scholarly journals Weather effects on birds of different size are mediated by long‐term climate and vegetation type in endangered temperate woodlands

2018 ◽  
Vol 25 (2) ◽  
pp. 675-685 ◽  
Author(s):  
David B. Lindenmayer ◽  
Peter Lane ◽  
Mason Crane ◽  
Daniel Florance ◽  
Claire N. Foster ◽  
...  

2020 ◽  
Author(s):  
David B. Lindenmayer ◽  
Peter Lane ◽  
Martin J. Westgate ◽  
Ben C. Scheele ◽  
Mason Crane ◽  
...  


2018 ◽  
Vol 46 (1) ◽  
pp. 29-51 ◽  
Author(s):  
Jean-Paul Chavas ◽  
Salvatore Di Falco ◽  
Felice Adinolfi ◽  
Fabian Capitanio


Author(s):  
Brian Miller ◽  
Hank Harlow

Our objective is to establish a long-term monitoring project that will assess the abundance and densities of selected species of mammals at sites representing five defined vegetation types found in Grand Teton National Park. The term monitoring implies data collection over multiple years. Taking long term estimations of population composition before, during, and after biotic and abiotic changes provides needed information to assess the impacts of such changes and furnish useful options for management decisions. This standardized monitoring plan will provide information on small and medium-sized mammals that will (1) assess species use of habitat, (2) monitor changes in species composition as a result of environmental change, such as precipitation and temperature, (3) produce predictive models of small and medium-sized mammal distribution based on vegetation type, and (4) analyze the impact of wolf colonization on the mammal (and plant) community.



Author(s):  
P. Das ◽  
M. D. Behera ◽  
P. S. Roy

The impact of long term climate change that imparts stress on forest could be perceived by studying the regime shift of forest ecosystem. With the change of significant precipitation, forest may go through density change around globe at different spatial and temporal scale. The 100 class high resolution (60 meter spatial resolution) Indian vegetation type map was used in this study recoded into four broad categories depending on phrenology as (i) forest, (ii) scrubland, (iii) grassland and (iv) treeless area. The percentage occupancy of forest, scrub, grass and treeless were observed as 19.9&amp;thinsp;%, 5.05&amp;thinsp;%, 1.89&amp;thinsp;% and 7.79&amp;thinsp;% respectively. Rest of the 65.37&amp;thinsp;% land area was occupied by the cropland, built-up, water body and snow covers. The majority forest cover were appended into a 5&amp;thinsp;km&amp;thinsp;&amp;times;&amp;thinsp;5&amp;thinsp;km grid, along with the mean annual precipitation taken from Bioclim data. The binary presence and absence of different vegetation categories in relates to the annual precipitation was analyzed to calculate their resilience expressed in probability values ranging from 0 to 1. Forest cover observed having resilience probability (Pr) &amp;lt;&amp;thinsp;0.3 in only 0.3&amp;thinsp;% (200&amp;thinsp;km<sup>2</sup>) of total forest cover in India, which was 4.3&amp;thinsp;% &amp;lt;&amp;thinsp;0.5&amp;thinsp;Pr. Majority of the scrubs and grass (64.92&amp;thinsp;% Pr&amp;thinsp;&amp;lt;&amp;thinsp;0.5) from North East India which were the shifting cultivation lands showing low resilience, having their high tendency to be transform to forest. These results have spatial explicitness to highlight the resilient and non-resilient distribution of forest, scrub and grass, and treeless areas in India.



2014 ◽  
Vol 27 (14) ◽  
pp. 5632-5652 ◽  
Author(s):  
R. D. Koster ◽  
G. K. Walker ◽  
G. J. Collatz ◽  
P. E. Thornton

Abstract Long-term, global offline (land only) simulations with a dynamic vegetation phenology model are used to examine the control of hydroclimate over vegetation-related quantities. First, with a control simulation, the model is shown to capture successfully (though with some bias) key observed relationships between hydroclimate and the spatial and temporal variations of phenological expression. In subsequent simulations, the model shows that (i) the global spatial variation of seasonal phenological maxima is controlled mostly by hydroclimate, irrespective of distributions in vegetation type; (ii) the occurrence of high interannual moisture-related phenological variability in grassland areas is determined by hydroclimate rather than by the specific properties of grassland; and (iii) hydroclimatic means and variability have a corresponding impact on the spatial and temporal distributions of gross primary productivity (GPP).



1991 ◽  
Vol 18 (2) ◽  
pp. 199 ◽  
Author(s):  
DC McFarland

Ground parrots in Queensland were found in closed graminoid-heathlands and sedgelands between Maryborough and Coolum on the mainland, and along the west coast of Fraser I. Parrot distribution, when compared to historical data, shows a decline which is a result of habitat destruction or degradation in the northern and southern limits of the species range. The current population is estimated at 2900 birds, with the majority in the heathlands of Cooloola National Park, Wide Bay Military Reserve and the State Forest and the Great Sandy National Park on Fraser I. Ground parrot density varied between sites because of the interactive effects of vegetation type, heathland area, time since and frequency of fire, microhabitat diversity and proximity to recolonisers. Within sites, parrot numbers changed in the long term with time since fire (influence of temporal changes in vegetation structure and seed availability) peaking at 5-8 years after burning, and in the short term with the seasonal effects of dispersal and breeding. Although predators were present their impact on the main populations was considered minimal. All of these factors are, to some extent, influenced by human activities, e.g. clearing and burning of heathlands.



