Further studies on the chipmunk warble, Cuterebra emasculator (Diptera: Cuterebridae)

1972 ◽  
Vol 50 (6) ◽  
pp. 861-864 ◽  
Author(s):  
Gordon F. Bennett

The prevalence of Cuterebra emasculator Fitch in 1328 chipmunks (Tamias striatus) was analyzed as to the sex and age class of the host and to the forest habitats from which the chipmunks were obtained. The prevalence of the parasite was highest in immature animals of both sexes and lowest in adult females. Prevalence of C. emasculator was highest in chipmunks from second-growth mixed forests; such animals also carried more parasites per animal. Chipmunks from mature coniferous forests harbored the fewest parasites per individual and the prevalence was the lowest. The parasite density was extremely low, averaging one fly per 2.8 acres in mature coniferous forest and one fly per 0.7 acres in the second-growth forest habitat.

2016 ◽  
Vol 77 (1) ◽  
pp. 32-41
Author(s):  
Damian Głowacki ◽  
Małgorzata Sławska ◽  
Marek Sławski

Abstract Based on data obtained from the Information System of Polish State Forests (SILP), we compiled a register of segments with northern red oak within the area of the Grotniki Forest District. For all of these stands, the cover of Q. rubra in the tree, understory (undergrowth and shrub layer) and herb layer was determined for at least three points and then rated on a ten-point scale (1st class – 10%, 2nd class – 20%, etc.). The current distribution of Q. rubra in all forest layers was analysed with respect to the type of forest habitat and stand age. Additionally, a prosperity index of northern red oak was calculated separately for two Forest Inspectorates and for all forest habitat types. The divisions with Q. rubra in the Grotniki Forest District comprise a total area of 4,845,86 hectares, which represents 33% of the forest district’s area. In the Grotniki Forest Inspectorate 3,447,75 hectares (38% of the forested area) and in the Glowno Forest Inspectorate 1,398,11 hectares (25%) were inventoried. In all layers of the stands, the second and the third classes of coverage were the most commonly recorded, while Q. rubra covered the largest surface area in the herb layer, which confirms that this species is spread continuously in the forest district’s stands. In the Grotniki Forest Inspectorate, Q. rubra occurred most frequently in stands of the third age class, whereas in the Głowno Forest Inspectorate stands of the fourth age class had the highest rate of occurrence. The forest habitat in which Q. rubra achieved the highest prosperity index is a moderately humid mixed coniferous forest.


2016 ◽  
Vol 25 (2) ◽  
pp. 213 ◽  
Author(s):  
Kajar Köster ◽  
Frank Berninger ◽  
Jussi Heinonsalo ◽  
Aki Lindén ◽  
Egle Köster ◽  
...  

In boreal forest ecosystems fire, fungi and bacteria, and their interactions, have a pronounced effect on soil carbon dynamics. In this study we measured enzymatic activities, litter decomposition rates, carbon stocks and fungal and microbial biomasses in a boreal subarctic coniferous forest on a four age classes of non-stand replacing fire chronosequence (2, 42, 60 and 152 years after the fire). The results show that microbial activity recovered slowly after fire and the decomposition of new litter was affected by the disturbance. The percent mass loss of Scots pine litter increased with time from the last fire. Slow litter decomposition during the first post-fire years accelerates soil organic matter accumulation that is essential for the recovery of soil biological activities. Fire reduced the enzymatic activity across all the enzyme types measured. Carbon-degrading, chitin-degrading and phosphorus-dissolving enzymes showed different responses with the time elapsed since the fire disturbance. Microbial and enzymatic activity took decades before recovering to the levels observed in old forest stands. Our study demonstrates that slower post-fire litter decomposition has a pronounced impact on the recovery of soil organic matter following forest fires in northern boreal coniferous forests.


1976 ◽  
Vol 54 (5) ◽  
pp. 620-627 ◽  
Author(s):  
J. George Gleich ◽  
Frederick F. Gilbert

Terrestrial gastropods were collected in central Maine from June to November 1971 to study their distribution, relative abundance, and habitat preferences. Gastropods were widespread, but not abundant. Thirty-five percent of the 1626 gastropods collected were slugs. Thirty-seven snail species, including eight slug species, were found. Discus cronkhitei and Zonitoides arboreus were the most commonly collected gastropods: Deroceras reliculatum and Pallifera dorsalis were the most common slugs. Snails (excluding slugs) were more abundant in the northwestern portion of central Maine, whereas slugs were more abundant in the southeastern portion. Slugs were significantly less abundant in coniferous forests than in deciduous or mixed forests, but snail numbers (excluding slugs) in the three forest types were not significantly different.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12059
Author(s):  
Min Li ◽  
Gaowei Wang ◽  
Yang Gao ◽  
Mingzhu Dou ◽  
Ziqi Wang ◽  
...  

