Assessing the impact of revegetation and weed control on urban sensitive bird species

Nature in cities is concentrated in urban green spaces, which are key areas for urban biodiversity and also important areas to connect people with nature. To conserve urban biodiversity within these natural refugia, habitat restoration such as weed control and revegetation is often implemented. These actions are expected to benefit biodiversity, although species known to be affected by urbanization may not be interacting with restoration in the ways we anticipate. In this study, we use a case study to explore how urban restoration activities impact different bird species. Birds were grouped into urban sensitivity categories and species abundance, and richness was then calculated using a hierarchical species community model for individual species responses, with “urban class” used as the hierarchical parameter. We highlight variable responses of birds to revegetation and weed control based on their level of urban sensitivity. Revegetation of open grassy areas delivers significant bird conservation outcomes, but the effects of weed control are neutral or in some cases negative. Specifically, the species most reliant on remnant vegetation in cities seem to remain stable or decline in abundance in areas with weed control, which we suspect is the result of a simplification of the understorey. The literature reports mixed benefits of weed control between taxa and between locations. We recommend, in our case study site, that weed control be implemented in concert with replanting of native vegetation to provide the understory structure preferred by urban sensitive birds. Understanding the impacts of revegetation and weed control on different bird species is important information for practitioners to make restoration decisions about the allocation of funds for conservation action. This new knowledge can be used both for threatened species and invasive species management.     

Foraging height and landscape context predict the relative abundance of bird species in urban vegetation patches

In Australian urban environments, revegetation and vegetation restoration are increasingly utilized conservation actions. Simple methods that help assess the utility of urban vegetation for bird species will help direct this effort for bird conservation purposes. We therefore examine whether ecological principles can be used to predict, a priori, the relative abundance of different bird species in urban vegetation. Our model proposes that a bird species will be in greater abundance where vegetation structure better reflects its foraging height requirements, and this relationship will be moderated by the landscape context of the patch. To quantify and test this model, we created an index to rank existing and revegetated urban vegetation sites in order of greatest expected abundance for each of 30 bird species. We tested this model, alongside two simpler models which consider landscape context and foraging height preferences alone, using bird abundance data from 20 woodland remnants and 20 revegetated sites in Brisbane, Australia. From these bird abundance data, we calculated the relative abundance of each species between the top‐ranking sites and lowest‐ranking sites. The model which incorporated both foraging height requirements and landscape context made predictions that were positively correlated with the data for 77% of species in remnant vegetation and 67% in revegetation. The results varied across species groups; for example, we achieved lower predictive success for canopy foraging species in the less mature revegetation sites. Overall, this model provided a reasonable level of predictive accuracy despite the diversity of factors which can influence species occurrence in urban landscapes. The model is generic and, subject to further testing, can be used to examine the effect of manipulating vegetation structure and landscape context on the abundance of different bird species in urban vegetation. This could provide a cost‐effective tool for directing urban restoration and revegetation efforts.     

植被重建对露天煤矿排土场土壤酶活性的影响

植被重建是露天煤矿排土场生态恢复的关键措施,深入了解植被建设对土壤酶活性的影响,对于合理选择适宜于矿区生态恢复的人工植被和加速矿区土壤生态恢复具有重要意义。通过野外调查采样和室内分析,研究了黑岱沟露天煤矿排土场植被重建和恢复对浅层(0—20 cm)土壤酶活性(包括3种氧化还原酶:过氧化氢酶、多酚氧化酶、脱氢酶,4种水解酶:蔗糖酶、脲酶、磷酸酶、纤维素酶)的影响。结果表明:相比未进行植被建设的新排土场裸地,植被重建显著改善了土壤酶活性和理化性质,建植18a后土壤酶活性可恢复到天然植被区的65%—76%,水解酶恢复速率(平均为86.9%)快于氧化还原酶(平均为42.7%),其中土壤磷酸酶恢复速率最快(平均为天然植被区的154.7%),其次为蔗糖酶(74.3%)、纤维素酶(59.9%)、脲酶(58.5%)、过氧化氢酶(52.1%)和脱氢酶(38.1%),多酚氧化酶恢复最慢(为37.8%)。植被恢复进程中,建植10a期土壤酶活性年均恢复速率最快(平均为6.0%/a),15a变缓(4.8%/a),18a迅速降低(3.2%/a)。同时植被配置类型对土壤酶活性影响显著,土壤酶活性与土壤主要理化因子具有较高的相关性。上述结果反映了植被重建能显著改善矿区排土场的土壤酶活性,植被恢复进程中水解酶恢复速率快于氧化还原酶,恢复初期快于后期,但土壤酶活性的恢复需要一个漫长的过程。     

