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T. J. Sauer - One of the best experts on this subject based on the ideXlab platform.
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Crop Residue effects on surface radiation and energy balance — review
Theoretical and Applied Climatology, 1996Co-Authors: R. Horton, K. L. Bristow, G. J. Kluitenberg, T. J. SauerAbstract:Crop Residues alter the surface properties of soils. Both shortwave albedo and longwave emissivity are affected. These are linked to an effect of Residue on surface evaporation and water content. Water content influences soil physical properties and surface energy partitioning. In summary, Crop Residue acts to soil as clothing acts to skin. Compared to bare soil, Crop Residues can reduce extremes of heat and mass fluxes at the soil surface. Managing Crop Residues can result in more favorable agronomic soil conditions. This paper reviews research results of the quantity, quality, architecture, and surface distribution of Crop Residues on soil surface radiation and energy balances, soil water content, and soil temperature.
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Crop Residue Effects on Surface Radiation and Energy Balance - Review
Theoretical and Applied Climatology, 1996Co-Authors: R. Horton, K. L. Bristow, G. J. Kluitenberg, T. J. SauerAbstract:Crop Residues alter the surface properties of soils. Both shortwave albedo and longwave emissivity are affected. These are linked to an effect of Residue on surface evaporation and water content. Water content influences soil physical properties and surface energy partitioning. In summary, Crop Residue acts to soil as clothing acts to skin. Compared to bare soil, Crop Residues can reduce extremes of heat and mass fluxes at the soil surface. Managing Crop Residues can result in more favorable agronomic soil conditions. This paper reviews research results of the quantity, quality, architecture, and surface distribution of Crop Residues on soil surface radiation and energy balances, soil water content, and soil temperature.
Craig S. T. Daughtry - One of the best experts on this subject based on the ideXlab platform.
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IGARSS - Assessing Crop Residue cover when scene moisture conditions change
2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2015Co-Authors: Craig S. T. Daughtry, Miguel QuemadaAbstract:Crop Residues protect the soil against erosion and reduce agrochemicals in runoff water. Crop Residues and soils are spectrally different in the absorption features associated with cellulose and lignin. Our objectives were to: (1) assess the effects of soil and Crop Residue water contents on the remotely sensed estimates of Crop Residue cover and (2) propose a method to mitigate these effects. Reflectance spectra of diverse Crops and soils were acquired in the laboratory and the analyses was extended to agricultural fields with different Crop Residue covers and a wide range of moisture conditions. The slope of the linear relationship with the Cellulose Absorption Index was very sensitive to moisture conditions, whereas the slope of the Shortwave Infrared Normalized Difference Residue Index was altered in a lesser extent. Water indices that provided reliable estimates of the water content could be used to estimate Crop Residue cover corrected by moisture conditions.
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IGARSS - Assessment of spectral indices for Crop Residue cover estimation
2010 IEEE International Geoscience and Remote Sensing Symposium, 2010Co-Authors: Guy Serbin, Craig S. T. Daughtry, E. Raymond Hunt, David J. Brown, Gregory W. Mccarty, Paul C. DoraiswamyAbstract:The quantification of surficial Crop Residue (nonphotosynthetic vegetation) cover is important for assessing agricultural tillage practices, rangeland health, and brush fire hazards. The Cellulose Absorption Index (CAI) and the Shortwave Infrared Normalized Difference Residue Index (SINDRI) are two spectral indices that have shown promise for remote estimation of Crop Residue cover. CAI and SINDRI utilize three and two spectral bands, respectively, rendering the latter less expensive to implement in future satellite sensors. This study shows that while CAI always contrasts well among soils, Crop Residues, and live vegetation, this is not always the case for SINDRI. A small number of surficial soil samples had positive SINDRI values that have reduced contrasts among Crop Residues. Some of these soils were biased by SINDRI-positive component minerals. As such, SINDRI is less applicable for remote Crop Residue cover estimation, even with reduced implementation costs.
