bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of soil degradation in the Canary Islands (Spain)
Authors: Rodr Rodríguez A. Íguez , Gonz Soto M. C. ález , Hern Hernndez L. A. ández , Jim Mendoza C. C. énez , Ortega González M. J. , Padr Padrón P. A. óN , Torres Cabrera J. M. , Vargas Chávez G. E. 
Published: February 2007

AbstractIn the Canary Islands a number of factors, both natural and induced by human activity, act on the fragile ecosystems and agricultural land to cause increasing problems with desertification and progressive degradation of soil productivity. the results of an assessment of soil degradation in the Canary Islands, The processes, causes and impacts, are presented in this paper. Although several processes and factors contribute to soil degradation in the Canary Islands, two have been found to exert a greater qualitative influence: (a) accelerated erosion (water and aeolian); (b) salinization‐sodification (natural and induced by agricultural use).Approximately 40 per cent of the Canary Islands' land is undergoing rapid erosion. the factors involved May, be grouped into: natural erosion—torrential rainfall, sparse vegetation, high soil erodibility, rugged relief; and erosion due to human activities—unsuitable management of arable soils on the steep slopes, overgrazing and deforestation. About 60 per cent of the surface of the archipelago, including areas given over to intensive agriculture, is affected by salinization.The main factors responsible are: natural—an arid climate and a regime of oceanic winds; and human activities—overexploitation of the aquifers, irrigation with water having a high salt and/or sodium content, intensive monoculture, and excessive and indiscriminate use of chemical fertilizers and other agrochemicals.
Human use of the sand dune ecosystem in the semiarid zone of the Rajasthan Desert, India
Authors: Kumar M. , Bhandari M. M. 
Published: February 2007

AbstractSand dunes form one of the most fragile terrestrial ecosystems. in Rajasthan they have a diverse vegetation and are often utilized by considerable human and livestock populations. a thorough knowledge of the resource utilization by the human and animal populations is essential if the future potential of the ecosystem and its physical stability under changing environmental conditions are to be accurately assessed. This study examines the socio‐economic aspect of land degradation at four sites in Churu and Jhunjhunu districts, northwest Rajasthan. an attempt is made to assess the socioeconomic factors leading to land degradation. Data on human use of the Rajasthan (Thar) Desert semiarid ecosystem were collected through individual interviews, group discussions and field measurements. the present exploitation of soil and vegetation resources, possible future biomass deficiency, its impact on sustainable development and role in land degradation are examined.The average number of people in each household in the study area, and the number of livestock each household maintains are too high to allow a satisfactory income to be sustained. the annual income of 50‐90 per cent of households was less than 10 000 rupees ($US 1 = 17 rupees in 1987). Sale and consumption of milk, wool, surplus animals and wood provide livelihood, supplemented with income from wage labour. Rain‐fed marginal land cultivation produces poor yields and the per capita production is too low to justify the huge soil erosion losses occurring. the number of goats, sheep and cattle owned by the inhabitants has increased tremendously in recent years. Stocking rates vary from 1.63 to 12.08 animals per hectare. the grazing pressure during the dry season, when forage availability decreases, reaches 34.9 animals per hectare. as a result of overgrazing, The land productivity has decreased considerably. the annual fodder deficit values in the study area are enormous. Demand for fuelwood at all the study sites is increasing, yet available forests have already largely been cut down. the distance travelled to collect fuelwood has been increasing, whereas the amount and quality of fuelwood is decreasing. Use of cattle dung to supplement fuelwood during the summer dry season and in drought periods has been decreasing due to low fodder availability and high livestock mortality. Human numbers are increasing, and livestock numbers are also multiplying (except in drought periods) and consequently the available resources are decreasing. Soil erosion and desertification will continue to increase during the next decade unless effective counter measures are undertaken.
Enhancement of revegetation on construction fill by fertilizer and topsoil application: Effect on mycorrhizal infection
Authors: Claassen V. P. , Zasoski R. J. 
Published: February 2007

