Key Laboratory for the Eco-Environment of the Three Gorges Reservoir Region of the Ministry of Education, College of Life Sciences, Southwest University, Chongqing, 400715, People's Republic of China.
Environ Sci Pollut Res Int. 2013 Oct;20(10):7112-23. doi: 10.1007/s11356-013-1878-4. Epub 2013 Jun 7.
Pterocarya stenoptera is a native deciduous tree species and a candidate for reforestation in the riparian zones of the Three Gorges Reservoir Region of Yangtze River in China. Water treatments of continuous flooding (CF) and periodic flooding-drought (PF) were applied to examine the growth dynamics of 4-month-old P. stenoptera seedlings and its effects on soil chemical properties. Results showed that P. stenoptera seedlings in both CF and PF significantly decreased leaf biomass accumulation and the height and diameter growth as compared to that in control (CK; treatment with well-watered, well-drained soil), respectively. There was no significant difference in stem biomass among the three groups, but root biomass in PF showed severe reduction compared to that in both CK and CF. Total biomass in PF was significantly decreased compared to that in CK, but comparable to that in CF. Furthermore, no significant difference was found between CF and CK in total biomass. Water treatments in the unplanted soil pots significantly influenced soil pH, soil organic matter (OM), total nitrogen (TN), and alkali hydrolysable nitrogen (AN) contents, in contrast to no significant effects in total phosphorus (TP), total potassium (TK), available phosphorus (AP), and available potassium (AK) contents. In P. stenoptera soils, there were significant effects by water treatment, time, and treatment × time in the eight tested soil chemical properties, except treatment in TK and time effect in OM content. Compared to unplanted soils, the growth of P. stenoptera seedlings significantly increased soil pH value and OM, TN, TP, and TK contents, while decreasing AN, AP, and AK contents in CK group, augmented the mean value of each of the tested soil chemical properties with an exception of AK content in CF group, and increased soil pH value and TN, AN, TP, and AP contents with no significant differences in OM, TK, and AK contents in PF group. Given the fact that TN and TP contents significantly increased in P. stenoptera soils as compared to those in unplanted soils, growth of P. stenoptera seedlings should be a successful candidate for restoration within the highly dynamic hydrologic zone of the riparian zones of the Three Gorges Reservoir Region.
枫杨是中国长江三峡库区河岸带的乡土落叶树种，也是河岸带植被恢复的候选树种之一。本研究采用连续水淹（CF）和周期性水淹-干旱（PF）两种水分处理方式，研究了 4 月龄枫杨幼苗的生长动态及其对土壤化学性质的影响。结果表明，与对照（CK，土壤水分充足、排水良好）相比，CF 和 PF 处理下枫杨幼苗的叶片生物量积累、株高和地径生长均显著降低。3 种处理方式下，枫杨幼苗的茎生物量无显著差异，但 PF 处理下的根生物量与 CK 和 CF 相比显著减少。PF 处理下的总生物量显著低于 CK，但与 CF 处理相当。此外，PF 处理下的总生物量与 CK 相比无显著差异。未种植土壤盆中的水分处理方式显著影响土壤 pH 值、土壤有机质（OM）、总氮（TN）和碱解氮（AN）含量，但对总磷（TP）、总钾（TK）、有效磷（AP）和有效钾（AK）含量无显著影响。在枫杨土壤中，8 种土壤化学性质除 TK 处理和 OM 含量时间效应外，均受到水分处理、时间和处理×时间的显著影响。与未种植土壤相比，CK 处理下枫杨幼苗的生长显著增加了土壤 pH 值和 OM、TN、TP 和 TK 含量，降低了 AN、AP 和 AK 含量，除 CF 处理下的 AK 含量外，增加了土壤化学性质的平均值，且 CK 处理下土壤 pH 值和 TN、AN、TP 和 AP 含量增加，但 OM、TK 和 AK 含量无显著差异。PF 处理下，与未种植土壤相比，土壤 pH 值和 TN、AN、TP 和 AP 含量增加，但 OM、TK 和 AK 含量无显著差异。由于与未种植土壤相比，枫杨土壤中的 TN 和 TP 含量显著增加，因此枫杨幼苗的生长应该是三峡库区河岸带高度动态水文带植被恢复的一个成功候选树种。
