Intra-seasonal activity of ground dwelling spiders following six years of tillage, fertiliser and weeding treatments in an agricultural field in northern Zimbabwe

2020 ◽  
Vol 37 (5) ◽  
pp. 343-350
Author(s):  
Nilton Mashavakure ◽  
Delight Vhembo ◽  
Arnold B Mashingaidze ◽  
Edson Gandiwa
Keyword(s):  
Seasonal Activity ◽  
Agricultural Field

Land, People and Power in Early Medieval Wales: The cantref of Cemais in comparative perspective

2020 ◽  
Author(s):  
Rhiannon Comeau
Keyword(s):  
Comparative Analysis ◽  
Urban Society ◽  
Comparative Perspective ◽  
Seasonal Activity ◽  
Early Medieval ◽  
Habitual Activity ◽  
Activity Cycles

A study of seasonal activity cycles in a pre-urban society, examined through the lens of an early medieval Welsh case study. It examines how these cycles shaped patterns of power and habitual activity, defining spaces and structuring lives. Its multidisciplinary, comparative analysis identifies focal zones and challenges commonly applied interpretations.

Dissolved Phosphorus Losses in Tile Drainage under Subirrigation

2006 ◽  
Vol 41 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Nicolas Stämpfli ◽  
Chandra A. Madramootoo
Keyword(s):  
Water Table ◽  
Residual Effect ◽  
Surface Water Quality ◽  
Soil Surface ◽  
Quality Standard ◽  
Tile Drainage ◽  
Agricultural Field ◽  
Shallow Water Table ◽  
Dissolved Phosphorus ◽  
Water Table Control

Abstract Recent studies have shown subirrigation (SI) to be effective in reducing nitrate losses from agricultural tile drainage systems. A field study was conducted from 2001 to 2002 in southwestern Québec to evaluate the effect of SI on total dissolved phosphorus (TDP) losses in tile drainage. In an agricultural field with drains installed at a 1-m depth, a SI system with a design water table depth (WTD) of 0.6 m below the soil surface was compared with conventional free drainage (FD). Subirrigation increased drainage outflow volumes in the autumn, when drains were opened and water table control was interrupted for the winter in the SI plots. Outflows were otherwise similar for both treatments. Throughout the study, the TDP concentrations in tile drainage were significantly higher with SI than with FD for seven out of 17 of the sampling dates for which data could be analyzed statistically, and they were never found to be lower for plots under SI than for plots under FD. Of the seven dates for which the increase was significant, six fell in the period during which water table control was not implemented (27 September 2001 to 24 June 2002). Hence, it appears that SI tended to increase TDP concentrations compared with FD, and that it also had a residual effect between growing seasons. Almost one-third of all samples from the plots under SI exceeded Québec's surface water quality standard (0.03 mg TDP L-1), whereas concentrations in plots under FD were all below the standard. Possible causes of the increase in TDP concentrations in tile drainage with SI are high TDP concentrations found in the well water used for SI and a higher P solubility caused by the shallow water table.

ESTIMATING THE NITROGEN LOAD TO GROUNDWATER BENEATH AN AGRICULTURAL FIELD

2018 ◽  
Author(s):  
Madeline B. Gotkowitz ◽  
◽  
Jacob J. Krause ◽  
Michael Cardiff ◽  
Laura Schachter
Keyword(s):  
Agricultural Field

scholarly journals Determination of seasonal activity of the sweetpotato whitefly (Homoptera: Aleyrodidae) and leafhoppers (Homoptera: Cicadellidae) by plastic cup traps on the Çukurova Plain, Turkey.

2010 ◽  
Vol 41 (No. 1) ◽  
pp. 8-13 ◽  
Author(s):  
K. Karut ◽  
C. Chu C ◽  
T.J. Henneberry ◽  
C. Kazak
Keyword(s):  
Bemisia Tabaci ◽  
Seasonal Activity ◽  
Sweetpotato Whitefly ◽  
Daily Minimum ◽  
Trap Catches

The flight activities of adult sweetpotato whitefly, Bemisia tabaci, and leafhoppers were monitored by plastic cup traps at Boğalı, Taşçı, Hacıali, Doğankent and Balcalı in the Çukurova Plain, Turkey, in 2001 and 2003. Activity of B. tabaci, expressed as numbers of adults caught in traps, was low from May to early July in both years. Numbers of B. tabaci caught at Tasçı were higher than at Boğalı from 10 July and 21 August in 2001. Its numbers were also higher at Doğankent than at Hacıali and Balcalı during August of 2003. The numbers of leafhopper adults caught fluctuated greatly in both years. Numbers remained low until late June, followed by gradual increases in July and August at Boğalı and Taşçı in 2001. In contrast, numbers of adults caught were higher at Hacıali, Doğankent and Balcalı from May through July in 2003, followed by lower catches during the remainder of the season. Daily minimum temperatures in July and August were positively correlated with higher trap catches of both B. tabaci and leafhoppers.

