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1.
1引言物种多样性是生态系统的重要特征并维持系统的功能运行,生物多样性与生态系统抵御逆境和抗干扰能力有关,多样性的提高会增强系统的稳定性及生态服务功能[4,5,13,14,24,25,32,36].林下植被在维持森林物种多样性、立地指示、水土保持、促进人工林养分循环、维护林地地力和揭示植被演替特征等方面具有不可忽视的作用[3,12,19,20,35].马尾松(Pinus massoniana)是我国南亚热带地区的主要针叶林之一,由于人为活动(造林、抚育、樵采等)对人工林下物种丰富度干扰很大,造成了森林的严重退化[33,34,37],不利于人工林的可持续发展.南亚热带植被的…  相似文献   

2.
人类活动对生态系统的影响是当今生态学的研究热点之一, 但对在退化生态系统上进行人工造林对地带性植被群落学特征的影响研究尚较欠缺。本文根据组成群落的植物生态学特征能对其生态环境做出准确的反应这一规则, 通过样地调查法分析了林龄为12年的西南桦(Betula alnoides)人工群落的区系组成和基本的群落学特征, 并与当地的地带性植被——山地雨林的区系组成和群落学特征进行了比较, 从而探讨人工造林对当地天然生态系统的影响。结果发现, 与天然群落相比, 人类活动(人工种植西南桦林)对生态系统的植物物种的生活型谱、物种叶型谱、区系成分、物种多样性等方面的群落学特征影响不大;即使在这些方面有或多或少的差异, 可能也是小环境的异质性造成的。但是人工种植西南桦林对群落的季相外貌、群落的结构、物种组成、物种丰富度以及生物量等方面有较大的影响。进行综合分析后得出结论: 虽然人工造林可以缩短植被自然恢复的时间以及具有显著的经济价值, 但与地带性植被相比, 还是有较大的生态学差异。建议为了当地经济的发展, 有必要适当发展一定面积的人工林, 但规模应适度。  相似文献   

3.
西南桦人工林与山地雨林的群落学特征比较   总被引:7,自引:0,他引:7  
人类活动对生态系统的影响是当今生态学的研究热点之一,但对在退化生态系统上进行人工造林对地带性植被群落学特征的影响研究尚较欠缺。本文根据组成群落的植物生态学特征能对其生态环境做出准确的反应这一规则,通过样地调查法分析了林龄为12年的西南桦(Betula alnoides)人工群落的区系组成和基本的群落学特征,并与当地的地带性植被——山地雨林的区系组成和群落学特征进行了比较,从而探讨人工造林对当地天然生态系统的影响。结果发现,与天然群落相比,人类活动(人工种植西南桦林)对生态系统的植物物种的生活型谱、物种叶型谱、区系成分、物种多样性等方面的群落学特征影响不大;即使在这些方面有或多或少的差异,可能也是小环境的异质性造成的。但是人工种植西南桦林对群落的季相外貌、群落的结构、物种组成、物种丰富度以及生物量等方面有较大的影响。进行综合分析后得出结论:虽然人工造林可以缩短植被自然恢复的时间以及具有显著的经济价值,但与地带性植被相比,还是有较大的生态学差异。建议为了当地经济的发展,有必要适当发展一定面积的人工林,但规模应适度。  相似文献   

4.
红树林湿地恢复技术的研究进展   总被引:11,自引:0,他引:11  
本文从红树林育苗造林技术、次生林改造技术和红树植物引种试种与种源选择的研究等方面试述红树林湿地恢复技术的研究进展,并针对我国的目前现状,提出今后亟待加强研究的如下几个方面:加强红树植物引种扩种,恢复植被,提高红树林生态工程质量的原理研究;监测外来引进种对我国红树林湿地的生态影响;研究半红树植物在沿海防护林体系工程建设中的作用;加强红树植物对潮汐水位适应能力的研究;开展红树人工林生态恢复过程中的综合定位观测等。  相似文献   

