Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FORESTRY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,603 records · Page 89Linked to original sources
PubMed2005

Tree species diversity and composition in logged and unlogged rainforest of Kudremukh National Park, South India.

Species composition and diversity in logged and unlogged forests were assesed to understand the regeneration of the residual stand twenty years after logging in Kudremukh National Park, South India. Relative density, frequency and basal area were measured by Point Centered Quarter method to calculate the diversity and stand quality. The logged forest harbored lower stem density of mature trees (508 ha(-1)) than unlogged ones (630 ha(-1)). Indeed, logging operations increased the species diversity in the regenerative phase (seedling phase) due to the creation of larger canopy gaps. The extra radiation reaching the ground, facilitated the colonization of early and late secondary species. Ramakrishanan Index of Stand Quality (RISQ) values in logged forest was higher in comparison with unlogged forest, indicating the dominance of early and late secondary species, especially at sapling phase. The light demanding secondary forest species contribute higher percentage to the overall tree population in logged forest. It is observed from the study that a sufficient period of felling cycle should be practiced to reinstate the same set of species prevailed before logging.

Biodiversity↗
PubMed2006

Willow (Salix fragilis Linn.): A multipurpose tree species under pest attack in the cold desert of Lahaul valley, northwestern Himalaya, India.

Salix fragilis is the most common willow species grown extensively under the indigenous agroforestry system in the cold desert of Lahaul valley located in the northwestern Himalayas, India. Presently, this tree is under severe pest attack, and other infections have made its survival in the area questionable. This deciduous multipurpose tree species provides vegetation cover to the barren landscape of Lahaul and is a significant contributor of fuel and fodder to the region. This study is a detailed profile of the plant in three villages within this region: Khoksar, Jahlma, and Hinsa. The willow provided 69.5%, 29%, and 42% of the total fuelwood requirements of Jahlma, Khoksar, and Hinsa respectively. A striking observation was that only 30.0 +/- 20.1% trees were healthy: 55.2 +/- 16.1% of the willows have dried up and 14.8 +/- 6.1% were in drying condition due to a combination of pest infestation and infection. To sustain this cultivation of willow under the existing agroforestry system in the region, we recommend that locally available wild species and other established varieties of willow growing in similar regions of the Himalayas be introduced on a trial basis.

Altitude↗
PubMed2006

Validation of a questionnaire used to assess safety and professionalism among arborists.

This article summarizes a validation study of an instrument designed to measure safety and professionalism practices of arborists. A sample of 386 arborists from the State of Louisiana responded to the 58-item questionnaire. Analyses focused on several aspects of Messick's validation framework. Structural validity evidence was provided by analyses that indicate that the measures are unidimensional. Content validity evidence was supported by generally high positive values of the biserial correlations and optimal values of standardized mean-square item fit indices. Substantive validity evidence was provided by analyses that support the use of the two-point rating scale and a rank ordering of item means that is consistent with substantive theory. Person fit indices indicated little misfit among measures. Support for the generalizability aspect of validity was provided by an acceptable level of internal consistency and fairly tight error bands around estimated arborist measures. Additionally, few items exhibited DIF. Finally, with respect to the external aspect of validity, group differences between arborist measures were consistent with substantive theory.

Adult↗
PubMed2006

[Roles of forest management in global carbon dioxide mitigation].

This paper summarized the roles of current forest management measures, e. g., reducing deforestation rate, increasing afforestation and reforestation, strengthening the management of nutrient fertilization, fire hazard, and disease and pest injury, and substituting fossils fuels with charcoal, in global carbon dioxide migration, and analyzed the advantage and insufficiency of China's forest management. The authors indicated that the current forest ecosystems in China, mainly their vegetation carbon pool, played a smaller role of carbon sink in global carbon cycle, and thus, it was important to strengthen the tending of newly cultivated plantation and the management of fire hazard and disease and pest injury, and to increase the carbon sequestration of our forests.

Atmosphere↗
PubMed2006

[Neighborhood comparison of Cryptomeria fortunei plantation by using different variables].

Neighborhood comparison is defined as the proportion of the nearest greater neighbors to a given reference tree measured by a certain variable. By this way, the dominant differentiation degree of individual wood could be measured well. In this paper, the variables DBH, biomass, canopy breadth, and tree height were used to make the neighborhood comparison of Cryptomeria fortunei plantation in Chongzhou forest farm. The results showed that the neighborhood comparison measured by DBH and biomass had a slight fluctuation range and the highest reliability. Nevertheless, due to the effects of various tree types, the neighborhood comparison measured by canopy breath and tree height was not as reliable as that measured by the former two variables. The average value of the neighborhood comparison measured by DBH and biomass was visibly higher than that by canopy breath and tree height, indicating that the differentiation degree of individual's DBH and biomass was further greater than that of individual's canopy breath and tree height. It was possible that increasing individual's DBH to enhance its biomass, and thus, to achieve its predominance status among individuals' competition was the main strategy of individual's differentiation. Neighborhood comparison should also be taken as an instructive reference in modifying the spatial structure of stand.

