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1.
通过对铜陵市狮子山铜尾矿废弃地植被的实地调查,探讨了该废弃地的植被状况及其植被恢复过程中的植物群落形成与演替的一般规律与特征.结果表明:目前废弃地入侵、定居植物共49种,隶属于15科38属,主要包括菊科(12种)、禾本科(11种)、豆科(8种)等.极端贫瘠和过高的重金属含量(特别是Cu、Cd,平均超出对照土样的20~30倍)是限制植物在废弃地定居的主要因素.全部植物中,一、二年生草本植物26种,多年生草本植物20种.风播种子和果实是废弃地植物繁殖体的主要来源.尾矿废弃地植物群落形成具有先锋植物的入侵、定居、群聚和竞争等过程,共形成了14种相对稳定的小群落,包括单优势种群落、次优势种群落和共优势种群落三种类型.伴随着尾矿废弃地植物群落的形成与演替,群落中物种丰富度增大,多样性指数呈增加趋势,而群落内植物种综合优势比间的差值趋于减小.  相似文献   

2.
选取黄土高原区黑岱沟露天煤矿不同复垦阶段(1995~2010年)样地4块,以原地貌样地为对照,以时空替代的方法,对煤矿复垦地的植物群落的功能群结构及生物多样性进行研究.结果表明:(1)随着复垦时间的延长,植物群落功能群组成以多年生禾草和多年生杂类草为主,其累积优势度均呈现增加的趋势,而一、二年生草本的累积优势度减小;复垦初期,群落功能群单一、组成种类贫乏,多为一、二年生植物;复垦后期,羊草及冰草逐步出现,复垦地最终形成以克氏针茅、本氏针茅、赖草及糙隐子草为主的植物群落.(2)复垦过程中,中生植物及中旱生植物所占比例逐步增加,而旱生植物比例逐步减少;多年生禾草及多年生杂类草生物量随着复垦时间的增加而递增,而一、二年生草本植物生物量递减;群落总生物量呈先急剧增加、又急剧减少、后缓慢增加的规律.(3)群落的Shan-non-Wiener多样性指数(H)、Patrick丰富度指数(Pa)及Pielou均匀度指数(JP)随着复垦时间延长而增加.  相似文献   

3.
We investigated species richness of ground dwelling beetle assemblages in two non-reclaimed lignite mines and a dump in Central Germany by means of pitfall trapping. During a period of five months, a total of 203 beetle species within 27 families represented by 4099 individuals were trapped. This included 75 species of ground beetles represented in a sample of 957 individuals from which 10 species are regionally endangered. The number of individuals, species richness, as well as the proportions of endangered species did not differ between successional stages whereas species composition of sites could be related well to a set of environmental variables. High values of beta-diversity between sites indicated that the total number of species recorded is caused by habitat diversity. From the viewpoint of nature conservation, we conclude that postmining areas can play a key role in conservation of beetle diversity in agricultural areas since they harbour threatened species whose original habitats are now rare due to human impact. An important task for future management of postmining areas is to maintain successional processes and to prevent loss of habitat diversity through afforestation. Areas with extreme soil conditions should also be preserved for long-term availability of bare soil and pioneer vegetation and associated fauna.  相似文献   

4.
Restoration projects are often developed with little consideration for understanding their effects on wildlife. We contend, however, that monitoring treatment effects on wildlife should be an integral component of the design and execution of any management activity, including restoration. Thus, we provide a conceptual framework for the design and implementation of monitoring studies to understand the effects of restoration on wildlife. Our underlying premise is that effective monitoring hinges on an appropriate study design for unbiased and precise estimates of the response variables. We advocate using measures of population dynamics for response variables given that they provide the most direct measures of wildlife status and trends. The species to be monitored should be those constituting an assemblage of umbrella species that represent the range of spatial and functional requirements of wildlife in a restored ecological system. Selection of umbrella species should be based on strong empirical evidence that justifies their usage. We also advocate that monitoring be designed as true experiments or quasi‐experiments rather than as observational studies to allow for stronger inferences regarding the effects of restoration on wildlife. Our primary message is that if monitoring is to be done, it must be scientifically based.  相似文献   

