The rain-runoff response of tropical humid forest ecosystems to use and reforestation in the Western Ghats of India
The rain-runoff response of tropical humid forest ecosystems to use and reforestation in the Western Ghats of India
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印度西高止山脉热带湿润森林生态系统的雨水径流对利用和重新造林的响应
DOI：
10.1016/j.jhydrol.2012.09.016
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发表时间：
2012
影响因子：
6.4
通讯作者：
Krishnaswamy J
中科院分区：
文献类型：
--
作者：
Krishnaswamy J
在多年代际时间尺度上，森林退化以及人工林的使用和建立对退化或改良的森林生态系统的影响，与毁林和森林转用农业相比，在潮湿热带地区研究较少。在印度的西高塞山脉（北方邦，卡纳塔克邦），之前的一项与降雨IDF（强度-持续时间-频率）相关的土壤水力导电性调查表明，在退化的森林和重新造林的地区，更容易发生过量的陆地渗透，因此可能会有更高的流量（Bonell等人，2010）。为了进一步验证这些预测，我们在北方邦建立了3个生态系统(1)残余热带常绿森林（NF）、(2)退化森林（DF）和(3)退化前林地上的外来金合欢人工林（AC、金合欢），范围从7公顷到23公顷不等的实验盆地。总共有11个盆地（3个NF， 4个AC和4个DF）在两个地貌带，即沿海和上高峰（Malnaad）和三个地点（一个沿海，两个上高峰）被测量。分析了在2003-2005年2 - 3年期间（2003-2005年）收集到的降水-流量观测资料（每日和36分钟时间分辨率）。在沿海和高原流域，双质量曲线在雨季表现出一致的趋势，即DF>AC>NF等次的流量比例更大。这些双质量曲线提供了强有力的证据，表明陆地流逐渐成为一个更主要的风暴流途径。在所有站点中，NF将28.4±6.41stdev%的降雨量转化为总流量，而AC为32.7±6.97stdev%， DF为45.3±9.61stdev%。对上述趋势的进一步支持来自沿海盆地的快速流动比率QF/Q。DF和AC的土地覆被及其等级顺序DF>AC>NF都有更高的值。DF流域的快流响应比QF/P也最高，随着QF/Q比的增加，可超过90%。相应的延迟流响应比（QD/P）清楚地显示了最大的QD产量占森林事件降水的比例（NF1）。线性模型的应用支持了沿海盆地风暴水文响应的这些差异（如NF与DF之间的10-36%差异，p<0.001）。唯一的例外是QF/P，它与流域间平均差异有较高的不确定性。沿海盆地三次风暴事件的雨流相互关联图和相应的滞后回归模型表明，与AC在~ 1和16h以及DF在~ 1和12h分别出现双峰峰相比，在NF中存在多重滞后的替代风暴流路径。NF的长时间滞后表明深层地下暴雨流和地下水是暴雨线的贡献源。DF和AC的短时间滞后表明地表流动，因此AC保留了以前退化的土地覆盖的“记忆”，这得到了以前的水力传导率数据的支持。由于潜在蒸散和实际蒸散在季风期间可能被抑制，不同土地覆盖类型之间的流量和径流响应的差异主要归因于土壤入渗和水文途径的差异。应在其他生态系统服务和生物多样性的背景下探讨在管理生态系统中增加入渗和减少径流的问题。
The effects of forest degradation and use and establishment of tree-plantations on degraded or modified forest ecosystems at multi-decadal time-scales using tree-plantations on the streamflow response are less studied in the humid tropics when compared to deforestation and forest conversion to agriculture. In the Western Ghats of India (Uttar Kannada, Karnataka State), a previous soil hydraulic conductivity survey linked with rain IDF (intensity–duration–frequency) had suggested a greater occurrence of infiltration-excess overland within the degraded forest and reforested areas and thus potentially higher streamflow (Bonell et al., 2010). We further tested these predictions in Uttar Kannada by establishing experimental basins ranging from 7 to 23ha across three ecosystems, (1) remnant tropical evergreen Forest (NF), (2) heavily-used former evergreen forest which now has been converted to tree savanna, known as degraded forest (DF) and (3) exotic Acacia plantations (AC, Acacia auriculiformis) on degraded former forest land. In total, 11 basins were instrumented (3 NF, 4 AC and 4 DF) in two geomorphological zones, i.e., Coastal and Up-Ghat (Malnaad) and at three sites (one Coastal, two Up-Ghat). The rainfall–streamflow observations collected (at daily and also at a 36min time resolutions in the Coastal basins) over a 2–3year period (2003–2005) were analysed. In both the Coastal and Up-Ghat basins, the double mass curves showed during the rainy season a consistent trend in favour of more proportion of streamflow in the rank order DF>AC>NF. These double mass curves provide strong evidence that overland flow is progressively becomes a more dominant stormflow pathway. Across all sites, NF converted 28.4±6.41stdev%of rainfall into total streamflow in comparison to 32.7±6.97stdev%in AC and 45.3±9.61stdev%in DF. Further support for the above trends emerges from the quickflow ratio QF/Q for the Coastal basins. There are much higher values for both the DF and AC land covers, and their rank order DF>AC>NF. The quickflow response ratio QF/P is also the highest for the DF basin, and along with the QF/Q ratio, can exceed 90%. The corresponding delayed flow response ratios, QD/P clearly show the largest QDyields as a proportion of event precipitation from the Forest (NF1). The application of linear model supported these differences (e.g. 10–36% difference between NF and DF, p<0.001) in the storm hydrologic response of the Coastal basins. The exception was QF/P where there was a higher uncertainty connected with inter-basin mean differences. Cross-correlation plots for rain–streamflow and corresponding lag regression models for three storm events in the Coastal basins suggested the existence of alternative stormflow pathways with multiple lags with peaks between ∼12 and 24h in NF, compared to respective bimodal peaks at ∼1 and 16h in AC and ∼1 and 12h in DF. The long time lags for NF are suggestive of deep subsurface stormflow and groundwater as the contributing sources to the storm hydrograph. The short time lags in DF and AC are indicative of overland flow and so ‘memory’ of the previous degraded land cover is retained in AC as supported by previous hydraulic conductivity data. As potential and actual evapotranspiration is likely to be depressed during the monsoon, differences in streamflow and run-off responses between land-cover types is largely attributed to differences in soil infiltration and hydrologic pathways. Enhancing infiltration and reducing run-off in managed ecosystems should be explored in the terms of the context of other ecosystem services and biodiversity.
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DOI：
10.1007/978-4-431-46503-4
发表时间：
2007
期刊：
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影响因子：
--
作者：
H. Sawada;M. Araki;N. Chappell;J. Lafrankie;A. Shimizu
通讯作者：
H. Sawada;M. Araki;N. Chappell;J. Lafrankie;A. Shimizu
使用张力渗透仪现场测量不饱和水力传导率。
DOI：
--
发表时间：
2002
期刊：
影响因子：
--
作者：
N. Mckenzie;H. Cresswell;T. W. Green;N. Mckenzie;K. Coughlan;H. Cresswell
通讯作者：
H. Cresswell
南印度森林地图说明手册。
DOI：
--
发表时间：
1986
期刊：
影响因子：
--
作者：
J. Pascal
通讯作者：
J. Pascal
热带地区人工林的水流失
DOI：
--
发表时间：
2008
期刊：
影响因子：
--
作者：
J. Kallarackal;C. Somen
通讯作者：
C. Somen
源头集水区的径流过程——印度南部西高止山脉的一项实验研究
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
M. Putty;R. Prasad
通讯作者：
R. Prasad