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Journal articles on the topic 'Vegetation changes'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

He, Dong, Xianglin Huang, Qingjiu Tian, and Zhichao Zhang. "Changes in Vegetation Growth Dynamics and Relations with Climate in Inner Mongolia under More Strict Multiple Pre-Processing (2000–2018)." Sustainability 12, no. 6 (March 24, 2020): 2534. http://dx.doi.org/10.3390/su12062534.

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Inner Mongolia Autonomous Region (IMAR) is related to China’s ecological security and the improvement of ecological environment; thus, the vegetation’s response to climate changes in IMAR has become an important part of current global change research. As existing achievements have certain deficiencies in data preprocessing, technical methods and research scales, we correct the incomplete data pre-processing and low verification accuracy; use grey relational analysis (GRA) to study the response of Enhanced Vegetation Index (EVI) in the growing season to climate factors on the pixel scale; explore the factors that affect the response speed and response degree from multiple perspectives, including vegetation type, longitude, latitude, elevation and local climate type; and solve the problems of excessive ignorance of details and severe distortion of response results due to using average values of the wide area or statistical data. The results show the following. 1. The vegetation status of IMAR in 2000-2018 was mainly improved. The change rates were 0.23/10° N and 0.25/10° E, respectively. 2. The response speed and response degree of forests to climatic factors are higher than that of grasslands. 3. The lag time of response for vegetation growth to precipitation, air temperature and relative humidity in IMAR is mainly within 2 months. The speed of vegetation‘s response to climate change in IMAR is mainly affected by four major factors: vegetation type, altitude gradient, local climate type and latitude. 4. Vegetation types and altitude gradients are the two most important factors affecting the degree of vegetation’s response to climate factors. It is worth noting that when the altitude rises to 2500 m, the dominant factor for the vegetation growth changes from precipitation to air temperature in terms of hydrothermal combination in the environment. Vegetation growth in areas with relatively high altitudes is more dependent on air temperature.

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2

Collinson, Margaret E. "Mass extinctions: Catastrophic vegetation changes." Nature 324, no. 6093 (November 1986): 112. http://dx.doi.org/10.1038/324112a0.

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3

Pancer-Koteja, Elżbieta, Jerzy Szwagrzyk, and Marcin Guzik. "Quantitative estimation of vegetation changes by comparing two vegetation maps." Plant Ecology 205, no. 1 (April 7, 2009): 139–54. http://dx.doi.org/10.1007/s11258-009-9604-5.

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4

Richards, Daniel R., and Richard N. Belcher. "Global Changes in Urban Vegetation Cover." Remote Sensing 12, no. 1 (December 19, 2019): 23. http://dx.doi.org/10.3390/rs12010023.

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Urban vegetation provides many ecosystem services that make cities more liveable for people. As the world continues to urbanise, the vegetation cover in urban areas is changing rapidly. Here we use Google Earth Engine to map vegetation cover in all urban areas larger than 15 km2 in 2000 and 2015, which covered 390,000 km2 and 490,000 km2 respectively. In 2015, urban vegetation covered a substantial area, equivalent to the size of Belarus. Proportional vegetation cover was highly variable, and declined in most urban areas between 2000 and 2015. Declines in proportional vegetated cover were particularly common in the Global South. Conversely, proportional vegetation cover increased in some urban areas in eastern North America and parts of Europe. Most urban areas that increased in vegetation cover also increased in size, suggesting that the observed net increases were driven by the capture of rural ecosystems through low-density suburban sprawl. Far fewer urban areas achieved increases in vegetation cover while remaining similar in size, although this trend occurred in some regions with shrinking populations or economies. Maintaining and expanding urban vegetation cover alongside future urbanisation will be critical for the well-being of the five billion people expected to live in urban areas by 2030.

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5

Nørnberg, P., L. Sloth, and K. E. Nielsen. "Rapid changes of sandy soils caused by vegetation changes." Canadian Journal of Soil Science 73, no. 4 (November 1, 1993): 459–68. http://dx.doi.org/10.4141/cjss93-047.

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Development of Typic Haplorthods in a heathland area in Denmark responded over a short period of time (decades) to changes of vegetation. Part of the heath, Hjelm Hede, was left undisturbed and was invaded by trees, mainly oak and a few aspen and conifers. Another part of the heath was planted with Norway and Sitka spruce 60–70 yr ago. The soils under heath, oak and spruce were studied. Major differences were found, some visible in the field and others detectable in the laboratory. Under oak, relative to heath, horizon boundaries were less distinct, pH increased in the top horizons, organic carbon and C/N ratio decreased, and iron and aluminum contents in the upper B horizons decreased. Compared with the original heath podzol, the soil under spruce had a lower pH in the O, E and upper B horizons, higher organic carbon content and C/N ratio in the top horizons, increased cementation, and a placic horizon. However the pyrophosphate-extractable iron and aluminum content was significantly lower than in any of the other soils. The soil under oak showed "depodzolization" features, whereas the soil under spruce was increasingly podzolized, though the podzolization mechanism might be different from that under heath. Analyses of phenolic compounds in the soil water were consistent with these conclusions. The three main components of substituted benzoic acids were gallic acid, protocatechuic acid and coumaric acid, which are all strongly complexing agents believed to take part in the podzolization process. Generally, the highest concentrations were found under spruce and the lowest under oak.Key words: Vegetation-induced soil changes, Spodosols, phenolic compounds

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6

Whitlock, Cathy. "Postglacial Fire Frequency and its Relation to Long-Term Vegetational and Climatic Changes in Yellowstone Park." UW National Parks Service Research Station Annual Reports 16 (January 1, 1992): 212–18. http://dx.doi.org/10.13001/uwnpsrc.1992.3123.

