Top PDF Land cover changes and forest landscape evolution (1985–2009) in a typical Mediterranean agroforestry system (High Agri Valley)

Land cover changes and forest landscape evolution (1985–2009) in a typical Mediterranean agroforestry system  (High Agri Valley)

Land cover changes and forest landscape evolution (1985–2009) in a typical Mediterranean agroforestry system (High Agri Valley)

Briefly, all the forest classes increased their extent and have become generally more stable in functions and structure as a consequence of a larger patch size, a higher con- nectedness, a larger distance between similar patches and a more irregular perimeter. This analysis was carried out also taking into account the forest tenure regimes (pub- lic and private) to elucidate some particular aspects arising from the different type of

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Effect of land use land cover changes on carbon sequestration in Germany

Effect of land use land cover changes on carbon sequestration in Germany

(“Indicator: Greenhouse gas emissions | Umweltbundesamt,” n.d.). However, this decrease was not achieved strategically but was partly due to the economic crisis in 2009 which led to many companies cutting down on production. According to the Clean Energy Wire website, in 2007 Germany put in place targets to reduce GHG emissions by 40% by 2020, by 55% by 2030 and up to 95% in 2050, compared to the 1990 levels (“Germany’s greenhouse gas emissions and climate targets | Clean Energy Wire,” n.d.). From this, Germany is going to miss its 2020 target by about 8-9%. As a result, more measures need to be put in place in order to cut even more emissions. There is a need for enhanced strategic reduction of Germany’s GHG emissions. For environmental planning committees in Germany to be able to formulate better policies to achieve the GHG emissions reduction targets, knowledge of where carbon is being stored the most and the least in the landscape is imperative. Corine Land Cover (CLC) maps show the changes in land use over time, therefore they can pinpoint the general changes that have been occurring in each of the individual classes throughout the 28- year period from 1990-2018. In addition, we can also gauge whether these changes have had any effect on the carbon stock levels. All this would prove to be very instrumental towards achieving the set targets, as they would enable the land management committees to formulate policies that emphasize on the need to preserve the existing carbons sinks and replenish any deteriorating ones. This is especially because the necessary energy and infrastructural transformations that were suggested in the Climate Action Plan (CAP) 2050 will likely take a while to implement and for the effects to be felt (Ministry, Conservation, & Bmu, 2018).
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UNIVERSIDADE FEDERAL DE SÃO CARLOS CENTRO DE CIÊNCIAS BIOLÓGICAS E DA SAÚDE

UNIVERSIDADE FEDERAL DE SÃO CARLOS CENTRO DE CIÊNCIAS BIOLÓGICAS E DA SAÚDE

ABSTRACT. Land use trajectory analysis provides both the time and origin of land cover changes to monitor land use dynamics. It was studied land cover change trajectories for three different dates (1965, 1989, and 2014), extracted from satellite imageries by oriented classification method. This study was carried out on a cultural landscape (São Carlos municipality, SP, Brazil), with three major land use-cover classes (forest, agriculture, and other uses). The results showed the spatio-temporal variability of landscape pattern and forest and agriculture changes trajectories. Analysis base on these landscape trajectories demonstrates that agriculture and forest land use-cover changes have been caused by human activities. The results reflect the conflicting interactions between environmental and human systems in the study area. A key question to revert the pressure exerted on forest land use-cover depends on the incentives that move society from conflicting relation with municipal territory. More sustainable landscape transition and trajectory to São Carlos municipality are extremely dependent of the regulatory role of the government through strategies related to the implementation of legally protected areas (Legal Reserves and Areas of Permanent Preservation).
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QUANTIFYING LAND USE/COVER CHANGE AND LANDSCAPE FRAGMENTATION IN DANANG CITY, VIETNAM: 1979–2009