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effect of soil spectral properties on remote sensing of Crop Residue cover
Soil Science Society of America Journal, 2009Co-Authors: Guy Serbin, Craig S. T. Daughtry, David J. Brown, Raymond E Hunt, Gregory W. MccartyAbstract:Conservation tillage practices often leave appreciable amounts of Crop Residues on soil surfaces after harvesting and generally improve soil structure, enhance soil organic C (SOC) content, and reduce soil erosion. Remote sensing methods have shown great promise in efficiently estimating Crop Residue cover, and thus inferring soil tillage intensity. Furthermore, these tillage intensity estimates can be used in soil C models. Reflectance spectra of more than 4200 soils and 80 Crop Residues were measured in the laboratory across the 350- to 2500-nm wavelength region. Six remote sensing spectral indices were used to estimate Crop Residue cover: the Cellulose Absorption Index (CAI), the Lignin-Cellulose Absorption Index (LCA), the Normalized Difference Tillage Index (NDTI), the Normalized Difference Senescent Vegetation Index (NDSVI), and the Normalized Difference Indices 5 and 7 (NDI5 and NDI7, respectively). Soil mineralogy and SOC affected these spectral indices for Crop Residue cover more than soil taxonomic order, which generally had little effect on spectral reflectance. The values of the spectral indices for soils were similar within Land Resource Regions and, specifically, for Major Land Resource Areas. The CAI showed the best separation between soils and Residues, followed by LCA and NDTI. Although NDSVI, NDI5, and NDI7 had significant overlaps between soil and Residue index values, assessments of Crop Residue cover classes may be possible with local calibrations. Future satellite sensors should include appropriate bands for assessing Crop Residue and nonphotosynthetic vegetation.
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Remote sensing of Crop Residue cover and soil tillage intensity
Handbook of Environmental Chemistry Volume 5: Water Pollution, 2006Co-Authors: Craig S. T. Daughtry, A. J. Stern, E. R. Hunt, J. E. Mcmurtrey, P C Doraiswamy, John H PruegerAbstract:Management of plant litter or Crop Residues in agricultural fields is an important consideration for reducing soil erosion and increasing soil organic C. Current methods of quantifying Crop Residue cover are inadequate for characterizing the spatial variability of Residue cover within fields or across large regions. Our objectives were to evaluate several spectral indices for measuring Crop Residue cover using satellite multispectral and hyperspectral data and to categorize soil tillage intensity in agricultural fields. Landsat Thematic Mapper (TM) and EO-1 Hyperion imaging spectrometer data were acquired over agricultural fields in central Iowa in May and June 2004. Crop Residue cover was measured in corn (Zea mays L.) and soybean (Glycine max Merr.) fields using line-point transects. Spectral Residue indices using Landsat TM bands were weakly related to Crop Residue cover. With the Hyperion data, Crop Residue cover was linearly related to the cellulose absorption index (CAI), which measures the relative intensity of cellulose and lignin absorption features near 2100 nm. Coefficients of determination (r2) for Crop Residue cover as a function of CAI were 0.85 for the May and 0.77 for the June Hyperion data. Three tillage intensity classes, corresponding to intensive (30% cover) tillage, were correctly identified in 66-68% of fields. Classification accuracy increased to 80-82% for two classes, corresponding to conventional (intensive + reduced) and conservation tillage. By combining information on previous season's (2003) Crop classification with Crop Residue cover after planting in 2004, an inventory of soil tillage intensity by previous Crop type was generated for the whole Hyperion scene. Regional surveys of soil management practices that affect soil conservation and soil C dynamics are possible using advanced multispectral or hyperspectral imaging systems.
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Assessing Crop Residue cover using shortwave infrared reflectance
Remote Sensing of Environment, 2004Co-Authors: Craig S. T. Daughtry, E. R. Hunt, J. E. McmurtreyAbstract:Management of Crop Residues is an important consideration for reducing soil erosion and increasing soil organic carbon. Current methods of measuring Residue cover are inadequate for characterizing the spatial variability of Residue cover over large fields. The objectives of this research were to determine the spectral reflectance of Crop Residues and soils and to assess the limits of discrimination that can be expected in mixed scenes. Spectral reflectances of dry and wet Crop Residues plus three diverse soils were measured over the 400–2400 nm wavelength region. Reflectance values for scenes with varying proportions of Crop Residues and soils were simulated. Additional spectra of scenes with mixtures of Crop Residues, green vegetation, and soil were also acquired in corn, soybean, and wheat fields with different tillage treatments. The spectra of dry Crop Residues displayed a broad absorption feature near 2100 nm, associated with cellulose-lignin, that was absent in spectra of soils. Crop Residue cover was linearly related (r 2 =0.89) to the Cellulose Absorption Index (CAI), which was defined as the relative depth of this absorption feature. Green vegetation cover in the scene attenuated CAI, but was linearly related to the Normalized Difference Vegetation Index (NDVI, r 2 =0.93). A novel method is proposed to assess soil tillage intensity classes using CAI and NDVI. Regional surveys of soil
Safya Menasseri-aubry - One of the best experts on this subject based on the ideXlab platform.
