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Full-Text Articles in Physical Sciences and Mathematics

Mgrre_Thinsections_05_A_76, Mgrre Nov 2022

Mgrre_Thinsections_05_A_76, Mgrre

Thin Sections

No abstract provided.


How Impervious Are Solar Arrays? On The Need For Geomorphic Assessment Of Energy Transition Technologies, Charles Shobe Nov 2022

How Impervious Are Solar Arrays? On The Need For Geomorphic Assessment Of Energy Transition Technologies, Charles Shobe

Faculty & Staff Scholarship

Staying within manageable global temperature rise scenarios (i.e., 1.5° C) requires rapid decarbonization of energy sources. Research on the energy transition typically focuses on engineering, socioeconomic, and political challenges related to implementation of renewable energy technologies. Yet many facets of the energy transition are intricately intertwined with earth surface processes. Projects that advance the energy transition affect surface hydrology, sediment transport, and landscape evolution. Geomorphic processes likewise set the feasibility of energy transition projects. Here I use the lens of a recent policy debate to examine a case study that illustrates the key role of surface processes in determining the …


Unexpected Opportunities For Manatee (Trichechus Manatus Latirostris) Education And Citizen Science, Yvanna M. Strait, Amy Hirons Nov 2022

Unexpected Opportunities For Manatee (Trichechus Manatus Latirostris) Education And Citizen Science, Yvanna M. Strait, Amy Hirons

Marine & Environmental Sciences Faculty Articles

The Florida manatee (Trichechus manatus latirostris) mainly resides within the state's coastal waters, but sharing this habitat with thousands of watercrafts, either registered, unregistered, or visiting, has proven challenging for its survival. The future of manatee research among scientists and citizen scientists has strong potential. By taking advantage of venues of opportunity such as boat shows, not only is local population data gathered, but a stronger positive relationship with the public is forged. When people feel they have a stake in the conservation of a species or habitat, they will likely become and remain engaged.


Generative Spatio-Temporal And Multimodal Analysis Of Neonatal Pain, Md Sirajus Salekin Nov 2022

Generative Spatio-Temporal And Multimodal Analysis Of Neonatal Pain, Md Sirajus Salekin

USF Tampa Graduate Theses and Dissertations

Neonates can not express their pain like an adult person. Due to the lacking of proper muscle growth and inability to express non-verbally, it is difficult to understand their emotional status. In addition, if the neonates are under any treatment or left monitored after any major surgeries (post-operative), it is more difficult to understand their pain due to the side effect of medications and the caring system (i.e. intubated, masked face, covered body with blanket, etc.). In a clinical environment, usually, bedside nurses routinely observe the neonate and measure the pain status following any standard clinical pain scale. But current …


Mgrre_Thinsections_05_A_75, Mgrre Nov 2022

Mgrre_Thinsections_05_A_75, Mgrre

Thin Sections

No abstract provided.


The Assembly Of Mammalian Swi/Snfchromatin Remodeling Complexes Is Regulated By Lysine-Methylation Dependent Proteolysis, Pengfei Guo, Nam Hoang, Joseph Sanchez, Elaine H. Zhang, Keshari Rajawasam, Kristiana Trinidad, Hong Sun, Hui Zhang Nov 2022

The Assembly Of Mammalian Swi/Snfchromatin Remodeling Complexes Is Regulated By Lysine-Methylation Dependent Proteolysis, Pengfei Guo, Nam Hoang, Joseph Sanchez, Elaine H. Zhang, Keshari Rajawasam, Kristiana Trinidad, Hong Sun, Hui Zhang

Chemistry and Biochemistry Faculty Research

The assembly of mammalian SWI/SNF chromatin remodeling complexes is developmentally programed, and loss/mutations of SWI/SNF subunits alter the levels of other components through proteolysis, causing cancers. Here, we show that mouse Lsd1/Kdm1a deletion causes dramatic dissolution of SWI/SNF complexes and that LSD1 demethylates the methylated lysine residues in SMARCC1 and SMARCC2 to preserve the structural integrity of SWI/SNF complexes. The methylated SMARCC1/SMARCC2 are targeted for proteolysis by L3MBTL3 and the CRL4DCAF5 ubiquitin ligase complex. We identify SMARCC1 as the critical target of LSD1 and L3MBTL3 to maintain the pluripotency and self-renewal of embryonic stem cells. L3MBTL3 also regulates SMARCC1/SMARCC2 proteolysis …


