Dynamic Microclimate Boundaries across a Sharp Tropical Rainforest–Clearing Edge

As landscapes become increasingly fragmented, research into impacts from disturbance and how edges affect vegetation and community structure has become more important. Descriptive studies on how microclimate changes across sharp transition zones have long existed in the literature and recently more attention has been focused on understanding the dynamic patterns of microclimate associated with forest edges. Increasing concern about forest fragmentation has led to new technologies for modeling forest microclimates. However, forest boundaries pose important challenges to not only microclimate modeling but also sampling regimes in order to capture the diurnal and seasonal dynamic aspects of microclimate along forest edges. We measured microclimatic variables across a sharp boundary from a clearing into primary lowland tropical rainforest at La Selva Biological Station in Costa Rica. Dynamic changes in diurnal microclimate were measured along three replicated transects, approximately 30 m in length with data collected every 1 m continuously at 30 min intervals for 24 h with a mobile sensor platform supported by a cable infrastructure. We found that a first-order polynomial fit using piece-wise regression provided the most consistent estimation of the forest edge, relative to the visual edge, although we found no “best” sensing parameter as all measurements varied. Edge location estimates based on daytime net shortwave radiation had less difference from the visual edge than other shortwave measurements, but estimates made throughout the day with downward-facing or net infrared radiation sensors were more consistent and closer to the visual edge than any other measurement. This research contributes to the relatively small number of studies that have directly measured diurnal temporal and spatial patterns of microclimate variation across forest edges and demonstrates the use of a flexible mobile platform that enables repeated, high-resolution measurements of gradients of microclimate.

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20 Jahre ökologische Aufwertung von Waldrändern im Kanton Aargau: erste Erfolgskontrolle

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2014.0313 ◽

2014 ◽

Vol 165 (10) ◽

pp. 313-320 ◽

Cited By ~ 1

Author(s):

Kaspar Spörri ◽

Manuel Babbi ◽

Bertil O. Krüsi

Keyword(s):

Success Factors ◽

Good Condition ◽

Forest Edge ◽

Ecological Condition ◽

Deciduous Tree ◽

Forest Edges ◽

Ecological Value ◽

Transition Zones ◽

Performance Reviews ◽

Potential Success

20 years of ecological forest edge enhancement in the Canton of Aargau: a first evaluation On the Swiss Plateau, 25 000 km of forest edges serve as transition zones between open grasslands and closed forests. They fulfil important functions with regard to ecological connectivity and constitute a habitat for numerous plant and animal species. Since only a fraction of these forest edges are in good ecological condition, most cantons implement programs to enhance their quality. With almost 200 km of upgraded forest edges, the Canton of Aargau takes on a pioneering role throughout Switzerland. To date, however, it was unknown what ecological value the upgraded forest edges have and which factors significantly contribute to the success of the implemented measures. We used a standardised evaluation key and interviews with the responsible forest services to assess the ecological quality of 20 selected forest edges in six forest districts in the Canton of Aargau as well as potential success factors. Our investigations show that enhanced forest edges in the Canton of Aargau are in a very good condition. The two most important structural elements of a forest edge in terms of biodiversity are two to eight times more marked than on average on a national scale, and they nearly conform to the objectives as defined by nature conservancy. With a registered total of 31 domestic deciduous tree species and 58 domestic lignified plant species, floristic diversity is remarkably high. Contrary to the estimation of the responsible forest services, neither the vigour of a location nor its aspect proved to be decisive factors of success. Rather, the frequency of intervention seems to be critical. Maintenance measures should be implemented at least every seven years. More comprehensive analyses are necessary to corroborate the present findings for other regions in Switzerland. Precondition for such analyses are systematic performance reviews that include an examination of the baseline conditions.

