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The ready availability of industrially fixed reactive nitrogen (Nr) has resulted in a substantial accumulation of Nr in the biosphere. Proper management of Nr is necessary to minimize its negative consequences, while allowing maximization to its positive benefits. An integrated Nr assessment which has not yet been undertaken for India, would be prudent given the future population projections. Basic concepts of an integrated scientific assessment are discussed and two previous integrated Nr assessments (USA and Europe) are compared and contrasted to provide examples from which to draw upon for the design and implementation of an India integrated Nr assessment.

This study focused on individual differences in maternal style and children's developing recall abilities in early memory conversations. Within a longitudinal design, a sample of 56 mother—child dyads was observed while reminiscing, and the children's language skills were assessed when they were 18, 24, and 30 months old. In contrast to mothers classified as “low-eliciting,” mothers in a “high-eliciting” group offered more open-ended elaborative questions, fewer elaborative statements, and more confirmations to their 18-month-olds. Although all mothers increased in their elaborative questioning over time, the stylistic groups that were identified remained distinct. Moreover, children of high-eliciting mothers were providing more memory information, even at the first time point, than were children of low-eliciting mothers, but these differences were magnified at 24 and 30 months. Results of correlational and regression analysis further suggest that children's concurrent language skills, their 24-month recall abilities, and their mothers' reminiscing style when they were 18-months of age each contribute uniquely to the prediction of children's provision of memory elaborations in conversations about the past at 30 months of age.

Mental state language during conversations about the past was assessed in a shortterm longitudinal study. Twenty-one mother-child dyads discussed several previously experienced events when the children were 30 and 42 months old. Over time, children's mental term use--although quite low--did increase, and both mothers and children talked more about the process of remembering in their references to mental states. Neither mothers' nor children's mental term use correlated with measures of the children's verbal abilities. Only the children's and not mothers' early use of mental terms uniquely predicted children's later mental term use. Associations were also found between children's mental term use during reminiscing and their deliberate remembering of objects in a strategic memory task performed at 42 months.

Response style, specifically the tendency to use response categories that are distant from the midpoint of a Likert-type scale, has been linked to culture and to the personal meaningfulness of the item. In this study, 58 Spanish-English bilinguals completed two gender role attitudes scales—the Attitudes Toward Women Scale (AWS) and the Historic-Sociocultural Premises Scale (HSCP)—with items randomly assigned to be presented in English or Spanish. The HSCP was rated as more meaningful, and participants used more extreme categories in Spanish. Participants rated items on the AWS as more meaningful and used more extreme categories when items were presented in their first language; meaningfulness did not completely account for the latter effect. The results suggest that both language and meaningfulness affect response style. Response style is important not only as a confounding variable in crosscultural research but as an indicator of personal meaning and other culturally related phenomena such as language.

When considering how swine production will be affected by climate, perhaps the best place to start is to consider the present day vulnerabilities of the industry. The swine industry, like most of the meat production industry, is based on intensive production with trends suggesting future increases in intensification. This industry model depends on cheap grain, cheap energy, and manageable disease control. Some expect that future temperature, and precipitation frequency and intensity may have direct impacts on nonintensive swine production but are not likely to directly affect intensive production because the barn environment is controlled. However, there could be an increase in the frequency, intensity, and severity of both severe storms (e.g., hurricanes, tornadoes, etc.), which might increase the upset of large open-air lagoon treatment systems and flooding of barns. This could lead to increased pressure on intensive operations to modify current manure treatment systems. Climate effects could, thus, have negative impacts on feed grain production, which will affect its availability and price. Climate influences would also have indirect impacts on energy costs as demands for renewable energy increase, which could also put upward pressure on feed grain prices as bioenergy production competes for feed grains. The climate impacts on growth, reproductive success, and distribution of diseases may impact the ability to manage disease. This concern may be heightened in intensive production relative to nonintensive systems owing to the density of animals. Future greenhouse gas mitigation efforts may produce costs or revenue opportunities for the swine industry. Last, the role of reactive nitrogen (Nr) in climate and other intertwined issues could be very important. Swine producers will need to adapt to all these changes to maintain production levels.