5.
滇池流域人工林群落结构及水土保持效益   总被引:1,自引:0,他引:1  
以滇池流域5种主要人工林(柏木林、桉树林、银荆林、华山松林和云南松林)为研究对象,通过样方调查,分析群落结构特征,并构建了由植被、枯落物、土壤、地形4个因子组成的水土保持功能评价指标体系,在对所选取的8个指标进行标准化、确定权重的基础上,运用理想点综合评价方法评价其水土保持效益.结果表明:各人工林群落优势种重要值(Ⅳ)分别为:柏木89.69、桉树74.27、银荆96.35、华山松84.93、云南松65.65.桉树林、云南松林分层物种多样性表现为灌木层>草本层>乔木层,柏木林、银荆林和华山松林分层物种多样性表现为草本层>灌木层>乔木层.云南松林的群落总体物种多样性最高,华山松林和桉树林次之,柏木林较低,银荆林最低.各人工林水土保持效益依次为:云南松林>华山松林>柏木林>桉树林>银荆林,表明乡土树种作为水土保持林具有一定的优势.不同人工林在物种多样性及水土保持效益等方面存在明显差异,应根据立地条件选择适宜的造林树种及搭配方式,提升其生态功能,控制水土流失.  相似文献   

6.
从植物群落学原理谈黄土高原植被建造的几个问题   总被引:40,自引:6,他引:34  
依据植被地带性分布规律及植物群落结构原理,对黄土高原大面积建造林草植被的实践和学术上存在的有关问题进行了分析讨论。认为对造林而言应强调适地适林,“适地适树”的提法有不确切性,因为很多适地适树的树种用作主要造林树种则不适宜,指出应选择相应地带植被优势种用于造林种草,辅以伴生种,建立不同类型的复层混交植被,森林带,森林草原带,草原带分别以针阔混交,乔灌草混交,稀树灌草丛模式为主。从人工林草地土壤水分动态看,“草灌先行”的造林途径是不可行的。  相似文献   

7.
顾峰雪  陶波  温学发  于贵瑞  李克让 《生态学报》2010,30(23):6598-6605
随着造林活动的开展,准确评估人工林的碳储量和固碳能力,对于准确估算全球和区域碳平衡具有重要意义。基于生态系统机理模型为分析和预测人工林生态系统碳储量和碳汇功能的动态特征提供了重要手段。CEVSA2模型是在CEVSA模型的基础上,改进了碳水循环关键过程的定量表达方法而发展的新版本。基于改进后的CEVSA2模型,模拟分析了亚热带红壤丘陵区人工林自造林以来生态系统碳储量和碳通量的变化特征。模拟结果表明,造林后,植被碳持续增加,研究时段内平均每年的增长速率为22%。土壤碳储量在造林后最初的7-8a间是逐渐下降的,而后逐渐升高,约15a后土壤碳增加到初始水平,随后土壤碳继续增加。生态系统的总碳储量也表现为先降低后增加,造林4a后,总碳储量由降低转为增加趋势,6a后,总碳储量即超过造林当年的总碳储量。造林后,总初级生产力和净初级生产力逐渐升高,而总呼吸则先降低后升高,呼吸组分中自养呼吸所占比例逐渐升高而异养呼吸逐渐下降。人工林在造林初期表现为一个碳源,随着人工林的生长,碳汇功能逐渐增强。由此可见,造林初期,生态系统碳储量下降,生态系统向大气释放碳,随着人工林的生长,生态系统转变为一个碳汇,植被碳、土壤碳和总碳储量均显著增加。  相似文献   