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Studies of Ant-Following Birds North of the Eastern Amazon

Acta Amazonica ◽

10.1590/1809-43921972022127 ◽

1972 ◽

Vol 2 (2) ◽

pp. 127-151 ◽

Cited By ~ 12

Author(s):

Yoshika Oniki ◽

Edwin O. Willis

Keyword(s):

Forest Edge ◽

Forest Edges ◽

Army Ants ◽

Forest Interior ◽

Second Growth

Abstract Birds that prey on arthropods flushed by army ants north of the eastern Amazon were studied at Serra do Navio and Reserva Ducke (Brazil) and at Nappi Creek and Bartica (Guyana). Regular ant-followers are two medium-sized antbirds (Percnostola rufifrons and Gymnopithys rufigula) and two smaller ones (Pithys albifrons and Hylophylax poecilonota), plus five woodcreepers of differing sizes (from very large Hylexetastes perrotti through Dendrocolaptes picumnus, D. certhia, and Dendrocincla merula to medium-sized Dendrocincla fuliginosa). Four other regular ant-followers occur in the region but were not found at the study areas. Forty-five species of casual or nonprofessional ant-followers, including 16 antbirds, 5 woodcreepers, and 5 manakins, also were recorded. Percnostola rufifrons tends to be at the forest edge or in second growth. Pithys albifrons works around Gymnopithys rufigula, Hylophylax poecilonota peripheral to both, in the forest interior. The large Dendrocolaptes picumnus and medium-large Dendrocincla merula often capture prey near the ground, like antbirds. Unlike antbirds, which use vertical or horizontal slender perches, the woodcreepers use thick vertical perches. Dendrocolaptes certhia and Dendrocincla fuliginosa also tend to capture prey high over the ground-foraging antbirds. The woodcreepers tend to forage lower at midday. Hylexetastes perrotti is rare, and overlaps strongly with D. picumnus. There is fairly large overlap among the 9 professional ant-followers, and large ones chase away smaller ones. Nonprofessional birds tend to forage briefly or peripherally when or slightly after the professional species are active. They also forage above the antbirds and below or above the woodcreepers, and concentrate at forest edges or in second growth. The guild of ant-following birds in this region differs fairly widely from guilds in Panamá and at Belém, Brazil; the absence of large antbirds and the predominance of large woodcreepers north of the Amazon are the major differences.

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Preadaptation and spatial effects on retention-tree survival in cut areas in Estonia

Canadian Journal of Forest Research ◽

10.1139/x08-093 ◽

2008 ◽

Vol 38 (10) ◽

pp. 2616-2625 ◽

Cited By ~ 31

Author(s):

Raul Rosenvald ◽

Asko Lõhmus ◽

Andres Kiviste

Keyword(s):

Natural Disturbance ◽

Forest Edge ◽

Forest Site ◽

Spatial Effects ◽

Forest Edges ◽

Dead Trees ◽

Tree Survival ◽

Tree Retention ◽

Standing Dead ◽

Retention Trees

Survival of live retention trees is a key issue for stand-scale applications of natural-disturbance-based silviculture. We explored the survival of 3255 trees in 102 cut areas (mean size 2.3 ha) in Estonia for 6 years, focusing on spatial variation and preadaptation of the trees. Altogether, 35% of the trees died during the study period, contributing 4.4 m3 of downed dead trunks and 1 m3 of standing dead trees per hectare. The annual mortality rates declined over time. The main survival determinants were tree species (higher for hardwood deciduous trees), diameter (species dependent), position relative to forest edge (higher for trees near current or former forest edges), retention density (positive), and exposure (negative). The results suggest that (1) green-tree retention can effectively increase the abundance of large shade-tolerant trees, but it is equally important for producing deadwood; (2) larger individuals, former interior-forest trees near current forest edges, and preadapted trees in open conditions should be preferably retained; (3) there is no obvious necessity to modify tree-retention techniques for tree survival according to geographical region or forest site type.

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ONTOGENESIS AND AGE STRUCTURE OF ADONIS VERNALIS L. POPULATIONS IN THE CONDITIONS OF NORTHERN KAZAKHSTAN

THE BULLETIN ◽

10.32014/2020.2518-1467.143 ◽

2020 ◽

Vol 5 (387) ◽

pp. 56-64

Author(s):

G.J. Sultangazina ◽

◽

А.N. Kuprijanov ◽

О.А. Kuprijanov ◽

R.S. Beyshov ◽

...

