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1.
李翠  王庆海  陈超  温海峰 《生态科学》2019,38(3):133-142
为明确蔡家河湿地土壤种子库特征及其与地上植被和土壤因子的关系, 采用野外调查取样和室内萌发实验相结合的方法, 对芦苇群落, 野艾蒿群落和林下杂草群落3种不同植被类型的土壤种子库密度, 物种组成, 地上植被以及土壤理化性质进行了调查研究。结果表明: 蔡家河湿地3种植被类型的土壤种子库密度分别为(7725±1286) 粒•m-2, (2535±556) 粒•m-2和(5085±984) 粒•m-2; 物种数量分别为36种, 28种和39种。3种植被类型土壤种子库的物种丰富度以及多样性均高于地上植被, 并且3种植被类型间土壤种子库物种组成的相似性高于地上植被, 说明土壤种子库比地上植被具有更高的稳定性。芦苇群落的种子库密度, 物种多样性指数以及土壤种子库和地上植被物种组成的相似性均高于野艾蒿群落和林下杂草群落。土壤含水量与土壤有机质是影响土壤种子库物种组成的主要土壤因子, 在土壤水分以及有机质含量高的芦苇群落中含有大量湿生植物种子, 但在水分和有机质含量低的野艾蒿和林下杂草群落未发现柳叶菜(Epilobium hirsutum)、马先蒿(Pedicularis resupinata)、问荆(Equisetum arvense)等湿生植物的种子。因此, 蔡家河湿地土壤种子库已出现一定程度的退化, 芦苇群落土壤种子库可用作退化湿地植被恢复的种源, 在植被恢复时要满足种子萌发对土壤水分和有机质的需求。  相似文献   

2.
土壤种子库作为地上植被遗传信息库,对植被自然演替更新以及生态修复建设具有重要作用。为探明桂北喀斯特石漠化地区植被自然恢复潜力和恢复策略,该文选取恭城瑶族自治县喀斯特石漠化地区3种典型植物群落为研究对象,分析不同群落的土壤种子库结构、多样性及其对土壤养分特征的响应,以期为该地区石漠化治理和植被恢复提供理论依据。结果表明:(1)共计监测到幼苗3 648株,隶属于33科51属55种,其中1年生和2年生草本幼苗共20种,多年生草本幼苗21种,藤本幼苗5种、灌木幼苗3种、乔木幼苗6种;不同植物群落土壤种子库平均密度为三华李经济林(22 493 grain·m-2)>青冈次生林(1 033 grain·m-2)>金竹灌丛(793 grain·m-2)。(2)土壤种子库植物生活型方面,三华李经济林主要分布1年生恶性杂草,青冈次生林和金竹灌丛则以多年生草本为主,木本植物占比较少;不同植被类型中土壤种子库物种多样性和相似性总体较低,同时与地上群落物种组成的相似性也较低。(3)研究区域的土壤元素存在高氮低磷的现象,其中磷元素为金...  相似文献   

3.
科尔沁沙质草地放牧和围封条件下的土壤种子库   总被引:18,自引:0,他引:18       下载免费PDF全文
该文研究了科尔沁沙质草地在放牧和围封条件下土壤种子库密度、组成及其与地上植被的关系。结果表明:1)放牧草地植物种数22种,围封草地植物种数30种,围封使土壤种子库植物种数增加了36%;2)放牧草地土壤种子库密度为16 149±1 900有效种子数·m-2, 围封草地土壤种子库密度为20 657±3 342有效种子数·m-2,比放牧草地增加了28%。放牧和围封草地种子库组成密度均以一年生植物为主(分别占99%和98%的比例),多年生植物所占的比例很小;3)放牧草地种子库的Shannon-Wiener指数和丰富度指数分别为0.836 3和4.954 9,明显小于围封草地的0.968 2和7.226 0,表明自由放牧导致物种多样性下降;4)放牧和围封草地土壤种子库密度与地上植被密度均存在显著的相关性(p<0.001)。表明了随着土壤种子库密度的增加, 地上植被密度随之增加,放牧草地地上植被密度78%的变异可归结为土壤种子库密度的变异, 而围封草地地上植被密度58%的变异可由土壤种子库密度的变异来解释。  相似文献   

