Vegetation and land use

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Land use changes and vegetation dynamics in a silvopastoral system : effect on their ecological structure and carbón storage

Land use changes and vegetation dynamics in a silvopastoral system : effect on their ecological structure and carbón storage

The landscape in the old agricultural border in Nicaragua is a fragmented matrix in a livestock environment involving many different land uses with different tree cover and carbon storage. The municipality of Matiguás is a representative area of the livestock landscape in the sub-humid tropics. In order to assess land use and land cover (LULC) changes in Matiguás, the most representative traditional silvopastoral systems (TSPS) in the area were selected: shrubland, intervened secondary forest, pasture with high tree density, pasture with low tree density and degraded pasture. As an alternative to monitor and quantify these changes, remote sensing was used. In the last two decades, before Landsat images were free, developing countries could not afford monitoring through remote sensing because of the high cost of acquiring satellite imagery and commercial software. However, Landsat time series nowadays allows the characterization of changes in the vegetation across large areas over time. Nearly cloud free Landsat scenes: A Landsat 5 Thematic Mapper scene from 1986 and a Landsat 8 OLI scene from 2015 have been the datasets used in the study. A process chain following Jensen’s (2009) four-step definition of the remote sensing process was conceptually developed and implemented, based on free open source software components and by applying the Random Forest algorithm. A conceptual LULC classification scheme representing TSPS was developed. Although the imagery shows a heterogeneous surface cover and mixed pixels, it was possible to achieve promising classification results with out-of-the bag errors below 13% for both images along with an overall accuracy level of 85.9% for the 2015 subset and 85.2% for the 1986 subset. The classification shows that from 1986 to 2015 (29 years) the intervened secondary forest increased 2.6 times while the degraded pasture decreased by 34.5%. The livestock landscape in Matiguás is in a state of constant transformation, but the main changes head toward the positive direction of tree cover recovery and an increase number of areas of natural regeneration.

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Climate and vegetation structure determine plant diversity in Quercus ilex woodlands along an aridity and land use gradient in Northern Algeria

Climate and vegetation structure determine plant diversity in Quercus ilex woodlands along an aridity and land use gradient in Northern Algeria

major environmental factors. Species composition is expressed as coordinates of the sample plots. Symbols (both, full and empty) indicate plots, crosses indicate species and arrows indicate environmental factors. The smoothing surface lines (Oksanen et al., 2010) for mean annual precipitation are shown in grey.

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Land useland cover change and extreme climatic events in the arid and semi-arid ecoregions of Mexico

Land useland cover change and extreme climatic events in the arid and semi-arid ecoregions of Mexico

The TC is a semi-arid region of central Mexico, rec- ognized as a major reservoir of biological diversity (Dávila et al., 2002). The dominant land use in this ecoregion is agriculture (Figs. 2, 4). Our findings in the TC agree with a study published by Valiente-Ba- nuet et al. (2006), who found an intensification in forest exploitation and agricultural and livestock production occurring along the TC, resulting in overexploitation of specific resources and progres- sive degradation of vegetation and agricultural lands, as well as the quality of life in rural communities. Also Moreno-Calles (2010) concludes in a research on agroforestry systems in the TC that both ecosys- tems and productive activities are at risk because of intensification of agriculture resulting in a loss of both vegetation cover and plant diversity, as well as soil and economic migration influencing cultural and land use changes. In comparison with the rest of arid and semi-arid ecoregions, municipalities in the TC ecoregion have the lowest exposure to ECE (Fig. 6), but decreasing trends in mean maximum and mini- mum temperatures have been detected in the northern portion of the ecoregion, accompanied by decreases in precipitation in the south/southeastern portion but increases in the north, which in turn has translated into a cooler and wetter northern portion (Table III). Trends in temperature and precipitation are not clear for the southern portion of this ecoregion, although there is mention of an increase in both the frequency and intensity of extreme rainfalls events in southern Mexico, where this ecoregion is located (Peralta-Hernández et al., 2009). Considering that this area is mainly dedicated to agriculture, precip- itation parameters should be monitored closely due to its importance for this activity. Surprisingly, there are several gaps of information for this ecoregion