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Changes during winter in water-stable aggregation due to Crop Residue quality
Soil Use and Management, 2012Co-Authors: C. Le Guillou, D.a. Angers, Philippe Leterme, Safya Menasseri-aubryAbstract:There is a need to develop practices that contribute to increased water-stable aggregation (WSA) during winter in a humid temperate climate when soil is particularly prone to water erosion. Our objectives were to determine the effects of Crop Residue quality on WSA during winter and to relate these effects to biochemical indicators of fungal and bacterial biomass. Three graminae Crop Residues were selected for their different C/N ratios and biochemical characteristics (green oat Residues, C/N = 18.8
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Differential and successive effects of Residue quality and soil mineral N on water-stable aggregation during Crop Residue decomposition
Soil Biology and Biochemistry, 2011Co-Authors: C. Le Guillou, D.a. Angers, Philippe Leterme, Safya Menasseri-aubryAbstract:Residue quality has been shown to influence soil water-stable aggregation (WSA) during Crop Residue decomposition, but there is still little information about its interactive effect with soil mineral N availability. The aim of this study was to determine the effect of soil mineral N on WSA during the decomposition of two high-C/N Crop Residues (wheat straw with C/N = 125.6 and miscanthus straw with C/N = 311.3). The two Crop Residues were combined with three mineral N addition rates (0, 60, and 120 mg N kg−1 dry soil). Respiration, soil mineral N content, and WSA (expressed as mean-weight diameter, MWD) were measured on several dates during a 56-d incubation. The effect of decomposing Crop Residues on WSA followed two phases. (i) Between 0 and 7 d, the increase in WSA was related to intrinsic Residue quality with higher decomposability of the wheat straw resulting in higher WSA. (ii) Thereafter, and until the end of the experiment, mineral N addition rates had a predominant but negative influence on WSA. In this second phase, the average MWD of Residue-treated soils was 0.92, 0.55, and 0.44 mm for the 0, 60 and 120 mg N kg−1 dry soil addition rates, respectively. Mineral N addition which did result in higher Crop Residue decomposition did not lead to higher WSA. WSA during Crop Residue decomposition is therefore not simply positively related to the induced microbial activity, and changes in microbial community composition with differential effects on WSA must be involved. The impact of high-C/N Crop Residues inputs on WSA, initially assumed to be low, could actually be strong and long-lasting in situations with low soil mineral N content.
Rattan Lal - One of the best experts on this subject based on the ideXlab platform.
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Crop Residue removal impacts on soil productivity and environmental quality
Critical Reviews in Plant Sciences, 2009Co-Authors: Humberto Blancocanqui, Rattan LalAbstract:Crop Residues are a potential source of renewable feedstocks for cellulosic ethanol production because of their high cellulose content and easy availability. Indiscriminate removal as biofuel may, however, have adverse impacts on soil, environment, and Crop production. This article reviews available information on the impacts of Crop Residue removal on soil properties, Crop yields, and soil erosion across a wide range of soils and ecosystems. It explicitly synthesizes data on the independent impacts of Crop Residue removal on soil and environment rather than on the interrelated tillage-Crop-Residue management impacts. Published literature shows that Residue removal adversely impacts near-surface soil physical, chemical, and biological properties. Unmulched soils are prone to particle detachment, surface sealing, crusting, and compaction. Residue removal reduces input of organic binding agents essential to formation and stability of aggregates. It also closes open-ended biochannels by raindrop impacts and reduces water infiltration, saturated/unsaturated hydraulic conductivity, and air permeability, and thereby increases runoff/soil erosion and transport of non-point source pollutants (e.g., sediment and chemicals). Residue removal accelerates evaporation, increases diurnal fluctuations in soil temperature, and reduces input of organic matter needed to improve the soils' ability to retain water. It reduces macro- (e.g., K, P, N, Ca, and Mg) and micronutrient (e.g., Fe, Mn, B, Zn, and S) pools in the soil by removing nutrient-rich