4.
三峡库区消落带回水区水淹初期土壤种子库特征   总被引:6,自引:0,他引:6  
将三峡库区消落带回水区次生灌丛和弃耕地分成水淹区段、未水淹区段和对照样带,通过萌发法对其土壤种子库进行研究.结果表明:两种植被类型的土壤种子库储量存在极显著差异,次生灌丛种子密度为(6991±954)粒·m-2、弃耕地种子密度为(26193±6928)粒·m-2.3种生境中,水淹区段的种子密度最低,未水淹区段最高.随着土层加深,种子库密度逐渐下降.土壤种子库萌发试验出现的物种分属45科97属118种,以一年生和多年生草本植物为主,其中菊科、禾本科、玄参科和十字花科为优势科;个体数量占土壤种子库总储量小于0.01%的物种有34种,占28.8%.两种植被类型的土壤种子库中物种数较接近,物种多样性指数和均匀度较高,但优势物种组成差异很大,生态优势度较低.3种生境中,未水淹区段的生物多样性最高,水淹区段的生态优势度最高;而水淹区段和未水淹区段相似性指数最大.  相似文献   

5.
为了探究三江平原沟渠土壤种子库在湿地植物保护中的作用及其在湿地恢复中的潜力,该文采用幼苗萌发法与样方调查相结合的方法,对三江平原不同开挖年限沟渠的土壤种子库特征及其与地上植被的关系进行了研究。结果表明:沟渠具有较大规模的土壤种子库,边坡种子库显著大于底泥种子库,边坡种子库密度为8 973–25 000 seeds·m–2,底泥种子库密度为506–1 488 seeds·m–2。开挖10年、20年和30年的沟渠土壤种子库共有50种植物萌发,隶属于20科41属。开挖10年、20年和30年的沟渠土壤种子库萌发物种数分别为37种、34种和33种,地上植被物种数分别为25种、33种和22种。土壤种子库和相应地上植被的相似性系数分别为38.7%、35.8%和32.7%。随着植物群落演替的进行,地上植被的Simpson指数、Shannon-Wiener多样性指数和Pielou均匀度指数均逐渐增大。三江平原沟渠土壤种子库和地上植被中保存了大量湿地植物,表明沟渠具有保护植物物种多样性的作用,沟渠土壤种子库具有湿地恢复的潜力。随着沟渠开挖年限增加,沟渠植物群落呈现退化特征,建议对沟渠系统加强管理。  相似文献   

6.
洞庭湖青山垸退耕地不同水位土壤种子库特征   总被引:5,自引:0,他引:5  
研究退耕地土壤种子库的组成特点和分布规律是评价受损湿地生态恢复效应的重要组成部分.本文以洞庭湖典型退田还湖区——青山垸为对象,研究了不同水位及湿地土壤(0~2、2~5和5~10 cm)种子库的大小、物种组成多样性及其与地上植被的关系.结果表明: 青山垸土壤种子库密度、丰富度指数以及地上植被与土壤种子库的相似性系数沿低-中-高水位梯度呈“V”型变化.常淹区种子库密度最高,为(36943±5207)粒·m-2,偶淹区最低,为(18618±6977)粒·m-2,洪淹区居中,为(30572±5329)粒·m-2;地上植被与土壤种子库的相似性系数(Sorensen系数)为常淹区(0.76)>洪淹区(0.53)>偶淹区(0.41).种子库密度、物种多样性指数和物种丰富度指数沿土壤剖面呈递减趋势,但不同水位的递减幅度存在差异.种子库密度、物种丰富度以及地上植被与湿地种子库的相似性系数沿水位梯度呈规律性变化,与其所处的地理位置水文波动和植被的物种生活型组成等密切相关.  相似文献   