5.
We compared four types of 30‐year‐old forest stands growing on spoil of opencast oil shale mines in Estonia. The stand types were: (1) natural stands formed by spontaneous succession, and plantations of (2) Pinus sylvestris (Scots pine), (3) Betula pendula (silver birch), and (4) Alnus glutinosa (European black alder). In all stands we measured properties of the tree layer (species richness, stand density, and volume of growing stock), understory (density and species richness of shrubs and tree saplings), and ground vegetation (aboveground biomass, species richness, and species diversity). The tree layer was most diverse though sparse in the natural stands. Understory species richness per 100‐m2 plot was highest in the natural stand, but total stand richness was equal in the natural and alder stands, which were higher than the birch and pine stands. The understory sapling density was lower than 50 saplings/100 m2 in the plantations, while it varied between 50 and 180 saplings/100 m2 in the natural stands. Growing stock volume was the least in natural stands and greatest in birch stands. The aboveground biomass of ground vegetation was highest in alder stands and lowest in the pine stands. We can conclude that spontaneous succession promotes establishment of diverse vegetation. In plantations the establishment of diverse ground vegetation depends on planted tree species.  相似文献   

6.
The methods employed in a restoration can impact the resulting plant community. This study investigated the effect of restoration method on several indices of plant community structure by comparing two restoration methods conducted over an 8‐year period to a naturally colonized postagricultural field and a remnant grassland. The restoration methods included (1) distributing seed over fallow fields and (2) planting established seedlings in combination with seeding a fallow field. We found greater plant community resemblance (i.e., floristic quality, native species richness, and native diversity) to remnant grasslands with the introduction of seedlings during the first 4 years of restoration. There was also a negative correlation between the native plant diversity and the density of exotic plants in the restoration. This relationship suggests that introducing native plants in postagricultural fields may represent an effective management strategy to reduce exotic plant density.  相似文献   

7.
After a community or ecosystem is lost, it may leave behind an ecological memory. The site history, soil properties, spores, seeds, stem fragments, mycorrhizae, species, populations, and other remnants may influence the composition of the replacement community or ecosystem to varying degrees. The remnants may also hold the site to a trajectory that has implications for ecological restoration. This is true in urban situations in particular where repeated disturbance has masked the history of the site. The ecological memory remaining may be insufficient for a site to heal itself; restoration activities are required to direct the future of the site. Conversely, in light of climate change and other rapidly changing environments, the existing ecological memory may be poorly suited to the new conditions and restoration projects need to create new and perhaps novel ecosystems. The loss of ecological memory facilitates the establishment of foreign invasive species. These invasives may eventually create a new stability domain with its own ecological memory and degree of resilience. To be successful, invasive species control must address both internal within patch memory of invasives and external between patch memory. Further research is necessary to document and conserve ecological memory for ecological restoration in response to future ecosystem changes.  相似文献   

8.
Spoil heaps of surplus rock from hydropower tunnel construction negatively impact alpine landscapes unless restored. Such spoil heaps have been created for more than 100 years, but we still lack knowledge about the relative importance of compensatory mitigation (seeding and fertilization), spoil‐heap construction method, local environmental factors, and regional climatic factors for restoration success. We studied the species composition of 19 alpine spoil heaps in Western Norway and their undisturbed surroundings using ordination and statistical modeling. Substrate grain size was the principal factor explaining differences in species composition between spoil heaps and their surroundings. Soil characteristics, that is, organic matter content and pH, and reutilization of topsoil were also important. Seeding and fertilization had negligible effects on restoration success. Slow recovery was observed for total vegetation cover and species richness of vascular plants and lichens while bryophyte cover recovered rapidly. Lower bryophyte cover and bryophyte and vascular plant species richness on older than on younger spoil heaps indicated recent changes in spoil‐heap construction practices that favor plant colonization. Our results indicate that spoil‐heap design is more important for restoration success than compensatory mitigation. We therefore suggest spoil heaps designed with a fine‐grained top substrate preferably from stockpiled local topsoil, with uneven surface topography that mimics natural topographic variation, and recommend discontinuation of seeding and fertilization.  相似文献   

