Controlling factors and environmental implications of mercury contamination in urban and agricultural soils under a long-term influence of a chlor-alkali plant in the North–West Portugal

2008 ◽  
Vol 57 (1) ◽  
pp. 91-98 ◽  
Author(s):  
A. Cachada ◽  
S. M. Rodrigues ◽  
C. Mieiro ◽  
E. Ferreira da Silva ◽  
E. Pereira ◽  
...  
Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.


2008 ◽  
Vol 59 (3) ◽  
pp. 247 ◽  
Author(s):  
David W. Lester ◽  
Colin J. Birch ◽  
Chris W. Dowling

Nitrogen (N) and phosphorus (P) are the 2 most limiting nutrients for grain production within the northern grains region of Australia. The response to fertiliser N and P inputs is influenced partly by the age of cultivation for cropping, following a land use change from native pasture. There are few studies that have assessed the effects of both N and P fertiliser inputs on grain yield and soil fertility in the long term on soils with contrasting ages of cultivation with fertility levels that are running down v. those already at the new equilibrium. Two long-term N × P experiments were established in the northern grains region: one in 1985 on an old (>40 years) cultivation soil on the Darling Downs, Qld; the second in 1996 on relatively new (10 years) cultivation on the north-west plains of NSW. Both experiments consisted of fertiliser N rates from nil to 120 kg N/ha.crop in factorial combination with fertiliser P from nil to 20 kg P/ha.crop. Opportunity cropping is practiced at both sites, with winter and summer cereals and legumes sown. On the old cultivation soil, fertiliser N responses were large and consistent for short-fallow crops, while long fallowing reduced the size and frequency of N response. Short-fallow sorghum in particular has responded up to the highest rate of fertiliser N (120 kg N/ha.crop). Average yield increase with fertiliser N compared with nil for 5 short-fallow sorghum crops was 1440, 2650, and 3010 kg/ha for the 40, 80, and 120 kg N/ha, respectively. Average agronomic efficiency of N for these crops was 36, 33, and 25 kg grain/kg fertiliser N applied. This contrasts with relatively new cultivation soil, where fertiliser N response was generally limited to the first 30 kg N/ha applied during periods of high cropping intensity. Response to P input was consistent for crop species, VAM sensitivity, and starting soil test P level. At both the old and new cultivation sites, generally all winter cereals responded to a 10 kg P/ha application, and more than half of long-fallow sorghum crops from both sites had increased grain yield with P application. At the old cultivation site, average yield gain for 10 kg P/ha.crop treatment was 480 kg/ha for all winter cereal sowings, and 180 kg/ha for long-fallow sorghum. Short-fallow sorghum did not show yield response to P treatment.


1978 ◽  
Vol 29 (4) ◽  
pp. 711 ◽  
Author(s):  
AS Hodgson

Two experiments were conducted to determine the growing degree-day (D°) requirements of annual B. campestris and B. napus cultivars, and to evaluate their use in planning crop development strategies to avoid frost and moisture deficit at three locations. In the first experiment, base temperatures and D° requirements were calculated for four phases from planting to grain-filling, on the basis of linear temperature-development rate responses measured in the field at Tamworth, N.S.W. The phenological pattern of each species was predicted for several planting dates at locations representing the north-west slopes, northern tablelands and an intermediate region, by using long-term mean daily temperatures and calculated Do requirements. From these predictions and long-term mean daily rainfall and pan evaporation rates, the available soil moisture depletion was estimated for each planting date. For each location, planting date strategies for both species were evaluated for avoidance of frost and moisture deficit. The predicted optimum planting dates for B. napus and B. campestris were, respectively, 20 June and 5 August for the north-west slopes, 20 August and 1 October for the northern tablelands, and 30 June and 18 August for the intermediate region. In the second experiment, the influence of planting date on the grain yield of B. campestris and B. napus was studied in several seasons at each of the locations studied in the first experiment. The planting date that gave the highest yield varied between species and locations. B. campestris was favoured by later dates than B. napus. For both species these dates were earliest on the north-west slopes and latest on the northern tablelands. Yields of B. napus were higher than those of B. campestris at all locations when each species was planted at a favourable time. Predicted optimum planting dates from experiment 1 are discussed in relation to the field results from experiment 2. _____________________ *Part I, Aust. J. Agric. Res., 29: 693 (1978).