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Characterizing the relationship between land use land cover change and land surface temperature

Characterizing the relationship between land use land cover change and land surface temperature

To better understand the detailed relationship between LST and LULC, a regression model for each LULC type was constructed. The correlation between NDVI, NDBI and LST within each LULC type showed some important results. First, a general trend was seen in urban LULC in the sense that all urban LULC types were negatively correlated with NDVI and positively correlated with NDBI. This highlighted an important conclusion about the incontrovertible role of vegetation in mitigating UHI. Urban design that considers vegetation partitions would help to regulate the thermal environment (Qiao et al., 2013). City planners and policy makers should take seriously into account the "greening strategy" as it may be the most effective solution for reducing the UHI effect within a city. Nevertheless, it was discovered that water had a positive effect in relation to both NDBI and NDVI. It means mixed water with more vegetation and built-up materials (sand, gravel, soil, or rubbish) will have higher LST. We assume that polluted water might negatively contribute to the UHI effect. Therefore, further study may be needed to quantify the relationship between water quality and UHI. .

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CAMBIOS DE VEGETACIÓN Y USO DE SUELO EN LA CUENCA RÍO BRAVO-SAN JUAN, COAHUILA (1993 A 2008)

CAMBIOS DE VEGETACIÓN Y USO DE SUELO EN LA CUENCA RÍO BRAVO-SAN JUAN, COAHUILA (1993 A 2008)

Loss of natural soil cover affects the biosphere, it damages both biotic and abiotic elements: soil, rock bed, topography, and water bodies (Oyinloye et al., 2004). Loss of vegetation cover is considered a stage in the process of environmental and natural resources degradation (Bocco et al., 2001). Most alterations in plant cover fit into one of three categories: 1) conversion of one vegetation type to another; 2) degradation; 3) land use intensification (Lambin, 1994). These alterations may be natural or human induced. Hurricanes, wildfire, volcanic eruptions, and drought are examples of natural causes. Man caused changes involve effects from socioeconomic activities, and consequences of demographic policies affecting agriculture, animal production, industry, and urbanization (Bocco et al., 2001; Lambin et al., 2001; Vitousek et al., 1997).

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Spatial patterns over a 24-year period show an increase in native vegetation cover and decreased fragmentation in Andean temperate landscapes, Chile

Spatial patterns over a 24-year period show an increase in native vegetation cover and decreased fragmentation in Andean temperate landscapes, Chile

Exotic tree plantations also increased in the area. Unlike native vegetation recovery, the increase of exotic tree plantations is also observed at the regional level. In the La Araucanía Region, exotic tree plantations increased by 62.9% between 1993 and 2007 (CONAF, 2009). The 37.1% increase in exotic tree plantations in our study area is lower than the regional trend. However, we also observed the appearance of mixed forest (exotic with native) patches. According to Lara et al. (2012), exotic tree plantations have been the second cause of native forest replacement in the La Araucanía Region. The 1974 Law Decree 701 established economic incentives to afforestation (Niklitschek, 2007), and after the implementation of this decree, exotic species have been extensively planted for pulp and wood production in south-central Chile. In the study area, the increase in exotic tree planta- tion is due to the presence of new, small patches rather than the expansion of existing plantations. This suggests that exotic tree plantations may be used as a complementary economic activity rather than a main productive land use. Further studies are required to understand the role of exotic tree plantations in a multifunction landscape. The large percent increase in residential area (670.26%) is not surprising because the county showed the highest population growth rate in the Region between 1982 and 2002 (INE, 2008). The increasing residential use of the landscape is likely associated with tourist activity in the area because some residential patches correspond to secondary residences. The natural appeal of the area has generated the development of the tourism industry, thereby increasing the number of vacation houses and private protected areas. Further, Hidalgo and Zunino (2011) reported that over the last 10 years, new residents have arrived in Pucón searching for spiritually oriented and natural livelihoods. The increase in population and settlements implies a growing human presence in the area but also suggests a greater concern

