摘要
Atmospheric deposition of nutrients, particularly nitrogen and phosphorus has the capacity to significantly affect the productivity and biogeochemistry of aquatic ecosystems. The objective of this study was to assess the impact of land use/cover types on the atmospheric deposition of nutrients around Lake Kivu. Dry and wet atmospheric deposition samples were collected from four different land use/cover types (forest, wetland, agricultural and urbanized area) at four stations (Goma, Lwiro, Bukavu and Iko) around the Lake Kivu basin. The highest annual loading of dry total phosphorus (TP) was recorded at a station located in an urban area at Goma (4.4 ± 3.9 μmol/m<sup>2</sup>/yr) and the highest dry deposition of total nitrogen (TN) was recorded at Iko (84.5 ± 41.2 μmol/m<sup>2</sup>/yr). High wet TP and TN were at Bukavu (0.7 ± 1.1 μmol/m<sup>2</sup>/yr) and Iko (21.7 ± 34.7 μmol/m<sup>2</sup>/yr) respectively. High dry TP loads were recorded in the forest area of Goma and the highest dry TN at Lwiro. High wet TP loads were record in agriculture at Goma and high values of wet TN in agriculture at Iko. Phosphorus and nitrogen deposition rates around Lake Kivu were similar to those reported for other African lakes. The highest rate of TP was recorded mainly in the forest area for dry deposition while high TN was recorded in all types of land use/cover in the basin. This study found out that forest traps high concentration of nutrient than other land uses/covers.
Atmospheric deposition of nutrients, particularly nitrogen and phosphorus has the capacity to significantly affect the productivity and biogeochemistry of aquatic ecosystems. The objective of this study was to assess the impact of land use/cover types on the atmospheric deposition of nutrients around Lake Kivu. Dry and wet atmospheric deposition samples were collected from four different land use/cover types (forest, wetland, agricultural and urbanized area) at four stations (Goma, Lwiro, Bukavu and Iko) around the Lake Kivu basin. The highest annual loading of dry total phosphorus (TP) was recorded at a station located in an urban area at Goma (4.4 ± 3.9 μmol/m<sup>2</sup>/yr) and the highest dry deposition of total nitrogen (TN) was recorded at Iko (84.5 ± 41.2 μmol/m<sup>2</sup>/yr). High wet TP and TN were at Bukavu (0.7 ± 1.1 μmol/m<sup>2</sup>/yr) and Iko (21.7 ± 34.7 μmol/m<sup>2</sup>/yr) respectively. High dry TP loads were recorded in the forest area of Goma and the highest dry TN at Lwiro. High wet TP loads were record in agriculture at Goma and high values of wet TN in agriculture at Iko. Phosphorus and nitrogen deposition rates around Lake Kivu were similar to those reported for other African lakes. The highest rate of TP was recorded mainly in the forest area for dry deposition while high TN was recorded in all types of land use/cover in the basin. This study found out that forest traps high concentration of nutrient than other land uses/covers.
作者
Mashimango Bagalwa
Jackson Gilbert Mwanjalolo Majaliwa
Harvey Bootsma
Katcho Karume
Sarah Akello
Frank Kansiime
Mashimango Bagalwa;Jackson Gilbert Mwanjalolo Majaliwa;Harvey Bootsma;Katcho Karume;Sarah Akello;Frank Kansiime(College of Agricultural and Environmental Sciences, Makerere University, Kampala, Uganda;Department of Biology, Centre de Recherche en Sciences Naturelles (CRSN/Lwiro), Bukavu, Democratic Republic of Congo;Faculté des Sciences Agronomique et Environnement, Université Evangélique en Afrique, Bukavu, Democratic Republic of Congo;Regional University Forum for Capacity Building in Agriculture (RUFORUM), Kampala, Uganda;School of Freshwater Sciences, University of Wisconsin-Milwaukee, Milwaukee, USA;Observatoire Volcanologique de Goma, Department of Geochemistry and Environment, Goma, Democratic Republic of Congo)
