42 research outputs found
Effects of watershed land use on nitrogen concentrations and δ15 Nitrogen in groundwater
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 77 (2006): 199-215, doi:10.1007/s10533-005-1036-2.Eutrophication is a major agent of change affecting freshwater, estuarine, and marine
systems. It is largely driven by transportation of nitrogen from natural and anthropogenic
sources. Research is needed to quantify this nitrogen delivery and to link the delivery to
specific land-derived sources. In this study we measured nitrogen concentrations and δ15N
values in seepage water entering three freshwater ponds and six estuaries on Cape Cod,
Massachusetts and assessed how they varied with different types of land use. Nitrate
concentrations and δ15N values in groundwater reflected land use in developed and pristine
watersheds. In particular, watersheds with larger populations delivered larger nitrate loads with
higher δ15N values to receiving waters. The enriched δ15N values confirmed nitrogen loading
model results identifying wastewater contributions from septic tanks as the major N source.
Furthermore, it was apparent that N coastal sources had a relatively larger impact on the N
loads and isotopic signatures than did inland N sources further upstream in the watersheds.
This finding suggests that management priorities could focus on coastal sources as a first
course of action. This would require management constraints on a much smaller population.This work was supported
by funds from the Woods Hole Oceanographic Institution Sea Grant Program, from the
Cooperative Institute for Coastal and Estuarine Environmental Technology, from
Massachusetts Department of Environmental Protection to Applied Science Associates,
Narragansett, RI, as well as from Palmer/McLeod and NOAA National Estuarine Research
Reserve Fellowships to Kevin Kroeger. This work is the result of research sponsored by NOAA
National Sea Grant College Program Office, Department of Commerce, under Grant No.
NA86RG0075, Woods Hole Oceanographic Institution Sea Grant Project No. R/M-40
A 10-year study of background surface ozone concentrations on the island of Gozo in the Central Mediterranean
Informed consent:What do we tell patients about the risk of fatal pulmonary embolism after varicose vein surgery?
Pea (Pisum sativum) and faba beans (Vicia faba) in dairy cow diet: effect on milk production and quality
The use of alternative plant proteins in place
of the soybean meal protein in diets for producing
animals aims to reduce the extra-EU
soybean import and partially substitute the
GMO in the food chain. Among possible alternatives,
the heat-processed legume grains
seem interesting for dairy cow diets. Two consecutive
experiments were carried out to evaluate
flaked pea and faba beans as substitute
for soybean meal in diets for Reggiana breed
dairy cows producing milk for Parmigiano-
Reggiano cheese-making. In both experiments
a C concentrate (110 g/kg soybean meal, no
pea and faba beans) was compared to a PF concentrate
(150 g/kg flaked pea, 100 g/kg flaked
faba beans, no soybean meal). Forages fed to
animals were hay (mixed grass and alfalfa) in
experiment 1 and hay plus mixed grass in
experiment 2. Concentrate intake, milk yield
and milk quality (rennet coagulation traits
included) were similar between feeding
groups. Parameters on the grab faecal samples,
as empirical indicators of digestibility,
had a smaller (P<0.01) amount of residual
concentrate in the PF group compared to the C
group (2.4 vs 3.1 and 2.3 vs 2.8%, respectively
for PF and C in experiment 1 and 2). Some
blood indicators of nitrogen metabolism (protein,
albumin, urea) were similar between the
feeding groups.The inclusion of pea and faba beans, within
the allowed limit of the Parmigiano-Reggiano
Consortium for diet formulation, could represent
a feasible opportunity for a total substitution
of soybean