Arbuscular mycorrhizas influence plant diversity, productivity, and nutrients in boreal grasslands

2004 ◽  
Vol 82 (1) ◽  
pp. 104-114 ◽  
Author(s):  
Shivcharn S Dhillion ◽  
Tone L Gardsjord
Keyword(s):  
Arbuscular Mycorrhiza ◽  
Plant Diversity ◽  
Arbuscular Mycorrhizas ◽  
Phosphorus Concentration ◽  
Inoculum Potential ◽  
Nitrogen And Phosphorus ◽  
Higher Plant ◽  
Nutrient Contents ◽  
Mycorrhizal Inoculum Potential ◽  
Total Productivity

The effect of reduced arbuscular mycorrhiza (AM) colonization on nitrogen and phosphorus concentration in grass tissue, species diversity, cover, and productivity was investigated after 4 years of benomyl application in two boreal grasslands, Storvordlia (a high plant diversity field) and Kalvsvangen (a low plant diversity field), in Eastern Norway. In addition, AM colonization, spore numbers, and mycorrhizal inoculum potential was studied during one season. A split-plot design was used, with grazing as the main treatment and the application of benomyl as a subtreatment. AM colonization was significantly reduced because of benomyl application, whereas spore numbers were not significantly affected by the treatment. Mycorrhizal inoculum potential was reduced, but not consistently. In both sites nitrogen and phosphorus concentration of grass tissue was significantly higher in grazed plots than in ungrazed ones, and significantly lower in benomyl subplots than in controls. Plant diversity, composition, and cover had changed significantly after 4 years in grazed controls in Storvordlia, but this was not seen in Kalvsvangen. In both sites, total productivity increased significantly after 4 years of benomyl application. This experiment indicates that AM associations can influence grass nutrient contents and species responses, plant diversity, and productivity in boreal grasslands. These differences were larger in the higher plant diversity site, which is situated at a higher elevation and is under more marginal growth conditions.Key words: arbuscular mycorrhiza, benomyl, productivity, biodiversity, boreal grasslands, ecosystem processes.

Decomposition of aspen, spruce, and pine boles on two sites in Minnesota

1993 ◽  
Vol 23 (9) ◽  
pp. 1744-1749 ◽  
Author(s):  
David H. Alban ◽  
John Pastor
Keyword(s):  
Nutrient Content ◽  
Magnesium Content ◽  
Jack Pine ◽  
Red Pine ◽  
Phosphorus Concentration ◽  
Quaking Aspen ◽  
Nitrogen And Phosphorus ◽  
Nutrient Contents ◽  
Decomposition Constant ◽  
Nitrogen Concentrations

Boles of quaking aspen (Populustremuloides Michx.), white spruce (Piceaglauca (Moench) Voss), red pine (Pinusresinosa Ait.), and jack pine (Pinusbanksiana Lamb.) were sampled after decomposing for 11–17 years. Mass loss and changes in chemical composition were determined. Density decreased by 40–73%, and the decomposition constant (k) decreased in the order aspen > spruce > red pine > jack pine. Although the decomposition rate was strongly species dependent, it did not differ between the two sites. The decomposition constant was weakly related to lignin and phosphorus concentration in the original stems (r2 = 0.44 and 0.49, respectively) and not significantly related to original nitrogen concentrations. Nutrient concentration increased during decomposition, particularly for nitrogen and phosphorus. Nitrogen content increased during decomposition, and potassium content decreased. Calcium and magnesium content changed little during decomposition, whereas phosphorus content increased or decreased, depending on species. In general, species with the lowest initial nutrient contents had the greatest nutrient increases during decomposition. Nutrient content of boles of all species became similar during decomposition.

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.

Nitrogen and phosphorus in the Vistula River, Poland -- changes from source to mouth

1994 ◽  
Vol 30 (5) ◽  
pp. 177-186 ◽  
Author(s):  
Karin Sundblad ◽  
Andrzej Tonderski ◽  
Jacek Rulewski
Keyword(s):  
Central Region ◽  
Northern Region ◽  
Point Sources ◽  
Nutrient Loss ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Concentration Data ◽  
Diffuse Sources ◽  
Vistula River ◽  
South Central

Nitrogen and phosphorus concentration data representing samples collected once a month for nine months at 13 locations along the Vistula River are considered in a preliminary discussion of the sources of the nutrients transported to the Baltic Sea. Concentrations in relation to flow data indicated substantial differences between subbasins. Based on those differences, on the area-specific nutrient loss for a six-month period and on the wastewater discharge in each subbasin, four regions could be recognized in the river basin: i) the southern region with a large impact of point sources, ii) the south central region, where diffuse sources seemed to be of major importance, iii) the north central region with a combined effect of point and diffuse sources, and retention in two reservoirs, iv) the northern region where point sources seemed to be the dominating source, at least for phosphorus. Our results illustrate the importance of differences in phosphorus retention between the basins. Long-term retention along the course of the river, particularly in the two reservoirs, must be estimated to allow proper source apportionment in the Vistula basin. Concentration decreases in the Wloclawek Reservoir varied between 44 and 68% for P, and 11 to 37% for N, in the months with significant retention. In some months, however, concentrations increased, indicating a release of nutrients.

scholarly journals Retrieval and Evaluation of Chlorophyll-a Concentration in Reservoirs with Main Water Supply Function in Beijing, China, Based on Landsat Satellite Images

