Land use regulates carbon budgets in eastern Germany: From NEE to NBP
Land use regulates carbon budgets in eastern Germany: From NEE to NBP
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DOI：
10.1016/j.agrformet.2010.03.008
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发表时间：
2010-07-15
影响因子：
6.2
通讯作者：
Bernhofer, Christian
中科院分区：
文献类型：
--
作者：
Prescher, Anne-Katrin;Gruenwald, Thomas;Bernhofer, Christian
大气中的二氧化碳浓度受土地利用和管理的影响。在这里，比较了被管理的森林(云杉)、草场和作物地(轮作)的碳(CO2-C)预算，以考察不同管理做法对净生态系统交换(NEE)和净生物群生产力(NBP)的影响。这种办法能够更全面地编制碳预算，因为它考虑到了特定土地用途的碳出口和进口。基于涡度协方差(EC)方法测得的净现值，我们还考虑了由于间伐或收获造成的碳出口和由于有机肥料造成的碳进口，从而量化了净基准值。这些遗址是德国东部塔兰特集群的一部分，该集群的特点是天气和气候只有微小的差异。因此，管理对C预算的影响可以与其他驱动因素区分开来。对于森林立地，从1997年到现在有连续的CO2通量测量，草地和农田立地的共同研究周期是2005-2008年(一次轮作)。仅当考虑森林的年需氧量时，净汇的变化范围在-698gCm(-2)(1999)到-444gCm(-2)(2003)之间，而草地和农田的净汇分别在-177gCm(-2)(2004)和-62gCm(-2)(2005)和-115gCm(-2)(2005)和-32gCm(-2)(2007和2008)之间。该林地是一个碳源，2002年的NBP+221gCm(-2)是因为类似于43m(3)ha(-1)的实木被移除。草地的碳源和碳汇交替变化，由于每年几次碳汇的输出，NBP在+25gCm(-2)(2008)到-28gCm(-2)(2006)之间变化。农田立地主要受种植作物种类和有机肥(有机肥)施用量的影响，NBP值介于+484gCm(-2)(2007)和-89gCm(-2)(2006)之间。不同的冬春作物生长季的时间和长度导致了不同的NEE年内模式，以及较低的春作物年净二氧化碳汇。已经为作物收割日期之后立即开始的所有地点定义了替代会计期间。根据整个轮作周期(约4年)，NBP显示云杉地的碳汇和作物轮作的碳源。根据计算的NBP，草场为C中性。(C)2010爱思唯尔B.V.保留所有权利。
The concentration of carbon dioxide in the atmosphere is influenced by land use and management. Here, the carbon (CO2-C) budgets of a managed forest (spruce), a grass site and a crop site (crop rotation) have been compared to examine the effects of different management practices on net ecosystem exchange (NEE) and net biome productivity (NBP). This approach enables a more comprehensive carbon budgeting as it takes into account carbon exports and imports for particular land uses. Based on NEE measured with the eddy covariance (EC) method, we quantified NBP by also considering the carbon exports due to thinning or harvest and the carbon imports due to organic fertilisation. The sites are part of the Tharandt cluster in eastern Germany, characterised as having only slight differences in weather and climate. As a result, the management effects on the C budgets can be distinguished from other drivers. For the forest site, continuous CO2 flux measurements are available from 1997 to today, and the common study period of the grassland and cropland sites is 2005-2008 (one crop rotation). Only when considering the forest's annual NEE was there a variability in the net sink from -698 g C m(-2) (1999) to -444 g C m(-2) (2003), whereas the grassland and cropland sites exhibited small sinks between -177 g C m(-2) (2004) and -62 g C m(-2) (2005) and between -115 g C m(-2) (2005) and -32 g C m(-2) (2007 and 2008), respectively. The forest site is a carbon source with an NBP +221 g C m(-2) in 2002 because similar to 43 m(3) ha(-1) solid wood was removed. The grassland alternated between carbon sources and sinks, with NBP ranging from +25 g C m(-2) (2008) to -28 g C m(-2) (2006) due to carbon export through several cuts per year. The cropland site was mainly influenced by the cultivated crop species and the application of organic fertiliser (manure), resulting in NBP values between +484 g C m(-2) (2007) and -89 g C m(-2) (2006). The different timing and length of the growing season for winter and spring crops result in different intra-annual patterns of NEE as well as lower annual net CO2 sinks for the spring crops. Alternative accounting periods have been defined for all sites starting immediately after the harvest date at the crop site. Based on the full crop rotation period (around 4 years), the NBP showed a C sink for the spruce site and a C source for the crop rotation. The grass site was C neutral according to the calculated NBP. (C) 2010 Elsevier B.V. All rights reserved.