Why monitoring often fails to inform adaptive management: a case study

Monitoring that facilitates adaptive management requires us to link observed changes in resource condition with management actions. Here, we present a case study to discuss how monitoring should be undertaken so it can facilitate adaptive management. Drawing on monitoring data collected by landholders as part of an incentive programme for native vegetation conservation on private land, we examined whether it was possible to determine to what extent changes in native vegetation condition were affected by funded management actions. Using a simple statistical technique (linear regression), we were unable to find strong links between the intended natural resource management (NRM) outcomes and funded management actions because (i) we could only use data from 22% of the 55 monitored sites as most data sheets were incomplete; (ii) sampling was undertaken in different seasons making it difficult to distinguish change due to management from change due to natural variability; and (iii) management actions were recorded in a generic way only, and not monitored through time, thus making it difficult to link observed changes in vegetation condition to on‐ground management. We suggest that monitoring programmes will only inform adaptive management where NRM bodies can prosecute (i) sampling designs that enable change as a result of management to be distinguished from change due to natural variability, and (ii) protocols that provide consistent data capture between sites and through time.     

Relationships between plant diversity,vegetation cover,and site conditions: implications for grassland conservation in the Greater Caucasus

Overgrazing, land use abandonment and increasing recreational activities have altered the vegetation of high-montane and subalpine grassland of the Caucasus. The failure of previous restoration efforts with unsuitable and exotic plant species indicates the need for information on the present vegetation and in which way it might change. Within the Greater Caucasus, we have described and quantified the mountain grassland which develops under characteristic overgrazed and eroded site conditions. Further, we have proposed potential native plant species for revegetation to restore and conserve valuable mountain grassland habitats. We used non-metric dimensional scaling ordination and cluster comparison of functional plant groups to describe a gradient of grassland vegetation cover. For our study region, we identified four major vegetation types with increasing occurrence of ruderal pasture weeds and tall herb vegetation on abandoned hay meadows within the subalpine zone. Within high-montane grassland a decline of plant diversity can be observed on sites of reduced vegetation cover. Due to a low potential of the grassland ecosystem to balance further vegetation cover damage, the long-term loss of diverse habitats can be expected. We conclude with management recommendations to prevent erosion and habitat loss of precious mountain grasslands.     

Outcomes from engaging urban community groups in publicly funded vegetation restoration

Community‐based ecological restoration (CBR) has been encouraged by government funding schemes worldwide to help reverse ecosystem degradation, although many observers have questioned their longer‐term outcomes. We investigated the ecological and social outcomes of community‐based revegetation projects in an urban context, using the case study of all CBR groups located within 25 km of the Brisbane CBD which had been funded during 1997–2008 by the Australian Government's Natural Heritage Trust program to undertake revegetation works and which were also available for interview (N = 9 groups). First we reviewed the funding allocation within the region. Second, we conducted rapid on‐ground assessments of vegetation outcomes at 10 project sites several years after works were completed, which showed that the detectable area of established revegetation averaged 75% of the area planned, and the achieved revegetation areas varied greatly, both in total and in relation to cost. Third, we undertook thematic analysis of semi‐structured interviews with key group members, revealing that groups viewed the NHT scheme's short‐term funding and lack of administrative flexibility as being largely incompatible with both quantitative monitoring (which groups did not prioritise) and longer‐term maintenance of sites for successful vegetation establishment. Interactions with local governments were considered important to success, but internally‐conflicting policies of local and state governments, together with unforeseen site disturbances, acted to limit the achievement of projects' revegetation goals. Volunteer involvement and motivation were an important part of groups' activities. Overall, these CBR projects achieved modest short term environmental benefits together with a range of social benefits. There is a need for new CBR models aimed at maximising both environmental and social outcomes.     

