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481.
Pesch R Schröder W Schmidt G Genssler L 《Environmental pollution (Barking, Essex : 1987)》2008,155(3):528-536
In order to assess whether nitrogen (N) loads in mosses reflect different land uses, 143 sites in North Rhine-Westphalia, the Weser-Ems Region and the Euro Region Nissa were sampled between 2000 and 2005. The data were analysed statistically with available surface information on land use and forest conditions. N bioaccumulation in mosses in the Weser-Ems Region with high densities of agricultural land use and livestock exceeded the concentrations in the more industrialised Euro Region Nissa. In all three study areas agricultural and livestock spatial densities were found to be positively correlated with N bioaccumulation in mosses. In North Rhine-Westphalia, the N concentrations in mosses was also moderately correlated with N concentrations in leaves and needles of forest trees. The moss method proved useful to assess the spatial patterns of N bioaccumulation due to land use. 相似文献
482.
Ingrid H. Franke-Whittle Alberto Confalonieri Heribert Insam Mirko Schlegelmilch Ina Körner 《Waste management (New York, N.Y.)》2014,34(3):632-641
Anaerobic digestion is a waste treatment method which is of increasing interest worldwide. At the end of the process, a digestate remains, which can gain added value by being composted. A study was conducted in order to investigate microbial community dynamics during the composting process of a mixture of anaerobic digestate (derived from the anaerobic digestion of municipal food waste), green wastes and a screened compost (green waste/kitchen waste compost), using the COMPOCHIP microarray. The composting process showed a typical temperature development, and the highest degradation rates occurred during the first 14 days of composting, as seen from the elevated CO2 content in the exhaust air. With an exception of elevated nitrite and nitrate levels in the day 34 samples, physical–chemical parameters for all compost samples collected during the 63 day process indicated typical composting conditions. The microbial communities changed over the 63 days of composting. According to principal component analysis of the COMPOCHIP microarray results, compost samples from the start of the experiment were found to cluster most closely with the digestate and screened compost samples. The green waste samples were found to group separately. All starting materials investigated were found to yield fewer and lower signals when compared to the samples collected during the composting experiment. 相似文献
483.
In this study, a consistent basin-wise monthly time series of the atmospheric nutrient load to the Baltic Sea during 1850-2006 was compiled. Due to the lack of a long time series (1850-1960) of nutrient deposition to the Baltic Sea, the data set was compiled by combining a time series of deposition data at the Baltic Nest Institute from 1970 to 2006, published historical monitoring data and deposition estimates, as well as recent modeled Representative Concentration Pathways (RCP) emission estimates. The procedure for nitrogen compounds included estimation of the deposition in a few intermediate reference years, linear interpolation between them, and the decomposition of annual deposition into a seasonal deposition pattern. As no reliable monitoring results were found for the atmospheric deposition of phosphorus during the early period of our study, we used published estimates for the temporal and spatial pattern of the phosphorus load. 相似文献
484.
485.
水动力条件对龙须菜N吸收的影响 总被引:8,自引:0,他引:8
通过在室外0.5t的玻璃缸桶内对不同放养密度的龙须菜进行流水和静水的氮吸收比较养殖试验,发现龙须菜可以同时吸收介质中的铵态氮和硝态氮;静水导致水体中的pH值升高,最大的上升了1单位以上;龙须菜的吸收造成介质中营养盐的减少,在试验开始3h后,静水组的高放养密度处理中出现氮吸收抑制现象;采用流水方式,水流速度在(160~175)L·h-1范围,养殖介质的条件相对稳定,藻体所吸收的氮量也较多,流水组的2kg和4kg处理分别比静水相应处理多吸收N为5.80、10.25(16∶00)和7.64、11.59mg(18∶00),分别比静水条件增加24、31和18、27%。 相似文献
486.
487.
Bin Cui Chongjun Zhang Liang Fu Dandan Zhou Mingxin Huo 《Frontiers of Environmental Science & Engineering》2023,17(6):73
488.
Woli KP Hayakawa A Kuramochi K Hatano R 《Environmental monitoring and assessment》2008,137(1-3):251-260
River water quality was evaluated with respect to eutrophication and land use during spring snowmelt and summer base flow
periods in Abashiri (mixed cropland-livestock farming) and Okoppe (grassland-based dairy cattle farming), eastern Hokkaido,
Japan. Water from rivers and tributaries was sampled during snowmelt and summer base flow periods in 2005, and river flow
was measured. Total N (TN), NO3–N, and Si concentrations were determined using standard methods. Total catchment and upland areas for each sampling site
were determined with ArcGIS hydrology modeling software and 1:25,000-scale digital topographic maps. Specific discharge was
significantly higher during snowmelt than during base flow. In both areas, TN concentrations increased, whereas Si concentrations
decreased, with increased specific discharge, and were significantly higher during snowmelt. The Si:TN mole ratio decreased
to below or close to the threshold value for eutrophication (2.7) in one-third of sites during snowmelt. River NO3–N concentrations during base flow were significantly and positively correlated with the proportion of upland fields in the
catchment in both the Abashiri (r = 0.88, P < 0.001) and Okoppe (r = 0.43, P < 0.01) areas. However, the regression slope, defined as the impact factor (IF) of water quality, was much higher in Abashiri
(0.025) than in Okoppe (0.0094). The correlations were also significantly positive during snowmelt in both areas, but IF was
four to eight times higher during snowmelt than during base flow. Higher discharge of N from upland fields and grasslands
during snowmelt and the resulting eutrophication in estuaries suggest that nutrient discharge during snowmelt should be taken
into account when assessing and monitoring the annual loss of nutrients from agricultural fields. 相似文献
489.
Lacerda LD Molisani MM Sena D Maia LP 《Environmental monitoring and assessment》2008,141(1-3):149-164
The Northeastern semi-arid Brazilian region is experiencing rapid social and economic development based on improving water
management and even in areas of low human occupation, anthropogenic emissions of N and P surpass natural emissions in at least
one order of magnitude and these additional loads can alter the water quality of the receiving estuaries. This study estimates,
using an emission factor approach, the annual emissions of N and P from natural processes and anthropogenic sources for estuaries
along the Ceará State, NE Brazil. Emission factors from natural sources are one to two orders of magnitude lower than those
for anthropogenic sources. Among the anthropogenic activities, the aquaculture is responsible for most N emission (0.52 t
km−2 year−1) followed by waste water and husbandry. For P, the largest average emission factors are from husbandry (0.30 t km−2 year−1), waste water and agriculture. 相似文献
490.
研究了大气自动监测系统中标准气、校准气以及零空气的流量大小引起仪器示值误差及时校准曲线质量的影响,提出了重点控制标气流量是减小仪器示值误差的关键,从而解决了低浓度校准点仪器示值偏低、误差大及校准曲线截距大的技术难点,提高了大气自动监测中多点校准质量和监测结果的准确性. 相似文献