7.
青藏高原湿地作为陆地生态系统的重要组成部分,在全球碳循环中发挥着重要作用.以青藏高原东缘尕海湿地植被不同退化程度样地(未退化CK、轻度退化SD、中度退化MD及重度退化HD)为研究对象,通过分析地上植物、凋落物、根系和土壤有机碳,研究湿地植被退化过程中植被-土壤系统有机碳储量变化特征.结果表明: 除HD外,不同退化程度湿地地上植被碳储量为99.58~205.64 g·m-2,根系(0~40 cm)碳储量为56.96~754.37 g·m-2,地上、根系碳储量随退化程度的加剧显著下降,土壤容重随退化程度加剧呈先增加后减少趋势,植被退化湿地各层土壤容重均大于对照样地,而凋落物碳储量为17.29~35.69 g·m-2,CK和MD均显著高于SD;不同退化程度湿地土壤0~40 cm碳储量为7265.06~9604.30 g·m-2,且MD>CK>SD>HD,土壤有机碳储量CK和MD显著高于SD、 HD;植被-土壤系统的碳储量为7265.06~10389.94 g·m-2,各样地大小顺序为CK>MD>SD>HD,有机碳主要储存于土壤中,占湿地总碳贮量的90%以上,说明适度干扰有利于发挥高寒湿地生态系统的碳汇功能.  相似文献   

8.
尾矿废弃地是一种极端的生态系统,其植被恢复的研究将丰富传统的生态学理论。该研究通过野外植被调查与室内萌发实验相结合的方法,探讨了兰坪铅锌矿区植被恢复初期不同群落类型地上植被、土壤种子库及其相互关系。结果显示:(1)与对照群落(云南松林、高山栎灌丛)相比,尾矿区恢复期各群落(早熟禾人工草地、魁蒿群落、马桑灌丛)地上植被及土壤种子库的物种数、物种多样性均较低。(2)植被恢复时间较短的2个群落(魁蒿群落、人工草地)土壤种子库较地上植被物种多样性高。(3)尾矿区恢复期各群落地上植被及土壤种子库的优势种均主要由风播、种子繁殖的植物组成,菊科、禾本科占较大比例,这些植物在尾矿区植被恢复初期起重要作用。(4)尾矿区恢复期各群落土壤种子库与地上植被的物种相似性较高,各群落之间地上植被及土壤种子库的相似性则较低。研究表明,尾矿区恢复初期土壤种子库与地上植被紧密联系,群落改造方式、恢复时间对土壤种子库具有重要影响。  相似文献   

9.
丹江口水库消落带土壤种子库与地上植被和环境的关系   总被引:2,自引:0,他引:2  
以丹江口水库消落带为研究区域,利用层次聚类法将海拔140~145 m区域内37个样地的土壤种子库分为6个组,比较不同组间的种子库物种组成、密度及多样性指数之间的差异;利用相似性指数分析土壤种子库与地上植被的差异;运用主成分分析和多元回归分析土壤种子库密度与地上植被、环境因素的关系.结果表明: 在丹江口水库消落带同海拔区域内,土壤种子库在物种组成上呈明显的异质性,不同组间的种子库密度、多样性指数均存在显著差异;土壤种子库与地上植被的差异较大,而且土壤种子库中的物种数明显少于地上植被中的物种数;土壤种子库密度与地上植被盖度、地上物种数和土壤质地呈显著正相关,而与田间持水量和土壤孔隙度呈显著负相关.  相似文献   

10.
金沙江干热河谷山地植被恢复区土壤种子库和地上植被研究   总被引:10,自引:0,他引:10  
罗辉  王克勤 《生态学报》2006,26(8):2432-2442
土壤种子库在植物种群动态中起着重要作用。土壤种子库可缓解种群的灭绝过程,保存群落中植物种的表现特征,是植被天然更新的物质基础。通过对金沙江干热河谷山地植被恢复区(包括水平阶、自然坡面、沟底)和未恢复区(包括放牧地)的土壤种子库和地上植被的组成、大小及多样性进行比较研究表明,植被恢复区土壤种子库和地上植被的密度、丰富度、多样性及均匀度均大于未恢复区。恢复区地上生物量要远大于未恢复区。水平阶和各类型间的土壤种子库密度与地上植被密度差异显著。土壤种子库中草本植物占很大比例。孔颖草和扭黄茅是土壤种子库和地上植被的两大优势种,两者的个体数量、重要值及生物量最大。土壤种子库和地上植被有较高的相似性,且随着恢复程度的加深,相似性有增高的趋势;土壤种子库密度和地上植被密度之间关系可以用二次和三次曲线拟合。  相似文献   

