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1.
Recent changes in agriculture (intensification or abandonment) have resulted in a critical reduction of semi-natural grasslands in Eastern Europe. Subalpine semi-natural grasslands in Transylvania, Romania, harbour a high diversity of plants and invertebrates, including endemics, and are considered refugia for numerous threatened open-land species. We investigated effects of land abandonment by examining species richness, species abundance, proportion of open-land, endemic and threatened vascular plants, gastropods, and diurnal and nocturnal Lepidoptera in extensive hay meadows (initial stage), and three seral stages of succession (early stage of abandoned hay meadow, naturally growing birch forest, and mature forest) in the mountainous region of Baisoara in Transylvania. A total of 626 species (225 vascular plants, 16 gastropods, 68 diurnal and 317 nocturnal Lepidoptera) were found in the 16 study sites (four replicates per successional stage). The four taxonomic groups differed in their response to the abandonment of hay meadows. Each stage of succession harboured the maximum species richness for one taxonomic group: extensive hay meadows for vascular plants, abandoned hay meadows for diurnal Lepidoptera, birch forests for nocturnal Lepidoptera, and mature forests for gastropods. In all four taxonomic groups the complementarity of species composition increased with successional age, whereas the number of characteristic open-land species decreased with successional age. The four successional stages did not differ in proportion of red-listed plant and diurnal Lepidoptera species. In nocturnal Lepidoptera, however, the proportion of red-listed species increased with successional age. Furthermore, successional stages did not differ in number of plant species endemic to the Carpathians and Eastern Europe. Our results indicate the high conservation value of all stages of subalpine grassland succession for the indigenous biodiversity of Transylvania. To prevent losses of characteristic species, we suggest a rotational grassland management program that maintains different successional stages.  相似文献   

2.
There is vigorous debate about the potential for reforestation to offset losses in biodiversity associated with tropical deforestation, but a scarcity of good data. We quantified developmental trajectories following active restoration (replanting) of deforested pasture land to tropical Australian rainforest, using 20 different bird community indicators within chronosequences of multiple sites. Bird species composition in restored sites (1–24 years old) was intermediate between that of reference sites in pasture and primary rainforest. Total species richness was much less sensitive to land cover change than composition indicators, because of contrasting species-specific response patterns. For example, open-country (grassland/wetland) bird species declined in richness and abundance with increasing site age, while rainforest-dependent species increased. Results from two different landscapes (uplands and lowlands) were remarkably consistent, despite differing bird assemblages. After 10 years, restored sites averaged about half the number of rainforest-dependent bird species typical of rainforest. Mean values at around 20 years overlapped with the “poorest” rainforest reference sites, but projections suggest that >150 years are required to reach mean rainforest levels, and high variability among sites means that many were not on track towards ever achieving a rainforest-like bird community. Regional rainforest endemics were half as likely to occupy older revegetated sites as non-endemic rainforest-dependent species. Between-site variability and slow colonisation by regional endemics strongly constrain the potential of rainforest restoration to offset the biodiversity impacts of tropical deforestation. The results also mean that ongoing monitoring of biodiversity is an essential part of restoration management.  相似文献   

3.
We studied the effect of sowing low-diversity seed mixtures (containing 2-3 competitive grass species) on the regeneration of vegetation on croplands previously used as alfalfa fields. In four permanent plots in 10 restored fields (four with alkali and six with loess seed mixture) the cover of flowering plants was recorded and phytomass was measured between 2006 and 2008. We asked three questions: (i) How fast will weedy, short-lived species decrease in abundance during secondary succession enhanced by sowing low-diversity seed mixtures? (ii) Can weeds be suppressed by sowing competitive native grasses, followed up by management by mowing? (iii) Can succession towards the target native grasslands be accelerated by sowing only low-diversity seed mixtures compared to set-aside old field succession? Our results showed that in just two years a vegetation dominated by perennial grasses has developed, which successfully prevented the establishment of weed species. These results suggested that sowing seeds of two or three competitive grass species is an effective tool to eliminate weed domination and to lead towards the restoration of species poor grasslands with grass domination such as alkali grasslands. However, the developed dense perennial grass cover and the accumulated litter may hamper the immigration of specialist species characteristic to reference grasslands. Therefore, the restoration of species-rich grasslands requires the facilitation of the immigration of grassland specialist species by further management (grazing, mowing and/or hay-transport).  相似文献   

