bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitrogen status and transformations in coal mine spoil
Authors: Shah S. S. H. , Flowers T. H. , Pulford I. D. 
Published: February 2007

AbstractA detailed study was undertaken to measure mineral nitrogen status, mineralization rate of carbon and nitrogen, nitrification rate and fixation of added ammonium on 90 samples of coal mine spoils collected throughout Central Scotland. The inorganic nitrogen status of the spoils was very low (mean 3.4 mg N kg−1). The rate of carbon dioxide evolution was high compared to the low rate of nitrogen mineralized, resulting in a mean mineralized C:N ratio of 178. Nitrification of added ammonium was measurable on only half of the samples studied. Spoil with pH < 4.8 showed no nitrification of added ammonium. However, on some sites above this pH no net nitrification was measured, which suggested the absence of nitrifying bacteria. A considerable amount of applied ammonium nitrogen was lost either as a result of ammonium fixation by clay minerals, or assimilation by the heterotrophic population due to the wide mineralizable C:N ratio.
A comparison of soil degradation under smallholder farming and large‐scale irrigation land use in Kano State, Northern Nigeria
Authors: Essiet E. U. 
Published: February 2007

AbstractChanges in soil properties under two land use types: smallholder farms and large‐scale irrigated agriculture were investigated over a period of 13 and 14 years respectively using the following parameters: particle size distribution, soil pH, exchangeable cations, cation exchange capacity, total organic carbon and nitrogen and total and available potassium and phosphorus. Results indicate that more adverse changes took place in soils under large‐scale irrigation than in those under smallholder farms during the periods under consideration. Agricultural sustainability is more likely to be achieved for smallholder farms than for large‐scale irrigation where soil degradation resulting from loss of fine soil particles through erosion can be a serious hindrance to long‐term land use. In order to achieve agricultural sustainability in Kano State, it is recommended that chemical fertilizers be incorporated into the smallholder farming system, while the adoption of suitable soil conservation practices would make the large‐scale irrigation systems more stable and sustainable.
Key factors affecting the initiation and progress of gullying in dambos in parts of Zimbabwe and Malawi
Authors: McFarlane M. J. , Whitlow R. 
Published: February 2007

AbstractAccelerated gullying of dambos (seasonally waterlogged bottomlands) on commercial farms in Zimbabwe has resulted in legislation curtailing dambo cultivation, even in indigenous fanning areas. The transfer of indigenous cultivation to interfluve areas and the resultant concentration of cattle grazing in dambos initiated similar gullying. Facilitated overland flow was perceived to be the cause of gullying both in the case of dambo cultivation and dambo grazing, this overland flow re‐excavating what was believed to be fluviatile infill.Geomorphological evidence is assembled to show that dambos are not ‘fossil’ fluviatile systems, nor is their clay infill alluvial. They are the ‘lows’ of a landsurface irregularly lowered by differential leaching. The infill forms by precipitation of materials leached from the interfluve profiles and discharged into the dambos. The fluviatile‐like configuration of dambos is attributed to integration of sub‐clay groundwater movement, resulting from landsurface incision. Accelerated gullying in Zimbabwe is deduced to be caused by breaching of the dambo clay by subsurface water movement. The particular vulnerability of Zimbabwe dambos is attributed to: (1) the watershed situation; (2) shallow weathering and (3) the thinness of the dambo clay. Evidence from Malawi indicates that interfluve deforestation and cultivation of shallow‐rooted crops conserve water, raising the groundwater level. Such an increased head of groundwater also appears to have occurred in Zimbabwe; this would strengthen upward discharge in the dambos, promoting gullying. Urgent land and water policy revision is required, allowing restoration of dambo cultivation and reafforestation of interfluves, if dambos are to be conserved and the resources which they offer satisfactorily utilized.
The nature and management of saprolite aquifers in the wheatbelt of western Australia
Authors: George Richard J. 
Published: February 2007