Hydrodynamics, Andrei Ludu Nov 2022

Hydrodynamics, Andrei Ludu

Publications

The mathematical description of the states of a fluid is based on the study of three fields defined on the domain occupied by the fluid: the velocity field V, the density ρ, and the pressure field P. These three “unknowns” are determined by integrating other five scalar equations, namely the mass conservation (continuity equation), the three components of the equation of momentum balance (Euler or Navier–Stokes), and the energy balance. This last equation needs in addition information about the thermodynamics of the fluid, so it may need to be supplied with some equation of state. In addition to these five …


Kinematics Of Fluids, Andrei Ludu Nov 2022

Kinematics Of Fluids, Andrei Ludu

Publications

The goal of this chapter is to discuss the general frame of hydrodynamics, like particle trajectories (path lines), streamlines, streak lines, free surfaces, and fluid surfaces, and to compare their behavior in the Eulerian and Lagrangian frames. The following sections and chapters proceed on the assumption that the fluid is practically continuous and homogeneous in structure. Of course, the concept of continuum is an abstraction that does not take into account the molecular and nuclear structure of matter. In that, we assume that the properties of the fluid do not change if we consider smaller and smaller amounts of matter …


Photoionization Energetics And Dissociation Pathways Of Hydroperoxyethyl Formate Produced In The Reaction Of Ch3Choo + Formic Acid, Vincent J. Esposito, Trent A. Mchenry, Marsha I. Lester Nov 2022

Photoionization Energetics And Dissociation Pathways Of Hydroperoxyethyl Formate Produced In The Reaction Of Ch3Choo + Formic Acid, Vincent J. Esposito, Trent A. Mchenry, Marsha I. Lester

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The bimolecular reaction of Criegee intermediates, zwitterionic carbonyl oxide species produced in alkene ozonolysis, with organic acids leads to formation of functional hydroperoxides implicated in the generation of atmospheric aerosols. This theoretical study using high-level explicitly correlated coupled-cluster theory examines the low energy conformers of hydroperoxyethyl formate [HOOCH(CH3)OCHO, HPEF] formed in the bimolecular reaction of CH3CHOO, a simple alkyl-substituted Criegee intermediate, with formic acid, and the detection of HPEF via photoionization. The vertical and adiabatic ionization energies of HPEF are computed, along with the pathways for dissociative ionization that produce HO2 or OCHO fragments with …


Iterative Time-Domain Method For Resolving Multiple Gravitational Wave Sources In Pulsar Timing Array Data, Yi Qian Qian, Soumya D. Mohanty, Yan Wang Nov 2022

Iterative Time-Domain Method For Resolving Multiple Gravitational Wave Sources In Pulsar Timing Array Data, Yi Qian Qian, Soumya D. Mohanty, Yan Wang

Physics & Astronomy Faculty Publications

The sensitivity of ongoing searches for gravitational wave (GW) sources in the ultra-low-frequency regime (10(-9) Hz to 10(-7) Hz) using pulsar timing arrays (PTAs) will continue to increase in the future as more well-timed pulsars are added to the arrays. It is expected that next-generation radio telescopes, namely, the Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST) and the Square Kilometer Array (SKA), will grow the number of well-timed pulsars to O(10(3)). The higher sensitivity will result in greater distance reach for GW sources, uncovering multiple resolvable GW sources in addition to an unresolved population. Data analysis techniques that can search for …


Aspects Of The Equivalence Between The FΜ And C Vμ Terms In Lorentz-Violating Quantum Field Theory, Sapan Karki, Brett David Altschul Nov 2022

Aspects Of The Equivalence Between The FΜ And C Vμ Terms In Lorentz-Violating Quantum Field Theory, Sapan Karki, Brett David Altschul

Faculty Publications

It is known that in Lorentz-violating effective field theory, there is a classical equivalence between certain coefficients (c and f), in spite of the fact that the operators of the two types of coefficients described appear to have opposite behaviors under CPT. This paper is a continuation of previous work extending this equivalence to the quantum level: generalizing the explicit spinorial point transformations that interconvert the c and f terms; demonstrating that the transformations do not give rise to any additional anomaly terms as the quantum level; and giving explicit prescriptions for modifying the C, P, and T operators in …


