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1.
This study performed on randomly selected seven sample plots in leguminous black locust (Robinia pceudoacacia L.) plantations and five sample plots in umbrella pine (Pinus pinea L.) plantations on coal mine soil/spoils. Soil samples were taken from eight different soil depths (0–1, 1–3, 3–5, 5–10, 10–20, 20–30, 30–40, and 40–50 cm) into the soil profile. On soil samples, bulk density, fine soil fraction (Ø < 2 mm), sand, silt and clay rates, soil acidity (pH), organic carbon (Corg), and total nitrogen (Nt) contents were investigated. Also, some forest floor properties (unit mass, organic matter, and total nitrogen) were determined, and results were compared statistically between umbrella pine and black locust. As a result, 17 years after plantations, total forest floor accumulation determined as 6,107 kg ha???1 under black locust compared to 13,700 kg ha???1 under umbrella pine. The more rapid transformation of leguminous black locust forest floor creates organic carbon that migrates further into the mineral profile, and rapid accumulation of C and N in the soil profile was registered. Slower transformation processes of forest floor under umbrella pine result in lower soil N ratio and greater quantity of forest floor. Higher soil pH under leguminous black locust was determined significantly than umbrella pine. In conclusion, the composition of symbiotic nitrogen fixation of black locust appears to be a possible factor favoring carbon and nitrogen accumulation and, consequently, soil development. Clearly, both tree species have favorable impacts on initial soil formation. The umbrella pine generates the more forest floor layer; in contrast, black locust forest floor incorporates into the soil more rapidly and significantly increases soil nitrogen in upper soil layers.  相似文献   

2.
Visitor’s access to understorey vegetation in park forest stands results in the impoverishment of plant species composition and a reduction in habitat quality. The phenomenon of biotic homogenisation is typical in urban landscapes, but it can proceed differently depending on the scale, a detail that has not been observed in previous studies. This research was carried out in seven Warsaw parks (both public and restricted access). Thirty-four forested areas were randomly selected, some subjected to strong visitors’ pressure and some within restricted access areas, free of such impacts. The latter category included woodlands growing in old forest and secondary habitats. Public access to the study areas contributed to the disappearance of some forest species and their replacement by cosmopolitan non-forest species, leading to loss of floristic biodiversity in areas of high ecological importance at the city scale. Some human-induced factors, including soil compaction and changes in soil pH, moisture and capillary volume, were found to cause habitat changes that favoured native non-forest plants. Despite changes in species composition, the taxonomic similarity of understorey vegetation in both categories—public access and restricted access—was comparable. In a distance gradient of measurements taken around selected individual trees, there was found to be significant variation (in light, soil pH and compaction) affecting the quality and quantity of understorey vegetation (including rare species). In conclusion, the protection of rare forest species could be achieved by limiting access to forested areas, particularly in old forest fragments, and we highly recommend its consideration in the proposal of future park restoration plans.  相似文献   

3.
The lead–zinc industry in the Bukowno region of southern Poland has polluted the surface layer of the surrounding soils mainly with lead (Pb), cadmium (Cd), zinc (Zn), arsenic (As), and thallium (Tl). Analysis of six soil profiles, taken on the east side of the postflotation waste site of the Mining and Metallurgical Plants ZGH "Boles?aw" in Bukowno, showed that they were podzol soils, taking form of loose sands with neutral pH and reducing conditions. Concentration of organic matter in the horizons ranged from 2 to 80 %. The main components of the mineral soil were quartz, carbonates, K-feldspars, plagioclases, and micas (sericite). The highest total concentrations of metals were found in the O, A, and B horizons. Over 90 % of the Cd content, 80 % of the Pb content, 60 % of the Zn content, ~60 % of the Tl content, and 20 % of the As content occurred as mobile forms. The corresponding total concentrations were 10 mg/kg Cd, 922 mg/kg Pb, 694 mg/kg Zn, <1 mg/kg Tl, and <5 mg/kg As. This can potentially be taken up from the soil and transported in the trophic chain. Comparing the total metal content with the legal limits in Poland, it is observed, that the investigated soils exceeded the permissible levels of Cd, Pb, and Zn for agricultural soils. Arsenic and Tl are not reflected in the chemical quality of soil classifications.  相似文献   