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The primary research objective has been to study the vegetational history of Yellowstone and its sensitivity to changes in climate and fire frequency. To establish a sequence of vegetational changes, a network of pollen records spanning the last 14,000 years has been studied from different types of vegetation within the Park. The relationship between modern pollen rain, modern vegetation and presentÂday climate in the northern Rocky Mountains has been the basis for interpreting past vegetation and climate from the fossil records. Changes in fire regime during the past 14,000 years have been inferred from sedimentary charcoal and other fire proxy in lake sediments. Calibration of the fire signal is based on a study that measures the input of charcoal into lakes following the 1988 fires in Yellowstone.

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7

Wang, Weiming, Chunhai Li, Junwu Shu, and Wei Chen. "Changes of vegetation in southern China." Science China Earth Sciences 62, no. 8 (May 31, 2019): 1316–28. http://dx.doi.org/10.1007/s11430-018-9364-9.

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8

Cho, Mee-Hyun, Ah-Ryeon Yang, Eun-Hyuk Baek, Sarah M. Kang, Su-Jong Jeong, Jin Young Kim, and Baek-Min Kim. "Vegetation-cloud feedbacks to future vegetation changes in the Arctic regions." Climate Dynamics 50, no. 9-10 (July 31, 2017): 3745–55. http://dx.doi.org/10.1007/s00382-017-3840-5.

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9

Solon, Jerzy. "Changes in the vegetation landscape in the Pińczów environs (S Poland)." Phytocoenologia 21, no. 4 (April 19, 1993): 387–409. http://dx.doi.org/10.1127/phyto/21/1993/387.

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10

Zhao, Fangfang, Zongxue Xu, and Lu Zhang. "Changes in streamflow regime following vegetation changes from paired catchments." Hydrological Processes 26, no. 10 (September 28, 2011): 1561–73. http://dx.doi.org/10.1002/hyp.8266.

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11

Volpers, Th. "Changes in microclimate and vegetation after thinning in a montane virgin forest." Phytocoenologia 17, no. 1 (February 6, 1989): 71–104. http://dx.doi.org/10.1127/phyto/17/1989/71.

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12

Gomez, F., E. Gaja, and A. Reig. "Vegetation and climatic changes in a city." Ecological Engineering 10, no. 4 (July 1998): 355–60. http://dx.doi.org/10.1016/s0925-8574(98)00002-0.

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13

Fox, Barry J., Jennifer E. Taylor, Marilyn D. Fox, and Carole Williams. "Vegetation changes across edges of rainforest remnants." Biological Conservation 82, no. 1 (October 1997): 1–13. http://dx.doi.org/10.1016/s0006-3207(97)00011-6.

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14

Alward, R. D. "Grassland Vegetation Changes and Nocturnal Global Warming." Science 283, no. 5399 (January 8, 1999): 229–31. http://dx.doi.org/10.1126/science.283.5399.229.

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15

Turcotte, Kevin M., Kamlesh Lulla, and Gopalan Venugopal. "Mapping small‐scale vegetation changes of Mexico." Geocarto International 8, no. 4 (December 1993): 73–85. http://dx.doi.org/10.1080/10106049309354431.

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16

Olech, Maria, Michał Węgrzyn, Maja Lisowska, Agnieszka Słaby, and Piotr Angiel. "Contemporary Changes in Vegetation of Polar Regions." Papers on Global Change IGBP 18, no. 1 (January 1, 2011): 35–51. http://dx.doi.org/10.2478/v10190-010-0003-8.

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Contemporary Changes in Vegetation of Polar Regions Rapid climate changes which have been observed over the recent years in both polar regions of the Earth, directly or indirectly affect vegetation dynamics. This article presents the main directions of the changes taking place in the recent years in tundra communities of both polar regions, based on original research carried out in the Arctic in Spitsbergen and in the maritime Antarctic on King George Island.

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17

HENDERSON-SELLERS, A., and K. McGUFFIE. "Global climate models and 'dynamic' vegetation changes." Global Change Biology 1, no. 1 (February 1995): 63–75. http://dx.doi.org/10.1111/j.1365-2486.1995.tb00007.x.

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18

Graf, Ulrich, Otto Wildi, Meinrad Küchler, and Klaus Ecker. "Five-year changes in Swiss mire vegetation." Botanica Helvetica 120, no. 1 (June 18, 2010): 15–27. http://dx.doi.org/10.1007/s00035-010-0071-3.

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19

Xu, Nianxu, Jia Tian, Qingjiu Tian, Kaijian Xu, and Shaofei Tang. "Analysis of Vegetation Red Edge with Different Illuminated/Shaded Canopy Proportions and to Construct Normalized Difference Canopy Shadow Index." Remote Sensing 11, no. 10 (May 19, 2019): 1192. http://dx.doi.org/10.3390/rs11101192.

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Shadows exist universally in sunlight-source remotely sensed images, and can interfere with the spectral morphological features of green vegetations, resulting in imprecise mathematical algorithms for vegetation monitoring and physiological diagnoses; therefore, research on shadows resulting from forest canopy internal composition is very important. Red edge is an ideal indicator for green vegetation’s photosynthesis and biomass because of its strong connection with physicochemical parameters. In this study, red edge parameters (curve slope and reflectance) and the normalized difference vegetation index (NDVI) of two species of coniferous trees in Inner Mongolia, China, were studied using an unmanned aerial vehicle’s hyperspectral visible-to-near-infrared images. Positive correlations between vegetation red edge slope and reflectance with different illuminated/shaded canopy proportions were obtained, with all R2s beyond 0.850 (p < 0.01). NDVI values performed steadily under changes of canopy shadow proportions. Therefore, we devised a new vegetation index named normalized difference canopy shadow index (NDCSI) using red edge’s reflectance and the NDVI. Positive correlations (R2 = 0.886, p < 0.01) between measured brightness values and NDCSI of validation samples indicated that NDCSI could differentiate illumination/shadow circumstances of a vegetation canopy quantitatively. Combined with the bare soil index (BSI), NDCSI was applied for linear spectral mixture analysis (LSMA) using Sentinel-2 multispectral imaging. Positive correlations (R2 = 0.827, p < 0.01) between measured brightness values and fractional illuminated vegetation cover (FIVC) demonstrate the capacity of NDCSI to accurately calculate the fractional cover of illuminated/shaded vegetation, which can be utilized to calculate and extract the illuminated vegetation canopy from satellite images.

