An ecologically based model of forest succession is presented. In the model, trees compete for a share of limited growth resources available from their environment. Competition is reflected by each tree's effect on the resource pool and is not explicitly modeled. Model parameters were fit to field data from subalpine forests of the Rocky Mountains. A technique for estimating model parameters from understory-tolerance rankings and silvical characteristics of each species is also presented. The model's output was consistent with our current understanding of forest dynamics. Emergent properties of the model also mimicked natural processes such as self-thinning, release, and maximum stand basal area as a function of species present and site quality.

Callous and Unemotional (CU) traits are a relatively recent addition to the existing body of research examining the development of severe behavioural problems in children, and antisocial behaviour in adults. Children who are high in CU traits display shallow emotions, manipulate other children, lie easily, and demonstrate very little remorse or guilt. Additionally, they are more likely to engage in more severe forms of antisocial behaviour, more often, and from a younger age than their peers. Research has found that CU traits moderate the well-established relationship between parenting and conduct problems. That is, children who are high in CU traits seem to display levels of behaviour problems that are unrelated to the quality or type of parenting they receive. This has serious implications when one considers that the most effective psychosocial treatments available for behavioural disorders are based upon improving parenting, and would therefore require significant modification for children high in CU traits. In addition, the research exploring the moderating role of CU traits in the relationship between parenting and conduct problems has not taken a developmental perspective and considered different ages of children. Finally, existing research has not considered the reciprocal relationship that CU traits have upon parenting behaviour, or the direct relationship between parenting and CU traits. The present study has addressed these limitations by utilizing an accelerated longitudinal methodology. The present study recruited 449 grades one, three and five children from six public primary schools. Questionnaires assessing conduct problems, CU traits, and parenting styles were administered to their parents for completion. Additionally, teacher report was also sought on a number of key variables to ensure validity. One year later, all of these children and their families were re-approached to assess the extent to which each of these variables had changed over time. One year later 233 (51.89%) of the original sample completed the same measures allowing examination of the change in these variables over time. Given the relatively short time period, it was expected that one of the best predictors of any of the key variables at time 2, would be baseline scores measured at time 1. For this reason, hierarchical regression was used to control for temporal stability, as well as demographic factors. Additionally, the hypothesis that a different pattern of relationships would emerge for children of different ages was tested by examining the moderating effect of age upon all predictive relationships. This was done by entering the product of age and the predictor variable(s) as the final step of the regression analyses, and then conducting simple slopes analysis on all significant predictive interactions. Three distinct findings emerged from these analyses. Firstly, age moderates the effect of CU traits on the relationship between parenting styles and conduct problems. Behaviour problems in younger children are better predicted by parenting behaviours and by CU traits than in older children. Secondly, both CU traits and conduct problems were predictive of worsening parental behaviour. Once again, this was particularly evident in younger children. Finally, inconsistent parenting, and corporal punishment were found to be predictive of CU traits. These findings are discussed from a developmental perspective in the context of Bronfenbrenner's (1979) ecological model.

School-based physical education is a critical setting for the promotion of physical activity and health among adolescents. However, enrollment in physical education significantly decreases when physical education becomes an optional subject in grade 11, with only 10% of females and 22% of males choosing to enroll. Limited research has identified individual and social environmental perceived barriers to enrollment in elective physical education. Further, no research has explored perceived individual and social environmental facilitators to electing to enroll in physical education. Thus, the purpose of the study was to identify perceived barriers and facilitators to intention to enroll in elective physical education among a diverse group of female and male adolescents using focus group methodology. <p>Two schools were purposely selected to participate in this study, one with the highest enrollment in grade 11 physical education (57%) and one with the lowest enrollment in grade 11 physical education (33%). By selecting schools with the highest and lowest enrollment, comparisons were made between the perceived barriers and facilitators identified by the participants in a school with high enrollment and a school with low enrollment. However, when participant recruitment occurred, no male students at the high enrollment school indicated they did not intend to enroll in grade 11 physical education. In order to attain sufficient participant recruitment within each required group (i.e., male- no intention group) the school with the second highest enrollment in grade 11 physical education (40%) was included within the study. <p>Grade 10 adolescents (N=63) with either an intention to enroll or no intention to enroll in grade 11 physical education participated in a focus group interview. Focus groups were separated based on gender (female/male) and intention to enroll in grade 11 physical education (intention/no intention). Following the completion of the focus group interviews barriers and facilitators were categorized, using McLeroys ecological model, as individual level (e.g., intrapersonal) or social environmental (e.g., interpersonal, institutional, community). <p> Findings revealed several factors that influenced students enrollment intention. However, differences were minimal between factors reported by students in the high and low enrollment schools. Differences were more prominent between gender and intention. These differences between females and males and between participants who were intending to enroll and participants who were not intending to enroll had consistent overarching themes. At the individual level (i.e., intrapersonal) four factors were associated with enrollment intention: past experience, self-efficacy, personal choice: scheduling, and knowledge. Several social environmental factors (interpersonal, institutional, and community) were also reported. These included parents, friends, teammates/coaches, teacher, course curriculum, and activity opportunities within the community.