High‐resolution riparian vegetation mapping to prioritize conservation and restoration in an impaired desert river

In highly impaired watersheds, it is critical to identify both areas with desirable habitat as conservation zones and impaired areas with the highest likelihood of improvement as restoration zones. We present how detailed riparian vegetation mapping can be used to prioritize conservation and restoration sites within a riparian and instream habitat restoration program targeting 3 native fish species on the San Rafael River, a desert river in southeastern Utah, United States. We classified vegetation using a combination of object‐based image analysis (OBIA) on high‐resolution (0.5 m), multispectral, satellite imagery with oblique aerial photography and field‐based data collection. The OBIA approach is objective, repeatable, and applicable to large areas. The overall accuracy of the classification was 80% (Cohen's κ = 0.77). We used this high‐resolution vegetation classification alongside existing data on habitat condition and aquatic species' distributions to identify reaches' conservation value and restoration potential to guide management actions. Specifically, cottonwood (Populus fremontii) and tamarisk (Tamarix ramosissima) density layers helped to establish broad restoration and conservation reach classes. The high‐resolution vegetation mapping precisely identified individual cottonwood trees and tamarisk thickets, which were used to determine specific locations for restoration activities such as beaver dam analogue structures in cottonwood restoration areas, or strategic tamarisk removal in high‐density tamarisk sites. The site prioritization method presented here is effective for planning large‐scale river restoration and is transferable to other desert river systems elsewhere in the world.     

Relationships between soil parameters and vegetation in abandoned terrace fields vs. non-terraced fields in arid lands (Lanzarote,Spain): An opportunity for restoration

Over 90% of terraced fields have been abandoned on the island of Lanzarote in the last 40 years. The present work analyses the effects of abandonment on the soil and vegetation recovery of terraced field agroecosystems by comparing them with adjacent non-terraced fields in Lanzarote, Canary Islands (Spain). This information is necessary to take the appropriate management actions to achieve goals such as soil protection and biodiversity conservation. Results indicate that terraced fields display better soil quality than non-terraced ones, as shown by the significant differences found in parameters such as SAR, exchangeable Na, CaCO₃, B content, moisture content or soil depth. Moreover, the terraced fields' plant community has more species similarities with the native plant community when compared with non-terraced areas. Owing to characteristics such as deeper soils, more water capacity, lower salinity and less sodic soils, terraced soils provide better conditions for passive restoration of both soil and vegetation. Therefore, the recovery and maintenance of wall structures and revegetation with native/endemic species are proposed to promote the restoration of native systems and preserve a landscape with cultural and aesthetic value.     

表土在日本植被恢复中的应用

土壤种子库具有区域特有的物种组成和遗传特性,对维持物种多样性和种群密度起到重要作用.表土是具有植被恢复潜在能力的绿化材料.本文在参考大量日本文献的基础上,介绍了利用表土进行植被恢复的特点及分类,从表土混合比例、坡面环境、表土采集深度等3个方面归纳分析了利用表土进行植被恢复的方式,介绍了其在森林、道路、湿地、废弃地等不同类型生境中的应用.最后针对表土在植被恢复应用中存在的问题提出了今后的研究课题:应加强表土在植被恢复中的应用研究,明确绿化技术、恢复目标及表土作为绿化材料的适用性调查方法和标准,开发低成本、高效率的新型表土利用方法.     