AbstractRegional weathered‐zone goundwaters in the southern part of Western Australia are primarily stored in a granular saprolite aquifer derived from the isovolumetric weathering of granitic and gneissic rocks. Recent drilling has confirmed the existence of permeable materials capable of yielding groundwater of a suitable quality for livestock. Development of supplies of 10 to 250 kl d−1is realisic and would complement local livestock, domestic and Government water supply systems. Wheatbelt aquifers currently supply 18 to 25 per cent of all water used for livestock in the agricultural areas of the southern part of Western Australia, although less than 1 per cent of the available resource is being utilized. Unused groundwater, artificially recharged by water‐use inefficiencies of agricultural development, provides both a potential resource and a cause of soil and water quality deterioration.Groundwater pumping may provide one method of aquifer control to mitigate the influence of secondary salinization. Pumping the low transmissivity Wheatbelt aquifers provides a means to lower water‐tables and limit the volume of groundwater reaching saline discharge areas at low points in the landscape. Unlike aquifer pumping systems developed in saline discharge areas, extraction systems in groundwater recharge areas, or in saline areas where groundwaters are of a suitable quality for agricultural use, can be used to mitigate salinity. The volume of groundwater available in southwestern Western Australia usually exceeds livestock requirements, to maintain low water‐tables, the water has either to be pumped to suitable drainage systems or alternative uses must be sought.
False expectations of labour participation in the construction of permeable infiltration dams in burkina faso
Authors: Vlaar J. C. J. , Brasser M. B. 
Published: February 2007

AbstractStudy of the labour participation in constructing permeable infiltration dams for soil and water conservation to increase agricultural production in the Province of Bam, Burkina Faso, revealed a progressive decline in cooperation at the village level, despite the high profitability of the completed structures*. This decline was mainly because not all the participating people could obtain such a dam for themselves due to constraints in rights to land and limited possibilities for an individual to mobilize labour. Development agencies can stimulate better labour participation by organizing cooperation on a smaller scale (i.e. village section or ‘quartier’, instead of village) or, probably with more success, by putting project means at the disposal of individual farmers, to enable them to mobilize labour for constructing permeable infiltration dams on their own plots.
The degradation of the algerian environment through economic and social ‘development’ in the 1980s
Authors: Zaimeche S. E. , Sutton K. 
Published: February 2007

AbstractConcern for the better management of environmental resources grew during the 1980s. While this concern encompassed the misuse of the Third World's resources, those nations' governments and their peoples showed less awareness of the environmental damage being done in their quest for development. Environmental degradation has reached serious proportions in Algeria where oil wealth has masked failings of agricultural production and, together with industrialization, has provided a ‘veneer’ of economic development.The vulnerability of Algeria's natural environment and the fragility of its ecosystems have been stressed by Cǒte (1983). Once cleared, Algeria's woodlands and forests are slow to re‐establish and surface deposits are easily erodable. Soils were largely formed under past climatic conditions, and so cannot be restored naturally by present pedogenetic processes. Such an environment is difficult and delicate to exploit to any high degree of agricultural intensification and is under increasing demographic pressure. Culturally and organizationally the agricultural system is far from ideal if agriculture is to be sustained. Often in Algeria the highest rainfall falls on the steeper slopes while the gentler slopes receive insufficient for agriculture. Only 500 000 hectares out of Northern Algeria's 38–40 million hectares receive more than 600 mm of rainfall and have slopes of less than three per cent (Cǒte, 1983). As much as 20 million hectares of Northern Algeria were identified by Dregne (1983) as … ‘vulnerable to desertification’ with large areas falling into his ‘severe’ risk category.This study seeks to demonstrate the dimensions of environmental degradation through observations and the monitoring (during the 1980s) of Algeria's media: largely newspaper and television reports. Particular emphasis is placed on the growing environmental ‘crisis’ since 1988. It should be stressed that the Algerian Government uses a controlled media to disseminate official information. Misuse and overuse of environmental resources have combined with inadequate government economic policies and a neglect of ecological issues to cause the ‘crisis’.
Adoption of soil conservation practices: An empirical analysis in Ontario, Canada
Authors: Smit B. , Smithers J. 
Published: February 2007

AbstractSoil degradation threatens environmental quality and sustainable food production. As a result of efforts to promote soil conservation, farmers in Canada are thought to be reasonably aware of both the importance of conservation and the existence of remedial and preventive practices. Despite this, the adoption of conservation practices has been less than overwhelming. Forces other than awareness and positive attitude seem to be constraining many land managers from employing available conservation methods. This paper presents the findings from an empirical investigation of the use of soil conservation practices and barriers to their adoption in the southwestern region of Ontario, Canada. The analysis is set in the context of literature on technology adoption. A scheme for measuring farm‐level conservation effort is developed, and barriers to adoption are derived from an analysis of a range of independent physical, personal, and economic factors, and from the obstacles or constraints identified by producers themselves. Key barriers relate to economic pressures, the complexity and compatibility of practices, and perceptions regarding the actual need for practices. The findings have relevance for the design of public policies and programs, notably the importance of supplying information on farm‐level implications of conservation methods and the need for a stable economic environment for agriculture to allow longer‐term planning.
Erosion control practices applied to granitic roadfills for forest roads in Idaho: Cost effectiveness evaluation
Authors: Megahan W. F. , Monsen S. B. , Wilson M. D. , Lozano N. , Haber D. F. , Booth G. D. 
Published: February 2007

