a large number of jobs for local people.Forestry has been subsidized by the central governments to a large degree. As a result of cost-reduction in logging through the subsidy which has been devoted mostly to construction of logging roads, most original forests have been replaced by young secondary forests and logged areas in the central part of Amami Oshima, where all the wildlife taxa under consideration are to be observed at present. The governments have planned to manage these young forests with a 35–40 years' rotation-cycle for pulpwood, of which the commercial value is relatively low.Of the involved seven species and subspecies, the Great White's Thrush (Turdus dauma amami), Owston White-backed Woodpecker (Drendrocopos leucotos owstoni), and the Long-haired Rat (Rattus legata), appeared to be so dependent on mature forest (uncut for at least 40 years after selective felling) that they will probably not be able to maintain their populations if all the old forests are cut down. Small populations of the Ryukyu Robin (Erithacus komadori) may be able to survive in young secondary forests, but population decline will be substantial through the decrease in the area of mature forest. On the other three species—the Amami Rabbit (Pentalagus furnessi), Purple Jay (Garrulus lidthi), and Spinous Rat (Tokudaia osimensis)—the effects of clear-cutting of the mature forests are less obvious. Further decreases in the area of mature forests will probably cause a significant reduction in the present population-level of the Amami Rabbit, but negative effects of logging on the other two species should not be very serious. An increase in the length of rotation-cycles, and changes in the use of the subsidy, are proposed for improving the wildlife habitat and the economic efficiency of local forestry.