In the study of ecological community structure, the multivariate niche model has always been the assumed structural model. This model is closely connected to the multivariate two-sample problem. Important to the understanding of species interactions in a community is the measurement of the degree to which the niches of two species overlap, or to measure the similarity between the resource use distributions of the species. Discriminant analysis is the tool used most often to analyze the similarity. In this study, we discuss the most commonly used similarity measures, and develop measures that are less dependent on the assumptions of the usual discriminant analysis. Specifically measures arc derived assuming normal distributions with heterogeneous variance-covariance matrices arc derived. The problem of estimating the measures and their precision and accuracy is investigated. Two methods, the jackknife and the bootstrap, arc described for estimating the bias and variance of an estimated measure. The performance of these methods was evaluated using simulation. When the number of variables involved in the model is large, the estimates of these measures may be severely biased, and the bias is consistently negative. By collecting larger samples the bias can be reasonably adjusted. Two potentially important factors affecting results arc the disparity in the means and the heterogeneity of the variance-covariance matrices. It is shown that when the mean separation is small, the heterogeneity of the covariance matrices has a moderate effect on the bias, but the effect is diminished when the mean separation becomes larger. The variance of the similarity estimates is also related to the value of the measure and is a quadratic function of the similarity. The logarithmic transformation of the similarity is seen to linearize the variance of the similarity estimate. The jackknife method gives good adjustment of the bias of the estimated measures. Generally, the bootstrap method performs worse than the jackknife method. In some cases, especially when there are many redundant variables neither method gives reliable results. / Ph. D.

