RESUMO
Abstract Land use and land cover change are affecting the global environment and ecosystems of the different biospheres. Monitoring, reporting and verification (MRV) of these changes is of utmost importance as they often results in several global environmental consequences such as land degradation, mass erosion, habitat deterioration as well as micro and macro climate of the regions. The advance technologies like remote sensing (RS) and geographical information system (GIS) are helpful in determining/ identifying these changes. In the current study area, changes in carbon stocks, notably in forest areas, are resulting in considerable dynamics of carbon stocks as a result of climate change and carbon sequestration. This study was carried out in the Diamer district of the Gilgit Baltistan (GB) Pakistan to investigate the change in cover change/land use change (particularly Forest Land use) as well as carbon sequestration potential of the forests in the district during almost last 25years. The land cover, temporal Landsat data (level 1, LIT) were downloaded from the USGS EROS (2016), for 1979-1989, 1990-2000 and 2001-2012. Change in land uses, particularly forest cover was investigated using GIS techniques. Forest inventory was carried out using random sampling techniques. A standard plot of size 0.1 ha (n=80) was laid out to determine the tree density, volume, biomass and C stocks. Simulation of C stocks was accomplished by application of the CO2FIX model with the data input from inventory. Results showed a decrease in both forest and snow cover in the region from 1979-2012. Similarly decrease was seen in tree volume, tree Biomass, dynamics of C Stocks and decrease was in occur tree density respectively. It is recommended we need further more like project such as BTAP (Billion Tree Afforestation Project) and green Pakistan project to increase the forest cover, to control on land use change, protect forest ecosystem and to protect snow cover.
Resumo O uso e as mudanças na cobertura da terra estão afetando o meio ambiente global e os ecossistemas das diferentes biosferas. O monitoramento, relatório e verificação (MRV) dessas mudanças são de extrema importância, pois muitas vezes resultam em várias consequências ambientais globais, como degradação da terra, erosão em massa, deterioração do hábitat, bem como micro e macroclima das regiões. As tecnologias avançadas, como sensoriamento remoto (RS) e sistema de informações geográficas (SIG), são úteis para determinar / identificar essas mudanças. Na área de estudo atual, as mudanças nos estoques de carbono, principalmente em áreas florestais, estão resultando em uma dinâmica considerável dos estoques de carbono como resultado das mudanças climáticas e do sequestro de carbono. Este estudo foi realizado no distrito de Diamer de Gilgit Baltistan (GB), Paquistão, para investigar a mudança na mudança de cobertura / mudança de uso da terra (particularmente uso de terras florestais), bem como o potencial de sequestro de carbono das florestas no distrito durante quase os últimos 25 anos. A cobertura da terra, os dados temporais do Landsat (nível 1, LIT), foram baixados do USGS EROS (2016), para 1979-1989, 1990-2000 e 2001-2012. Mudanças nos usos da terra, particularmente na cobertura florestal, foram investigadas usando técnicas de SIG. O inventário florestal foi realizado por meio de técnicas de amostragem aleatória. Um lote padrão de 0,1 ha (n = 80) foi estabelecido para determinar a densidade das árvores, volume, biomassa e estoques de C. A simulação dos estoques de C foi realizada pela aplicação do modelo CO2FIX com a entrada de dados do inventário. Os resultados mostraram uma diminuição na cobertura florestal e de neve na região de 1979 a 2012. Da mesma forma, diminuição foi observada no volume da árvore, biomassa das árvores, dinâmica dos estoques de C e diminuição na densidade das árvores, respectivamente. É recomendado que precisemos de mais projetos como o BTAP (Billion Tree Afforestation Project) e o projeto Green Pakistan para aumentar a cobertura florestal, controlar as mudanças no uso da terra, proteger o ecossistema florestal e proteger a cobertura de neve.