School climate has been established as an important construct to measure because of its connections to student psychological, social, and academic outcomes. Existing research has examined school climate in relation to individual (i.e., race and gender) and school level (i.e., teacher characteristics or school size) variables. The current paper presents a cultural-ecological model for research on school climate. The cultural-ecological model of school climate supports future research incorporating a broadened view of culture, extending beyond race and ethnicity, and a more comprehensive examination of ecological contexts such as the family and community in understanding student perceptions of school climate. Within this model, individual, family, school, and community variables that may influence student perceptions of school climate are described and a research agenda is presented for utilizing the cultural-ecological model of school climate in future school climate research and for developing, implementing and evaluating strategies designed to enhance school climate and school performance based on prevention and intervention. The current study examined the relationship between cultural and ecological variables at the individual, school, and community levels and student perceptions of school climate. A multi-level (HLM) model examining the relationships between individual, cultural, and ecological variables and school climate was evaluated. Results of the current study indicated that for the relationship between student and school characteristics and school climate remain relatively consistent for both groups. Specifically, both individual and school variables influenced student perceptions of school climate. However, this data also confirms the need to further examine additional cultural and ecological variables in order to increase our understanding of how such variables are related to perceptions of climate.

Social ecological models are recognized for allowing researchers to examine the influence of multiple factors on behaviour, yet to date relatively little research has simultaneously examined the role of personal, social, and environmental factors on youths’ physical activity, while giving consideration to the role of different types of neighbourhoods. The current study examined the physical activity of 804 youth aged 10 to 16 years residing in urban high density, suburban, or suburban low density neighbourhoods, by exploring relationships between several personal, social, and environmental factors. Findings revealed that all three factors were significant in explaining youths’ physical activity. Differences in participation were found based on gender and neighbourhood; males and youth from suburban low density neighbourhoods were significantly more physically active. Moreover, several variables were found to be important for understanding youth physical activity: sex, age, self-efficacy, encouragement, neighbourhood safety, and the use of a number of neighbourhood facilities.

Social ecological models are recognized for allowing researchers to examine the influence of multiple factors on behaviour, yet to date relatively little research has simultaneously examined the role of personal, social, and environmental factors on youths’ physical activity, while giving consideration to the role of different types of neighbourhoods. The current study examined the physical activity of 804 youth aged 10 to 16 years residing in urban high density, suburban, or suburban low density neighbourhoods, by exploring relationships between several personal, social, and environmental factors. Findings revealed that all three factors were significant in explaining youths’ physical activity. Differences in participation were found based on gender and neighbourhood; males and youth from suburban low density neighbourhoods were significantly more physically active. Moreover, several variables were found to be important for understanding youth physical activity: sex, age, self-efficacy, encouragement, neighbourhood safety, and the use of a number of neighbourhood facilities.