8.
桉树人工林物种多样性变化特征   总被引:9,自引:1,他引:8  
刘平  秦晶  刘建昌  王华锋  王效科 《生态学报》2011,31(8):2227-2235
为了探讨大面积人工种植桉树林中植被类型和物种多样性的变化,以云南省西南部56.3万亩桉树人工林及其周围环境为研究区域,通过群落学调查,运用重要值、多样性、丰富度、均匀度等指标,统计分析桉树人工林、次生季风常绿阔叶林(以下简称次生林)和撂荒地3种不同植被类型的结构、种类组成和物种多样性。结果表明,桉树人工林中植被经过一定时间的演替会达到一定的丰富度,植物物种数和个体总数呈现出复杂性变化的特点,但规律性并不明显。桉树林样地中出现植物135种,隶属73科97属,草本层为最发达的一层;次生林样地中出现植物270种,隶属146科189属,乔木层为最发达层;撂荒地样地中出现植物105种,隶属74科104属,无乔木层。以样点9为例,类似立地因子的桉树林乔木层、灌木层和草本层的重要值Iv与其他2种植被类型相比差异较为明显。统计分析显示,桉树林多样性指数D值和H值、均匀度指数J值显著低于次生林(p<0.05),在海拔1700 m以下显著低于撂荒地(p <0.05),而1700m以上略高于撂荒地。桉树(Eucalyptus spp. )对植物群落多样性的影响与造林前的土地利用类型有关,在轮歇的撂荒地和低效灌木林地上发展桉树林不仅可以提供木材或纸浆材资源,而且还能够丰富植被结构和增加植物群落多样性。  相似文献   

9.
沙地樟子松人工林营林技术研究进展   总被引:16,自引:0,他引:16  
人工林能否实现可持续经营与其营林技术息息相关。中国造林与世界各地一样,纯林多.树种单调.发生的问题也相似。自20世纪90年代以来,沙地樟子松人工林出现了不同程度的衰退现象.但目前在我国北方干旱、半干旱风沙地区樟子松人工造林仍在大面积推广.因此,为实现樟子松人工林的可持续经营,总结并探讨樟子松人工林营林技术显得尤为重要。本文在广泛收集国内外有关樟子松研究的基础上,综述了近20年来有关樟子松在造林和经营方面的研究进展,主要包括造成樟子松沙地造林成活率和保存率低的原因、提高造林成活率的技术方法、种子的生产、密度管理、栽培模式以及问伐与更新等,提出了在沙地樟子松造林与经营研究中亟待解决的一些问题和建议.对今后樟子松沙地人工林衰退研究及经营实践具有参考价值。  相似文献   

10.
森林生态系统是陆地生态系统中重要的组成部分, 枯落物又是森林结构中重要的一环, 具有涵养水源、拦蓄降水、减少径流、维持土壤湿度、防止土壤水分散失和土壤溅蚀等重要的水文生态功能。研究影响枯落物持水特性的因素, 揭示各因素与枯落物持水特性之间的关系, 对研究森林的水土保持能力, 合理规划和利用水资源方面具有重要的意义。笔者了影响枯落物持水特性的重要因素(如森林类型、林分特征和成土因素等), 探讨了各因素与枯落物持水特性之间的关系及影响程度, 以期为人工林立地环境的筛选、造林树种的配置、以及天然林与人工林的营林措施选择方面提供合理的建议和参考。  相似文献   

11.
黄土高原水土保持林对土壤水分的影响   总被引:8,自引:0,他引:8  
张建军  李慧敏  徐佳佳 《生态学报》2011,31(23):7056-7066
黄土高原植被恢复的限制因素主要是土壤水分,植被与土壤水分关系的研究对黄土高原植被恢复具有重要意义.2008年7月1日至2009年10月31日间采用EnviroSMART土壤水分定位监测系统以每30min监测1次的频度,对晋西黄土区刺槐人工林地、油松人工林地、次生林地的土壤水分变化进行了研究.研究得出:次生林地0-150 cm土层中平均蓄水量为331.95mm,刺槐人工林地为233.85 mm,有整地措施的油松人工林地为314.85mm,刺槐人工林比次生林多消耗的98.10mm土壤水分主要来源于80 cm以下土层.次生林主要消耗0-80 cm土层的水分,而人工林不但对0-80 cm土层水分的消耗量大于次生林,对深层土壤的消耗也较次生林大,这将有可能导致人工林地深层土壤的“干化”.在土壤水分减少期(11-1月)刺槐人工林土壤水分的日均损耗量为0.86mm、油松人工林为0.82 mm、次生林为0.84 mm.土壤水分缓慢恢复期(2-5月)刺槐人工林地土壤水分的恢复速度0.90mm/d,油松人工林地为0.53 mm/d、次生林地为0.79 mm/d.土壤水分剧烈变化期(5-10月)刺槐人工林地土壤水分含量的极差为95.71mm,油松人工林地为179.1mm,次生林地为72.03mm.在干旱少雨的黄土高原进行植被恢复时,应多采取封山育林等方式,依靠自然力量形成能够与当地土壤水资源相协调的次生林,是防止人工植被过度耗水形成“干化层”、保障水土保持植被持续发挥生态服务功能的关键.  相似文献   

