As a partial conclusion, we do argue that indeed, using the T-M formula as the theoretical refere... more As a partial conclusion, we do argue that indeed, using the T-M formula as the theoretical reference is a ‘strong’ assumption which explains that a bivariate solution to elasticity is better that a monovariate one. However, beyond reflecting the “hydrological good sense”, it also reflects the visual impression from the graphs that we present in supplement. Moreover, we believe that the T-M formula’s assumptions are likely to be shared by most hydrologists, and that the T-M formula is both extremely simple and widely-used, which should turn our demonstration acceptable to many of our readers. We thank AV for his suggestion to show graphically that the TM formula implies well defined elasticities at moderate aridity conditions, and we will use this graph in the revised version.
A software to predict the impact of revegetation strategies on the Coarse Sandy Hilly Region of t... more A software to predict the impact of revegetation strategies on the Coarse Sandy Hilly Region of the Loess Plateau of China
Forest plantations can access water from some unconfined aquifers that also contain nitrate at co... more Forest plantations can access water from some unconfined aquifers that also contain nitrate at concentrations that could support hydroponic culture, but the separate effects of such additional water and nitrogen availability on tree growth have not hitherto been quantified. We demonstrate these effects using simulation modelling at two contrasting sites supporting Eucalyptus globulus Labill. or Pinus radiata D.Don plantations. The APSIM Eucalyptus and Pinus models simulated plantation growth within 2% of observed growth where the water table was at 4 m depth for eucalypts (height 28 m, MAI 32 m3 ha−1 year−1) and at 23 m for pines (height 37 m, MAI 20 m3 ha−1 year−1). In simulations without an aquifer, observed growth could only be matched using unrealistically high surface soil nitrogen (N) supply, suggesting this is an unlikely mechanism. Simulated aquifer N concentrations, evapotranspiration, and net N mineralization and leaching (emergent properties of modelling) were similar to ...
mission of the Cooperative Research Centre for Sustainable Rice Production and/or the individual ... more mission of the Cooperative Research Centre for Sustainable Rice Production and/or the individual parties to that joint venture (the " Parties "). Disclaimer The information in this publication is based on knowledge available at the time of writing. The publication is presented in good faith and has been made available by the Cooperative Research Centre for Sustainable Rice Production (Rice CRC) on the basis that recipients of the publication should make their own enquiries and obtain appropriate professional advice before relying on any information or any expression of opinion or prediction contained in this publication. Neither the joint venture known as the Cooperative Research Centre for Sustainable Rice Production (Rice CRC) nor its individual member parties accept liability for any losses, damages or costs resulting from the use of information contained in or omitted from this publication. The views expressed and the conclusions reached in this publication are those o...
The onus for monitoring crop growth from space is its ability to be applied anytime and anywhere,... more The onus for monitoring crop growth from space is its ability to be applied anytime and anywhere, to produce crop yield estimates that are consistent at both the subfield scale for farming management strategies and the country level for national crop yield assessment. Historically, the requirements for satellites to successfully monitor crop growth and yield differed depending on the extent of the area being monitored. Diverging imaging capabilities can be reconciled by blending images from high-temporal-frequency (HTF) and high-spatial-resolution (HSR) sensors to produce images that possess both HTF and HSR characteristics across large areas. We evaluated the relative performance of Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat, and blended imagery for crop yield estimates (2009–2015) using a carbon-turnover yield model deployed across the Australian cropping area. Based on the fraction of missing Landsat observations, we further developed a parsimonious framework ...
We present new global maps of the Köppen-Geiger climate classification at an unprecedented 1-km r... more We present new global maps of the Köppen-Geiger climate classification at an unprecedented 1-km resolution for the present-day (1980-2016) and for projected future conditions (2071-2100) under climate change. The present-day map is derived from an ensemble of four high-resolution, topographically-corrected climatic maps. The future map is derived from an ensemble of 32 climate model projections (scenario RCP8.5), by superimposing the projected climate change anomaly on the baseline high-resolution climatic maps. For both time periods we calculate confidence levels from the ensemble spread, providing valuable indications of the reliability of the classifications. The new maps exhibit a higher classification accuracy and substantially more detail than previous maps, particularly in regions with sharp spatial or elevation gradients. We anticipate the new maps will be useful for numerous applications, including species and vegetation distribution modeling. The new maps including the ass...
Elevated atmospheric COconcentration (eC) might reduce forest water-use, due to decreased transpi... more Elevated atmospheric COconcentration (eC) might reduce forest water-use, due to decreased transpiration, following partial stomatal closure, thus enhancing water-use efficiency and productivity at low water availability. If evapotranspiration (E) is reduced, it may subsequently increase soil water storage (ΔS) or surface runoff (R) and drainage (D), although these could be offset or even reversed by changes in vegetation structure, mainly increased leaf area index (L). To understand the effect of eCin a water-limited ecosystem, we tested whether two years of eC(~40% increase) affected the hydrological partitioning in a mature water-limited Eucalyptus woodland exposed to Free-Air COEnrichment (FACE). This timeframe allowed us to evaluate whether physiological effects of eCreduced stand water-use irrespective of L, which was unaffected by eCin this timeframe. We hypothesized that eCwould reduce tree-canopy transpiration (E), but excess water from reduced Ewould be lost via increased s...
