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Modelling scenarios of land use change in northern China in the next 50 years

HE Chunyang,LI Jinggang,SHI Peijun,CHEN Jin,PAN Yaozhong,LI Xiaobing,

地理学报 , 2005,
Abstract: Modelling scenarios of land use change and their impacts in typical regions are helpful to investigate the mechanism between land use and ecological systems and process the land use allocation under the ecological security. A system dynamics (SD) model with the aim to modelling scenarios of land use change and assessing ecological impact in northern China in the next 50 years is developed here. The accuracy assessment with the historic data from 1990 to 2001 indicated the SD model is robust. After the different "what-if" scenarios controlled by GDP, population, market, and technology advancement were built, the different scenarios of land use change in northern China from 2000 to 2050 were simulated with their ecological impact assessed. The result suggested that such factors as GDP, population, market and technology have a strong relationship with land use structural change in northern China. It also indicated that such measures as strict controlling of population increase, importing some food to keep the supply-demand balance in the region, and improving agricultural technology will be the guarantee of regional sustainable development with fast economic growth and the obvious land use structural improvement at the same time.
Land Use Scenarios and Optimization in a Watershed  [PDF]
D. Nikkami,M. Shabani,H. Ahmadi
Journal of Applied Sciences , 2009,
Abstract: The main objective of this research is to study the optimized combination of land allocation to different land uses like rangeland, orchard, irrigated farming and dry farming for minimized soil erosion and maximized people`s net income in Kharestan watershed located in the Northwest of Eghlid, Fars province, Iran. A multi-objective Linear Programming (LP) model was applied in three different land use scenarios including existing land uses plus land management (Scenario 1), existing land uses with some degree of land management (Scenario 2), and proper land uses plus land management (Scenario 3). The amount of soil loss and net benefit in each land use were computed and used as inputs to formulate the objective functions and governing constraints in optimization problem. The problem was solved using the simplex method with the help of LINGO software package and the optimal solution was ultimately determined. The results showed that in the optimized condition, while rangelands experience no change, the area of orchards should be increased from 561 to 2115 ha (377%), irrigated farms should be reduced from 871 to 237 ha (73%) and dry farming lands should be decreased from 1050 to 129 ha (88%). Also, by existing land management, land use optimization decreases soil erosion by 3.7% and increases net income by 163%. In existing land use some land management implementation, decreases soil erosion by 37% and increases net income by 206%, while in proper land uses and management, soil erosion decreases by 53% and net income increases by 208%. Sensitivity analysis showed that the area of orchards and rangelands are the most sensitive parameters and their changes have the highest effect on the amount of net income and soil erosion.
Apparent Temperature and Cause-Specific Emergency Hospital Admissions in Greater Copenhagen, Denmark  [PDF]
Janine Wichmann, Zorana Andersen, Matthias Ketzel, Thomas Ellermann, Steffen Loft
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0022904
Abstract: One of the key climate change factors, temperature, has potentially grave implications for human health. We report the first attempt to investigate the association between the daily 3-hour maximum apparent temperature (Tappmax) and respiratory (RD), cardiovascular (CVD), and cerebrovascular (CBD) emergency hospital admissions in Copenhagen, controlling for air pollution. The study period covered 1 January 2002?31 December 2006, stratified in warm and cold periods. A case-crossover design was applied. Susceptibility (effect modification) by age, sex, and socio-economic status was investigated. For an IQR (8°C) increase in the 5-day cumulative average of Tappmax, a 7% (95% CI: 1%, 13%) increase in the RD admission rate was observed in the warm period whereas an inverse association was found with CVD (?8%, 95% CI: ?13%, ?4%), and none with CBD. There was no association between the 5-day cumulative average of Tappmax during the cold period and any of the cause-specific admissions, except in some susceptible groups: a negative association for RD in the oldest age group and a positive association for CVD in men and the second highest SES group. In conclusion, an increase in Tappmax is associated with a slight increase in RD and decrease in CVD admissions during the warmer months.
Land Change in the Greater Antilles between 2001 and 2010  [PDF]
Nora L. álvarez-Berríos,Daniel J. Redo,T. Mitchell Aide,Matthew L. Clark,Ricardo Grau
Land , 2013, DOI: 10.3390/land2020081
Abstract: Land change in the Greater Antilles differs markedly among countries because of varying socioeconomic histories and global influences. We assessed land change between 2001 and 2010 in municipalities (second administrative units) of Cuba, Dominican Republic, Haiti, Jamaica, and Puerto Rico. Our analysis used annual land-use/land-cover maps derived from MODIS satellite imagery to model linear change in woody vegetation, mixed-woody/plantations and agriculture/herbaceous vegetation. Using this approach, we focused on municipalities with significant change ( p ≤ 0.05). Between 2001 and 2010, the Greater Antilles gained 801 km 2 of woody vegetation. This increase was mainly due to the return of woody vegetation in Cuba, and smaller increases in Puerto Rico and the Dominican Republic. Despite relatively similar environments, the factors associated with these changes varied greatly between countries. In Puerto Rico, Dominican Republic, and Jamaica, agriculture declined while mixed-woody vegetation increased, mostly in montane regions. In contrast, Cuba experienced an extensive decline in sugarcane plantations, which resulted in the spread of an invasive woody shrub species and the increase in woody vegetation in areas of high agricultural value. In Haiti, the growing population, fuelwood consumption, and increase in agriculture contributed to woody vegetation loss; however, woody vegetation loss was accompanied with a significant increase in the mixed woody and plantations class. Most regional analyses often treated the Greater Antilles as a homogeneous unit; our results suggest that historical and socio-economic differences among countries are crucial for understanding the variation in present day land change dynamics.
