Willows Used for Phytoremediation Increased Organic Contaminant Concentrations in Soil Surface

The Salix genus includes shrub species that are widely used in phytoremediation and various other phytotechnologies due to their advantageous characteristics, such as a high evapotranspiration (ET) rate, in particular when cultivated in short rotation intensive culture (SRIC). Observations made in past field studies suggest that ET and its impact on soil hydrology can also lead to increases in soil pollutant concentrations near shrubs. To investigate this, sections of a mature willow plantation (seven years old) were cut to eliminate transpiration (Cut treatment). Soil concentrations of polychlorinated biphenyls (PCBs), aliphatic compounds C10–C50, polycyclic aromatic hydrocarbons (PAHs) and five trace elements (Cd, Cr, Cu, Ni and Zn) were compared between the Cut and the uncut plots (Salix miyabeana ‘SX61’). Over 24 months, the results clearly show that removal of the willow shrubs limited the contaminants’ increase in the soil surface, as observed for C10–C50 and of 10 PAHs under the Salix treatment. This finding strongly reinforces a hypothesis that SRIC of willows may facilitate the migration of contaminants towards their roots, thus increasing their concentration in the surrounding soil. Such a “pumping effect” in a high-density willow crop is a prominent characteristic specific to field studies that can lead to counterintuitive results. Although apparent increases of contaminant concentrations contradict the purification benefits usually pursued in phytoremediation, the possibility of active phytoextraction and rhizodegradation is not excluded. Moreover, increases of pollutant concentrations under shrubs following migration suggest that decreases would consequently occur at the source points. Some reflections on interpreting field work results are provided.

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Calving Ice Walls

Annals of Glaciology ◽

10.3189/s0260305500006984 ◽

1989 ◽

Vol 12 ◽

pp. 74-80 ◽

Cited By ~ 4

Author(s):

T. Hughes

Keyword(s):

Shear Bands ◽

Ice Sheets ◽

Field Work ◽

Field Studies ◽

Line Field ◽

Dry Land ◽

Water Trough ◽

Ablation Mechanism ◽

Shear Rupture ◽

Made In

Calving ice walls are an important ablation mechanism for deglaciation of calving bays occupied by temperate tide-water glaciers and polar marine ice sheets. Dangers inherent in calving bays have precluded detailed field studies of these calving ice walls. However, calving ice walls also exist in sub-polar glaciers terminating on dry land, and an opportunity for detailed field work was afforded by the 12 August 1970 volcanic eruption on Deception Island (63.0°S, 60.6°W), where thawing of a surface blanket of ice-cemented ash produced solifluction ramps that made parts of the ice wall accessible. Measurements made in a melt-water trough incised into the ice wall, and in four tunnels cut into the ice wall, revealed numerous shear bands that rose almost vertically and curved forward. Shear offset increased upward and was greatest in shear bands that intersected the tips of ring-fault crevasses on the up-slope side of the ice wall. Near the base of the ice wall, other shear bands, possibly related to the slip-line field, intersected the ice wall at about 45°. Ice slabs separated by ring faults calved straight down as a result of shear rupture along these two sets of shear bands. Calving dynamics were analyzed and generalized for ice walls grounded in water.

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Calving Ice Walls

Annals of Glaciology ◽

10.1017/s0260305500006984 ◽

1989 ◽

Vol 12 ◽

pp. 74-80 ◽

Cited By ~ 19

Author(s):

T. Hughes

Keyword(s):

Shear Bands ◽

Ice Sheets ◽

Field Work ◽

Field Studies ◽

Line Field ◽

Dry Land ◽

Water Trough ◽

Ablation Mechanism ◽

Shear Rupture ◽

Made In

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Anion movement in a soil under pasture

Soil Research ◽

10.1071/sr9810299 ◽

1981 ◽

Vol 19 (3) ◽

pp. 299 ◽

Cited By ~ 28

Author(s):

DR Scotter ◽

P Kanchanasut

Keyword(s):