As a partial conclusion, we do argue that indeed, using the T-M formula as the theoretical refere... more As a partial conclusion, we do argue that indeed, using the T-M formula as the theoretical reference is a ‘strong’ assumption which explains that a bivariate solution to elasticity is better that a monovariate one. However, beyond reflecting the “hydrological good sense”, it also reflects the visual impression from the graphs that we present in supplement. Moreover, we believe that the T-M formula’s assumptions are likely to be shared by most hydrologists, and that the T-M formula is both extremely simple and widely-used, which should turn our demonstration acceptable to many of our readers. We thank AV for his suggestion to show graphically that the TM formula implies well defined elasticities at moderate aridity conditions, and we will use this graph in the revised version.
A software to predict the impact of revegetation strategies on the Coarse Sandy Hilly Region of t... more A software to predict the impact of revegetation strategies on the Coarse Sandy Hilly Region of the Loess Plateau of China
Forest plantations can access water from some unconfined aquifers that also contain nitrate at co... more Forest plantations can access water from some unconfined aquifers that also contain nitrate at concentrations that could support hydroponic culture, but the separate effects of such additional water and nitrogen availability on tree growth have not hitherto been quantified. We demonstrate these effects using simulation modelling at two contrasting sites supporting Eucalyptus globulus Labill. or Pinus radiata D.Don plantations. The APSIM Eucalyptus and Pinus models simulated plantation growth within 2% of observed growth where the water table was at 4 m depth for eucalypts (height 28 m, MAI 32 m3 ha−1 year−1) and at 23 m for pines (height 37 m, MAI 20 m3 ha−1 year−1). In simulations without an aquifer, observed growth could only be matched using unrealistically high surface soil nitrogen (N) supply, suggesting this is an unlikely mechanism. Simulated aquifer N concentrations, evapotranspiration, and net N mineralization and leaching (emergent properties of modelling) were similar to ...
mission of the Cooperative Research Centre for Sustainable Rice Production and/or the individual ... more mission of the Cooperative Research Centre for Sustainable Rice Production and/or the individual parties to that joint venture (the " Parties "). Disclaimer The information in this publication is based on knowledge available at the time of writing. The publication is presented in good faith and has been made available by the Cooperative Research Centre for Sustainable Rice Production (Rice CRC) on the basis that recipients of the publication should make their own enquiries and obtain appropriate professional advice before relying on any information or any expression of opinion or prediction contained in this publication. Neither the joint venture known as the Cooperative Research Centre for Sustainable Rice Production (Rice CRC) nor its individual member parties accept liability for any losses, damages or costs resulting from the use of information contained in or omitted from this publication. The views expressed and the conclusions reached in this publication are those o...
The onus for monitoring crop growth from space is its ability to be applied anytime and anywhere,... more The onus for monitoring crop growth from space is its ability to be applied anytime and anywhere, to produce crop yield estimates that are consistent at both the subfield scale for farming management strategies and the country level for national crop yield assessment. Historically, the requirements for satellites to successfully monitor crop growth and yield differed depending on the extent of the area being monitored. Diverging imaging capabilities can be reconciled by blending images from high-temporal-frequency (HTF) and high-spatial-resolution (HSR) sensors to produce images that possess both HTF and HSR characteristics across large areas. We evaluated the relative performance of Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat, and blended imagery for crop yield estimates (2009–2015) using a carbon-turnover yield model deployed across the Australian cropping area. Based on the fraction of missing Landsat observations, we further developed a parsimonious framework ...
We present new global maps of the Köppen-Geiger climate classification at an unprecedented 1-km r... more We present new global maps of the Köppen-Geiger climate classification at an unprecedented 1-km resolution for the present-day (1980-2016) and for projected future conditions (2071-2100) under climate change. The present-day map is derived from an ensemble of four high-resolution, topographically-corrected climatic maps. The future map is derived from an ensemble of 32 climate model projections (scenario RCP8.5), by superimposing the projected climate change anomaly on the baseline high-resolution climatic maps. For both time periods we calculate confidence levels from the ensemble spread, providing valuable indications of the reliability of the classifications. The new maps exhibit a higher classification accuracy and substantially more detail than previous maps, particularly in regions with sharp spatial or elevation gradients. We anticipate the new maps will be useful for numerous applications, including species and vegetation distribution modeling. The new maps including the ass...
Elevated atmospheric COconcentration (eC) might reduce forest water-use, due to decreased transpi... more Elevated atmospheric COconcentration (eC) might reduce forest water-use, due to decreased transpiration, following partial stomatal closure, thus enhancing water-use efficiency and productivity at low water availability. If evapotranspiration (E) is reduced, it may subsequently increase soil water storage (ΔS) or surface runoff (R) and drainage (D), although these could be offset or even reversed by changes in vegetation structure, mainly increased leaf area index (L). To understand the effect of eCin a water-limited ecosystem, we tested whether two years of eC(~40% increase) affected the hydrological partitioning in a mature water-limited Eucalyptus woodland exposed to Free-Air COEnrichment (FACE). This timeframe allowed us to evaluate whether physiological effects of eCreduced stand water-use irrespective of L, which was unaffected by eCin this timeframe. We hypothesized that eCwould reduce tree-canopy transpiration (E), but excess water from reduced Ewould be lost via increased s...
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