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The nitrogen budget of a salt marsh ecosystem
  • The nitrogen budget of a salt marsh ecosystem
  • Salt marshes reduces oxidised nitrogenous compounds to ammonium and particulate nitrogen and export these reduced forms to coastal waters. The internal demands exceed the net imputs of nitrogen by rain, groundwater flow and fixation, suggesting very
  • active uptake conversion, release and recycling of nitrogen within a marsh ecosystem. Nitrogen losses are mainly through tidal exchanges and denitrification, and these two outputs balance the gains. The chemical exchanges among uplands, marshes
Mineral nitrogen reserve in the soils of Belgium and the northern part of France during the winter of 1990
  • Mineral nitrogen reserve in the soils of Belgium and the northern part of France during the winter of 1990
  • Agropedology ; Belgium ; France ; Nitrogen ; Northern France ; Soil ; Soil properties ; Soil science
  • Since the introduction of the N-INDEX advice system in Belgium and in the northern part of France, the number of mineral nitrogen analyses of the soil is increasing. Also in the Netherlands where one has the N-MINERAAL advice system, the mineral
  • nitrogen analyses increased since 1975. The availability of the many soil analysis data makes it possible to give a review of the mineral nitrogen in the soil as a function of many factors i.e. the previous crop, the soil type, the organic fertilizer
Dynamics of nitrogen fixation in a meadow biogeocenosis
  • Dynamics of nitrogen fixation in a meadow biogeocenosis
The distribution of sulphur and carbon-nitrogen-sulphur relationships in some North Queensland soils
  • The distribution of sulphur and carbon-nitrogen-sulphur relationships in some North Queensland soils
Stickstoff als Okofaktor naturnaher Berg-Fichtenwälder. (Nitrogen as an ecofactor in close-to-nature mountainous spruce forests)
  • Stickstoff als Okofaktor naturnaher Berg-Fichtenwälder. (Nitrogen as an ecofactor in close-to-nature mountainous spruce forests)
  • Differential patterns of nitrogen content of F+H-layer in 11 forms of mountainous spruce forest in the area of the Harz moutains and the Sudetes are analysed. Total nitrogen, hydrolysable nitrogen and lumb amino acid content of the organic soil
  • substance are considered in their mutual relations as well as in relation to the vegetation structure. The proportion of nitrogenous compounds resistent to hydrolysis is small compared to other forms of humus and vegetation complexes. The individual forms
  • of mountainous spruce forests do not differ at all or only slightly with regard to the relative proportions of the main kinds of nitrogen-acid-hydrolysable, water-soluble and residual nitrogen-while the absolute forms show a manyfold differential pattern
An assessment of planting flexibility options to reduce the excessive application of nitrogen fertilizer in the United States of America
  • An assessment of planting flexibility options to reduce the excessive application of nitrogen fertilizer in the United States of America
  • Crop ; Crop yield ; Cropping ; Cultivated land;Cultivated surface ; Farm income ; Farming;Agriculture ; Fertilizer ; Nitrogen ; Optimization ; United States ; Water pollution
  • The analysis is directed at estimating the marginal value of a base acre, the nitrogen rate of fertilizer use, the corn yield, and the excess nitrogen rate under alternative policy options designed to encourage planting flexibility in response
Spatial distributions of organic carbon and nitrogen and their isotopic compositions in sediments of the Changjiang Estuary and its adjacent sea area
  • Spatial distributions of organic carbon and nitrogen and their isotopic compositions in sediments of the Changjiang Estuary and its adjacent sea area
  • Carbon ; China ; Coastal sedimentation ; Estuary ; Geochemistry ; Isotope analysis ; Jiangsu ; Nitrogen ; Organic materials ; Spatial distribution
  • The spatial distribution patterns of total organic carbon and total nitrogen show significant correlations with currents of the East China Sea Shelf. The purposes of this paper are to analyze characteristics of stable carbon and nitrogen isotopes
The effect of natural weed buffers on soil and nitrogen losses in Japan
  • The effect of natural weed buffers on soil and nitrogen losses in Japan
  • Cultivated land ; Geochemistry ; Glacier mass balance ; Honshu ; Japan ; Nitrogen ; Precipitation ; Soil ; Soil conservation ; Soil erosion ; Soil water
  • In Japan, heavy rains from June to October cause severe erosion in the agricultural fields. This paper describes the mass balances of the water, soil and nitrogen components in a plot of 159 m2 dominated by weeds. This paper also evaluates
  • the ability of natural weed buffers to reduce soil and nitrogen losses.
