solution potassium (so-k) and exchangeable k (ex-k) extracted by nh4oac are the major sources of potassium used by plants, but initially non-exchangeable k (nex-k) can also contribute significantly to plant uptake. perennial ryegrass (lolium perenne, cv. roper) was successively planted in ten surface soil samples with different clay mineralogical composition belonging to five soil types to dete...

Increases in the growth rate of plants and microbes in the Mojave Desert in response to predicted increases in precipitation and CO2 due to global climate change may induce nutrient limitations. This study was designed to measure the pool of potentially bioavailable nutrients in soils of the Mojave Desert. Soils were collected from shrub and interspace microsites and then subjected to amendment...

Although elevation of CO2 has been reported to impact soil microbial functions, little information is available on the spatial and temporal variation of this effect. The objective of this study was to determine the microbial response in a northern Colorado shortgrass steppe to a 5-year elevation of atmospheric CO2 as well as the reversibility of the microbial response during a period of several...

Anthropogenic elevated nitrogen (N) deposition has an accelerated terrestrial N cycle, shaping soil carbon dynamics and storage through altering organic mineralization processes. However, it remains unclear how long-term high affects in tropical forests. To address this question, we established a experiment N-rich lowland forest of Southern China with additions such as NH4NO3 0 (Control), 50 (L...

Abstract Targeted use of animal manures as a nitrogen (N) fertilizer is challenging because their poorly predictable N value. An enhanced understanding transformation processes in soil under field conditions necessary to better synchronize availability and crop demand. 15 labeled cattle slurry, produced by feeding heifer with ryegrass hay, was used an on-farm trial on two neighboring fields, cr...

mineralized and inorganic N immobilized into microbial biomass is net N mineralization. Although knowledge Because N is a limiting nutrient in tallgrass prairie and most ecosysof net N mineralization rates is important for assessing tems, changes in N availability or N cycling could control the longterm response of ecosystems to elevated atmospheric CO2. If more potentially plant-available inor...

Trace elements are potentially toxic to human life and the environment. Element toxicity depends on chemical associations in soils. Therefore, determining the chemical form of an element in soils is important to evaluate its mobility and bioavailability. Initial soil development in river floodplains influences soil properties, processes and therefore behavior of trace elements. In this study, t...

Recent evidence suggests that significantly more plant carbon (C) is stored below ground than existing estimates indicate. This study explores the implications for biome C pool sizes and global C fluxes. It predicts a root C pool of at least 268 Pg, 68% larger than previously thought. Although still a low-precision estimate (owing to the uncertainties of biome-scale measurements), a global root...