Uncertainty in Extrapolations of Predictive Land-Change Models

2005 ◽  
Vol 32 (2) ◽  
pp. 211-230 ◽  
Author(s):  
Robert Gilmore Pontius ◽  
Joseph Spencer

This paper gives a technique to extrapolate the anticipated accuracy of a prediction of land-use and land-cover change (LUCC) to any point in the future. The method calibrates a LUCC model with information from the past in order to simulate a map of the present, so that it can compute an objective measure of validation with empirical data. Then it uses that observed measurement of predictive accuracy to anticipate how accurately the model will predict a future landscape. The technique assumes that the accuracy of the model will decay to randomness as the model predicts farther into the future and estimates how fast the decay in accuracy will occur based on prior model performance. Results are presented graphically in terms of percentage of pixels classified correctly so that nonexperts can interpret the accuracy visually. The percentage correct is budgeted by three components: agreement due to chance, agreement due to the predicted quantity of each land category, and agreement due to the predicted location of each land category. The percentage error is budgeted by two components: disagreement due to the predicted location of each land category and disagreement due to the predicted quantity of each land category. Therefore, model users can see the sources of the accuracy and error of the model. The entire analysis is computable for multiple resolutions, so users can see how the results are sensitive to changes in scale. We illustrate the method with an application of the land-use change model Geomod to Central Massachusetts, where the predictive accuracy of the model decays to 90% over fourteen years and to near complete randomness over 200 years.

Author(s):  
Neseredin Bashawal Mangel ◽  
Fitsum Berhe

Based on the recorded watershed characteristics, the future conditions on the basin system can be predicted using a different method. In this study, dynamic land-use change and its impacts on the streamflow for the Dabus watershed were predicted using ANN-CA based method. The model performance for accurate prediction of the future land-use change on the Dabus River watershed has been checked by validation of the simulated value with the actual value, hence the overall kappa value (k) = 0.83 for the simulated 2016-LULC validated with actual 2016-LULC. Then, 2026-LULC was predicted based on the 2004 and 2009-LULC. The streamflow for the case of 2004 and 2009-LULC has been simulated using the SWAT model. The value of NSE = 0.87 and 0.90 was attained during validation of simulated streamflow for 2004 and 2009-LULC data cases, respectively. The agreement of simulated value of streamflow with the observed data is indicated as R2 = 0.91 and 0.96 for 2004-LULC and 2009-LULC. The effects of the dynamic land-use change on streamflow for the predicted land use(2026-LULC) catchment were evaluated by T-test analysis. Hence, T-stat =0.04 and -0.002 in the case of simulated streamflow used 2004-LULC and 2009-LULC, respectively compared with simulated value using 2026-LULC.


2019 ◽  
Vol 3 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Iara Lacher ◽  
Thomas Akre ◽  
William J. McShea ◽  
Marissa McBride ◽  
Jonathan R. Thompson ◽  
...  

This case study describes the application of a framework for developing stakeholder-driven scenarios of the future. The purpose of these scenarios is to inform land use planning toward the protection of ecosystems and derivable ecosystem services in Northwestern Virginia. We held two scenario development workshops with regional experts in conservation, agriculture, land use planning, policy, and economic development to create scenarios of land use in the northern Piedmont and northern Shenandoah Valley of Virginia. We structured the workshops around a framework that guided stakeholders through several steps eventually resulting in four unique scenarios describing the region in 50 years. Scenario narratives were defined by the intersection of highly influential and uncertain drivers of change relevant to land use planning and ecosystem services. Participants from the northern Shenandoah Valley region selected population growth and climate change adaptation as their scenario defining drivers, while participants from the northern Piedmont region selected planning strategy and climate change impact as their scenario defining drivers. Participants fleshed out scenarios into descriptive narratives that incorporated qualitative and quantitative measures of change. Details from the scenario narratives informed land use change models to further quantify tradeoffs between land use planning decisions and ecosystem services. Individuals interested in using scenario planning to guide research efforts, conservation, or land use planning, or even to broaden perspectives on how to view the future, will find value in this case study.