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20

Groppo, J. D., S. R. M. Lins, P. B. Camargo, E. D. Assad, H. S. Pinto, S. C. Martins, P. R. Salgado, et al. "Changes in soil carbon, nitrogen, and phosphorus due to land-use changes in Brazil." Biogeosciences 12, no. 15 (August 7, 2015): 4765–80. http://dx.doi.org/10.5194/bg-12-4765-2015.

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Abstract. In this paper, soil carbon, nitrogen and phosphorus concentrations and stocks were investigated in agricultural and natural areas in 17 plot-level paired sites and in a regional survey encompassing more than 100 pasture soils In the paired sites, elemental soil concentrations and stocks were determined in native vegetation (forests and savannas), pastures and crop–livestock systems (CPSs). Nutrient stocks were calculated for the soil depth intervals 0–10, 0–30, and 0–60 cm for the paired sites and 0–10, and 0–30 cm for the pasture regional survey by sum stocks obtained in each sampling intervals (0–5, 5–10, 10–20, 20–30, 30–40, 40–60 cm). Overall, there were significant differences in soil element concentrations and ratios between different land uses, especially in the surface soil layers. Carbon and nitrogen contents were lower, while phosphorus contents were higher in the pasture and CPS soils than in native vegetation soils. Additionally, soil stoichiometry has changed with changes in land use. The soil C : N ratio was lower in the native vegetation than in the pasture and CPS soils, and the carbon and nitrogen to available phosphorus ratio (PME) decreased from the native vegetation to the pasture to the CPS soils. In the plot-level paired sites, the soil nitrogen stocks were lower in all depth intervals in pasture and in the CPS soils when compared with the native vegetation soils. On the other hand, the soil phosphorus stocks were higher in all depth intervals in agricultural soils when compared with the native vegetation soils. For the regional pasture survey, soil nitrogen and phosphorus stocks were lower in all soil intervals in pasture soils than in native vegetation soils. The nitrogen loss with cultivation observed here is in line with other studies and it seems to be a combination of decreasing organic matter inputs, in cases where crops replaced native forests, with an increase in soil organic matter decomposition that leads to a decrease in the long run. The main cause of the increase in soil phosphorus stocks in the CPS and pastures of the plot-level paired site seems to be linked to phosphorus fertilization by mineral and organics fertilizers. The findings of this paper illustrate that land-use changes that are currently common in Brazil alter soil concentrations, stocks and elemental ratios of carbon, nitrogen and phosphorus. These changes could have an impact on the subsequent vegetation, decreasing soil carbon and increasing nitrogen limitation but alleviating soil phosphorus deficiency.

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21

Zhang, H. Z., T. H. Chi, and J. R. Fan. "Modelling of the hydrological connectivity changes in the Minjiang Upstream after the Wenchuan earthquake using satellite remote sensing and DEM data." Natural Hazards and Earth System Sciences Discussions 3, no. 2 (February 5, 2015): 1113–36. http://dx.doi.org/10.5194/nhessd-3-1113-2015.

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Abstract. The 2008 Wenchuan earthquake-induced landslides destroyed larger areas of mountain vegetation and produced large volume of landslide-debris, which made the vegetation's hydrological adjusting function diminished and made the hydrological progresses in slopes changed, resulting in severe erosion and catastrophic debris flows for a rather long time. Since 2008, the landslide-damaged vegetation and its hydrological function have been recovering. In this paper, the Minjiang Upstream watersheds around Yingxiu Town were selected. First, the landslide-damaged vegetation was identified and monitored via multi-temporal (2001–2014) satellite images. Then, the slope materials stability was assessed through topographic analysis of the vegetation survival environments. Then, the hydrological connectivity index (HCI) was defined to describe the upstream sediment production and downstream transport pathway. Finally, results indicated that HCI decreased annually with the vegetation recovery after the obvious increases during the earthquakes. While, analysis of 2008–2013 debris flow events indicated that the areas, the vertical drop to river <1000 m and the horizontal distance to river <2500 m, have high HCI increases and are more susceptible for debris flow formation. Monitoring the landslide-damaged vegetation recovery processes can contribute to assess the hydrological connectivity changes and understand the debris flow formation.

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22

Yang, Chen, Meichen Fu, Dingrao Feng, Yiyu Sun, and Guohui Zhai. "Spatiotemporal Changes in Vegetation Cover and Its Influencing Factors in the Loess Plateau of China Based on the Geographically Weighted Regression Model." Forests 12, no. 6 (May 25, 2021): 673. http://dx.doi.org/10.3390/f12060673.