RESUMO
The Cerrado biome covers approximately 20% of Brazil and it is crucial for the Water, Food, Energy, and Ecosystems (WFEE) nexus. Thus, in recent years, large areas of the undisturbed Cerrado have been converted into farmland. In this biome, according to the Brazilian Forest Code, farmers need to keep 20% of native vegetation (Legal Reserves - LRs). By exploring combined and isolated impacts of different scenarios of LR and Protected area (PA) arrangements, this study evaluated the importance of complementarity between LR compliance and the amount of PAs (including Conservation Units - CUs and Indigenous Lands - ILs) to reduce deforestation and conserve native vegetation in the Cerrado. Seven scenarios were investigated: a scenario that considers the current PA and the LR values foreseen in the Native Vegetation Protection Law - NVPL; three scenarios focused on production; and three focused on conservation. Considering the trend of the current scenario, the estimated loss of native vegetation will be 30% (30.6 million ha) by 2070. According to the model simulations, for two periods (2050 and 2070), the LR Elimination scenario (LRE) would cause a greater loss of native vegetation than the PA Elimination (PAE), and as expected, the exclusion of both (PALRE) would provide a greater loss of native vegetation. Native vegetation is concentrated mainly on agricultural properties. Taking our conservation-oriented scenarios as an example of conservation strategies, if there were no financial, practical, political, social or personal constraints, there is no doubt that the CPALRI scenario (Creation of Protected Areas and Legal Reserve Increase) is the best trajectory for conserving biodiversity. Therefore, private properties, through LRs, are essential for efficient planning of land use/cover as they ensure security in the WFEE nexus. The resulting projected scenarios are important to help decision makers in territorial planning and how to arbitrate territorial demands aiming at the rational use of the natural resources of the Cerrado.
Assuntos
Conservação dos Recursos Naturais , Ecossistema , Brasil , Conservação dos Recursos Naturais/legislação & jurisprudênciaRESUMO
Ensuring a sufficient and adequate supply of water for humans and ecosystems is a pressing environmental challenge. The expansion of agricultural and urban lands has jeopardized watershed ecosystem services and a changing climate poses additional risks for regional water supply. We used stream water quality data collected between 2000 and 2014, coupled with detailed precipitation and land cover information, to investigate the effects of landscape composition and short-term precipitation variability on the quality of water resources in the state of São Paulo, Brazil. The state is home to over 45 million people and has a long history of human landscape modification. A severe drought in 2014-2015 led to a major water crisis and highlighted the fragility of the regional water supply system. We found that human-dominated watersheds had lower overall water quality when compared to forested watersheds, with urban cover showing the most detrimental impacts on water quality. Forest cover was associated with a better overall water quality across the studied watersheds, with forested watersheds having low turbidity and high dissolved oxygen. High precipitation led to increased turbidity and fecal coliforms levels and lower dissolved oxygen in streams but these effects depended on watershed land cover. High precipitation diluted concentrations of nitrogen and dissolved solids in highly urbanized watersheds but exacerbated turbidity in pasture-dominated watersheds. Given the high costs of water treatment in densely populated regions, there is a pressing need to plan and manage landscapes in order to ensure adequate water resources. In tropical regions, maintaining or restoring native vegetation cover is a promising intervention to sustain adequate water quality.
Assuntos
Rios , Qualidade da Água , Brasil , Mudança Climática , Ecossistema , Monitoramento Ambiental , Florestas , HumanosRESUMO
The Caatinga biome covers an area of 844,453km(2) and has enormous endemic biodiversity, with unique characteristics that make it an exclusive Brazilian biome. It falls within the earth's tropical zone and is one of the several important ecoregions of Brazil. This biome undergoes natural lengthy periods of drought that cause losses in crop and livestock productivity, having a severe impact on the population. Due to the vulnerability of this ecosystem to climate change, livestock has emerged as the main livelihood of the rural population, being the precursor of the replacement of native vegetation by grazing areas. This study aimed to measure GHG emissions from two different soil covers: native forest (Caatinga) and pasture in the municipality of São João, Pernambuco State, in the years 2013 and 2014. GHG measurements were taken by using static chamber techniques in both soil covers. According to a previous search, so far, this is the first study measuring GHG emissions using the static chamber in the Caatinga biome. N2O emissions ranged from -1.0 to 4.2mgm(-2)d(-1) and -1.22 to 3.4mgm(-2)d(-1) in the pasture and Caatinga, respectively, and they did not significantly differ from each other. Emissions were significantly higher during dry seasons. Carbon dioxide ranged from -1.1 to 14.1 and 1.2 to 15.8gm(-2)d(-1) in the pasture and Caatinga, respectively. CO2 emissions were higher in the Caatinga in 2013, and they were significantly influenced by soil temperature, showing an inverse relation. Methane emission ranged from 6.6 to 6.8 and -6.0 to 4.8mgm(-2)d(-1) in the pasture and Caatinga, respectively, and was significantly higher only in the Caatinga in the rainy season of 2014. Soil gas fluxes seemed to be influenced by climatic and edaphic conditions as well as by soil cover in the Caatinga biome.