Nitrogen Response Of Spring And Winter Wheat To Biosolids Compared To Chemical Fertiliser, W. Kato, O. T. Carton, D. Mcgrath, H. Tunney, W. E. Murphy, P. O'Toole Nov 2022

Nitrogen Response Of Spring And Winter Wheat To Biosolids Compared To Chemical Fertiliser, W. Kato, O. T. Carton, D. Mcgrath, H. Tunney, W. E. Murphy, P. O'Toole

IGC Proceedings (1977-2023)

Irish sewage sludge production was over 30,000 t/year in the 1990s (EPA, Ireland, 2003). Application to agricultural land is a management option for this organic material as it results in the recycling of the nutrients they contain for crop production. The EU Directive (91/271/EEC) encourages the recycling of sewage sludge as biosolids to agriculture. However, up to 1999, only about 5 % of biosolids produced was applied to agricultural land. In this study, several biosolids and a chemical fertiliser were used to assess N availability for spring and winter wheat (Triticum aestivum,) production in a pot experiment.


Supplementation Of Cattle With Rock Phosphate And Urea Treated Straw To Improve Manure Quality And Crop Yields In The Sahel Zone Of Senegal, Maimouna Cissé, M. N’Diaye, C. M. N’Dione Nov 2022

Supplementation Of Cattle With Rock Phosphate And Urea Treated Straw To Improve Manure Quality And Crop Yields In The Sahel Zone Of Senegal, Maimouna Cissé, M. N’Diaye, C. M. N’Dione

IGC Proceedings (1977-2023)

Mineral deficiencies are a major constraint in improving animal production and crop yield in the Sahel zone (Cissé et al., 1996). Millet (Pennisetum glaucum) and groundnut (Arachis hypogaea,) are two major food and cash crops in this zone. The purpose of this study was to assess effects of supplementing grazing cattle with rock phosphate and nitrogen enriched diets on animal performances, and the effects of the application of their manure on crop yield in a pearl millet-groundnut rotational system located in N Senegal.


Total Sulphur Content And N:S Ratio As Indicators For S Deficiency In Grasses, M. Mathot, R. Lambert, B. Toussaint, A. Peeters Nov 2022

Total Sulphur Content And N:S Ratio As Indicators For S Deficiency In Grasses, M. Mathot, R. Lambert, B. Toussaint, A. Peeters

IGC Proceedings (1977-2023)

Recently, sulphur (S) deficiencies have been observed throughout Europe (Zaoh et al., 2002). Grassland covers about 50 % of the agricultural area in the European Union. In cutting regimes exports are ca 30 kg S/ha per year. Atmospheric depositions provide, at the present, ca15 kg S/ha per year and S is not considered in fertiliser programmes. Without fertilisation, the S balance at the field scale is negative and therefore some cut swards could be S deficient. Tools for determining whether the grassland is deficient are required. The utilisation of indicators based on S content and N:S ratio was …


Study Of Soil Characteristics To Estimate Sulphur Supply For Plant Growth, M. Mathot, R. Lambert, B. Toussaint, A. Peeters Nov 2022

Study Of Soil Characteristics To Estimate Sulphur Supply For Plant Growth, M. Mathot, R. Lambert, B. Toussaint, A. Peeters

IGC Proceedings (1977-2023)

During the last decades, sulphur (S) deficiencies have been observed throughout Europe (Zaoh et al., 2002). Accurate estimation of S supply by the soil-atmosphere system is required to give advice for S fertilisers. Soil is an important S source for plants and it is therefore important to evaluate supply by the soil to avoid deficiencies or excessive S fertilisation. The purpose of this preliminary study was to estimate which soil characteristics could be useful for predicting S supply by soil. Lolium multiflorum was grown on different soils in a growth chamber and S supply was correlated with soil characteristics.


Organic Matter Transformation Processes Of Soils In Native Steppe Grass Communities, E. Forró Nov 2022

Organic Matter Transformation Processes Of Soils In Native Steppe Grass Communities, E. Forró

IGC Proceedings (1977-2023)

It has been well known that higher plant density provides more effective protection for soils. However, the influence of different vegetation on the soil properties has been less well recognised. The high density of grass communities, a high number of plant species and density of roots have advantageous effects on soil properties and conditions, particularly on the organic matter cycling and structure of soils.