Biomass↗
PubMed2006

Monitoring changes in forest and other land use forms in Istanbul.

This study introduces the monitoring system to be established within this project, it aims to determine changes occurring within forested areas, settlement areas and other land use forms located at the peripheral area of Istanbul during consecutive decades. The first phase of the study was completed in 1998 and published, covering the period from 1984 to 1994. This study is the second phase of the first one and implemented to determine land use changes which have occurred on the same site from 1994 to 2000. Standard topographic maps with 1/25 000 scale, forest management maps with the same scale, results of the previous study, orthophoto maps of the year 2000 that were produced from aerial color photographs of the site with 1/5 000 scale, and 4-band IRS_LISS III multispectral satellite data for July 2000 were used as data. The changes in land use within the study area occurring during a six year period were studied.

Conservation of Natural Resources↗
PubMedDate not supplied

[Hemorrhagic fever with renal syndrome in Croatia: incidence of infection in human and wild animal reservoirs].

On the territory of Lika and Gorski Kotar a group of 300 forest workers and 260 persons from the general population were screened for Hantavirus antibodies (by the indirect immunofluorescence test). In the first group of examenees a mean of 1.6% were found positive, ranging from 0% (Gospić) to 3.2% (Ogulin). In the second groups a mean of 5.4% were positive, ranging from 4.4 to 8.9% (Delnice and Slunj, respectively). It is concluded that the Hantavirus infection rate in our natural foci of HFRS is higher than officially registered. Screening of micromammals for the presence of Hantavirus in their organs (lungs), using the direct immunofluorescence test, was undertaken on three locations: Planina Gornja (hillsides of the mountain Medvednica), a case of HFRS having been registered there previously, and Plitvicka Jezera and Velika Gorica (village of Kobilić) selected because of two previous epidemics of HFRS (1967 and 1989, respectively). On the first location, all 126 animals examined (10 different species) were Hantavirus negative. On the second location, 9 of the 165 animals examined (three species) were Hantavirus positive (5.4%), namely 6 bank voles (Clethrionomys glareolus) and three yellow-necked mice (Apodemus flavicollis). On the third location, where 141 animals was caught and examined (7 different species), 7 animals were positive (4.9%): 3 striped field mice (A. agrarius), 3 wood mice (A. sylvaticus) and 1 bank vole (Cl. glareolus). The findings suggest that in our natural foci of HFRS the circulation of the Hantavirus is sustained by several species of micromammals.

Animals↗
PubMed2006

[Comparison of two types of diagnostic test detecting antibodies against Borrelia burgdorferi: EIA based on one genospecies antigens and ELISA based on recombinant antigens].

The aim of the study was to compare the results of ELISA diagnostic kit detecting antibodies against B. burgdorferi based on combination of three genospecies recombinant and EIA kits based on one of three genospecies. Sera of 351 forest workers were evaluated with ELISA kit (Recombinant antigen, IgG). Seropositive samples were tested with EIA kits based on B. burgdorferi s.s., B. garinii, B. afzelii antigens. Diagnostic kits based on combination of antigens of three genospecies more often detect antibodies against B. burgdorferi and are more usefull as screening tests, in comparison with those based on one genospecies. Among diagnostic kits based on one genospecies, the most sesnitive in detection of antibodies against B. burgdorferi are those based on B. afzelii.

Agricultural Workers' Diseases↗
PubMed2004

[Lyme borreliosis situation in North Africa].

Many epidemiological studies were conducted for studying Lyme borreliosis (LB) which represents a new global public health problem. It is now the most common vector-borne disease in Europe and North America. The causative agent Borrelia burgdorferi sl is a bacterial species complex comprising 12 delineated and named species. In North Africa, few studies based on clinical and serological features, have suggested that LB could occur. Indeed, recent studies conducted in Tunisia, Algeria and Morocco have showm that Ixodes ricinus is present in cooler and humid area of these regions. These studies also revealed that this species is a vector of B. burgdorferi sl with high prevalence of infection. Using IFI and PCR tests, the mean rate of Borrelia-infection ranged from 50 to 60% in I. ricinus adult collected in Tunisia and Morocco and from 30 to 40% in nymphs; in contrast, the prevalence in larvae is less than 2.5%. Several strains of B. burgdorfer were isolated from adult and nymph I ricinus collected in Tunisia and Morocco. The identification of these strains and DNAs directly extracted from Ixodes was done by PCR-RFLP and sequence analysis. The results showed that B. lusitaniae (genotypes Poti B2 and Poti B3) is the predominant species circulating in I. ricinus in Tunisia and Morocco, B. garinii and B. burgdorferi ss and B lusitaniae were also present but very rare. These results provide the evidence for the existence of B. burgdorferi sl in North Africa; however, the impact of LB in the human population seem to be negligible and the seroprevalence of Borrelia in forest workers (considered as population at high risk) in Tunisia is less than 4%.