Hydraulic Conductivity ◽

Soil Surface ◽

Field Studies ◽

Phosphate Solution ◽

Biological Factors ◽

Matric Potential ◽

General Terms ◽

Fracture Planes ◽

Preferential Pathways ◽

Made In

Laboratory and field studies of anion movement in soils were made. In the laboratory the movement of a solution containing chloride and phosphate through saturated field cores (143 mm in diameter and 170 mm long) was studied. Both the anions appeared in the effluent almost immediately after application to the soil surface. Dye studies showed the movement was highly preferential, occurring mainly through biogenic macropores such as root and worm channels. Unsaturated solute flow was also studied in the laboratory. When the matric potential in these field cores was reduced from zero to -2.0 J/kg (-20 mb), the volumetric water content decreased from 0.56 to 0.53, while the hydraulic conductivity decreased two orders of magnitude. The flow of surface-applied bromide and dye in the slightly unsaturated soil was much less preferential than in the saturated soil, a finding that agrees in general terms with [he predictions of theory previously published. In the field, the flow of a surface-applied chloride and phosphate solution to a mole drain (at 0.4 m depth) was also highly preferential. In one experiment the concentration of both chloride and phosphate in the mole effluent exceeded 0.8 of that in the applied solution within 5 min of its application to the soil surface, when only 20 mm of solution had infiltrated. Dye studies again showed root and worm channels, sometimes in association with incipient fracture planes, were the preferential pathways. This indicates the importance of biological factors in maintaining hydraulic conductivity and mole drain performance.

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The Ancient Cart-tracks of Malta

Antiquity ◽

10.1017/s0003598x00025266 ◽

1954 ◽

Vol 28 (110) ◽

pp. 91-98 ◽

Cited By ~ 5

Author(s):

H. S. Gracie

Keyword(s):

Agricultural Soil ◽

Field Work ◽

Present Writer ◽

Small Scale ◽

Far North ◽

South Eastern ◽

Close Proximity ◽

Made In

The barren hill-tops of Malta are scored in many places by ancient ruts cut deeply into the rock. They can be seen also on the slopes and on the lower plains, but less frequently because these areas are normally under agricultural soil. They always occur in pairs from 52 to 58 inches apart and were quite clearly used by vehicles. They have been discussed in print for 300 years but no agreement has been reached on how, when or why they were made or what vehicles used them. In fact, there are as many theories as there are authors. Of these writers only Captain E. G. Fenton and Professor Sir T. Zammit appear to have done any serious field work, and none has published a map. The present writer, therefore, decided to attempt the laborious task of plotting them, making such other observations and measurements as he could. Zammit, in the paper cited, reproduced some excellent photographs from both the ground and the air, to which the reader is referred.Time did not permit an examination of the whole island and few observations were made in the low-lying south-eastern part. A fairly intensive survey was made of the high ground as far north as the Baida Ridge, which joins the northern shores of Ghain Tuffieha Bay and St. Paul’s Bay. Two portions of the map are reproduced here. Where there are a number of parallel tracks in close proximity they are shown on the map as one on account of the necessarily small scale used. The gaps in the routes are mainly due to cultivated patches, and no attempt has been made to bridge them by conjecture.

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Geographical vocabulary of the Shilan dialect of the Erzya-Mordovian language

Finno-Ugric World ◽

10.15507/2076-2577.012.2020.04.358-367 ◽

2020 ◽

Vol 12 (4) ◽

pp. 358-367

Author(s):

Nikolai V. Belenov

Keyword(s):

Original Composition ◽

Research Methods ◽

Field Studies ◽

The Other ◽

Volga Region ◽

The One ◽

Xix Century ◽

First Time ◽

Source Materials ◽

Made In

Introduction. The article presents the results of research of the geographical vocabulary of the Shilan dialect, one of the Erzya-Mordovian dialects of the Samara region, common among Erzya population of Shilan village in Krasnoyarsk region. The dialect belongs to rare Mordovian dialects of the Samara Volga region that were formed in the region since the middle of the XIX century, and therefore its research is of extra interest. Materials and Methods. The research methods are determined by the purpose and objectives of the study. The analysis of the geographical vocabulary of the Shilan dialect is carried out with the involvement of relevant items made in other Mordovian dialects of Samara region, adjacent territories of neighboring regions, as well as other territories of settlement of the Mordovians. Data on geographical vocabulary of the dialect introduced into research for the first time. The main source materials for the article is based on field studies in Silane village during the field seasons in 2017 and 2020, as well as in other Erzya-Mordovian and Moksha-Mordovian villages of Samara region and adjacent territories in 2015 – 2020. Results and Discussion. The study showed that the geographical vocabulary of the Shilan dialect of the Erzya-Mordovian language is significantly different from the corresponding lexical clusters in other dialects of the Mordovian region, which can be explained by natural geographical conditions surrounding Shilan village and the original composition of this lexical cluster of Erzya immigrants who founded this village. Conclusion. The analysis of the geographical vocabulary of the Shilan dialect allowed, on the one hand, to identify specific features of this cluster that distinguish it from the corresponding materials of other Mordovian dialects of the region, and, on the other hand, to identify common isoglosses between it and a number of the Erzya-Mordovian dialects of the Samara Volga region.