QUANTIFYING LAND USE/COVER CHANGE AND LANDSCAPE FRAGMENTATION IN DANANG CITY, VIETNAM: 1979–2009

From LULC maps in 1979 and 2009, three most changing classes (agriculture, urban and forest) were chosen to compute spatial landscape matrices at class level by means of FRAGSTATS software (Table 5). In Danang city, forestry area presented as the dominance class of landscape because its percentage of total area is largest. The statistic of forestry showed that the percentage of landscape (PLAND) index decreased from 36 to 33.7, while the number of patches (NP) increased from 2363 to 7815 during the whole period from 1979 to 2009. This combination result suggested the breaking up of forestry areas into smaller parcels. This was supported by the largest patch index (LPI - decreased from 29.4 to 28.6) and the mean patch area (AREA_MN – decreased from 26.2 to 7.4). The values of mean shape index (SHAPE_MN) of forestry for the 1979 and the 2009 were over than 1, exposing that the average forestry patch shape was non-square and there was no significant difference in shape index values.
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EVOLUTION OF CERRADO VEGETAL COVER ON A RIVER ISLAND BASED ON ORBITAL IMAGING DATA

EVOLUTION OF CERRADO VEGETAL COVER ON A RIVER ISLAND BASED ON ORBITAL IMAGING DATA

Low separability values, in general, indicate the relevance of grouping same class samples (MISHRA et al. 2015; LIESENBERG et al., 2007; BITENCOURT et al., 1997). Conversely, the low separability between rough savanna and bare soil, found here, had no effect on separation visualization in land cover map (Figure 3), being afterwards confirmed in the field. MISHRA et al. (2015) studied savanna landscape units in Africa and found low separability between shrubby vegetation and bare soil; however, a good distinction was displayed on the maps, and later confirmed in situ. These authors also stated that a structural similarity between both units resulted in lower spectral separability. Therefore, in our study, we decided not to group the Rough savanna and bare soil classes.
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Analysis of Changing Land Use Land Cover in Salinity Affected Coastal Region

Analysis of Changing Land Use Land Cover in Salinity Affected Coastal Region

Anthropogenic activities have induced many changes in land use over a period of three decades in a salinity affected semi-arid region of coastal Saurashtra in Gujarat. To overcome water scarcity and quality issues, efforts have been undertaken by state authorities to conserve and effectively use surface water resource to supplement the irrigation and domestic water requirements. Surface water schemes implemented in the area have altered the general land use conditions. In the present study, remotely sensed data coupled with ancillary data are used for analysing the land use-land cover change. Supervised classification and post classification techniques are employed to classify various land use-land cover classes and to detect changes, respectively. Landscape pattern change has been studied by analysing the spatial pattern of land use land cover classes structure. The results show that the region has experienced significant changes over a thirty year period. Growth in agricultural activities, policies developed to conserve freshwater runoff, and increase in built-up area, are the main driving forces behind these changes.
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Impacts of changes in land use and land cover on atmospheric chemistry and air quality over the 21st century

Impacts of changes in land use and land cover on atmospheric chemistry and air quality over the 21st century

Hudman, R. C., Jacob, D. J., Turquety, S., Leibensperger, E. M., Murray, L. T., Wu, S., Gilliland, A. B., Avery, M., Bertram, T. H., Brune, W., Cohen, R. C., Dibb, J. E., Flocke, F. M., Fried, A., Holloway, J. S., Neuman, J. A., Orville, R., Perring, A., Ren, X., Sachse, G. W., Singh, H. B., Swanson, A., and Wooldridge, P. J.: Surface and lightning sources of nitrogen oxides over the United States: magnitudes, chemical evolution, and outflow, J. Geophys. Res., 112,

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Nonparametric tests for stationary analysis in hydrological data

