Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil ...Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources.Phytoremediation,being more cost-effective and fewer side effects than physical and chemical approaches,has gained increasing popularity in both academic and practical circles.More than 400 plant species have been identified to have potential for soil and water remediation.Among them,Thlaspi,Brassica,Sedum alfredii H.,and Arabidopsis species have been mostly studied.It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come.This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources.展开更多
The objective of this work is to produce statistics that are going to show changes occurred in Brazil＇s ecosystems and these statistics are going to join the SEEA （Environmental-Economic Accounts System）. It is bas...The objective of this work is to produce statistics that are going to show changes occurred in Brazil＇s ecosystems and these statistics are going to join the SEEA （Environmental-Economic Accounts System）. It is based by a SEEA＇s methodology, diffused by UN （United Nations）, which aims an approach between economic and environmental statistics, producing international comparability and conceptual uniformity to evaluate change process in land cover and land use that occurs in several countries. It is necessary to verifying the suitability of methodological procedures to Brazilian reality and the access to all information and files needed. The first step was analysing MODIS （Moderate Resolution Imaging Spectroradiometer） as orbital instrument on the purposed classification method. The choice of this sensor was made because of the product＇s quality and its capacity to generate images of a large area, though the challenge is to identify accurate Land usage＇s categories in images with a spatial resolution of approximately 250 m. After the final classification, the next step is to make a quantification and comparison of data from these different years using a 1 km2 grids, as proposed in an already used methodology by the European Environment Agency. This procedure will allow evaluate and identify the process of changing in each grid of the land cover and land use, and provide historical series of the chosen years.展开更多
Biochars are, amongst other available amendment materials, considered as an attractive tool in agriculture for carbon sequestration and improvement of soil functions. The latter is widely discussed as a consequence of...Biochars are, amongst other available amendment materials, considered as an attractive tool in agriculture for carbon sequestration and improvement of soil functions. The latter is widely discussed as a consequence of improved physical quality of the amended soil.However, the mechanisms for this improvement are still poorly understood. This study investigated the effect of woodchip biochar amendment on micro-structural development, micro-and macro-structural stability, and resilience of two differently textured soils,fine sand(FS) and sandy loam(SL). Test substrates were prepared by adding 50 or 100 g kg^(-1) biochar to FS or SL. Total porosity and plant available water were significantly increased in both soils. Moreover, compressive strength of the aggregates was significantly decreased when biochar amount was doubled. Mechanical resilience of the aggregates at both micro-and macro-scale was improved in the biochar-amended soils, impacting the cohesion and compressive behavior. A combination of these effects will result in an improved pore structure and aeration. Consequently, the physicochemical environment for plants and microbes is improved. Furthermore, the improved stability properties will result in better capacity of the biochar-amended soil to recover from the myriad of mechanical stresses imposed under arable systems, including vehicle traffic, to the weight of overburden soil. However, it was noted that doubling the amendment rate did not in any case offer any remarkable additional improvement in these properties, suggesting a further need to investigate the optimal amendment rate.展开更多
Anti-adhesion is a common phenomenon in living organisms, which is the evolution results to adapt their living surroundings. From the perspective of surface type, there are two typical anti-adhesion mechanisms： micro...Anti-adhesion is a common phenomenon in living organisms, which is the evolution results to adapt their living surroundings. From the perspective of surface type, there are two typical anti-adhesion mechanisms： micro- and nano- surface structures and liquid-covered surface. Many living organisms possess one or two of these anti-adhesion surfac- es in order to achieve superior anti-adhesion, for example, soil animals like mole cricket and earthworm [1]. Carnivo- rous pitcher plant Nepenthes can capture and digest insects to meet the fundamental nutrients needs. When the insects crawl on its slippery peristome, they could easy-sliding into the picher, known as ＂aquaplaning＂. Wong et al. [2] at Harvard University has designed and fabricated slippery surface mimicking this slippery mechanism in Nepenthes, the results of which was published in Nature. However, questions remain about the mechanism underlying its func- tion, especially for the liquid film formation mechanism.展开更多
基金Project supported by the Higher Education Commission,Government of Pakistan for the faculty training under the R & D Project"Strengthening Department of Soil Science and Soil and Water Conservation" at the University of Florida,USA,a grant from the St. Lucie River Water Initiative (SFWMD contract No. OT060162),USA,in partthe Program for Changjiang Scholars and Innovative Research Team in University (No.IRT0536),China
文摘Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources.Phytoremediation,being more cost-effective and fewer side effects than physical and chemical approaches,has gained increasing popularity in both academic and practical circles.More than 400 plant species have been identified to have potential for soil and water remediation.Among them,Thlaspi,Brassica,Sedum alfredii H.,and Arabidopsis species have been mostly studied.It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come.This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources.