4.
The presence of vegetation in stream ecosystems is highly dynamic in both space and time. A digital photography technique is developed to map aquatic vegetation cover at species level, which has a very high spatial and a flexible temporal resolution. A digital single-lens reflex (DSLR) camera mounted on a handheld telescopic pole is used. The low-altitude (5 m) orthogonal aerial images have a low spectral resolution (red-green-blue), high spatial resolution (~1.9 pixels cm?2, ~1.3 cm length) and flexible temporal resolution (monthly). The method is successfully applied in two lowland rivers to quantify four key properties of vegetated rivers: vegetation cover, patch size distribution, biomass and hydraulic resistance. The main advantages are that the method is (i) suitable for continuous and discontinuous vegetation covers, (ii) of very high spatial and flexible temporal resolution, (iii) relatively fast compared to conventional ground survey methods, (iv) non-destructive and (v) relatively cheap and easy to use, and (vi) the software is widely available and similar open source alternatives exist. The study area should be less than 10 m wide, and the prevailing light conditions and water turbidity levels should be sufficient to look into the water. Further improvements of the image processing are expected in the automatic delineation and classification of the vegetation patches.  相似文献   

5.
This paper describes the chemistry of porewater when constructing different soil layers on acidic weathered rock of a closed mine to remediate the surface environment. Three cases were set on a flat surface of the site, all under different layer systems. Case 1 was only composed of weathered rocks. A top neutralization layer was constructed on the weathered rocks in case 2, whereas both an upper low-permeable and middle neutralization layers were constructed on the weathered rocks in case 3. The low-permeable layer of 30?cm thick consists of clay, and the neutralization layer of 30?cm thick consists of the mixture of the weathered rock and calcium carbonate as a neutralizer. Porewater sampling systems and soil sensors to measure temperature, water content, and electrical conductivity were set at different depths. In case 1, steadily high concentrations of heavy metals were observed regardless of the depth, and the pH ranged from 2 to 4. In cases 2 and 3, a dramatic decrease in concentrations of heavy metals was observed, even below the neutralization layer. For both cases, pH values were circumneutral. There were no significant seasonable changes in heavy metals concentrations and pH of porewater by considering the temperature and precipitation. In addition, the water content of the layers in case 3 fluctuated more mildly than that in cases 1 and 2, indicating that the low-permeable layer reduced the rate of infiltration. Therefore, a significant reduction in the load of heavy metals released from the site can be achieved by both implementing neutralization and low-permeable layers.  相似文献   

6.
An economic and quick methodology for performing a preliminary spatial assessment of a city air quality with the purpose to identify locations and zones susceptible to high pollution levels is proposed. A Patras case-study is selected, regarding the air pollutants of sulfur dioxide (SO2) and oxides of nitrogen (NOx). A total number of 451 samples of short duration, of which 225 were randomly picked in morning rush hours and 226 within evening rush hours, were collected from 50 locations of the major Patras area during a year period, when peaks of primary air pollutants usually occur. Concentration measurements at prescribed locations used to statistically calculate spatial average concentrations approximating 1-h mean values with mean probable errors less than 25.9% for SO2, NO and NOx and less than 15.5% for NO2. Then iso-concentration contour diagrams plotted indicate high pollution zones and possibly appropriate locations for continuous or random monitoring according to the European Community (EC) Directives. The 1-h mean concentrations were in good correlation to the corresponding traffic rates and useful relationships are given (0.54 ≤ r ≤ 0.63). In addition, comparisons with data available for other cities, as well as with the limit and guide values provided by the EC and the World Health Organization (WHO) were given. The present data could be useful for the design and optimization of a city network of stations for monitoring air quality, for environmental impact assessments, future reference and comparisons due to city development needs, as well as for validating dispersion models.  相似文献   

7.
Ozone dynamics in our study area (Castellon, Spain) is both strongly bound to the mesoscale circulations that develop under the effect of high insolation (especially in summer) and conditioned by the morphological characteristics of the Western Mediterranean Basin. In this work we present a preliminary analysis of ozone time series on five locations in Castellon for the period 1997–2003. We study their temporal and spatial variations at different scales: daily, weekly, seasonally and interannually. Because both the O3 concentration and its temporal variation depend on the topographic location of the observing station, they can show large differences within tens of kilometer. We also contrast the variation in the ozone concentration with the variations found for meteorological variables such as radiation, temperature, relative humidity and recirculation of the air mass. The link between elevated ozone concentrations and high values of the recirculation factor (r=0.7–0.9) shown the importance of recirculating flows on the local air pollution episodes.  相似文献   