Nonparametric tests for stationary analysis in hydrological data

One of the main problems for water resources management systems has been the climate change and the intensification of anthropogenic activities in river basins. In this context, this work aimed to analyze the dynamics of land use and cover and its influence on temporal variability on streamflow data. The behavior of hydrological data (streamflow and rainfall) over time was analyzed by applying the nonparametric tests of Mann Kendall and Pettitt. Images derived from orbital sensors using the Random Forest classifier assessed the anthropogenic influence in the area, land use, and cover classification. The rainfall data did not present significant changes over time, according to the applied tests. However, the low annual flow and average annual flow presented nonstationary behavior, with a trend of reduction over time. As rainfall did not change in its patterns over time, the main reason associated with the changes in streamflow regimes was associated with the changes in land use and land cover, especially in the areas for crops, that had an increase of 48% in the study period, which can contribute to increase the demand for water and affect the streamflow. The results obtained confirm the importance of this study for water management systems to adapt itself to the changes in hydrological behavior over time.
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Land cover changes affect soil chemical attributes in the Brazilian Amazon

Land cover changes affect soil chemical attributes in the Brazilian Amazon

Therefore, the scientific community has agreed that fighting against Amazon deforestation is a matter of national security (Machado, 2009; Sawyer, 2009). Thus, promoting the conservation of natural resources combined with sustainable socio-economic and environmental development will contribute to minimizing this situation (Foley et al., 2007). The establishment of forest plantations enhances forest regeneration (Sansevero, Prieto, Moraes, & Rodrigues, 2011). This fact is a consequence of the attraction of birds, which are seed dispersal agents, and the amelioration of severe microclimate conditions by the recovery of plants in the soil, which facilitates the establishment of seedlings (Meli & Dirzo, 2013). Moreover, the presence of a dense root system contributes to the control of soil erosion and to the input of soil organic matter and nutrients through litterfall (Chada, Campello, & Faria, 2004).
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EFEITOS DA EXPANSÃO URBANA NA CONSERVAÇÃO DE FLORESTAS EM UMA ÁREA DE MANANCIAL METROPOLITANO

EFEITOS DA EXPANSÃO URBANA NA CONSERVAÇÃO DE FLORESTAS EM UMA ÁREA DE MANANCIAL METROPOLITANO

The analysis of the historical changes in land use and cover in the water source area of the Billings Reservoir in Diadema revealed that deforestation in the last five decades is directly associated to urban sprawling in the municipality, resulting in great damage to the local conservation of the Atlantic Forest. Consequently, there is a clear trend towards even further reductions in quantity, quality, and connectivity of forest fragments, which can have adverse effects on water availability and quality of the reservoir and be a potential threat to the survival of local native species. Reversing this scenario depends on changes in planning and management aimed at ensuring the maintenance of the remaining forest remnants, as well as incentives to viable alternatives for restoring the native vegetation. The main scientific contribution of our study is to demonstrate the utility of assessment methods of forest conservation to understand the effects of the urban expansion densely populated in water source areas with irregular occupations, and their potential to be applied in landscape planning and management. The main challenge of this methodological application, however, is the lack of historical geospatial data and in-depth studies about the effects of urbanization on the conservation of biological diversity, especially of the species and ecological groups that occur in this region.
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RELATIONSHIP BETWEEN LANDCOVER PATTERN AND SURFACE NET RADIATION IN AN COASTAL CITY

RELATIONSHIP BETWEEN LANDCOVER PATTERN AND SURFACE NET RADIATION IN AN COASTAL CITY

Taking Xiamen city as the study area this research first retrieved surface net radiation using meteorological data and Landsat 5 TM images of the four seasons in the year 2009. Meanwhile the 65 different landscape metrics of each analysis unit were acquired using landscape analysis method. Then the most effective landscape metrics affecting surface net radiation were determined by correlation analysis, partial correlation analysis, stepwise regression method, etc. At both class and landscape levels, this paper comprehensively analyzed the temporal and spatial variations of the surface net radiation as well as the effects of land cover pattern on it in Xiamen from a multi-seasonal perspective. The results showed that the spatial composition of land cover pattern shows significant influence on surface net radiation while the spatial allocation of land cover pattern does not. The proportions of bare land and forest land are effective and important factors which affect the changes of surface net radiation all the year round. Moreover, the proportion of forest land is more capable for explaining surface net radiation than the proportion of bare land. So the proportion of forest land is the most important and continuously effective factor which affects and explains the cross-seasonal differences of surface net radiation. This study is helpful in exploring the formation and evolution mechanism of urban heat island. It also gave theoretical hints and realistic guidance for urban planning and sustainable development.
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Surface albedo in different land-use and cover types in Amazon forest region