4.
Conservation biology often relies on the protection of (semi)natural habitat remnants. However, the ever increasing human population is taking over natural resources and habitats. Here, contrary to most other studies, we ask how human-associated severe changes in the environment can be used to enrich local biodiversity. We tested if industrial activity (gravel excavation) leads to the creation of habitats that support grassland butterflies and how these areas add to the richness of local species when compared to typical semi-natural habitats (grasslands). We also identified key factors affecting the richness, abundance, diversity and commonness of butterfly species to provide practical recommendations. Species richness, diversity index and the occurrence of rare species were higher in gravel-pit shores than in grasslands. The richness of butterfly species and their abundance were positively affected by the richness of plant species, shrub density and age of the gravel-pit but negatively by the cover of water reservoirs in the surrounding area and the isolation of gravel-pits from grasslands. Butterfly diversity was positively influenced by the richness of plant species and proximity of human settlement but negatively by area of the shore and isolation. Our study is the first one to show the high value of gravel-pits for the conservation of butterflies. We recommend the inclusion of gravel-pits in a system of ecological networks and management of their surroundings to improve the colonization rate of rare species. We suggests that directing interest to the possible positive effects of industrial development on biodiversity may support conservation efforts.  相似文献   

5.
人工与自然恢复方式对流动沙地土壤与植被特征的影响   总被引：3，自引：0，他引：3  
[目的]分析不同固沙措施对土壤—植被系统恢复的生态效应,为该地区沙化草地选取合理的固沙措施、草场管理与利用以及沙漠化治理提供依据。[方法]以宁夏地区盐池沙地围封自然恢复草地和灌丛人工固沙林地为研究对象,以周围流动沙地为对照,对不同处理措施样地土壤性质和地表植被特征进行调查。[结果](1)两种恢复措施均能够显著增加土壤黏粉粒含量、土壤有机碳和全氮含量(p0.001),降低土壤温度、容重和含水量(p0.05),并显著提高草本植物丰富度、个体数和平均高度(p0.05)。(2)自然围封草地土壤黏粉粒含量、草本植物个体数和丰度分别是人工灌丛林地的2.1,2.8,1.4倍;而其土壤含水量下降幅度是人工灌丛固沙林地的1.7倍。人工灌丛固沙林地土壤有机碳、全氮含量以及草本植物平均高度分别是自然恢复草地的2.1,2.0,2.2倍;而其土壤容重下降幅度是自然恢复草地的2.5倍。(3)随着流动沙地固定和草本植被恢复,植物群落以一年生草本植物为特征逐渐演替到以一年生草本植物为主且伴生有多年生植物的草地生态系统。但一年生和多年生植物个体数和物种数自然恢复草地均明显高于人工灌丛固沙林地。[结论]围封自然恢复对于宁夏地区盐池沙地土壤质地与植被系统稳定性的恢复质量优于灌丛人工恢复措施,人工灌丛固沙因其能够有效改良土壤营养条件亦可作为重要辅助恢复手段。  相似文献   