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Vegetation plays a key role in ecosystem regulation and influences our capacity for sustainable development. Global vegetation cover has changed dramatically over the past decades in response to both natural and anthropogenic factors; therefore, it is necessary to analyze the spatiotemporal changes in vegetation cover and its influencing factors. Moreover, ecological engineering projects, such as the “Grain for Green” project implemented in 1999, have been introduced to improve the ecological environment by enhancing forest coverage. In our study, we analyzed the changes in vegetation cover across the Loess Plateau of China and the impacts of influencing factors. First, we analyzed the latitudinal and longitudinal changes in vegetation coverage. Second, we displayed the spatiotemporal changes in vegetation cover based on Theil-Sen slope analysis and the Mann-Kendall test. Third, the Hurst exponent was used to predict future changes in vegetation coverage. Fourth, we assessed the relationship between vegetation cover and the influence of individual factors. Finally, ordinary least squares regression and the geographically weighted regression model were used to investigate the influence of various factors on vegetation cover. We found that the Loess Plateau showed large-scale greening from 2000 to 2015, though some regions showed decreasing vegetation cover. Latitudinal and longitudinal changes in vegetation coverage presented a net increase. Moreover, some areas of the Loess Plateau are at risk of degradation in the future, but most areas showed a sustainable increase in vegetation cover. Temperature, precipitation, gross domestic product (GDP), slope, cropland percentage, forest percentage, and built-up land percentage displayed different relationships with vegetation cover. Geographically weighted regression model revealed that GDP, temperature, precipitation, forest percentage, cropland percentage, built-up land percentage, and slope significantly influenced (p < 0.05) vegetation cover in 2000. In comparison, precipitation, forest percentage, cropland percentage, and built-up land percentage significantly affected (p < 0.05) vegetation cover in 2015. Our results enhance our understanding of the ecological and environmental changes in the Loess Plateau.

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23

Prieto, Aldo Raúl. "Late Quaternary Vegetational and Climatic Changes in the Pampa Grassland of Argentina." Quaternary Research 45, no. 1 (January 1996): 73–88. http://dx.doi.org/10.1006/qres.1996.0007.

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AbstractThe vegetation and climate of the Pampa grassland, Argentina, during the late Quaternary are reconstructed from pollen recovered from dated stratigraphic sections from arroyo walls and from archaelogical excavations. Prior to 10,500 yr B.P., herbaceous psammophytic steppe existed in the central part of the Pampa grassland while xerophytic woodland associated with psammophytic and halophytic steppe occurred in the southwestern part of the Pampa. These types of vegetation and the continental conditions that prevailed in the area of the present-day coast (38°S), indicate subhumid-dry climate and annual precipitation 100 mm lower than present. A subsequent change toward a vegetation characteristic of ponds, swamps, and foodplains, or toward environments with locally more effective moisture, occurred ca. 10,500 yr B.P. suggesting annual precipitation close to modern levels or a higher availability of water in the central part of the Pampa grassland, this type of vegetation existed until 8000 yr B.P., when it was replaced by grassland communities that lasted until 7000 yr B.P. In the southwestern part of the Pampa grassland, this vegetation developed before 7000 yr B.P. and persisted until ca. 5000 yr B.P. Sea level higher than the present ca. 6200 yr B.P. is consistent with sharp modification of the vegetation and development of local halophytic communities dominant at 38°S. A return to subhumid-dry conditions occurred after 5000 yr B.P. The late Holocene vegetation is characterized by pollen assemblages similar to the psammophytic and halophytic communities of the Southern pampa grassland, associated with communities with more edaphic conditions. At the same time, at 38°S a sea level regression is suggested by the dominance of fresh-water pollen assemblages and micropaleontological remains. The trend toward humid, temperate conditions ca. 1000 yr B.P. suggested by vertebrate remains characteristic of temperate and humid conditions, as well as a very short but dry episode during the 18th century suggested by the geology, are not clearly evidenced in the pollen sequences. Vegetational and climatic changes are explained by the latitudinal shifts and changes in intensity of the southern atmospheric circulation and changes in sea level.

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24

Potter, Christopher, and Olivia Alexander. "Changes in Vegetation Phenology and Productivity in Alaska Over the Past Two Decades." Remote Sensing 12, no. 10 (May 13, 2020): 1546. http://dx.doi.org/10.3390/rs12101546.

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Understanding trends in vegetation phenology and growing season productivity at a regional scale is important for global change studies, particularly as linkages can be made between climate shifts and the vegetation’s potential to sequester or release carbon into the atmosphere. Trends and geographic patterns of change in vegetation growth and phenology from the MODerate resolution Imaging Spectroradiometer (MODIS) satellite data sets were analyzed for the state of Alaska over the period 2000 to 2018. Phenology metrics derived from the MODIS Normalized Difference Vegetation Index (NDVI) time-series at 250 m resolution tracked changes in the total integrated greenness cover (TIN), maximum annual NDVI (MAXN), and start of the season timing (SOST) date over the past two decades. SOST trends showed significantly earlier seasonal vegetation greening (at more than one day per year) across the northeastern Brooks Range Mountains, on the Yukon-Kuskokwim coastal plain, and in the southern coastal areas of Alaska. TIN and MAXN have increased significantly across the western Arctic Coastal Plain and within the perimeters of most large wildfires of the Interior boreal region that burned since the year 2000, whereas TIN and MAXN have decreased notably in watersheds of Bristol Bay and in the Cook Inlet lowlands of southwestern Alaska, in the same regions where earlier-trending SOST was also detected. Mapping results from this MODIS time-series analysis have identified a new database of localized study locations across Alaska where vegetation phenology has recently shifted notably, and where land cover types and ecosystem processes could be changing rapidly.

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25

LI, Yunqing, Kazuhiko OHNUMA, and Yoshizumi YASUDA. "Analysis of Chinese vegetation properties by time series changes of global vegetation index." Journal of the Japan society of photogrammetry and remote sensing 29, no. 1 (1990): 4–12. http://dx.doi.org/10.4287/jsprs.29.4.

