Satellite‐derived NDVI underestimates the advancement of alpine vegetation growth over the past three decades

Features of reservoirs use make it necessary to collect, analyse and synthesise environmental information about the state of hydroecosystems with a purpose of their development forecast. Overgrowing processes are an important indicator of ecosystem. The following paper contains the results of the study of Chernovskoe reservoir flora and vegetation in different years. Floristic diversity is compared with other reservoirs and hydro botanic information about them has already been published in a number of the authors papers. The comparative analysis has shown that the overall composition of reservoirs flora is random, while there is some regularity in the environmental spectrum - each of them is characterized by a small number of aquatic species and by the dominance of coastal plant species. The study of Chernovskoe reservoir vegetation has shown that the composition of dominants has changed over the past 40 years, from 1974 to 2015. There is a dominance of air water vegetation above the water one, but the borders of the water vegetation growth have widened. Chernovskoe reservoir is currently in dynamic equilibrium. The lifetime of aquatic ecosystem at this stage may be unlimited if there is an unstable hydro regime and impulsive character of water use. The reservoir water level lowering may lead to overgrowth and accelerate activation of waterlogging.

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Changes in Vegetation Phenology and Productivity in Alaska Over the Past Two Decades

Remote Sensing ◽

10.3390/rs12101546 ◽

2020 ◽

Vol 12 (10) ◽

pp. 1546 ◽

Cited By ~ 1

Author(s):

Christopher Potter ◽

Olivia Alexander

Keyword(s):

Time Series ◽

Coastal Plain ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Regional Scale ◽

Data Sets ◽

Vegetation Phenology ◽

Vegetation Growth ◽

The Past ◽

Moderate Resolution Imaging Spectroradiometer

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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Forestland change and soil erosion in karst watershed under the Grain to Green Project

10.5194/egusphere-egu2020-4456 ◽

2020 ◽

Author(s):

Siwen Feng ◽

Hongya Wang ◽

Hongyan Liu ◽

Chenyi Zhu ◽

Shuai Li

Keyword(s):

Soil Erosion ◽

Influencing Factors ◽

Southwest China ◽

Drainage Basin ◽

Karst Area ◽

Karst Region ◽

Vegetation Growth ◽

The Past ◽

Pixel Scale ◽

River Drainage Basin

<div>With the implementation of the Grain to Green Project, the vegetation growth in karst region in southwest China has increased. In order to explore whether the growth of trees can be sustained after artificial afforestation in karst area and the influence of the forestland change on soil erosion, the WaTEM/SEDEM model was used to simulate the 11 stages of annual soil erosion in the past 33 years in Chongan river drainage basin in Guizhou, and the dominant influencing factors of soil erosion change in the past 33 years were discussed based the pixel scale in this study. The results showed that the forestland increased in a fluctuating way after the conversion project, and the decrease of forestland was mainly caused by drought, especially in the area where the dolomites were distributed. Therefore, the change of forestland caused no significant improvement in soil erosion since the Grain to Green Project.</div><p></p>

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Impacts of climate and CO2 changes on the vegetation growth and carbon balance of Qinghai–Tibetan grasslands over the past five decades

Global and Planetary Change ◽

10.1016/j.gloplacha.2012.08.009 ◽

2012 ◽

Vol 98-99 ◽

pp. 73-80 ◽

Cited By ~ 130

Author(s):

Shilong Piao ◽

Kun Tan ◽

Huijuan Nan ◽

Philippe Ciais ◽

Jingyun Fang ◽

...

Keyword(s):

Carbon Balance ◽

Vegetation Growth ◽

The Past

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Climatic history of the northeastern United States during the past 3000 years

10.5194/cp-2016-104 ◽

2016 ◽

Author(s):

Jennifer R. Marlon ◽

Neil Pederson ◽

Connor Nolan ◽

Simon Goring ◽

Bryan Shuman ◽

...

Keyword(s):