1990 ◽  
Vol 68 (3) ◽  
pp. 433-441 ◽  
Author(s):  
Ian L. Jones ◽  
Anthony J. Gaston ◽  
J. Bruce Falls

We studied factors influencing variation in nightly levels of activity (birds arriving and vocalizing) and numbers of birds staging offshore at a colony of Ancient Murrelets at Reef Island, British Columbia, during 1984, 1985, and 1986. Activity was restricted to the hours of darkness and extremely variable in magnitude from night to night. The rate of entry into burrows tended to decrease, and the amount of vocalization and numbers of birds at the staging area increased during the nesting season. We detected an underlying 4-day cyclical pattern of attendance. Nightly variability of activity at the colony was affected by moonlight and weather conditions. Since activity, particularly vocalization, was reduced on moonlit nights, we suggest that nocturnal colony attendance is a strategy to avoid diurnal predators in this species. The largest numbers of birds were present and vocalizing at the colony on calm moonless nights. Weather conditions explained a substantial proportion of the night to night variability in murrelet activity. Among weather variables, wind speed had the most consistent effect and was particularly important in 1985. Both short-term, i.e., of a particular night, and long-term, i.e., over the previous 3 days, conditions influenced activity. Our observations suggest that direct weather effects at the colony may be more important than weather effects related to foraging conditions. Interyear differences in activity may have resulted from the interaction of weather and general foraging conditions.



2021 ◽  
Vol 13 (16) ◽  
pp. 9071
Author(s):  
Maria Ziaja ◽  
Tomasz Wójcik ◽  
Małgorzata Wrzesień

Phytosociological research on aquatic and marsh vegetation was conducted in Rzeszów Reservoir (SE Poland): 134 relevés according to the Braun-Blanquet method were collected there in 2016 and compared to 91 relevés published in 1994 (225 relevés in total). Changes in vegetation type, diversity measures, species composition, and Ellenberg Indicator Values (EIVs) for light, moisture, reaction, and nitrogen were analysed. Over the 22 years (1994–2016), the greatest changes were noted in communities of the classes Lemnetea and Potametea and the alliance Salicion albae. The long-term observations demonstrated the disappearance of 14 phytocoenoses and the occurrence of 12 new ones. An expansion of marsh communities (Typhetum latifoliae, Typhetum angustifoliae, Glycerietum maximae, Leersietum oryzoidis) was noted, causing a decline of several species and vegetation types. According to canonical correspondence analysis (CCA), four environmental variables (light, moisture, nitrogen, and pH) were related to plant distribution. The strong disturbances reflected in intensive eutrophication were due to human activity, which is the main factor shaping the ecological succession and overgrowing of the reservoir.



2020 ◽  
Author(s):  
Lafage Denis ◽  
Carpentier Alexandre ◽  
Sylvain Duhamel ◽  
Christine Dupuy ◽  
Eric Feunteun ◽  
...  

AbstractSalt marshes are under high, and increasing, anthropogenic pressures that have notably been reported to affect the diet of several fish species, probably resulting in nursery function alterations. Most of the previous studies in Europe were yet based on gut content analysis of fish, which can be considered a snapshot of immediate impacts of salt-marsh changes, and hardly of long-term effects of disturbances. In this study, we investigated the impact of vegetation type (resulting from both plant invasion and sheep grazing) by assessing trophic network (and especially fish diet and position) of different salt-marsh conditions. Replicated samples of basic sources (particular organic matter and microphytobenthos), dominant vegetation, potential aquatic and terrestrial prey and fish of 3 main species were taken during summer 2010 in two bays from Western France (Mont -Saint-Michel Bay and Seine Estuary) and analysed using C and N stable isotope compositions. All response variables tested (overall trophic organization, trophic niche and trophic position) provided consistent results, i.e. a dominant site effect and a weaker effect of vegetation type. Site effect was attributed to differences in anthropogenic Nitrogen inputs and tidal regime between the two bays, with more marine signatures associated with a higher frequency of flooding events. A second hypothesis is that E. acuta, which has recently totally replaced typical salt-marsh vegetation in Mont Saint-Michel Bay strongly impacted the nursery function. The trophic status of dominant fish species was unchanged by local salt-marsh vegetation, and considered consistent with their diet, i.e. high for predatory species (the sea bass Dicentrarchus labrax and the common goby Pomatoschistus microps) and lower for biofilm grazing species (the thinlip mullet Chelon ramada). This study finally highlights the relevance of stable isotopes analyses for assessing long-term and integrative effects of changes in vegetation resulting from human disturbances in salt marshes.HighlightsCross-ecosystem subsidies are of high functional importance, notably in salt marshesFish are vectors of exchanges, most European studies being based on their gut contentUsing stable isotopes we analysed the effect of surrounding vegetation on food websSurprisingly we found weak vegetation and strong site effects on all metricsNitrogen inputs, site accessibility and loss of nursery function can explain this factAbstract Figure



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