Crop water use (ET) of third year Chico walnuts under low volume sprinkler irrigation in both high and conventional density plantings were measured at the Kearney Agricultural Center in 1984. Crop yield was also evaluated. Additionally, the yield response to varying levels of pruning of selected high density guard row trees was assessed. On a per tree basis, high density tree peak ET (25 gal/tr...

The numerical method for estimating soil moisture transport coefficients in land surface models (LSMs) is evaluated through comparison to a weighted-average method based on successive steady states [Warrick, 1991] and a proposed new scheme [Dong and Wang, 1997]. The focus is on situations with large gradients of soil moisture. The reference cases used to evaluate the performance of the various ...

Maize is the New World’s preeminent grain crop and it provided the economic basis for human culture in many regions within the Americas. To flourish, maize needs water, sunlight (heat), and nutrients (e.g., nitrogen). In this paper, climate and soil chemistry data are used to evaluate the potential for dryland (rainon-field) agriculture in the semiarid southeastern Colorado Plateau and Rio Gran...

Stable isotope techniques can be used to investigate evapotranspiration and its partitioning into evaporation transpiration. However, verification is often difficult due missing information about actual evapotranspiration. Therefore, in this study a methodology tested for laboratory conditions was modified field applications. Evapotranspiration, which determined by weighing lysimeters, were com...

Estimating the magnitude of the different fluxes in the hydrological cycle is essential if we are to predict the impacts of climate change. However, climate change is acting on a dynamic three dimensional globe where change in one region may produce impacts in another. This creates a need to expand the current climate change studies to encompass the entire globe. Evaporation is a key component ...

Reducing water losses in agriculture needs a solid understanding of when evaporation (E) occur and how much is used through crop transpiration (T). Partitioning ecosystem T however challenging, even more so it comes to short-statured crops, where many standard methods lead inaccurate measurements. In this study, we combined biometeorological measurements with Soil-Plant-Atmosphere Crop (SPA-Cro...

Abstract Changing pathways of soil moisture loss, either directly from (evaporation) or indirectly through vegetation (transpiration), are an indicator ecosystem and land hydrological cycle responses to the changing climate. Based on ratio transpiration evaporation, this paper investigates loss pathway changes across China using five reanalysis-type datasets for past Coupled Model Intercomparis...

Higher global temperatures and increased levels of disturbance are contributing to greater tree mortality in many forest ecosystems. These same drivers can also limit forest regeneration, leading to vegetation type conversion. For the Sierra Nevada of California, little is known about how type conversion may affect streamflow, a critical source of water supply for urban, agriculture and environ...