Warming Trend ◽

Ecosystem Dynamics ◽

Ice Age ◽

Extreme Weather Events ◽

Past Century ◽

Climate Conditions ◽

Vegetation Growth ◽

The Past ◽

Tree Ring Data ◽

Cooling Trend

Abstract. Many ecosystem processes that influence Earth system feedbacks, including vegetation growth, water and nutrient cycling, and disturbance regimes, are strongly influenced by multi-decadal to millennial-scale variations in climate that cannot be captured by instrumental climate observations. Paleoclimate information is therefore essential for understanding contemporary ecosystems and their potential trajectories under a variety of future climate conditions. With the exception of fossil pollen records, there are a limited number of northeastern US (NE US) paleoclimate archives that can provide constraints on its temperature and hydroclimate history. Moreover, the records that do exist have not been considered together. Tree-ring data indicate that the 20th century was one of the wettest of the past 500 years in the eastern US (Pederson et al., 2014), and lake-level records suggest it was one of the wettest in the Holocene (Newby et al., 2014); how such results compare with other available data remains unclear, however. Here we conduct a systematic review, assessment, and comparison of paleotemperature and paleohydrological proxies from the NE US for the last 3000 years. Regional temperature reconstructions are consistent with the long-term cooling trend (1000 BCE–1700 CE) evident in hemispheric-scale reconstructions, but hydroclimate reconstructions reveal new information, including an abrupt transition from wet to dry conditions around 550–750 CE. NE US paleo data suggest that conditions during the Medieval Climate Anomaly were warmer and drier than during the Little Ice Age, and drier than today. There is some evidence for an acceleration over the past century of a longer-term wetting trend in the NE US, and coupled with the abrupt shift from a cooling trend to a warming trend from increased greenhouse gases, may have wide-ranging implications for species distributions, ecosystem dynamics, and extreme weather events. More work is needed to gather paleoclimate data in the NE US, make inter-proxy comparisons, and improve estimates of uncertainty in the reconstructions.

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Climatic history of the northeastern United States during the past 3000 years

Climate of the Past ◽

10.5194/cp-13-1355-2017 ◽

2017 ◽

Vol 13 (10) ◽

pp. 1355-1379 ◽

Cited By ~ 18

Author(s):

Jennifer R. Marlon ◽

Neil Pederson ◽

Connor Nolan ◽

Simon Goring ◽

Bryan Shuman ◽

...

Keyword(s):

Ecosystem Dynamics ◽

Ice Age ◽

Extreme Weather Events ◽

Past Century ◽

Vegetation Growth ◽

The Past ◽

Weather Events ◽

Dry Conditions ◽

History Of ◽

Paleoclimate Records

Abstract. Many ecosystem processes that influence Earth system feedbacks – vegetation growth, water and nutrient cycling, disturbance regimes – are strongly influenced by multidecadal- to millennial-scale climate variations that cannot be directly observed. Paleoclimate records provide information about these variations, forming the basis of our understanding and modeling of them. Fossil pollen records are abundant in the NE US, but cannot simultaneously provide information about paleoclimate and past vegetation in a modeling context because this leads to circular logic. If pollen data are used to constrain past vegetation changes, then the remaining paleoclimate archives in the northeastern US (NE US) are quite limited. Nonetheless, a growing number of diverse reconstructions have been developed but have not yet been examined together. Here we conduct a systematic review, assessment, and comparison of paleotemperature and paleohydrological proxies from the NE US for the last 3000 years. Regional temperature reconstructions (primarily summer) show a long-term cooling trend (1000 BCE–1700 CE) consistent with hemispheric-scale reconstructions, while hydroclimate data show gradually wetter conditions through the present day. Multiple proxies suggest that a prolonged, widespread drought occurred between 550 and 750 CE. Dry conditions are also evident during the Medieval Climate Anomaly, which was warmer and drier than the Little Ice Age and drier than today. There is some evidence for an acceleration of the longer-term wetting trend in the NE US during the past century; coupled with an abrupt shift from decreasing to increasing temperatures in the past century, these changes could have wide-ranging implications for species distributions, ecosystem dynamics, and extreme weather events. More work is needed to gather paleoclimate data in the NE US to make inter-proxy comparisons and to improve estimates of uncertainty in reconstructions.

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The Impact Analysis of Subsidence on Vegetation Growth in Songzao Mining

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.805 ◽

2013 ◽

Vol 448-453 ◽

pp. 805-809

Author(s):

Gang Gu ◽

Ai Guo Wang ◽

Chen Cheng Hu ◽

Hai Chao Liang

Keyword(s):

Vegetation Index ◽

Impact Analysis ◽

Remote Sensing Data ◽

Self Healing ◽

Vegetation Growth ◽

The Past ◽

Grassland Ecosystems ◽

Wide Range ◽

Index Changes ◽

The Impact

In this paper, to gradually comprehensive analyze the impact of coal exploration to vegetation growth, Chongqing Songzao Mining was selected as the study area, vegetation index changes of the past decade were analyzed from a macro perspective using three remote sensing data, and then species composition and community structure of different times collapse area was analyzed using microscopic samples investigate. This paper argues that Songzao Mining exploitation of coal resources affected the local forest and grassland vegetation, but not on a wide range of forest and grassland ecosystems adversely affected, the area of forest and grassland ecosystems can carry local failure, and through the self-healing approach ultimately make forest grass ecosystem to stabilize.

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