Africa, Northern↗
PubMed2006

Correlation of tests for detection of Borrelia burgdorferi sensu lato infection in patients with diagnosed borreliosis.

A group of 180 patients with diagnosed Lyme borreliosis were examined for the presence of infection with Borrelia burgdorferi sensu lato (B. burgdorferi s.l.) by serologic tests with B. burgdorferi s.l. antigens (IgM-ELISA, IgG-ELISA, IgM-immunoblot, IgG-immunoblot) and by polymerase chain reaction (PCR, nested-PCR) for detection of B. burgdorferi s.l. DNA in peripheral blood. A total of 61.7 %, 53.9 %, 62.2 %, and 59.4 % of the examined patients' sera showed positive or borderline results in the serologic tests IgM-ELISA, IgG-ELISA, IgM-immunoblot, and IgG immunoblot, respectively. The results of the tests IgM-ELISA and IgM-immunoblot were significantly correlated (p < 0.001). A higher degree of the correlation (p < 0.000001) was found at the comparison of results obtained with IgG-ELISA and IgG-immunoblot. The correlation between the positive findings in the IgM-ELISA and detection with IgM-immunoblot the diagnostically important B. burgdorferi s.l. OspC surface protein was relatively low but statistically significant (0.01 < p < 0.05). Much higher correlation was found between the positive findings in the IgG-ELISA and detection with IgG-immunoblot other diagnostically important B. burgdorferi s.l. antigen, the VlsE protein (p < 0.000001). The presence of B. burgdorferi s.l. DNA was found by PCR in 20 out 180 examined blood samples (11.1 %). No correlation was found to exist between the PCR results and the results of any of the serologic tests for detection of anti B. burgdorferi s.l. antibodies of IgM class. PCR results correlated significantly at a relatively low level (0.01 < p < 0.05) with the results of IgG-ELISA, but not with the results of IgG-immunoblot with regard to total reactions (0.2 < p < 0.1). By contrast, a distinctly significant correlation was found between the PCR results and detection of the VlsE protein with IgG-immunoblot (0.001 < p < 0.01). In conclusion, the results of the present study suggest that antibodies of IgG class are the most reliable marker in laboratory diagnostics of Lyme borreliosis, in particular those directed against VlsE surface protein of Borrelia burgdorferi sensu lato.

Adult↗
PubMed1991

A preliminary study on the function tests of the vibration syndrome in tropical rain forest workers.

Working situations and health hazards directly related to the work of the tropical rain forest workers were studied in Papua New Guinea. The results of the function tests of the vibration syndrome were reported in the preliminary step of this study. Among 61 workers including 16 chain saw operators no clear evidence was found that was related to the health effects of hand-arm vibration, but a possibility existed of an occurrence of subclinical dysfunction of peripheral circulation and peripheral neuropathies. The principal component analysis suggests that the reactiveness of peripheral circulation significantly reflects the duration of the chain saw operation.

Adult↗
PubMed1991

[Relationships between the pollen productions in sugi (Cryptomeria japonica D. Don) forests and the patterns of atmospheric scattering pollens in Toyama Prefecture--the example of Toyama Prefecture in 1990].

We investigated the geographical distribution of sugi (Cryptomeria Japonica D. Don) forests and the male flower-setting conditions of them in Toyama prefecture. The relationships between our findings and the atmospheric pollen scattering patterns were also studied. The results were as follows. 1. Atmospheric pollen counts and their scattering patterns were fairly easily explained by the geographical distribution of 30-year old sugi forests, the male flower-setting conditions and the first day pollen was scattered in those forests. 2. Total atmospheric counts and maximum sugi pollen peaks were significantly affected by the proximity of sugi forests at altitudes of less than 200 meter. 3. In the atmospheric pollen survey, the detected pollen counts decreased according to the distance between the observation sites and the sugi forests. And few pollen grains were observed from natural sugi forests growing at distances of 20 km to 30 km from the observation sites.

Air↗
PubMed1995

The relationship between health status, motivation and work efficiency of forest workers.

The influence of psychological factors on the health status and work efficiency was investigated in a sample of 909 forest workers whose typical diseases had been previously defined. Data concerning the motivation for work were taken during obligatory medical tests. Medical variables (health status, diagnoses, number of diagnoses per worker), psychological variables (job satisfaction, wish to change the job), and work-related variables (fulfillment of job norms) were used. Hypotheses of the relationship between the selected pairs od variables were tested by contingency tables. The lifetime trends of each variable were modelled by means of linear functions. The presumed influence was confirmed by the results obtained. Negative motivation appeared to be a very significant factor of the forest workers' health status and their work efficiency.

Adolescent↗