11.
红壤侵蚀区植被恢复过程中土壤种子库变化特征   总被引:1,自引:0,他引:1  
土壤侵蚀作为一种自然营力和自然干扰形式对土壤种子库的次分布与物种组成具有一定的影响。本研究对典型红壤侵蚀区裸地(Ⅰ号)、马尾松林地(Ⅱ、Ⅲ、Ⅳ号)和次生林(Ⅴ号)等5处不同植被恢复区的土壤种子库物种组成、储量及分布格局进行研究,探究在植被恢复过程中土壤侵蚀对土壤种子库的影响。结果表明: 研究区土壤种子库共统计到21种物种,物种丰富度低,以草本种类为主。各样地土壤种子库密度为56.7~793.3粒·m-2,样地间差异显著,土壤种子库密度随着土壤侵蚀强度加重而明显下降。各样地浅层0~2 cm土壤种子库密度随着上坡-中坡-下坡的变化均呈增加趋势;剧烈侵蚀地和强烈侵蚀地土壤种子库主要分布在5~10 cm深层土壤内,且中上坡0~2 cm土层几乎没有种子。土壤侵蚀使得土壤种子库在土层中的分布呈现深层化,植被恢复后深层种子库积累仍需要较长的时间。  相似文献   

12.
为探究荒漠地区不同植被类型土壤种子库动态与分布规律,揭示不同植被类型群落的植被演替趋势与多样性特征,以腾格里沙漠东南缘胡杨群落、柠条群落、赖草群落和沙蓬群落为对象,采集0~2、2~5、5~10、10~20 cm土层土样,研究土壤种子库特征及其与地上植被的关系。结果表明: 4个植被类型的土壤种子库中共发现13种植物,隶属于3科12属,1、2年生草本植物种子占多数,藜科植物较多;土壤种子库密度较低,呈现柠条群落>赖草群落>胡杨群落>沙蓬群落;种子库密度和植物种类整体随土壤剖面的加深而降低;综合Shannon指数、Simpson指数、Pielou指数和Patrick丰富度指数进行分析,土壤种子库物种多样性呈现胡杨群落>赖草群落>柠条群落>沙蓬群落,柠条群落土壤种子库与地上植被相似性系数最高,沙蓬群落次之,胡杨群落和赖草群落最低。总体上,以胡杨群落为代表的乔木林较为稳定,以沙蓬群落为代表的沙地生态系统最为脆弱。  相似文献   

13.
The density of seeds in soil seed banks and the species composition of both seed banks and aboveground vegetation were examined in naturally restored sites (NRS) and aerially seeded sites (ASS) in the Hunshandak sandlands of northern China. Five sites were naturally restored 1, 2, 4, 8, and 15 years ago and four sites were aerially seeded 1, 2, 5, and 7 years ago. In total, 36 species were recorded in the seed bank and 41 species in the aboveground vegetation for all NRS, whereas the numbers were 17 and 19, respectively, for ASS, indicating that the NRS can support higher diversity of species than the ASS. During the initial 2 years of restoration, introduced alien shrubs by aerial seeding dominated the vegetation of ASS, although there were indigenous pioneer species in the seed bank which failed to establish in the community. In contrast, indigenous species were dominant components in both the seed bank and the vegetation at the NRS. These findings suggest that the establishment of introduced species might have restricted the germination of certain indigenous pioneer species. Seed bank density of NRS significantly increased with time from 459 ± 76 seeds m−2 at NRS2 to 3,351 ± 694 seeds m−2 at NRS15, showing that the seed bank in degraded grassland is large enough to allow natural restoration. It is not always necessary to actively introduce seeds to enhance vegetation diversity.  相似文献   

14.
持久土壤种子库研究综述   总被引:24,自引:3,他引:24  
土壤种子库是指存在于土壤上层凋落物和土壤中全部存活种子,简单地可分为短暂土壤种子库和持久土壤种子库。即使给予理想的萌发条件如季节、温度、湿度等,土壤种子库中也仍有部分种子保持休眠状态,休眠的种子组成了持久土壤种子库。持久土壤种子库具有在承受了空间或时间上不可预测的干扰的植被中发挥繁殖能力的潜势,因此,其在植被承受干扰后的恢复、管理和重建中常常起关键作用。研究持久土壤种子库能丰富生物多样性的内容,同时,可以为深入了解植被更新提供更多的信息。本文从持久土壤种子库的研究方法、分类方法、指示因子、生态意义,以及持久土壤种子库研究中存在的问题和今后的工作进行综述,试图为将来的工作奠定基础。  相似文献   

