Disturbance intensity and seasonality affect the resprouting ability of the neotropical dry-forest tree Acacia pennatula: do resources stored below-ground matter?

2011 ◽  
Vol 27 (5) ◽  
pp. 539-546 ◽  
Author(s):  
Guille Peguero ◽  
Josep Maria Espelta

Abstract:Many plant species in tropical dry forests partly base their ability to persist after disturbance on resprouting. Yet little is known if this ability can be affected by the intensity and seasonality of disturbance and whether the amount of resources (starch, N, P) stored in the taproot may constrain this response. We investigated resprouting after experimental clipping or burning, applied before or after the dry season and repeatedly in Acacia pennatula individuals in wooded rangelands of North-West Nicaragua. Each treatment was applied to 12 trees and replicated in six plots. One year after the onset of the experiment, survival and biomass recovery were significantly lower in burned than in clipped individuals (78% ± 4% and 75.3 ± 8.0 g vs. 94% ± 2% and 79.1 ± 6.8 g; mean ± SE). Whatever the disturbance applied, trees disturbed after the dry season significantly showed the lowest survival, growth and concentration of N and P. These results suggest that resprouting in dry tropical species may be constrained by intense disturbances (e.g. burning) but especially if they occur towards the end of the dry season. This phenological constraint could be due to the reduced availability of N and P as this dry season progresses.

Biotropica ◽  
2005 ◽  
Vol 37 (4) ◽  
pp. 547-560 ◽  
Author(s):  
John A. Gamon ◽  
Kaoru Kitajima ◽  
Stephen S. Mulkey ◽  
Lydia Serrano ◽  
S. Joseph Wright

2015 ◽  
pp. 1117-1119
Author(s):  
Christopher Vaughan ◽  
Sheila Shoenfelder

Se estudió el armadill o (Dasypus novemcinctus Linnaeus) en Palo Verde, Costa Rica (10030'N y 8So30'W) equipando siete animales con radiotransmisores. No hubo actividad en 0600-1500 h Y ésta fue máxima en 1800-2100 h (95%). Los desplazamientos nocturnos fueron de 421.4 m (223-835 m. Seis individuos usaron 14 madrigueras en cuatro tipos de hábitat


2002 ◽  
pp. 32-43
Author(s):  
V. I. Vlasenko ◽  
M. G. Erunova ◽  
I. S. Scerbinina

The reserve “Stolby” is characteristic key plot of the mountain-taiga and subtaiga-forest steppe altitudinal belts in the East Sayan Mountains, where anthropogenic influence is the least pronounced. It was founded in 1925, in 15 km southward of Krasnoyarsk city, on north-west spurs of the Western Sayan Mountains which adjoin closely to right bank of the Yenisei River bordering upon the Middle Siberian Plateau. Reserve's physiography is characterized by low mountain and middle mountain erosion-accumulation relief with absolute heights of 200-800 m. Low mountain part (200-500 m) is composed of loose sedimentary rocks. In the middle mountain part of the reserve (500-800 m) there are outcrops of sienite rocks of various stages of destruction. Vegetation and soils of the reserve change in agreement with absolute heights and climate. In low mountains spread the subtaiga and forest-steppe leaved-light needle forests on mountain grey forest soils (8.1 % of reserve territory); the middle mountain part is occupied by the light needle and dark needle taiga forests on mountain podzol soils (91.9 % of the area). As the basement for vegetation map we took the map of forest environments of reserve by T. N. Butorina compiled according to materials of land forest management of 1977 year. As the result of forest management near 2000 biogeocoenoses were distinguished. The type of biogeocoenosis, according to V. N. Sukachev, is selected as mapping unit. Biogeocoenoses were united into 70 groups of forest types, representing 21 series of associations which are reflected in the map legend (Fig. 1). The main goal of map is to show the territorial distribution of groups and series of types of biogeocoenoses in the main structural units - altitudinal be't complexes (ВПК) which are equivalents of altitudinal vegetation belts. For designation of forest tree species various kinds of hatches were used. Formations of Siberian pine, larch, pine, fir, spruce, birch and aspen forests are shown on the map. Within the ВПК arabic numerals show the groups of types of biogeocoenoses (forest types), united into series according to similarity of dominants in ground layer. The mountain-taiga ВПК includes the following series and groups of types of biogeocoenoses: dwarf-shrub-moss (1-4); sedge-moss (5-9); bilberry-low herb-moss (10-14); tall herb-sedge (15-19); tall herb-wood sour-moss (20-26); tall herb-small reed (27-32). The subtaiga-forest steppe ВГ1К embraces: shrub steppificated (33-34); shrub-forb steppificated (35-38): sedge- bilberry (39-40); sedge-forb (41-43); bracken (44); small reed-forb (45); bilberrv-forb- sedge (46, 47); forb-tall herb (48-51); tall herb (52-55); wet tall herb-small reed (56-59); fern-tall herb (60). Intrazonal phytocoenoses: brook tall herb (61-63); brook shrub (64-68); lichen-moss (69); cowberry (70). In 1999-2000 on the base of topographic map in a scale 1 : 25 000, map of forest environments, transformed by us into vegetation map of the reserve, M. J . Erunova and I. S. Scerbinina worked out an electronic variant. For this project the instrumental facilities of GIS, GeoDraw and GeoGraph (CGI IG RAS, Moscow) and programs of Geophyt were used.


Author(s):  
Bjørn Thomassen ◽  
Johannes Kyed ◽  
Agnete Steenfelt ◽  
Tapani Tukiainen

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Thomassen, B., Kyed, J., Steenfelt, A., & Tukiainen, T. (1999). Upernavik 98: reconnaissance mineral exploration in North-West Greenland. Geology of Greenland Survey Bulletin, 183, 39-45. https://doi.org/10.34194/ggub.v183.5203 _______________ The Upernavik 98 project is a one-year project aimed at the acquisition of information on mineral occurrences and potential in North-West Greenland between Upernavik and Kap Seddon, i.e. from 72°30′ to 75°30′N (Fig. 1A). A similar project, Karrat 97, was carried out in 1997 in the Uummannaq region 70°30′–72°30′N (Steenfelt et al. 1998a). Both are joint projects between the Geological Survey of Denmark and Greenland (GEUS) and the Bureau of Minerals and Petroleum (BMP), Government of Greenland, and wholly funded by the latter. The main purpose of the projects is to attract the interest of the mining industry. The field work comprised systematic drainage sampling, reconnaissance mineral exploration and spectroradiometric measurements of rock surfaces.


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