AbstractThe influence of topsoil and fertilizer application on denuded road construction sites was evaluated to assess its contribution to improvement of vegetation re‐establishment. the study sites were within a mixed hardwood and conifer forest on crushed, unweathered subsurface material with low fertility and low biological activity. Topsoils were removed from the site, stockpiled and reapplied to the site after construction. the effect of topsoil amendment on plant growth, soil fertility, mycorrhizal infection and an index of microbial biomass were measured in field and greenhouse experiments. Plant growth on the topsoil amended field plots were greatly increased relative to treatments with fertilizer but no topsoil. Three years after establishment, dry weight production on the plots without topsoil treatment was about 40 per cent of the plots treated with topsoil. Greenhouse experiments were designed to compare fresh, dried and stockpiled topsoil. These experiments indicated that storage of the harvested topsoil for five months in a stockpile had minor effects on plant growth, soil fertility, mycorrhizal infection and microbial biomass. Topsoil volumes had to exceed 20 per cent of the total soil volume to achieve statistically significant benefits and higher ratios showed greater benefit. the percentage of mycorrhizal infection was greatest in topsoil treatments without fertilizer. the addition of fertilizer increased growth but reduced the percentage of roots forming mycorrhizae. When the total weight of infected roots was calculated, however, infection was found to be greatest with a moderate level of fertilizer (equivalent to approximately 27 kg N ha−1 and 39 kg P ha−1), and was less in both higher fertilizer treatments and in unfertilized treatments. Topsoil amendment increased microbial biomass nitrogen but fertilizer treatment did not.
Evaluation of Eucalyptus Camaldulensis (river GUM) and Chamaecytisus Proliferu (Tagasaste) for salinity control by agroforestry
Authors: Eastham J. , Scott P. R. , Steckis R. A. 
Published: February 2007

AbstractComponents of the soil water balance were measured over a three year period for Eucalyptus camaldulenis and Chamaecytisus proliferus, species commonly used for revegetation in Western Australia, and compared with water balance components for pasture. Marked seasonal trends in evapotranspiration were observed for all species with maxima occurring in the wet months, and minima occurring in summer when rainfall was low and evaporative demand high. in each year of study, annual evapotranspiration and soil water depletions were greater for both tree species than for the pasture, due to the greater extraction of soil water at depth. Upward movement of water from the saturated zone was also found to be greater beneath the deeper rooted perennials than beneath pasture.
Establishment of trees on mixtures of pulverized fuel ash and Gypsum. Part II: Nutrition and trace elements
Authors: Shaw P. J. A. , Moffat A. J. 
Published: February 2007

AbstractNutrients and trace elements were determined in the foliage of nine tree species grown in mixtures of pulverized fuel ash (PFA) and gypsum. No serious macronutrient deficiencies were observed. Treatments with PFA consistently increased foliar levels of boron, potassium and molybdenum, and the poor performance of some tree species in pure PFA was attributed to boron toxicity. Gypsum hindered the uptake of boron when mixed with PFA, however, and co‐disposal of the two wastes could be used to minimize problems associated with boron toxicity.
Losing ground? soil loss and erosion in the highlands of papua new guinea
Authors: Sillitoe P. 
Published: February 2007

AbstractFirst impressions suggest that the risk of soil loss through fluvial erosion from land under cultivation is considerable in the Southern Highlands Province of Papua New Guinea. the climate is very wet all year round, The terrain precipitous, and people regularly farm on steep slopes. the Wola‐speaking people, who occupy a series of valleys in the centre of the province, and who practice a semi‐shifting form of cultivation, are nonetheless off‐hand about soil conservation and declare that erosion is not a serious problem. This paper assesses the status of their assertions by calculating potential soil loss rates. It applies the universal soil loss equation to data on rainfall erosivity, soil erodibility, slope length and steepness, vegetation cover and conservation measures, to compute likely runoff losses. the calculations suggest that, The steep slopes cultivated and wet climate notwithstanding, The local population's assessment of the dangers of erosion is realistic and not reckless. Although rainfall is high, it is rarely of an intensity sufficient to threaten serious soil erosion losses. the physical properties of the soils, which feature volcanic ash components and high organic matter levels, are such that they are particularly resistant to erosion. the staple crop of the region, sweet potato (Ipomoea batatas), also gives particularly good ground cover and protection when established, effectively shielding the soil from erosive rainfall.
Ecological sustainability and the use of chemicals: Is ecotoxicological risk assessment doing its job properly? An introduction to chemical time bombs
Authors: Hekstra G. P. 
Published: February 2007