8.
The concentration of mercury was determined in samples of the lichen Hypogymnia physodes, the moss Pleurozium schreberi, and the soil humus collected in Polish and Czech Euroregions Praded and Glacensis. The sampling sites were located in Bory Stobrawskie, Bory Niemodlińskie and Kotlina K?odzka in Poland, and in Jeseniki and Gory Orlickie in the Czech Republic. The mean concentrations of mercury accumulated in the lichen (0.129?mg?g(-1)), in the moss (0.094?mg?g(-1)) and in soil (0.286?mg?g(-1)) were fairly close to the corresponding concentrations in other low-industrialized regions. The highest concentrations of mercury were observed in the lichen and the moss samples from Kotlina K?odzka. The primary deposition of mercury was evaluated using the comparison factor, defined as the ratio of a difference between the concentrations of a bioavailable analyte in lichens and in mosses, to the arithmetic mean of these concentrations.  相似文献   

9.
The objective of this study was to examine the effects of vegetation change from a native broadleaf forest to a coniferous plantation on selected soil properties, including soil texture, pH, organic matter, total nitrogen (N), total phosphorus (P), exchangeable cations (Ca2+, K+, Na+), and cation exchange capacity (CEC). Results showed that the amount of clay particles, Ca2+, and K+ values significantly increased, whereas Na+, total N, and organic matter and soil pH values decreased on the treatment plot after vegetation change. Soil acidity also increased and soil textural group changed from moderately fine-textured soils (clay loam) to medium-textured soils (loam) under both control and treatment plots. Organic matter, total N, and Na+ values increased, whereas Ca2+ concentration decreased through time on the control plot. Soil pH, total P, K+, and CEC did not show significant changes through time on the control plot.  相似文献   

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11.
Methane (CH4) emissions and oxidation were measured at the Air Hitam sanitary landfill in Malaysia and were modeled using the Intergovernmental Panel on Climate Change waste model to estimate the CH4 generation rate constant, k. The emissions were measured at several locations using a fabricated static flux chamber. A combination of gas concentrations in soil profiles and surface CH4 and carbon dioxide (CO2) emissions at four monitoring locations were used to estimate the CH4 oxidation capacity. The temporal variations in CH4 and CO2 emissions were also investigated in this study. Geospatial means using point kriging and inverse distance weight (IDW), as well as arithmetic and geometric means, were used to estimate total CH4 emissions. The point kriging, IDW, and arithmetic means were almost identical and were two times higher than the geometric mean. The CH4 emission geospatial means estimated using the kriging and IDW methods were 30.81 and 30.49 g m?2 day?1, respectively. The total CH4 emissions from the studied area were 53.8 kg day?1. The mean of the CH4 oxidation capacity was 27.5 %. The estimated value of k is 0.138 year?1. Special consideration must be given to the CH4 oxidation in the wet tropical climate for enhancing CH4 emission reduction.  相似文献   

12.
The aim of this study was to investigate the spatial distribution of heavy metal in soil and evaluate the dissolution of metal from soil to ponded-surface water, leaching through soil profiles and metal uptake in grass as related to different land-use practices. The data provided a scientific basis for best-management practices for land use in Khli Ti watershed. The watershed has a Pb-contamination problem from the previous operation of a Pb-ore concentrator and abandoned Zn–Pb mine. Sampling sites were selected from a land-use map, with land-use types falling into the following four categories: forest, agricultural land, residential area and road. Soil, ponded-surface water, grass samples and soil profiles were collected. The study related soil characteristics from different land-use practices and locations with observed metal concentrations in ponded-surface water and soil. High enrichment factors of Pb and As in soil were found. Partitioning coefficient, Kd values were in the order: Cr > Pb > Ni > Cu > Cd > Zn. Soil disturbance from land-use activities including tillage and traffic increased leaching of trace metal from soils. Pb in soil was significantly taken up by grass even though the Transfer Factor, TF values were rather low. Agricultural activities in the watershed must be limited. Moreover, land encroachments in the upper and middle part of the watershed which have high potential of Pb must be strictly controlled in order to reduce the Pb contamination from non-point sources.  相似文献   

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Total mercury (Hg) concentrations were determined by CV-AAS in selected tissues (liver, kidney, and muscle) of the Great Cormorant and some fish species (herring, ruffe, European smelt, tench, roach, Crucian carp, and Prussian carp) from the Vistula Lagoon ecosystem (Poland). Significant correlations between Hg concentrations in the kidneys and muscle of cormorants (U test, p?<?0.05) were found; levels of the metal were highest in the birds?? liver and kidneys. Total Hg concentrations in the fish decreased in the following order: roach > Prussian carp > Crucian carp > tench > European smelt > ruffe > herring. The biomagnification factor of Hg for the cormorant relative to the fish decreased in the following sequence: herring > ruffe > European smelt > tench > Crucian carp > roach = Prussian carp. It was significantly greater than unity, especially for the cormorant?Cherring trophic relationship. This implies that Hg is biomagnified in the cormorant in relation to its prey.  相似文献   