12.
Tropical plantations are rapidly expanding as a source of industrial wood. In Indonesia, such large-scale industrial plantations are generally made of large mono-specific blocks interspersed with natural forest remnants. The extent and biodiversity value of these remnants vary as laws and regulations on their design and management are either unclear, without solid scientific basis or left to the interpretation of private companies responsible for the plantations. Our study area comprises of three Acacia mangium plantations, which have on average 18% of their total area set aside from production and conserved as natural forests. These remnant natural forests may, if appropriately designed and managed, be used to mitigate the negative impact of plantations on biodiversity by providing some degree of connectivity with and between remaining natural forest patches (such as the Tesso Nilo conservation area). We sampled natural vegetation in one and primate diversity in all three plantation sector and examined patterns of primate species richness and abundance with relation to spatial arrangement and dimensions of conservation area, which has been set aside from plantation production. We demonstrate unambiguously the critical importance of a well-connected network of natural forest corridors in the plantation landscape to maintain primates and discuss the potential biodiversity value of natural forest remnants in broad-scale industrial landscapes.  相似文献   

13.
The continued decline of natural forests globally has increased interest in the potential of planted forests to support biodiversity. Here, we examine the potential conservation benefits of plantation forests from an Irish perspective, a country where remaining natural forests are fragmented and degraded, and the majority of the forest area is comprised of non-native Sitka spruce (Picea sitchensis (Bong.) Carr.) and Norway spruce (Picea abies (L.) Karst.) plantations. We examine the true value of Irish plantation forests to native biodiversity, relative to remaining natural forest fragments, and to prior and alternative land use to afforestation. We find that plantation forests provide a suitable surrogate habitat primarily for generalist species, as well as providing habitat for certain species of conservation concern. However, we find that plantation forests provide poor habitat for native forest specialists, and examine potential management strategies which may be employed to improve habitat provision services for this group.  相似文献   

14.
防护林阶段定向经营研究I.理论基础   总被引:3,自引:0,他引:3  
姜凤岐  朱教君 《应用生态学报》2002,13(10):1352-1355
基于多年防护林经营研究与实践,在分析防护林经营目的的基础上,提出了防护林阶段定向经营理论基础,以防护林的防护成熟为核心,将防护林经营阶段划分为成熟前期,即从栽植后形成相对稳定的幼林到初始防护成熟龄;防护成熟期,防护成熟状态持续的时期,即从初始防护成熟龄到终止防护成熟龄;更新期,林木接近自然成熟开始更新直到更新结束并形成相对稳定的幼林,防护林经营的定向是指在任何经营阶段内,一切经营技术与措施都是为了使防护林向着成熟的状态发展,即防护成熟是防护林经营的方向,是最终目的,为尽量维持防护林的成熟状态并使防护效益不间断,针对发育正常与低质衰退的林分,在各个经营阶段内采取相应的系列经营管理与改造措施。  相似文献   

