82 research outputs found
Continuous Cover Forestry and Remote Sensing: A Review of Knowledge Gaps, Challenges, and Potential Directions
Purpose of ReviewContinuous cover forestry (CCF) is a sustainable management approach for forestry in which forest stands are manipulated to create irregular stand structures with varied species composition. This approach differs greatly from the traditional approaches of plantation-based forestry, in which uniform monocultures are maintained, and thus, traditional methods of assessment, such as productivity (yield class) calculations, are less applicable. This creates a need to identify new methods to succeed the old and be of use in operational forestry and research. By applying remote sensing techniques to CCF, it may be possible to identify novel solutions to the challenges introduced through the adoption of CCF.Recent FindingsThere has been a limited amount of work published on the applications of remote sensing to CCF in the last decade. Research can primarily be characterised as explorations of different methods to quantify the target state of CCF and monitor indices of stand structural complexity during transformation to CCF, using terrestrial and aerial data collection techniques.SummaryWe identify a range of challenges associated with CCF and outline the outstanding gaps within the current body of research in need of further investigation, including a need for the development of new inventory methods using remote sensing techniques. We identify methods, such as individual tree models, that could be applied to CCF from other complex, heterogenous forest systems and propose the wider adoption of remote sensing including information for interested parties to get started
Current Trends in Forest Ecological Applications of Three-Dimensional Remote Sensing: Transition from Experimental to Operational Solutions?
The alarming increase in the magnitude and spatiotemporal patterns of changes in composition, structure and function of forest ecosystems during recent years calls for enhanced cross-border mitigation and adaption measures, which strongly entail intensified research to understand the underlying processes in the ecosystems as well as their dynamics. Remote sensing data and methods are nowadays the main complementary sources of synoptic, up-to-date and objective information to support field observations in forest ecology. In particular, analysis of three-dimensional (3D) remote sensing data is regarded as an appropriate complement, since they are hypothesized to resemble the 3D character of most forest attributes. Following their use in various small-scale forest structural analyses over the past two decades, these sources of data are now on their way to be integrated in novel applications in fields like citizen science, environmental impact assessment, forest fire analysis, and biodiversity assessment in remote areas. These and a number of other novel applications provide valuable material for the Forests special issue “3D Remote Sensing Applications in Forest Ecology: Composition, Structure and Function”, which shows the promising future of these technologies and improves our understanding of the potentials and challenges of 3D remote sensing in practical forest ecology worldwide
3D Remote Sensing Applications in Forest Ecology: Composition, Structure and Function
Dear Colleagues, The composition, structure and function of forest ecosystems are the key features characterizing their ecological properties, and can thus be crucially shaped and changed by various biotic and abiotic factors on multiple spatial scales. The magnitude and extent of these changes in recent decades calls for enhanced mitigation and adaption measures. Remote sensing data and methods are the main complementary sources of up-to-date synoptic and objective information of forest ecology. Due to the inherent 3D nature of forest ecosystems, the analysis of 3D sources of remote sensing data is considered to be most appropriate for recreating the forest’s compositional, structural and functional dynamics. In this Special Issue of Forests, we published a set of state-of-the-art scientific works including experimental studies, methodological developments and model validations, all dealing with the general topic of 3D remote sensing-assisted applications in forest ecology. We showed applications in forest ecology from a broad collection of method and sensor combinations, including fusion schemes. All in all, the studies and their focuses are as broad as a forest’s ecology or the field of remote sensing and, thus, reflect the very diverse usages and directions toward which future research and practice will be directed
Continuous Cover Forestry and Remote Sensing : A Review of Knowledge Gaps, Challenges, and Potential Directions
Canonical Correlation Analysis for Interpreting Airborne Laser Scanning Metrics along the Lorenz Curve of Tree Size Inequality
Canonical Correlation Analysis for Interpreting Airborne Laser Scanning Metrics along the Lorenz Curve of Tree Size Inequalit
Diversity and Equitability Ordering Profiles Applied to the Study of Forest Structure
Diversity and Equitability Ordering Profiles Applied to the Study of Forest Structur
Optimizing the airborne laser scanning estimation of basal area larger than mean (BALM): An indicator of cohort balance in forests
Airborne laser scanning (ALS) assisted basal area larger than mean (BALM) estimation measures the cohort balance in forests and provides adequate opportunities to describe forest structure. However, a problem still exists that how the plot size, sample size (number of trees), and ALS point density affect the BALM estimation. We tackled this question by using both field and ALS data from a typical managed boreal forest area in Finland. Various concentric circular plots (1-15 m radii) were simulated within the actual field plots (squared) and the optimal plot size and sample size were selected by observing changes in the absolute correlation between BALM estimates and various ALS metrics. Instability in the correlation was found at the smaller concentric circular plots (1-5 m radii) and sample sizes (less than 6 trees) but as the plot size and sample size increased, the correlation followed a convex curve. The maximum correlation was found between a concentric circular plot size 11-14 m radii (380-615 m2 area) and sample size 50-80 trees which could be the optimal plot size and sample size for a reliable BALM estimation. With regards to the ALS point density, no major effects were observed on the relationship between BALM estimates and various ALS metrics unless the point density is less than at least 5 points m 2. The point density of the current nationwide ALS survey is matching the minimum point density requirement obtained in this study and thus it is suitable for a reliable forest structural assessment
Cartography of uncertainty of predicted forest variables estimated from ALS data
cartografía de incertidumbre
Efecto del choque de temperatura y tiempo sobre la fertilización y sobrevivencia de larvas de bocachico (Prochilodus magdalenae) sometidos a tratamientos de triploidización
La inducción a la poliploidía en organismos acuáticos, permite mejorar su desempeño en cultivo, debido a que no alcanzan la madurez sexual, por lo que existe un control sobre la población; además en el ámbito ambiental, específicamente aplicado a programas de repoblamiento con individuos estériles, se atenúan o eliminan riesgos ligados a la interacción reproductiva con poblaciones naturales residentes en el medio, lo que posibilita conservar la diversidad genética y evitar endogamia. El objetivo de este trabajo fue evaluar el efecto de dos rangos de temperatura (0-4 y 4-8°C) y tres tiempos de choque térmico (5, 10 y 15 min) sobre los porcentajes de fertilización y sobrevivencia larvaria en bocachico (Prochilodus magdalenae). Para esto se realizó reproducción inducida mediante tratamiento hormonal con Extracto de Hipófisis de Carpa (EHC) a machos y hembras que presentaran signos de madurez avanzada. Una vez obtenido el desove, se utilizaron muestras de 1g aproximadamente para realizar los diferentes tratamientos (5 min post fertilización). Una vez realizado el choque térmico, las muestras fueron incubadas en contenedores de flujo ascendente de 2L de capacidad, a las 6 Horas Post Fertilización (HPF) se cuantificó el porcentaje de fertilización y a las 10 HPE el porcentaje de sobrevivencia larvaria. Se observó para el control los mayores valores con relación a los porcentajes de fertilización y sobrevivencia. Solo en el tratamiento 6 se observó triploidía en los organismos evaluados por medio de la cuantificación de los cromosomas. La obtención de un método práctico y efectivo para la inducción a la triploidía es necesario para poder considerar la triploidía como una tecnología de aplicación comercial, por lo que se deben considerar la realización de más investigaciones relacionadas con el manejo de ovocitos y efecto de los choques térmicos en las larvas de especies de interés para cultivo y programas de repoblamiento (malformaciones)
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