15.
Luo H  Wang K Q 《农业工程》2006,26(8):2432-2442
Soil seed bank plays an important role in the composition of different plant communities, especially in their conservation. Although soil seed bank, aboveground vegetation and their relationship have been the subject of much recent attention, little is known about the size and species composition of the soil seed bank and about the aboveground vegetation in the semiarid hillslope grasslands. There is limited understanding of how these components interact to determine the importance of seed banks in regeneration. In this study, the size and species composition of a soil seed bank and aboveground vegetation have been assessed in an experiment using 36 vegetation quadrats and 108 soil samples in terrace, slope, gully, and grazing land. This land represents a range of habitats within a hillslope grassland in Jinshajing hot-dry river valley of Yunnan, China. Terrace, slope, and gully represent restored sites and grazing land typifies unrestored sites. Twenty-one taxa in the seed bank were identified with a median and median density of 7 species/m2 and 5498 seeds/m2, respectively, whereas in the aboveground vegetation, 19 species were observed with a median and median density of 6 species/m2 and 1088 plants/m2, respectively. Both seed bank density and aboveground vegetation density among grazing land, gully, slope, and terrace differed significantly. There was an absolutely high proportion of herbaceous species in the seed bank and aboveground vegetation. Gramineae predominated over both seed bank and vegetation. The most frequent seeds and plants were Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv that had the highest individual number, importance value, and biomass. In the seed bank, the seeds of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 50.68% and 33.10% of the total seeds, respectively. In the aboveground vegetation, the individual number of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 55.66% and 29.86% of the total, respectively. The biomass of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for more than 70% of the total, reaching 206.71 g/m2 and 147.76 g/m2, respectively. Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv had the highest importance value of 193.01 and 159.99, respectively. Density, biomass, species richness, species diversity, and evenness were the highest in terrace land, whereas these were lowest in grazing land. Similarities between the seed bank and the aboveground vegetation were moderately high and not very different among slope, gully, and terrace lands, while for grazing land, they tended to increase when the restorative stage progressed. This result contrasts with some other studies where the seed bank contributes very little to the seedling flora and the vegetative growth clearly overwhelms sexual reproduction. The hypothesis about significant functional correlation between soil seed bank density and aboveground vegetation density is conformed. Correlation between soil seed bank density and aboveground vegetation density can be described in quadratic and cubic curves. The strong similarity between the vegetation and the seed bank is attributed to a large proportion of the species Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv., which are seed profusive and whose seeds have a significant viability in the ground. The high density, biomass, species richness, species diversity, and uniformity of the reclaimed site are related to the sufficiency of heat and water supplies for species establishment and growth in the site, which partly reflects the effective efforts for hillslope grassland restoration. It is believed that the efforts for vegetation restoration have altered the microhabitat conditions of the site and have provided a favorable habitat for species to establish and grow.  相似文献   