Keyword(s):

Age Structure ◽

Field Research ◽

Forest Edge ◽

Forest Steppe ◽

Forest Edges ◽

Recovery Index ◽

Northern Kazakhstan ◽

Age Related ◽

Study Results ◽

Current Article

The current article presents study results made on the coenoflora of Adonis vernalis L. in Northern Kazakhstan. The materials have been gathered in the course of field research taking into account the literary data. Ontogenesis and age structure of the coenopopulations are provided on the basis of detailed-route studies. The study of age-related stages was carried out on the territory of Northern Kazakhstan (Akmola and North Kazakhstan regions) in 2018-2019. A. vernalis is a short-stem grassy polycarpic plant, it is represented in Northern Kazakhstan by the populations of dry meadows (Kokshetau Upland) and real meadows (the forest-steppe of North Kazakhstan region). Ontogenesis of A. vernalis has three periods and 7 age stages. Plants have low seed productivity. Seeds have a long endogenous peace related to the underdevelopment of a seed germ. A characteristic feature is the presence of a long pregenerative period in plants of the "steppe" type coenopopulations and its reduction in the "meadow" type coenopopulations. There have been studied thirteen coenopopulations of A. vernalis located in Akmola and North Kazakhstan regions. Coenopopulations of A. vernalis are bound to four main habitats: forest edges, meadow steppes, meadows, artificial plantations. By age, young populations are formed on forest edges, and according to the "delta - omega" classification, there are mature coenopopulations. Mature coenopopulations are mostly formed in meadow steppes, but according to the "delta - omega" classification, all coenopopulations are aging. On meadows, there are many young coenopopulations, but according to the "delta - omega" classification, they are all mature. In artificial plantings, the majority of coenopopulations are aging, but according to the "delta - omega" classification, they are all mature. Thus, changes in habitual living conditions lead to the aging of A. vernalis coenopopulations. By density (pcs/100 m2) all populations are divided into three groups: high, medium, low. All forest edge coenopopulations have a high density, in meadow steppes, the density is average, on meadows and in artificial plantings it is low. The recovery index in most coenopopulations is less than one which indicates a low recovery in A. vernalis populations. The range of age stages shows that in most coenopopulations they are normal, the exception is CP-5 (among artificial plantings) which indicates an old stage of the population and possibly its soon elimination.

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The Spatial Response of Male Hooded Warblers to Edges in Isolated Fragments

The Condor ◽

10.1093/condor/102.3.595 ◽

2000 ◽

Vol 102 (3) ◽

pp. 595-600 ◽

Cited By ~ 2

Author(s):

D. Ryan Norris ◽

Bridget J. M. Stutchbury ◽

Trevor E. Pitcher

Keyword(s):

Space Use ◽

Forest Edge ◽

Time Of Day ◽

Forest Edges ◽

Forest Patches ◽

Wilsonia Citrina ◽

Use Patterns ◽

Continuous Forest ◽

Hooded Warblers ◽

Occupancy Rates

Abstract We tested whether Hooded Warblers (Wilsonia citrina) avoided abrupt forest edges by radiotracking males breeding in small, isolated forest patches (0.5–2.0 ha) in northwest Pennsylvania. Because territory edges were synonymous with abrupt forest edges in all cases, we compared space use patterns with males radiotracked in a nearby continuous forest (150 ha), where we defined edge from territorial boundaries. Based on the proportion of edge to core area, males in both habitats avoided the area within 20 m of the edge, implying that males responded to the presence of territory edge rather than forest edge. Surprisingly, however, males in isolated fragments used the edge area significantly more than males in continuous forest, even when measured against the relative amount of edge area within each territory. Elevated levels of edge use were not related to distance of nests to edges, nest stage, or time of day. We conclude that the presence of physical edges is not the sole determinant of territorial space use in this species and there are likely additional social factors influencing occupancy rates in small, isolated woodlots. Therefore, definitions of forest-interior species based on edge use need to be reconsidered.

