How Human Activities Have Modified Nitrogen And Phosphorus Delivery To Global Rivers

2018 ◽  
Author(s):  
Lauriane Vilmin
Keyword(s):  
Human Activities ◽  
Nitrogen And Phosphorus

scholarly journals Spatio-Temporal Dynamics of Riverine Nitrogen and Phosphorus at Different Catchment Scales in Huixian Karst Wetland, Southwest China

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2924
Author(s):  
Linyan Pan ◽  
Junfeng Dai ◽  
Zhiqiang Wu ◽  
Zupeng Wan ◽  
Zhenyu Zhang ◽  
...  
Keyword(s):  
Human Activities ◽  
Temporal Dynamics ◽  
Temporal Variations ◽  
Spatial And Temporal Variations ◽  
Catchment Scale ◽  
Nitrogen And Phosphorus ◽  
Spatial And Temporal Scales ◽  
River Waters ◽  
Hydrological Conditions ◽  
Spatio Temporal

Spatio-temporal dynamics of riverine nitrogen (N) and phosphorus (P) in karst regions are closely linked to hydrological conditions, human activities and karst features in upstream catchments. From October 2017 to September 2019, we undertook 22 sampling campaigns in 11 nested catchments ranging from 21.00 to 373.37 km2 in Huixian karst wetland to quantify forms, concentrations, and fluxes of riverine total nitrogen (TN) and total phosphorus (TP), and to identify spatial and temporal variations of nutrients transfer from upstream to downstream, tributaries (Mudong River and Huixian River) to the main stem (Xiangsi River) in the dry and wet seasons. Considering the hydrological conditions, human activities and karst features within upstream catchments, the following three spatial and temporal variations of riverine nutrients were found over the monitoring period: (1) the dynamics of riverine nitrogen and phosphorus varied seasonally with hydrological conditions; (2) the spatial disparities of riverine nitrogen and phosphorus were induced by different human activities within catchment scales; (3) the dynamics of riverine nitrogen and phosphorus varied similarly at spatial scale restricted by karst features. The findings from this study may improve our understanding of the influence of hydrological conditions, human activities and karst features on nitrogen and phosphorus variations in river waters at different spatial and temporal scales in the Huixian karst wetland basin, and will help managers to protect and restore river water environments in karst basin from a catchment-scale perspective.

scholarly journals Spatiotemporal Variations in Nitrogen and Phosphorus in a Large Man-Made Lake and Their Relationships with Human Activities

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1106
Author(s):  
Ligang Zhou ◽  
Xiangdong Wang ◽  
Xiaoming Zhang ◽  
Yang Zhao ◽  
Panpan Zhu ◽  
...  
Keyword(s):  
Human Activities ◽  
Algal Growth ◽  
Strong Correlations ◽  
Spatiotemporal Variations ◽  
Nitrogen And Phosphorus ◽  
Fishery Policy ◽  
Lake Zone ◽  
Average Water ◽  
Positive Correlations ◽  
Water Eutrophication

Nitrogen and phosphorus excessive enrichment are major causes of water eutrophication, and variations in nutrients enrichment are strongly influenced by human activities. In this study, annual average water quality from 2001 to 2018 was used to explore the spatiotemporal variations in total nitrogen (TN) and total phosphorus (TP) and their relationships with human activities. Spatially, TN and TP concentrations exhibited significant variations across the five sub-lake zones, and their values were relatively higher in the NW lake zone than the other sub-lake zones. Temporally, TN concentration exhibited weak correlations with years in the NW (R2 = 0.37, p < 0.05) and NE (R2 = 0.43, p < 0.05) lake zones and significant and positive correlations with years in the SW (R2 = 0.62, p < 0.05), SE (R2 = 0.79, p < 0.05), and C (R2 = 0.84, p < 0.05) lake zones. TP concentration exhibited decreasing trends in all lake zones except the NW lake zone (R2 = 0.37, p < 0.05), its value shows a relatively low level and is the restrictive factor to algal growth. The trophic state of the Lake Qiandaohu was determined as mesotrophic. Gross domestic product (GDP) and construction land exhibited strong correlations with TN and TP. Moreover, agriculture nonpoint source pollution was the largest contributor to the excessive enrichment of TN and TP, resulting in water eutrophication. In addition, aquaculture was another major source of nutrients starting in 1999. Although the managers of Lake Qiandaohu implemented a protection-oriented fishery policy, good results cannot be easily achieved with a unilateral policy concerning environmental protection. Thus, comprehensive policies may be more effective than unilateral policies.