Surface albedo in different land-use and cover types in Amazon forest region

One of the biophysical parameters influenced by the modification of original vegetation in forested regions is the surface albedo, which is the fraction of incident radiation reflected by a surface that acts as a factor for distribution of solar radiation and energy flow between the surface and atmosphere (Wang et al . , 2006; Novais et al., 2015). Albedo is a parameter that varies both spatially and temporally given changes in surface properties, such as soil moisture and vegetation cover as well as changes in local natural light conditions (Franch et al., 2014). It influences the prediction of variables like near-surface temperature and relative humidity (Boussetta et al., 2015). Studies relating landscape features to land cover transformation may help in the understanding and planning of changes in landscape conditions over time, including projections of future land use as well as comparisons between alternative landscape scenarios (Paudel and Yuan, 2012; Swann et al., 2015).
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Have historical land use/land cover changes triggered a fire regime shift in central Spain?

Have historical land use/land cover changes triggered a fire regime shift in central Spain?

Second, the expansion of urbanization and new housing developments have had a strong impact on LULC change since the 1970s. In particular, urban sprawl in the most densely populated areas is creating the most challenging territories at risk, namely wildland–urban interfaces [45–47]. A third main general trend is energy transition, consisting in the substitution of biomass fuel (i.e., firewood, charcoal) by fossil fuel, in connection with the industrialization process that implied rural exodus to urban areas [48–51]. This phenomenon has led to the abandonment and quick regeneration of broad woodland areas in many Mediterranean regions during the second half of the 20th century, with obvious implications for the fire regime. In this context, the re-organization of land management systems is a forth driver of radical LULC changes at the local level, with strong multiscale implications for the fire regime. The new land management systems are (i) a reaction to the privatization of woodlands and to the introduction of the Forest Regime in the 19th century and (ii) the adaptation to rural area depopulation and to new market demands. Last but not least, the new sociopolitical organization introduced by the modern political system in the 19th century and the widespread urban lifestyle since the mid-20th century are not only a driving force of LULC changes, but they are also at the origin of a cultural shift. Paradoxically, growing technological and economic modernization has brought about a higher fire risk, which is particularly evident at the local scale.
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Effects of forest harvesting on summer stream temperatures in New Brunswick, Canada: an inter-catchment, multiple-year comparison

Effects of forest harvesting on summer stream temperatures in New Brunswick, Canada: an inter-catchment, multiple-year comparison

This paper presents a pre- and post-harvest comparison of stream temperatures collected in five neighbouring streams (sub-catchments) over a period of five years (1994-1998). The aim of the study was to determine whether land cover changes from clear cutting in areas outside forest buffer zones (applied to streams >0.5 m wide) might contribute to an increase in summer mean stream temperatures in buffered streams downslope by infusion of warmed surface and sub-surface water into the streams. Specific relationships were observed in all five forest streams investigated. To assist in the analysis, several spatially-relevant variables, such as land cover change, mid-summer potential solar radiation, flow accumulation, stream location and slope of the land were determined, in part, from existing aerial photographs, GIS-archived forest inventory data and a digital terrain model of the study area. Spatial calculations of insolation levels for July 15 th were used as an index
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How old is the Tasmanian cultural landscape? a test of landscape openness using quantitative land-cover reconstructions

How old is the Tasmanian cultural landscape? a test of landscape openness using quantitative land-cover reconstructions