Yu Chi Cheung. / Thesis submitted in: August 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 156-169). / Abstracts in English and Chinese. / Abstract / Declaration --- p.i / Acknowledgement --- p.ii / Contents --- p.iv / List of Figures --- p.vi / List of Tables --- p.vii / List of Plates --- p.x / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- About Hong Kong --- p.2 / Chapter 1.1.1 --- Geography --- p.2 / Chapter 1.1.2 --- Climate --- p.4 / Chapter 1.1.3 --- Vegetation --- p.7 / Chapter 1.1.4 --- Wildlife conservation in Hong Kong --- p.10 / Chapter 1.2 --- Land Restoration --- p.12 / Chapter 1.2.1 --- General processes of restoration --- p.13 / Chapter 1.2.2 --- Plantation in Hong Kong quarries --- p.15 / Chapter 1.2.3 --- Ecological succession in Hong Kong --- p.16 / Chapter 1.2.4 --- Problems in quarry restoration --- p.17 / Chapter 1.3 --- Objectives --- p.18 / Chapter 1.3.1 --- Study sites --- p.18 / Chapter 1.3.2 --- Soil-plant ecosystem --- p.27 / Chapter 1.3.3 --- Insect study --- p.28 / Chapter 1.3.4 --- Lepidopteran as a study group --- p.29 / Chapter 1.3.5 --- Odonata as a study group --- p.31 / Chapter 1.4 --- Project Significant --- p.32 / Chapter Chapter 2 --- Soil Status in Restored Quarries in Hong Kong --- p.35 / Chapter 2.1 --- Introduction --- p.35 / Chapter 2.2 --- Materials and Methods --- p.37 / Chapter 2.2.1 --- Soil sampling --- p.37 / Chapter 2.2.2 --- Soil analysis --- p.37 / Chapter 2.3 --- Statistical Analysis --- p.39 / Chapter 2.4 --- Results and Discussion --- p.39 / Chapter 2.4.1 --- General properties of soil in the restored quarries --- p.39 / Chapter 2.4.2 --- Soil description on different phases among the sites --- p.43 / Chapter 2.4.3 --- Soil comparison on different phases with the same age --- p.45 / Chapter 2.5 --- Conclusion --- p.47 / Chapter Chapter 3 --- Vegetation Study of Restored Quarries --- p.49 / Chapter 3.1 --- Introduction --- p.49 / Chapter 3.2 --- Materials and Methods --- p.52 / Chapter 3.2.1 --- Vegetation survey --- p.52 / Chapter 3.2.2 --- Quadrat analysis --- p.53 / Chapter 3.2.3 --- Vegetation description --- p.53 / Chapter 3.2.3.1 --- Similarity index --- p.53 / Chapter 3.2.3.2 --- Species richness index --- p.53 / Chapter 3.2.3.3 --- Diversity index --- p.54 / Chapter 3.2.3.4 --- Evenness index --- p.54 / Chapter 3.2.3.5 --- Effective number of species --- p.54 / Chapter 3.3 --- Results and Discussion --- p.55 / Chapter 3.3.1 --- Vegetation coverage on restored quarries --- p.55 / Chapter 3.3.2 --- Vegetation structure and diversity on restored quarries --- p.58 / Chapter 3.3.3 --- Ecological indices on various sites --- p.78 / Chapter 3.3.4 --- Successful plants at various phases among the sites --- p.80 / Chapter 3.3.5 --- "Tree vs shrubs, native vs exotic" --- p.85 / Chapter 3.4 --- Conclusion --- p.87 / Chapter Chapter 4 --- Butterfly Communities on Restored Quarries --- p.89 / Chapter 4.1 --- Introduction --- p.89 / Chapter 4.2 --- Materials and Methods --- p.90 / Chapter 4.2.1 --- Pollard-walk method --- p.90 / Chapter 4.2.2 --- Statistical analysis --- p.95 / Chapter 4.3 --- Results and Discussion --- p.95 / Chapter 4.3.1 --- General description of the butterfly communities --- p.95 / Chapter 4.3.2 --- Uncommon species found on the quarries --- p.99 / Chapter 4.3.3 --- Butterfly species found on various phases of the sites --- p.102 / Chapter 4.3.4 --- Ecological indices on various sites --- p.114 / Chapter 4.4 --- Conclusions --- p.117 / Chapter Chapter 5 --- Moth Communities on Restored Quarries --- p.118 / Chapter 5.1 --- Introduction --- p.118 / Chapter 5 2 --- Materials and Methods --- p.119 / Chapter 5.2.1 --- Light trapping method --- p.119 / Chapter 5.3 --- Results and Discussion --- p.120 / Chapter 5.3.1 --- General description of moth community --- p.120 / Chapter 5.3.2 --- Ecological indices of moth on various sites --- p.123 / Chapter 5.3.3 --- Moth species found on various phases of the sites --- p.129 / Chapter 5.3.4 --- Ecological importance of Lepidopterans --- p.142 / Chapter 4.4 --- Conclusion --- p.143 / Chapter Chapter 6 --- General Conclusion --- p.145 / Chapter 6.1 --- Soil Development and Species Diversity --- p.145 / Chapter 6.2 --- Current Status of Restored Quarries in Hong Kong --- p.148 / Chapter 6.3 --- Conservation Value of Restored Quarries --- p.150 / Chapter 6.4 --- Limitation of the study --- p.151 / Chapter 6.4.1 --- Light trap --- p.151 / Chapter 6.4.2 --- Correlation vs causation --- p.153 / Chapter 6.5 --- Area for Further Investigation --- p.154 / Chapter 6.4.1 --- Seed bank analysis --- p.154 / Chapter 6.4.2 --- Other inventories --- p.154 / References --- p.156 / Appendix Odonate Communities on Restored Quarries --- p.170 / Introduction --- p.170 / Materials and Methods --- p.172 / Visual encounter survey --- p.172 / Statistical analysis --- p.172 / Results and Discussion --- p.173 / General description of odonate community --- p.173 / Ecological indices of odonate on various sites --- p.175 / Odonates species on various phases of the sites --- p.179 / Conclusion --- p.183 / References --- p.184

Thesis (M.S.)--Mississippi State University. Department of Agricultural and Biological Engineering. / Title from title screen. Includes bibliographical references.

