Estimating fractional cover of photosynthetic vegetation, non-photosynthetic vegetation and bare soil in the Australian tropical savanna region upscaling the EO-1 Hyperion and MODIS sensors

2009 ◽  
Vol 113 (5) ◽  
pp. 928-945 ◽  
Author(s):  
Juan Pablo Guerschman ◽  
Michael J. Hill ◽  
Luigi J. Renzullo ◽  
Damian J. Barrett ◽  
Alan S. Marks ◽  
...  
Keyword(s):  
Bare Soil ◽  
Tropical Savanna ◽  
Fractional Cover

scholarly journals The MODIS Global Vegetation Fractional Cover Product 2001–2018: Characteristics of Vegetation Fractional Cover in Grasslands and Savanna Woodlands

2020 ◽  
Vol 12 (3) ◽  
pp. 406 ◽  
Author(s):  
Michael J. Hill ◽  
Juan P. Guerschman
Keyword(s):  
Land Use ◽  
Production Systems ◽  
Land Use Changes ◽  
Bare Soil ◽  
Additional Information ◽  
Fractional Cover ◽  
Grassland Type ◽  
Global Vegetation ◽  
Global Indicator

Vegetation Fractional Cover (VFC) is an important global indicator of land cover change, land use practice and landscape, and ecosystem function. In this study, we present the Global Vegetation Fractional Cover Product (GVFCP) and explore the levels and trends in VFC across World Grassland Type (WGT) Ecoregions considering variation associated with Global Livestock Production Systems (GLPS). Long-term average levels and trends in fractional cover of photosynthetic vegetation (FPV), non-photosynthetic vegetation (FNPV), and bare soil (FBS) are mapped, and variation among GLPS types within WGT Divisions and Ecoregions is explored. Analysis also focused on the savanna-woodland WGT Formations. Many WGT Divisions showed wide variation in long-term average VFC and trends in VFC across GLPS types. Results showed large areas of many ecoregions experiencing significant positive and negative trends in VFC. East Africa, Patagonia, and the Mitchell Grasslands of Australia exhibited large areas of negative trends in FNPV and positive trends FBS. These trends may reflect interactions between extended drought, heavy livestock utilization, expanded agriculture, and other land use changes. Compared to previous studies, explicit measurement of FNPV revealed interesting additional information about vegetation cover and trends in many ecoregions. The Australian and Global products are available via the GEOGLAM RAPP (Group on Earth Observations Global Agricultural Monitoring Rangeland and Pasture Productivity) website, and the scientific community is encouraged to utilize the data and contribute to improved validation.

scholarly journals Comparison of Hyperspectral Versus Traditional Field Measurements of Fractional Ground Cover in the Australian Arid Zone

2019 ◽  
Vol 11 (23) ◽  
pp. 2825 ◽  
Author(s):  
Claire Fisk ◽  
Kenneth Clarke ◽  
Megan Lewis
Keyword(s):  
Spatial Scale ◽  
Arid Zone ◽  
Ground Cover ◽  
Field Measurements ◽  
Bare Soil ◽  
Point Sampling ◽  
Calibration And Validation ◽  
Fractional Cover ◽  
In Situ Methods

The collection of high-quality field measurements of ground cover is critical for calibration and validation of fractional ground cover maps derived from satellite imagery. Field-based hyperspectral ground cover sampling is a potential alternative to traditional in situ techniques. This study aimed to develop an effective sampling design for spectral ground cover surveys in order to estimate fractional ground cover in the Australian arid zone. To meet this aim, we addressed two key objectives: (1) Determining how spectral surveys and traditional step-point sampling compare when conducted at the same spatial scale and (2) comparing these two methods to current Australian satellite-derived fractional cover products. Across seven arid, sparsely vegetated survey sites, six 500-m transects were established. Ground cover reflectance was recorded taking continuous hyperspectral readings along each transect while step-point surveys were conducted along the same transects. Both measures of ground cover were converted into proportions of photosynthetic vegetation, non-photosynthetic vegetation, and bare soil for each site. Comparisons were made of the proportions of photosynthetic vegetation, non-photosynthetic vegetation, and bare soil derived from both in situ methods as well as MODIS and Landsat fractional cover products. We found strong correlations between fractional cover derived from hyperspectral and step-point sampling conducted at the same spatial scale at our survey sites. Comparison of the in situ measurements and image-derived fractional cover products showed that overall, the Landsat product was strongly related to both in situ methods for non-photosynthetic vegetation and bare soil whereas the MODIS product was strongly correlated with both in situ methods for photosynthetic vegetation. This study demonstrates the potential of the spectral transect method, both in its ability to produce results comparable to the traditional transect measures, but also in its improved objectivity and relative logistic ease. Future efforts should be made to include spectral ground cover sampling as part of Australia’s plan to produce calibration and validation datasets for remotely sensed products.