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26

Wan, Lei, Huiyu Liu, Haibo Gong, and Yujia Ren. "Effects of Climate and Land Use changes on Vegetation Dynamics in the Yangtze River Delta, China Based on Abrupt Change Analysis." Sustainability 12, no. 5 (March 4, 2020): 1955. http://dx.doi.org/10.3390/su12051955.

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Vegetation dynamics is thought to be affected by climate and land use changes. However, how the effects vary after abrupt vegetation changes remains unclear. Based on the Mann-Kendall trend and abrupt change analysis, we monitored vegetation dynamics and its abrupt change in the Yangtze River delta during 1982–2016. With the correlation analysis, we revealed the relationship of vegetation dynamics with climate changes (temperature and precipitation) pixel-by-pixel and then with land use changes analysis we studied the effects of land use changes (unchanged or changed land use) on their relationship. Results showed that: (1) the Normalized Vegetation Index (NDVI) during growing season that is represented as GSN (growing season NDVI) showed an overall increasing trend and had an abrupt change in 2000. After then, the area percentages with decreasing GSN trend increased in cropland and built-up land, mainly located in the eastern, while those with increasing GSN trend increased in woodland and grassland, mainly located in the southern. Changed land use, except the land conversions from/to built-up land, is more favor for vegetation greening than unchanged land use (2) after abrupt change, the significant positive correlation between precipitation and GSN increased in all unchanged land use types, especially for woodland and grassland (natural land use) and changed land use except built-up land conversion. Meanwhile, the insignificant positive correlation between temperature and GSN increased in woodland, while decreased in the cropland and built-up land in the northwest (3) after abrupt change, precipitation became more important and favor, especially for natural land use. However, temperature became less important and favor for all land use types, especially for built-up land. This research indicates that abrupt change analysis will help to effectively monitor vegetation trend and to accurately assess the relationship of vegetation dynamics with climate and land use changes.

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27

Myhre, Gunnar, and Arne Myhre. "Uncertainties in Radiative Forcing due to Surface Albedo Changes Caused by Land-Use Changes." Journal of Climate 16, no. 10 (May 15, 2003): 1511–24. http://dx.doi.org/10.1175/1520-0442-16.10.1511.

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Abstract A radiative transfer model has been used for estimating the radiative forcing due to land-use changes. Five global datasets for current vegetation cover and three datasets of preagriculture vegetation have been adopted. The vegetation datasets have been combined with three datasets for surface albedo values. A distinct feature in all the calculations is the negative radiative forcing at the northern midlatitudes due to the conversion of forest to cropland. Regionally the radiative forcing is likely to be among the strongest of the climate forcing mechanisms. A wider range is estimated for the global mean radiative forcing due to land-use changes than previously reported. The single most important factor yielding the large range in estimated forcing is the cropland surface albedo values. This underlines the importance of characterizing surface albedo correctly.

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28

Timalsina, Bhuban, Suzanne Mavoa, and Amy K. Hahs. "Dynamic Changes in Melbourne’s Urban Vegetation Cover—2001 to 2016." Land 10, no. 8 (August 2, 2021): 814. http://dx.doi.org/10.3390/land10080814.

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Understanding changes in urban vegetation is essential for ensuring sustainable and healthy cities, mitigating disturbances due to climate change, sustaining urban biodiversity, and supporting human health and wellbeing. This study investigates and describes the distribution and dynamic changes in urban vegetation over a 15-year period in Greater Melbourne, Australia. The study investigates how vegetation cover across Melbourne has changed at five-yearly intervals from 2001 to 2016 using the newly proposed dynamic change approach that extends the net change approach to quantify the amount of vegetation gain as well as loss. We examine this question at two spatial resolutions: (1) at the municipal landscape scale to capture broadscale change regardless of land tenure; and (2) at the scale of designated public open spaces within the municipalities to investigate the extent to which the loss of vegetation has occurred on lands that are intended to provide public access to vegetated areas in the city. Vegetation was quantified at four different times (2001, 2006, 2011, 2016), using the normalized difference vegetation index (NDVI). Dynamic changes of gain and loss in urban vegetation between the three periods were quantified for six local government areas (LGAs) and their associated public open spaces using a change matrix. The results showed an overall net loss of 64.5 square kilometres of urban vegetation from 2001 to 2016 in six LGAs. When extrapolated to the Greater Melbourne Area, this is approximately equivalent to 109 times the size of Central Park in New York City.

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Barbosa, João Paulo Rodrigues Alves Delfino, Serge Rambal, Angela Maria Soares, Florent Mouillot, Joana Messias Pereira Nogueira, and Giordane Augusto Martins. "Plant physiological ecology and the global changes." Ciência e Agrotecnologia 36, no. 3 (June 2012): 253–69. http://dx.doi.org/10.1590/s1413-70542012000300001.

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The global changes are marked by alteration on the normal patterns of important biochemical and biophysical processes of the Earth. However, the real effects as well as the feedbacks of the global changes over vegetation are still unclear. Part of this uncertainty can be attributed to the inattention of stakeholders and scientists towards vegetation and its complex interrelations with the environment, which drive plant physiological processes in different space-time scales. Notwithstanding, some key subjects of the global changes could be better elucidated with a more plant physiological ecology approach. We discuss some issues related to this topic, going through some limitations of approaching vegetation as a static component of the biosphere as the other sub-systems of the Earth-system change. With this perspective, this review is an initial reflection towards the assessment of the role and place of vegetation structure and function in the global changes context. We reviewed the Earth-system and global changes terminology; attempted to illustrate key plant physiological ecology researches themes in the global changes context; consider approaching plants as complex systems in order to adequately quantify systems characteristics as sensibility, homeostasis, and vulnerability. Moreover, we propose insights that would allow vegetation studies and scaling procedures in the context of the Earth-system. We hope this review will assist researchers on their strategy to identify, understand and anticipate the potential effects of global changes over the most vulnerable vegetation processes from the leaf to the global levels.

