Impacts of changing society and climate on nutrient loading to the Baltic Sea.

This paper studies the relative importance of societal drivers and changing climate on anthropogenic nutrient inputs to the Baltic Sea. Shared Socioeconomic Pathways and Representative Concentration Pathways are extended at temporal and spatial scales relevant for the most contributing sectors. Extended socioeconomic and climate scenarios are then used as inputs for spatially and temporally detailed models for population and land use change, and their subsequent impact on nutrient loading is computed.

County, subregional and regional phosphorus data derived from the net anthropogenic nitrogen/phosphorus inputs (NANI/NAPI) toolbox.

The data presented here represent estimates of the phosphorus content of crop production, phosphorus use efficiency (PUE) and agricultural phosphorus inputs associated with it across the contiguous United States. Net Anthropogenic Phosphorus Input (NAPI) estimates and related data are also provided. Data are presented at county, sub-regional and regional scales.

Phosphorus use efficiency and crop production: Patterns of regional variation in the United States, 1987-2012.

Crop N use efficiency (NUE) and P use efficiency (PUE) might be expected to exhibit different patterns across agricultural regions due to their very different environmental dynamics and management strategies. Here, following our previous work on regional patterns of NUE, we review patterns of PUE and related variables, including major inputs of P to US crops over 1987-2012, based on the Farm Resource Regions developed by the Economic Research Service (USDA-ERS). Unlike N, P inputs to cropland only occur in the forms of P fertilizer, which has generally changed little over time relative to N fertilizer, and manure P, which has increased.

Reducing agricultural nutrient surpluses in a large catchment - Links to livestock density.

The separation between crop- and livestock production is an important driver of agricultural nutrient surpluses in many parts of the world. Nutrient surpluses can be symptomatic of poor resource use efficiency and contribute to environmental problems. Thus, it is important not only to identify where surpluses can be reduced, but also the potential policy tools that could facilitate reductions.

County, subregional and regional nitrogen data derived from the Net Anthropogenic Nitrogen Inputs (NANI) toolbox.

[The data presented here represent estimates of the nitrogen content of crop production, nitrogen use efficiency (NUE) and agricultural nitrogen inputs associated with it across the contiguous United States. Net Anthropogenic Nitrogen Input (NANI) estimates and related data are also provided. Data are presented at county, sub-regional and regional scales.

Nitrogen use efficiency and crop production: Patterns of regional variation in the United States, 1987-2012.

National-level summaries of crop production and nutrient use efficiency, important for international comparisons, only partially elucidate agricultural dynamics within a country. Agricultural production and associated environmental impacts in large countries vary significantly because of regional differences in crops, climate, resource use and production practices. Here, we review patterns of regional crop production, nitrogen use efficiency (NUE), and major inputs of nitrogen to US crops over 1987-2012, based on the Farm Resource Regions developed by the Economic Research Service (USDA-ERS).

Influence of rapid rural-urban population migration on riverine nitrogen pollution: perspective from ammonia-nitrogen.

China is undergoing a rapid transition from a rural to an urban society. This societal change is a consequence of a national drive toward economic prosperity. However, accelerated urban development resulting from rapid population migration from rural to urban lands has led to high levels of untreated sewage entering aquatic ecosystems directly.

Evaluating anthropogenic N inputs to diverse lake basins: A case study of three Chinese lakes.

The environmental degradation of lakes in China has become increasingly serious over the last 30 years and eutrophication resulting from enhanced nutrient inputs is considered a top threat. In this study, a quasi-mass balance method, net anthropogenic N inputs (NANI), was introduced to assess the human influence on N input into three typical Chinese lake basins. The resultant NANI exceeded 10,000 kg N km(-2) year(-1) for all three basins, and mineral fertilizers were generally the largest sources.

Enhanced N input to Lake Dianchi Basin from 1980 to 2010: drivers and consequences.

Due to a rapid increase in human population and development of neighborhood economy over the last few decades, nitrogen (N) and other nutrient inputs in Lake Dianchi drainage basin have increased dramatically, changing the lake's trophic classification from oligotrophic to eutrophic. Although human activities are considered as main causes for the degradation of water quality in the lake, a numerical analysis of the share of the effect of different anthropogenic factors is still largely unexplored. We use the net anthropogenic N input (NANI) method to estimate human-induced N inputs to the drainage basin from 1980 to 2010, which covers the period of dramatic socioeconomic and environmental changes.

Reduction of Baltic Sea nutrient inputs and allocation of abatement costs within the Baltic Sea catchment.

The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia.

Estimating net anthropogenic nitrogen inputs to U.S. watersheds: comparison of methodologies.

The net anthropogenic nitrogen input (NANI) approach is a simple quasi-mass-balance that estimates the human-induced nitrogen inputs to a watershed. Across a wide range of watersheds, NANI has been shown to be a good predictor of riverine nitrogen export. In this paper, we review various methodologies proposed for NANI estimation since its first introduction and evaluate alternative calculations suggested by previous literature.

Application of the ReNuMa model in the Sha He river watershed: tools for watershed environmental management.

Models and related analytical methods are critical tools for use in modern watershed management. A modeling approach for quantifying the source apportionment of dissolved nitrogen (DN) and associated tools for examining the sensitivity and uncertainty of the model estimates were assessed for the Sha He River (SHR) watershed in China. The Regional Nutrient Management model (ReNuMa) was used to infer the primary sources of DN in the SHR watershed.

95% of basidiospores fall within 1 m of the cap: a field-and modeling-based study.

Plant establishment patterns suggest that ectomycorrhizal fungal (EMF) inoculant is not found ubiquitously. The role of animal vectors dispersing viable EMF spores is well documented. Here we investigate the role of wind in basidiospore dispersal for six EMF species, Inocybe lacera, Laccaria laccata, Lactarius rufus, Suillus brevipes, Suillus tomentosus and Thelephora americana.

Modeling riverine nutrient transport to the Baltic Sea: a large-scale approach.

We developed for the first time a catchment model simulating simultaneously the nutrient land-sea fluxes from all 105 major watersheds within the Baltic Sea drainage area. A consistent modeling approach to all these major watersheds, i.e.

Assessment of ozone effects on nitrate export from Hubbard Brook Watershed 6.

The impact of the air pollution ozone on soil N dynamics and temporal and spatial patterns of streamflow nitrate flux at the Hubbard Brook Experimental Forest Watershed 6 during the 1964-1994 period was assessed using aggregated (one-cell) and spatially explicit (208-cell) versions of the SImple NItrogen Cycle (SINIC) model. Simulated ozone effects included reductions in stomatal conductance and plant N demand. Model uncertainty was evaluated using Monte Carlo simulations.