Time to "Rewet the Swamp" – Application of Georgian Data Cube to Elucidate Drainage Patterns and Potential for Wet Agriculture and Forestry on Kolkheti Lowland

2021 ◽  
Author(s):  
Izolda Matchutadze ◽  
Aliosha Bakuridze ◽  
Ira Abuladze ◽  
Nana Shakarishvili ◽  
Mamuka Gvilava
Keyword(s):  
High Water ◽  
Bare Soil ◽  
Data Cube ◽  
Biofuel Production ◽  
The Black Sea ◽  
Vegetation Removal ◽  
Fractional Cover ◽  
Drainage Patterns ◽  
Water Detection ◽  
Black Sea Coast

<p>It was established recently that gravity drainage is inefficient on Kolkheti Lowland along the Black Sea coast of Georgia and that novel approaches are urgently recommend, such as implementing rewetting schemes to restore ecosystem services and enhance economic values of these areas through wet agriculture, biofuel production with native wetland species, and/or afforestation, to achieve sustainable outcomes in both ecologic and economic terms. Water Detection, Fractional Cover and Urbanization remote sensing tools, provided by Georgian Data Cube (comprising Landsat sensor Analysis Ready Data), developed recently with UNEP/GRID support, were applied on multi-year timescale basis for Kolkheti lowland to identify priority areas with high potential for rewetting. Water Detection tool allowed establishment of low effectiveness drainage areas, as demonstrated by high cumulative values for the presence of water, indicating water-logged areas as potential intervention sites for wet agroforestry. Water Detection combined with Fractional Cover tool allowed comparative analysis of non-photosynthetic vegetation and bare soil areas versus high water detection areas to single out those lands on the Kolkheti lowland, where drainage seems effective and dry agriculture is pursued versus those lands where drainage is not effective and dry agriculture is not actually happening. Urbanization tool can also be applied to detect human activities, such as agricultural activities, visualising those areas, which are subjected to active vegetation removal on an annual basis due to crop harvesting and those areas, where vegetation was not removed, staying vegetated most of the time, interpreted as abandoned agricultural lands. Regular patters combining non-use agricultural with cumulative water covered areas could thus help locate candidate sites for piloting wet agriculture on Kolkheti Lowland in Georgia. In addition to sustainable economic practices, rewetting could certainly benefit core ecological areas of Kolkheti Lowland, protected by both national designation as Kolkheti National Park and international designation as Central Kolkheti Ramsar Site.</p>

Growth and yield of okra (Abelmoschus esculentus (L.) Moench) grown in the marginal upland area of Sta. Rita, Samar as influenced by different planting densities and mulching materials

2017 ◽  
pp. 44-54
Author(s):  
Zenaida Gonzaga ◽  
Warren Obeda ◽  
Ana Linda Gorme ◽  
Jessie Rom ◽  
Oscar Abrantes ◽  
...  
Keyword(s):  
Bare Soil ◽  
Abelmoschus Esculentus ◽  
Growth And Yield ◽  
Planting Density ◽  
Rice Hull ◽  
Plastic Mulch ◽  
Lady’S Finger ◽  
Materials Used ◽  
Set Up ◽  
A Minor

Okra or Lady’s finger, botanically known as Abelmoschus esculentus (L.) Moench, is a tropical and sub-tropical indigenous vegetable crop commonly grown for its fibrous, slimy, and nutritious fruits and consumed by all classes of population. It has also several medicinal and economic values. Despite its many uses and potential value, its importance is under estimated, under-utilized, and considered a minor crop and little attention was paid to its improvement. The study was conducted to evaluate the effects of different planting densities and mulching materials on the growth and yield of okra grown in slightly sloping area in the marginal uplands in Sta. Rita, Samar, Philippines. A split-plot experiment was set up with planting density as main plot and the different mulching materials as the sub-plot which were: unmulched or bare soil, rice straw, rice hull, hagonoy and plastic mulch. Planting density did not significantly affect the growth and yield of okra. Regardless ofthe mulching materials used, mulched plants were taller and yielded higher compared to unmulched plants. Moreover, the use of plastic mulch resulted to the highest total fruit yield. The results indicate the potential of mulching in increasing yield and thus profitability of okra production under marginal upland conditions.

