Fire can weaken or trigger functional responses of trees to flooding in wetland forest patches

The present study investigated whether the flushing distance, the territorial use and the stress hormone physiology of the capercaillie (Tetrao urogallus) were influenced in the winter by the presence of a large number of people engaged in sporting activities. In most cases flushing distances were greater, and higher concentrations of stress hormone were found in the blood serum, in areas having a high intensity of sporting activities than in forest stands relatively undisturbed by tourists. During the ski season capercaillie avoided forest patches within their home ranges where there was a high level of recreational activity. The results lead to the conclusion that intensive winter tourism can be a serious threat to the remaining capercaillie populations in middle Europe. It is recommended that the construction of new recreational facilities and new developments should be avoided in the most important habitats for capercaillie. The important habitats which today already lie in the immediate vicinity of areas intensively used by tourists could clearly receive enhanced status, according to each situation, either as tranquility areas for wildlife where entrance is forbidden or with regulations requiring winter tourists to stay on trails.

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Population Dynamics and Mutualism: Functional Responses of Benefits and Costs

The American Naturalist ◽

10.2307/3079075 ◽

2002 ◽

Vol 159 (3) ◽

pp. 231

Author(s):

Holland ◽

DeAngelis ◽

Bronstein

Keyword(s):

Population Dynamics ◽

Functional Responses ◽

Benefits And Costs

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Tyrosine kinase-dependent phosphatidylinositol turnover and functional responses in the FcεR1 signalling pathway

Biochemical and Biophysical Research Communications ◽

10.1016/0006-291x(91)91406-3 ◽

1991 ◽

Vol 179 (1) ◽

pp. 551-557 ◽

Cited By ~ 16

Author(s):

Grace G. Deanin ◽

A.Marina Martinez ◽

Janet R. Pfeiffer ◽

Mary E. Gardner ◽

Janet M. Oliver

Keyword(s):

Tyrosine Kinase ◽

Signalling Pathway ◽

Functional Responses ◽

Phosphatidylinositol Turnover

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Expression of P2X7purinoceptors on human lymphocytes and monocytes: evidence for nonfunctional P2X7receptors

AJP Cell Physiology ◽

10.1152/ajpcell.2000.279.4.c1189 ◽

2000 ◽

Vol 279 (4) ◽

pp. C1189-C1197 ◽

Cited By ~ 140

Author(s):

B. J. Gu ◽

W. Y. Zhang ◽

L. J. Bendall ◽

I. P. Chessell ◽

G. N. Buell ◽

...

Keyword(s):

B Lymphocytes ◽

Adhesion Molecule ◽

Human Lymphocytes ◽

Normal Subjects ◽

Cell Types ◽

Surface Expression ◽

Lymphocytic Leukemia ◽

Functional Responses ◽

Intracellular Expression ◽

Selective Channel

Lymphocytes from normal subjects and patients with B-chronic lymphocytic leukemia (B-CLL) show functional responses to extracellular ATP characteristic of the P2X7receptor (previously termed P2Z). These responses include opening of a cation-selective channel/pore that allows entry of the fluorescent dye ethidium and activation of a membrane metalloprotease that sheds the adhesion molecule L-selectin. The surface expression of P2X7receptors was measured in normal leucocytes, platelets, and B-CLL lymphocytes and correlated with their functional responses. Monocytes showed four- to fivefold greater expression of P2X7than B, T, and NK lymphocytes, whereas P2X7expression on neutrophils and platelets was weak. All cell types demonstrated abundant intracellular expression of this receptor. All 12 subjects with B-CLL expressed lymphocyte P2X7at about the same level as B lymphocytes from normal subjects. P2X7function, measured by ATP-induced uptake of ethidium, correlated closely with surface expression of this receptor in normal and B-CLL lymphocytes and monocytes ( n = 47, r = 0.70; P< 0.0001). However, in three patients the ATP-induced uptake of ethidium into the malignant B lymphocytes was low or absent. The lack of P2X7function in these B lymphocytes was confirmed by the failure of ATP to induce Ba2+uptake into their lymphocytes. This lack of function of the P2X7receptor resulted in a failure of ATP-induced shedding of L-selectin, an adhesion molecule that directs the recirculation of lymphocytes from blood into the lymph node.