6.
 通过样地法对小浪底水库库区山地生态系统不同群落间的Shannon-Wiener指数(H′)、Simpson指数(D1)、Margalef物种丰富度(D2)、种间相遇概率(P)和Pielou均匀度指数(Jsw)等多样性指数进行研究,利用统计方法分析不同群落的物种多样性指数与其所处环境的关系。结果表明:1)物种多样性指数和丰富度指数与群落类型有密切关系,同一类型的群落中,多样性指数随演替时间表现出复杂的关系;2)土壤含水量对H′、P、Jsw、D1等呈极显著的正相关性,土壤厚度与H′、D1、P呈显著正相关性;多样性指数与坡度无相关性;土壤有机质、速效氮、速效磷等养分指标与多样性指数H′、D1有显著的正相关;3)多样性指数H′与乔木、灌木群落生物量表现为正相关关系,草本群落与D1相关性不显著;4)乔木林群落的恢复时间与Jsw、H′呈正相关关系,其余多样性指数(P、D1、D2)与恢复时间关系不显著(P>0.05);恢复时间每增加10a,群落物种数平均增加约6种;5)物种多样性指数H′与灌木的盖度和高度呈极显著正相关性;有些单优群落随高度增加和盖度提高,多样性指数反而表现出降低;6)草本植物群落的高度和盖度与物种丰富度指数D2与呈显著的负相关关系,与H′相关性不显著。  相似文献   

7.
An increasing number of invasive species are changing ecosystems around the world. Road verges have commonly become the first footholds of non-native species in the new environments. Regularly mown road verges also offer habitats for meadow flora and fauna, which in Europe have suffered from the radical decline of semi-natural biotopes due to the agricultural modernization. We studied impacts of an invasive plant Lupinus polyphyllus on the plant and Lepidoptera species composition along road verges. The plant species composition was studied on 15 sites (with 1 m2 quadrats) and butterflies and diurnal moths along 15 transects (with weekly censuses) in SE Finland, each site and transect representing equally lupine invaded verge and an adjacent non-lupine verge. The species richness and diversity of flora and the cover and species richness of low growing (<20 cm) species, in particular, was lower in lupine verges compared to non-lupine verges. Also, the abundance of butterflies was lower in lupine verges. As the lupine cover approached 100%, fewer butterflies were observed in lupine transects compared to the adjacent non-lupine transects and a higher proportion of individuals were flying. Our results suggest that the changes in plant species assemblages and lower plant species richness in lupine invaded areas had “bottom-up” effects on higher trophic levels. Further studies on the control of lupine are urgently needed, but meanwhile we suggest regular mowing before the lupines have shed their seeds, together with the removal of the cuttings, to be the best management option.  相似文献   

8.
Roadsides form potential habitats for several grassland species adapted to regular mowing management. We studied the communities of butterflies and day-active moths in 51 sites along the verges of the three road types, i.e., highways, urban roads and rural roads. Despite different traffic densities and widths of the road and verge, the groups were rather similar with regard to soil properties, vegetation structure and mowing intensity. The species richness and total abundance of butterflies (53 species, 5964 individuals) and diurnal moths (46 species, 4626 individuals) were also rather similar in each road type, although a preference for wider verges was observed. Butterfly diversity increased (but not significantly) from the verges of narrow rural roads to wider highways. The highest numbers of meadow species were recorded along highways and the total abundance, especially of diurnal moths, decreased in accordance with the road size. High nectar abundance was the most important factor increasing the numbers of meadow butterflies along road verges, while meadow moths were mostly favoured by shelter provided by tall vegetation. Verges surrounded by cultivated fields were generally related to low numbers of both Lepidoptera groups, whereas adjacent forests increased the total number of all species and favoured several butterflies inhabiting forest edges. The adjacent environment inflicted compositional differences on the Lepidoptera fauna of the three road types. The results indicate that road verges should be considered an important reserve for species dependent on semi-natural grasslands in Finland. A growing interest in accommodating current roadside management for conserving biodiversity is likely to benefit Lepidoptera communities in the verge habitats.  相似文献   

9.

Purpose

There have been a number of studies on the succession of vegetation; however, the succession of soil microbes and the collaborative relationships between microbes and vegetation during land restoration remain poorly understood. The objectives of this study were to characterize soil microbial succession and to explore the collaborative mechanisms between microbes and vegetation during the restoration of abandoned land through quantitative ecology methods.