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Archaeology in New China

Antiquity ◽

10.1017/s0003598x00029926 ◽

1963 ◽

Vol 37 (147) ◽

pp. 176-184 ◽

Cited By ~ 3

Author(s):

Hsia Nai

Keyword(s):

Field Work ◽

Archaeological Research ◽

Historical Science ◽

Considerable Success ◽

Large Numbers ◽

History Of ◽

Ancient Monuments ◽

Economic Construction ◽

Abundant Data ◽

Made In

Archaeology as a branch of historical science has made new headway in the thirteen years since the founding of the Chinese People's Republic. The scale of its work has expanded and methods of research have been improved. Large numbers of young archaeological workers have been trained. In the course of the nation's gigantic economic construction, remains of ancient settlements and tombs have been uncovered in many places, yielding numerous important relics which have provided abundant data for archaeological research. Throughout the country, hosts of archaeological workers from research institutes, universities, museums and institutions for the preservation of ancient monuments are carrying out both field work and academic study and have already attained considerable success in their efforts to explore the history of ancient China on the basis of archaeological finds. All this has given further impetus to the advance of Chinese archaeology.Archaeological finds made in New China are so rich that the present article can attempt to discuss only some of the most important problems.

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Laboratory and field studies on the degradation of fipronil in a soil

Soil Research ◽

10.1071/sr02018 ◽

2002 ◽

Vol 40 (7) ◽

pp. 1095 ◽

Cited By ~ 40

Author(s):

Guang-Guo Ying ◽

Rai Kookana

Keyword(s):

Soil Moisture ◽

Half Life ◽

Soil Moisture Content ◽

Soil Surface ◽

Field Studies ◽

Transformation Product ◽

Laboratory Studies ◽

The Third ◽

High Soil Moisture ◽

Sulfone Derivatives

Degradation of a new insecticide/termiticide, fipronil, in a soil was studied in the laboratory and field. Three metabolites of fipronil (desulfinyl, sulfide, and sulfone derivatives) were identified from soils after treatment. Laboratory studies showed that soil moisture content had a great effect on the degradation rate of fipronil and products formed. High soil moisture contents (>50%) favored the formation of a sulfide derivative of fipronil by reduction, whereas low soil moisture (<50%) and well-aerated conditions favored the formation of fipronil sulfone by oxidation. Microorganisms in soil accelerated the degradation of fipronil to sulfide and sulfone derivatives. The third transformation product, a desulfinyl derivative, was formed by photodecomposition of fipronil in water and on the soil surface under sunlight. The desulfinyl derivative degraded rapidly in field soils with a half-life of 41–55 days compared with an average half-life of 132 days for fipronil. The half-life of the 'total toxic component' (fipronil and its metabolites) in field soil was 188 days on average.

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Ethylene: A Witchweed Seed Germination Stimulant

Weed Science ◽

10.1017/s0043174500062822 ◽

1975 ◽

Vol 23 (5) ◽

pp. 433-436 ◽

Cited By ~ 88

Author(s):

Robert E. Eplee

Keyword(s):

United States ◽

Seed Germination ◽

Clay Soil ◽

Soil Surface ◽

Field Studies ◽

The United States ◽

Major Contributor ◽

Single Treatment ◽

Striga Asiatica ◽

Heavy Clay

Ethylene gas (C2H4) was found to stimulate the germination of witchweed [Striga asiatica(L.) O. Kuntze] seeds. Ethylene diffuses greater than 120 cm horizontally from point of injection and more than 90 cm below the soil surface. Rates of 0.42 kg/ha induced germination of witchweed seeds in sandy soil; but 1.1 kg/ha is required on a heavy clay soil. Witchweed seeds respond to ethylene after a period of preconditioning that is necessary to break dormancy. Under field conditions in the Carolinas, maximum response of seeds to ethylene occurs between late April and late July. Field studies indicate a 90% reduction in viable witchweed seeds occurs where a single treatment with ethylene has been applied. The use of ethylene appears now to be a major contributor toward the eventual eradication of witchweed from the United States.

