The damming of rivers represents one of the most far-reaching human modifications of the flows of water and associated matter from land to sea. Dam reservoirs are hotspots of sediment accumulation, primary productivity (P) and carbon mineralization (R) along the river continuum. Here we show that for the period 1970-2030, global carbon mineralization in reservoirs exceeds carbon fixation (P<R);...

Soil organic matter (SOM) is essential for sustaining soil health and crop productivity. However, changes in SOM stocks in response to agronomic practices are slow and show years later when it is too late for adjustments in management. Identifying early indicators of SOM dynamics will allow early management decisions and quick remedial action. The objectives of this study were to evaluate long-...

Mixed tree–grass vegetation is important globally at ecotones between grasslands and forests. To address uncertainties vis-à-vis productivity and nitrogen (N) cycling in such systems we studied 20 mature oak savanna stands, ranging from 90% woody dominated to 80% herbaceous dominated, growing on comparable soils in a 32-yr-old fire frequency experiment in Minnesota, USA. Fire frequencies ranged...

[1] Understanding factors that control methane exchange between soils and the atmosphere remains one of the highest priorities for climate change research. Here we use a novel isotope-based technique to investigate the relative importance of three mechanisms for explaining landscape-scale variations in soil methane emissions: (1) consumption of methane by methanotrophic bacteria, (2) quantity o...

field experiments were conducted at the rice research institute (mazandaran province) using randomized complete block designs in two fields of different levels of organic carbon (low and medium) during two cropping years. the treatments were repeated in three replicates and while seven nitrogen levels (urea-n input) 0, 23, 46, 69, 92, 115 and 138 kg n per ha employed. results indicated that opt...

Remarkable numbers of microbial cells have been observed in global shallow to deep subseafloor sediments. Accumulating evidence indicates that deep and ancient sediments harbor living microbial life, where the flux of nutrients and energy are extremely low. However, their physiology and energy requirements remain largely unknown. We used stable isotope tracer incubation and nanometer-scale seco...

At a spatially heterogeneous mixed-conifer forest in the central California Sierras, we quantified total carbon (C) and nitrogen (N), inorganic N, and net N mineralization in organic (O) and surface (0–15 cm) mineral soils, and in situ fluxes of inorganic N and ortho-phosphate using resin lysimeters under three patch types: closed canopy conifer, sparsely vegetated open canopy, and Ceanothus co...

Instrumental analysis of vermicompost with the help of modern technologies provides essential information on its maturity, before it can be used for agricultural application. Nowadays, vermicompost is considered as a promising organic alternative to chemical fertilizers in agriculture and horticulture. The objectives of this review are to summarize the sophisticated instrumental techniques such...