Hydrological responses of a watershed to historical land use evolution and future land use scenarios under climate change conditions
R. Quilbé, A. N. Rousseau, J.-S. Moquet, S. Savary, S. Ricard,M. S. Garbouj
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2008,
Abstract: Watershed runoff is closely related to land use but this influence is difficult to quantify. This study focused on the Chaudière River watershed (Québec, Canada) and had two objectives: (i) to quantify the influence of historical agricultural land use evolution on watershed runoff; and (ii) to assess the effect of future land use evolution scenarios under climate change conditions (CC). To achieve this, we used the integrated modeling system GIBSI. Past land use evolution was constructed using satellite images that were integrated into GIBSI. The general trend was an increase of agricultural land in the 80's, a slight decrease in the beginning of the 90's and a steady state over the last ten years. Simulations showed strong correlations between land use evolution and water discharge at the watershed outlet. For the prospective approach, we first assessed the effect of CC and then defined two opposite land use evolution scenarios for the horizon 2025 based on two different trends: agriculture intensification and sustainable development. Simulations led to a wide range of results depending on the climatologic models and gas emission scenarios considered, varying from a decrease to an increase of annual and monthly water discharge. In this context, the two land use scenarios induced opposite effects on water discharge and low flow sequences, especially during the growing season. However, due to the large uncertainty linked to CC simulations, it is difficult to conclude that one land use scenario provides a better adaptation to CC than another. Nevertheless, this study shows that land use is a key factor that has to be taken into account when predicting potential future hydrological responses of a watershed.
What happened to forests in Copenhagen?
Grassi G,Federici S,Pilli R
iForest : Biogeosciences and Forestry , 2010, DOI: 10.3832/ifor0529-003
Abstract: After the chaotic final days of the Copenhagen climate conference, many saw only fog, i.e., an unclear outcome and much uncertainty on future steps to take. Were the forests lost in this fog or some tree is still visible, possibly suggesting a path to take? This commentary will briefly analyse the outcome of the Copenhagen conference with respect to the main forestry issues under debate: LULUCF (Land Use Land Use Change and Forestry, i.e., mainly forest CO2 removals in industrialized countries) and REDD (Reducing Emissions from Deforestation and forest Degradation in developing countries).
Hydrological responses of a watershed to historical land use evolution and future land use scenarios under climate change conditions
R. Quilbé,A. N. Rousseau,J.-S. Moquet,S. Savary
Hydrology and Earth System Sciences Discussions , 2007,
Abstract: Watershed runoff is closely related to land use, but this influence is difficult to quantify. This study focused on the Chaudière River watershed (Québec, Canada) and had two objectives: (i) to quantify the influence of historical agricultural land use evolution on watershed runoff; and (ii) to assess the effect of future land use evolution scenarios under climate change conditions (CC). To achieve this, we used the integrated modeling system GIBSI. Past land use evolution was constructed using satellite images that were integrated into GIBSI. The general trend was an increase of agricultural land in the 1980s, a slight decrease in the beginning of the 1990s and a steady state over the last ten years. Simulations based on thirty years of daily meteorological series showed strong correlations between land use evolution and water discharge at the watershed outlet, especially for summer and fall seasons. For the prospective approach, we first assessed the effect of CC and then defined two opposite land use evolution scenarios for the horizon 2025 based on two different trends: agriculture intensification or sustainable development. Simulation results showed that CC would induce an increase of water discharge during winter and a decrease the rest of the year, while land use scenarios would have a more drastic effect, agriculture intensification counterbalancing the effect of CC during summer and fall. Due to the large uncertainty linked to CC simulations, it is difficult to conclude that one land use scenario provides a better adaptation to CC than another, but this study shows that land use is a key factor that has to be taken into account when predicting potential future hydrological responses of a watershed.
