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Kari-Matti Vuori Ilona Joensuu Jyrki Latvala Eero Jutila Anssi Ahvonen 《水产资源保护:海洋与淡水生态系统》1998,8(6):745-759
1. Forest drainage, including mainly ditching of waterlogged peatlands in order to increase wood growth, has caused substantial changes in the hydrology and water quality of Finnish streams. However, knowledge on the ecological impact of these changes is poor. This paper studies the potential impact of forest drainage, catchment characteristics and habitat factors on the water quality and benthic macroinvertebrates in headwater streams of the River Isojoki, western Finland. An intensive programme of water sampling was carried out at nine study sites, while zoobenthic samples covered a total of 18 streams. 2. According to multivariate regression models concentrations of aluminium and suspended solids in stream water at nine study sites increased significantly with increasing forest drainage of the catchment area. Further, drainage intensity contributed significantly to the decrease in minimum values of alkalinity. 3. In a Canonical Correspondence Analysis, the variation in macroinvertebrate species distribution and abundance was largely explained by drainage intensity, moss coverage and the concentrations of aluminium and iron in stream water. A significant positive correlation was established between the species richness of benthic macroinvertebrates and the proportional cover of vegetation on the stream bed, whereas a significant negative correlation was found between species richness and sand cover. 4. The results suggest that drainage has significantly contributed to the deterioration of water quality and habitat structure, and impoverishment of benthic communities in the headwater streams of the River Isojoki. In order to protect the ecological integrity of such boreal headwater streams, more effective protection schemes in forestry practices and rehabilitation of the adversely affected streams and their catchment areas are needed. © 1998 John Wiley & Sons, Ltd. 相似文献
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Rosendahl Sarah Anturaniemi Johanna Vuori Kristiina A. Moore Robin Hemida Manal Hielm-Björkman Anna 《Veterinary research communications》2022,46(1):261-275
Veterinary Research Communications - Obtaining correct amounts of essential elements, and avoiding toxic metals are key factors in dog health. Through analyzing major and trace elements in hair and... 相似文献
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Johanna Salmelin Ilkka Pölönen Hannu-Heikki Puupponen Heikki Hämäläinen Anna K. Karjalainen Ari Väisänen Kari-Matti Vuori 《Water, air, and soil pollution》2018,229(9):308
The applicability of spectral analysis in detection of freshwater metal contamination was assessed by developing and testing a novel hyperspectral imaging (HSI) application for aquatic insect larvae (Trichoptera: Hydropsychidae). Larvae were first exposed to four different cadmium (Cd) concentrations: 0, 1, 10, and 100 μg L?1 for 96 h. Individual larvae were then preserved in ethanol, inspected with microscopy for the number of anomalies in larval gills, and imaged by hyperspectral camera operating with wavebands between 500 and 850 nm. Three additional larvae from each exposure were analyzed for tissue Cd concentration. Although the larval tissue Cd concentrations correlated positively with actual water concentrations, the toxicity response of larvae, i.e., frequency of gill abnormalities, did not differ among the Cd concentrations. In contrast, hyperspectral imaging data indicated some concentration-response relationship of larval spectral properties to the Cd exposure, but it was too weak for reliable automatic distinction between exposed and unexposed larvae. In this pilot study a workflow for data processing for a novel application of hyperspectral imaging was developed. Based on the results of this preliminary study, the workflow in the imaging process will be optimized and its potential for detecting metal contamination of aquatic environments reassessed. 相似文献
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1. The fermentation of poultry manure in an attempt to increase its value for poultry diets was studied.
2. Microbial strains for the efficient elimination of uric acid were isolated.
3. Suitable, cheap carbon sources (methanol, glycerol, glucose) were tested in attempts to increase cell yield.
4. These criteria were used to study the 41 bacterial and 8 yeast strains which were the most prolific on slants and which were isolated from experiments with a shaker. A strain was selected for experimentation with a fermentor.
5. Fermentor experiments were done on a laboratory scale (101) and in a non‐sterile semicontinuous system (150 1), cell mass production being similar in both systems. 相似文献
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Framework for designing and applying peak runoff control structures for peatland forestry conditions
Hannu Marttila Kari-Matti Vuori Hannu Hökkä Juha Jämsen Bjørn Kløve 《Forest Ecology and Management》2010
Drainage-induced diffuse pollution and erosion are key water quality problems in peatland forestry. A major part of the pollutant load is transported during peak runoff periods after snowmelt or intense rainfall. This study investigated possibilities to increase retention time of runoff waters in drained peatland catchments on purpose to diminish peak runoff and improve settling conditions of suspended solids (SS). To create retention, a peak runoff control (PRC) structure was developed and its functioning, dimensioning and practical applications were studied in five partly or completely ditch-drained catchments in Central Finland. The method reduced runoff peaks by 10–73% or 5.07–57.63 l−1 s−1 km−2, and functioned especially well during largest runoff peaks. The effectiveness of the PRC method depended on (i) catchment topography (slope) and available detention volume, (ii) dimensioning and location of the PRC structure, and (iii) runoff rates. The PRC structure is cheap and can easily be created with forest drainage machinery during the ditching and ditch network maintenance operations. Different issues relating to the structural design, water quality benefits, and impacts on forestry are discussed. 相似文献
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