2019 ◽  
Vol 43 (1) ◽  
Author(s):  
Meseret Hadgu ◽  
Habtamu Taddele Menghistu ◽  
Atkilt Girma ◽  
Haftu Abrha ◽  
Haftom Hagos

Abstract Background Climate change is believed to be continuously affecting ticks by influencing their habitat suitability. However, we attempted to model the climate change-induced impacts on future genus Rhipicephalus distribution considering the major environmental factors that would influence the tick. Therefore, 50 tick occuance points were taken to model the potential distribution using maximum entropy (MaxEnt) software and 19 climatic variables, taking into account the ability for future climatic change under representative concentration pathways (RCPs) 4.5 and 8.5, were used. Results MaxEnt model performance was tested and found with the AUC value of 0.99 which indicates excellent goodness-of-fit and predictive accuracy. Current models predict increased temperatures, both in the mid and end terms together with possible changes of other climatic factors like precipitation which may lead to higher tick-borne disease risks associated with expansion of the range of the targeted tick distribution. Distribution maps were constructed for the current, 2050, and 2070 for the two greenhouse gas scenarios and the most dramatic scenario; RCP 8.5 produced the highest increase probable distribution range. Conclusions The future potential distribution of the genus Rhipicephalus show potential expansion to the new areas due to the future climatic suitability increase. These results indicate that the genus population of the targeted tick could emerge in areas in which they are currently lacking; increased incidence of tick-borne diseases poses further risk which can affect cattle production and productivity, thereby affecting the livelihood of smallholding farmers. Therefore, it is recommended to implement climate change adaptation practices to minimize the impacts.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Fatih Sari

AbstractIn this study, landuse changes in the Muğla province were determined and future Land Use Cover Change (LUCC) maps were predicted. Because Muğla accounts for 90% of pine honey production in the world, the study area has vital importance for the Turkish (also for other countries) beekeeping sector and this importance reveals the necessity of both monitoring and predicting the LUCC of Muğla in future. This study demonstrates a combined CA-Markov land use change model and beekeeping suitability analysis via Multi-Criteria Decision Analysis (MCDA) to predict the future of beekeeping suitability in Muğla in the Geographical Information Systems (GIS) platform. 2006 and 2012 LUCC maps were used to predict the 2018 LUCC, and transition probabilities between land cover classes were analyzed. A recent 2018 LUCC map was used to demonstrate accuracy analysis of the predicted 2018 LUCC map. Considering the 0.96 Kappa accuracy, a good fit was determined and the CA-Markov model was used to predict the 2025, 2030, 2040 and 2050 LUCC maps. Moreover, using the Analytical Hierarchy Process (AHP), beekeeping suitability assessment was generated. The results indicate that there will be a considerable increase in the urban areas and decrease in grasslands in the future. Related to this, the suitable areas will be decreased by 50 km2 and non-suitable areas will be increased by 76 km2 from 2018 to 2050. The study simulated the beekeeping suitability to guide beekeepers and local authorities towards a better understanding of the reasons for decreasing suitability and developing urgent land use management systems.


Author(s):  
Luoman Pu ◽  
Jiuchun Yang ◽  
Lingxue Yu ◽  
Changsheng Xiong ◽  
Fengqin Yan ◽  
...  

