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Tropical forests : climate variability, vegetation productivity and human disturbance= Bosques tropicales: variabilidad climática, productividad de la vegetación y perturbación humana
Get PDFLos objetivos de esta tesis son:
i. Evaluar la realización del mapeado de la imagen MODIS de los diferentes usos/cobertura de suelos de la Reserva del bosque Pasoh (península de Malasia) utilizando el método de clasificación de no supervisión.
ii. Desarrollar el sistema de evaluación y clasificación de la sequía en Malasia suroeste durante la estación del monzón en una zona propensa a la sequía usando los datos del satélite recogidos del MODIS.
iii. Evaluar la perturbación humana en NNPP y desarrollar un mapa de apropiación humana NPP usando el criterio de la actividad humana.
iv. Comparar el impacto de crecimiento de la población humana en los dos bosques tropicales de Malasia y Tailandia.
Los bosques tropicales desempeñan un papel importante para mantener el ambiente y mitigar el calentamiento global del planeta. Al mismo tiempo, la agricultura es crítica para soportar tanto la vida humana como la mayor parte de la economía de los países asiáticos del suroeste, especialmente en Malasia. Esta tesis presenta los factores más destacables que contribuyen en las perturbaciones de los bosques tropicales y el desarrollo de la agricultura en la región, y desarrolla un sistema de modelado de bajos costes que se podrían usar para evaluar los impactos humanos en la Producción Primaria Neta (PPN). El estudio ayudará a entender mejor las consecuencias de las perturbaciones humanas, incluyendo el crecimiento de la población y los cambios climáticos, y de modo especial las sequía en los bosques y en las tierras de agricultura en el suroeste de Asia. Por ello se usa las imágenes de resolución moderada MODIS junto con otros datos públicos disponibles para desarrollar este modelo. La tesis identifica los tres factores más cruciales: la variabilidad del clima, la productividad de la vegetación y las perturbaciones humanas, incluyendo el crecimiento de la población. Este crecimiento poblacional es la causa de la mayor parte de los problemas ambientales de los bosques tropicales, y por lo tanto facilitar orientaciones que puedan ayudar para el buen desarrollo de la Política Nacional de los Bosques y de la Biodiversidad.
El capítulo 1 introduce la metodología de análisis de imágenes de MODIS para el desarrollo de los modelos SIG, así como la clasificación de las capas de información de los usos del suelo. El capítulo 1 se basa en la viabilidad del uso de las imágenes MODIS combinado con el uso del suelo, los mapas topográficos y las imágenes de ALOS que sirve para clasificar las capas de uso del suelo. Particularmente para la resolución de mapas de los bosques naturales y las plantaciones.
El capítulo 2 enfoca los cambios de la vegetación en los bosques naturales y las plantaciones sometidos a las condiciones de la sequía. Este capÍtulo desarrolla el monzón del suroeste de Malasia (M-SWM) sometido a las condiciones de la sequía usando los índices de de la Malasia Peninsular.
En el capítulo 3 se valora el impacto de las actividades humanas en estas áreas en producción primaria neta (conocido como HNPP). El capitulo3 enfoca el impacto de la actividad humana en la producción primaria neta que clasifica los niveles del impacto humano en las zonas forestales.
El capítulo 4 evalúa el consumo de la producción primaria neta per cápita, los recursos de extracción de los bosques y la contaminación que provienen de la actividad agricultura en dos bosques tropicales del suroeste de Asia situados en Malasia y Tailandia. El capítulo 4 compara el impacto de la proyeccion del crecimiento de la poblacion en el NPP, la extraccion de los recursos forestales y la contaminación en los bosques de Malasia y Tailandia en los proximos 30 años.
Abstract
The aims of this thesis are:
i. To assess the performance of MODIS imaging for mapping different land uses/covers in the Pasoh Forest Reserve, Peninsular Malaysia using unsupervised classification methods .
ii. To develop a classification system for drought assessment for the Malaysia Southwest Monsoon season, in a drought-prone area using satellite image data from MODIS.
iii. To assess human disturbance impacts on NPP and to develop maps of human appropriation of NPP using human activity criteria (Chapter 3).
iv. To compare human population growth impacts on two tropical forests, one in Malaysia and one in Thailand.