Seasonal Activity of Haemaphysalis longicornis (Acari: Ixodidae) in Southern New York State

2020 ◽  
Author(s):  
Nicholas P Piedmonte ◽  
Vanessa C Vinci ◽  
Thomas J Daniels ◽  
Bryon P Backenson ◽  
Richard C Falco
Keyword(s):  
United States ◽  
New York ◽  
Activity Patterns ◽  
New York State ◽  
The United States ◽  
Haemaphysalis Longicornis ◽  
Seasonal Activity ◽  
Eastern Asia ◽  
Short Life ◽  
Human Bite

Abstract The Asian longhorned tick, Haemaphysalis longicornis Neumann, is a species native to eastern Asia that has recently been discovered in the United States. In its native range, H. longicornis transmits pathogens that cause disease in humans and livestock. It is currently unknown whether H. longicornis will act as a vector in the United States. Understanding its seasonal activity patterns will be important in identifying which times of the year represent greatest potential risk to humans and livestock should this species become a threat to animal or public health. A study site was established in Yonkers, NY near the residence associated with the first reported human bite from H. longicornis in the United States. Ticks were collected once each week from July 2018 to November 2019. Haemaphysalis longicornis larvae were most active from August to November, nymphs from April to July, and adult females from June to September. This pattern of activity suggests that H. longicornis is capable of completing a generation within a single year and matches the patterns observed in its other ranges in the northern hemisphere. The data presented here contribute to a growing database for H. longicornis phenology in the northeastern United States. Potential implications of the short life cycle for the tick’s vectorial capacity are discussed.

scholarly journals An analysis of the spatial association between deforestation and agricultural field sizes in the tropics and subtropics

PLoS ONE ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. e0209918 ◽  
Author(s):  
Doan K. D. Dang ◽  
Amy C. Patterson ◽  
Luis R. Carrasco
Keyword(s):  
Spatial Association ◽  
Agricultural Field ◽  
The Tropics

scholarly journals Identification of a juvenile-hormone signaling inhibitor via high-throughput screening of a chemical library

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Takumi Kayukawa ◽  
Kenjiro Furuta ◽  
Keisuke Nagamine ◽  
Tetsuro Shinoda ◽  
Kiyoaki Yonesu ◽  
...  
Keyword(s):  
Juvenile Hormone ◽  
Cell Line ◽  
Signaling Pathway ◽  
High Throughput ◽  
High Throughput Screening ◽  
Large Scale ◽  
Ex Vivo ◽  
Agricultural Field ◽  
Chemical Library ◽  
Field Development

Abstract Insecticide resistance has recently become a serious problem in the agricultural field. Development of insecticides with new mechanisms of action is essential to overcome this limitation. Juvenile hormone (JH) is an insect-specific hormone that plays key roles in maintaining the larval stage of insects. Hence, JH signaling pathway is considered a suitable target in the development of novel insecticides; however, only a few JH signaling inhibitors (JHSIs) have been reported, and no practical JHSIs have been developed. Here, we established a high-throughput screening (HTS) system for exploration of novel JHSIs using a Bombyx mori cell line (BmN_JF&AR cells) and carried out a large-scale screening in this cell line using a chemical library. The four-step HTS yielded 69 compounds as candidate JHSIs. Topical application of JHSI48 to B. mori larvae caused precocious metamorphosis. In ex vivo culture of the epidermis, JHSI48 suppressed the expression of the Krüppel homolog 1 gene, which is directly activated by JH-liganded receptor. Moreover, JHSI48 caused a parallel rightward shift in the JH response curve, suggesting that JHSI48 possesses a competitive antagonist-like activity. Thus, large-scale HTS using chemical libraries may have applications in development of future insecticides targeting the JH signaling pathway.

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