Materials and methods

The present research was carried out in the succession of a 5-year abandoned land and its conversion to Hippophae rhamnoides shrubs, Larix principis-rupprechtii plantation, and a naturally regenerated forest (mixed forest). Soil bacterial, archaeal and fungal characteristics were tested by real-time quantitative PCR assays and terminal restriction fragment length polymorphism. The richness, diversity, and evenness indices were employed to analyze plant and microbial communities’ structure. The stability of plant and microbial communities was tested using Spearman’s rank correlation. The relationships between the regeneration scenarios and environmental factors were determined through canonical correspondence analysis.

Results and discussion

The aboveground biomass was significantly different among the sites. Soil bacterial, archaeal, and fungal rRNA gene abundances did not increase significantly with increasing soil organic carbon content. There were higher correlation coefficients between plant and total microbial communities on the richness, diversity, and evenness indices and ratios of positive to negative association compared to ones between plant and individual bacteria, archaea, and fungi. Soil bulk density, clay, pH, and litter were the primary significant environmental factors affecting the structure of plant and microbial communities. The positive relationships between plant and soil bacteria, fungi, and total microbe communities, as well as the negative relationships between plant and archaea, were demonstrated.

Conclusions

The results suggested that plants promote the growth of soil bacteria and fungi during the process of community succession on a small scale; however, plants inhibit the growth of soil archaea.  相似文献   

10.
In contrast to many other western European countries, the knowledge about trends in the Swedish butterfly fauna is poor. We studied the effects of habitat and species characteristics on species turnover in 13 grassland sites in southern Sweden by comparing species richness and compositions at two separate occasions with an interval of 21 years. The mean number of species per site decreased from 30 to 24, with a large variation between sites. The number of extinctions was highest in sites where the proportion of trees and shrubs had increased most, but there was no detectable effect of area or of the composition of landscapes surrounding the sites. Areas protected as nature reserves had lost as many species as unprotected areas had, indicating both the importance of proper management of nature reserves and that nature reserves alone may not be enough to inhibit regional extinction of butterfly species. Species dependent on nutrient-poor conditions tended to decrease while species dependent on nutrient-rich conditions tended to increase, indicating a negative effect of increased soil nitrogen levels resulting from active fertilizing of pastures and/or atmospheric nitrogen deposition. A regular monitoring program could show whether our results are representative for Sweden or Northern Europe.  相似文献   

11.
Exotic plants are major constituents of species pools in modern landscapes. Managing succession for restoration of degraded ecosystems thus requires an understanding of novel trajectories unfolding in mixed, native/exotic plant assemblages. We examined trends in native and exotic species abundance over 20 years of old-field succession on set-aside farmland in the Inland Pampa, Argentina. Changes in plant cover and species richness were annually monitored on adjacent permanent plots established in different years (1978-1989). Both native and exotic species occurred in early, mid and late successional stages, exhibiting similar life-form replacement patterns, from annual forbs, through annual to perennial grasses. Exotic plant richness declined with plot age. Yet, four exotic grasses remained dominant through succession (50-70% cover), with plots initiated in later years showing increased exotic cover. While native perennial grasses occurred from the onset of succession, increasing from 5 to 12 spp/plot, they only showed transient peaks below 30% cover. Cluster analysis of 113 plot-year samples identified alternative community states for early, mid and late successional stages, which were connected by a complex network of interweaving dynamic pathways. Depending on the plot, vegetation dynamics comprised directional temporal trajectories as well as nondirectional pathways, and arrested community states dominated by exotic grasses. Our results illustrate the overwhelming role of exotic species in modern old-field succession, and their potential to hinder recovery of native communities on former agricultural land. Community states with novel, native/exotic plant mixtures could be managed to deliver specific ecosystem services (e.g. forage production, carbon sequestration). However, meeting conservation goals may require active restoration measures, including exotic plant removals and native grass seeding.  相似文献   