Characterisation Of Soil Organic Matter From Pensacola Bahiagrass Pastures Grazed For Four Years At Different Management Intensities, J. C. B. Dubeux Jr., Lynn E. Sollenberger, N. B. Comerford, Ana C. Ruggieri, K. M. Portier Nov 2022

Characterisation Of Soil Organic Matter From Pensacola Bahiagrass Pastures Grazed For Four Years At Different Management Intensities, J. C. B. Dubeux Jr., Lynn E. Sollenberger, N. B. Comerford, Ana C. Ruggieri, K. M. Portier

IGC Proceedings (1977-2023)

Soil fertility and agricultural system sustainability depend upon soil organic matter (SOM), particularly in the tropics, because of highly weathered soils and low fertiliser inputs. Because of the beneficial effects of SOM on chemical, physical, and biological soil properties, Greenland (1994) suggested that SOM is an indicator of agro-ecosystem sustainability. Pasture management may affect SOM by altering the production/decomposition ratio of residues (Johnson, 1995). The objective of this study was to characterise the SOM of Pensacola bahiagrass pastures grazed for four years at a range of management intensities.


Implications For N Transformations In Acidic Soils Of Replacing Annual-Based Legume Pastures With Lucerne-Based Pasture In Dryland Farming Systems Of Southern Australia, I. R. P. Fillery Nov 2022

Implications For N Transformations In Acidic Soils Of Replacing Annual-Based Legume Pastures With Lucerne-Based Pasture In Dryland Farming Systems Of Southern Australia, I. R. P. Fillery

IGC Proceedings (1977-2023)

The supply and demand for nitrogen (N) in annual-based pasture-crop rotations in southern Australia is often poorly synchronised, leading to large losses of inorganic N (Fillery, 2001). Perennial pasture species, particularly lucerne, are being recommended to minimise dryland salinity. The implications for N cycling of using lucerne in place of annual legumes on acidic sandy soils that are widespread have not been widely studied. Lucerne is less tolerant of acidity and could fix less N than annual legumes. Lucerne root residues mineralise at slower rates than annual pasture residues with lower N release to subsequent wheat crops (Bolger et al …


N-Mineralisation And Phosphorous: Important Elements In Decision Support For Grassland Systems, A. L. Nielsen, C. C. Hoffmann Nov 2022

N-Mineralisation And Phosphorous: Important Elements In Decision Support For Grassland Systems, A. L. Nielsen, C. C. Hoffmann

IGC Proceedings (1977-2023)

Leaching of N and P from extensively managed grasslands on organic soils varies considerably. In environmentally sensitive areas it is important to diminish leaching by appropriate agricultural management. In Denmark low grazing intensity and management without fertilisation have been given a high priority. The type of soil has not been equally in focus, and it seems that the effect of cutting, compared with grazing, results in a higher removal of nutrients (e.g. Benke et al., 1992) can be used more strategically. The objective of this case study was to combine data from management strategies with data from leaching studies …


Nitrogen Mineralisation In Situ And In Controlled Environment, F. Pálmason Nov 2022

Nitrogen Mineralisation In Situ And In Controlled Environment, F. Pálmason

IGC Proceedings (1977-2023)

Net mineralisation may be underestimated by in situ soil core methods for at least two reasons: (1) absence of plant N uptake in the soil cores, causing higher immobilisation than in intact soil. Schimel & Bennet (2004) thus concluded that plants compete effectively with microbes, as strongly indicated by cases, where net mineralisation was lower than plant uptake. (2) Gaseous losses of N2O in closed cylinders can lead to underestimation especially during long incubation periods, Abril et al. (2001) and Vor & Brumme (2002).


Effect Of Different Carbon And Nitrogen Inputs On Soil Chemical And Biochemical Properties In Maize-Based Forage Systems In Northern Italy, S. Monaco, D. Hatch, L. Dixon, C. Grignani, D. Sacco, L. Zavattaro Nov 2022

Effect Of Different Carbon And Nitrogen Inputs On Soil Chemical And Biochemical Properties In Maize-Based Forage Systems In Northern Italy, S. Monaco, D. Hatch, L. Dixon, C. Grignani, D. Sacco, L. Zavattaro

IGC Proceedings (1977-2023)

In agroecosystems, manure application and straw return affect carbon (C) and nitrogen (N) cycling and affect soil organic matter (SOM), nutrient supply and losses to the environment. We examined effects of different organic sources on crop production, N uptake and surplus and SOM in maize systems.