Author(s):  
A. J. Southward

The inshore fishery for the pilchard in Cornish waters has existed for several hundred years, and such records as are available concerning fluctuation in catches and market conditions have been reviewed by Couch (1865), Cushing (1957) and Culley (1971). Although pilchard have been landed from Lyme Bay, from the eastern half of the Channel, and from the southern North Sea (Couch, 1865; Furnestin, 1945; Cushing, 1957; personal communications G. T. Boalch) the catches have usually been incidental to other fisheries and more sporadic than in Cornish waters. Traditionally there are three areas fished for the Cornish pilchard: on the north-west coast around St Ives; in Mounts Bay and towards the Scillies; and between the Lizard Pt and Bolt Tail in Devon (Couch, 1865; Culley, 1971). The latter region, constituting the inshore waters of south-east Cornwall and south Devon, effectively forms the eastern limits of the regular occurrence of commercial shoals. Knowledge of the breeding and life-history of the fish in this region has always been scarce and subject to much hearsay evidence (reviewed in Southward, 1963). Up to quite recently it was thought that the main spawning area lay well to the west of the entrance to the Channel, and it was not until the investigations reported by Corbin (1947,195°) a nd Cushing (1957)tnat it was conclusively shown that extensive spawning can occur within the English Channel from May to October. The relationship of the spawning in the western Channel to the other areas of spawning off the entrance to the Channel and in the northern Bay of Biscay is illustrated in a recent series of reports (Arbault & Boutin, 1968; Arbault & Lacroix-Boutin, 1969; Arbault & Lacroix, 1971; Wallace, P. D. & Pleasants, C. A., duplicated ICES meeting paper CM 1972/J: 8), and is further demonstrated by Demir & Southward (1974) in discussing the results of a study of small scale seasonal changes in spawning intensity in inshore waters.


Author(s):  
A. T. Grevtsova ◽  
T. B. Vakulenko ◽  
N. S Nоnischenko

The main task of the expeditions was the search for the following species of natural Siberian flora and theintroduction of live plants and seeds to the Botanical Garden named after acad. A. V. Fomin: Cotoneaster mongolicus.C. neo-popvii, C. tjulinae, which are currently presented in our collection. In addition, long-term phenological observations in the conditions of the north-west of Ukraine allowed to isolate new species from the imported material: C. kyachticus.C. logginovii. They are described in the materials of the XIV and XVII conferences “Problems of botany of Southern Siberiaand Mongolia”. A trip to the lake Zun-Torei was dedicated to the search for C. mongolicus. As it turned out later, under theC. mongolicus mother’s plant, we dug up a plant different from the mother’s plant, to which we gave the name C. logginovii.This article provides materials to identify the parents pair in the formation of this hybrid pitchfork. For this purpose,materials of herbarium collections from the vicinity of the lake were used Zun-Torei experienced local botanists, as wellas personal fees. Comparison of the samples allowed to establish their identity with C. mongolicus, as well as to certify it asone of the parents of C. logginovii. Morphological descriptions of annual shoots leaves, flowers, fruits, seeds of three typesof Cotoneasters: C. megalocarpus, C. mongolicus, C. yakuticus; micrographs of endocarp of bones of the previous speciesand C. logginovii, C. melanocarpus, C. uniflorus are given. The herbarium samples of C. mongolicus collected in the areaof the lake Zun-Torey were analyzed. The material is illustrated with photographs of plants introduced in the north-westof Ukraine (Kiev). The introduction of plants by the method of genus complexes by F. N. Rusanov allowed to create theCotoneaster collection, which includes 200 taxa of the genus. In the Botanical Garden named after acad. A .V. Fomin fromthe flora of Siberia preserved 11 species of Cotoneaster: C. commixtus, C. kyachticus. C laxiflorus. C. logginovii, C. lucidus,C. neo-popovii, C. megalocarpus, C. mongolicus, C. tjulinae, C. uniflorus, C. yakuticus.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chuang Zhang ◽  
Wenxu Dong ◽  
Kiril Manevski ◽  
Wenpei Hu ◽  
Arbindra Timilsina ◽  
...  

AbstractThe enzymatic activities and ratios are critical indicators for organic matter decomposition and provide potentially positive feedback to carbon (C) loss under global warming. For agricultural soils under climate change, the effect of long-term warming on the activities of oxidases and hydrolases targeting C, nitrogen (N) and phosphorus (P) and their ratios is unclear, as well as whether and to what extend the response is modulated by long-term fertilization. A 9-year field experiment in the North China Plain, including an untreated control, warming, N fertilization, and combined (WN) treatment plots, compared the factorial effect of warming and fertilization. Long-term warming interacted with fertilization to stimulate the highest activities of C, N, and P hydrolases. Activities of C and P hydrolase increased from 8 to 69% by N fertilization, 9 to 53% by warming, and 28 to 130% by WN treatment compared to control, whereas the activities of oxidase increased from 4 to 16% in the WN soils. Both the warming and the WN treatments significantly increased the enzymatic C:N ratio from 0.06 to 0.16 and the vector length from 0.04 to 0.12 compared to the control soil, indicating higher energy and resource limitation for the soil microorganisms. Compared to WN, the warming induced similar ratio of oxidase to C hydrolase, showing a comparable ability of different microbial communities to utilize lignin substrates. The relationship analyses showed mineralization of organic N to mediate the decomposition of lignin and enzyme ratio in the long-term warming soil, while N and P hydrolases cooperatively benefited to induce more oxidase productions in the soil subject to both warming and N fertilization. We conclude that coupled resource limitations induced microbial acclimation to long-term warming in the agricultural soils experiencing high N fertilizer inputs.


