A greenhouse experiment was performed to evaluate effectiveness of goosegrass (Eleusine indica) in phytoremediation of soil contaminated with 8,247 mg kg⁻¹ of total petroleum hydrocarbons (TPH). We determined seed germination toxicity, soil microbial viable counts, catalase activity, dehydrogenase activity (DHA), and the concentrations of TPH and 14 polycyclic aromatic hydrocarbons (PAHs) in soil and plant tissue. After 5 months, the initial level of contamination was reduced by 47% in planted soil, whereas it was only reduced by 11% in nonplanted soil. Bacterial numbers were 72 times greater in the rhizosphere treated soil than in the unvegetated treatment at the end of the study. There was no correlation between microbial counts or DHA and catalase activity, and the correlation between microbial counts and DHA was weak. Significant chemical reduction of H₂O₂, caused by the soil fabric, was observed in the determination of catalase activity. In case of vegetated treatment, 32% of PAHs was removed, but only 5% of PAHs was dissipated in the unvegetated pots. Gas chromatography/mass spectrometry analysis of plant tissue indicated that a low amount of PAHs (25.50 mg kg⁻¹ dry biomass) was detected in goosegrass roots growing in the contaminated soil, and no uptake into the shoots was occurring.

Most alpine ecosystem climate change studies identify changes in biota, several report abiotic factors and conditions, few report temperature changes, and few to none discuss growing degree days (GDD) changes. This study provides results of data analysis on changes in number of GDD in the alpine desert of the San Luis Valley (SLV) whose community is dominated by an irrigated agricultural region. Analysis indicates significant increases (p < 0.05) in annual and growing season GDD₁₀, GDD₄.₄ (potato), and GDD₅.₅ (alfalfa) during 1994-2007 compared to 1958-1993. With one exception, all stations experienced significant increases in mean annual daily GDD between 0.12 and 0.50 day⁻² and growing season GDD day⁻² 0.21 and 0.81. Higher temperatures increase numbers of GDD, quickening growth of crops and maturity at the cost of reduced yield and quality. Increases in GDD indicate the Valley's agricultural region and economy may experience negative impacts as yields decrease and water use increases.

Soil contamination may contribute to forest decline, by altering nutrient cycling and acquisition by plants. This may hamper the establishment of a woody plant cover in contaminated areas, thus limiting the success of a restoration program. We studied the nutritional status of planted saplings of Holm oak (Quercus ilex subsp. ballota (Desf.) Samp.), white poplar (Populus alba L.), and wild olive tree (Olea europaea var. sylvestris Brot.) in the Guadiamar Green Corridor (SW Spain) and compared it with established adult trees. Soils in this area were affected by a mine-spill in 1998 and a subsequent restoration program. The spill resulted in soil acidification, due to pyrite oxidation, and deposited high concentrations of some trace elements. In some sites, we detected a phosphorus deficiency in the leaves of Q. ilex and O. europaea saplings, as indicated by a high N:P ratio (>16). For O. europaea, soil contamination explained 40% of the variability in leaf P and was negatively related to chlorophyll content. Soil pH was a significant factor predicting the variability of several nutrients, including Mg, P, and S. The uptake of Mg and S by P. alba was greater in acidic soils. The monitoring of soil pH is recommended since long-term effects of soil acidification may negatively affect the nutritional status of the trees.

The arsenic contamination of Bangladesh groundwater involves heavy arsenic inputs to irrigated rice fields. Beside adsorption on soil colloids, iron-arsenic co-precipitation phenomena can affect arsenic retention in soils. In paddy fields of Satkhira District, Bangladesh, the study of the arsenic and iron forms in the irrigation waters and in soils at different times and distances from the irrigation well evidenced that a higher Fe/As ratio in the well water was related to a faster oxidation of Fe(II) and As(III) in water and to a close Fe-As association in soils, together with a greater accumulation of arsenic and poorly ordered iron oxides. The concentration of arsenic and of labile iron forms decreased with the distance from the well and with the depth, as well as the reversibility of arsenic binding. The fate of the arsenic added to the soils by irrigation hence resulted strongly influenced by iron-arsenic co-precipitation, depending on the Fe/As ratio in water. Irrigation systems favouring the sedimentation of the Fe-As flocks could help in protecting the rice from the adverse effects of dissolved arsenic.

Thais gradata samples were collected from six locations along the southern shores of Peninsular Malaysia and analyzed for imposex incidence and organotin (butyltins (BTs), including tributyltin, dibutyltin, and monobutyltin, and phenyltins (PTs), including triphenyltin, diphenyltin, and monophenyltin concentrations), in tissue burden. On average, the BT levels were found to be higher than the levels reported a year before for other biota. In contrast, the PT compounds were found to be lower than in the previous report. The present study also classified the morphological expressions of the imposex scheme for this species into seven stages (stage 0 to stage 6) by observing the development of vas deference sequence (VDS) and penis bulk. This latest imposex scheme clearly indicates the mechanism of VDS growth, the structural changes from penis bulk to a penis with flagellum, and from a normal vaginal opening to a swollen vaginal opening. The degree of imposex was assessed using the vas deference sequence index and the percentage of females possessing the imposex characteristics. It was found that locations possessing high imposex levels also tended to show high BT levels in the snail tissue samples. However, correlation analysis did not show a significant relationship among the two parameters. A better result could be obtained if more samples and sampling locations were added in order to prove the hypothesis. The nonsignificant correlation between the shell height and any of the organotin compounds, along with no significant differences between BT levels in female and lower imposex stage samples, suggests that the BT concentration detected was a recent contamination.