Landscape Change in the Steppe of Algeria South-West Using Remote Sensing

2018 ◽  
Vol 18 (1) ◽  
pp. 41-52
Author(s):  
Tayeb Sitayeb ◽  
Ishak Belabbes
Keyword(s):  
Remote Sensing ◽  
Social Systems ◽  
Bare Soil ◽  
Climatic Conditions ◽  
Landscape Dynamics ◽  
Landsat 8 ◽  
Natural Ecosystems ◽  
Stipa Tenacissima ◽  
Steppe Species ◽  
Sparse Vegetation

Abstract Landscape dynamics is the result of interactions between social systems and the environment, these systems evolving significantly over time. climatic conditions and biophysical phenomena are the main factors of landscape dynamics. Also, currently man is responsible for most changes affecting natural ecosystems. The objective of this work is to study the dynamics of a typical landscape of western Algeria in time and space, and to map the distribution of vegetation groups constitute the vegetation cover of this ecosystem. as well as using a method of monitoring the state of a fragile ecosystem by remote sensing to understand the processes of changes in this area. The steppe constitutes a large arid area, with little relief, covered with low and sparse vegetation. it lies between the annual isohyets of 100 to 400 mm, subjected to a very old human exploitation with an activity of extensive breeding of sheep, goats, and camels. Landsat satellite data were used to mapping vegetation groups in the Mecheria Steppe at a scale of 1: 300,000. Then, a comparison was made between the two maps obtained by a classification of Landsat-8 sensor Operational Land Imager (OLI) acquired on March 18, 2014, and Landsat-5 sensor Thematic Mapper (TM) acquired on April 25, 1987. The results obtained show the main changes affecting the natural distribution of steppe species, a strong change in land occupied by the Stipa tenacissima steppe with 65% of change, this steppe is replaced by Thymelaea microphylla, Salsola vermiculata, lygeum spartum and Peganum harmala steppe. an absence from the steppe Artemisia herba-alba that has also been replaced by the same previous steppes species. The groups with Quercus ilex and Juniperus phoenicea are characterized by a strong regression that was lost 60% of its global surface and transformed by steppe to stipa tenacissima and bare soil.

Bare soil and reed canary grass ecosystem respiration in peat extraction sites in Eastern Finland

Tellus B ◽  
2008 ◽  
Vol 60 (2) ◽  
Author(s):  
N. J. Shurpali ◽  
N. P. Hyvönen ◽  
J. T. Huttunen ◽  
C. Biasi ◽  
H. Nykänen ◽  
...  
Keyword(s):  
Ecosystem Respiration ◽  
Bare Soil ◽  
Reed Canary Grass ◽  
Peat Extraction ◽  
Canary Grass ◽  
Eastern Finland

Morphologic and Engineering Characteristics of East Wasit Watersheds Feeding the Al-Shewicha Trough in Iraq

2020 ◽  
Vol 55 (1) ◽  
Author(s):  
Mohammed S. Shamkhi ◽  
Jasim Mohammed Ridha Azee ◽  
Ali A. Abdul-Sahib
Keyword(s):  
Peak Flow ◽  
Flood Hazard ◽  
Bare Soil ◽  
Elongation Ratio ◽  
High Concentration ◽  
Large Area ◽  
Coarse Texture ◽  
Loam Soil ◽  
High Runoff ◽  
Group B

The Al-Shewicha Trough represents a serious flood hazard to Kut City (the capital of Wasit Province, Iraq) and to the other cities along the Tigris River downstream Kut Barrage, especially in heavy monsoon years. In this study, The Geographic Information System software ArcGIS was used in the morphologic analysis of six river basins that represent the main feeding sources for the Al-Shewicha Trough. The results revealed that the high values for the greatest length of Basins 1, 5, and 6 meant that these watersheds had high concentration time (tc) values, which delay peak flow. All basins consisted of very coarse and permeable subsurface strata that were of coarse texture. Circularity ratio form factor and elongation ratio suggested an elongated shape for all basins with lower peak flow and long duration. Analyses of soil data demonstrated that the soil type that covered a large area was loam soil (classified as hydrologic soil group B), which indicates that all basins had low permeability and high runoff. The predominant land use was bare soil, and all basins had a covering of poor vegetation, which highlighted the fact that basins were highly susceptible to erosion, thus resulting in the generation of higher sedimentation.

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