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Future emerging waterborne zoonosespdf, 104kb

Future emerging waterborne zoonosespdf, 104kb

SARS virus appears to be a new cause of human infections. HEV is newly recognized, but has been implicated retrospectively in hepatitis outbreaks dating back to the 1950s (Jothikumar et al. 1993). Recent studies suggest that there may be a close link between human HEV and swine HEV (chapter 15), and there is new evidence of interspecies transmission of HEV (Meng 2003). Some of these emerging pathogens may actually be new viruses that may have evolved through random genetic changes in the genomes of animal viruses that allowed them to bind and enter human host cells. RNA viruses (SARS, coronavirus, HEV, rotavirus A, and noroviruses) are known to have high mutation rates during replication in host cells. Some bovine and swine norovirus strains are genetically very similar to some human norovirus strains (van Der Poel et al. 2000), suggesting that they evolved from a common ancestor. Other new viral pathogens may have arisen through recombination events where an animal or human becomes co-infected with two different viruses that recombine during replication in the host cell. The new reassortant strain has portions of the genomes of both viruses. Animal rotaviruses have been detected in drinking- water, and other investigators have speculated on the role of water in the spread of animal strains to human populations and the emergence of reassortant strains (Gratacap-Cavallier et al. 2000). Bovine–human reassortant strains have been detected in infants in Bangladesh (Ward et al. 1996) and may possibly have been transmitted from humans to cows or vice versa via faecal contamination of water.

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Urban heat islands in Monterrey, México using remote sensing imagery and geographic information systems analysis

Urban heat islands in Monterrey, México using remote sensing imagery and geographic information systems analysis

The final images selected to perform the analysis were from the year 2009, since this is the most recent one that can be compared with 2003, according to the climatic analysis, 2011 was a year of extreme events (Alex hurricane). The month of May was chosen to perform the analysis, according to the solar radiation graph, which indicates that May, July and August are the months with the highest radiation. Since July and August are already rainy months it is difficult to obtain a cloud clear image. Results show the localization of heat islands. One heat island is located in a lineal form along Colón and Madero avenues, and it extends north around Parque Niños Héroes. Another lineal formation is along Lincoln and Ruiz Cortinez avenues. Also, heat concentrates north the Metropolitan Area of Monterrey, along Río Pesquería. Finally, there is another heat island west Santa Catarina, and through the Huasteca. It is important to mention that there are isolated heat points, mostly in parking lots of commercial zones.

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Modelling land use and transport policies to measure their contribution to urban challenges: the case of Madrid.

Modelling land use and transport policies to measure their contribution to urban challenges: the case of Madrid.

support strategic urban planning [8]. Lowry Model of Metropolis [43] was the first attempt to quantify the land use transport feedback cycle in a single integrated model. After the Lowry Model, many spatial interaction location tools have been developed, aiming at modelling the location of human activities as origins and destinations of trips, e.g., METPLAN [44] and PECAS [45]. Other LUTI models do not predict actual spatial interactions but the opportunity for spatial interactions are expressed as accessibility. Compared to the first urban models, which were static equilibrium models, accessibility-based location models, such as INPUD [46], MUSSA [47], DELTA [48] and MARS, tend to be more dynamic, attempting to capture the dynamics of urban processes. Sheperd [10] suggested applying the dynamic approaches in LUTI models. He argued that the land use and transport systems interact at different time scales. The land use changes are much slower than transport changes. These time lags and the complex interactions between them offer an ideal situation for the implication of the system dynamic approaches. Shepherd [10] highlighted the MARS model among others, due to its validation and transferability between cities. The model has already been applied to more than 20 cities around the world [49].

