Predicting lodgepole pine site index from climatic parameters in Alberta

2006 ◽  
Vol 82 (4) ◽  
pp. 562-571 ◽  
Author(s):  
Robert A Monserud ◽  
Shongming Huang ◽  
Yuqing Yang

We sought to evaluate the impact of climatic variables on site productivity of lodgepole pine (Pinus contorta var. latifolia Engelm.) for the province of Alberta. Climatic data were obtained from the Alberta Climate Model, which is based on 30- year normals from the provincial weather station network. Mapping methods were based on ANUSPLIN, Hutchinson's thin-plate smoothing spline in four dimensions (latitude, longitude, elevation, climatic variable). Site indices based on stem analysis (observed dominant height at an index age of 50 years at breast height) were used as a measure of forest site productivity. A total of 1145 site index plots were available for lodgepole pine, the major forest species in Alberta. Regression analyses were used to predict site index as a function of climatic variables for each plot. The strongest linear predictors of site index were growing degree days > 5° (GDD5), the Julian date when GDD5 reaches 100 (D100), and July mean temperature (MTWM).A nonlinear model with D100 as the predictor variable was chosen as the final model. Both the observed and the predicted site indices from the 1145 locations were interpolated using ANUSPLIN and mapped using ArcView. We concluded that climate is an important component of site productivity, accounting for about one quarter of the variation in lodgepole pine site index across the province. Key words: site index, climate variable, Alberta Climate Model, ANUSPLIN, site productivity map, lodgepole pine

2020 ◽  
Vol 66 (3) ◽  
pp. 275-283 ◽  
Author(s):  
Halli Hemingway ◽  
Mark Kimsey

Abstract Accurate measures of forest site productivity are essential for forest-management planning. The most common measure of site productivity is breast height–age site index (BHASI)—the expected height at a reference age. Error from including early growth in productivity estimates and limited applicability of any one BHASI model warrant development of alternative methods. Exploring alternatives may only be necessary if regional BHASI models are not accurately predicting growth rates. We compared modeled height growth rates for Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca) to felled-tree measurements to evaluate relative performance of a regional BHASI model. An orthogonal sampling design ensured samples were collected across a range of site factors known to influence Douglas-fir growth rates. Growth rates for each 10 m section were calculated and compared to BHASI modeled growth rates. The regional BHASI model underpredicted growth rates from breast height to 30 m. Observed growth rates from 10 to 30 m accounted for the majority of underprediction relative to BHASI modeled growth rates. An alternative multipoint method of defining site productivity is described. More research comparing BHASI and alternative methods is needed, given the growth rate error associated with one-point site productivity assessment.


2004 ◽  
Vol 19 (3) ◽  
pp. 154-159 ◽  
Author(s):  
G. Geoff Wang ◽  
Shongming Huang ◽  
David J. Morgan

Abstract Based on the provincial stem analysis and permanent sample plot (PSP) data of 1,580 felled dominant and codominant trees, height growth patterns of lodgepole pine were compared among the three major natural subregions [Sub-Alpine (SAL), Upper Foothills (UFH), and Lower Foothills (LFH)] in Alberta. The comparison used the ratio of heights at 70 and 30 years of breast height age (Z ratio) as a quantitative measure of height growth pattern (i.e., the response variable), site index (height at breast height age of 50 years) as the covariate, and natural subregion as the factor. Results indicated that: (1) the height growth pattern in the SAL natural subregion was significantly different from other natural subregions; and (2) no significant differences in height growth pattern were found between other natural subregions. Two polymorphic height and site index curves were developed: one for the SAL natural subregion and the other for the UFH and LFH natural subregions. Comparisons between the two curves and the previously developed provincial curve indicated that, for the same site index, trees in the SAL subregion grow consistently slower after 50 years. When the provincial height and site index curve was applied to the SAL natural subregion, large differences (≤14%) in gross volume estimation were found. However, volume estimation differences were very small (<2%) when the provincial curve was applied to the other two natural subregions. It is recommended that the natural subregion-based curves should be used for predicting lodgepole pine site index or height at any age in the SAL natural subregion. West. J. Appl. For. 19(3):154–159.