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30

Groppo, J. D., S. R. M. Lins, P. B. Camargo, E. D. Assad, H. S. Pinto, S. C. Martins, P. R. Salgado, et al. "Changes in soil carbon, nitrogen and phosphorus due to land-use changes in Brazil." Biogeosciences Discussions 12, no. 3 (February 4, 2015): 2533–71. http://dx.doi.org/10.5194/bgd-12-2533-2015.

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Abstract. In this paper soil carbon, nitrogen and phosphorus concentrations and related elemental ratios, as well as and nitrogen and phosphorus stocks were investigated in 17 paired sites and in a regional survey encompassing more than 100 pasture soils in the Cerrado, Atlantic Forest, and Pampa, the three important biomes of Brazil. In the paired sites, elemental soil concentrations and stocks were determined in native vegetation, pastures and crop-livestock systems (CPS). Overall, there were significant differences in soil element concentrations and ratios between different land uses, especially in the surface soil layers. Carbon and nitrogen contents were lower, while phosphorus contents were higher in the pasture and CPS soils than in forest soils. Additionally, soil stoichiometry has changed with changes in land use. The soil C : N ratio was lower in the forest than in the pasture and CPS soils; and the carbon and nitrogen to available phosphorus ratio (PME) decreased from the forest to the pasture to the CPS soils. The average native vegetation soil nitrogen stocks at 0–10, 0–30 and 0–60 cm soil depth layers were equal to approximately 2.3, 5.2, 7.3 Mg ha−1, respectively. In the paired sites, nitrogen loss in the CPS systems and pasture soils were similar and equal to 0.6, 1.3 and 1.5 Mg ha−1 at 0–10, 0–30 and 0–60 cm soil depths, respectively. In the regional pasture soil survey, nitrogen soil stocks at 0–10 and 0–30 soil layers were equal to 1.6 and 3.9 Mg ha−1, respectively, and lower than the stocks found in the native vegetation of paired sites. On the other hand, the soil phosphorus stocks were higher in the CPS and pasture of the paired sites than in the soil of the original vegetation. The original vegetation soil phosphorus stocks were equal to 11, 22, and 43 kg ha−1 in the three soil depths, respectively. The soil phosphorus stocks increased in the CPS systems to 30, 50, and 63 kg ha−1, respectively, and in the pasture pair sites to 22, 47, and 68 kg ha−1, respectively. In the regional pasture survey, the soil phosphorus stocks were lower than in the native vegetation, and equal to 9 and 15 kg ha−1 at 0–10 and 0–30 depth layer. The findings of this paper illustrate that land-use changes that are currently common in Brazil alter soil concentrations, stocks and elemental ratios of carbon, nitrogen and phosphorus. These changes could have an impact on the subsequent vegetation, decreasing soil carbon, increasing nitrogen limitation, but alleviating soil phosphorus deficiency.

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Dyderski, Marcin K., and Andrzej M. Jagodziński. "Changes in vegetation of the Mszar Bogdaniec nature reserve." Forest Research Papers 77, no. 2 (June 1, 2016): 104–16. http://dx.doi.org/10.1515/frp-2016-0012.

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Abstract Changes of vegetation in forests and wetlands require continuous monitoring and evaluation. Due to the lack of in-depth knowledge, it is still very challenging to predict and record vegetation changes. This study attempts to evaluate changes in forest and transitional bog vegetation over 14 years in the Mszar Bogdaniec nature reserve (West Poland; 21.98 ha). We described the current vegetation using 50 phytosociological relevés conducted in 2012 and 2013. Moreover, we calculated and compared ecological indices describing ecological traits of the vegetation in two different times. We also used Detrended Correspondence Analysis (DCA) to assess changes in floral composition. Most of the studied vegetation traits did not change significantly during the last 14 years. Statistically significant changes occured in the proportion of mosses and cover of the herb layer, both of which increased, as well as species richness in forest plant communities, and the cover of species from Scheuchzerio-Caricetea class in peat bog plant communities, both of which decreased. The current state of the vegetation is a result of former human activity such as drainage and planting monoculture tree stands. The observed changes during the last 14 years were fluctuations rather than direct changes. Encroachment of the woody species into transitional bog is a fluctuation, which may be secondary succession in the long-term.

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Jiang, Qinhua, and Dolores R. Piperno. "Environmental and Archaeological Implications of a Late Quaternary Palynological Sequence, Poyang Lake, Southern China." Quaternary Research 52, no. 2 (September 1999): 250–58. http://dx.doi.org/10.1006/qres.1999.2070.

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Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous–evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys.

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Khan, Roomana, Saleeha Asghar, and Vivek Kak. "699. A Retrospective Review of the Progression of Cardiac Vegetations with treatment." Open Forum Infectious Diseases 7, Supplement_1 (October 1, 2020): S401. http://dx.doi.org/10.1093/ofid/ofaa439.891.