AbstractTen million chemical substances are registered scientifically, but only 1 per cent, 100000, are known to be traded internationally, and only a fraction of these are assessed to establish (eco)toxicological risks through international and national authorities. Only a few of the substances are natural or systemic; most are xenobiotic and poorly evaluated with respect to their environmental effects. It is not only the chemical accidents that make newspaper headlines, but the creeping accumulation of pollutants in soils, sediments and groundwater which degrade the environment for future generations. Ecotoxicological risk assessment still neglects this ‘hidden pollution’, as it usually deals only with the bioavailable fractions of chemicals in the environment. the ‘lost’ (residue) fractions, however, can have non‐linear and time‐delayed effects (chemical time bombs).As governments need to protect their natural resources (soils, sediments, groundwaters) against negative impacts from chemicals, an ecosystem approach May, help them to overcome the shortsightedness of current ‘acute’ ecotoxico‐logical risk assessments. the Netherlands' risk philosophy on chemicals in the environment is discussed as an example. the National Environmental Policy Plan‐2 (1994) stresses the chain of events associated with a chemical from the raw material, The side effects of its transport, production, use and disposal, to its final effects in the ecosystem, including the time‐delayed responses of pollution. a revised ecotoxicological assessment policy under the new NEPP will have to take account of such chemical time bombs.
Assessment of pollution of groundwater by atrazine
Authors: Kuhnt G. , Fránzle O. 
Published: February 2007

AbstractAtrazine has been used as a powerful herbicide in maize production for about 30 years, but since it became clear that it threatens the quality of groundwater its use has been forbidden in Germany and elsewhere. Nevertheless the risk to groundwater will remain for a considerable time, and this time will vary depending on the soil type. a classification and mapping procedure for groundwater sensitivity has been developed and the risk of groundwater pollution by atrazine assessed. Specific regions of Germany at high risk have been identified using a computer model and statistical data.
Salinization of groundwater and the mobilization of micropollutants: Effect on the food chain
Authors: Th. Scholten M. C. , Szabolcs I. 
Published: February 2007

AbstractAlthough the development of salinization in European soils and waters is less of a problem than in Asia, Africa and Australia, The impact in Europe is likely to be worse because of the much greater interference with stored pollutants. Three types of salinization are discussed here: salinization caused by faulty irrigation, increased evapotranspiration and rises in sea‐level. the potential activation of the chemical time bombs due to climatic changes and the development of the co‐tolerance of plants to metal pollution and increased salinity is considered.
Pollution of sediments in the lake ladoga catchment area and the gulf of finland: influencing factors and processes
Authors: Ikonnikov V. 
Published: February 2007