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Spatial Analysis of the Drivers, Characteristics, and Effects of Forest Fragmentation

Sustainability ◽

10.3390/su13063246 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3246

Author(s):

Zoe Slattery ◽

Richard Fenner

Keyword(s):

Forest Fragmentation ◽

Forest Fires ◽

Geographical Information ◽

Agricultural Expansion ◽

Forest Patches ◽

Mato Grosso ◽

Remote Imaging ◽

Landscape Characteristics ◽

High Level

Building on the existing literature, this study examines whether specific drivers of forest fragmentation cause particular fragmentation characteristics, and how these characteristics can be linked to their effects on forest-dwelling species. This research uses Landsat remote imaging to examine the changing patterns of forests. It focuses on areas which have undergone a high level of a specific fragmentation driver, in particular either agricultural expansion or commodity-driven deforestation. Seven municipalities in the states of Rondônia and Mato Grosso in Brazil are selected as case study areas, as these states experienced a high level of commodity-driven deforestation and agricultural expansion respectively. Land cover maps of each municipality are created using the Geographical Information System software ArcGIS Spatial Analyst extension. The resulting categorical maps are input into Fragstats fragmentation software to calculate quantifiable fragmentation metrics for each municipality. To determine the effects that these characteristics are likely to cause, this study uses a literature review to determine how species traits affect their responses to forest fragmentation. Results indicate that, in areas that underwent agricultural expansion, the remaining forest patches became more complex in shape with longer edges and lost a large amount of core area. This negatively affects species which are either highly dispersive or specialist to core forest habitat. In areas that underwent commodity-driven deforestation, it was more likely that forest patches would become less aggregated and create disjunct core areas. This negatively affects smaller, sedentary animals which do not naturally travel long distances. This study is significant in that it links individual fragmentation drivers to their landscape characteristics, and in turn uses these to predict effects on species with particular traits. This information will prove useful for forest managers, particularly in the case study municipalities examined in this study, in deciding which species require further protection measures. The methodology could be applied to other drivers of forest fragmentation such as forest fires.

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Species identity matters: Functional responses to warming in congeneric turfs differ from those of a canopy algae but are species-specific

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2021.107396 ◽

2021 ◽

pp. 107396

Author(s):

Isabella Provera ◽

Cristina Piñeiro-Corbeira ◽

Rodolfo Barreiro ◽

Laura Díaz-Acosta ◽

Pilar Díaz-Tapia

Keyword(s):

Functional Responses ◽

Species Identity ◽

Species Specific ◽

Canopy Algae

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Functional response of Harmonia axyridis preying on Acyrthosiphon pisum nymphs: the effect of temperature

Scientific Reports ◽

10.1038/s41598-021-92954-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yasir Islam ◽

Farhan Mahmood Shah ◽

Xu Rubing ◽

Muhammad Razaq ◽

Miao Yabo ◽

...

Keyword(s):

Functional Response ◽

High Performance ◽

Acyrthosiphon Pisum ◽

Harmonia Axyridis ◽

Effect Of Temperature ◽

Functional Responses ◽

Aphid Control ◽

Host Aphid ◽

Predator Foraging

AbstractIn the current study, we investigated the functional response of Harmonia axyridis adults and larvae foraging on Acyrthosiphon pisum nymphs at temperatures between 15 and 35 °C. Logistic regression and Roger’s random predator models were employed to determine the type and parameters of the functional response. Harmonia axyridis larvae and adults exhibited Type II functional responses to A. pisum, and warming increased both the predation activity and host aphid control mortality. Female and 4th instar H. axyridis consumed the most aphids. For fourth instar larvae and female H. axyridis adults, the successful attack rates were 0.23 ± 0.014 h−1 and 0.25 ± 0.015 h−1; the handling times were 0.13 ± 0.005 h and 0.16 ± 0.004 h; and the estimated maximum predation rates were 181.28 ± 14.54 and 153.85 ± 4.06, respectively. These findings accentuate the high performance of 4th instar and female H. axyridis and the role of temperature in their efficiency. Further, we discussed such temperature-driven shifts in predation and prey mortality concerning prey-predator foraging interactions towards biological control.

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