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Abstract Background The purpose of our study was to assess the natural history of cardiac vegetations in native valves(NVIE) including changes in size and/or resolution with adequate treatment, as well as analyze factors that influence initial size. Methods We did a retrospective review of 102 patients discharged with a diagnosis NVIE at a community hospital. These patients were then screened to see if they received an adequate course of antimicrobial therapy and had follow up echocardiograms. The primary outcome measured was the change in vegetation size. We also assessed secondary measures including pathogen identified, the valve involved, complications, and associated IDU and any co-infections. Results 31 patients fulfilled the study criteria and showed an initial mean vegetation size of 170mm upon initial echocardiography. The follow-up size after antibiotic treatment was 78mm suggesting a statistically significant relationship between antibiotic completion and reduction in vegetation size. (p-value 0.005). T-Test was used for subgroup analysis and showed that the initial size of vegetations was significantly larger in IDUs (311) when compared to non-IDU (92)(p-value= 0.026).Patients who had embolic phenomena had significantly larger initial vegetations than those with no embolic complication. Initial vegetation size was significantly larger for people with embolic complications (308 mm vs 82.65 mm, p-value 0.013).We also found that patients with Staphylococcal endocarditis had larger vegetations than those with non-staphylococcal endocarditis (264 vs 39, p-value 0.001). and treatment led to a larger decrease in vegetation size (152 vs 7, p value 0.007) Conclusion Our small study suggests that successful treatment of NVIE does lead to a decrease in vegetation size though resolution of the vegetation does not occur. We also found that embolic phenomenon tended to occur with larger vegetations with our study suggesting that a vegetation > 3 cm was more likely to embolize. Our study also shows that vegetations in NVIE in injection drug users were larger than those in non-IDU and vegetation size is larger in patients with staphylococcal endocarditis however successful treatment in these patients also leads to a larger decrease in size of these vegetations Disclosures All Authors: No reported disclosures

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Strandberg, G., and E. Kjellström. "Climate Impacts from Afforestation and Deforestation in Europe." Earth Interactions 23, no. 1 (February 1, 2019): 1–27. http://dx.doi.org/10.1175/ei-d-17-0033.1.

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Abstract Changes in vegetation are known to have an impact on climate via biogeophysical effects such as changes in albedo and heat fluxes. Here, the effects of maximum afforestation and deforestation are studied over Europe. This is done by comparing three regional climate model simulations—one with present-day vegetation, one with maximum afforestation, and one with maximum deforestation. In general, afforestation leads to more evapotranspiration (ET), which leads to decreased near-surface temperature, whereas deforestation leads to less ET, which leads to increased temperature. There are exceptions, mainly in regions with little water available for ET. In such regions, changes in albedo are relatively more important for temperature. The simulated biogeophysical effect on seasonal mean temperature varies between 0.5° and 3°C across Europe. The effect on minimum and maximum temperature is larger than that on mean temperature. Increased (decreased) mean temperature is associated with an even larger increase (decrease) in maximum summer (minimum winter) temperature. The effect on precipitation is found to be small. Two additional simulations in which vegetation is changed in only one-half of the domain were also performed. These simulations show that the climatic effects from changed vegetation in Europe are local. The results imply that vegetation changes have had, and will have, a significant impact on local climate in Europe; the climatic response is comparable to climate change under RCP2.6. Therefore, effects from vegetation change should be taken into account when simulating past, present, and future climate for this region. The results also imply that vegetation changes could be used to mitigate local climate change.

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Tyler, Torbjörn, Stefan Andersson, Lars Fröberg, Kjell-Arne Olsson, Åke Svensson, and Ola Olsson. "Recent changes in the frequency of plant species and vegetation types in Scania, S Sweden, compared to changes during the twentieth century." Biodiversity and Conservation 29, no. 3 (November 26, 2019): 709–28. http://dx.doi.org/10.1007/s10531-019-01906-5.

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AbstractBased on data from three surveys of the vascular flora of the province of Scania, southernmost Sweden, conducted 1938–1971, 1987–2006 and 2008–2015, we analyse the change in frequency of individual species and groups of species associated with particular vegetation types. A majority of all species have experienced a change in frequency since 1938, and this turnover has continued in recent decades. The species showing the most dramatic declines since 1987 represent a mixture of arable weeds, grassland species and ruderals, but excludes forest species. In contrast, a majority of the most increasing species are escapes from cultivation that thrive under shaded conditions. The vegetation types showing the largest decreases since 1987 are all open seminatural grasslands and wetlands, while the vegetation types performing best are wooded. All vegetation types increasing since 1987 also increased during the 1900s; however, species of wooded types performed relatively better in recent decades, as opposed to the minimal increase observed for species of vegetation strongly influenced by human activities. Among decreasing vegetation types, those that have received much attention from conservationists, e.g. sand-steppe and calcareous fens tend to perform relatively better now than during the 1900s, while those that have received less attention, e.g. poor fens, oligotrophic waters and heaths, now comprise the most rapidly declining vegetation types. A majority of the species that decreased 1938–1996 also decreased 1987–2015, but, in general, species shown to have increased during the 1900s have not continued to increase.

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Han, Hongzhu, Jianjun Bai, Gao Ma, and Jianwu Yan. "Vegetation Phenological Changes in Multiple Landforms and Responses to Climate Change." ISPRS International Journal of Geo-Information 9, no. 2 (February 19, 2020): 111. http://dx.doi.org/10.3390/ijgi9020111.

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Vegetation phenology is highly sensitive to climate change, and the phenological responses of vegetation to climate factors vary over time and space. Research on the vegetation phenology in different climatic regimes will help clarify the key factors affecting vegetation changes. In this paper, based on a time-series reconstruction of Moderate-Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) data using the Savitzky–Golay filtering method, the phenology parameters of vegetation were extracted, and the Spatio-temporal changes from 2001 to 2016 were analyzed. Moreover, the response characteristics of the vegetation phenology to climate changes, such as changes in temperature, precipitation, and sunshine hours, were discussed. The results showed that the responses of vegetation phenology to climatic factors varied within different climatic regimes and that the Spatio-temporal responses were primarily controlled by the local climatic and topographic conditions. The following were the three key findings. (1) The start of the growing season (SOS) has a regular variation with the latitude, and that in the north is later than that in the south. (2) In arid areas in the north, the SOS is mainly affected by the temperature, and the end of the growing season (EOS) is affected by precipitation, while in humid areas in the south, the SOS is mainly affected by precipitation, and the EOS is affected by the temperature. (3) Human activities play an important role in vegetation phenology changes. These findings would help predict and evaluate the stability of different ecosystems.