Residue materials and by inducing losses of soil organic matter (SOM)-enriched sediments in runoff. Residue removal drastically reduces earthworm population and microbial carbon (C) and nitrogen (N) biomass. It adversely affects agronomic production by altering the dynamics of soil water and temperature regimes. The short-term (<10 yr) data show nevertheless that Residue removal may not always degrade soil physical properties and decrease Crop yields in the short term depending on the soil type, topography, and fluctuations in annual weather conditions. Sloping and erosion-prone soils are more rapidly and adversely affected by Residue removal than those on flat terrains with heavy texture and poorly drained conditions. Sloping terrains are not only highly susceptible to water and wind erosion but also to tillage erosion. In these soils, therefore, a fraction of the total Crop Residue produced may be available for biofuel production and other expanded uses. Standard guidelines on when, where, and how much Residues to remove need to be, however, established. Modeling rates of Residue removal are presently based on the needs of soil cover to control erosion without consideration to maintaining SOM and nutrient pools, enhancing soil physical, chemical, and biological quality, and sustaining Crop production. Threshold levels of Residue removal must be assessed for principal soil types based on the needs to maintain or enhance soil productivity and improve environmental quality. For those soils in which some Residues are removed, best management practices (e.g., cover Crops, diverse Crop rotations, and manure application) must be adopted to minimize adverse impacts of Residue removal. Because indiscriminate harvesting of Crop Residues for biofuel may deteriorate soil properties, reduce Crop yields, and degrade the environment, there exists an urgent research need for developing alternative sustainable renewable energy feedstocks (e.g., warm season grasses and short-rotation woody Crops).
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Crop Residue and tillage effects on carbon sequestration in a luvisol in central ohio
Soil & Tillage Research, 1999Co-Authors: Sjoerd W Duiker, Rattan LalAbstract:Abstract Soils play a key role in the global carbon cycle. They can be a source or a sink of carbon and influence CO 2 concentrations in the atmosphere. In order to calculate the carbon budget of a region, the effect of soil management practices on carbon sequestration in soils needs to be quantified. Objectives of this experiment were to determine: (i) the effects of ridge till, plow till and no-till on the soil organic carbon (SOC) pool; (ii) the SOC loss or sequestration for mulch rates of 0–16 Mg ha −1 year −1 wheat ( Triticum aestivum L.) straw applied in combination with each tillage method, and (iii) impacts of tillage and Crop Residue treatments on soil physical quality, including aggregation and porosity. The experiment was initiated in 1989 on a Crosby silt loam (Stagnic Luvisol) in Central Ohio. Seven years after initiation of the experiment, there was a positive, linear effect of Residue application rate on SOC contents in all tillage treatments. In the eighth year of the experiment these trends were confirmed for plow and no-till, but not for ridge till. Linear-regression equations, relating SOC content for the 0–10 cm soil depth to mulch rate, were: for no-till: SOC (Mg ha −1 ) = 15.21 + 0.32 [Residue (Mg ha −1 year −1 )] ( r = 0.68) and for plow till: SOC = 11.95 + 0.27 [Residue] ( p = 0.72). The carbon conversion efficiencies were 8% per year for plow till and 10% per year for no-till. Detailed sampling at different depths revealed that increases in SOC content were only significant for the 0–5 cm depths of plow and no-till treatments. Effects of Crop Residue application on water stable aggregation in the 0–10 cm layer were most pronounced with plow till and ridge till but not with no-till. Water retention characteristics, a measure of pore size distribution, was not influenced by tillage system, but Crop Residue application had a significant effect on water retention in the 0–10 cm layer at matric suctions of 30–300 kPa. This means that Residue application increased maCropores of diameters 1–10 μm. It is concluded that, depending on the amount of Crop Residue returned to the soil, the large numbers of farmers converting from plow to no-till cultivation in the Corn Belt may create an important sink for atmospheric CO 2 .
C S T Daughtry - One of the best experts on this subject based on the ideXlab platform.