AbstractSedimentation in the estuary of the Neva River (Gulf of Finland) has been significantly altered in recent years by the construction of a flood prevention barrier for St Petersburg. Concentrations of toxic organic substances and heavy metals have increased 1‐5‐3‐0 fold. a shift in sediment redox potential has occurred in most of the fine‐grained particles and the concentration of dissolved oxygen in the bottom waters has decreasd to 0‐5‐1‐0 mg 1‐1. the changing environmental conditions and intensive human activities in the area have led to the remobilization of the sedimentary material, threatening the ecosystem with secondary pollution. Not only direct industrial discharges are responsible for the contaminants identified; human activities throughout the catchment area and atmospheric deposition affect the capacity of the ecosystems to absorb pollutants and result in the increased migration of persistent pollutants into the Neva estuary.The functions, factors and processes contributing to the transport and sedimentation of toxic substances in the drainage basin of the Lake Ladoga/Neva River system is discussed. Physical (deforestation, drying of marshes) and chemical factors (industrial pollution, agrochemical use) are reviewed. the role of eutrophication in Lake Ladoga in influencing the migration and bioavailability of toxic substances is discussed with respect to its function as a filter and bioreactor. the temporal and spatial variations in the distribution of suspended and dissolved matter in the lake, which is dependent on its morphometric and hydrological characteristics, change the patterns of transport of toxic substances into the Neva estuary. the ecological status of the Neva estuary is reviewed with particular emphasis on the concentration of pollutants in sediments, redox shifts and dumping and drainage activities. the role of gas production and evolution in the remobilization of lipophilic organic substances is considered to be of major importance in shallow estuaries such as this.
Soil and sediment contamination by persistent organic pollutants in the Moravian and Slovakian parts of the danube catchment area and some Bohemian sites in the elbe catchment area
Authors: Holoubek I. 
Published: February 2007

AbstractPolychlorinated biphenyls, polychlorinated dibenzo‐p‐dioxins and dibenzofurans, HCBs and p, p'‐DDE were determined in soil and sediment samples from selected sites in Czecho‐Slovakia. for the first three groups of chemicals soil pollution in Czecho‐Slovakia is very high. in general, The pollution is higher in the Elbe than in the Danube catchment sediments.
Heavy metal and chlorinated hydrocarbon contamination of selected aquatic sediments from the Berlin area
Authors: Pachur H.‐J. , Ahrens M. , Ricking M. , Röper H.‐P. 
Published: February 2007

AbstractSediments from the Berlin area were analysed for heavy metals and chlorinated hydrocarbons. the sedimentological and hydrogeological aspects of the Holocene sediments are discussed and an adapted sampling device for muds with a high water content is described. the contamination of surface sediments and dated cores is shown back in the 19th century; the hydrological influences on the degree of contamination and potential threats to groundwater and, via remobilisation, to surface waters are considered. It is concluded that the sediments of the Berlin area are highly contaminated.
High levels of chlorinated aromatic compounds in deep rhine sediments with special reference to microbial transformations
Authors: Beurskens J. E. M. , De Wolf J. , Van Heuvel H. Den 
Published: February 2007

AbstractSediment cores were taken from the Ketelmeer, a sedimentation area of the River Rhine located in the central part of the Netherlands. Chlorinated benzenes, biphenyls, dibenzo‐p‐dioxins and furans were determined in all or in a selected number of core samples. Levels of these compounds since the late 1930s were established using radionuclide tracers and area‐specific geological time markers. Unexpectedly high concentrations of chlorinated dioxins and furans were found in layers that were deposited in the 1960s and 1970s. the highly toxic 2,3,7,8‐TCDD reached concentrations up to 400 ng kg−1 in the mid‐1960s. Post‐depositional redistribution of pollutants was verified by analysing deeper layers that were unpolluted at the time of deposition. Downward transport was only found for some di‐ and trichlorobenzenes. Possible transformations in the anaerobic sediment were evaluated by analysing sediment top‐layer samples taken in 1972. Supported by laboratory experiments, it became clear that some polychlorinated biphenyls and chlorobenzenes had been microbially dechlorinated in the anaerobic sediments. Up to 80 per cent of the input in the early 1970s has disappeared. on the other hand, The accumulation of a dechlorination product, 1,3,5‐trichlorobenzene, from hexachlorobenzene transformation was found. This dechlorination product is less hydrophobic and therefore more mobile than the parent compound. This phenomenon is of particular concern with respect to groundwater quality.
Chemical time bombs from landfills: Appraisal and modelling
Authors: Boels D. , Fleming G. 
Published: February 2007