2018 ◽  
Vol 41 (3) ◽  
Author(s):  
Susana Mestre ◽  
Cristina Alegria ◽  
Maria Teresa Durães Albuquerque ◽  
Pierre Goovaerts

ABSTRACT Productivity is very dependent on the environmental and biotic factors present at the site where the forest species of interest is present. Forest site productivity is usually assessed using empirical models applied to inventory data providing discrete predictions. While the use of GIS-based models enables building a site productivity distribution map. Therefore, the aim of this study was to derive a productivity index using multivariate statistics and coupled GIS-geostatistics to obtain a forest productivity map. To that end, a study area vastly covered by naturally regenerated forests of maritime pine in central Portugal was used. First, a productivity index (PI) was built based on Factorial Correspondence Analysis (FCA) by incorporating a classical site index for the species and region (Sh25 - height index model) and GIS-derived environmental variables (slope and aspect). After, the PI map was obtained by multi-Gaussian kriging and used as a GIS layer to evaluate maritime pine areas by productivity class (e.g., low, intermediate and high). In the end, the area control method was applied to assess the size and the number of compartments to establish by productivity class. The management compartments of equal productivity were digitized as GIS layer and organized in a temporal progression of stands’ age regularly available for cutting each year during a 50-year schedule. The methodological approach developed in this study proved that can be used to build forest productivity maps which are crucial tools to support forest production regulation.


2021 ◽  
Vol 19 (1) ◽  
pp. 112-130
Author(s):  
A. A. SADIQ

Flood is a seasonal phenomenon which is natural in it hazardous implication and occurs when there is relative high flow over the banks of the streams as a combine consequence of  high recorded data of hydro-climatic related variables in a given geographical area.  Yola North LGA, of Adamawa state had experienced an unprecedented flood in the year 2012 over the past decade which might have been influenced by some hydro-climatic variables and caused devastating effects on lives, properties, farmland and buildings respectively. This study focused on the impact assessment of substantive hydro-climatic variables on 2012 flood event in Yola -North and its environs. The hydro-climatic variables data were obtained from Meteorological station at UBRBDA, Yola for a decade. The amount of rainfall experienced was found to be highest (1085.2mm) in the year 2012 than any other year under consideration (2008-2017) except that of 2016, number of rainy days was highest (81 days) in the year 2012. Similarly, in the month of August in the year 2012 evaporation rate was lowest with about 69 mm than any other month of August in the decade, the annual value of water discharge was highest in the year 2012 over the decade with about 6,340(m3/s), the gauge height was found to be highest with about 7.33 m in the year 2012 and the water level was highest in the month of June, July and September  with the corresponding values of 3.37 m, 3.49 m and 6.58 m compared to similar months in the years of the decade respectively. These increased changes in some hydro-climatic data analyzed might be the fundamental natural factor that causes the unique flooding than any other factor in the year 2012 in the study area and over time posed negative impact on agricultural lands.  Therefore, the study recommends the urgent need to carry out a comprehensive seasonal hydro-climatic data record simulation analysis and variations with a view of taking them as a recipe and strategies of forecasting and predicting the reoccurrence of such phenomenon. The additional meteorological station should be provided by the government agencies in all agricultural zones of the state for adequate and wide range of hydro-climatic data recording for appropriate prediction of weather indices in future.      