9.
Restoration ecology requires theoretical consideration of a habitat’s former structure and function before the practice of ecological restoration is applied. However, experience has shown that this does not always occur and aspects such as soil ecology have often been an afterthought. Here, case study material relates the use of earthworms at selected sites in the United Kingdom. Due to their soil‐forming capabilities, these organisms may be essential to reconstruction of soils when drastic activities have despoiled an area. While describing in brief the type of work undertaken, these case studies seek to illustrate some of the misunderstandings/problems/deliberately negative acts that have too often accompanied use of earthworms in soil restoration. From such experiences, implications for practice are suggested that should lead to a greater understanding and appropriate utilization of earthworms in future projects.  相似文献   

10.
Restoration of coastal dune slacks in the Netherlands   总被引:6,自引:1,他引:5  
Grootjans  A.P.  Geelen  H.W.T.  Jansen  A.J.M.  Lammerts  E.J. 《Hydrobiologia》2002,478(1-3):181-203
In order to stop the continuous decline of typical dune slack communities along the Dutch coast, restoration projects have been carried out since 1952. Restoration measures consisted of re-introducing traditional management techniques in dune slacks, such as mowing, grazing and sod removal, or constructing artificial dune slacks to compensate for lost biodiversity elsewhere. An analysis of successful and unsuccessful projects showed that constructing new dune slacks was not very successful for maintaining new populations of endangered dune slack species, since such projects were often carried out in areas where seed banks were depleted, while hydrological conditions and seed dispersal mechanisms were sub-optimal. The construction of sand dikes to prevent sea intrusion in large beach plains was, unintentionally, a temporary success for the establishment of many Red List species, although such measures often disrupted natural dune slack formation. Successful sites were all characterised by a regular discharge of calcareous groundwater provided by local or regional hydrological systems, where not very long ago populations of typical dune slack plants were present. Under such conditions, sod removal was a successful measure to create pioneer stages which were relatively stable, due to a very slow accumulation of organic matter in the topsoil. It is argued that new and more flexible coastal defence strategies can provide new opportunities for natural and relatively stable pioneer stages of dune slack formation, suitable for the long term preservation of endangered dune slack species.  相似文献   

11.
We used LANDIS, a model of forest disturbance and succession, to simulate successional dynamics of forests in the southern Appalachian Mountains. The simulated environments are based on the Great Smoky Mountains landscapes studied by Whittaker. We focused on the consequences of two contrasting disturbance regimes—fire exclusion versus frequent burning—for the Yellow pine (Pinus L., subgenus Diploxylon Koehne) and oak (Quercus L.) forests that occupy dry mountain slopes and ridgetops. These ecosystems are a conservation priority, and declines in their abundance have stimulated considerable interest in the use of fire for ecosystem restoration. Under fire exclusion, the abundance of Yellow pines is projected to decrease, even on the driest sites (ridgetops, south‐ and west‐facing slopes). Hardwoods and White pine (P. strobus L.) replace the Yellow pines. In contrast, frequent burning promotes high levels of Table Mountain pine (P. pungens Lamb.) and Pitch pine (P. rigida Mill.) on the driest sites and reduces the abundance of less fire‐tolerant species. Our simulations also imply that fire maintains open woodland conditions, rather than closed‐canopy forest. For oaks, fire exclusion is beneficial on the driest sites because it permits oaks to replace the pines. On moister sites (north‐ and east‐facing slopes), however, fire exclusion leads to a diverse mix of oaks and other species, whereas frequent burning favors Chestnut oak (Q. montana Willd.) and White oak (Q. alba L.) dominance. Our results suggest that reintroducing fire may help restore decadent pine and oak stands in the southern Appalachian Mountains.  相似文献   

12.
From the moment of its inception, human choice about how to treat the environment is a key part of ecological restoration. Because many, if not most, restoration projects require continual management once established, human choice remains a vital component of restoration projects for their entire life. But ecological restorationists often downplay the role of choice in restoration, partly because we see the choice to restore as obvious and inherently good and partly because we feel the restoration of more natural conditions for a habitat will lessen the impact of human choice over time. Some critics feel the role of human choice in restoration degrades the value of restoration. However, another response to human choice in restoration is to embrace choice, even with the problems it brings, and use choice as a way to more fully engage humans with the environment. If such choices are approached carefully, with recognition of the potential for poor choices, then restorationists can arrive at restorations that are better for both the environment and us.  相似文献   