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Hotplate precipitation gauge calibrations and field measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-11-441-2018 ◽

2018 ◽

Vol 11 (1) ◽

pp. 441-458 ◽

Cited By ~ 1

Author(s):

Nicholas Zelasko ◽

Adam Wettlaufer ◽

Bujidmaa Borkhuu ◽

Matthew Burkhart ◽

Leah S. Campbell ◽

...

Keyword(s):

Energy Conversion ◽

Surface Area ◽

Conversion Factor ◽

Field Measurements ◽

Radiative Properties ◽

Shortwave Radiation ◽

Actual Surface ◽

Precipitation Gauge ◽

Radiation Sensors ◽

S Application

Abstract. First introduced in 2003, approximately 70 Yankee Environmental Systems (YES) hotplate precipitation gauges have been purchased by researchers and operational meteorologists. A version of the YES hotplate is described in Rasmussen et al. (2011; R11). Presented here is testing of a newer version of the hotplate; this device is equipped with longwave and shortwave radiation sensors. Hotplate surface temperature, coefficients describing natural and forced convective sensible energy transfer, and radiative properties (longwave emissivity and shortwave reflectance) are reported for two of the new-version YES hotplates. These parameters are applied in a new algorithm and are used to derive liquid-equivalent accumulations (snowfall and rainfall), and these accumulations are compared to values derived by the internal algorithm used in the YES hotplates (hotplate-derived accumulations). In contrast with R11, the new algorithm accounts for radiative terms in a hotplate's energy budget, applies an energy conversion factor which does not differ from a theoretical energy conversion factor, and applies a surface area that is correct for the YES hotplate. Radiative effects are shown to be relatively unimportant for the precipitation events analyzed. In addition, this work documents a 10 % difference between the hotplate-derived and new-algorithm-derived accumulations. This difference seems consistent with R11's application of a hotplate surface area that deviates from the actual surface area of the YES hotplate and with R11's recommendation for an energy conversion factor that differs from that calculated using thermodynamic theory.

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Forest edges and the soil-vegetation- atmosphere interaction at the landscape scale: the state of affairs

Progress in Physical Geography Earth and Environment ◽

10.1177/030913339602000303 ◽

1996 ◽

Vol 20 (3) ◽

pp. 292-310 ◽

Cited By ~ 22

Author(s):

Arthur W. L. Veen ◽

Wim Klaassen ◽

Bart Kruijt ◽

Ronald W.A. Hutjes

Keyword(s):

Experimental Evidence ◽

Forest Edge ◽

Landscape Scale ◽

Small Scale ◽

Forest Edges ◽

Surface Type ◽

Heterogeneous Landscape ◽

Atmosphere Interaction ◽

State Of Affairs ◽

The Impact

Although the soil-vegetation-atmosphere exchange of momentum and heat is fairly well understood for many types of homogeneous surfaces, the disturbances created by tran sitions of one surface type to another remain to be analysed more fully. This is especially true for the impact which a large transition such as the forest edge has on the average fluxes in a small-scale heterogeneous landscape with forest. Recently acquired experimental evidence appears to some extent contradictory and at variance with conventional concepts.

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Forest Edge Effects on Seedlings in Mixed Oriental Beech (Fagus orientalis Lipsky) - Scots Pine (Pinus sylvestris L.) Stands

10.20944/preprints201811.0174.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Osman Topaçoğlu ◽

Emre Genç

Keyword(s):