2021 ◽  
Vol 18 (9) ◽  
pp. 4419
Author(s):  
Yuequn Lai ◽  
Jing Zhang ◽  
Yongyu Song ◽  
Zhaoning Gong
Keyword(s):  
Remote Sensing ◽  
Water Supply ◽  
Chlorophyll A ◽  
Phosphorus Concentration ◽  
Landsat 8 ◽  
Supply Function ◽  
Estimation Model ◽  
Nitrogen And Phosphorus ◽  
Chlorophyll A Concentration ◽  
Guanting Reservoir

Remote sensing retrieval is an important technology for studying water eutrophication. In this study, Guanting Reservoir with the main water supply function of Beijing was selected as the research object. Based on the measured data in 2016, 2017, and 2019, and Landsat-8 remote sensing images, the concentration and distribution of chlorophyll-a in the Guanting Reservoir were inversed. We analyzed the changes in chlorophyll-a concentration of the reservoir in Beijing and the reasons and effects. Although the concentration of chlorophyll-a in the Guanting Reservoir decreased gradually, it may still increase. The amount and stability of water storage, chlorophyll-a concentration of the supply water, and nitrogen and phosphorus concentration change are important factors affecting the chlorophyll-a concentration of the reservoir. We also found a strong correlation between the pixel values of adjacent reservoirs in the same image, so the chlorophyll-a estimation model can be applied to each other.

scholarly journals Simplicity or complexity? Important aspects of high nature value grassland management in nature conservation

2021 ◽  
Author(s):  
Róbert Kun ◽  
Dániel Babai ◽  
András István Csathó ◽  
Csaba Vadász ◽  
Nikoletta Kálmán ◽  
...  
Keyword(s):  
Nature Conservation ◽  
Plant Diversity ◽  
Management Practices ◽  
Grassland Management ◽  
Plant Functional Types ◽  
Higher Plant ◽  
Temporal Complexity ◽  
Functional Types ◽  
Management Factors ◽  
Spatio Temporal

AbstractLocal, adaptive traditional grassland management systems have played a fundamental role in the creation, maintenance and conservation of high nature value (HNV) grasslands. The state of diverse HNV grasslands has deteriorated across Europe in conjunction with changes in various management factors, such as management type and management intensity. To conserve the species-rich vegetation of HNV grasslands and to avoid undesirable shifts in plant functional type dominance, it is important to explore the effects of management factors crucial for nature conservation and to adapt them to local circumstances. In our study, we focus on three of the main factors in the management of valuable meadow steppes in the Great Hungarian Plain region (Central Hungary). We studied management types (mowing, grazing and combined), different levels of herbage removal intensity (low, medium, high) and spatio-temporal complexity (low, medium and high) of grassland management. Altogether 172 plots (1 m × 1 m) were designated in 17 sites. Plant diversity indexes and plant functional types were calculated according to the presence and percentage cover of plant species in the plots. Regarding plant diversity and the dominance of plant functional types, herbage removal intensity and spatio-temporal complexity of management had, for the most part, stronger effects than the type of management. Higher spatio-temporal complexity of management resulted in higher plant diversity, while higher intensity of management led to significantly lower diversity. Proper application of type, intensity and spatio-temporal complexity of management practices (separately and in combination) proved to be determining factors in the long-term maintenance and conservation of diversity and species composition of HNV grasslands.

scholarly journals Species ethnobotanical values rather than regional species pool determine plant diversity in agroforestry systems

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel K. N’Woueni ◽  
Orou G. Gaoue
Keyword(s):  
Species Diversity ◽  
Plant Species ◽  
Plant Diversity ◽  
Agroforestry Systems ◽  
Natural Vegetation ◽  
Species Pool ◽  
Higher Plant ◽  
Natural Habitats ◽  
Natural Systems ◽  
Regional Species Pool

AbstractThe conversion of natural systems into farms and agroecosystems is the main cause of biodiversity loss. In human-dominated landscapes, understanding the interactions between agroforestry systems and adjacent natural vegetation is fundamental to developing sustainable agricultural systems. Species can move between these two systems with natural systems providing the regional pool of species that shape the agricultural values and conservation value of the agroforestry systems. We investigated the influence of neighboring natural habitats on traditional agroforestry systems in the buffer zone of Pendjari Biosphere Reserve in Benin to understand the contribution of regional processes on the quality of agroforestry systems. We expected that agroforestry parklands adjacent to natural vegetation with high species diversity will also have higher plant species diversity. We found no similarity in plant species composition between agroforestry systems and adjacent natural habitats. A small proportion of species in adjacent natural habitats were found in agroforestry systems. The proportion of shared species was not significantly influenced by plant diversity in adjacent natural habitats or the distance from the agroforestry systems to the natural adjacent habitat. However, plant diversity in agroforestry systems was strongly associated with site ethnobotanical values indicating that farmers act as a supplemental but severe environmental filter of the regional species pool. Our study suggests that promoting the plantation of plants with high ethnobotanical use-value is a potentially viable strategy for sustainable agriculture and ecological restoration in Biosphere reserves.

scholarly journals Effect of nitrogen and phosphorus concentration on colony growth of Microcystis flos-aquae in Lake Taihu

2014 ◽  
Vol 26 (2) ◽  
pp. 213-220 ◽  
Author(s):  
XU huiping ◽  
◽  
YANG Guijun ◽  
ZHOU Jian ◽  
QIN Boqiang ◽  
...  
Keyword(s):  
Lake Taihu ◽  
Colony Growth ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus
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