| dc.contributor.author | Lacoul, Paresh. | en_US |
| dc.date.accessioned | 2014-10-21T12:38:49Z | |
| dc.date.available | 2004 | |
| dc.date.issued | 2004 | en_US |
| dc.identifier.other | AAINQ89805 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/54611 | |
| dc.description | Aquatic plants and physical-chemical characteristics were studied in 34 lakes at altitudes ranging from tropical (77 m) to high-alpine (4,950 m) in the Himalayas of Nepal. The water chemistry was dominated by HCO3 - among anions, and by Cat2+ and Mg2+ among cations. Criteria related to total phosphorus, total nitrogen, and chlorophyll showed that lakes in the High Himal (HH) and High Mountain (HM) regions are oligotrophic, while those in the Middle Mountains (MM) were oligotrophic to hypereutrophic, and Terai (TE) lakes were eutrophic to hypereutrophic. | en_US |
| dc.description | Aquatic macrophytes occurred in 28 lakes, up to an altitude of 4,750 m. Both species richness and diversity of aquatic macrophytes showed approximately linear decreases with increasing altitude. The study region exhibits a relatively high proportion of monocotyledonous helophytes and hyperhydates, as is typical of aquatic macrophytes on the Indian subcontinent. | en_US |
| dc.description | A canonical correspondence analysis of the steepest altitudinal gradient (CCA-1) suggested that the strongest abiotic influences on the distribution of macrophytes are associated with water temperature, substrate quality, altitude, pH, transparency, and conductivity. Two more restricted CCA analyses examined a shorter altitudinal gradient of 70 m to 1500 m. The CCA-2 analysis (all plants) and CCA-3 (only euhydrophytes) found that the most important abiotic influences were associated with temperature, lake surface area, suspended solids, bicarbonate, and dissolved phosphorus. These results suggest that relatively local influences are different from those that have a regional basis, but that climatic influences are key along altitudinal gradients. The temperature gradient in the CCA distinguished Arcto-tertiary floristic elements of the HH and HM regions from the more widely distributed temperate and tropical species of the MM and TE regions. This observation is also supported by the results of a cluster analysis. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 2004. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Agriculture, Fisheries and Aquaculture. | en_US |
| dc.title | Aquatic macrophyte distribution in response to physical and chemical environment of the lakes along an altitudinal gradient in the Himalayas, Nepal. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
