CAJ | 학술논문

城市树木与森林作为城市生态系统的重要组成部分,充分发挥其生态环境服务、景观美化和休闲娱乐等功能得到了社会各界越来越广泛的重视.配置合理的城市树木与森林,建设节水型城市森林是水资源短缺地区城市生态建设必须重视的问题之一.以大连市劳动公园4种主要乔木树种雪松(Cedrus deodara)、榉树(Zelkova serrata)、丝棉木(Euonymus bungeanus)及水杉(Metasequoia glyptostroboides)为研究对象,应用TDP(Thermal Dissipation Probe)技术分别对每个树种3个径阶的单株树木蒸腾耗水进行了研究,并测定同期气候环境因子及0～25cm,25～50cm,50～75cm,75～100cm土壤含水量的动态变化.研究结果表明:不同树种生长季内蒸腾耗水具有明显的昼夜变化规律,3个径阶雪松夜间蒸腾量占全天的6.3%～33.9%;榉树占 12.4%～30.8%;丝棉木占6.5%～27.6%;水杉占6.0%～21.1%.受气候环境因子、土壤含水量以及树木生长节律的影响,各树种日蒸腾耗水量从9月以后表现为递减的变化.晴天、雨天与阴天3种典型天气条件下树木液流速率表现出不同的变化特征:晴天液流速率曲线较平缓且峰值范围较宽,液流开始升高时间最早,开始降低时间最晚,液流通量最大;雨天,峰值陡且窄,液流开始升高时间最晚,开始降低时间最早,液流通量最小;阴天表现居中.对各树种在整个生长季内蒸腾量从大到小的排序,径阶为10cm的树种为:丝棉木>榉树;径阶为14cm的树种为:丝棉木>榉树>雪松>水杉;径阶为18cm的树种为:雪松>丝棉木>榉树>水杉;径阶为24cm的树种为:雪松>水杉.
성시수목여삼림작위성시생태계통적중요조성부분,충분발휘기생태배경복무、경관미화화휴한오악등공능득도료사회각계월래월엄범적중시.배치합리적성시수목여삼림,건설절수형성시삼림시수자원단결지구성시생태건설필수중시적문제지일.이대련시노동공완4충주요교목수충설송(Cedrus deodara)、거수(Zelkova serrata)、사면목(Euonymus bungeanus)급수삼(Metasequoia glyptostroboides)위연구대상,응용TDP(Thermal Dissipation Probe)기술분별대매개수충3개경계적단주수목증등모수진행료연구,병측정동기기후배경인자급0～25cm,25～50cm,50～75cm,75～100cm토양함수량적동태변화.연구결과표명:불동수충생장계내증등모수구유명현적주야변화규률,3개경계설송야간증등량점전천적6.3%～33.9%;거수점 12.4%～30.8%;사면목점6.5%～27.6%;수삼점6.0%～21.1%.수기후배경인자、토양함수량이급수목생장절률적영향,각수충일증등모수량종9월이후표현위체감적변화.청천、우천여음천3충전형천기조건하수목액류속솔표현출불동적변화특정:청천액류속솔곡선교평완차봉치범위교관,액류개시승고시간최조,개시강저시간최만,액류통량최대;우천,봉치두차착,액류개시승고시간최만,개시강저시간최조,액류통량최소;음천표현거중.대각수충재정개생장계내증등량종대도소적배서,경계위10cm적수충위:사면목>거수;경계위14cm적수충위:사면목>거수>설송>수삼;경계위18cm적수충위:설송>사면목>거수>수삼;경계위24cm적수충위:설송>수삼.
Urban forests play a significant role in urban development because it provides valuable ecological and environmental services, landscape integrity, and recreation opportunities for urban residents. However, water saving approaches for urban forest development must be adopted in the cities that are facing water resources shortage. Many studies suggested that forests have much higher water demand than shorter plants. Therefore, it is critically important to select water-saving trees in urban forestry practices in order to achieve the sustainable urban greening and landscaping. We selected four major urban tree species including Cedrus deodara,Zelkova serrata,Euonymus bungeanus,Metasequoia glyptostroboides.to quantify whole tree water use in the Labor Park of Dalian City, Liaoning Province, China. Thermal Dissipation Probes were deployed to monitor the sap-fluxes continuously for 12 trees, three DBH classes of each species, from June through October in 2008. Climatic variables and soil moisture at the depth of 0-25cm, 25-50cm, 50-75cm, and 75-100cm were also measured by an automatic weather station and EMS70 soil moisture probes at the same time, respectively. The remarkable diurnal-nocturnal variation of sapflux for different species was observed during the growing season and the nocturnal water loss accounted for a certain proportion of the total transpiration: 6.3%-33.9% for Cedrus deodara, 12.4%-30.8% for Zelkova serrata, 6.5%-27.6% for Euonymus bungeanus, and 6.0%-21.1% for Metasequoia glyptostroboides across three diameter classes. Due to compounding impact of climatic factors, soil moisture regime, and the tree growth patterns, the diurnal transpiration rate declined since September for all trees. Contrasting characteristics of daily sapflux pattern were found under three typical weather conditions. Sapflux curves of clear sunny days were relatively flat with wide range of peaks, showing an earliest start time of sap-flow, an latest declining time with the highest daily sap-flux volume. Sapflux curves of raining days showed steep and narrow peaks accompanied by a latest sap-flow start time, and earliest declining time along with lowest sap-flux volume. The performance for cloudy days stood in between. The whole tree water use ranking from high to low during the entire growing season was as follows: Euonymus bungeanus> Zelkova serrata within the 10 cm diameter class, Euonymus bungeanus> Zelkova serrata> Cedrus deodara > Metasequoia glyptostroboides within the 14 cm diameter class, Cedrus deodara >Euonymus bungeanus> Zelkova serrata > Metasequoia glyptostroboides within the 18 cm diameter class, and Cedrus deodara > Metasequoia glyptostroboides within the 24 cm diameter class.