AbstractAbout 240 x 106 tonnes of industrial waste, 104 x 106 tonnes of municipal waste and more than 60 x 106 tonnes of sediment sludge are landfilled (65 per cent), incinerated (24 per cent) and partly recycled in Europe annually. About 60000‐120000 landfill sites, occupying 800‐1700 km2, are recorded in the EEC, of which a limited number are in operation. These sites generate 12.5 x 109 m3 of landfill gas annually, of which about 755 x 106 m3 are presently recovered, and 0‐1‐4‐0 x 106 m3 of heavily polluted leachate, which is dispersed to ground and surface waters. the area with polluted groundwater increases annually by 1‐10 per cent (1200‐12000 km2 of contaminated land). Landfill gas contains carcinogenic and pathogenic components and contributes 2 per cent of the total emission of greenhouse gases; locally it is a potential hazard. Incinerators reduce the solid volume to about 30 per cent of the original but cause the atmospheric deposition of acids and dioxins. Emissions of landfill gas, leachate and atmospheric deposition have been recognized as potential chemical time bombs (CTBs). Models are currently available for the estimation of the time at which the effects of these CTBs will become manifest. It is recommended that an inventory of all landfills should be made to assess the potential hazards in detail, to encourage institutions to initiate the clean‐up of contaminated sites and the aftercare of closed sites, and to set up a co‐operative network within the EEC.
Effects of sewage sludge disposal
Authors: Van Berg J. J. Den 
Published: February 2007

AbstractThe disposal of sewage sludge affects the environment as the sludge May, contain harmful components such as pathogenic organisms, organic compounds, heavy metals and excess phosphorus and nitrogen. Depending on the method of disposal, these effects can be immediate or time‐delayed and non‐linear. the effects of dumped or landfilled sewage sludge can be characterized through its leaching capability, which depends on the treatment before dumping. Treatment May, be simple dewatering or advanced incineration, wet oxidation or immobilization. Leach‐ability is considered here.
Contribution of Czecho‐Slovakia to the chemical time bombs study in the danube catchment area
Authors: Petrovič P. 
Published: February 2007

AbstractAn overview is given of the activities of Czecho‐Slovak institutes within the project ‘Long‐term risks for soils, sediments and groundwater in the Danube catchment area,’ as accepted in 1991 by six riparian countries from the Danube basin. the project is divided into: screening maps; analytical methodology; (bio)monitoring; use of geographical information systems (GIS) for data storage and presentation of results; soil vulnerability studies; modelling of processes; and case studies. Twenty‐six tasks are listed, together with authors and addresses of co‐operating organizations included in the Czecho‐Slovakian project. in the initial stages information was gathered to produce maps of hot‐spots in the Czecho‐Slovakian territory of the Danube catchment area. a list of landfill sites is almost ready; surface water pollution for the Danube itself and for the Hron tributary has been evaluated and some proposals for the presentation of the results have been considered. the methodological part of the project summarizes the analytical methods for the groundwater study. Base levels and standards for the comparison of quality have been completed. At present the Water Research Institute is planning to process the results using ILWIS (Integrated Land and Water Information System), which is distributed by ITC (Enschede, The Netherlands) and VITUKI (Hungary). Some administrative and budgetary aspects of the task are considered and the acute need for closer international cooperation is emphasized.
Technical, policy and legal aspects of chemical time bombs with emphasis on the institutional action required in eastern Europe
Authors: Appelgren B. G. , Burchi S. 
Published: February 2007

AbstractTechnical, economic and institutional conditions are changing rapidly in Eastern Europe. the area has inherited a high level of chemical pollution of soil and water resources, leading to grave risks of chemical time bomb effects. With the current financial and manpower constraints and the general stress on the new economies of the subregion, any substantial environmental improvements reversing past trends will require considerable time, during which chemical pollutants will continue to accumulate in soils and waters. Special emphasis is given to diffuse and accelerated pollution from inappropriate or changed land uses. It is suggested on the basis of recent legislation on transboundary and national chemical pollution in Europe that national policies, priorities and legislation shoud be developed throughout Eastern Europe.