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Investigation the effect of the main land-based pollutants in Xiangshan Bay

Wang Xueping, Zhu Huibin, Geng Yue, Ding Kexuan, Ye Linan

Ecological Chemistry and Engineering. S

2022

Vol. 29, nr 1

27--38

This paper analyses and discusses the monthly and annual changes of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) concentrations from main sewage discharge ports in Xiangshan Bay. Using monitoring data obtained from 2010 to 2019, it systematically examines the monthly variation characteristics of the sewage discharge ports and the interannual changes in the fluxes of major pollutants into the sea. The concentrations of COD, TN, and TP, which were relatively high in November and January-March, generally declined. The annual and monthly changes fluctuated, but the flux into the sea generally decreased. The ecological environment of the nearby sea area is adversely affected, chiefly by land-based pollutants. During the five-year period, COD mainly came from soil erosion and domestic pollution, while TN and TP mainly came from agricultural activities and soil erosion. Hence, it is both necessary and urgent to improve the management of the sewage outfalls from land sources into the sea.

The Influence of Disturbance Type on Precipitation - Use Efficiency at Functional Group and Species Scales in an Arid Habitat

Busso C. A., Montenegro O. A., Torres Y. A., Giorgetti H. D., Rodriguez G. D.

Polish Journal of Ecology

2016

Vol. 64, nr 2

143--164

We used long-term datasets (1984–1992) to contrast precipitation-use efficiency estimates between various disturbance kinds at a functional group and/or a species scale. Effects of varying amounts of precipitation and plant cover on PUE were also examined. Field studies were conducted at northeastern, arid Patagonia, Argentina (40°39′49″S, 62°53′6.4″W). Within each management kind, biomass was sampled in 0.5 × 0.5m permanent plots (n = 30) over 9 years after defoliation at 5 cm stubble at the end of each growing season, and it was separated into species. Biomass sampling allowed determination of annual net primary production. Thereafter, species were grouped into each of three functional groups. Precipitation-use efficiency (PUE) was calculated as the total dry matter produced per unit surface area on any given year divided by the total rainfall in that year. Plant cover on 20 out of those 30 plots was determined to study the relationship between plant cover and PUE. The contribution of cool-season perennial grasses to total PUE was higher (P <0.05) than that found for the other two functional groups in all management kinds and years. PUE was similar (P> 0.05) in wet than dry years, and it was greater (P <0.05) or similar (P> 0.05), but not lower, on the more than less competitive perennial grass species in all management kinds. The relationship between plant cover and PUE was positive, linear (P <0.0000) and management-kind dependent.