Nutrient legacies in anthropogenic landscapes, accumulated over decades of fertilizer application, lead to time lags between implementation of conservation measures and improvements in water quality. Quantification of such time lags has remained difficult, however, due to an incomplete understanding of controls on nutrient depletion trajectories after changes in land-use or management practices. In this study, we have developed a parsimonious watershed model for quantifying catchment-scale time lags based on both soil nutrient accumulations (biogeochemical legacy) and groundwater travel time distributions (hydrologic legacy). The model accurately predicted the time lags observed in an Iowa watershed that had undergone a 41% conversion of area from row crop to native prairie. We explored the time scales of change for stream nutrient concentrations as a function of both natural and anthropogenic controls, from topography to spatial patterns of land-use change. Our results demonstrate that the existence of biogeochemical nutrient legacies increases time lags beyond those due to hydrologic legacy alone. In addition, we show that the maximum concentration reduction benefits vary according to the spatial pattern of intervention, with preferential conversion of land parcels having the shortest catchment-scale travel times providing proportionally greater concentration reductions as well as faster response times. In contrast, a random pattern of conversion results in a 1:1 relationship between percent land conversion and percent concentration reduction, irrespective of denitrification rates within the landscape. Our modeling framework allows for the quantification of tradeoffs between costs associated with implementation of conservation measures and the time needed to see the desired concentration reductions, making it of great value to decision makers regarding optimal implementation of watershed conservation measures.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4436186 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0125971 | PLOS |
Publication Analysis
Top Keywords
Similar Publications
Circadian rhythm of heart rate and activity: A cross-sectional study.
Chronobiol Int
January 2025
Google LLC, San Francisco, California, USA.
Circadian rhythms are governed by a biological clock, and are known to occur in a variety of physiological processes. We report results on the circadian rhythm of heart rate observed using a wrist-worn wearable device (Fitbit), consisting of over 17,000 individuals over the course of 30 days. We obtain an underlying heart rate circadian rhythm from the time series heart rate by modeling the circadian rhythm as a sum over the first two Fourier harmonics.
View Article and Find Full Text PDFComparison of Oncology Drug Lag in Japan and South Korea Based on the Interval between the U.S. Approval and the Local Approval.
Biol Pharm Bull
January 2025
Department of Clinical Medicine (Pharmaceutical Medicine), Graduate School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
Drug lag is a serious issue for patients with life-threatening diseases such as cancer. Japan and Korea have been facing a large drug lag, despite having a large market and a good clinical trial environment. We analyzed drug lags for anticancer drugs between these countries, using the information on 82 anticancer drugs approved in the United States between 2017 and 2022.
View Article and Find Full Text PDFAssociation between behavioral jet lag with subjective and objective circadian rhythm among Chinese young adults.
Soc Sci Med
January 2025
Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, Hefei, China; MOE Key Laboratory of Population Health Across Life Cycle, Hefei, China; Center for Big Data and Population Health of IHM, Anhui Medical University, Hefei, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Hefei, China; Anhui Provincial Key Laboratory of Environment and Population Health Across the Life Course, Anhui Medical University, Hefei, China. Electronic address:
Background: Behavioral jet lags (social and eating jet lag), the difference in sleep and eating time between weekdays and weekends, are ubiquitous in modern society. However, evidence on the effects of behavioral jet lags on circadian rhythm is limited.
Methods: Social jet lag was assessed using wrist-worn accelerometers.
Boreal forests are heading for an open state.
Proc Natl Acad Sci U S A
January 2025
Environmental Sciences Department, Wageningen University & Research, Wageningen 6708 PB, The Netherlands.
The boreal forest biome is warming four times faster than the global average. Changes so far are moderate, but time lags in responses may transiently maintain forest states which are no longer supported by current environmental conditions. Here, we explore whether tree cover dynamics hint at the state to which the biome may be shifting.
View Article and Find Full Text PDFA multivariate soil temperature interval forecasting method for precision regulation of plant growth environment.
Front Plant Sci
December 2024
College of Big Data and Internet, Shenzhen Technology University, Shenzhen, China.
Foliage plants have strict requirements for their growing environment, and timely and accurate soil temperature forecasts are crucial for their growth and health. Soil temperature exhibits by its non-linear variations, time lags, and coupling with multiple variables, making precise short-term multi-step forecasts challenging. To address this issue, this study proposes a multivariate forecasting method suitable for soil temperature forecasting.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!