15.
南亚热带退化植被重建中土壤动物群落变化   总被引:16,自引:0,他引:16  
在广东省中部的鹤山市鹤山丘陵综合试验场,分别在草坡、松林、荷木混交林(荷混林)、马占相思林(马占林)和豆科混交林(豆混林)选取5块样地,分别代表5种处理方式(重建植被类型)。在2003~2004年的4个不同季度内分3层取土样,利用Tullgren干漏斗法采集土壤动物,并分析土壤动物群落个体数量、类群丰度和DG指数的变化。研究结果表明,季节、植被类型和土层深度对土壤动物群落的各项指标都有极显著影响(P<0·01,three-way-ANOVA):土壤动物群落指标,在秋季显著为高(P<0·05,DMRT),而夏季显著为低(P<0·05,DMRT);随土层加深而逐级显著降低;不同植被类型比较,豆混林>马占林>荷混林、松林和草坡。此外,植被类型还与季节和土层间存在显著的交互作用:土壤动物群落各项指标秋季最高,不同植被类型间的差异也最大;而土壤动物群落各项指标较高的植被类型内不同土层间的差异也较大。由此推测,对退化生态系统进行人工改造是有积极意义的,而不同植被类型间土壤动物的差异可能与凋落物的数量与质量密切相关。  相似文献   

16.
We investigated seasonal fluctuation patterns in species and individuals of adult butterflies and flowering plants providing nectar in a semi-natural grassland in central Japan. We considered their interrelationships and implications for conservation. The semi-natural grassland included different vegetation structures and management regimes, including: (1) firebreaks where the grass was mowed and removed, (2) plantation areas that were mowed, (3) unpaved roads with mowed banks, (4) abandoned grassland, (5) scattered scrub forest, and (6) the surrounding forest. The sites with management (e.g., firebreaks), plantations and banks of the unpaved road sustained a larger number of butterflies and flowers than sites without management, such as the abandoned grassland, scrub forest and surrounding forest. The number of butterflies increased in the firebreak in June and at all sites in August and September. The firebreak sustained flowers in the spring, and the plantation area and banks of the unpaved road sustained flowers primarily in August and September, which was correlated with the distribution of butterflies. The different treatments such as mowing or mowing with removal of grass induced different numbers of flowers of each species affecting the habitat of adult butterflies through a season. On the other hand, the shrub tree species composing the scrub forest were host plants for the larvae of certain butterfly species. Our results suggest that heterogeneous environments with different human management or different vegetation structure or both could support habitat for various butterfly species, depending on the season and the seral stage.  相似文献   

17.
亚热带不同树种土壤水源涵养功能   总被引:1,自引:0,他引:1  
亚热带地区由于大面积的砍伐使天然林被人工林所代替,对森林土壤水源涵养功能造成了很大影响。树种可以通过自身特性来改变土壤物理结构进而影响土壤持水能力,因此合理选择树种对区域水源涵养具有重要意义。然而,立地条件的差异往往会对实验结果产生影响。为减少立地条件的差异,2012年2月在土壤发育和经营历史相同的林地上建立了中亚热带常见树种同质园。2019年8月测定了种植12个树种后不同土层(0—10、10—20、20—30、30—40 cm和40—50 cm)的土壤容重、含水量、总/毛管/非毛管孔隙度、最大/毛管/非毛管持水量和蓄水量。结果表明,种植不同树种7年后,土壤容重、含水量、总/毛管/非毛管孔隙度、最大/毛管/非毛管持水量和蓄水量均在表层(0—20 cm)土壤中差异显著,而在深层(20—50 cm)土壤中差异不显著。土壤孔隙度、持水量和蓄水量均与土壤容重呈显著负相关关系,而与土壤含水量呈显著正相关关系。与其他树种相比,种植鹅掌楸、枫香和全缘叶栾树等落叶阔叶树种可在较短时间内增加土壤孔隙度,提高土壤持水量和蓄水量。因此,在亚热带人工林经营管理中,可在杉木、马尾松纯林中适当引入鹅掌楸、枫香和全缘叶栾树等落叶阔叶树种,提升亚热带森林土壤水源涵养功能。  相似文献   