12.
The effects of restorative grazing on the abundance of butterfly and moth species were studied in mesic semi-natural grasslands of SW Finland differing in management history: (1) old continuously grazed, (2) restored (with ca 5 years of reinitiated grazing), and (3) abandoned former pastures.Generalized linear modelling of species abundances and indicator species analysis produced qualitatively similar results. Only three species (Polyommatus icarus, Lycaena hippothoe and Camptogramma bilineatum) were most abundant in old pastures, whereas 12 species (Polyommatus semiargus, Polyommatus amandus, Brenthis ino, Aphantopus hyperantus, Scopula immorata, Idaea serpentata, Scotopteryx chenopodiata, Epirrhoe alternata, Cybosia mesomella, Polypogon tentacularius, Hypena proboscidalis and Cryptocala chardinyi) were most abundant in abandoned pastures. None of the old-pasture species had become more abundant in restored pastures. Three species, Epirrhoe hastulata, Xanthorhoe montanata and Chiasmia clathrata, occurred equally abundantly in abandoned and in restored pastures indicating a slow progress of restoration.Species associated with old pastures differed from species associated with abandoned pastures in their recent distributional changes in Finland. The species of old pastures showed decreasing trends, whereas those of abandoned pastures showed mainly increasing trends in their distribution. In five out of 11 species, the preferred successional stage differed markedly between this study and previous studies conducted in Central Europe.We conclude that (1) ca 5 years of restorative grazing in mesic grasslands has been insufficient for the colonisation of old-pasture species in the restored sites, (2) different management intensities are needed regionally for the maintenance of grassland insect diversity and (3) application of the knowledge on successional preferences of different species in conservation management, even in climatically similar regions, should be made with caution.  相似文献   

13.
The conservation and management of biodiversity requires accurate, repeatable and cost-effective monitoring techniques. In this study, a simple and rapid methodology was employed to measure the quality of different habitats for butterfly species on 10 arable farms in lowland Britain. This habitat monitoring was seven times more rapid than the traditional species-based butterfly monitoring. Data on butterfly abundance were combined with the information gathered on habitat quality at five of the farms using stepwise regression. These models had a consistently high degree of explanatory power for the summary variables of total butterfly abundance and species richness, and the functional groupings of mobile and immobile species. There was good agreement between observed and predicted estimates of species richness and abundance when the models were validated on a further five independent sites. Models to predict the abundance of 11 common butterfly species were also produced. These varied considerably in their predictive power and validity between species. The results clearly demonstrated the beneficial effects of targeted habitat creation for butterflies which is promoted under the Agri-environment Schemes, especially the recently introduced pollen and nectar seed mixtures (WM2) available under the Countryside Stewardship Scheme. The models confirmed the importance of shelter, floristically diverse field margins and the availability of nectar resources from legume species in explaining the abundance of immobile butterfly species in arable landscapes. These sources of nectar and the presence of larval host plants in the crucifer family were important factors in explaining the abundance of mobile species. The results are discussed in terms of the potential of this approach for: (i) assessing habitat quality for butterflies in intensively managed landscapes; (ii) enhancing the value of butterfly monitoring schemes in explaining changes in butterfly abundance at the site and national scale; and (iii) informing habitat management and restoration guidelines for butterfly conservation on arable farmland.  相似文献   