2012 ◽  
pp. 17-34
Author(s):  
Dragana Cavlovic ◽  
Dragica Obratov-Petkovic ◽  
Mirjana Ocokoljic ◽  
Vladimir Djurdjevic

Wetlands are among the most vulnerable habitats on the planet. Very complex forest ecosystems are also parts of wetlands. Research and analysis of forest vegetation elements, leads to a conclusion about ecological conditions of wetlands. The aim of the paper is detail forest vegetation study, and analyzing the impact of climate changes on wetland forest vegetations of the strict protection area at the SNR Zasavica Ramsar site. Field research was carried out by using Braun-Blanquet?s Zurich-Montpelier school method. Phytogeographical elements and life forms of plants were determined subsequently, in order to get indicator values of wetland plants. Coupled Regional Climate Model (CRCM), EBU-POM was used for the climate simulations. Exact climatic variables for the site were determined by downscaling method. Climatic variables reference values were taken for the period of 1961-1990, and climate change simulations for the period 2071-2100 (A1B and A2). Indicator values of forest plants taken into consideration were humidity and temperature; therefore, ecological optimums were determined in scales of humidity and temperature. Regional Climate Model shows that there will be a long and intensive dry period in the future, with high temperatures from April till October. Continental winter will be more humid, with higher precipitation, especially in February. Based on the analysis of results it was concluded that wetlands are transitional habitats, also very variable and therefore vulnerable to changes. The changes may lead to the extinction of some plant species.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Gonghuan Fang ◽  
Jing Yang ◽  
Yaning Chen ◽  
Shuhua Zhang ◽  
Haijun Deng ◽  
...  

To study the impact of future climatic changes on hydrology in the Kaidu River Basin in the Tianshan Mountains, two sets of future climatic data were used to force a well-calibrated hydrologic model: one is bias-corrected regional climate model (RCM) outputs for RCP4.5 and RCP8.5 future emission scenarios, and the other is simple climate change (SCC) with absolute temperature change of −1~6°C and relative precipitation change of −20%~60%. Results show the following: (1) temperature is likely to increase by 2.2°C and 4.6°C by the end of the 21st century under RCP4.5 and RCP8.5, respectively, while precipitation will increase by 2%~24%, with a significant rise in the dry season and small change in the wet season; (2) flow will change by −1%~20%, while evapotranspiration will increase by 2%~24%; (3) flow increases almost linearly with precipitation, while its response to temperature depends on the magnitude of temperature change and flow decrease is significant when temperature increase is greater than 2°C; (4) similar results were obtained for simulations with RCM outputs and with SCC for mild climate change conditions, while results were significantly different for intense climate change conditions.


2008 ◽  
Vol 38 (2) ◽  
pp. 343-352 ◽  
Author(s):  
Robert A. Monserud ◽  
Yuqing Yang ◽  
Shongming Huang ◽  
Nadja Tchebakova

We estimated the impact of global climate change on lodgepole pine ( Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) site productivity in Alberta based on the Alberta Climate Model and the A2 SRES climate change scenario projections from three global circulation models (CGCM2, HADCM3, and ECHAM4). Considerable warming is apparent in all three models. On average, the increases in mean GDD5 (growing degree-days >5 °C) are 18%, 38%, and 65% by the 2020s, 2050s, and 2080s, respectively. Change in precipitation is essentially nil. This results in proportional increases in dryness index. We used the dryness index to predict the potential future range and GDD5 to predict its potential productivity. Generally, lodgepole pine site index is predicted to increase steadily by 3 m for each 30-year period. Offsetting this increase is a large reduction in suitable area as drying increases. At first, the warming increases the potential range up to 67% by the 2020s but then shrinks from 34% to 58% of its current area by 2080. Such major changes will need to be considered when setting long-term forest management plans. The increased risk of both wildfire and insect outbreaks further compounds this planning problem, especially because these disturbance events can interact and further increase risk.