Proponents of the former model interpret the region-wide domi- nance of rain forest pollen types as indicating a climate-driven expansion of rain forest from the Late Pleistocene to the mid-Holo- cene (e.g. Colhoun, 1996; Macphail, 1979). In contrast, Fletcher and Thomas (2007a,b, 2010a,b) highlight the bias in the pollen record towards plants that produce large amounts of well-dispersed pollen (i.e. rain forest species in Tasmania), and use modern pollen spectra to infer the persistence of open vegetation across western Tasmania for the last c. 12,000 years (12 kyr). They note a departure between Holocene and previous interglacial floras and charcoal sequences, citing human arrival during the last glacial cycle ( ~35 kyr) as the probable cause for this, thus concluding that western Tasmania rep- resents an ancient cultural landscape. Macphail (2010) has critiqued their model, arguing that the nature of pollen deposition at many of the mires studied by Fletcher and Thomas (2010a) biases pollen records towards local bog vegetation, which is palynologically similar to pyrogenic moorland. Thus, the debate over the origin and devel- opment of the modern treeless and pyrogenic vegetation landscape of western Tasmania centres on how pollen production and deposi- tion biases are resolved.
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Historical land-use induced evapotranspiration changes estimated from present-day observations and reconstructed land-cover maps

Historical land-use induced evapotranspiration changes estimated from present-day observations and reconstructed land-cover maps

Teuling, A. J., Seneviratne, S. I., Stöckli, R., Reichstein, M., Moors, E., Ciais, P., Luyssaert, S., van den Hurk, B., Ammann, C., Bernhofer, C., Dellwik, E., Gianelle, D., Gielen, B., Grün- wald, T., Klumpp, K., Montagnani, L., Moureaux, C., Sottocornola, M., and Wohlfahrt, G.: Contrasting response of European forest and grassland energy exchange to heatwaves, Nat. Geosci., 3, 722–727, doi:10.1038/ngeo950, 2010.

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Ecological risk assessment based on land cover changes

Ecological risk assessment based on land cover changes

In recent years, the ecological and environmental impacts caused by land transformation have been reported to grow at a very rapid rate and are considered to be a major problem around the globe [1,2]. These impacts are connected with the exploitation of natural resources, destruction of biodiversity as well as disturbing the ecosystem structure that offers essential services to mankind including nutrient cycling, pollination, predator control, carbon sequestration, and soil fertility [3]. According to [4], Africa and Asia are the areas with the highest ecological problems caused by land use and land cover (LULC) changes. The drivers of LULC changes such as overpopulation, improper control of land resources, together with poor economic situations have made these regions highly affected by ecological problems [5]. For instance, [6] showed that between 1975 to 2000, more than 16% of forest cover and 5% of woodland and grassland had been destroyed on the African continent. In East Africa including Zanzibar, 48% of the tree cover was destroyed from 1986 to 2015 due to the rapid rate of deforestation and expansion of casual agricultural activities [7]. Most of this destruction was attributed to the threat of an extremely limited number of natural resources, impairing agricultural lands, rising in irregular and unreliable urban areas as well as increasing in landscape fragility and ecological shock [8].
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Land cover change in Colombia: surprising forest recovery trends between 2001 and 2010.

Land cover change in Colombia: surprising forest recovery trends between 2001 and 2010.