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NATIONAL REPORT ON THE IMPLEMENTATION OF THE RAMSAR CONVENTION ON WETLANDS National Reports to be submitted to the 13

NATIONAL REPORT ON THE IMPLEMENTATION OF THE RAMSAR CONVENTION ON WETLANDS National Reports to be submitted to the 13

To contribute to the global environmental protection effort, the Government of Yemen has ratified UNCBD, UNCCD & UNFCCC and is party to a number of relevant international conventions and regional protocols, including the CITES, Hazardous Wastes, Law of the Sea and Ozone Layer Depletion, RAMSAR Convention, World Heritage Convention, and Bonn Convention, which make some provision for meeting global environmental objectives. By ratification of these conventions, the GoY assigned the EPA as a Government agency responsible for monitoring compliance with obligations made under international conventions such as the UNCBD and the UNFCCC. The EPA in this capacity hosts the secretariat and national implementation units of most of GEF/UNDP projects currently ongoing in Yemen, such as the Biodiversity planning, the Climate Change Enabling and the Socotra projects among others. In its capacity as national focal points for UNCBD and UNFCCC, the EPA has been engaged in conservation of biodiversity resources through the initiation and development of several legal and technical activities and improving environmental coordination based on its mandates and the Environmental Protection Law No. (26) for 1995 (EPL). This effort has led to the establishment of EPA board of directors to act as coordinating body for Climate Change, biodiversity, Land Degradation, etc. The current structure of the board of directors include representatives from the Environment Protection Authority (EPA) of the Ministry of Water and Environment (MoWE), the Ministry of Agriculture and Irrigation, the Ministry of Fish Wealth, the Ministry of Planning, the Ministry of Electricity, the Water Resources Authority, and the Ministry of Local Administration. Unfortunately, the board had no role in the production of the NBSAP2 and rarely met and thus it needs to be activated, its structure reformed and given stronger mandates, including the removal of overlapping responsibilities amongst environmental partners.

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Analysis of urban land use and land cover changes: a case study in Bahir Dar, Ethiopia

Analysis of urban land use and land cover changes: a case study in Bahir Dar, Ethiopia

Land use change models such as LCM provided an important spatio-temporal information of land use and land cover changes especially on urban areas. It also provide the possibility to understand the influence of urban dynamics supported by a set of drivers. Model results have shown remarkable changes in built up areas between the study periods. The accuracy of MLP to generate transition potential maps has got an acceptable value of 61%. Simulated results of 2010 quantified that much of agricultural land had been converted in to built up areas regardless of the driving factors which have negative impacts on the simulation process. Although the accuracy of MLP was good to model transition potential maps, simulated results using Markov chain showed visible differences with the actual land cover map of 2010. Validation results based on total disagreements (quantity and allocation disagreement) showed that the model, LCM, performed a total disagreement of 13% and considered as a lower performance. Validation using a three map comparison also confirmed that LCM showed a lower accuracy in predicting land use changes (hits) correctly in this study area (Bahir Dar area).

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Classifiers ensemble in remote sensing: a comparative analysis

Classifiers ensemble in remote sensing: a comparative analysis

If we have in consideration that many ensembles work better than a single classifier, we should think that the variation that different algorithms add to the whole system must be positive. Under our perspective, two problems appear, when we deal with the concept diversity, the thresholds and the measures. Obviously, it seems clear that certain degree of variance between the elements of an ensemble will give to it more power to predict, but which are these thresholds within the diversity, where the ensemble gain strength. As an example, two completely different algorithms that produce extremely different outputs do not create a powerful ensemble, but the contrary. Hence, how much different should be the algorithm between them within the ensemble is still a mystery.