Rates of biosorption of cadmium and copper ions by nonliving biomass of the brown macroalga Sargassum sinicola under saline conditions were studied. Batch experiments show that the ability to remove cadmium is significantly diminished (from 81.8% to 5.8%), while the ability to remove copper remains high (from 89% to 80%) at a range of salinity from 0 to 40 psu. Maximum capacity of biosorption at 35 psu was 3.44 mg g⁻¹ for cadmium and 116 mg g⁻¹ for copper. The presence of salt did not significantly affect the rate of biosorption, which was about 90% of saturation in 60 min for both metals. There is an antagonistic effect on biosorption when both metals are present in the solution.

An outdoor pot experiments was conducted to investigate the effects of enhanced ultraviolet-B (UV-B) radiation on nitrous oxide (N₂O) emissions from soil-winter wheat systems. The enhanced UV-B radiation treatments were simulated by 20% increase in its intensity. N₂O fluxes were measured with a static opaque chamber-gas chromatograph method. The results showed that enhanced UV-B radiation did not change the seasonal patterns of N₂O emissions. Compared to the controls, the enhanced UV-B radiation reduced N₂O fluxes by 16.4% (p = 0.015) during the elongation-booting stage, while it had no significant effects on N₂O fluxes in the turning-green and heading-maturity phases. During the turning green-overall heading span, the accumulative N₂O was largely decreased by the enhanced UV-B radiation (p < 0.05). From the overall heading to maturity, however, the effects of enhanced UV-B on N₂O emissions were not pronounced (p > 0.10). At the elongation-booting stage, enhanced UV-B increased soluble proteins content in leaves, NO ₃ ⁻ -N and NO ₄ ⁺ -N content in rhizosphere soil, and soil microbial biomass C (C mic) and N (N mic; p < 0.05), as well as microbial biomass C:N ratio changing from 5.0 to 6.8. Our findings suggest that the effects of enhanced UV-B radiation on N₂O emissions differed with winter wheat developmental stages. To assess the overall effects of enhanced UV-B radiation on N₂O emissions from agroecosystems, nevertheless, more field measurements deserve to be carried out in various cropping systems.

Distribution of ¹³⁷Cs and ²³⁹,²⁴⁰Pu in the forest soils horizons of the Opole Anomaly was established. Gamma and alpha spectrometry was used for determination of these isotopes. It was found that the ¹³⁷Cs activity was approx. 1,000 times higher than that of ²³⁹,²⁴⁰Pu. The highest activities of both radioisotopes were found close to the boundary region in soil profile where the organic horizon turns into the inorganic one. Cluster analysis did not clearly indicate the group's existence in data in respect to ¹³⁷Cs and ²³⁹,²⁴⁰Pu activities and organic matter content. Distributions of ¹³⁷Cs and ²³⁹,²⁴⁰Pu in soil horizons were non-normal but similar to each other. These distributions were substantially different from that one for organic matter content. The data were separated into two groups, for organic and inorganic soil horizons, respectively. Data transformation using Box-Cox formula was performed following by standardization. Mutual relationships between variables were investigated using ordinary and robust regression methods. Good correlation between ¹³⁷Cs and ²³⁹,²⁴⁰Pu was found. No significant relationship between organic matter content and radioisotopes activity was asserted.

Mercury pollution in the Second Songhua River (SSR) was serious in the last century due to effluent from a chemical corporation. Effects of riverine self-purification on mercury removal were studied by comparing monitoring data of mercury concentrations varieties in water, sediment, and fish in the past, about 30 years. The present work suggested that a river of such a size like the SSR possessed the potential ability to recover from mercury pollution under the condition that mercury sources were cut off, though it needs a very long time, which might be several decades or even a century of years. During the 30 years with no effluent containing mercury input, total mercury (T-Hg) of water and sediment in some typical segments, mostly near the past effluent outlet, had decreased radically but still higher than the background values, though the decrease amplitudes were over 90% compared with that in 1975. T-Hg had decreased by more than 90% in most fishes, but some were still not suitable for consumption. Methylmercury concentrations (MeHg) of water, sediment, and fish were higher or close to the background levels in 2004. In the coming decades, the purification processes in the SSR would be steady and slow for a long period.

The Northern Patagonian Andean range shared by Chile and Argentina has numerous glacial oligotrophic lakes protected in a series of National Parks. Recent baseline surveys indicated that concentrations in muscle and liver tissues from various fish species from across Nahuel Huapi and Los Alerces National Parks in Argentina were comparable or higher than similar fish species from other parts of the world. As a result, Lake Moreno, in Nahuel Huapi National Park, was chosen to investigate multiple element sinks, trends, and transfer in a representative Patagonia aquatic food web. The metals and metalloids Ag, As, Ba, Br, Cs, Co, Cr, Fe, Hg, K, Na, Rb, Se, and Zn were analyzed in three size plankton fractions, submerged macrophytes, biofilm, insect larvae, amphipods, decapods, gastropods (snails), annelids (earthworms), and forage fish. Except for nanoplankton (10-53 μm; small-celled algae, rotifers) and microplankton (53-200 μm; larger algae, ciliates, zooplankton nauplii), which share elemental compositional similarities, each taxon category had its own distinctive compositional pattern, revealed by principal component analysis. Nano- and microplankton tend to be relatively elevated in some metals, including As, Co, Cr, Fe, Hg, Zn, and Rb, followed by biofilm. Shredder-scrapper Trichoptera (caddisflies) have higher concentration of most of the studied elements than other insect larvae taxa, especially carnivorous Odonata (Anisoptera, dragonflies), which were associated with lower elemental contents. Those trends point to an overall tendency for biodiminishing element concentrations with trophic level in the benthos of Lake Moreno.