Seasonal Changes In The Ratio Of Microbial Biomass P To Total P In Soils Of Grazed Pastures, M. Kaneko, Y. Kurokawa, H. Tanaka, S. Suzuki Nov 2022

Seasonal Changes In The Ratio Of Microbial Biomass P To Total P In Soils Of Grazed Pastures, M. Kaneko, Y. Kurokawa, H. Tanaka, S. Suzuki

IGC Proceedings (1977-2023)

Phosphorus (P) utilisation efficiency in pasture soils is higher than in arable soils. Because there is a considerable amount of microbial biomass in the root mat layer, which is peculiar to permanent pasture, the microbial biomass P (MBP) contribution may be important in supplying soil P to pasture plants (Chen et al., 2000; He et al., 1997). In the present study, we investigated seasonal changes in MBP and other forms of P relative to total soil P in two pastures in which P uptake was estimated to be different.


Effect Of Soil Chemistry On Microbial Biodiversity And Functionality In Grassland And Tilled Soils, C. Carrigg, S. Kavanagh, D. Fay, V. O. Flaherty Nov 2022

Effect Of Soil Chemistry On Microbial Biodiversity And Functionality In Grassland And Tilled Soils, C. Carrigg, S. Kavanagh, D. Fay, V. O. Flaherty

IGC Proceedings (1977-2023)

Microorganisms are excellent indicators of soil health, because of their rapid response to environmental change. Traditional microbiology is ineffective for the study of soil, as < 1% of microorganisms are currently culturable (Torsvik et al., 1996). Nucleic acid based methods, however, allow rapid detection of organisms, or particular genes, directly from soil samples. This work investigated, using polymerase chain reaction (PCR)-based approaches, the relationship between key chemical properties and bacterial biodiversity in grassland and tilled soils, with particular emphasis on the abundance and diversity of ammonium oxidisers.


Nitrogen Leaching From Cattle, Sheep And Deer Grazed Pastures In New Zealand, Keith Betteridge, Sterwart F. Ledgard, Coby J. Hoogendoorn, M. G. Lambert, Z. A. Park, Des A. Costall, P. W. Theobald Nov 2022

Nitrogen Leaching From Cattle, Sheep And Deer Grazed Pastures In New Zealand, Keith Betteridge, Sterwart F. Ledgard, Coby J. Hoogendoorn, M. G. Lambert, Z. A. Park, Des A. Costall, P. W. Theobald

IGC Proceedings (1977-2023)

The impacts of intensified grazing in New Zealand are being reflected in declining quality of groundwater, streams and lake water. Manipulation of ratios of grazing animal species may be one way farmers can reduce nitrogen (N) emissions to ground water. The present research quantifies nitrate and ammonium leaching losses from rotationally grazed sheep, cattle and deer pastures in a common environment.


Study Of Dairy Manure N Cycling In Soil-Plant Continuum Using 15N And Other Methods, J. M. Powell, P. R. Cusick, K. A. Kelling Nov 2022

Study Of Dairy Manure N Cycling In Soil-Plant Continuum Using 15N And Other Methods, J. M. Powell, P. R. Cusick, K. A. Kelling

IGC Proceedings (1977-2023)

Ruminant livestock manure impacts on N cycling in the soil-plant continuum. Most studies of manure N cycling are short-term and rely on indirect methods, i.e. apparent N recovery, fertiliser N equivalents or incorporate 15N into ammonium-N fractions. Direct and perhaps more precise measurements may be achieved by long-term studies using 15N incorporated into all manure N components. This paper summarises results of a 6- year trial to compare indirect and direct measures of manure N uptake by corn for 3 years after application.


