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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Parkia biglobosa (Jasq.) benth. in Nigeria : a resource assessment

Oni, Peter I. January 1997 (has links)
Parkid higlohosa, an important indigenous fruit tree of West Affican Sudanian woodland, was studied with respect to natural population distribution and structure, regeneration, reproductive biology and phytosociology in Nigeria. As relevant background, a comprehensive range-wide monographic account of the species was assembled. An ecological survey covering the range of Parkia in Nigeria was undertaken between 1994-1995. The survey involved four ecological zones ranging from derived to Sudan/Sahel zone transition. In each ecological zone there were two sample sites within each of which there were two land use types. The survey showed that nearest mature con-specific neighbour distance and corresponding stocking for all individuals ý: 10 cm dbh ranged from 25.5 m and 15 tree ha-I in the north down to 91.5 m and I tree ha-I in the south. A gradual increase in stocking from the lowland forest zone boundary to the Sudan savanna was observed. Parkia populations are significantly more concentrated in cultivated fields than in less intensively used areas of the bush fallow. Natural regeneration in Parkia in Nigeria was sparse overall - 9.80 individuals ha-I and coppice shoot regeneration was the main form. Bush fallow conditions favour more regeneration than intense cultivation, and to the south there is more regeneration than in the north. Tree morphological appraisal showed that there tended to be taller trees in the south of the Nigerian range (with a moister climate) but with smaller diameter than in the north. A broader crown diameter typified populations in the northern part of Nigeria range compared with the south. Branching height ranged from 1.7 m in the north to 3.9 m in the south. The tree rarely branched below Im anywhere. Two was the most frequent number of primary branches. Individuals with more than two primary branches per tree occur more frequently in the north of the range. For all morphological parameters except the number of primary branches a significant land use effect was detected. In the survey 136 associated woody species were recorded. More woody tree species were associated with Parkia biglobosa in the south than in the north of its range in Nigeria. A reproductive cycle of 135 days was observed at Saki, Nigeria. Capitulum abortion rate was more than 30% and not related to the tree diameter or crown position. Capitulum, podding efficiency was about 67%. Open pollinated capitula had the highest number of pods per treatment. Parkid displays some degree of self-compatibility. Capitula located >5 m above the ground are more likely to be pollinated than those below.
342

The structural root systems of Sitka spruce and related stochastic processes

Henderson, Robin January 1981 (has links)
No description available.
343

Upgrading forestry training : three areas for development in Indonesia

Ruhandi, Aep January 1998 (has links)
This study reviews the upgrading of forestry training in Indonesia comprising public, private and local people. The principal aim of this study is to investigate if, and how, forestry training can meet the needs of Indonesia forestry sector as methods of sustainable forest management are developed. Sustainability of forest resources and its underpinning by human resource development systems and processes are currently the primary issues and serious challenges for Indonesia forestry sector. The current capacity of forestry training in Indonesia is considered inadequate to meet the challenge. Forestry training managers and trainers in both public and private sectors, timber company managers and workers, and local people were involved in the human resource development processes to meet the new requirements and to see through the remaining traditional forestry training at the same time. Consideration was given to the weakness of the capacity of the current forestry training and the needs for improvement. The literature review took a theme approach covering the fields of human resource development processes, training and development, the six Indonesia five - year development plans, the guidelines for sustainable forest management of Indonesia and the International Tropical Timber Organisation. The main focus for obtaining data with respect to the respondents and informants was the changes brought about by training. The methodology centred on the design and use of a questionnaire with return rate of 55% from eighty managers of forest concessions, 80% from ten heads of public forestry training centres and 60% from eight private forestry training centres. In addition, a formal interview was conducted with HPH managers, APHI representatives, Forestry officials, local government, and trainers. Semi - structured interviews were conducted with villagers and HPH workers. Observations were conducted of villages within KPHP pilots in Riau, Jambi, Central Kalimantan, and East Kalimantan concerned with Forest Village Development. Teaching sessions of trainers graduated from OTTA at the Wolverhampton University were also observed. These data formed the basis of an analysis of the gap between the ideal future forestry human resource capacity and the current provision in relation to sustainable forest management. Analyses of quantitative data were conducted based on descriptive statistics using Excel. The approach to qualitative data was from open to axial and selective coding. In this study the limitation of upgrading forestry training emerged. This limitation is also endorsed by the users of the training programmes. The forestry extension activities are seen as an integral part of human resource development processes and as such must be with the respect to the forestry training programmes. The sustainable forest management can be justifiably incorporated within the upgrading forestry training. The only high standard of forestry training that can assure a success of forestry development is by providing welltrained foresters. Training has to become a strategic preoccupation of senior executives and top trainers as agent of change, which induces positive work attitudes, commitment, discipline and professionalism.
344

Population dynamics of tropical forest trees

Manokaran, N. January 1988 (has links)
Tree population dynamics were monitored in three tropical rain forest sites in Peninsular Malaysia. The studies involved trees ≥ 10 cm dbh, over 36 years in hill dipterocarp forest at Bukit Lagong, and over 38 and 13 years in lowland dipterocarp forests at Sungei Menyala and Pasoh respectively. Trees were periodically measured for dbh, and mortality and recruitment recorded. Sapling populations at Sungei Menyala were also enumerated at periods separated by about 30 years. The major findings were: decline in tree density over the periods of study were offset by incremental growth in surviving trees, showing that the forests are fully stocked and structurally stable; mortality rates and 'half-life' values were 2.03%, 2.07% and 1.39% yr^-1, and 34.2, 33.5 and 49.9 years for Sungei Menyala, Pasoh and Bukit Lagong respectively; mortality was not correlated with size class for the lowland forests, but there was some evidence for higher mortality in the larger size classes for the hill forest, this possibly being related to soil instability on steep slopes; the risk of death was about 7-8 times greater for trees with negative or no growth, with suppression leading to higher mortality in canopy than in understorey species; recruitment rates to the 10 cm dbh class were 1.32%, 1.46% and 0.85% yr^-1 at Sungei Menyala, Pasoh and Bukit Lagong respectively; dbh increments were linear over long periods for most trees, future size of individuals therefore predictable from one set of measurements; fast-growing mature trees are estimated to be as young as 60 years; variation in species composition over time was slight compared with variation between sites; sapling composition and density at Sungei Menyala changed greatly over 30 years but that for adults remained constant over 38 years, showing that future canopy composition is unlikely to change without catastrophic disturbances occurring.
345

A forest polity in western India : the Dangs; 1800s-1920s

Skaria, Ajay January 1992 (has links)
No description available.
346

Tree population history in the Flandrian of East Anglia

Bennett, K. D. January 1982 (has links)
No description available.
347

Wood structures in relation to external growth characteristics in conifers

Handley, A. January 1980 (has links)
No description available.
348

Fungal colonisation of extraction wounds in conifers

El-Atta, Hashim Ali January 1984 (has links)
No description available.
349

A decision support system for multi-objective forest management : a study in the Queen Elizabeth National Forest Park in Scotland

Kazana, Vasiliki January 1989 (has links)
No description available.
350

The value of remote sensing in forest surveys

Pakarian, Ali Asghar January 1982 (has links)
No description available.

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