14.
Alien plant invaders significantly threaten native community diversity, although it is poorly understood whether invasion initiates a linear or non-linear loss of resident species. Where low abundances of an invader have little impact on native species diversity, then a threshold level may exist, above which native communities rapidly decline. Our aim was to assess the broadscale effects of an alien thicket-forming shrub, lantana (Lantana camara L.), on wet sclerophyll forest in southeastern Australia. Vascular plant species richness, abundance and composition were measured and compared along a gradient of lantana invasion. There was a strong negative non-linear relationship between native species richness and lantana cover, indicative of an impact threshold. Native species richness remained stable below 75% lantana cover, but declined rapidly above this threshold level, leading to compositional change. Thus, sparse lantana infestations had evidently little effect on the resident community, with impacts elicited at an advanced stage of invasion. The impact of lantana was pervasive, with all major structural groups (i.e. ferns, herbs, shrubs, trees and vines) exhibiting significant species losses; however, the rate of species loss was relatively greater for tree and shrub species, signalling a shift in vegetation structure from tall open forest to low, dense lantana-dominated shrubland. Potentially, broadscale conservation of species diversity could be achieved by maintaining lantana infestations below the 75% cover impact threshold at sites containing regionally common species that are also widely represented in non-invaded vegetation. This would enable targeted invader eradication at sites of high conservation value (i.e. those containing regionally rare species or endangered ecological communities).  相似文献   

15.
天然草地退化引起草地植被和表层土壤遭到严重破坏,将使草地植被天然恢复过程受到强烈抑制。为此,试验采用长期(40年)封禁恢复技术,探究了封禁后黄土区退化草地植被变化特征,揭示了退化天然草地封禁恢复后的生态环境效应。结果表明：随着封禁恢复时间的变化,退化草地恢复演替已经历了5个时间段;草地生物量的变化过程已呈现出由先增加到后降低的趋势,尤其是在封禁恢复的第20年生物量达到最高值为520.5 g/m2;直到封禁恢复的第25年出现以本氏针茅为建群种的草原群落,第25年之后优势种大针茅种群密度急剧增加,在封禁的第30～34年以大针茅为群落的优势种生长繁殖较快,从群落恢复进程看大针茅有替代本氏针茅的趋势,但大针茅为有性繁殖,受草地凋落物的影响在群落中持续时间较短;从自然修复的35年后,通过种间竞争—扩散—定居—稳定生长的几个作用机制,又形成了以本氏针茅为建群种的“亚顶级”群落。此外,封禁后的草地物种丰富度和多样性逐渐提高。综上,封禁有利于黄土区草地生态系统恢复,且随着封禁时间的推演,草地生态系统逐渐趋于良性循环。  相似文献   

16.
The increasing spread of invasive alien plants has changed biodiversity throughout the world. To date research in this area has focused on how invasive plant species affect pollinator behaviour, but there is a lack of data on the impact that alien plant species have on wild pollinator populations. Since their introduction in the 19th century, and rapid spread after the 1950s, alien goldenrods (Solidago canadensis, Solidago gigantea) have been among the most successful invasive plant species in Europe. We studied the effects of goldenrods on wild pollinator communities in SE Poland. The abundance, species richness and diversity of wild bees, hoverflies and butterflies were compared between wet meadows invaded by goldenrod (10 transects) and non-invaded controls (10 transects). Furthermore, we compared the plant diversity and average cover between the two groups of sites. Invasion of goldenrods had a very strong negative effect on wild pollinator diversity as well as abundance. Plant diversity and average cover were also negatively affected by goldenrod invasion. Wild pollinators were grouped according to their nesting and food specialization, but none were resistant to the invasion, indicating that introduced goldenrod may affect the entire wild pollinator community. Our study emphasises the urgent need to develop specific protection plans for wild pollinators in habitats threatened by foreign plants and we call for the introduction of programs to stop the invasion of goldenrod not only in Poland, but also on a continental scale.  相似文献   

17.
基于华北土石山区潮关西沟流域天然森林植被调查的基础上．对森林植被群落演替中群落树种组成、胸径结构和生物多样性变化进行了研究。结果表明，随着演替的进行．群落的乔灌木树种数先升高后降低，趋于稳定。而乔木密度呈增加趋势，而灌木密度和乔木树种的最大株数比例的胸径范围呈不断降低趋势。群落的乔木、灌木和乔灌木的物种多样性、丰富度随着演替的进行先升高后降低。除了栎树林乔木和平榛灌丛的乔灌木的均匀度较低外，乔木、灌木和乔灌木其他群落的均匀度变化不明显。  相似文献   

