Land In Dry Season Research Articles

Diversity and length-weight relationships of fishes from Lake Cala in tide season

Lake Cala, a fishery potential oxbow lake, is located in Musi Banyuasin, South Sumatra. Lake Cala is a wetland that flooded during high tide and become land in dry season. The study was conducted to determine present status of the diversity and the condition of fish. This study has been done at Lake Cala in February until March 2017. On this tide season, data were collected by fishers. The fish sampling was conducted using hook line, cast nets, gillnets and fish traps (corong). A total of 27 fish species belongs to three ordo,11 families, and 19 genera were recorded during the study. Diversity of fish in Lake Cala on the tide season is dominated by whitefishes. Based on its potency, most fish species are 59% consumption, 33% double potency, and 8% ornamental fish. Aro (Osteochilus melanopleura) and palau (O. vittatus) from Cyprinidae family, and baung (Mystus nemerus) from Bagridae family were dominant. The length-weight relationship showed that dominant two species of fish (baung and palau) had positive allometric growth patterns, while aro is isometric. Those parameters obtained from the study are useful fundamental information applicable in the future population dynamics studies. Furthermore, based on these result it was necessary to manage the fishing gears operation and regulating tributaries to maintain the process of fish on search for feed, distribution, and colonization of various species and populations.

赣江流域土地利用方式对河流水质的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 赣江流域土地利用方式对河流水质的影响 DOI: 10.5846/stxb201409221870 作者: 作者单位: 1. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室;2. 江西师范大学地理与环境学院,1. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室;2. 江西师范大学地理与环境学院,1. 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室;2. 江西师范大学地理与环境学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(41201033, 41261069); 鄱阳湖湿地与流域研究教育部重点实验室(江西师范大学)主任开放基金项目(ZK2013009); 江西省土壤侵蚀与防治重点实验室开放研究基金项目(JXSB201302); 江西省重大生态安全问题监控协同创新中心资助项目(JXS-EW-00) Influence of land use on river water quality in the Ganjiang basin Author: Affiliation: 1. Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University; 2. School of Geography and Environment, Jiangxi Normal University,1. Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University; 2. School of Geography and Environment, Jiangxi Normal University,1. Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University; 2. School of Geography and Environment, Jiangxi Normal University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:赣江是鄱阳湖的最大支流,是鄱阳湖水污染物的主要来源,查明流域土地利用方式对赣江水质的影响和鄱阳湖的水环境保护具有重要意义。基于2012年对赣江7个主要支流NH4+-N、TP、CODMn和DO浓度的每月测定结果,通过不同空间尺度和土地类型等级划分,利用相关分析和冗余分析研究土地利用方式对赣江流域河流水质的影响。研究结果表明,子流域的土地利用方式对TP的影响大于缓冲区;对CODMn的影响在丰水期大于缓冲区,在枯水期小于缓冲区;对NH4+-N的影响在丰水期与缓冲区接近,在枯水期小于缓冲区;DO受土地利用方式的影响较小。水田中的丘陵水田是赣江水体TP和丰水期CODMn的主要来源;平原水田是枯水期CODMn的主要来源。居民建设用地中的城镇用地是赣江水体TP、NH4+-N和丰水期CODMn的主要来源,农村用地是CODMn的主要来源。水域中的水库坑塘是赣江水体TP和丰水期NH4+-N、CODMn的主要来源。 Abstract:The global transition from undisturbed to human-dominated landscapes has impacted river water quality worldwide and made the quantification of land use a valuable indicator of water pollutant. The Ganjiang River, as the largest tributary of the Poyang Lake Basin, is the main pollution source of the Poyang Lake. Identifying the influence of land use on water quality in the Ganjiang River has great significance for water environment protection in the Poyang Lake. In this study, we investigated the monthly concentration of NH4+-N, TP, CODMn and DO in seven major tributaries of the Ganjiang River in 2012 and analyzed the influence of land use on river water quality by the methods of correlation analysis and redundancy analysis. Two spatial scales, the sub-basin and buffer zone, and two levels of land use classification were considered. The first level of land use classification was paddy field, dry farm, forest land, grass land, water area, resident construction land and unused land, resulting from remote sensing image interpretation. The second level of land use classification was obtained from the first level based on different geomorphology, canopy density, grass coverage and other factors. The results showed that forest was the largest land use pattern in the study area, followed by paddy field and dry farm. The concentration of TP had a significant positive correlation with NH4+-N in wet season, while NH4+-N had a significant negative correlation with DO in dry season. The pollution sources of TP both in wet season and dry season were from hill paddy field, urban land, reservoir and pond. The pollution sources of CODMn were from paddy field, urban land, reservoir and pond, and rural residential land in wet season, while from plain paddy field and rural residential land in dry season. The pollution sources of NH4+-N were from urban land, reservoir and pond in wet season, while from urban land, mountainous dry farm, riparian forest land and low coverage grassland in dry season. Additionally, different spatial scales of land use had different impacts on water quality indicators. The land use in sub-basin had more influence on TP and wet seasonal CODMn than that in buffer zone, while it had less influence on dry seasonal CODMn than that in buffer zone. For NH4+-N, the land use in sub-basin had similar influence as that in buffer zone in wet season, while less influence than that in buffer zone in dry season. The impact of land use on DO was not significant. Moreover, we found that it was more helpful to study the source of the river water pollutant based on the second level of land use classification than the first level of land use classification. Among the paddy field, hill paddy field was the main source of TP and wet seasonal NH4+-N; while plain paddy field was the main source of dry seasonal CODMn. Among the residential construction land, urban land was the main source of TP, NH4+-N, and wet seasonal CODMn, while rural residential land was the main source of CODMn. Among the water area, reservoir and pond were the main source of TP, wet seasonal NH4+-N and wet seasonal CODMn. 参考文献 相似文献 引证文献