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Brief examinations of selected FBCN’s hands-on projects provide an idea of how conservationist and effective it was. An early FBCN-supported project, initiated in 1967, was archaeological in nature. However, it was focused on the recently created Tijuca National Park, located in Rio, and sought to inform visitors about the area’s history. It was supported also by CNPq (Brazil’s national science foundation) and IBDF, the agency responsible for the park. For more than 25 years FBCN member Carlos Manes Bandeira (1931-1993) and several teams of historians, architects, museologists and interns researched parklands extensively. Bandeira’s teams unearthed at least 86 remains of farmhouses, slave dwellings, trails, warehouses, waterworks and fountains, besides artefacts (clocks, pottery, silverware, stoves, furniture, pens, tools) belonging to coffee farms that once covered the area. Thousands of objects were retrieved, restored and identified. Sites were described in dozens of reports. FBCN planned to display these materials in a "Coffee Farms Museum" to be installed inside the park. The educational potential of this work is enormous. Nowhere else in Rio can the general population and visitors learn about the city's coffee farm past. 33

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Climatic analysis linked to land vegetation cover of Mexico by applying multivariate statistical and clustering analysis

Climatic analysis linked to land vegetation cover of Mexico by applying multivariate statistical and clustering analysis

The relationship between climate and vegetation distribution has been used to make inferences about changes in the behavior patterns of both components. The classification of climatic regions can contribute to the knowledge about climate change and the po- tential distribution of vegetation (Bonan et al., 2003). There has been a climate typing attempt to introduce a series of rules in order to generate climatic region- alization based on the statistical analysis of long-term meteorological data. One of these statistical analyses, based on eigen techniques, represents an alternative that can be used to generate reproducible climatic maps (Richman, 1981). The climatology of Mexico has been described by some authors (García, 2004; Comrie and Glenn, 1998; Englehart and Douglas, 2002; Giddings et al., 2005, Bravo et al., 2012). However, for new methodologies to be introduced, it is indispensable to understand climatic zoning based on statistical data analysis. When defining climate regions, typically, long-term monthly means are employed from a set of climatic observations (tem- perature and precipitation) regarding a number of climatic stations (Pineda-Martínez et al., 2007). The principal aim of this research is to apply a hierarchical clustering analysis to historical meteorological data of Mexico.

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The spatial dynamics of land use surrounding the Spanish property bubble (1990 2012)

The spatial dynamics of land use surrounding the Spanish property bubble (1990 2012)

previous dynamics of Spanish land development, this method confirms the importance of the metropolitan or coastal-tourism dynamics, but with several notably new features: the enormous development in Madrid (5) and, Toledo, collaterally (5) which contrasts with Barcelona or Vizcaya (Biscay) (0) and, in general, the lower development of the rest of the traditional metropolitan areas, all below grade 2, except Zaragoza (3). Regarding coastal tourism areas, the development of the southern Mediterranean coastline (Murcia, grade 4, Alicante and Castellon, grade 3) is more significant than that of the Canary Is. and Balearic Is. that formed part of the previous stage. Finally, this method of comparison attributes great prominence to an element that had scarcely been observed before: what occurred in inland Spain: a crown of regional hubs around Madrid, with extremely disproportionate growth (Navarre, grade 4 and Valladolid, grade 3, both regional capitals, and above all, León, Ciudad Real and Salamanca, all ranked grade 4) - even those with very low population figures, such as Soria (4).

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Probabilistic survey and prehistoric patterns of land and resource use in Mendoza province, Argentina

Probabilistic survey and prehistoric patterns of land and resource use in Mendoza province, Argentina

The pattern of lithic raw material use at upland (montane and foothills) versus lowland (plains) sites invites further interpretations of land use and mobility. If the predominance of CCS and obsidian at plains sites -versus that of basalt above 1500 m- is an accurate reflection of prehistoric behavior, it suggests plains activities more often required precision in tool manufacturing and/or sharp cutting edges. The small grain size that makes CCS and obsidian both easy to work and very sharp might have been desirable for the production of small projectiles used to hunt birds and small animals, for fileting fish or harvesting grasses. It is also interesting to note that, among the sites found during survey, the obsidian was most commonly from sources in the Andes, suggesting high mobility or trade. It remains puzzling that prehistoric people seemed to prefer Andean obsidian sources to ones on the plains despite similarities in their quality and abundance, particularly in light of the fact that only the plains sources would have been available year-round (Giesso et al. 2011).