Enhanced phytoplankton production and algal blooms, symptoms of eutrophication, are frequently caused by elevated nutrient loading, usually a s nitrogen, to coastal waters. This nitrogen is derived primarily from anthropogenic sources (urban, industrial, and agricultural) but is delivered to coastal waters through meteorological and hydrological means. We utilized a 4 yr monthly data set to investigate the effect of these upstream physical forces upon primary productivity of the Neuse River Estuary (North Carolina. USA), a large temperate coastal plain estuary Our results indicate that the magnitude of estuarine primary production and the periodicity of algal blooms can be directly related to variations in upper watershed rainfall and its subsequent regulation of downstream nver flow Future changes in preclpitatlon patterns for coastal regions may thus lead to substantlal alterations in coastal primary productiv~ty rates and patterns. Biological productivity in estuarine waters is influenced by a host of factors including latitude, season, irradiance, temperature, flow, nutrient loading and recycling, grazing, and watershed geomorphology and development (Mann 1982, Nixon 1986, Day et al. 1989). Upstream river flow has been recognized as an important influence on the primary productivity, salinity, nutrient loading, light attenuation, dissolved oxygen, and stratification of estuarine waters (Cooper & Copeland 1973, Jaworski 1981, Sellner 1987, Randall & Day 1987, Malone et al. 1988, Christian et al. 1991, Jordan et al. 1991, Rudek et al. 1991, Gallegos et al. 1992). Factors controlling river flow should, therefore, be expected to affect estuarine primary productivity. Present addresses: 'Department of Biological Sciences, University of North Carolina at Wilmington, Wilmington, North Carolina 28403, USA ' 'USGS MS 469,345 Middlefield Rd. Men10 Park, California 94025, USA ' 'Department of Horticulture. 1575 Linden Dr., University of Wisconsin, Madison. Wisconsin 53106. USA The Neuse River Estuary, North Carolina, USA, typifies coastal plain estuaries with its large drainage basin (16000 km2) , relatively shal1o.w water, and elevated nutrient loading from urban, industrial, and agricultural sources (Stanley 1988, Christian et al. 1991). Bioassays have indicated that primary productivity is predominantly nitrogen-limited in this system (Rudek et al. 1991). The phytoplankton conlmunity is dominated by centric diatoms, dinoflagellates, and cryptomonads, with community structure influenced by salinity; increased freshwater inputs favor cryptomonads, whereas diatoms tend to dominate under more saline conditions, and dinoflagellates are usually subdominant except for periodic blooms (Mallin et al. 1991). Previous research indicated that during 1988-1989 primary productivity was strongly correlated with surface nitrate concentrations and negatively correlated with salinity (Mallin et al. 1991). Also, periods of increased river flow were associated with increases in nitrate and decreases in salinity (Rudek et al. 1991). Based on this information, our objective in the present research was to examine how the interplay of physical and chemical variables affected estuarine primary productivity from a n ecosystem perspective. Accordingly, we utilized a long-term data set to investigate the extent to which river flow and its primary driving force, watershed rainfall, influenced the primary productivity of this large temperate estuary. Materials and methods. We sampled for phytoplankton productivity, taxa composition and abundance, chlorophyll a, nutrients, and physical factors at Channel Marker 6, a mesohaline station located about 10 km from the mouth of the estuary where it joins Pamlico Sound (Fig. 1). Samples were collected approximately monthly over a 4 yr perlod (1988 to 1992). Primary productivity was assessed by the 14C 0 Inter-Research 1993 200 Mar. Ecol. Prog. Ser. 93: 199-203, 1993