18.
《CATENA》2005,59(2):173-186
The Bashang area, located in the semiarid agropastoral zone, represents a typical degraded ecosystem under intensified human activities. This region has undergone profound land use changes during the past century. Natural grasslands had been progressively cultivated, and subsequently, part of cultivated lands had been abandoned by farmers due to severe desertification. In this study, we collected soil samples (0–20 cm depth) from four farmlands on both flat and gentle slope lands where cultivation had occurred for 0, 8, 30, and 50 years to assess the effects of grassland cultivation on soil degradation. In addition, soil samples were taken and plant species were investigated from eight sites in age sequence of 0- to 50- year-old abandoned field to assess natural restoration process following field abandonment. The results showed that cultivation of grassland result in a significant soil degradation which is manifested by the coarsening in soil texture and the losses in organic C and nutrients. After 50 years of cultivation, soil organic C, total N, and total P concentrations had declined 73–79%, 60–70%, and 67–68% in the 0–20 cm plough layer, respectively. Over half of these losses occurred during the first 8 years of cultivation, and subsequent was slow. After fields were abandoned, vegetation got self-restoration, and plant species composition moved toward that of the natural grassland community with time. Soil organic C, total N, and total P levels gradually improved with increasing years of land abandonment, with a faster restoration rate in the early vegetation recovery stage and a slower rate in the late succession stage. The results suggested that soil degradation may occurred drastically by inappropriate land use and management with a short time, while soil restoration for a degraded ecosystem may take long period of time, especially in this fragile ecosystem. From the perspective of soil resource management and desertification control, conservational tillage and management for farmlands and proper grazing management for recovered grassland should be taken into account in this area.  相似文献   

19.
[目的]对甘肃省金川矿山废弃地修复区内主要的林分进行植物含碳率测定,估算修复区内的植被碳储量,为矿区生态修复系统纳入中国温室气体自愿减排提供科学依据。[方法]利用干烧法对修复区主要物种进行有机含碳率测定,估算修复区内主要物种的平均含碳率、植被储碳密度和碳储量,并对其特征进行分析。[结果]在修复区,乔木的含碳率在0.462 9~0.403 8,灌木的含碳率范围为0.413 9~0.453 6,8种草本植物的平均含碳率为0.144 5,整体上表现为:乔木灌木草本植物。金川矿山废弃地生态修复区植被平均储碳密度为6.209 2t/hm~2,总碳储量为635.10t,在总碳储量分配中,乔木较高,占86.71%,灌木次之(占12.65%),草本植物在总碳储量中所占比例不大。[结论]对矿山废弃地进行生态恢复,能够增加矿区植被储碳量,在纳入中国温室气体自愿减排上有很大的潜力空间。  相似文献   

20.
We studied the impact of the invasive plant species Solidago canadensis on the species richness of vascular plants and the abundance, species richness and diversity of butterflies, hoverflies and carabid beetles in herbaceous semi-natural habitats near Ljubljana, Slovenia. The species groups were sampled in sites dominated by S. canadensis and paired nearby sites covered by semi-natural vegetation. Plant species richness and species richness, abundance and diversity of butterfly species were lower in plots dominated by S. canadensis. Hoverfly abundance, diversity and species richness were negatively affected only in July just before the onset of flowering of S. canadensis, but tended to be positively affected in August during the height of flowering of S. canadensis. Only the abundance of carabid beetles was reduced in plots dominated by S. canadensis. The responses of the insect groups seem largely driven by the effects of Solidago on the availability of essential resources like food or larval host plants. Our results suggest that insect species that are closely related to plant species composition are more vulnerable to the effects of invasive plant species than those that are loosely or only indirectly related to plant species composition.  相似文献   

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