Fauna as passengers and drivers in vegetation restoration: A synthesis of processes and evidence

Efforts to restore terrestrial woody ecosystems to former agricultural land are typically based on plant‐focused actions, often neglecting fauna. However, the processes that maintain or restore the health and integrity of these ecosystems involve many animal–plant interactions. Here, I synthesise information about these relationships and the implications for revegetation practice. Fauna have often been viewed as passengers, responding passively to plant‐focused revegetation. This view involves two surrogacy assumptions: first, that vegetation attributes can indicate habitat sufficiency for fauna; second, that animals will be capable of dispersing to the restored habitat and of establishing populations there. Habitat sufficiency depends on how resources such as food and nest sites can be indicated by vegetation attributes and how they interact with an animal's species‐specific requirements. Dispersal and establishment depend on proximity to source populations in habitat elsewhere, the type of intervening habitat and the intrinsic mobility of different species. Evidence about the effects of age, revegetation type and spatial context in relation to animal communities indicates that it can often be invalid to assume vegetation surrogacy. Fauna can also drive the developmental trajectories of floristic diversity and composition during revegetation, because animal–plant interactions frequently mediate life‐history transitions that determine seedling recruitment. Frugivore‐mediated seed dispersal is the best studied, but animals also directly influence early‐stage tree recruitment, especially through their roles in seed predation, seedling herbivory and indirectly through top‐down cascades that include large carnivores. These processes have been insufficiently recognised or studied, although some recent work highlights their significance. Intervening to alter abundances of functionally important animals could be useful in accelerating the redevelopment of woody vegetation. Further research is needed to clarify animals’ roles as both passengers and drivers during revegetation, especially manipulative experiments and innovative restoration trials, in which animals and plants are considered together from the outset.     

Natural revegetation on topsoiled mining-spoils according to the exposure

Comparative plant successional studies on derelict sites are providing significant insights into vegetation dynamics to ensure the success of future revegetation projects in these areas and, in the short-term, by using a space-for-time substitution. In this paper we describe, in relation to site exposure, vegetation development on waste rock materials covered with biologically active soil media, and compare this development with that from a previous study at the same mine (CW Spain) on non-biologically modified waste rock materials. The succession under study is faster on the North slope, as expected, and does not differ significantly from the general pattern of primary revegetation, although it was characterised by its own sequence of plant species. The topsoiling of waste increases richness and diversity from the first year of revegetation, reduces the time required for recovery of a terminal stage, and highlights the influence of slope orientation on vegetation dynamics. A total of 237 plant taxa were recorded, showing one of four patterns of change: (1) ‘pioneer’, (2) ‘intermediate’, (3) ‘late coloniser’ and (4) ‘fluctuating’.     

Murray Catchment habitat restoration: Lessons from landscape‐level research and monitoring

Native vegetation restoration and conservation works have been ongoing for three decades in the South West Slopes Bioregion of NSW's Murray Catchment. Monitoring of extensive areas of protected remnants and revegetation undertaken through a major partnership between ANU researchers and the Murray CMA shows early benefits of restoration efforts to biodiversity and helps to refine future efforts.     

Faunal response to revegetation in agricultural areas of Australia: A review

Summary   We reviewed the literature on fauna in revegetation in Australian agricultural areas. Of 27 studies, 22 examined birds, with few studies focusing on other faunal groups (four to six studies for each remaining group) and nine examined multiple groups. Existing evidence suggests that revegetation provides habitat for many species of bird and some arboreal marsupials. Species richness of birds was greater in revegetated areas that were large, wide, structurally complex, old and near remnant vegetation. Bats, small terrestrial mammals, reptiles and amphibians did not appear to benefit significantly from revegetation in the short term. Evidence to date suggests that revegetation is not a good replacement of remnant vegetation for many species. Key information gaps exist in the faunal response to (i) revegetation as it ages; (ii) different structural complexities of revegetation; (iii) revegetation that is composed of indigenous vs. non-indigenous plant species; and (iv) revegetation that is in riparian vs. non-riparian locations. In addition, little is known on the value of revegetation for declining or threatened fauna, or of the composition of fauna in revegetation. There is a need to better understand the balance between quantity of revegetation in the landscape, and the quality or complexity of revegetation at the patch scale. Based on current evidence, we recommend revegetation be conducted in patches that are large, wide and structurally complex to maximize the benefits to fauna.     