Local Policy for a Protected Environmental Area Management: The Case of Limiting Motorized Vehicles in Park of Canigou in Pyrenées Orientales

2018 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
Energy Use ◽  
Local Level ◽  
Air Traffic ◽  
Small Scale ◽  
Individual Action ◽  
Local Policy ◽  
Motorized Vehicles ◽  
Local Levels

“We regard the recent science –based consensual reports that climate change is, to a large extend, caused by human activities that emit green houses as tenable, Such activities range from air traffic, with a global reach over industrial belts and urban conglomerations to local small, scale energy use for heating homes and mowing lawns. This means that effective climate strategies inevitably also require action all the way from global to local levels. Since the majority of those activities originate at the local level and involve individual action, however, climate strategies must literally begin at home to hit home.”

Influence of increased nutrient supply on Microcystis aeruginosa at cellular and proteomic levels

2020 ◽  
Vol 85 ◽  
pp. 47-58
Author(s):  
Y Jiang ◽  
Y Liu
Keyword(s):  
Microcystis Aeruginosa ◽  
Regulatory Protein ◽  
Acid Synthesis ◽  
Nutrient Supply ◽  
Nitrogen Supply ◽  
Nitrogen And Phosphorus ◽  
Comprehensive Description ◽  
Amino Acid Synthesis ◽  
High Nutrient ◽  
Proteomic Responses

Various studies have observed that increased nutrient supply promotes the growth of bloom-forming cyanobacteria, but only a limited number of studies have investigated the influence of increased nutrient supply on bloom-forming cyanobacteria at the proteomic level. We investigated the cellular and proteomic responses of Microcystis aeruginosa to elevated nitrogen and phosphorus supply. Increased supply of both nutrients significantly promoted the growth of M. aeruginosa and the synthesis of chlorophyll a, protein, and microcystins. The release of microcystins and the synthesis of polysaccharides negatively correlated with the growth of M. aeruginosa under high nutrient levels. Overexpressed proteins related to photosynthesis, and amino acid synthesis, were responsible for the stimulatory effects of increased nutrient supply in M. aeruginosa. Increased nitrogen supply directly promoted cyanobacterial growth by inducing the overexpression of the cell division regulatory protein FtsZ. NtcA, that regulates gene transcription related to both nitrogen assimilation and microcystin synthesis, was overexpressed under the high nitrogen condition, which consequently induced overexpression of 2 microcystin synthetases (McyC and McyF) and promoted microcystin synthesis. Elevated nitrogen supply induced the overexpression of proteins involved in gas vesicle organization (GvpC and GvpW), which may increase the buoyancy of M. aeruginosa. Increased phosphorus level indirectly affected growth and the synthesis of cellular substances in M. aeruginosa through the mediation of differentially expressed proteins related to carbon and phosphorus metabolism. This study provides a comprehensive description of changes in the proteome of M. aeruginosa in response to an increased supply of 2 key nutrients.