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Økland, T. "Vegetational and ecological monitoring of boreal forests in Norway. I. Rausjømarka in Akershus county, SE Norway." Sommerfeltia 10, no. 1 (June 1, 1990): 1–56. http://dx.doi.org/10.2478/som-1990-0001.

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Abstract Vegetational and ecological monitoring of boreal forests in Norway was initiated in 1988, as a part of the programme “Countrywide monitoring of forest health” at Norwegian Institute of Land Invetory (NIJOS). Ten reference areas for monitoring will be established and analysed within five years; two new areas each year. Each of the monitoring areas is planned to be reanalysed every fifth year. In each monitoring area 10 macro sample plots, 50 m2 each, are selected. Within each macro sample plot 5 meso sample plots, 1 m2 each, are randomly placed and the vegetation is analysed by using frequency in subplots as measure of species abundance. Within each meso sample plot one micro sample plot (two in the first established monitoring area), 0.0625 m2 each, is analysed by the same method. In connection with each meso sample plot several environmental variables are recorded. In each ma cro sample plot several tree variables and variables describing the terrain are recorded. The variables are used for environmental interpretation as well as for monitoring, since known relations between vegetation and environmental gradients form the basis of vegetational and ecological monitoring. Any future changes in vegetation, soil and the health of trees have to be interpreted in relation to the analysis of vegetation-environment relationships in order to identify changes due to air pollution or climatic changes. The data from the first established monitoring area, Rausj0marka in Akershus county, are subjected to analysis in this paper. The most important vegetational and environmental gradients in the area are discussed, as well as the field methodology and the methods for data analysis to be used in integrated monitoring. The advantages of integrated monitoring of vegetation, soil and trees on the same sample plots are emphasized, including advantages for surveying and monitoring of species (bioindicators).

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Filipponi, Federico, Emiliana Valentini, Alessandra Nguyen Xuan, Carlos Guerra, Florian Wolf, Martin Andrzejak, and Andrea Taramelli. "Global MODIS Fraction of Green Vegetation Cover for Monitoring Abrupt and Gradual Vegetation Changes." Remote Sensing 10, no. 4 (April 23, 2018): 653. http://dx.doi.org/10.3390/rs10040653.

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Rokni, Komeil, and Tajul Ariffin Musa. "Normalized difference vegetation change index: A technique for detecting vegetation changes using Landsat imagery." CATENA 178 (July 2019): 59–63. http://dx.doi.org/10.1016/j.catena.2019.03.007.

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AN, Jin-Woo, Se-Hun KIM, Se-Kyu SONG, Un-Haing CHO, and In-Taek KIM. "The Changes of Vegetation of Daesongdo and Sosongdo." Korean Journal of Nature Conservation 9, no. 3_4 (December 2011): 211–26. http://dx.doi.org/10.30960/kjnc.2011.9.3_4.211.

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Duma, M., I. Alsina, and L. Dubova. "Changes of chemical composition of rhubarb during vegetation." Acta Horticulturae, no. 1142 (October 2016): 253–60. http://dx.doi.org/10.17660/actahortic.2016.1142.39.

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Morton, Howard L., and Alicia Melgoza. "Vegetation Changes following Brush Control in Creosotebush Communities." Journal of Range Management 44, no. 2 (March 1991): 133. http://dx.doi.org/10.2307/4002311.

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Peng, C. H., J. Guiot, and E. Van Campo. "Estimating changes in terrestrial vegetation and carbon storage." Quaternary Science Reviews 17, no. 8 (August 1998): 719–35. http://dx.doi.org/10.1016/s0277-3791(97)00045-0.

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Loeb, Robert E. "Measurement of Vegetation Changes Through Time by Resampling." Bulletin of the Torrey Botanical Club 117, no. 2 (April 1990): 173. http://dx.doi.org/10.2307/2997057.

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Overpeck, Jonathan T., David Rind, and Richard Goldberg. "Climate-induced changes in forest disturbance and vegetation." Nature 343, no. 6253 (January 1990): 51–53. http://dx.doi.org/10.1038/343051a0.

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Kim, Yoonmi, Kwang Hee Choi, and Pil Mo Jung. "Changes in foredune vegetation caused by coastal forests." Ocean & Coastal Management 102 (December 2014): 103–13. http://dx.doi.org/10.1016/j.ocecoaman.2014.09.001.

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Epstein, Howard E., Jed O. Kaplan, Heike Lischke, and Qin Yu. "Simulating Future Changes in Arctic and Subarctic Vegetation." Computing in Science & Engineering 9, no. 4 (July 2007): 12–23. http://dx.doi.org/10.1109/mcse.2007.84.

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Salvati, Luca, and Carlotta Ferrara. "Do changes in vegetation quality precede urban sprawl?" Area 45, no. 3 (August 15, 2013): 365–75. http://dx.doi.org/10.1111/area.12047.

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Phompila, Chittana, Megan Lewis, Kenneth Clarke, and Bertram Ostendorf. "Monitoring temporal Vegetation changes in Lao tropical forests." IOP Conference Series: Earth and Environmental Science 20 (June 23, 2014): 012054. http://dx.doi.org/10.1088/1755-1315/20/1/012054.

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Tasser, Erich, and Ulrike Tappeiner. "Impact of land use changes on mountain vegetation." Applied Vegetation Science 5, no. 2 (February 24, 2002): 173–84. http://dx.doi.org/10.1111/j.1654-109x.2002.tb00547.x.

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