Assessing the impact of water management options upon vegetation development in drained lake side wetlands

Lake-side wetlands and their original vegetation have become rare in The Netherlands. The few remaining lake-side wetlands (also called: boezemlands) are mostly managed as nature reserves. Much attention is given to the preservation and restoration of species-rich meadows (Calthion palustris). In lake-side wetlands, both desiccation and acidification endanger the characteristic environmental conditions of these plant communities.The aim of this study was to develop guidelines for water management in different types of boezemlands. Three sites, representing different hydrological conditions, were selected. The steady-state groundwater model FLOWNET was used to describe water movement. The results of vegetation surveys were used to produce response curves for important species, giving correlations between their presence and environmental conditions (groundwater levels, soil pH).     

干旱地区斑块状植被格局形成的水分驱动机制及其研究进展

斑块状分布是植被在水分匮乏环境中长期适应的结果,其演替过程可以作为生态系统响应气候变化和人类活动产生突变的"指示器"。本文通过对斑块状植被的起源、生态水文过程及其对干旱区植被恢复的启示等方面进行综述,提出了我国干旱区植被恢复中目前尚存在的主要问题。认为斑块状植被的形成可能受气候变化、人类活动、植物自身的生物学特性及其对环境胁迫的适应等方面的影响,但不是主要因素,植被斑块和裸地斑块之间在不同空间尺度的水分再分配是其在干旱半干旱地区形成并且能够维持稳定的关键。斑块状植被是一个高效的雨水集流系统,裸地斑块是整个系统径流的"源",而植被斑块是整个系统径流的"汇",保护植被斑块的同时维持一定面积的裸地对于整个生态系统的稳定都具有极其重要的意义。斑块状植被也是一个非常脆弱的生态系统,气候的剧烈波动以及人类的过度活动都可能导致生态系统功能丧失,最终产生不可逆转的影响,因此需要加以严格保护。     

石林风景区不同石漠化人工修复方式对木本植物群落组成及种群生态位的影响

石漠化是我国西南喀斯特地区生态修复最严重的障碍,植被恢复是石漠化治理的重要途径。近50年来,我国开展了大量石漠化植被恢复的实践与研究,包括自然恢复与人工修复。但是,长期以来缺乏对已完成人工修复的植被的演替特征和修复效果的研究,而人工修复植被的效果评价能为石漠化生态修复提供理论依据与实践经验。以石林风景区中两类人工修复植被——栽植植被(PV)与飞播植被(ASV)为研究对象,以地带性自然植被(ZNV)为对照,研究人工修复植被中木本植物群落组成、群落多样性和种群生态位特征,以期揭示不同人工修复方式下的植被构成规律以及对有限资源的利用程度。结果表明:(1)在地带性自然植被、栽植植被和飞播植被3种植被类型中分别记录到木本植物92种(45科80属)、138种(50科101属)与44种(26科37属),3种植被类型中的共有种12种。(2)3种植被类型的Patrick丰富度指数与Shannon-Wiener多样性指数排序均呈现为地带性自然植被栽植植被飞播植被(P0.01),栽植植被与地带性自然植被之间的Jaccard相似性指数为0.14,飞播植被与地带性自然植被之间的Jaccard相似性指数为0.12;(3)3种植被类型中任意两者之间的生态位宽度均存在较大差异,但是清香木(Pistacia weinmannifolia)在3种植被类型中生态位宽度排位均靠前,利用资源能力较强;(4)生态位重叠程度的排序为地带性自然植被飞播植被栽植植被。综上,与地带性自然植被相比,人工修复植被物种多样性较低,但是人工修复植被的优势种中乡土植物占89.33%,乡土植物生态位较广,生态位重叠值偏低,植被较为稳定。在人工修复植被中,栽植植被的修复效果优于飞播植被。研究结果对未来喀斯特石漠化地区进行人工植被修复的物种规划与群落构建时具有重要的参考价值。     

Restoration of wetland vegetation using soil seed banks: lessons from a project in Lake Kasumigaura, Japan