By Walter S. Phillips from Homer L. Shantz' records and negatives. / Contract: Office of Naval Research / Nonr-2173 (01) / Project NR 387-018

This research project develops a theoretical approach to the study of the experience of environmental quality. The approach is derived from the transactional perspective of perception and uses the concepts of mergence and barriers to explain how people's experience of a place relates to their judgment of environmental quality. It assumes that people value environments which facilitate positive emotional experiences and that the judgment of environmental quality is related to the potentialities of the environment to provide a context for valued experiences. The implications of this theory are discussed with regard to the differences between the experience of built versus natural environments, an experiential versus value system approach to environmental quality, and the value of high quality natural environments. The first study used a structured interview to examine people's experience and evaluation of high and low quality built and natural environments in the Tucson area. The second study examined the use of photographic surrogates for the study of environmental quality by comparing objective photographs with subjective photographs taken by people visiting environments. The results support the view that the human valuing process is an affective, synthesizing, and concretizing process. The experiential differences between built and natural environments were examined with regard to the degree of interrelatedness of the physical, social, and functional aspects of the environment. The experiential and value system approaches to studying environmental quality were shown to be complementary, and some potential problems with the value system approach were examined. The value of high quality natural environments was shown to relate to the symbolic, spiritual and experiential meaning which people attribute to them. Although there were differences between the two methods of photographically simulating environments, both methods were shown to be useful for providing surrogates for the study of environmental quality. Overall, this research demonstrated the value of a holistic experiential framework for the study of environmental quality which helps to unite scientific research with people's experience of the environment.

Studies were conducted on the dynamics of live, standing recent dead, and standing old dead herbage for a desert grassland site in the southwestern United States. Data were collected at eleven sample dates from August 24, 1979 to October 18, 1980. Coefficients of variation for biomass data for most species exceeded 400% with only the most abundant species sampled with coefficients of variation less than 100%. Coefficients of variation generally were less than 80% for the perennial grasses as a group. The mean rate of transfer of biomass from live herbage to standing recent dead herbage was 0.21% per day for 203 days when expressed as a percentage of the peak live herbage. A rate of transfer of 0.53% per day of live herbage to standing dead for 109 days for perennial grasses in the desert grassland was found during early vegetative growth. A high proportion of leaves to culms was present during this period as compared to the summer growing season. Heavy precipitation in the early part of September accelerated growth of live herbage, and also accounted for losses of standing recent dead and standing old dead herbage to the surface litter component. The loss of dry leaves from standing grass culms due to rainfall impact contributes to an underestimate of net primary production. Standing old dead biomass accumulated following the depression in September. Transformation of the recent dead herbage to an appearance of old dead late in the summer also contributed to underestimating of current year production based on peak crop method due to the identification of recent dead herbage as the old dead component. Summation of growth increments by sample periods provided the highest estimate of aboveground net primary productivity when compared to estimates based on peak standing crop, summation of species peaks, and summation of significant growth increments by sample periods. Estimates of net productivity were 186% of the estimate at peak standing crop. Estimates of net production based on significant growth increments by sample periods yield the lowest value for net production, because poor precision of samples restricted data to few significant values. Based on the peak periods for standing biomass of lifeform groups, a minimum of four sample dates are recommended to estimate aboveground net primary production for semidesert grassland in southeastern Arizona. These sample dates include: (1) late April to sample spring peaks by perennial grasses, annual forbs and annual grasses; (2) late June to capture the spring trough; (3) late September to sample peak crops of perennial forbs, and half-shrubs; and (4) mid to late October to sample the fall peak for perennial grasses. Net production estimates by the peak crop method for perennial grasses varied from 18.7 g/m² in 1979 to 86.1 g/m² in 1980. This variability was attributed to the differences in the amount of rainfall in 1979 and 1980. This factor, therefore, largely influenced the repeatability of biomass estimates from one year to another. The large amount of time (approximately 644 man-hours) needed to sample and separate live and dead components by species for 20 quadrats at each harvest date, together with the year-to-year variability and the need for a minimum of four sample dates to effectively sample the desert grassland community, makes biomass data impractical for general use as a data base in land-use planning. However, this effort should be looked at from the standpoint of research studies describing the dynamics of range systems based on temporal characteristics and transfer functions to provide data which can help design management strategies for these range ecosystems.

Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Soil and Land Systems, 2004. / "April 2004" Includes bibliographical references (leaves 308-327).

Theory of ecological (biophysical) land classification is presented. The theory of integrated ecological land classification, mapping and analysis is applied to recreational land planning. An approach to recreational site-suitability analysis appropriate for reconnaissance level inventories and analyses of recreation capabilities is presented. Clague Mountain Park, Kitimat, B.C. served as a case study for applying the recreation site-suitability analysis approach developed. Landforms, identified using the Terrain Classification System (Ministry of Environment, 1978), served as the basis upon which selected ecologically-significant parameters were inventoried and analyzed. The parameters used in this analysis included topography, depth to bedrock, frost action, flood hazard, vegetation, climate and various soil characteristics, including moisture regime, texture, stoniness, rockiness, permeability and erosion hazard. The activities considered in this analysis included camping (intensive), hiking (summer), picnicking/day use, cross-country skiing, downhill skiing, mountain climbing/mountaineering, toboggan-ning, snowmobiling and snowshoeing. The recreational suitability of the park was summarized in tables and maps. It was found that this site-suitability analysis approach provided an effective means for establishing an area's recreational suitability. It is recommended that the findings of this analysis be used to assist in any future recreation planning and management within the park. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

No description available.

This study is an interdisciplinary ecological study addressing the fine-scale relationships between plants, invertebrates and the environment in an alpine ecosystem. Alpine environments are marked by steep environmental gradients and complex habitat mosaics at various spatial scales. Regular forming periglacial patterned ground landforms on the Old Man Range, Central Otago, South Island, New Zealand present an ideal medium for studying plant-invertebrate-environment relationships due to their partitioning of the landscape into discrete units of contrasting environmental conditions, and the existence of some baseline knowledge of the soil, microclimate, vegetation and flora. The study was conducted in three types of patterned ground (hummocks, stripes and solifluction terraces) on the Old Man Range. Each component of the study was sampled at the same spatial scale for comparison. Temperature was recorded in the soil and ground surface from April 2001 to March 2004 in microtopographic subunits (microsites) of each patterned ground landform. Plant species cover was sampled within each microsite; invertebrates were sampled from soil cores taken from the same locations as plant samples in April 2001 and September 2001. The two sampling occasions coincided with autumn before the soil freezes, and winter when maximum freezing was expected. Fine-scale changes in the topographic relief of the patterned ground led to notable differences in the timing and duration of snow. The steepest environmental gradients existed during periods of uneven snow distribution. The soil in exposed or south-facing microsites froze first, beginning in May, and typically froze to more than 40cm depth. Least exposed microsites rarely froze. Within the microtopography, patterns of freezing at specific locations were consistent between years with only minor differences in the timing or depths of freezing; however, notable variation in freezing existed between similar microsites. Within the microtopography, different assemblages of organisms were associated with different microsites. In total, 84 plant and lichen species were recorded, grouping into six community types. Species composition was best explained by growing degree-days, freeze-thaw cycles, time frozen and snow-free days; species diversity and richness increased with increasing environmental stress as indicated by freeze-thaw cycles, time frozen and exposure. In total 20,494 invertebrates, representing four Phyla, 12 Classes, 23 Orders and 295 morpho-taxa were collected from 0.17m� of soil. Acari, Collembola and Pseudococcidae were the most abundant invertebrates. Over 95% of the invertebrates were found in the plant material and first 10cm depth of soil. Few significant relationships were found between diversity, richness or abundance of invertebrate taxa and the microsites; however, multivariate analyses identified distinct invertebrate assemblages based on abundance. Invertebrate composition was best explained by recent low temperature and moisture, particularly in winter; however, plant composition also explained invertebrate composition, but more so in autumn. This research has shown that organisms in the alpine environment of the Old Man Range are sensitive to fine-scale changes in their environment. These results have implications as to how historical changes to the ecosystem may have had long-lasting influences on the biota, as well as how a currently changing climate may have further impacts on the composition and distribution of organisms.