A study on the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region, China
  • A study on the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region, China
  • Agricultural production ; Agro-ecology ; Agropedology ; China ; Environmental degradation ; Fertilizer ; Geochemistry ; Geographical information system ; Nitrogen ; North-Eastern China ; Spatial distribution
  • The AA. made use of the farmland nitrogen balance model to assess the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region in 2008 with the assistance of GIS. Their results indicated that: 1) Farmland in this region has
  • a nitrogen surplus totaling 5.0822 million tons, or an average of 288.54 kg/ha. 2) In the Bohai Rim region, farmland nitrogen input and farmland nitrogen budget both show a spatial differentiation. Major grain-producing areas have a higher nitrogen input than
  • that of the grazing-farming areas. Chemical fertilizer is the predominant source of nitrogen input to farmland. Therefore, this study provides scientific evidences for rationalizing the use of chemical fertilizer and managing agricultural operation on the regional
A brief introduction to recent applications of several sediment-analysis techniques in palaeolimnological studies - dry bulk density and water content, mineral magnetism, carbonate content, and content of total organic carbon, nitrogen content and carbon/nitrogen ratio
  • A brief introduction to recent applications of several sediment-analysis techniques in palaeolimnological studies - dry bulk density and water content, mineral magnetism, carbonate content, and content of total organic carbon, nitrogen content
  • and carbon/nitrogen ratio
  • Determination of dry bulk density and water content, mineral magnetism, carbonate content, total organic carbon (TOC) content, nitrogen content (N%) and carbon/nitrogen (C/N) ratio are among those techniques which have been widely applied
The load of organic carbon, nitrogen and phosphorus from two large drainage basins (River Kitka and River Oulanka) in NE Finland
  • The load of organic carbon, nitrogen and phosphorus from two large drainage basins (River Kitka and River Oulanka) in NE Finland
  • Carbon ; Cold area ; Finland ; Hydrochemistry ; Hydrology ; Leaching ; Nitrogen ; Nutrient ; Solution load ; Watershed
  • The aim of this paper is to quantify the load of organic carbon, nitrogen and phosphorus from 2 large catchment areas, the River Kitka and the River Oulanka, and the transport of the nutrients into Lake Paanajärvi, a deep oligotrophic lake in NW
Effects of nitrogen input and nitrogen surplus taxes in Dutch agriculture
  • Effects of nitrogen input and nitrogen surplus taxes in Dutch agriculture
Nitrogen fixation in some terrestrial environments in Nitrogen fixation. Volume 1: Ecology.
  • Nitrogen fixation in some terrestrial environments in Nitrogen fixation. Volume 1: Ecology.
Nitrogen fixation in waters in Nitrogen fixation. Volume 1: Ecology.
  • Nitrogen fixation in waters in Nitrogen fixation. Volume 1: Ecology.
Soil nitrogen transformations associated with small patterned-ground features along a North American Arctic transect
  • Soil nitrogen transformations associated with small patterned-ground features along a North American Arctic transect
  • Alaska ; Arctic Region ; Biogeochemical cycle ; Canada ; Cold area ; Geochemistry ; Latitude ; Nitrogen ; Patterned ground ; Spatial analysis ; Tundra
  • Small patterned-ground features (PGFs) in the Arctic have unique soil properties that vary with latitude and may greatly affect tundra biogeochemistry. Because nitrogen availability can strongly limit arctic vegetation growth, the AA. examined how
  • soil nitrogen transformations differ between PGFs and the surrounding inter-PGF tundra along an arctic latitudinal gradient. The 8 study sites are located from the Alaskan Low Arctic to the Canadian High Arctic. The soils were incubated for 21 days at 9
  • °c and 15°c and analysed for changes in total inorganic nitrogen, nitrate and extractable organic nitrogen (EON). The results show that spatial heterogeneity at several scales can influence soil nitrogen dynamics, and is therefore an important
Reducing nitrogen and phosphorus losses from arable slope land with contour hedgerows and perennial alfalfa mulching in Three Gorges Area, China
  • Reducing nitrogen and phosphorus losses from arable slope land with contour hedgerows and perennial alfalfa mulching in Three Gorges Area, China
  • Agricultural practice ; Agropedology ; China ; Comparative study ; Erosion control ; Experiment plot ; Geochemistry ; Hubei ; Nitrogen ; Phosphorus ; Precipitation ; Rill wash ; Sediment budget ; Soil erosion ; Water erosion
  • The loss of nitrogen and phosphorus from arable slope land threatens the aquatic environment in the Three Gorges Area, China, and the protection of these slopes will play an important role in regional agricultural development. During the last 10
  • years, a long-term comparison of ecological methods to reduce losses of nitrogen and phosphorus has been carried out with 5 treatments. Rainfall (P), runoff, rainfall intensities (I10, I20, I30, I60), sediment yield, and nitrogen and phosphorus losses
  • with toon contour hedgerows could effectively reduce runoff, sediment yield and losses of nitrogen and phosphorus from arable slope land. The reductions of sediment yield and losses of nitrogen and phosphorus increased with the increase of rainfall
Exploring the relationship between leaf nitrogen content, biomass and the near-infrared/red reflectance ratio
  • Exploring the relationship between leaf nitrogen content, biomass and the near-infrared/red reflectance ratio
Oblique view reflectance for assessing nitrogen status of incomplete canopies
  • Oblique view reflectance for assessing nitrogen status of incomplete canopies
Phosphorus and nitrogen levels of Spartina foliosa and Salicornia virginica in disturbed and undisturbed marsh in Coasts under stress.
  • Phosphorus and nitrogen levels of Spartina foliosa and Salicornia virginica in disturbed and undisturbed marsh in Coasts under stress.
Paddy fields in Nitrogen fixation. Volume 1: Ecology.
  • Paddy fields in Nitrogen fixation. Volume 1: Ecology.