...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Limnologica >Critical phosphorus loading of different types of shallow lakes and the consequences for management estimated with the ecosystem model PCLake
【24h】

Critical phosphorus loading of different types of shallow lakes and the consequences for management estimated with the ecosystem model PCLake

机译：用生态系统模型PCLake估算不同类型浅湖的临界磷负荷及其对管理的后果

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Shallow lakes typically can be in one of two contrasting states: a clear state with submerged macrophytes or a turbid state dominated by phytoplankton. Eutrophication may cause a switch from the clear to the turbid state, if the phosphorus loading exceeds a critical value. Recovery of the clear state is difficult as the critical loading for the switch back during oligotrophication is often lower. A system of interacting ecological processes makes both states stabilize themselves causing the observed hysteresis. The ecosystem of shallow lakes is analysed with PCLake, a dynamic model of nutrient cycling and biota - including phytoplankton, rnacrophytes and a simplified food web. The model was used to calculate the switchpoints in terms of critical phosphorus loading levels for a number of lake types. It turned out that the predicted critical phosphorus loadings differ per lake type, e.g. they decrease with lake area, mean depth and retention time, increase with relative marsh area and fishing intensity, and differ per sediment type. The findings were grossly comparable with empirical evidence. These outcomes were also used to build a metamodel. The results may be useful for lake management, by comparing the critical loadings for a given lake with the actual loading. If the actual loading clearly exceeds the upper switchpoint, nutrient reduction measures are recommended. If the loading approaches the upper switchpoint, or is in the intermediate range, a manager could try to increase the critical loading values of the lake, e.g. by hydromorphological measures. If the loading is well between the two switchpoints, an alternative is to force a switch by direct food web management. (C) 2008 Elsevier GmbH. All rights reserved.
机译：浅湖通常可以处于两种相反的状态之一：大型水生植物被淹没的清澈状态，或以浮游植物为主的混浊状态。如果磷负荷超过临界值，则富营养化可能导致从透明状态变为浑浊状态。清除状态的恢复很困难，因为在低营养化过程中切换回去的临界负载通常较低。相互作用的生态过程系统使两个状态稳定下来，导致观察到的滞后现象。用PCLake分析浅湖的生态系统，PCLake是营养循环和生物区系的动态模型-包括浮游植物，裸藻类植物和简化的食物网。该模型用于计算许多湖泊类型的临界磷负荷水平的转换点。结果表明，预测的临界磷负荷随湖泊类型的不同而不同，例如它们随湖泊面积，平均深度和停留时间而减少，随相对沼泽面积和捕捞强度而增加，并且随沉积物类型而不同。这些发现与经验证据大致可比。这些结果还用于构建元模型。通过将给定湖泊的临界负荷与实际负荷进行比较，结果可能对湖泊管理有用。如果实际负荷明显超过上限转换点，则建议采取营养减少措施。如果负载接近上限开关点或处于中间范围内，则管理员可以尝试增加湖泊的临界负载值，例如通过水形学方法。如果两个开关点之间的负载很好，另一种方法是通过直接食物网管理来强制进行开关。 （C）2008 Elsevier GmbH。版权所有。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号