13.
丛枝菌根在退化土壤恢复中的生态学作用   总被引:10,自引:0,他引:10  
方治国  陈欣 《生态学杂志》2002,21(2):61-63,F004
土壤退化 (包括土壤侵蚀、贫瘠化、盐碱化、沙化、酸化 )不仅为全球所关注 ,而且是关系到我国农业可持续发展的重大问题。全球 1.3× 10 8km2 的总土地面积中 ,因人为原因引起的退化面积为 2 0×10 7km2 ,这些退化土壤中 ,耕地近 5× 10 8ha ,约占总耕地面积的 1/ 3。我国南方丘陵区土壤退化问题也突出 (水土流失面积 8 0× 10 7ha ,养分贫瘠化 1 9×10 7ha ,污染土壤 3 2× 10 6ha ,酸化土壤 3 2×10 6ha) ,因而探讨恢复和重建退化土壤的途径已成为该地区农业持续发展的重要内容[5] 。菌根 (mycorrhiza)是土…  相似文献   

14.
It is essential to understand how ecological restoration (ER) improves human well‐being in order to justify more investments and upscaling in this emergent field of action. As part of a 22‐year‐old, 80 ha ER project being carried out around a water reservoir that supplies drinking water to the city of Iracemápolis (population 19,700), in the mega‐diversity Atlantic Forest biome of Brazil, we assessed local community perceptions of the tangible and intangible benefits expected to arise from this project. A detailed questionnaire was completed for 292 members of the local community to gauge perceptions of benefits arising from various cultural and provisioning ecosystem services (ESs; especially safe and clean drinking water) provided by the 80 ha forest restoration project. A striking 94% of those interviewed wanted more ER projects in their community. Participants reported an appreciation for cultural ESs such as esthetic landscape improvement, tourism, recreation, as well as various religious, spiritual, and educational services. In addition, 87% of interviewees believed that the restoration project improved the quality of their drinking water, and 63% said they would agree to an increase in water tariffs if the proceeds were to be invested in more forest restoration. Judging from this study, investigation and subsequent communication of popular perceptions of the various benefits of ER projects could promote consensus‐building and support for projects among stakeholders, and inform governmental and societal investments in restoration .  相似文献   

15.
We address the question: under which circumstances can we rely upon spontaneous succession and when are technical measures more effective in restoration programs? To answer this question, the position of a disturbed site along the productivity–stress gradient was considered. The probability of attaining a target stage by spontaneous succession decreases toward both ends of the productivity–stress gradient, whereas the acceptance of technical measures generally increases. In correspondence with that, the monetary cost of restoration increases toward the ends of the gradient. Therefore, spontaneous succession is advocated especially if environmental site conditions are not very extreme.  相似文献   

16.
The Use of Case Studies in Establishing Feasibility for Wetland Restoration   总被引:4,自引:0,他引:4  
Establishing restoration feasibility is a multifaceted process that requires consideration of the ecological, social, and economic conditions of a given site. Examining completed restoration projects that report successes and failures may enhance this complex decision‐making process. We describe five completed wetland restoration projects and identify commonalities among them to inform the process of establishing feasibility for proposed restoration projects. Most of the case studies identified the need to gather preexisting and historical information, develop scenarios through hydrologic modeling, study the restoration materials, use best professional judgement for unanswered questions, establish multigroup collaboration, gain public support from stakeholders, and monitor postrestoration. We applied these lessons to a study that evaluated the feasibility of restoring Dyke Marsh Preserve, a tidal freshwater marsh in Virginia that the National Park Service is mandated to preserve. We found that the use of case studies substantially increased confidence in the decision‐making process by focusing discussions on the most important ecological, social, and economic aspects of a potential restoration.  相似文献   

