采伐对森林土壤呼吸影响的研究进展

土壤呼吸是大气二氧化碳(CO₂)重要的来源，采伐作为森林经营的常规活动之一，是影响森林土壤呼吸的重要人为干扰措施。开展有关采伐对森林土壤呼吸影响的研究对更好地理解森林碳循环和应对全球气候变化具有重要的科学意义和应用价值。本研究将采伐分为2类:皆伐和部分采伐(择伐、渐伐、间伐和更新采伐等)。分别综述了皆伐和部分采伐对土壤呼吸影响的代表性研究成果，讨论了皆伐和部分采伐对土壤呼吸的主要影响机制，总结了当前采伐对森林土壤呼吸及其组分与土壤温度敏感性(Q₁₀)的影响并对未来研究提出展望。目前采伐对土壤呼吸的研究主要集中于:①采伐强度对土壤呼吸影响的方向和幅度；②皆伐或部分采伐后土壤呼吸随时间变化的动态特征及受土壤温度等环境因子的影响；③皆伐或部分采伐对土壤呼吸组分的影响；④皆伐或部分采伐对Q₁₀的影响；⑤皆伐或部分采伐对土壤呼吸的影响机制。主要结论为:①因采伐强度、采伐措施、采伐剩余物的处理、气候类型、森林类型和植被恢复时间的不同，采伐的影响效果呈现不同的变化规律；②采伐往往导致土壤自养呼吸减少，异养呼吸增加，土壤总呼吸表现为两者相抵的程度，这种影响会随植被恢复程度的提高而减小；③采伐后短期内Q₁₀有不同的变化规律，长期往往会下降。未来关于采伐对森林土壤呼吸影响的研究应集中于土壤呼吸组分及其温度敏感性对采伐的响应，同时应结合不同强度采伐、不同植被恢复阶段、其他营林措施和大气CO₂浓度上升等全球变化因子，探讨采伐对区域土壤呼吸及组分的影响，更好地理解采伐对森林生态系统碳循环的影响机制。表2参89

Research progress on effects of cutting on forest soil respiration

Logging, as one of the routine forest management activities, is an important human interference measure affecting forest soil respiration, an important source of atmospheric CO₂. Therefore, research on the effects of logging on forest soil respiration has important scientific significance and application value for better understanding forest carbon cycle and coping with global climate change. This paper, with logging divided into two types: clear cutting and partial cutting (further classified as selective cutting, gradual cutting, thinning and regeneration cutting, etc.), is aimed to conduct a review of research advances on the effects of clear cutting and partial cutting on soil respiration, a discussion of the main mechanisms of clear cutting and partial cutting on soil respiration as well as a summary of the effects of current cutting on forest soil respiration and its components and soil temperature sensitivity (Q₁₀) with future research prospects put forward. Results showed that the researches on soil respiration are mainly focused on the following aspects: (1) the direction and extent of the effect of clear cutting or cutting intensity on soil respiration; (2) the dynamic characteristics of soil respiration with time and environmental factors such as soil temperature after clear cutting or partial cutting; (3) effects of clear cutting or partial cutting on soil respiration components; (4) the effect of clear cutting or partial cutting on Q₁₀ and (5) the effect mechanism of clear cutting or partial cutting on soil respiration. The main conclusions are as follows: (1) the effect of cutting varies with different cutting intensity, cutting measures, treatment of cutting residues, climate types, forest types and vegetation restoration time; (2) the results showed that the soil autotrophic respiration usually decreased and heterotrophic respiration usually increased after logging, and the total soil respiration showed that autotrophic respiration and heterotrophic respiration offset each other, and this effect would decrease with the increase of vegetation restoration. It is proposed that further efforts should be focused on the impact of different intensity of harvesting, different vegetation restoration stages, other forest management measures and rising atmospheric CO₂ concentration on regional soil respiration and components, so as to better understand the impact mechanism of harvesting on forest ecosystem carbon cycle. [Ch, 2 tab. 89 ref.]