Seasonal Variation in Whole Stream Metabolism across Varying Land Use Types
Seasonal Variation in Whole Stream Metabolism across Varying Land Use Types
复制标题
不同土地利用类型的全流代谢的季节性变化
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
Ad Hart
中科院分区：
文献类型：
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作者：
Ad Hart
从历史上看，整个流明渠代谢已被测量在短时间内与营养注入，以评估流内的营养动态。本研究的目的是了解溪流内和溪流间代谢的季节变化，以及不同土地利用方式的影响。这是通过监测九个不同的流域在小田纳西河流域西南部北卡罗来纳州。九个研究流域被选中代表森林，农业和发达的土地利用/土地覆盖类型的梯度。部署了数据记录器，以收集2010-2011年的连续氧气、温度、电导率和载物台高度数据。我用这些数据来估计总初级生产力（GPP）和生态系统呼吸（ER）。GPP和ER进行了比较流化学，光，土地覆盖和风暴。研究发现，当地河岸土地覆盖对GPP和ER的影响大于流域土地覆盖。溪流的年GPP各不相同，但一般来说，GPP的峰值出现在冬末春初，低谷出现在秋季。GPP是最强烈的影响，可用光的量，这是直接相关的冠层覆盖量。ER比GPP更易变流内和流之间，但一般在夏季达到峰值，在冬季最低。ER是最强烈相关的农业用地覆盖的比例在当地河岸区。我的研究结果表明，当地河岸植被可能有更大的影响代谢比山腰的发展。
Historically, whole stream open channel metabolism has been measured over short periods in conjunction with nutrient injections to assess nutrient dynamics within streams. The purpose of my study was to understand the seasonal changes in metabolism within and among streams as well as the impacts of different land use. This was addressed by monitoring nine different watersheds in the Little Tennessee River watershed in southwestern North Carolina. The nine study watersheds were selected to represent a gradient of forested, agricultural, and developed land use / land cover types. Data loggers were deployed to collect continuous oxygen, temperature, conductivity, and stage height data from 2010-2011. I used these data to estimate gross primary production (GPP) and ecosystem respiration (ER). GPP and ER were compared to stream chemistry, light, land cover, and storms. I found that there is greater influence of local riparian land cover than watershed land cover on GPP and ER. Streams had varying annual GPP, but generally the peak in GPP occurred in late winterearly spring with lows in fall. GPP was most strongly influenced by the amount of available light, which is directly related to the amount of canopy cover. ER was much more variable than GPP within and among streams but generally peaked in summer and was lowest in the winter. ER was most strongly related to the proportion of agricultural land cover in the local riparian area. My results suggest that local riparian vegetation may have a greater impact on metabolism than mountainside development.