Tropical forests play an important role in maintaining the environment and mitigating global warming. At the same time, agriculture is critical to support human life as well as a major part of the economy in Southeast Asian countries, particularly Malaysia. This thesis presents the major factors contributing to disturbances in tropical forests and agricultural land in the region, and develops a low-cost modeling system that can be used to assess human impacts on Net Primary Productivity (NPP). The study will assist in better understanding and appreciating the consequences of human disturbances, including population growth and climate change, particularly drought to the forests and agricultural lands in Southeast Asia. Moderate resolution MODIS image along with other publicly available data, are employed to develop this model. The thesis identifies the three most crucial factors: climate variability, vegetation productivity and human disturbance including population growth that cause most of the problems in tropical forests, hence providing insights that can be helpful in developing effective national forest and biodiversity policies.
Chapter 1 introduces the method of using MODIS image for developing land use/land cover classification maps. Chapter 2 focuses on monitoring vegetation in natural forests and plantations under drought conditions. Chapter 3 assesses the impact of human activities in these areas, on net primary productivity (known as HANPP), and Chapter 4 to assess net primary productivity consumption per capita, forest resource extraction and pollution from agricultural activity in two tropical forests of Southeast Asia, one in Malaysia and one in Thailand. Chapter 1 assesses the feasibility of using MODIS images, combined with land use and topographical maps and ALOS imaging, for classifying land cover for the study area, particularly for mapping natural forests and plantations. Chapter 2 develops the Malaysia Southwest Monsoon (M-SWM) drought classification using MODIS indices for Peninsular Malaysia. Chapter 3 provides an assessment of human activity impact on net primary productivity that rating human impact levels for forest areas. Chapter 4 compares projected human population growth impacts on NPP, forest resource extraction and pollution on Malaysian and Thai forests, for the next 30 years
Forest Fire Hazard Rating Assessment In Peat Swamp Forest Using Integrated Remote Sensing And Geographical Information System
Get PDFForest fire can be a real disaster, regardless of their causes, be it human activity or nature. While it is difficult to control nature, it is possible to map different hazard levels thereby minimizing fire hazards and avoid potential damage. Satellite data plays an important role in detecting and mapping forest fires, involving different types of vegetation. This study was conducted with two objectives: first by applying remote sensing techniques to delineate fuel types map and burnt areas in peat swamp forest; secondly was to develop a fire hazard modelling and mapping of fire hazard rating areas using the Geographical Information System (GIS).
A fire prone peat swamp forest located in Penor, Pahang was selected for the study. A colour composite image from Landsat Thematic Mapper (TM) was transformed using Tasseled Cap Transformation (TC) and a fuel types map was produced. Roads and canal were digitized and developed as layers using ArcGIS 8.2. These layers were composite and four categories of forest fire hazard ranging from extreme to null were automatically derived. The final forest fire hazard rating map is presented in ArcView 3.1.