Although myxomycetes are ubiquitous in terrestrial ecosystems, studies on their distribution and diversity in subtropical humid forests are still lacking. Field collections and moist chamber cultures were conducted from May to October within a two-year period in the Tiantangzhai National Forest Park of China. A total of 1,492 records representing 73 species belonging to 26 genera were obtained, of which 243 records/37 species were from field collections, and 1,249 records/52 species were from moist chamber cultures. Among the specimens obtained by culturing, 896 records/38 species and 353 records/37 species were obtained from living bark and ground litter, respectively. ANOVA showed that the sampling months had significant impacts on collection of myxomycetes from field and those that inhabit litter. An LEfSe analysis indicated that Arcyria was significantly abundant in August, while Stemonitis and Physarum were more abundant in July when collected from field. An RDA analysis showed that temperature was the main factor that affected the litter-inhabiting myxomycetes. The ANOVA indicated that forest type was the significant factor for bark-inhabiting myxomycetes. Diderma effusum was primarily obtained from mixed forests, while Clastoderma debaryanum and Colloderma oculatum were more common in coniferous forests. The RDA analysis indicated that the vegetation, pH, water retention, and elevation were the primary factors that affected the bark-inhabiting myxomycetes.


2012 ◽  
Vol 13 (3) ◽  
pp. 950-965 ◽  
Author(s):  
Minseok Kang ◽  
Hyojung Kwon ◽  
Jung Hwa Cheon ◽  
Joon Kim

Abstract Continuous and direct measurement of evapotranspiration (ET) by the eddy covariance (EC) technique is still a challenge under monsoon climate because of a considerable amount of missing data during the long rainy periods and the consequential gap-filling process. Under such wet canopy conditions, especially in forests, evaporation of the intercepted precipitation (EWC) contributes significantly to the total ET. To quantify the role of EWC, leaf wetness has been measured at multiple levels in the canopy simultaneously with eddy covariance measurements at the KoFlux Gwangneung deciduous and coniferous forests for the entire year from September 2007 to August 2008. In this study, the measured EWC and the controlling mechanism during the wet canopy conditions have been scrutinized. Based on the evaluation of the four different algorithms of EWC estimation, that of the variable infiltration capacity (VIC) land surface model (LSM) has been adopted. All the missing EWC data are then recalculated by using the algorithm of VIC LSM and compared against the traditionally gap-filled EWC data based on the modified lookup table (MLT) method. The latter consistently underestimated EWC on average by 39% in deciduous forest and by 28% in coniferous forest. Major causes of such differences were due to the failure of considering aerodynamic coupling, advection of sensible heat, and heat storage in the MLT-based gap-filling method. Accordingly, a new gap-filling strategy for EWC is proposed that takes proper controlling mechanisms into account.


Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1677
Author(s):  
Orsolya Juhász ◽  
Ágnes Fürjes-Mikó ◽  
Anna Tenyér ◽  
Anna Ágnes Somogyi ◽  
Dianne Joy Aguilon ◽  
...  

The consequences of anthropogenic climate change are one of the major concerns of conservation biology. A cascade of negative effects is expected to affect various ecosystems, one of which is Central European coniferous forests and their unique biota. These coniferous forests are the primary habitat of many forest specialist species such as red wood ants. Climate change-induced rising of temperature allows trees to skip winter hibernation, making them more vulnerable to storms that cause wind felling, and in turn, promotes bark beetle infestations that results in unscheduled clear-cuttings. Red wood ants can also be exposed to such habitat changes. We investigated the effects of bark beetle-induced clear-cutting and the absence of coniferous trees on colonies of Formica polyctena, including a mixed-coniferous forest as a reference. Our aim was to investigate how these habitat features affect the nest characteristics and nesting habits of F. polyctena. Our results indicate that, in the absence of conifers, F. polyctena tend to use different alternatives for nest material, colony structure, and food sources. However, the vitality of F. polyctena colonies significantly decreased (smaller nest mound volumes). Our study highlights the ecological flexibility of this forest specialist and its potential to survive under extreme conditions.