Changes In Nutrient Turnover And Supply During The Reversion Of Arable Land To Acid Grassland/Calluna Heathland, A. Bhogal, B. J. Chambers, R. Pywell, K. Walker Nov 2022

Changes In Nutrient Turnover And Supply During The Reversion Of Arable Land To Acid Grassland/Calluna Heathland, A. Bhogal, B. J. Chambers, R. Pywell, K. Walker

IGC Proceedings (1977-2023)

Lowland heath is of high conservation value because of the specialised and rare assemblages of plants and animals that it supports. Combinations of agricultural and urban development, and lack of appropriate management have resulted in large-scale loss and fragmentation of this habitat throughout the UK. Current UK conservation policies seek to re-create 6,000 ha of this habitat on land previously in agricultural and forestry production. Previous research indicated that high soil pH and fertility, together with a lack of propagules of heathland species, made it difficult to achieve this objective. The aim was to evaluate techniques to establish grass-Calluna …


The Effect Of A Reduction In Phosphate Application On Soil Phosphate Pools, C. Van Der Salm, J. Van Middelkoop, P. A. I. Ehlert Nov 2022

The Effect Of A Reduction In Phosphate Application On Soil Phosphate Pools, C. Van Der Salm, J. Van Middelkoop, P. A. I. Ehlert

IGC Proceedings (1977-2023)

Excessive use of manure and fertilisers in western Europe has led to high phosphorus (P) contents in many agricultural soils leading to environmental P losses by overland flow, subsurface drainage and leaching to groundwater. To stop phosphate build up in the soil and leaching to surface and ground waters, the Dutch government is gradually reducing allowable phosphate application on grassland from 130 kg/ha per year in 2005 to 90 kg/ha per year in 2015. This will lead to a reduction of the phosphate surplus from 40 in 2005 to 0 kg/ha per year. To investigate the impact of reductions in …


How Will Removal Of The Non-Organic Feed Derogation Affect Nutrient Budgets Of Organic Livestock Farms In Wales?, H. Mccalman, S. P. Cuttle Nov 2022

How Will Removal Of The Non-Organic Feed Derogation Affect Nutrient Budgets Of Organic Livestock Farms In Wales?, H. Mccalman, S. P. Cuttle

IGC Proceedings (1977-2023)

Agri-environment schemes encourage organic farming in Wales. The National Assembly Government second organic action plan has a target of 10-15% land in organic production by 2010. Although forage based, many organic livestock farmers buy in concentrate feeds, which are important sources of nutrients to the farm. The current derogation allowing organic producers up to 10% approved non-organic feed ends in 2005. Many organic farmers are beginning to make management changes to comply with this. The aims of this study were to construct simple nutrient budgets on different organic livestock farms, investigate any planned system changes, look at impacts on nutrient …


Diet Effects On Dairy Manure Nitrogen Excretion And Cycling, J. M. Powell, T. H. Misselbrook Nov 2022

Diet Effects On Dairy Manure Nitrogen Excretion And Cycling, J. M. Powell, T. H. Misselbrook

IGC Proceedings (1977-2023)

The amount and forms of (nitrogen) N excreted by ruminant livestock and post excretion manure N cycling are highly influenced by what is fed. For example, the relative amount of urinary N, faecal endogenous N of microbial and gut origin, and faecal undigested feed N is affected by how much dietary fibre and secondary compounds (e.g., tannins, polyphneolics) are consumed. Each manure N component has a different propensity for loss; for example via ammonia (NH3) volatilisation (Misselbrook et al., 2004), leaching, and cycles differently in the soil-plant continuum (Powell, 2003). We evaluated dairy diet effects on amount and forms …


Effect Of A Grazing Intensity Gradient On Primary Production And Soil Nitrogen Mineralisation In A Humid Grassland Of Western France, N. Rossignol, A. Bonis, J-B. Bouzillé Nov 2022

Effect Of A Grazing Intensity Gradient On Primary Production And Soil Nitrogen Mineralisation In A Humid Grassland Of Western France, N. Rossignol, A. Bonis, J-B. Bouzillé

IGC Proceedings (1977-2023)

Large herbivores have a major influence on the structure and the functions of humid grasslands and especially on primary production. Earlier work on the study site showed that grazing intensity was spatially varied and created a diversity of vegetation patches in the grassland (Loucougaray, 2003). The first objective of this study was to determine whether the variation in grazing intensity led to variation of primary production within the three plant communities located at three topographic levels in the grassland. The second objective was to determine whether a relationship linked primary production variation and net soil nitrogen (N) mineralisation.