Crop potential yields in cropland are the essential reflection of the utilization of cropland resources. The changes of the quantity, quality, and spatial distribution of cropland will directly affect the crop potential yields, so it is very crucial to simulate future cropland distribution and predict crop potential yields to ensure the future food security. In the present study, the Cellular Automata (CA)-Markov model was employed to simulate land-use changes in Northeast China during 2015–2050. Then, the Global Agro-ecological Zones (GAEZ) model was used to predict maize potential yields in Northeast China in 2050, and the spatio-temporal changes of maize potential yields during 2015–2050 were explored. The results were the following. (1) The woodland and grassland decreased by 5.13 million ha and 1.74 million ha respectively in Northeast China from 2015 to 2050, which were mainly converted into unused land. Most of the dryland was converted to paddy field and built-up land. (2) In 2050, the total maize potential production and average potential yield in Northeast China were 218.09 million tonnes and 6880.59 kg/ha. Thirteen prefecture-level cities had maize potential production of more than 7 million tonnes, and 11 cities had maize potential yields of more than 8000 kg/ha. (3) During 2015–2050, the total maize potential production and average yield decreased by around 23 million tonnes and 700 kg/ha in Northeast China, respectively. (4) The maize potential production increased in 15 cities located in the plain areas over the 35 years. The potential yields increased in only nine cities, which were mainly located in the Sanjiang Plain and the southeastern regions. The results highlight the importance of coping with the future land-use changes actively, maintaining the balance of farmland occupation and compensation, improving the cropland quality, and ensuring food security in Northeast China.


Author(s):  
Jane J. Aggrey ◽  
Mirjam A. F. Ros-Tonen ◽  
Kwabena O. Asubonteng

AbstractArtisanal and small-scale mining (ASM) in sub-Saharan Africa creates considerable dynamics in rural landscapes. Many studies addressed the adverse effects of mining, but few studies use participatory spatial tools to assess the effects on land use. Hence, this paper takes an actor perspective to analyze how communities in a mixed farming-mining area in Ghana’s Eastern Region perceive the spatial dynamics of ASM and its effects on land for farming and food production from past (1986) to present (2018) and toward the future (2035). Participatory maps show how participants visualize the transformation of food-crop areas into small- and large-scale mining, tree crops, and settlement in all the communities between 1986 and 2018 and foresee these trends to continue in the future (2035). Participants also observe how a mosaic landscape shifts toward a segregated landscape, with simultaneous fragmentation of their farming land due to ASM. Further segregation is expected in the future, with attribution to the expansion of settlements being an unexpected outcome. Although participants expect adverse effects on the future availability of food-crop land, no firm conclusions can be drawn about the anticipated effect on food availability. The paper argues that, if responsibly applied and used to reveal community perspectives and concerns about landscape dynamics, participatory mapping can help raise awareness of the need for collective action and contribute to more inclusive landscape governance. These findings contribute to debates on the operationalization of integrated and inclusive landscape approaches and governance, particularly in areas with pervasive impacts of ASM.


1978 ◽  
Vol 5 (3) ◽  
pp. 334-339
Author(s):  
Brian E. Sullivan

The transit system serving Greater Vancouver has high ridership and a high rate of growth. Using as a base the well-designed, well-patronized trolleybus grid in the City of Vancouver, an inter-connected suburban bus network has been created, with radial, cross-radial, and local routes meeting on a timed connection basis at suburban shopping centres and other foci. Planners' thoughts for the future include greater emphasis on the micro and macro aspects of land use and relations to transit; the use of capital intensive modes for heavy trunk routes; and the use of various forms of para-transit for low-density and certain feeder applications.


2002 ◽  
Vol 46 (1) ◽  
Author(s):  
Dietrich Schmidt-Vogt

AbstractManagement of secondary tropical forests: a new perspective for sustainable use of forests in Asia. The decline of primary forests in the tropics is leading to a reassessment of the role secondary forests might play within the context of tropical forest management. Recent research has shown that secondary forests in the tropics can be both rich in species and complex in terms of stand structure. There is, moreover, a growing recognition of the importance of secondary forests for traditional subsistence economies in the tropics and of their economic potential for land use systems in the future. Management of secondary forests in Asia as an alternative to the extraction of timber from primary forests but also as one among other options to intensify traditional land use systems has a potential for the future especially because of the existence of vast tracts of valuable secondary forest cover, and because of the store of traditional knowledge that can still be found in tropical Asia.


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