AbstractCost effectiveness of six alternative road embankment construction practices and 16 alternative fill‐slope stabilization practices was evaluated as means for controlling erosion on forest roads built on granitic soils in Idaho (USA). A total of 63 bordered erosion plots 1‐8 m wide by 4‐6 m long, were used. Eroded material was collected in troughs at the bottom of each plot in the spring and fall. Measurements began in the fall of 1981 and continued until the fall of 1983. Costs were obtained by tabulating actual labor, equipment, and supplies used to install the treatments. Rainfall erosivity values accumulated for the snow‐free periods between erosion measurements proved to be a statistically significant covariate for the analysis of treatment effects. There were no significant differences between the three embankment construction practices (sidecast, layer placed, and controlled compaction). But surface rolling did significantly increase erosion in all cases. Nine of the post‐construction soil stabilization measures significantly reduced erosion, and one measure significantly increased erosion (P < 0‐5). Stabilization measures that combined mulches with revegetation appeared to be more beneficial for erosion control than either mulches or revegetation alone. Rankings of the erosion control effectiveness of individual soil stabilization practices were different from the rankings of the cost effectiveness of the practices. Application of alternative treatments is discussed.
Should all degraded landscapes be restored? a look at the appalachian copper basin
Authors: Quinn M.‐L. 
Published: February 2007

AbstractRehabilitation of degraded landscapes is generally regarded as the most appropriate objective. Occasionally, however, other aspects of the situation need to be considered and may lead to a different decision. This paper presents the case of the Appalachian Copper Basin, located mainly in south‐eastern Tennessee, USA, which was degraded years ago as a result of copper mining and smelting. A brief history of the site is given, along with a review of some rehabilitative efforts. Discussion then turns to the way visitors and residents perceive this landscape, the impact these two viewpoints have had over the years, and how they have (or have not) changed. Landscape values are also examined, the interpretation of which largely determines a person's opinion toward rehabilitation. The point is made that some degraded landscapes can have value as degraded landscapes, in this instance now primarily historical and cultural. The current situation in the Copper Basin is summarized and an alternative course of action suggested. It is concluded that rehabilitation is not always the only, or even the most important, goal and that degraded landscapes of long standing sometimes require special consideration.
Amelioration of a highly degraded tropical alfisol by planting I. Changes in soil physical and chemical properties 1989‐91
Authors: Hulugalle N. R. 
Published: February 2007

AbstractThis paper examines soil amelioration by planting 15 leguminous and graminaceous plant species, including herbaceous annuals, perennials and biennials, and woody perennials and biennials. Disturbed and undisturbed natural regrowth were planted with leguminous species, in some cases with fertilizer applied at planting (400 kg ha−1of 15:15:15 NPK). The studies were made on two highly degraded sites in southwestern Nigeria which had been subjected to intensive mechanized cropping for a period of 10 years. Changes in soil physical and chemical properties were monitored from 1989 to 1991.Acacia difficilis, Brachiaria lataandMucuna utilishad the lowest survival rates by the following growing season. Soil fertility and compaction levels differed between sites. Planting had no effect on the latter. The decreases in compaction (i.e. macroporosity) between 0.00 and 0.10 m depth at both sites one month before and five and 17 months after planting were 43, 59 and 61 per cent, respectively were attributed to exclusion of heavy machinery from the sites. Large decreases in fertility occurred at both sites and were attributed to a combination of nutrient extraction and to leaching. Between fallow species, exchangeable Ca, pH and the cation‐exchange capacity (CEC) were greater and total acids lower for herbaceous cover compared with woody perennials, and was attributed to a higher Ca demand by the latter. Highest and lowest values of Ca, CEC and pH occurred in plots where plant material was returned to the soil (i.e. by cutting or die‐back) and in cropped plots, respectively. Natural regrowth was as effective or better than planted species in improving soil physical and chemical properties. Therefore the use of exotic plant species for ameliorating highly degraded alfisols is unnecessary. Amelioration of highly degraded alfisols may be best effected by allowing natural regrowth to occur while excluding all mechanized traffic from the site.
Re‐establishing life in restored topsoils
Authors: Scullion J. 
Published: February 2007