15.
Large-scale ecosystem restoration efforts, such as those in the Florida Everglades, can be long-term and resource intensive. To gauge success, restoration efforts must have a means to evaluate positive or negative results of instituted activities. Edaphic properties across the Everglades landscape have been determined to be a valuable metric for such evaluation, and as such, a baseline condition from which to make future comparisons and track ecosystem response is necessary. The objectives of this work were to document this baseline condition in the southern most hydrologic unit of the Everglades, Everglades National Park (ENP), and to determine if significant eco-partitioning of soil attributes exists that would suggest the need to focus monitoring efforts in particular eco-types within the ENP landscape. A total of 342 sites were sampled via soil coring and parameters such as total phosphorus (TP), total nitrogen (TN), total carbon (TC), total calcium, total magnesium, and bulk density were measured at three depth increments in the soil profile (floc, 0-10 cm, and 10-20 cm). Geostatistical analysis and GIS applications were employed to interpolate site-specific biogeochemical properties of soils across the entire extent of the ENP. Spatial patterns and eco-type comparisons suggest TC and TN to be highest in Shark River Slough (SRS) and the mangrove interface (MI), following trends of greatest organic soil accumulation. However, TP patterns suggest greatest storages in MI, SRS, and western marl and wet prairies. Eco-partitioning of soil constituents suggest local drivers of geology and hydrology are significant in determining potential areas to focus monitoring for future change detection.  相似文献   

16.
Physico-chemical analysis of soil samples at an oil spill site in the Niger Delta Area of Nigeria showed that the total hydrocarbon content of top soil layers ranged from 0.8 to 12.4 ppm in the heavy impact zone and the oil had penetrated to a depth of 7.2 m. Hydrocarbon concentration in the medium impact zone ranged from 0.02 to 0.40 ppm while hydrocarbons were not detected in 75% of samples from the unimpacted reference zone. Measurement of heavy metal concentrations in the soils revealed a significant build-up (p<0.05) of lead, iron and zinc in the heavy impact zone. Other parameters including electrical conductivity, exchangeable cations, available phosphorus and total nitrogen in impacted soils were comparatively low while the total organic carbon was high, compared with the reference site. Textural class of soil from the different depths showed a predominantly brown sand at the top soil, loamy sand at medium depths and grey coarse sand at greater depths.  相似文献   

17.
The growth of Scots pine and its suitability for afforestation of post-mining landscapes in Northeast Estonia were assessed in comparative analytical studies by using morphological parameters and mineral nutrition characteristics. The growth and nutrient uptake of Scots pine growing on post-mining substrate were compared with the characteristics of pines of the same age (22–23 years) in a Calluna forest site type predominant in North Estonia in similar climatic zone. Results of the analyses of soil upper layers showed that the concentration of N and P in soil did not differ between the opencast spoil and Calluna site, but significantly higher pH of soil and concentrations of K, Ca, and Mg were found in mine spoil. The concentrations of K and Mg in needles were significantly higher in the post-mining area, but the concentrations of N, P, and Ca did not differ significantly. Comparison of the needle nutrient concentration with the standard for optimum concentrations revealed P deficit in the post-mining area and P and K deficit in the Calluna site. Scots pine formed longer and thinner needles and shoots in the post-mining substrate than in the Calluna site. It was assumed that in the post-mining area the growth of pines is predominantly dependent on K and Ca concentrations in their tissues as the biomass of needles was strongly correlated with the K/Ca ratio, whereas the biomass in the Calluna site was correlated with the N/P ratio. The height and diameter of trees were significantly larger in the post-mining area.  相似文献   

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The effects of land use and soil properties on total and available Cu concentrations in soils were investigated in this study. A total of 276 surface (0-20 cm) soil samples were collected from seven land uses: industrial area, woodland, vegetable field, dry land, paddy field, tea garden and orchard. The total and available (DTPA extractable) Cu concentrations, pH, organic matter, and total nitrogen contents, and cation exchange capacity were measured for each sample. The correlation and ANOVA analyses showed that land use significantly affected total and available Cu concentrations, and the available ratio of soil Cu (available Cu concentration/total Cu concentration). On total Cu concentration, total nitrogen had significant influence in dry land and paddy field, and CEC in garden land; on available Cu concentration, the four measured soil properties showed significant influence only in paddy field; on the available ratio of Cu, pH had significant effect in paddy field and woodland, and CEC in industrial area. Moreover, the relationship between available Cu concentration and soil properties was constructed in different land uses. Spatial analysis of grain Cu using indicator Kriging showed that most of the study areas were in low risk for arable activities, and 7.94% of the study area and 5.10% of the arable land were in high risk probability.  相似文献   

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