18.
Industrial timber plantations severely impact biodiversity in Southeast Asia. Forest fragments survive within plantations, but their conservation value in highly deforested landscapes in Southeast Asia is poorly understood. In this study, we compared bird assemblages in acacia plantations and fragmented forests in South Sumatra to evaluate each habitat’s potential conservation value. To clarify the impact of habitat change, we also analyzed the response of feeding guild composition. Five habitat types were studied: large logged forest (LLF), burnt logged forest (BLF), remnant logged forest (RLF), 4-year-old acacia plantation (AP4), and 1-year-old acacia plantation (AP1). Estimated species richness (Chao 2) was highest in LLF then AP4 and BLF, while AP1 and RLF had lower estimated species richness. Community composition was roughly divided into two groups by non-metric multidimensional scaling ordination: acacia plantation and logged forest. Sallying substrate-gleaning insectivores, such as drongos, broadbills, and some flycatchers, were restricted to LLF, whereas acacia plantation hosted many terrestrial frugivores, such as doves. Although fragmented forests in our study site lacked several common tropical forest species, these fragments provide an important habitat for some sallying and terrestrial insectivores. A network of small riparian remnant forests could be a complementary habitat for some species, while the conservation value of burnt forest might be low. In conclusion, the highly fragmented forests in plantations are suboptimal habitats for birds but are still very important, because large primary forest blocks have been nearly lost in the surrounding landscape.  相似文献   

19.
Short‐rotation woody cropping (SRWC) refers to silvicultural systems designed to produce woody biomass using short harvest cycles (1–15 years), intensive silvicultural techniques, high‐yielding varieties, and often coppice regeneration. Recent emphasis on alternatives to fossil fuels has spurred interest in producing SRWC on privately owned and intensively managed forests of North America. We examined potential bird and small mammal response at the stand level to conversion of existing, intensively managed forests to SRWCs using meta‐analysis of existing studies. We found 257 effect sizes for birds (243 effect sizes) and mammals (14 effect sizes) from 8 studies involving Populus spp. plantations. Diversity and abundance of bird guilds were lower on short‐rotation plantations compared with reference woodlands, while abundance of individual bird species was more variable and not consistently higher or lower on SRWC plantations. Shrub‐associated birds were more abundant on SRWC plantations, but forest‐associated and cavity‐nesting birds were less abundant. Effects on birds appeared to decrease with age of the SRWC plantation, but plantation age was also confounded with variation in the type of reference forest used for comparison. Both guilds and species of mammals were less abundant on SRWC plantations. These conclusions are tentative because none of these studies directly compared SRWC plantations to intensively managed forests. Plantations of SRWCs could contribute to overall landscape diversity in forest‐dominated landscapes by providing shrubby habitat structure for nonforest species. However, extensive conversion of mature or intensively managed forests to SRWC would likely decrease overall diversity, especially if they replace habitat types of high conservation value.  相似文献   

20.
榆树(Ulmus pumila)疏林是浑善达克沙地的地带性隐域植被, 小叶杨(Populus simonii)是该区域主要的防风固沙造林树种。该文通过测定两种森林生态系统乔木层(叶、枝、干、根)、草本层(地上植被和地下根系)和土壤层(0-100 cm)的碳含量, 比较了两种森林生态系统的碳密度及其分配特征, 并运用空间代替时间的方法, 阐明了乔木层、土壤层和总碳密度随林龄增加的变化特征, 估算了两种森林生态系统的固碳速率。结果表明, 榆树疏林乔木层和土壤层平均碳含量都低于小叶杨人工林, 榆树疏林生态系统总碳密度是小叶杨人工林的1/2。两种森林生态系统的总碳密度中, 乔木层碳密度和土壤层碳密度总占比98%以上; 土壤层与植被层碳密度的比值随林龄的增加而降低, 过熟林时该比值分别为1.66 (榆树疏林)和1.87 (小叶杨人工林); 榆树疏林和小叶杨人工林的乔木层、土壤层和生态系统的总碳密度随林龄的增加而增加, 其中乔木层碳密度及榆树疏林总碳密度与林龄均呈现出显著的线性正相关关系。小叶杨人工林乔木层的固碳速率约为榆树疏林的5倍, 榆树疏林生态系统和小叶杨人工林生态系统的总固碳速率分别为0.81 Mg C·hm-2·a-1和5.35 Mg C·hm-2·a-1。这一研究结果有利于估算沙地森林生态系统的碳储量, 为区域生态环境恢复和增加碳汇的政策制定提供依据。  相似文献   

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