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spectral indices to improve Crop Residue cover estimation under varying moisture conditions
Remote Sensing, 2016Co-Authors: Miguel Quemada, C S T DaughtryAbstract:Crop Residues on the soil surface protect the soil against erosion, increase water infiltration and reduce agrochemicals in runoff water. Crop Residues and soils are spectrally different in the absorption features associated with cellulose and lignin. Our objectives were to: (1) assess the impact of water on the spectral indices for estimating Crop Residue cover (fR); (2) evaluate spectral water indices for estimating the relative water content (RWC) of Crop Residues and soils; and (3) propose methods that mitigate the uncertainty caused by variable moisture conditions on estimates of fR. Reflectance spectra of diverse Crops and soils were acquired in the laboratory over the 400–2400-nm wavelength region. Using the laboratory data, a linear mixture model simulated the reflectance of scenes with various fR and levels of RWC. Additional reflectance spectra were acquired over agricultural fields with a wide range of Crop Residue covers and scene moisture conditions. Spectral indices for estimating Crop Residue cover that were evaluated in this study included the Normalized Difference Tillage Index (NDTI), the Shortwave Infrared Normalized Difference Residue Index (SINDRI) and the Cellulose Absorption Index (CAI). Multivariate linear models that used pairs of spectral indices—one for RWC and one for fR—significantly improved estimates of fR using CAI and SINDRI. For NDTI to reliably assess fR, scene RWC should be relatively dry (RWC < 0.25). These techniques provide the tools needed to monitor the spatial and temporal changes in Crop Residue cover and help determine where additional conservation practices may be required.
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an improved aster index for remote sensing of Crop Residue
Remote Sensing, 2009Co-Authors: Guy Serbin, Gregory W. Mccarty, Raymond E Hunt, C S T Daughtry, P C DoraiswamyAbstract:Unlike traditional ground-based methodology, remote sensing allows for the rapid estimation of Crop Residue cover (fR). While the Cellulose Absorption Index (CAI) is ideal for fR estimation, a new index, the Shortwave Infrared Normalized Difference Residue Index (SINDRI), utilizing ASTER bands 6 and 7, is proposed for future multispectral sensors and would be less costly to implement. SINDRI performed almost as well as CAI and better than other indices at five locations in the USA on multiple dates. A minimal upgrade from one broad band to two narrow bands would provide fR data for carbon cycle modeling and tillage verification.
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mitigating the effects of soil and Residue water contents on remotely sensed estimates of Crop Residue cover
Remote Sensing of Environment, 2008Co-Authors: C S T Daughtry, E. R. HuntAbstract:Crop Residues on the soil surface decrease soil erosion and increase soil organic carbon and the management of Crop Residues is an integral part of many conservation tillage systems. Current methods of measuring Residue cover are inadequate for characterizing the spatial variability of Residue cover over large fields. The objectives of this research were to determine the effects of water content on the remotely sensed estimates of Crop Residue cover and to propose a method to mitigate the effects of water content on remotely sensed estimates of Crop Residue cover. Reflectance spectra of Crop Residues and soils were measured in the lab over the 400-2400 nm wavelength region. Reflectance of scenes with various Residue cover fractions and water contents was simulated using a linear mixture model. Additional spectra of scenes with mixtures of Crop Residues and soil were also acquired in corn, soybean, and wheat fields with different tillage treatments and different water content conditions. Crop Residue cover was linearly related to the cellulose absorption index (CAI), which was defined as the relative intensity of an absorption feature near 2100 nm. Water in the Crop Residue significantly attenuated CAI and changed the slope of the Residue cover vs. CAI relationship. Without an appropriate correction, Crop Residue covers were underestimated as scene water content increased. Spectral vegetation water indices were poorly related to changes in the water contents of Crop Residues and soils. A new reflectance ratio water index that used the two bands located on the shoulders of the cellulose absorption feature to estimate scene water conditions was proposed and tested with data from corn, soybean, and wheat fields. The ratio water index was used to describe the changes in the slope of Crop Residue cover vs. CAI and improve the predictions of Crop Residue cover. These results indicate that spatial and temporal adjustments in the spectral estimates of Crop Residue cover are possible. Current mutispectral imaging systems will not provide reliable estimates of Crop Residue cover when scene water content varies. Hyperspectral data are not required, because the three narrow bands that are used for both CAI and the scene moisture correction could be incorporated in advanced multispectral sensors. Thus, regional surveys of soil conservation practices that affect soil carbon dynamics may be feasible using either advanced multispectral or hyperspectral imaging systems.