Method application of optimal multi-parameter analysis to assess the distribution of water masses as an example of CTD data of the Barents Sea in summer 2017

2019 ◽  
pp. 38-51
Author(s):  
Valeriy G. Yakubenko ◽  
Anna L. Chultsova
Keyword(s):  
Barents Sea ◽  
Field Measurements ◽  
Structural Similarity ◽  
Water Masses ◽  
Parameter Analysis ◽  
Water Dynamics ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
The Barents Sea ◽  
Expert Assessments

Identification of water masses in areas with complex water dynamics is a complex task, which is usually solved by the method of expert assessments. In this paper, it is proposed to use a formal procedure based on the application of the method of optimal multiparametric analysis (OMP analysis). The data of field measurements obtained in the 68th cruise of the R/V “Academician Mstislav Keldysh” in the summer of 2017 in the Barents Sea on the distribution of temperature, salinity, oxygen, silicates, nitrogen, and phosphorus concentration are used as a data for research. A comparison of the results with data on the distribution of water masses in literature based on expert assessments (Oziel et al., 2017), allows us to conclude about their close structural similarity. Some differences are related to spatial and temporal shifts of measurements. This indicates the feasibility of using the OMP analysis technique in oceanological studies to obtain quantitative data on the spatial distribution of different water masses.

Peculiarities of Energetic, Nitrogen, and Phosphorus Metabolism in Blue-Green Algae under the Influence of Humic Acids

2008 ◽  
Vol 44 (6) ◽  
pp. 74-82
Author(s):  
O. V. Sinyuk ◽  
V. V. Grubinko ◽  
P. D. Klochenko ◽  
T. A. Vasilchuk
Keyword(s):  
Green Algae ◽  
Humic Acids ◽  
Phosphorus Metabolism ◽  
Nitrogen And Phosphorus ◽  
Blue Green Algae

Phytoplankton Production and Decomposition Characteristics in Water Bodies Differing in the Degree of Their Contamination by Inorganic Compounds of Nitrogen and Phosphorus

2019 ◽  
Vol 55 (3) ◽  
pp. 29-43 ◽  
Author(s):  
P. D. Klochenko ◽  
T. F. Shevchenko ◽  
I. N. Nezbrytskaya ◽  
Ye. P. Belous ◽  
Z. N. Gorbunova ◽  
...  
Keyword(s):  
Inorganic Compounds ◽  
Water Bodies ◽  
Phytoplankton Production ◽  
Nitrogen And Phosphorus

Spatiotemporal Changes of Riverbed and Surrounding Environment in Yongding River (Beijing section) in the Past 40 Years

2020 ◽  
Vol 64 (4) ◽  
pp. 40407-1-40407-13 ◽  
Author(s):  
Ran Pang ◽  
He Huang ◽  
Tri Dev Acharya
Keyword(s):  
Economic Development ◽  
Water Conservation ◽  
Human Activities ◽  
Urban Areas ◽  
Water Volume ◽  
Cropland Area ◽  
The Past ◽  
Surrounding Environment ◽  
Spatiotemporal Changes ◽  
Yongding River

Abstract Yongding River is one of the five major river systems in Beijing. It is located to the west of Beijing. It has influenced culture along its basin. The river supports both rural and urban areas. Furthermore, it influences economic development, water conservation, and the natural environment. However, during the past few decades, due to the combined effect of increasing population and economic activities, a series of changes have led to problems such as the reduction in water volume and the exposure of the riverbed. In this study, remote sensing images were used to derive land cover maps and compare spatiotemporal changes during the past 40 years. As a result, the following data were found: forest changed least; cropland area increased to a large extent; bareland area was reduced by a maximum of 63%; surface water area in the study area was lower from 1989 to 1999 because of the excessive use of water in human activities, but it increased by 92% from 2010 to 2018 as awareness about protecting the environment arose; there was a small increase in the built-up area, but this was more planned. These results reveal that water conservancy construction, agroforestry activities, and increasing urbanization have a great impact on the surrounding environment of the Yongding River (Beijing section). This study discusses in detail how the current situation can be attributed to of human activities, policies, economic development, and ecological conservation Furthermore, it suggests improvement by strengthening the governance of the riverbed and the riverside. These results and discussion can be a reference and provide decision support for the management of southwest Beijing or similar river basins in peri-urban areas.

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