Modifications in phosphorus loading to Onondaga Lake,U.S.A., Associated with alkali Manufacturing

The effects of an alkali production facility on P loading to the epilimnion of Onondaga Lake are documented for the spring to fall interval of 1980 and 1981. The effects include additional load to the epilimnion from the hypolimnion and the outlet, and reduced loads from dense, ion-enriched inflows. Despite the compensating effects, the load received by the epilimnion from spring through fall is greater than previously estimated as a result of the manufacturing operations.     

The density of inflows to Onondaga Lake,U.S.A., 1980 and 1981

The temporal distributions of the densities of inflows to Onondaga Lake were calculated for the spring to fall period of 1980 and 1981, and compared to the attendant density stratification in ion enriched Onondaga Lake. The industrial utilization of the lake resulted in substantial density differences between the inflows and the lake. Inflows carrying substantial fractions of industrial ionic waste were more dense than the lake, and at times plunged to stratified layers. Water withdrawn from the lower layers of the lake for industrial cooling was displaced to the upper layers as a result of heating. Dilute fluvial inflows were substantially less dense than the lake. The density differences between the inflows and the lake were largely responsible for the rather unique features of density stratification documented for the lake in 1980, and are probably of further importance in nutrient loading to, and cycling in, Onondaga Lake.     

Elemental composition and speciation of some landfill leachates with particular reference to cadmium

The elemental composition and speciation of four southern Ontario municipal solid waste landfill leachates were investigated. Leachate samples were analyzed for major cations and anions, together with the trace heavy metals Cd, Cu, Fe, Mn, Ni, Ph, and Zn. The leachates were found to contain high concentrations of alkali and alkaline earth metals and also of chloride ions. Cadmium concentrations in all of the leachate samples exceeded maximum acceptable levels for potable water. The computer model SOILCHEM was used to calculate the speciation of elements in the landfill leachates. Alkali and alkaline earth metals were predicted to exist primarily as uncomplexed metals. The heavy metals were predicted to exist as either free metals or as complexes with chloride, fulvic acid, hydroxide or sulphate. The speciation of Cd as a function of pH was investigated further for each of the leachates. Humic acid and chloride complexes dominated the aqueous chemistry of leachate Cd.     

The distribution of nitrogen species in polluted Onondaga Lake,N.Y., U.S.A.

The temporal and vertical distributions of four N species, N0₃ ^?, NO₂ ^?, total ammonia (T-NH₃), and free ammonia (NH₃), are documented for Onondaga Lake, an urban, polluted, hypereutrophic, dimictic, lake that receives a very high load of T-NH₃. Nitrate and NO₂ ^? were lost rapidly from the hypolimnion, and T-NH₃ accumulated to high concentrations (maximum > 10 mgN L^?1), after the onset of anoxia, consistent with the lake's high level of productivity. The concentrations of T-NH₃, NH₃ and N0₃ ^? that were maintained in the epilimnion (average concentrations at a depth of 1 m of 2.81, 0.16 and 0.91 mgN L^?1, respectively), and concentrations of N0₂ ^? that developed in the epilimnion (maximum of 0.48 mgN L^?1), were high in comparison to levels reported in the literature. These elevated concentrations are largely a result of the extremely high loads of T-NH₃, and its precursors, received by the lake. Water quality problems in the lake related to the prevailing high concentrations of N species include potential toxicity effects and severe lake-wide oxygen depletion during fall turnover.     

Economics of p fertilization of two soybean varieties at Jabalpur,M.P., India

Abstract

An economic interpretation was applied to a soybean yield prediction equation derived from data obtained in an experiment at Jabalpur, M.F. It was shown that no level of applied P could substitute for variety selection in terms of either soybean yield or economic returns per ha. Illustrative examples of the minimum price that must be obtained for soybeans before it is profitable to use P fertilizer for given price situations were shown.     

The extractive potential of peats in mid-wales with particular reference to the county of powys

The county of Powys is rich is peat with the most extensive deposits situated in the uplands of the north and west. The historical importance of peat-cutting in the rural economy is examined. Most peatlands are now drained or used for rough grazing, forestry and nature conservation. These practices, coupled with the slow growth rate of peat and its widespread erosion, render peat-cutting a non-viable alteranative energy source, except for the most remote farmsteads.     

Chloride in the pore water and water column of Onondaga Lake,N.Y., U.S.A.