In conclusion, almost 50% of the study areas were classified as ‘low’ hazard and only 10% of the areas were classified as ‘extreme’ hazard. As a result, the fire hazard map can be used for better forest fire management activities for that area
Interactions between water, soil and forest health in lowland tropical forests
No full textThe severe drought that hit Malaysia was caused by the El-Niño Southern Oscillation (ENSO). Studies have shown that tropical forests depend heavily on evapotranspiration during the dry season, which is influenced by factors such as rainfall quantity and vapour pressure deficit (VPD). The objective of this research is to investigate the interaction between soil, water and forest health by measuring water content and evapotranspiration. The research aimed to understand how the forest ecosystem responds to severe dryness by monitoring soil water content and evapotranspiration, comparing them to rainfall and VPD during the research period. Forest health was determined by satellite indices such as the Normalized Difference Vegetation Index (NDVI) and soil moisture index (SMI). The study took place at the Pasoh Forest Reserve (FR) in Jelebu, which has the lowest annual rainfall, making it an ideal location to study the potential effects of climate change on the forest ecosystem. The results revealed that the forest's evapotranspiration uses a significant amount of rainfall in Pasoh, while less than 10 helps replenish the soil's water content. Due to the high intensity and brief duration of rainfall, between 20 and 45 of it contributes to surface runoff. Despite a consistent VSWC pattern throughout the observation period, the observation in 2019 and 2020 demonstrates that the forest in Pasoh FR responded favourably to the amount of rainfall. Several dry spells with very low monthly rainfall (less than 60 mm per month) were recorded in 2019. February 2019 was one of the driest months on record, with only 3.56 mm of rain falling. January 2022 was also classified as dry, with less than 60 mm of monthly rainfall. The publication of these findings has significantly enhanced and updated forest hydrology information in this region. This information is vital for improving research ideas and can be utilized for climate change mitigation plans. Understanding how soil moisture and evapotranspiration react to dry conditions in tropical forests is crucial research. It provides valuable insights into the ecosystems' vulnerability to climate change, which can inform adaptive management strategies and ensure long-term resilience and sustainability
Defining fire issues in Malaysia and Indonesia through recent satellite technology: a review on MODIS fire detection and burned mapping
Get PDFForest fire, a global phenomenon, often leads to environmental degradation such as habitat damage and
trans-boundary haze. In response to growing concerns over the burning of peat swamp forests, researchers have begun developing methods of detecting and mapping forest fire. In addition, substantial progress has been made in forest planning and fire management, as well as in developing fire detection method using modeling techniques. This paper reviews current forest fire detection and burned area mapping methods that have been applied and studied in most affected area in Malaysia and Indonesia. This paper is also
discussing other methods of remote sensing in forest fire detection and burned area mapping. Future research of using MODIS remote sensing technology in forest fire detection and mapping in both countries were also deeply described
Environmental-friendly food products’ packaging: women’s purchasing preferences
No full textPlastic pollution is a recent global issue. Its utilisation
has increased tremendously in all aspects of life. Marine wildlife is
a major threat group. As a result of these environmental
degradation caused by plastics, there are various effort to manage
it sustainably. This includes innovation in plastic-based product
packaging. There are increasing interests in the field of
ethical/responsible consumption as many campaigns are driving
the environmentally-friendly consumerism. This paper is focusing
on explaining women’s purchasing preference in the
environmental-friendly product packaging. Cross-sectional data
were collected through a web-based survey. The research
population consisted of women consumers who are working in
Klang Valley, Malaysia. A three-part questionnaire was used as
an instrument; demographic profiles, purchasing patterns and
purchasing preference. Only 3.5% of respondents preferred to buy
grocery items made from environmental-friendly packaging
materials. This result complicates the food packaging waste
pollution problems, as 70% of the purchasing of the grocery items
is made on a weekly basis which will intensify the
non-biodegradable plastic pollution problems
A method of mapping forest fuel types in peat swamp forest
No full textIn response to growing concerns over the burning of peat swamp forests, researchers have begun developing methods of mapping forest fire. Forest fire is one of the major causes of deforestation of tropical peat swamps in Malaysia. A way of identifying which peat swamp forest is vulnerable to forest fire is to develop a fuel type map to classify forest fire into different risk levels. In this study, remote sensing and geographical information system (GIS) techniques were integrated. Landsat Thematic Mapper (TM) image dated April 3rd, 1999, which corresponded to fire incident in this study area was used. The objective of this paper is to map fuel types in peat swamp forests. Results show that greenness and wetness components of Tasselled cap, used in classification, accurately captured greener and wetter area by combining supervised image and Tasselled cap image. The overall kappa statistics was 0.94 for combined supervised and Tasselled Cap classification. High values of kappa statistics for certain vegetation classes were due to the availability of representative pixels in the classes
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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