16.
Hui Luo  Keqin Wang 《生态学报》2006,(8):2432-2442
Soil seed bank plays an important role in the composition of different plant communities, especially in their conservation. Although soil seed bank, aboveground vegetation and their relationship have been the subject of much recent attention, little is known about the size and species composition of the soil seed bank and about the aboveground vegetation in the semiarid hillslope grasslands. There is limited understanding of how these components interact to determine the importance of seed banks in regeneration. In this study, the size and species composition of a soil seed bank and aboveground vegetation have been assessed in an experiment using 36 vegetation quadrats and 108 soil samples in terrace, slope, gully, and grazing land. This land represents a range of habitats within a hillslope grassland in Jinshajing hot-dry river valley of Yunnan, China. Terrace, slope, and gully represent restored sites and grazing land typifies unrestored sites. Twenty-one taxa in the seed bank were identified with a median and median density of 7 species/m2 and 5498 seeds/m2, respectively, whereas in the aboveground vegetation, 19 species were observed with a median and median density of 6 species/m2 and 1088 plants/m2, respectively. Both seed bank density and aboveground vegetation density among grazing land, gully, slope, and terrace differed significantly. There was an absolutely high proportion of herbaceous species in the seed bank and aboveground vegetation. Gramineae predominated over both seed bank and vegetation. The most frequent seeds and plants were Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv that had the highest individual number, importance value, and biomass. In the seed bank, the seeds of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 50.68% and 33.10% of the total seeds, respectively. In the aboveground vegetation, the individual number of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 55.66% and 29.86% of the total, respectively. The biomass of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for more than 70% of the total, reaching 206.71 g/m2 and 147.76 g/m2, respectively. Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv had the highest importance value of 193.01 and 159.99, respectively. Density, biomass, species richness, species diversity, and evenness were the highest in terrace land, whereas these were lowest in grazing land. Similarities between the seed bank and the aboveground vegetation were moderately high and not very different among slope, gully, and terrace lands, while for grazing land, they tended to increase when the restorative stage progressed. This result contrasts with some other studies where the seed bank contributes very little to the seedling flora and the vegetative growth clearly overwhelms sexual reproduction. The hypothesis about significant functional correlation between soil seed bank density and aboveground vegetation density is conformed. Correlation between soil seed bank density and aboveground vegetation density can be described in quadratic and cubic curves. The strong similarity between the vegetation and the seed bank is attributed to a large proportion of the species Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv., which are seed profusive and whose seeds have a significant viability in the ground. The high density, biomass, species richness, species diversity, and uniformity of the reclaimed site are related to the sufficiency of heat and water supplies for species establishment and growth in the site, which partly reflects the effective efforts for hillslope grassland restoration. It is believed that the efforts for vegetation restoration have altered the microhabitat conditions of the site and have provided a favorable habitat for species to establish and grow.  相似文献   

17.
青藏高原东缘封育和退化高寒草甸种子库差异   总被引:1,自引:0,他引:1  
采用幼苗萌发法研究了青藏高原东部高寒草甸封育和退化地区土壤种子库的差异.结果表明:(1)两个样地总共有10161株幼苗萌发,分属55个物种,23个科.封育样地多年生植物比例高于退化样地,禾草和单子叶植物比例在两个样地间差异不大.(2)退化样地土壤种子库种子密度((6105±1530) m-2)显著高于封育样地((3883±798) m-2),而物种丰富度差异不显著.所研究区域拥有较为丰富的种子库资源,退化地区资源更丰富,说明恢复不存在种子限制问题,土壤种子库可以成为植被恢复的潜在资源.(3)种子密度和物种丰富度在垂直分层上差异显著,且随着深度的增加而显著减小.(4)用Srensen coefficient指数计算出土壤种子库和地上植被之间的相似性在整体上较低,封育样地(45.3%)略高于退化样地(40.4%),两个样地地上植被之间的相似性为50%,而种子库之间相似性高达84.6%,说明种子库起到一个"缓冲器"的作用.(5)Shannon-Wiener多样性指数分析显示,无论在地上植被或种子库中,物种多样性都是封育样地显著高于退化样地.过度放牧不仅导致地上植被的生物多样性丧失,而且使种子库中的物种多样性降低,而封育管理可以维持地上植被和种子库中的物种多样性.  相似文献   

18.
研究片段化森林中土壤呼吸速率的格局对进一步揭示陆地生态系统碳循环具有重要意义。本研究以千岛湖人工陆桥岛屿系统不同生境(岛屿与大陆,岛屿边缘与岛屿内部)为对象,分析了土壤呼吸速率的季节动态变化规律及其与土壤理化因子的关系。结果表明: 1)土壤呼吸速率在不同季节差异显著。夏季(3.74 μmol·m-2·s-1)>秋季(2.30 μmol·m-2·s-1)>春季(1.82 μmol·m-2·s-1)>冬季(1.40 μmol·m-2·s-1)。2)森林片段化对土壤呼吸速率产生显著影响,岛屿土壤呼吸速率(2.37 μmol·m-2·s-1)显著高于大陆(2.08 μmol·m-2·s-1);岛屿边缘土壤呼吸速率(2.46 μmol·m-2·s-1)显著高于岛屿内部(2.03 μmol·m-2·s-1)。3)土壤温度显著促进了土壤呼吸速率,并作为主要因子解释了56.1%的变化。4)土壤呼吸速率与土壤全碳、铵态氮含量和地表植被覆盖率呈显著正相关。土壤全碳和铵态氮含量在岛屿边缘显著高于岛屿内部。综上,森林片段化促进了土壤呼吸速率,而土壤理化因子的变化是其主要原因。  相似文献   

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