17.
The Society for Ecological Restoration (SER) published the second edition of its International Principles and Standards for the Practice of Ecological Restoration in 2019. We conducted a pan-Canadian study using semi-structured interviews with restoration professionals to explore the extent to which restoration practitioners are aware of the document and use it. Overall, we found that direct uptake of the document by practitioners was lower than expected, with approximately 37.7% of all participants that were both aware of and consulting the publication for guidance in their practice of ecological restoration. This is due in part to low awareness of the document itself, with only a small majority (56.5%) of interviewees being aware of it. Other reasons listed by practitioners such as the structure of the publication, its added value, and its suitability for on-the-ground work revealed why some individuals aware of the existence of the document still failed to consult it. Here, we present a more nuanced assessment of these observations and share our findings with the ecological restoration community to address this disconnection. With intensifying pressures to achieve restoration success internationally, SER's guidance is critical. We analyze why it seems guidance from SER is not being taken up as fully as it might, and ways in which future versions may be improved.  相似文献   

18.
Abstract We compared the floristic composition and structure of restoration areas of eucalypt woodland with untreated pasture (control) and remnant vegetation (reference) in western Sydney. The restored areas comprised over 1,000 ha of abandoned pasture, which had been treated to reduce weeds and planted with seedlings of 26 native plant species raised from seed obtained locally from remnant vegetation. Plantings were carried out 0–9 years ago. Floristic composition was measured in quadrats using frequency scores and cover abundance. As far as possible treatments and restoration ages were replicated across sites. Ordination and analyses of similarity failed to distinguish the composition of restored vegetation from that of untreated pasture, which were both significantly different from that of remnant vegetation. There was a weak compositional trend with age of restored vegetation, but this was not in the direction of increasing resemblance to remnant vegetation. There was some evidence for convergence in structural features of restored with remnant vegetation, but this was at least partly attributed to plant growth. Subject to constraints imposed by the sampling design, environmental factors, and spatial variation were discounted as explanations for the results. The results therefore suggest either failure of restoration treatments or a restoration trajectory that is too slow to detect within 10 years of establishment. Our conclusions agree with those of similar studies in other ecosystems and support: (1) the need to monitor restoration projects against ecological criteria with rigorous sampling designs and analytical methods, (2) further development of restoration methods, and (3) regulatory approaches that seek to prevent damage to ecosystems rather than those predicated on replacing losses with reconstructed ecosystems.  相似文献   

19.
Ant (Hymenoptera: Formicidae) assemblages were sampled with pitfall traps in three different habitats associated with a rehabilitated mine district and in undisturbed forests in Tuscany, Italy. The four habitats were (1) open fields (3–4 years old); (2) a middle‐age mixed plantation (10 years); (3) an old‐age mixed plantation (20 years); and (4) an oak woodland (40 years) not directly affected by mining activities. The aim of the study was to analyze ant recolonization patterns in order to provide insights on the use of Mediterranean ant fauna as indicators of restoration processes. Species richness and diversity were not significantly different among the four habitats. However, multivariate analyses showed that the assemblages in the different habitats were clearly differentiated, with similarity relationships reflecting a successional gradient among rehabilitated sites. The observed patterns of functional group changes along the gradient broadly accord with those of previous studies in other biogeographic regions. These were (1) a decrease of dominant Dolichoderinae and opportunists; (2) an increase in the proportion of cold‐climate specialists; and (3) the appearance of the Cryptic species in the oldest plantations, with a maximum of abundance in the woodland. In conclusion, the results of our study supported the use of Mediterranean ants as a suitable tool for biomonitoring of restoration processes, and in particular, the functional group approach proved a valuable framework to better interpret local trends in terms of global ecological patterns. Further research is, however, needed in order to obtain a reliable classification of Mediterranean ant functional groups.  相似文献   

20.
大型露天煤矿开采引发的土地退化问题复杂,其废弃地的生态重建更是涉及采矿学、地貌学、农学、林学、生态学、环境学、经济学和社会科学等理论。因而,很难用传统的思维方法、数量化和数学模型的应用及研究工具来解决。建立废弃地生态重建智能决策支持系统(Inteli...  相似文献   

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