AbstractSurface mining activities and other large civil engineering works often involve the removal, storage and reinstatement of topsoil. Disturbance disrupts normal biological functions within the soil and can markedly change the environment within which soil organisms must exist. This has implications for soil fertility and for the overall ecology of replaced land. A number of studies have investigated the impact of opencast coal mining practices on soil organisms and their capacity for recovery following site reinstatement. The extent and duration of any adverse effect varies from one group of organisms to another according to their vulnerability to damage, their capacity for recovery and their ability to recolonize areas from which they have been eliminated. Three groups of organisms—earthworms, aerobic bactería and vesicular arbuscular endophytes—are considered, to illustrate their differing responses to soil disturbance and the various factors limiting their early recovery throughout a restored area. Given favourable management, consistent with good general rehabilitative practice, the re‐establishment of normal earthworm populations depends entirely on the distribution of an inoculum. For aerobic bacteria adverse physical conditions in reinstated soils are the overriding influence determining levels of activity. For mycorrhizal fungi both soil conditions and the absence of an inoculum may delay recovery, although the evidence in support of this view is inconclusive.
Degradation of ‘reclaimed’ lands previously disturbed by coal mining in Wales: Causes and remedies
Authors: Haigh M. J. 
Published: February 2007

AbstractLarge tracts of land, officially described as ‘reclaimed’ from former mineral workings, are in poor condition. Problems include gullying, soil erosion, soil compaction, accelerated run‐off and poor vegetation cover. Some of these problems are caused by low quality and inappropriate engineering. Some are due to poor land husbandry. There is a need for a national system of quality control inspection for land reclamation sites and provision for training in the special problems of managing reclaimed lands. However, many further problems result from natural soil‐forming processes, notably the accelerated breakdown of newly exposed minestones. This chokes the soils with fine particles, decreasing permeability and increasing bulk density. Current research directed to correcting this problem uses trees to build new self‐sustaining soils from the ground up and to promote the development of a large and active community of soil organisms. It is hoped that the polysaccharide secretions of these organisms will bind the newly created clays into stable soil aggregates.
Development of pollution‐neutralizing properties in very young mine soils
Authors: Gil‐Sotres F. , Leirós M. C. , Trasar‐Cepeda M. C. 
Published: February 2007

AbstractVarious properties capable of neutralizing environmental pollution (aggregate stability, buffer capacity and ion adsorption capacity) were determined in spoil from a lignite mine in Galicia (northwest Spain) and in mine soils of four and seven years age developed from this spoil. Buffer capacity and the adsorption of copper, cadmium and phosphate increased markedly with soil age, whereas the dispersion ratios of both macro‐ and micro‐aggregates decreased sharply. These changes are attributed to the known increase in organic matter and extractable iron and aluminium. These components aid interparticle binding and create both exchange sites and specific adsorption sites. The ultimate causes are thought to be the successful establishment of an active field plant cover, the considerable colloid content of the parent material, the management of the mine soils and the climatic conditions of the area, which favour both the accumulation of soil organic matter and the weathering of the parent material.
Terracing and accelerated soil loss on rwandian steeplands: A preliminary investigation of the implications of human activities affecting soil movement
Authors: Lewis L. A. 
Published: February 2007

AbstractThroughout Rwanda, terracing was reintroduced in 1973 as the major conservation practice to minimize soil loss on its steep agricultural lands.1 Terracing has been partially successful in reducing soil losses resulting from nonchannelized runoff, the goal of this practice. However, because of the widespread fragile environmental conditions in the highlands, soil fertility has decreased and soil acidity increased in numerous fields as a direct result of the terracing. To maintain sufficient agricultural yields, within the constraints of a low resource agricultural system, farmers have responded to the acidity and soil fertility problems by systematically removing a portion of the terrace berm during field preparation. This practice, in response to the changing environmental situation due to terracing, results in significant amounts of soil displaced downslope year after year. This human‐induced soil erosion process seriously counters many of the intended benefits of terrace construction and is contributing to the land degradation problem. The results of this study emphasize the need for both conservation strategies and the measurement of soil loss to be sensitive to human‐induced as well as natural erosional processes. By not considering the human response to terrace construction, the benefits of this conservation practice have been seriously offset.
Afforestation as an interim measure to improve reclaimed lands in singapore
Authors: Lee S. K. , Goh K. C. , Yee S. O. 
Published: February 2007

AbstractLand reclamation using clay and sand materials has been used to increase land area in Singapore. Although some of these areas are put to immediate use, others are ear‐marked for future development. in the latter instances, in the interim period, afforestation measures involving some treatment of the land have been adopted. This paper discusses the process of afforestation at two sites with different but poor soils and the performance of the different species of trees planted (which are now 12 years old). the benefits of such an afforestation exercise are convincing and a similar but less expensive process could be adopted to afforest reclaimed lands or rehabilitate derelict lands in developing countries to provide wood for fuel or other purposes.