highest rates of woody vegetation loss. These areas have had extensive areas of natural savanna vegetation transformed to crops and pastures during the past 20 years [64,67]. We suggest that a primary conservation goal in Colombia should be the implemen- tation of protected areas in these regions. The Llanos ecoregion is particularly important given its heterogeneous landscapes, its high diversity of vegetation types, and its large numbers of plants, amphibians, reptiles, and fish [75]. Not surprisingly, this ecoregion has been cataloged within the Global 200, which is a set of the most outstanding ecoregions for global conservation [75]. In addition, the Apure-Villavicencio dry forest should be taken into account in the protected areas network because it represents the transition zone between the Andean foothills and the llanos savannas where a relatively high number of plant, reptile, and bird species (including several endemics) coexist (See http://www. worldwildlife.org/wildworld/profiles/terrestrial_nt.html# trop- grass). We also documented a large decrease in mixed woody/plant in the Magdalena-Uraba´ Moist forest ecoregion, particularly in the Magdalena Medio region. The increase in agriculture and pastures combined with ongoing illegal logging activities [70,76] have endangered a great number of native timber species (e.g. Libidibia ebano, Cariniana pyriformis). This region should be considered for the protected area network given that there is only one reserve (Serranı´a de los Yariguı´es national park) in this region. On the other hand, the recovery of woody vegetation in the Andes Mountain Ranges is an excellent opportunity to comple- ment, expand and interconnect the protected areas to create a conservation network across the rural landscape mosaics in the region. A relevant area for conservation is the Northern Andean Montane Forest ecoregion, which is also included in the Global 200 [75]. In this ecoregion, the Cundiboyacense highplain had a substantial and significant gain of woody vegetation between 2001 and 2010. Other authors have stressed the importance of this region as a priority area for conservation due to its large areas of land transformation and large number of species at risk [74]. We also highlight that even though the Northern Andean Pa´ramo ecoregion gained slight amounts of woody vegetation, the gains in the ag/herb class were almost three times higher than woody cover gains, and therefore, the Andean Pa´ramos remains a threatened ecosystem.
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Analysis Land use and Land cover changes and the driving forces

Analysis Land use and Land cover changes and the driving forces

In fact, the economic and urban development over last decades in the district has influenced land resource demands and land concession widely, which is also causing a problem in land use management and planning in the district (Luanglatbandith, 2007). According to ADB (2012), the core problem in urbanization of Kaysone Phomvihan district is taking place with minimal coordination, inadequate infrastructure and insufficient concern for environmental impacts. This results in disorganized growth, inefficient land use, damage and loss of natural resources and inadequate access to urban services. These problems can be attributed to poor urban management, and spatial planning, poor connectivity between urban planning and environmental management, and insufficient investment in infrastructure and community services. Understanding land use patterns and changes as a major importance in this context. Since, accurate and timely information of land use change is highly necessary to many related spatial planning sectors and actors for estimating levels and rates of deforestation, urbanization, wetland and soil degradation and many other landscape-level phenomena (Vogelmann et al., 2001).
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SPATIO-TEMPORAL LAND USELAND COVER CHANGES ANALYSIS AND MONITORING IN THE VALENCIA MUNICIPALITY, SPAIN

SPATIO-TEMPORAL LAND USELAND COVER CHANGES ANALYSIS AND MONITORING IN THE VALENCIA MUNICIPALITY, SPAIN

Now a day, urbanization has become an environmental problem of global importance. Despite the few percentage distribution and coverage of geographic space of urbanized land, the impacts of the process of urbanization on biodiversity, ecosystem fluxes and environmental quality are profound and these days it gets much attention by scholars from diverse fields, (Breuste, et al., 1998; Pickett, et al., 2001). Urban growth affects the ecology of cities in a number of ways, such as eliminating and fragmenting native habitats, modifying local climate conditions and generating anthropogenic pollutants. It is widely recognized that the spatial pattern of a landscape affects ecological processes (Wu and Loucks, 1995). Similarly, tremendous urban expansion with high inflow of population from the local or distant places and dynamic urban changes processes in their morphology, expansion of impervious surface and conversion of productive lands in and around urbanized area, affect natural and human systems at all geographic scales. Deteriorating conditions of urban crowding, housing shortages and lack of infrastructure, as well as increasing urban expansion on fertile lands highlights much attention for sustainable and effective management and planning of urban areas. Recently, innovative approaches to urban land use planning and management such as sustainable development and smart growth has been proposed and discussed (Kaiser, et al., 1995).
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