The vertical distributions of Cl in the pore waters of the sediments and in the water column of Onondaga Lake, New York, are documented and used to estimate the diffusion flux of Cl across the sediment-water interface, and establish the reduction in lake concentrations that has occurred as a result of the closure of an industrial source of Cl. Despite the industrial enrichment of the water column with Cl over the last 100 yr, gradients within the upper sediments toward the overlying water of 6.9 to 8.5 × 10^?2 mg cm^?3 cm^?1 exist in the deep basins of the lake. These upwards gradients are apparently a manifestation of the salt deposits that underlie the region. The estimated diffusion flux from the sediments to the water column, 3.2 × 106 kg yr^?1, represents a small percentage of the external load during the operation of the industry (0.4%) and after its closure (1.6%). The Cl concentration has decreased approximately 70% in response to an approximately equal percent reduction in external loading, as a result of closure of the industry. This supports the position that the lake's concentrations largely reflect external loading and lake flushing associated with surface inputs.     

A review of some problems of tropical marine conservation with particular reference to the Tanzanian coast

The productivity, diversity and susceptibility to stress of tropical marine communities are compared with those of temperate marine communities. The question of the i importance of conservation is raised.The applicability of island biogeographical theories in relation to the design of marine reserves is briefly reviewed. It is suggested that the contention that conservation areas should always consist of the largest possible single area is not necessarily correct for the tropical marine environment.Conservation problems of particular habitats within Tanzanian coastal waters are detailed with special reference to the following: coral reefs, rocky intertidal platforms, cliffs, sandy beaches, sandy-muddy tidal flats, seagrass beds, mangroves, estuaries and small islands. The plight of some endangered species is discussed.Conclusions are drawn regarding the present status of marine conservation in Tanzania.     

Soil acidification and the importance of liming agricultural soils with particular reference to the United Kingdom

Soil acidification is caused by a number of factors including acidic precipitation and the deposition from the atmosphere of acidifying gases or particles, such as sulphur dioxide, ammonia and nitric acid. The most important causes of soil acidification on agricultural land, however, are the application of ammonium‐based fertilizers and urea, elemental S fertilizer and the growth of legumes. Acidification causes the loss of base cations, an increase in aluminium saturation and a decline in crop yields; severe acidification can cause nonreversible clay mineral dissolution and a reduction in cation exchange capacity, accompanied by structural deterioration. Soil acidity is ameliorated by applying lime or other acid‐neutralizing materials. ‘Liming’ also reduces N₂O emissions, but this is more than offset by CO₂ emissions from the lime as it neutralizes acidity. Because crop plants vary in their tolerance to acidity and plant nutrients have different optimal pH ranges, target soil pH values in the UK are set at 6.5 (5.8 in peaty soils) for cropped land and 6.0 (5.3 in peaty soils) for grassland. Agricultural lime products can be sold as ‘EC Fertiliser Liming Materials’ but, although vital for soil quality and agricultural production, liming tends to be strongly influenced by the economics of farming. Consequently, much less lime is being applied in the UK than required, and many arable and grassland soils are below optimum pH.     

Diversity of wood-apple (Limonia acidissima L., Rutaceae) genetic resources in South India

Genetic Resources and Crop Evolution - Wood-apple (Limonia acidissima L.) is an undomesticated nutritionally and medicinally potential monotypic tree species of the genus Limonia, which belongs to...     

Reclamation problems for the area of a former borehole sulphur mine with particular reference to soil air properties

In order to select appropriate methods of reclamation of anthropogenic soil in the area of the former ‘Jeziórko’ borehole mine, the air capacity and air permeability of the soil were measured. A field covering an area of 6·25 ha in which the former mining boreholes were only eliminated and no other reclamation treatments carried out was chosen for the study. The control stand was located in phytocoenosis Querco‐Fagetea situated in the vicinity of the sulphur mine, but outside the area of direct mining activities on Haplic Gleysol. Samples were collected from 0–10, 10–20 and 20–30 cm layers in 25 equally distributed locations of anthropogenic soil and 1 of natural soil. The soil water‐air properties at the soil water potential of −9·81 kPa and at the potential at the time of soil collection (the so‐called actual state) were determined. Spatial relations in the capacity and air permeability observation series were assessed for post‐industrial soil by geostatistical methods. Kriging with a linear variogram was used. Geostatistical analysis made mapping of the air properties of heterogenic soil cover in the study area possible. Non‐reclaimed soils of the experimental field were characterized by faulty aeration resulting from a relatively low air capacity and, additionally, insufficient air permeability. The important objective of reclamation should be the homogenisation of the reconstructed soil in order to achieve equally good soil structure and air conditions favourable for vegetation within the whole investigated area. Copyright © 2009 John Wiley & Sons, Ltd.     