Scots Pine ◽

Basal Area ◽

Forest Edge ◽

Height Growth ◽

Forest Edges ◽

Seedling Density ◽

Oriental Beech ◽

Pine Seedlings ◽

Fagus Orientalis Lipsky ◽

Stand Basal Area

Forest edges created by silvicultural treatment influence micro-climatic conditions and available light in forest stands. Studies regarding the impacts of forest edges on regeneration is limited in mixed Oriental beech (Fagus orientalis Lipsky)-Scots pine (Pinus sylvestris L.) stands. In this study, the influences of forest edges on height growth, root-collar diameter (RCD) growth and density of seedlings in an adjacent stand of Oriental beech-Scots pine were observed. In addition, the effects of stand basal area and height-to-crown base (HCB) on height growth, RCD growth and seedlings density were monitored. The study was conducted within Samatlar Forest Planning Directorate, in Kastamonu city, Turkey. In the selected Oriental beech-Scots pine stand, twenty-five transects were installed perpendicular to the forest edge, and all the measurements were taken within these transects. There were statistically significant relationships between the distance from the forest edge and the growth of Scots pine seedlings (p<0.05), while the stand edge did not have any effect on the growth of Oriental beech seedlings. Density of Scots pine seedlings decreased, while Oriental beech seedling density increased from the edge into the intact stand (p<0.05). Stand basal area and HCB did not significantly change from the edge into the intact stand (p>0.05). The differences in seedling growth and seedling density between the two species can be associated with their dissimilar tolerance to shade. The initial results obtained in this study point out the importance of forest edges on the regeneration of Oriental beech and Scots pine seedlings. Data suggest that regeneration of mixed Oriental beech-Scots pine should be successful using group methods rather than traditional shelterwood method within entire stand.

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Edge effects on the distribution and abundance of birds in a southern Victorian forest

Wildlife Research ◽

10.1071/wr00057 ◽

2001 ◽

Vol 28 (3) ◽

pp. 239 ◽

Cited By ~ 19

Author(s):

Lainie Berry

Keyword(s):

Habitat Fragmentation ◽

Bird Species ◽

Forest Edge ◽

Bird Communities ◽

Forest Edges ◽

Forest Interior ◽

Open Country ◽

Habitat Edge ◽

Malurus Cyaneus ◽

Grey Shrike

An important consequence of habitat fragmentation for wildlife communities is the effect of an increase in the ratio of habitat edge to interior. This study compares the bird communities at forest/farmland edges and in forest interior at Bunyip State Park, Victoria. Overall, there was a significantly higher number of bird species and individuals in forest edge than in forest interior sites. The greater diversity of species at edge sites appeared to be due to an increase in forest-edge specialists, as opposed to an influx of open-country species. Four bird species: the white-throated treecreeper (Cormobates leucophaeus), the superb fairy-wren (Malurus cyaneus), the grey shrike-thrush (Colluricincla harmonica) and the grey fantail (Rhipidura fuliginosa) were significantly more abundant in edge sites. There were no species that were significantly more abundant in interior sites. Differences between the bird communities in edge and interior sites were attributed to increased foraging opportunities in the open country adjacent to forest edges.

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Predation rates of artificial nests in the edge and interior of a southern Victorian forest

Wildlife Research ◽

10.1071/wr01022 ◽

2002 ◽

Vol 29 (4) ◽

pp. 341 ◽

Cited By ~ 12

Author(s):

Lainie Berry

Keyword(s):

Small Mammals ◽

Nest Predation ◽

Forest Edge ◽

Forest Edges ◽

Artificial Nests ◽

Avian Predators ◽

Forest Interior ◽

Grey Shrike ◽

Predation Rates

Predation rates of nests at human-induced habitat edges may be greater than in forest interior due to differences in predator assemblages and predator activity. I compared the predation rates on 192 artificial nests containing plasticine eggs placed in forest edge and interior sites at Bunyip State Park, Victoria. The nest-predation rates at the forest edge sites were significantly greater (mean = 52–58%) than that at the forest interior sites (mean = 30–39%). The relative rates of predation by birds compared with mammals were significantly greater at forest edge sites (mean = 78–94%) than at forest interior sites (mean = 36–67%). Higher rates of nest predation at forest edges appeared to be due to greater densities of avian predators such as the grey shrike-thrush (Colluricincla harmonica), and/or lower abundances of small mammals. However, biases towards certain predator types may mask real, or create false, patterns in predation rates of artificial nests. A better understanding of how predators respond to artificial nests compared with natural nests is required. Until then, results of predation studies that use artificial nests should be interpreted with caution.

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