School-based physical education is a critical setting for the promotion of physical activity and health among adolescents. However, enrollment in physical education significantly decreases when physical education becomes an optional subject in grade 11, with only 10% of females and 22% of males choosing to enroll. Limited research has identified individual and social environmental perceived barriers to enrollment in elective physical education. Further, no research has explored perceived individual and social environmental facilitators to electing to enroll in physical education. Thus, the purpose of the study was to identify perceived barriers and facilitators to intention to enroll in elective physical education among a diverse group of female and male adolescents using focus group methodology. <p>Two schools were purposely selected to participate in this study, one with the highest enrollment in grade 11 physical education (57%) and one with the lowest enrollment in grade 11 physical education (33%). By selecting schools with the highest and lowest enrollment, comparisons were made between the perceived barriers and facilitators identified by the participants in a school with high enrollment and a school with low enrollment. However, when participant recruitment occurred, no male students at the high enrollment school indicated they did not intend to enroll in grade 11 physical education. In order to attain sufficient participant recruitment within each required group (i.e., male- no intention group) the school with the second highest enrollment in grade 11 physical education (40%) was included within the study. <p>Grade 10 adolescents (N=63) with either an intention to enroll or no intention to enroll in grade 11 physical education participated in a focus group interview. Focus groups were separated based on gender (female/male) and intention to enroll in grade 11 physical education (intention/no intention). Following the completion of the focus group interviews barriers and facilitators were categorized, using McLeroys ecological model, as individual level (e.g., intrapersonal) or social environmental (e.g., interpersonal, institutional, community). <p> Findings revealed several factors that influenced students enrollment intention. However, differences were minimal between factors reported by students in the high and low enrollment schools. Differences were more prominent between gender and intention. These differences between females and males and between participants who were intending to enroll and participants who were not intending to enroll had consistent overarching themes. At the individual level (i.e., intrapersonal) four factors were associated with enrollment intention: past experience, self-efficacy, personal choice: scheduling, and knowledge. Several social environmental factors (interpersonal, institutional, and community) were also reported. These included parents, friends, teammates/coaches, teacher, course curriculum, and activity opportunities within the community.

An ecosystem always involves some implicit relations between habitat environment and inhabitants, whose reciprocal links can not be identified easily. Three sets of ecological monitoring data were analyzed in this study, including coral reef, algae (Thalassia hemprichii Aschers) in Kenting National Park, and Formosan landlocked salmon (Oncorhynchus masou formosanus) in the basin of Chichiawan Stream. Two data-oriented analysis techniques, which are Habitat Evaluation Procedure (HEP) and Group Method of Data Handling (GMDH), were applied to retrieve the embedded patterns from these data sets. Eventually, for each data set, a forecasting model based on the technique of combined forecasting were developed, which is to integrate the results from HEP and GMDH, for improving the overall modeling precision. The results of this study show that the data-oriented analyses, such as HEP and GMDH, are useful for finding valid information from the ecological data. Furthermore, the combined forecasting technique can really improve the performance of model prediction even for the ecological research. In order to acquire the most important habitat environmental factors affecting the inhabitants, this study also performed sensitivity analysis of the models. The contributions of this study are to identify effective knowledge for future ecological research and to provide reasonable suggestions for formulating conservation strategy.

Domestic violence is a global issue, and despite awareness of the issue increasing, the prevalence to which women are being physically and mentally abused is increasing. This study aimed to qualitatively investigate the impact of cultural barriers on the provision of aid to victims of abuse from the perspectives of social workers within a domestic violence care organisation in Kuala Lumpur, Malaysia. Social workers within the organisation were interviewed to examine their personal experiences of working with clients from different cultural backgrounds and the results were analysed using the ecological model and the intersectional theory, as well as using earlier research conducted on the issue. The findings showed that the culture of a client can have an effect with regards to abused women seeking help, though the practices of the organisation were generally not impacted based on the cultural background of a client.

School climate has been established as an important construct to measure because of its connections to student psychological, social, and academic outcomes. Existing research has examined school climate in relation to individual (i.e., race and gender) and school level (i.e., teacher characteristics or school size) variables. The current paper presents a cultural-ecological model for research on school climate. The cultural-ecological model of school climate supports future research incorporating a broadened view of culture, extending beyond race and ethnicity, and a more comprehensive examination of ecological contexts such as the family and community in understanding student perceptions of school climate. Within this model, individual, family, school, and community variables that may influence student perceptions of school climate are described and a research agenda is presented for utilizing the cultural-ecological model of school climate in future school climate research and for developing, implementing and evaluating strategies designed to enhance school climate and school performance based on prevention and intervention. The current study examined the relationship between cultural and ecological variables at the individual, school, and community levels and student perceptions of school climate. A multi-level (HLM) model examining the relationships between individual, cultural, and ecological variables and school climate was evaluated. Results of the current study indicated that for the relationship between student and school characteristics and school climate remain relatively consistent for both groups. Specifically, both individual and school variables influenced student perceptions of school climate. However, this data also confirms the need to further examine additional cultural and ecological variables in order to increase our understanding of how such variables are related to perceptions of climate.