Author(s):  
I. B. Uskov ◽  
◽  
K. G. Moiseyev ◽  
M. V. Nikolaev ◽  
O. V. Kononenko ◽  
...  

Purpose: to analyze the soil-climatic and anthropogenic reasons of decreasing drainage efficiency of closed pottery tubular drainage on the reclaimed lands of the North-West of Russia under the observed local weather conditions against the background of global climate changes. Materials and methods. The objects of research are seasonal precipitation regimes, reclaimed lands and drainage systems of closed tubular drainage. The methods of applied mathematical statistics, the ensemble method of processing and generalization of climate forecasts of the Intergovernmental Panel on Climate Change (IPCC), modernized by the authors were used in research. Monitoring data on changes in the physical properties of soils of reclaimed lands during their long-term operation were obtained using laboratory agrophysical methods for studying samples taken in the field. Results. It is shown that under the conditions of the observed climatic changes, the frequency, intensity and extremeness of atmospheric precipitation are increased. Long-term exploitation of lands with a leaching drainage regime is accompanied by changes in the hydrophysical properties of soils, for example, the coefficient of heterogeneity of the subsurface horizons of soils texture of automorphic genesis decreased from 26 to 6. The system “precipitation – soil – drainage” in climatically abnormal weather conditions exceeding the initial calculated precipitation level mode by 10–20 %, is unable to ensure the removal of excess moisture from the root layer. Conclusions: when creating and reconstructing such reclamation drainage systems it is recommended to take into account the tendencies of changes in the spatial-temporal statistical structure of precipitation and to design technologies for regulating the water regime with systems for intercepting and diverting surface runoff on such reclaimed lands.


Author(s):  
Xonné Haywood ◽  
Anita Elizabeth Pienaar

Poor socio-economic status contributes to undernutrition which, in turn, can increase the risk of academic underachievement. This study wants to determine if stunting, being underweight, and thinness show long term relations with academic performance in primary school girls aged 6 to 13 in the North West province of South Africa. A randomized and stratified longitudinal research design including a baseline and two time-point measurements over seven school years was used. The sample included girls aged 6 to 13 years (N = 198) in the North West province of South Africa. Academic performance in the June school assessments and national and provincial assessments in grades 1, 4, and 7 were used to determine academic performance. Independent t-testing was used to determine differences between thinness, underweight and stunted girls as opposed to a reference group with no undernutrition indices. A repeated measures ANOVA and post hoc Bonferroni adjustment analyzed relations over time. Normal weight girls significantly outperformed stunted girls academically (p < 0.05) over time. Stunting had prolonged and significant negative influences on language, mathematics, and grade point average (p < 0.05). Early identification of undernutrition, especially stunting, is important for intervention and the implementation of timely prevention strategies, especially during early childhood years.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Mofor Nelson Alakeh ◽  
Njoyim Estella Buleng Tamungang ◽  
Mbene Kenneth ◽  
Yuhinwenkeh Njumbo Blaise ◽  
Nchofua Festus Biosengazeh

This study assessed some physicochemical and trace element properties of soils and Zea mays from farmed dumpsites in the Bamenda metropolis, North-West Cameroon. The growth in population and metal workshops in Bamenda has resulted in the dumping of large quantities of wastes on agricultural soils. Thus, the fear of these agricultural soils and crops being contaminated by waste dumped on them is a call for concern because most of the populations rely on agriculture for survival. A soil and Zea mays sample each was collected from three farmed dumpsites (Nkwen, Mankon, and Bamendakwe) in the Bamenda metropolis and analyzed for physicochemical and trace element properties using standard procedures. The results of physicochemical analysis revealed that the soils had pH values ranging from 5.63 to 7.49, average organic matter, low total nitrogen, high C/N ratio, and high CEC, and the soil textural class was clay loam for soils of Nkwen and sandy loam for soils of Mankon and Bamendakwe. The content of bases in Zea mays was high compared to those in the soil. The concentration of Fe (14635.6 µg/g) in soils of Bamendakwe and Cu (157.17 µg/g) and Zn (1438.36 µg/g) in soils of Mankon had values which were above the permissible limit. The concentration of Zn (114.48 µg/g) in the plant sample of Mankon together with the concentration of Fe in all three plant samples had values above permissible limits. Natural origins and domestic waste were identified as the major sources of trace metals in the soils. Thus, there are potential health hazards related to consuming crops from such soils. Bioremediation techniques can be used to recover heavy metals from such soils. Furthermore, the mobilization of nutrient ions and immobilization of heavy metals by induced liming could be important in sustainable agricultural production and soil environmental protection of the soils studied.


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