Botany ◽  
2011 ◽  
Vol 89 (11) ◽  
pp. 779-785 ◽  
Author(s):  
Bogdan Jaroszewicz ◽  
Ewa Pirożnikow

Many studies show large discrepancies between the potential (studied in the greenhouse) and realized (studied in the field) effects of endozoochory. The influence of environmental conditions on the fate of endozoochorically dispersed seeds and subsequent plant establishment is still not well understood. We addressed this issue by studying the viable seed content of the dung of European bison ( Bison bonasus L.) by means of seedling germination in the greenhouse and in two forest habitats in Białowieża Primeval Forest. The number of seedlings and the number of plant species that emerged from 1 L of feces were positively correlated with dung longevity. Generative shoots were produced by plants only in coniferous forest. Their number was positively correlated with dung longevity and with light availability. Germination of seeds from bison feces was higher in coniferous forest than in deciduous forest but did not differ between open- and closed-canopy plots within the same habitat. We conclude that (i) seed germination and plant establishment after endozoochorous dispersal is influenced by dung longevity; (ii) the number of generative shoots produced by endozoochorously dispersed plants is influenced by dung longevity and light availability; (iii) seeds of some plant species, present in dung, stay viable for at least 3 years.


1970 ◽  
Vol 48 (12) ◽  
pp. 2163-2167 ◽  
Author(s):  
Thomas Atzet ◽  
R. H. Waring

Spectroradiometric analyses were made to examine the light-filtering capacity of coniferous forests and to establish the lower limits of light energy for growth of Pseudotsuga menziesii (Mirb.) Franco, Abies concolor (Gord. and Glend.) Lindl., and Pinns ponderosa Dougl. Light energy (400–750 nm) was recorded periodically on clear days in June and July at 48 points under four mixed conifer stands and segregated into four spectral bands (blue, 400–450; green, 500–550; red, 650–700; far-red, 700–750 nm). Minor changes in the proportion of light in one band to that in another occur throughout the day, but in general the 400- to 700-nm range appears rather uniformly absorbed by a coniferous forest canopy. Averaged for an entire day, only the far-red band showed a significant proportional increase under a coniferous canopy compared to unfiltered sunlight.The relation between the energy received in each of the spectral bands and the total recorded in the 400- to 700-nm range was linear. The sampled canopies transmitted up to 25% of full sunlight. Beneath the canopies, the ratio of blue to total energy (400–700 nm) was 0.1540. Green, red, and far-red had ratios of 0.1853, 0.1220, and 0.1207.Terminal growth of 34 seedlings was measured at the light-sampling points to provide a means of establishing lower limits of light energy for survival. The lower limit for Abies and Pseudotsuga was 1.85 langleys (ly) per day (400–700 nm). Pinus grew only where the light energy exceeded 36.8 ly/day.An interaction with moisture appears to influence the minimum requirements for light energy of a species. Where moisture was adequate throughout the growing season, the lower limit of light for Pseudotsuga seedling establishment was 1.85 ly/day; where moisture became limiting, the minimum light requirement increased to 6.64 ly/day.


1966 ◽  
Vol 23 (5) ◽  
pp. 757-766 ◽  
Author(s):  
D. E. Sergeant

In less than a decade the mean age at sexual maturity of female harp seals of the Front, or northeastern Newfoundland population, decreased to 4 from [Formula: see text] years. Exploitation was heavy during this period and included a high proportion of seals older than 1 year. Females of the Gulf of St. Lawrence herd declined in mean age at sexual maturity over the same decade to 5 from nearly 6 years. Exploitation of this herd was lower, especially for animals older than their first year. Fertility of the adult females was likely higher in the more heavily exploited population. Published data on the White Sea population, which was reduced to low numbers, show reproduction at a lower mean age than for the present Front herd; for the Jan Mayen herd, of uncertain population status, about the same reproductive rate as the present Gulf herd. In most of the populations, samples of adult, whelped females showed the greatest number in the age-class about 1 year older than that first showing 100% of the females mature, as would be expected; however, samples from the Front herd showed dominance of an older age-class, suggesting that young adult females may to some extent segregate into separate groups. The immediate factors leading to increased reproductive rates at lower population densities were not elucidated.


1991 ◽  
Vol 18 (3) ◽  
pp. 255-259 ◽  
Author(s):  
Harald Korsmo

In this paper, it is argued that the Norwegian Government must tackle the problems related to the conservation of coniferous forests more seriously and urgently than hitherto, and not let this important task be governed by commercial interests. A national plan based on political, non-scientific motives will not safeguard these ecocomplexes and their component ecosystems and the endangered species found in them.A practical way to solve the time-consuming disagreements between environmental authorities and forest owners would be to guarantee full compensation, and to start paying for sites of high conservation interest immediately. This compensation must ensure that the forest owners can fulfil such financial commitments as they already have. An alternative would be the exchange of privately-owned forest for public forest land, including forests owned by ‘The Educational Fund’.The Ministries involved must learn to cooperate in such work. If they do not, Norway's credibility in environmental matters may suffer. Solutions must be reached which do not put sectorial interests before national or international environmental values, and which guarantee the protection of a representative selection of coniferous forests according to scientific principles.


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