The restoration of degraded wetland ecosystems and the recovery of wetland biodiversity are important global issues. Generally, wetland restoration projects include activities to recover vegetation. A promising revegetation technique is one in which soil seed banks are utilized as the source of plant recolonization. Using such a technique, a pilot project to restore lakeshore vegetation was launched at Lake Kasumigaura, Japan, in 2002. In the project, lake sediments containing the seed banks were spread thinly (∼10 cm) on the surfaces of artificial lakeshores, which were constructed in front of concrete levees and had microtopographic variations. In total, 180 species, including six endangered or vulnerable species and 12 native submerged plants that had disappeared from the above-ground vegetation of the lake, were recorded in five recreated lakeshores (total area, 65,200 m²) during the first year of the restoration. The distribution of each restored species at the sites suggested the importance of microtopographic relief for recolonizing species-rich lakeshore vegetation. Furthermore, the origin of the source seed banks affected the species composition of the restored vegetation. On the other hand, the restoration sites were subject to exotic plant invasions. Here, we report lessons learned from the Lake Kasumigaura restoration project as a contribution to the establishment of ecologically sound revegetation techniques.     

Toward a social–ecological approach to ecological restoration: a look back at three decades of maritime clifftop restoration

The sharp increase in the touristic use of the maritime clifftops in western France after WWII resulted in a concentration of activities that generated ecosystem degradation in many sites (e.g. touristic infrastructure, human trampling). Consideration of the ecological value of these sites over the past three decades has led to a shift in maritime clifftop management and consequently to numerous planning and restoration projects. Using inventories of maritime clifftop restoration projects conducted in 2007 and 2016, we identified 76 restoration projects, which allowed us to study the active and passive restoration methods used. In addition, we collected and analyzed 465 vegetation monitoring plots with an average duration of 5.6 years to understand how they were used by both scientists and nonscientists. First, we describe the social–ecological systems of these restoration projects through an analysis of their social contexts, ecological stakes, and restoration goals based on 19 semistructured interviews with restoration stakeholders. Comparing our research with similar studies in the literature reveals that the main strength of maritime clifftop restorations is a strong network between scientist and nonscientist stakeholders combined with high‐level monitoring. Finally, we underline the main challenges for the future of maritime clifftop ecological restoration: (1) the need for further study of this ecological database (e.g. to study the medium‐term effect of active restoration, continue current monitoring); and (2) the need to develop sociological studies of human uses and perceptions to improve the long‐term management of restored ecosystems.     

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain.Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas.After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert,we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water.The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition.The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession.The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.     

Vegetation changes in restored semi-natural meadows in the Turku Archipelago of SW Finland

In the Turku Archipelago of SW Finland the traditional animal husbandry dramatically decreased in 1950s after which the unused semi-natural pastures and meadows began to develop into less species rich shrub and tree communities. Restoration of some semi-natural meadows and pastures started in the late 1970s. Removing trees and shrubs, grazing, mowing, and pollarding deciduous trees were used as restoration of practises. Vegetation changes were followed from forty-one permanent sample plots established on restored areas. In this paper the data before restoration and 7–8 years after the first monitoring was analysed with parametric tests. The sample plots were divided into three restoration groups where the main restoration practises were: group 1. grazing, group 2. thinning (clearing plots from shrubs and removing some trees), group 3. thinning, mowing, and grazing (old wooded meadows). The results showed that: (1) The vegetation changed during analysed time. The number of species increased in all restored areas even though the changes were more pronounced in grazed areas and wooded meadows than in thinned areas. During restoration many common herb and grass species immigrated into the sample plots, but very few new indicator species of meadows were recorded. Most of the new species were found in few numbers in a sample plot which led to the significant increase in the number of sparse species (percentage cover < 1) in all restoration groups. The grasses benefited more from the restoration than herbs increasing their percentage cover significantly in grazed areas and in wooded meadows. In thinned areas the total percentage cover of the ten most dominant herb and grass species increased significantly. (2) The different restoration groups changed vegetation quite similarly. In grazed areas and in wooded meadows significant changes were slightly more numerous than in thinned areas. (3) The differences between the islands in vegetation changes were not pronounced. The added variance components among islands increased during restoration which probably indicated that the restoration practises as well as the species pool of the islands influenced the success of restoration.