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The Collapse of Thermal Contraction

The Rejection of Continental Drift ◽

10.1093/oso/9780195117325.003.0008 ◽

1999 ◽

Author(s):

Naomi Oreskes

Keyword(s):

Field Work ◽

Field Studies ◽

Lower Limbs ◽

Swiss Alps ◽

Late Nineteenth Century ◽

Thermal Contraction ◽

Thrust Faults ◽

The Alps ◽

Academy Of Sciences ◽

Contraction Theory

In 1901, Karl Zittel, president of the Bavarian Royal Academy of Sciences, declared that “Suess has secured almost general recognition for the contraction theory” of mountain-building. This was wishful thinking. Suess’s Das Antlitz der Erde was indeed an influential work, but by the time Suess finished the final volume (1904), the thermal contraction theory was under serious attack. Problems were evident from three different but equally important quarters. The most obvious problem for contraction theory arose from field studies of mountains themselves. As early as the 1840s, it had been recognized that the Swiss Alps contained large slabs of rock that appeared to have been transported laterally over enormous distances. These slabs consisted of nearly flat-lying rocks that might be construed as undisplaced, except that they lay on top of younger rocks. In the late nineteenth century, several prominent geologists, most notably Albert Heim (1849 –1937), undertook extensive field work in the Alps to attempt to resolve their structure. Heim’s detailed field work, beautiful maps, and elegant prose convinced geological colleagues that the Alpine strata had been displaced horizontally over enormous distances. In some cases, the rocks had been accordioned so tightly that layers that previously extended horizontally for hundreds of kilometers were now reduced to distances of a few kilometers. But in even more startling cases, the rocks were scarcely folded at all, as if huge slabs of rocks had been simply lifted up from one area of the crust and laid down in another. Heim interpreted the slabs of displaced rock in his own Glarus district as a huge double fold with missing lower limbs, but in 1884 the French geologist Marcel Bertrand (1847–1907) argued that these displacements were not folds but faults. Large segments of the Alps were the result of huge faults that had thrust strata from south to north, over and on top of younger rocks. August Rothpletz (1853–1918), an Austrian geologist, realized that the Alpine thrust faults were similar to those that had been earlier described by the Rogers brothers in the Appalachians. By the late 1880s, thrust faults had been mapped in detail in North America, Scotland, and Scandinavia.

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Gene Transfer of Multiple Flowers and Pubescent Leaf from Capsicum chinense into Capsicum annuum Backgrounds

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.115.3.499 ◽

1990 ◽

Vol 115 (3) ◽

pp. 499-502 ◽

Cited By ~ 4

Author(s):

D.M. Shuh ◽

James F. Fontenot

Keyword(s):

Capsicum Annuum ◽

Female Parent ◽

Field Studies ◽

Segregation Ratio ◽

Gene Model ◽

Leaf Pubescence ◽

Segregation Ratios ◽

Selective Elimination ◽

Dominant Genes ◽

Made In

The inheritance of multiple flowers and leaf pubescence resulting from the crosses between accessions from pepper species Capsicum annuum L. and C. chinense Jacq. was examined. Hand cross- and self-pollinations were made in a glass greenhouse. Only eight normal F1 plants were obtained from crosses between the two species when C. annuum L. was the female parent. F2 and backcross generations obtained from the F, and the two parents were grown in the field. Two field studies indicated that multiple flowers and leaf pubescence were controlled by dominant genes. A three-gene model leading to an F2 segregation ratio of 45:9:10 and a two-gene model leading to an F2 segregation ratio of 13:3 were suggested for the inheritance of multiple flowers and leaf pubescence, respectively. Epistasis was evoked in the interpretation of the data. No linkage was found between the two characters. The inconsistencies between F2 and backcross data might be due to selective elimination of genes from one or the other parent in an Interspecific hybridization. Segregation ratios from intraspecific crosses for leaf pubescence supported a two-gene model and gave an F2 ratio of 13 pubescent leaf : 3 glabrous leaf progeny.

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