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Trace element soil pollution can have ecotoxic effects on plants, which could negatively affect the restoration of a degraded area. In this work, we studied the revegetation success in different sites within a trace element-polluted area (Guadiamar River Valley, SW Spain). We analysed the survival and growth patterns of afforested plants of seven Mediterranean woody species, and their relation to soil pollution, over 3 years. We also analysed the trace element accumulation in the leaves of these species. The area was polluted mainly by As, Cd, Cu, Pb and Zn (soil total concentrations up to 250, 3.6, 236, 385 and 510 mg kg−1, respectively). The woody plant performance was very different between sites and between species; in the riparian sites, plant survival rates were nearly 100%, while in the upland terrace sites species such as Quercus ilex and Ceratonia siliqua showed the lowest survival rates (less than 30%) and also the lowest relative growth rates. There were no significant relationships between plant performance and soil pollution in the riparian sites, while in the upland sites mortality, but not growth, was related to soil pollution, although that could be an indirect effect of different substrate alteration between sites. The accumulation of soil pollutants in the studied plants was low, with the exception of Salicaceae species, which accumulated Cd and Zn in the leaves above 1 and 200 mg kg−1, respectively. We discuss the results with regard to the afforestation of trace-element polluted areas.  相似文献   
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Crop rotation adoption in no‐tillage systems (NTS) has been recommended to increase the biological activity and soil aggregation, suppress soil and plant pathogens, and increase the productivity aiming at the sustainability of agricultural areas. In this context, this study aimed to assess the effect of crop rotation on the arbuscular mycorrhizal fungi (AMF) community and soil aggregation in a soil cultivated for nine years under NTS. Treatments consisted of combinations of three summer crop sequences and seven winter crops. Summer crop sequences consisted of corn (Zea mays L.) monoculture, soybean (Glycine max L. Merrill) monoculture, and soybean–corn rotation. Winter crops consisted of corn, sorghum (Sorghum bicolor (L.) Moench), sunflower (Helianthus annuus L.), sunn hemp (Crotalaria juncea L.), pigeon pea (Cajanus cajan (L.) Millsp.), oilseed radish (Raphanus sativus L.), and millet (Pennisetum americanum (L.) Leeke). Soil samples were collected at a depth of 0–0.10 m for analyses of soil chemical, physical, and biological attributes. Spore abundance, total glomalin, and soil aggregate stability index were higher in the soil under corn monoculture. The highest values of aggregate mean weight diameter were observed in the soybean–corn rotation (3.78 mm) and corn monoculture (3.70 mm), both differing from soybean monoculture (3.15 mm), while winter crops showed significant differences only between sorghum (3.96 mm) and pigeon pea (3.25 mm). Two processes were identified in the soil under summer crop sequences. The first process was observed in PC1 (spore abundance, total glomalin, easily extractable glomalin, pH, P, and Mg2+) and was related to AMF; the second process occurred in PC2 (aggregate mean weight diameter, soil aggregate stability index, K+, and organic matter) and was related to soil aggregation. The nine‐year no‐tillage system under the same crop rotation adoption influenced AMF abundance in the soil, especially with corn cultivation in the summer crop sequence, which promoted an increased total external mycelium length and number of spores of AMF. In addition, it favored an increased soil organic matter content, which is directly related to the formation and stability of soil aggregates in these managements.  相似文献   
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Journal of Crop Science and Biotechnology - During cultivation, environmental factors can cause changes in the metabolism of Curcuma longa L. that limit its development. This study evaluated the...  相似文献   
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