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TRANUS: Integrated Land Use and Transport Modeling System

TRANUS: Integrated Land Use and Transport Modeling System

In order to run the transport model without land use, however, a set of origin-destination trip matrices must be provided, certainly not a trivial matter. In large scale models, such as regional or national, it is not too difficult to estimate origin-destination trip matrices from road-side interviews. The transport model is then used to complete and correct the estimates against traffic counts. This process is made easier because the networks are relatively simple, offering not too many travel options. In several countries such origin-destination estimates are readily available. An urban or metropolitan area is quite a different matter. The network is extremely dense, with many options and a fine mesh of possibilities. This turns road-side interviews worthless, except perhaps for regional access highways. But the possibility of building a set of origin-destination matrices from road-side interviews is definitely off. This is why researchers have turned to home interviews, asking for the origins and destinations of trips.

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Eco morphological effects of large wood in mountain basins, under different level of forest management

Eco morphological effects of large wood in mountain basins, under different level of forest management

of these waterways at the time of sampling were far smaller than those of previous studies, indicating the potential effect of the strong seasonality that characterize Central Chilean fluvial systems. The dominant impacts of salmonids on food web dynamics also likely played a top- down role in the ecological effects of the current study. For example, one observation was that sites with no fish (B2-M, E1-L, E1-M, F1-L and F1-M) had more benthic macroinvertebrates found on exposed rock surfaces (sensu Liboriussen et al. 2005), but this was not measured quantitatively. However, this speaks to the different ways that different levels of the ecosystem respond to the presence or absence of different factors, be they bottom-up (LW addition) or top- down (trout introduction) in nature. Further research into the effects of LW on the linkages with physical and ecological processes and fish metrics during different seasons can help improve our understandings of how LW impacts Chilean headwater streams. Research into upstream- downstream effects will also help uncover how LW additions are carried beyond the level of the intervention.

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Influence of external drivers on water use efficiency and sustainability in agricultural production

Influence of external drivers on water use efficiency and sustainability in agricultural production

This research has been carried out thanks to the funding of the Water Observatory of the Botín Foundation and the CEIGRAM, research centre of the Universidad Politécnica de Madrid (UPM), which supported annual consecutive research in the projects "Extension on the analysis of the water footprint and virtual water trade in Spain", "Water and food security in Spain" and "Water and food security in Latin America". The Water Observatory has as its goal the promotion of innovative, science-based approaches to water management with an interdisciplinary approach. Its members form part of two teams, one based in the CEIGRAM and the other based in the faculty of Geology of the Complutense University of Madrid. Formally established in 2008, the water observatory has contributed to the promotion of research talent and the generation of innovative ideas on water governance and water resources management in Spain. It has also contributed to the public discussion on water management by introducing ground-breaking approaches and serving as a space for discussion and dissemination of such ideas. This has been the main learning experience for this thesis, including the seminars, courses and workshops organized by the Foundation. Chapter 3 was conceptualized in the year 2011 in a collaboration with Embrapa’s researcher A. D. Santiago during his stay as guest researcher at CEIGRAM and concluded after field visits in the year 2013. Chapter 4 is the result of collaboration between the Botín Foundation and El Corte Ingles – and the technological centre for the textile industry AITEX and four additional textile and cellulose fibre producers 1 , which lead to this application of the methodology in their supply

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Dinámica de uso de suelo e índice verde en Poza Rica, Veracruz

Dinámica de uso de suelo e índice verde en Poza Rica, Veracruz

In Mexico, studies such as those by Alanís (2005) in Monterrey (Nuevo León), López (2008) in Mérida (Yucatán), Benavides and Fernández (2012) and Velasco et al. (2013) in Mexico City have confirmed how green areas in cities contribute to social well-being, by promoting a healthy coexistence, which improves the mood of users and reduces aggressive behaviors, crime, negative feelings (fear, anger, depression) and with this intrafamily and community violence. In addition, being public spaces they become meeting points that all groups can access, favoring social inclusion (Bascuñán et al., 2007).

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