A stochastic Forest Fire Model for future land cover scenarios assessment  [PDF]
M. D'Andrea,P. Fiorucci,T. P. Holmes
Natural Hazards and Earth System Sciences (NHESS) & Discussions (NHESSD) , 2010, DOI: 10.5194/nhess-10-2161-2010
Abstract: Land cover is affected by many factors including economic development, climate and natural disturbances such as wildfires. The ability to evaluate how fire regimes may alter future vegetation, and how future vegetation may alter fire regimes, would assist forest managers in planning management actions to be carried out in the face of anticipated socio-economic and climatic change. In this paper, we present a method for calibrating a cellular automata wildfire regime simulation model with actual data on land cover and wildfire size-frequency. The method is based on the observation that many forest fire regimes, in different forest types and regions, exhibit power law frequency-area distributions. The standard Drossel-Schwabl cellular automata Forest Fire Model (DS-FFM) produces simulations which reproduce this observed pattern. However, the standard model is simplistic in that it considers land cover to be binary – each cell either contains a tree or it is empty – and the model overestimates the frequency of large fires relative to actual landscapes. Our new model, the Modified Forest Fire Model (MFFM), addresses this limitation by incorporating information on actual land use and differentiating among various types of flammable vegetation. The MFFM simulation model was tested on forest types with Mediterranean and sub-tropical fire regimes. The results showed that the MFFM was able to reproduce structural fire regime parameters for these two regions. Further, the model was used to forecast future land cover. Future research will extend this model to refine the forecasts of future land cover and fire regime scenarios under climate, land use and socio-economic change.
Research for Scenarios Simulation of Urban Land Use Change in Beijing by System Dynamic Model under Water Restriction from 2004 to 2020
水资源约束下北京地区2004-2020年土地利用变化情景模拟研究

WANG Shuang,HE Chun-yang,PAN Yao-zhong,YANG Ming-chuan,
王双
,何春阳,潘耀忠,杨明川

自然资源学报 , 2006,
Abstract: Modelling scenarios of land use change under natural resources restriction in typical regions are helpful and significant in investigating the mechanism between land use and natural resources and processing the land use allocation under the resource security.A system dynamic(System Dynamics,SD)model under water restriction aiming at simulating urban land use change is developed in this paper.The model studies different "what-if" scenarios of urban land use change which are controlled by the restricted water resource,along with other elements,such as population,economy and technology advancement.In addition,the model is applied in Beijing.The accuracy assessment with the historical data in Beijing from 1980 to 2003 indicates that this SD model is available to understand the restriction of water resource to land use change and social development.The scenarios simulation of urban land use in Beijing from 2004 to 2020 suggests that natural resources exert a strong influence on land use change of the region,leading to severe shortage of natural resources.The results indicate that water resource confines the enlargement of urban land use to some extent.The normal increment without water restriction is 40.42-63.38km2,under water restriction is 21.21-51.30km2.The total urban land use of the former to the whole area is 22%-25% and that of the latter,20%-24%,indicating that restricted scenario is far lower than that without restriction.Especially the average increment rate of the fervent-restricted scenario is only 21.21km2,that is 37.6% of the weak-restricted scenario and 33% of the rapid-developing scenario without water restriction.Moreover,it needs to point out that the less the amount of water resource is,the more significant the influence of water resource on land use change.With the speedup of urbanization and the further economic development in Beijing,the limitation of water resources to Beijing's development is becoming more and more obvious.
Research on Land Surface Thermal-Hydrologic Exchange in Southern China under Future Climate and Land Cover Scenarios  [PDF]
Jianwu Yan,Baozhang Chen,Min Feng,John L. Innes,Guangyu Wang,Shifeng Fang,Guang Xu,Huifang Zhang,Dongjie Fu,Huimin Wang,Guirui Yu,Xiaomin Sun
Advances in Meteorology , 2013, DOI: 10.1155/2013/969145
Abstract: Climate change inevitably leads to changes in hydrothermal circulation. However, thermal-hydrologic exchanging caused by land cover change has also undergone ineligible changes. Therefore, studying the comprehensive effects of climate and land cover changes on land surface water and heat exchanges enables us to well understand the formation mechanism of regional climate and predict climate change with fewer uncertainties. This study investigated the land surface thermal-hydrologic exchange across southern China for the next 40 years using a land surface model (ecosystem-atmosphere simulation scheme (EASS)). Our findings are summarized as follows. (i) Spatiotemporal variation patterns of sensible heat flux (H) and evapotranspiration (ET) under the land cover scenarios (A2a or B2a) and climate change scenario (A1B) are unanimous. (ii) Both H and ET take on a single peak pattern, and the peak occurs in June or July. (iii) Based on the regional interannual variability analysis, H displays a downward trend (10%) and ET presents an increasing trend (15%). (iv) The annual average H and ET would, respectively, increase and decrease by about 10% when woodland converts to the cultivated land. Through this study, we recognize that land surface water and heat exchanges are affected greatly by the future climate change as well as land cover change. 1. Introduction Global climate change characterized by global warming has put significant impacts on natural ecosystems and human society [1, 2]. According to estimates, global climate will very likely continue to become warm in the next 100 years [3]. Many observed natural and biological systems’ abnormal changes, such as species extinction, sea level rising, and frequent extreme weather events, as well as changes in plant and animal biological characteristics, have been linked to climate warming [4, 5]. Therefore, a reasonable estimate of future climate change has become an important issue for scientists, public, and policy makers and a hot topic for improving the understanding of the climate system and the accuracy of future climate change projections. Climate warming intensifies hydrothermal circulation as well and causes temporal-spatial variations of water and heat resources. It will further increase the frequency of hydrological extreme events and change the regional water and heat balances. In turn, water circulation and heat transport are important processes of each circle in the entire climate system. They directly affect the local climate, environments, and ecosystems and therefore play very important roles in
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