Early-summer pheromone biology of Galerucella calmariensis and relationship to dispersal and colonization

2008 ◽  
Vol 46 (3) ◽  
pp. 409-416 ◽  
Author(s):  
Robert J. Bartelt ◽  
Allard A. Cossé ◽  
Bruce W. Zilkowski ◽  
Robert N. Wiedenmann ◽  
S. Raghu
EDIS ◽  
2019 ◽  
Vol 2019 (5) ◽  
pp. 3
Author(s):  
Ramdas Kanissery ◽  
Biwek Gairhe ◽  
Brent Sellers ◽  
Steve Futch

In Florida, clustered pellitory is becoming a troublesome weed for citrus, especially from the winter through early summer. Inadequate management of this weed can result in its heavy infestation in tree rows and can interrupt the spray pattern of low-volume drip irrigation systems. This new 3-page publication of the UF/IFAS Horticultural Sciences Department will assist Florida citrus growers with proper identification of clustered pellitory and with adoption of adequate and timely strategies to manage this weed in their groves. Written by Ramdas Kanissery, Biwek Gairhe, Brent Sellers, and Steve Futch. https://edis.ifas.ufl.edu/hs1341


2019 ◽  
Vol 16 (1) ◽  
pp. 25-35 ◽  
Author(s):  
N.A. Komaromi ◽  
A.V. Putchkov ◽  
V.Yu. Nazarenko

A total of 54 species in 35 genera of Curculionidae are registered in the urbocenoses of Kharkiv city. Only three species, Exomias pellucidus, Otiorhynchus raucus and Ot. ovatus, are recorded as dominants. Some other species (Urometopus nemorum, Sciaphobus squalidus and Glocianus punctiger) are sporadically noted in some sites as subdominants. The total number of species turned out to be higher in the herpetobios of plantings at periphery (31), slightly lower in private farmlands of the city (21), parks and plantings of the center (17 each), but minimal in suburban forests (11 species). The highest quantity of specimens were observed for the plantations of the center and margins of city: nevertheless, minimal quantity of specimens was registered at parks and woods. The maximum number of species (including all cenoses) was recorded from the end of April to first decade of May (28 species). From May to the end of June 15–18 species were registered. Ten species were recorded at July, and only six species at August. A slight rise was noted from the end of August to mid-September (11 species). In biotopes where Exomias pellucidus appeared to be the monodominant, the seasonal dynamic density of weevils reached a peak at late May or early June, but the significant decline was observed from early June to July. At the sites with several dominants, two or three peaks were registered: at spring (May) and at mid-summer (end of June or beginning of July). Furthermore, the number of weevils decreased gradually, but some species of Curculionidae were rather abundant even from the end of summer to September–October. The spring increase is reasoned by high density of species in the genus Otiorhynchus; the peak in early summer (maximum) is caused by the increased activity of majority of dominant species; the autumn peak is also caused by the high number of species of the genus Otiorhynchus. The level of sex index (by the example of E. pellucidus) differed significantly at all plots. It was higher for the plantations at the periphery of the city (0.70), and it was minimal at private farmlands (0.20). Relative conjugacy of sex index and dynamic density were not observed: the maximum abundances of quantity of Curculionidae were recorded 20–30 days earlier than the maximal numbers of the sex index.


2020 ◽  
Vol 11 (3) ◽  
pp. 215-221
Author(s):  
M. Ramadan ◽  
M. Abd El-Wahed ◽  
Enas Bardisi

1998 ◽  
Vol 37 (2) ◽  
pp. 145-152 ◽  
Author(s):  
A. E. Nienhüser ◽  
P. Braches

Refilling of the Kerspe-Talsperre reservoir after restoration of the dam caused severe problems in water quality and supply due to a long-lasting ice-cover period and minimal precipitation. Unusually short spring overturn, high algal mass in spring and certainly the overflooding of the sediment, which had not been removed, caused a tremendous oxygen deficit in early summer. The whole hypolimnion turned anoxic and even in the metalimnion oxygen declined to a minimum. Manganese and iron reached high concentrations. Despite the poor water quality, raw water was urgently needed for the water supply and was pumped from the epilimnion during the clear water phase and in July when algal biomass was low. In the middle of August holomixis was induced artificially in order to improve water quality. The decline in algal production during and after artificial mixing was probably caused by light limitation of the algae.


2015 ◽  
Vol 8 (4) ◽  
pp. 3235-3292 ◽  
Author(s):  
A. L. Atchley ◽  
S. L. Painter ◽  
D. R. Harp ◽  
E. T. Coon ◽  
C. J. Wilson ◽  
...  

Abstract. Climate change is profoundly transforming the carbon-rich Arctic tundra landscape, potentially moving it from a carbon sink to a carbon source by increasing the thickness of soil that thaws on a seasonal basis. However, the modeling capability and precise parameterizations of the physical characteristics needed to estimate projected active layer thickness (ALT) are limited in Earth System Models (ESMs). In particular, discrepancies in spatial scale between field measurements and Earth System Models challenge validation and parameterization of hydrothermal models. A recently developed surface/subsurface model for permafrost thermal hydrology, the Advanced Terrestrial Simulator (ATS), is used in combination with field measurements to calibrate and identify fine scale controls of ALT in ice wedge polygon tundra in Barrow, Alaska. An iterative model refinement procedure that cycles between borehole temperature and snow cover measurements and simulations functions to evaluate and parameterize different model processes necessary to simulate freeze/thaw processes and ALT formation. After model refinement and calibration, reasonable matches between simulated and measured soil temperatures are obtained, with the largest errors occurring during early summer above ice wedges (e.g. troughs). The results suggest that properly constructed and calibrated one-dimensional thermal hydrology models have the potential to provide reasonable representation of the subsurface thermal response and can be used to infer model input parameters and process representations. The models for soil thermal conductivity and snow distribution were found to be the most sensitive process representations. However, information on lateral flow and snowpack evolution might be needed to constrain model representations of surface hydrology and snow depth.


2020 ◽  
pp. 1-11
Author(s):  
Guanghua Hao ◽  
Roberta Pirazzini ◽  
Qinghua Yang ◽  
Zhongxiang Tian ◽  
Changwei Liu

Abstract The surface spectral albedo was measured over coastal landfast sea ice in Prydz Bay (off Zhongshan Station), East Antarctica from 5 October to 26 November of 2016. The mean albedo decreased from late-spring to early-summer, mainly responding to the change in surface conditions from dry (phase I) to wet (phase II). The evolution of the albedo was strongly influenced by the surface conditions, with alternation of frequent snowfall events and katabatic wind that induce snow blowing at the surface. The two phases and day-to-day albedo variability were more pronounced in the near-infrared albedo wavelengths than in the visible ones, as the near-infrared photons are more sensitive to snow metamorphism, and to changes in the uppermost millimeters and water content of the surface. The albedo diurnal cycle during clear sky conditions was asymmetric with respect to noon, decreasing from morning to evening over full and patchy snow cover, and decreasing more rapidly in the morning over bare ice. We conclude that snow and ice metamorphism and surface melting dominated over the solar elevation angle dependency in shaping the albedo evolution. However, we realize that more detailed surface observations are needed to clarify and quantify the role of the various surface processes.


Author(s):  
Luyu Chang ◽  
Fangfang He ◽  
Xuexi Tie ◽  
Jianming Xu ◽  
Wei Gao
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