辽河三角洲泥质海岸防护林小气候效益研究

Study on the Benefits of Microclimate of Muddy Coast Protective Forest in Liao River Delta

利用常规观测与梯度观测相结合的方法,对辽河三角洲典型泥质海岸的片状防护林和单片防护林带的风速、土壤温度、光照强度、空气湿度等气象因子进行观测。结果表明:片状林带透风系数为0.26,属于疏透结构,在林带背风区1H-5H(H为树高)范围内风速降低最明显,降低幅度为38.51%～57.25%,10H-20H范围内比较缓和,风速降低8.19%～20.57%,林内风速平均比林外对照降低62.86%;单林带1H-5H风速平均降幅为41.54%～59.53%,10H-20H平均降幅为9.26%～16.14%。林内各层土壤温度比林外低,日平均空气湿度林内比林外高30.6%,日平均光照强度林内比林外降低40.4%。单片、片状林带的有效防风距离为20H;片状海防林带具有改善森林小气候的功能,能够增加林带内空气湿度,降低光照强度,调控土壤温度。

This study was carried out by using the combination of routine observation and gradient observation methods.Wind speed,soil temperature,light intensity,air humidity and other meteorological factors were observed for laminated protective forest and monolithic shelter belt of muddy coast protective forest in Liao River delta.The results showed as follows：laminated forest was sparse structure and its ventilated coefficient was 0.26,leeward areas in the forest 1H-5H（H was tree height） wind speed reduction within the range is the most significant with decrease by 38.51%～57.25%,10H-20H within the scope of a relaxation,wind speed decreased about 8.19%～20.57%,the average wind speed within the forest was 62.86% lower than that outside of the forest.The single forest belt 1H-5H wind speed average range of fall was 41.54%～59.53%,10H-20H average range of fall was 9.26%～16.14%.Soil temperature for inside of the forest was lower than that outside of the forest.Inside of the forest,daily average air humidity was higher than that outside of the forest which was up to 30.6%,for daily light intensity,inside of the forest was 34.7% lower than that outside of the forest.Summaries for this study were showed as follows：the effective windproof distance for laminated protective forest and monolithic shelter belt was 20H.Laminated protective forest had functions of improving microclimate of forest.It can increase air humidity for inside of the forest,reduce light intensity and control soil temperature.