Phytoplankton community composition, productivity and biomass characteristics of the mesohaline lower Neuse River estuary were assessed monthly from May 1988 to February 1990. An incubation method which considered water-column mixing and variable light exposure was used to determine phytoplankton primary productivity. The summer productivity peaks in this shallow estuary were stimulated by increases in irradiance and temperature. However, dissolved inorganic nitrogen loading was the major factor controlling ultimate yearly production. Dynamic, unpredictable rainfall events determined magnitudes of seasonal production pulses through nitrogen loading, and helped determine phytoplankton species composition. Dinoflagellates occasionally bloomed but were otherwise present in moderate numbers; rainfall events produced large pulses of cryptomonads, and dry seasons and subsequent higher salinity led to dominance by small centric diatoms. Daily production was strongly correlated (r = 0·82) with nitrate concentration and inversely correlated (r = −0·73) with salinity, while nitrate and salinity were inversely correlated (r = −0·71), emphasizing the importance of freshwater input as a nutrient-loading source to the lower estuary. During 1989 mean daily areal phytoplankton production was 938 mgC m−2, mean chlorophyll a was 11·8 mg m−3, and mean phytoplankton density was 1·56 × 103 cells ml−1. Estimated 1989 annual areal phytoplankton production for the lower estuary was 343 gC m−2.

Nutrient limitation of phytoplankton production was assessed monthly from 1987 through 1990 in the lower Neuse River Estuary, North Carolina, USA, a well-mixed, mesotrophic system. Nutrient addition bioassays indicated that the lower estuary experienced a general state of nitrogen limitation, with especially pronounced limitation during summer months, a period of high phytoplankton productivity. Bioassays conducted during spring months showed significantly greater stimulation of algal productivity with the addition of nitrogen and phosphorus than that found with nitrogen addition alone. This CO-stimulation occurred during periods when surface-water dissolved inorganic nitrogen : dissolved inorganic phosphorus ratios were elevated above typical values of < 5. Seasonal patterns in ambient nutrient concentrations revealed nitrogen maxima associated with spring, fall, and winter runoff events, with summer minima Hydrologically driven nitrogen loading exerted a strong, yearround influence on primary production and nutrient limitation characteristics. High-flow events acted to oversaturate the upper estuarine nutrient filtering capacity, resulting in increased delivery of nitrogen to the lower estuarine environment. The phytoplankton community responded to increased flow and concomitant nutrient loadings by increasing production and b~omass levels, often very rapidly. In this regard, hydrologic factors influencing nitrogen loading (terrigenous runoff, point source inputs, and wet and dry atmospheric deposition) are key determinants of the trophic state of this estuary.

Recent evaluations of estuarine and coastal nutrient budgets implicate atmospheric deposition as a potentially significant (20 to 30%) source of biologically available nitrogen. We examined the potential growth stimulating impact of atmospheric nitrogen loading (ANL), as local rainfall, in representative shallow, nitrogen limited North Carolina mesohaline estuarine and euhaline coastal Atlantic Ocean habitats. From July 1988 to December 1989, using in situ bioassays, we examined natural phytoplankton growth responses, as14CO2 assimilation and chlorophylla production, to rain additions over a range of dilutions mimicking actual input levels. Rainfall at naturally occurring dilutions (0.5 to 5%) stimulated both14CO2 assimilation and chlorophylla production, in most cases in a highly significant manner. Parallel nutrient enrichments consistently pointed to nitrogen as the growth stimulating nutrient source. Generally, more acidic rainfall led to greater magnitudes of growth stimulation, especially at lower dilutions. Nutrient analyses of local rainfall from May 1988 to January 1990 indicated an inverse relationship between pH and NO 3 - content. There have been growing concerns regarding increasing coastal and estuarine eutrophication, including ecologically and economically devastating phytoplankton blooms bordering urban and industrial regions of North America, Europe, Japan, and Korea. It appears timely, if not essential, to consider atmospheric nutrient loading in the formulation and implementation of nutrient management strategies aimed at mitigating coastal eutrophication.