文摘The objective of this work is to produce statistics that are going to show changes occurred in Brazil＇s ecosystems and these statistics are going to join the SEEA （Environmental-Economic Accounts System）. It is based by a SEEA＇s methodology, diffused by UN （United Nations）, which aims an approach between economic and environmental statistics, producing international comparability and conceptual uniformity to evaluate change process in land cover and land use that occurs in several countries. It is necessary to verifying the suitability of methodological procedures to Brazilian reality and the access to all information and files needed. The first step was analysing MODIS （Moderate Resolution Imaging Spectroradiometer） as orbital instrument on the purposed classification method. The choice of this sensor was made because of the product＇s quality and its capacity to generate images of a large area, though the challenge is to identify accurate Land usage＇s categories in images with a spatial resolution of approximately 250 m. After the final classification, the next step is to make a quantification and comparison of data from these different years using a 1 km2 grids, as proposed in an already used methodology by the European Environment Agency. This procedure will allow evaluate and identify the process of changing in each grid of the land cover and land use, and provide historical series of the chosen years.
基金the George Foster Research Fellowship provided by Alexander yon Humboldt Fellowship of Germany.
文摘Biochars are, amongst other available amendment materials, considered as an attractive tool in agriculture for carbon sequestration and improvement of soil functions. The latter is widely discussed as a consequence of improved physical quality of the amended soil.However, the mechanisms for this improvement are still poorly understood. This study investigated the effect of woodchip biochar amendment on micro-structural development, micro-and macro-structural stability, and resilience of two differently textured soils,fine sand(FS) and sandy loam(SL). Test substrates were prepared by adding 50 or 100 g kg^(-1) biochar to FS or SL. Total porosity and plant available water were significantly increased in both soils. Moreover, compressive strength of the aggregates was significantly decreased when biochar amount was doubled. Mechanical resilience of the aggregates at both micro-and macro-scale was improved in the biochar-amended soils, impacting the cohesion and compressive behavior. A combination of these effects will result in an improved pore structure and aeration. Consequently, the physicochemical environment for plants and microbes is improved. Furthermore, the improved stability properties will result in better capacity of the biochar-amended soil to recover from the myriad of mechanical stresses imposed under arable systems, including vehicle traffic, to the weight of overburden soil. However, it was noted that doubling the amendment rate did not in any case offer any remarkable additional improvement in these properties, suggesting a further need to investigate the optimal amendment rate.
文摘Anti-adhesion is a common phenomenon in living organisms, which is the evolution results to adapt their living surroundings. From the perspective of surface type, there are two typical anti-adhesion mechanisms： micro- and nano- surface structures and liquid-covered surface. Many living organisms possess one or two of these anti-adhesion surfac- es in order to achieve superior anti-adhesion, for example, soil animals like mole cricket and earthworm [1]. Carnivo- rous pitcher plant Nepenthes can capture and digest insects to meet the fundamental nutrients needs. When the insects crawl on its slippery peristome, they could easy-sliding into the picher, known as ＂aquaplaning＂. Wong et al. [2] at Harvard University has designed and fabricated slippery surface mimicking this slippery mechanism in Nepenthes, the results of which was published in Nature. However, questions remain about the mechanism underlying its func- tion, especially for the liquid film formation mechanism.