2011 ◽  
Vol 87 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Bharat Pokharel ◽  
Jeffery P Dech

Forest site classification is a prerequisite to successful integrated forest resources planning and management. Traditionally,site classification has emphasized a phytocentric approach, with tools such as the site index having a rich and longhistory in forest site evaluation. The concept of site index was primarily devised to assess site productivity of an even-aged,single-species stand. Site index has been the primary method of forest site evaluation in support of management for traditionalforest products. However, this method of site classification has been criticized as the needs, perspectives andsocial values of the public regarding forest management have changed the emphasis from timber production to multiplevalueforestry practices. There are alternative approaches to forest site classification that have the potential to meet thegrowing demands placed on forest information for inventory and modeling purposes. Ecological Land Classification(ELC), is a phytogeocentric approach that stratifies the landscape into ecologically meaningful units (ecosites) based onsubstrate characteristics, moisture regime and canopy composition. This approach offers a more holistic view of site productivityevaluation; however, until recently it has been difficult to acquire data to support widespread mapping ofecosites. Remote sensing technology along with predictive modeling and interpretive mapping techniques make the applicationof an ecosite-based approach at the forest landscape level possible. As forest management moves towards the considerationof a broader set of resources (e.g., woody biomass), there is an opportunity to develop new tools for linking forestproductivity to the sustainable production of forest bioproducts with forest ecosites as a solid foundation forsegmenting the landscape. Key words: forest site classification, site index, site productivity, Ecological Land Classification (ELC), ecosites, forest biomass,bioproducts


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Sylvia Ankamah ◽  
Kaku S. Nokoe ◽  
Wahab A. Iddrisu

Malaria is considered endemic in over hundred countries across the globe. Many cases of malaria and deaths due to malaria occur in Sub-Saharan Africa. The disease is of great public health concern since it affects people of all age groups more especially pregnant women and children because of their vulnerability. This study sought to use vector autoregression (VAR) models to model the impact of climatic variability on malaria. Monthly climatic data (rainfall, maximum temperature, and relative humidity) from 2010 to 2015 were obtained from the Ghana Meteorological Agency while data on malaria for the same period were obtained from the Ghana Health Service. Results of the Granger and instantaneous causality tests led to a conclusion that malaria is influenced by all three climatic variables. The impulse response analyses indicated that the highest positive effect of maximum temperature, relative humidity, and rainfall on malaria is observed in the months of September, March, and October, respectively. The decomposition of forecast variance indicates varying degree of malaria dependence on the climatic variables, with as high as 12.65% of the variability in the trend of malaria which has been explained by past innovations in maximum temperature alone. This is quite significant and therefore, policy-makers should not ignore temperature when formulating policies to address malaria.


2007 ◽  
Vol 20 (14) ◽  
pp. 3621-3634 ◽  
Author(s):  
Kirsten L. Findell ◽  
Elena Shevliakova ◽  
P. C. D. Milly ◽  
Ronald J. Stouffer

Abstract Equilibrium experiments with the Geophysical Fluid Dynamics Laboratory’s climate model are used to investigate the impact of anthropogenic land cover change on climate. Regions of altered land cover include large portions of Europe, India, eastern China, and the eastern United States. Smaller areas of change are present in various tropical regions. This study focuses on the impacts of biophysical changes associated with the land cover change (albedo, root and stomatal properties, roughness length), which is almost exclusively a conversion from forest to grassland in the model; the effects of irrigation or other water management practices and the effects of atmospheric carbon dioxide changes associated with land cover conversion are not included in these experiments. The model suggests that observed land cover changes have little or no impact on globally averaged climatic variables (e.g., 2-m air temperature is 0.008 K warmer in a simulation with 1990 land cover compared to a simulation with potential natural vegetation cover). Differences in the annual mean climatic fields analyzed did not exhibit global field significance. Within some of the regions of land cover change, however, there are relatively large changes of many surface climatic variables. These changes are highly significant locally in the annual mean and in most months of the year in eastern Europe and northern India. They can be explained mainly as direct and indirect consequences of model-prescribed increases in surface albedo, decreases in rooting depth, and changes of stomatal control that accompany deforestation.


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