Responses of Nutrients to Experimental Acidification and Recovery in Little Rock Lake,U.S.A.

Nutrient concentrations and cycling processes were studied in Little Rock Lake, Wisconsin, U.S.A., during experimental acidification from pH 6.1 to target pH values of 5.6, 5.1 and 4.7 and during the first four years of recovery. Surface waterconcentrations of ammonium, nitrate, soluble reactive phosphate,and total phosphate were not affected, but total nitrogen was lower from year 2 at pH 5.6 until the end of recovery year 3 (pH 5.3). The decrease was attributed to lower dissolved organicN. Annual maximum concentrations of N and P forms at 9 m depth in the hypolimnion increased with decreasing pH, but most of theincrease resulted from a drought-induced decline in lake levelduring acidification that brought the 9 m sampling location closer to the sediment. In contrast to findings elsewhere, acidification of Little Rock Lake had no effect on rates of nitrification during winter ice-cover. Dissolved silica concentrations increased slightly at pH 4.7, probably because of a pH-induced decrease in the diatom population, but hydrologicfactors were more important in controlling silica levels than waspH. Most of the predictive hypotheses made about the effects ofacidification on nutrient forms and processes or their recoveryin the lake were qualitatively correct.     

Land birds of Tuamotu Archipelago, Polynesia: relative abundance and changes during the 20th century with particular reference to the critically endangered Polynesian ground-dove (Gallicolumba erythroptera)

We report relative abundances and distributions of land bird communities on eight isolated islands of the Tuamotu Archipelago (Polynesia, South Pacific Ocean) during two 21-day expeditions in 1999. The selection of islands was based on the historical range of the Polynesian ground-dove (Gallicolumba erythroptera), in the hope of finding populations of this critically endangered species. Data were also collected on the Tuamotu sandpiper Prosobonia cancellata, the Atoll Fruit-dove Ptilinopus coralensis, the Tuamotu reed-warbler Acrocephalus atyphus, the Spotless Crake Porzana tabuensis and the Bristle-thighed Curlew Numenius tahitiensis, and on introduced predators (cats, rats, pigs and dogs). None of the five land-bird species recorded previously, in 1922 and 1974, has completely disappeared, but ranges of several species have contracted. Only one population of G. erythroptera erythroptera was found and it is the only population known for this species today. Our data also raise particular concern for the future of the Tuamotu sandpiper.     

The use of dialysis cells for investigating pore water composition in wetland substrata,with particular reference to dissolved iron and sulphide

Abstract

Details and some evaluation are given of the use of a dialysis method for sampling pore water from depth in wetland substrata (peats), with particular reference to measurement of concentrations of ion species with stabilities dependent on redox potential. The method is based upon the burial and subsequent retrieval (after equilibration) of cells made from dialysis membrane filled with deionized water. Preliminary results of field investigations of concentrations of dissolved iron and sulphide in the pore water of base‐rich mires, as sampled by this method, are given. Results suggest that the method could have very considerable application and that its potential, and possible problems, deserve further examination.     

Response of blue spruce (Picea pungens) to manganese pollution from MMT

The use of methylcyclopentadienyl manganese tricarbonyl (MMT) in unleaded gasoline has become a source of manganese (Mn) contamination to which urban ecosystems are exposed. The potential of coniferous trees as spatial and chronological indicators of Mn pollutation was investigated. Manganese concentrations in xylem from blue spruce (Picea pungens) growing near (high-exposure site) and far (low-exposure site) from a road were measured as a function of the year of wood formation. Exchangeable Mn content, which is the soil fraction most readily available for uptake by trees, was also measured in the soils of both sectors. The results of the soil analysis show that exchangeable Mn concentrations are about 10 times higher in soils exposed to contamination (p<0.0005), in=" comparison=" with=" the=" concentrations=" found=" in=" soils=" weakly=" exposed.=" however,=" the=" mn=" concentrations=" in=" the=" trees=" near=" the=" road=" were=" not=" significantly=" different=" from=" those=" in=" the=" reference=" trees=" (p=">0.05). Therefore, it appears that blue spruce is not sensitive to soil Mn contamination arising from the use of MMT in gasoline.