Recovery Of Riparian Vegetation Research Articles

Assessing the Feasibility and Socioecological Benefits of Climate-Smart Practices at the Watershed Scale

Resource allocation in climate-smart productive practices depends on the explicit recognition and accountability of the expected costs and benefits in socioeconomic and ecological terms. This study assessed the private and social costs and benefits of 10 practices compatible with the transition to sustainable agricultural practices under an integrated landscape management (ILM) approach. First, the financial and economic viability of the alternatives was evaluated with a cost-benefit analysis. Then, the potential contribution of these practices in terms of carbon sequestration and landscape connectivity was determined in an ILM scenario where at least three practices (live fences, isolated trees in pastures, and riparian vegetation recovery) could be implemented and assessed at the watershed scale. These practices were evaluated in three Mexican pilot watersheds with contrasting biophysical and sociocultural contexts but with high importance in biodiversity conservation and cattle production. The results showed that most climate-smart practices are viable in the medium and long term from a private standpoint. However, more significant benefits are achievable over a shorter period when social co-benefits are included. The results could contribute to decision-making in terms of public policy, providing evidence of the financial and economic feasibility of the analyzed climate-smart practices that also have ecological benefits. In this sense, decision-makers who promote such practices have more arguments to seek funding for implementation.

The Effects of Implementing Three Climate-Smart Practices with an Integrated Landscape Approach on Functional Connectivity and Carbon Storage

Climate-smart practices are actions that can be implemented without affecting agricultural activities and that can promote these activities, generating direct and indirect benefits in ecosystem services provision and increasing agricultural productivity and private income. The present study evaluated the effect of three climate-smart actions (establishment of isolated trees, recovery of riparian vegetation, and implementation of live fences) on increased functional landscape connectivity and carbon storage. Three scenarios with rates of participation ranging from 5 to 100% were tested in two watersheds with different degrees of conservation and a high priority for national food production in Mexico. The main results suggest climate-smart practices positively impact landscape connectivity and carbon sequestration. However, the improvement in landscape connectivity mainly benefits species of short displacement (50–100 m), and the increase in carbon storage is directly linear to the area implemented in these practices. Also, the effectiveness of the modeled actions depends on the landscape structure, which was implemented with the highest benefits in watersheds with intense agricultural activity. The findings can support decision-makers in selecting the best strategies to increase landscape connectivity and carbon sequestration in productive landscapes.

Effects of Restoration and Conservation of Riparian Vegetation on Sediment Retention in the Catchment Area of Corumbá IV Hydroelectric Power Plant, Brazil

Vegetation cover and land use are important factors related to the capacity of ecosystems to provide soil loss regulation and sediment retention services, which are highly relevant for sediment management in watersheds draining into reservoirs with multiple water uses. One way to ensure the protection and recovery of vegetation by landowners in Brazil is the implementation of the federal Native Vegetation Protection Law (NVPL), which designates environmentally sensitive areas as Areas of Permanent Preservation (APPs), aiming to conserve water resources and prevent soil erosion. The benefits of riparian vegetation in the catchment of Corumbá IV Hydroelectric Power Plant (HPP), located in the Brazilian Cerrado, were analyzed considering landscape reconfigurations from a baseline condition (year 2011) in order to account for the recovery of riparian vegetation by the agricultural sector, as foreseen in the NVPL. The Sediment Delivery Ratio (SDR) model from the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) package was used to map and quantify variations in sediment export and sediment retention throughout the catchment. The reduction in annual sediment export in the drainage basin of the Corumbá IV reservoir reached −27% in the scenario where the total deficit of riparian APPs occupied by pasture or agriculture in the baseline map (41.000 ha) are recovered. While 14% of riparian APP are occupied by crops versus 86% occupied by pasture in the drainage basin of the Corumbá IV HPP, the recovery of riparian zones occupied by agricultural activities resulted in the greatest benefits in sediment retention for the reservoir. The methodology employed in this study can support the prioritization of sectoral efforts for the restoration and conservation of native vegetation, considering the highest returns in benefits perceived by water users affected by sediment input in reservoirs. The study’s results reinforce the importance of conserving vegetation in riparian areas and their surroundings for sediment retention, highlighting the role of these areas as assets in providing water-related ecosystem services. For future developments, it is suggested to assess the interconnections among the energy, water, and food sectors to better understand the barriers and challenges to the maintenance and improvement of water-related ecosystem services in the catchment area of Corumbá IV HPP.

Dam inundation duration as a dominant constraint on riparian vegetation recovery

The identification of limiting factors is essential for the ecological restoration of riparian ecosystems degraded by the damming of rivers, but remains unclear. Here, we quantitatively assessed the relative importance of environmental factors and revealed the main limiting factors for riparian vegetation restoration and their influencing mechanisms, using riparian plant and environmental data of seven large reservoirs in southwest China. We found that inundation duration had a significantly greater effect on riparian vegetation distribution, cover and diversity than environmental factors such as inundation depth, rainfall, humidity, temperature, sunshine hours, aspect, slope, surface relief, soil pH, available nitrogen (AN), available phosphorus (AP), and available potassium (AK); vegetation cover, species richness, complexity and dominance were highly significantly negatively correlated with inundation duration (p < 0.01); inundation for 5 months is close to the tolerance limit of most plants and poses a significant limiting effect on the vegetation restoration in the reservoir riparian. Therefore, the inundation duration should be highlighted in riparian vegetation restoration. Meanwhile, incorporating the riparian inundation into the river ecological scheduling objectives to shorten the inundation duration and thus radically alleviate the limitation is a new opportunity for vegetation restoration in the reservoir riparian.

Trends in post‐1950 riparian vegetation recovery in coastal catchments of NSW Australia: Implications for remote sensing analysis, forecasting and river management

AbstractExtensive riparian vegetation clearance occurred in many rivers of southeastern Australia throughout the 19th and 20th century, post colonisation. With improvements in river management practices, coincident with a period of minimal flooding, vegetation recovery of riparian corridors has been occurring since the 1980s in all coastal catchments of New South Wales (NSW). However, the catchment‐by‐catchment spatial pattern and temporal trends, trajectories and rates of vegetative recovery remain unknown. We reconstruct a 70‐year time series of change in riparian vegetation coverage for all rivers in coastal catchments of NSW, utilising historical aerial imagery, Landsat and Sentinel data and a manual digitisation and machine learning method. We quantify and statistically analyse decadal trends in woody and non‐woody vegetation coverage along 19 485 km of stream length in 20 catchments. Across the region, there has been, on average, a 40% increase in vegetation coverage along riparian corridors since the 1950s, with some catchments increasing towards a current day coverage of between 60% and 80%. However, the trends vary by subregion and by catchment. An early logarithmic increase occurred up to 2004 on the North coast, and a recent and accelerated exponential increase since 1995 has occurred on the South coast. After a steep initial increase, riparian corridor vegetation coverage has fluctuated on the Central coast since about 1995. We used these linear, exponential and logarithmic regressions to undertake preliminary forecasts of possible future timeframes of riparian vegetation change, based on several climate, management and natural disaster disturbance scenarios. If the current trend continues, riparian vegetation coverage can reach 70% across the region by 2055. However, if management practices change or catastrophic disturbance events such as fire and flood occur, increases in riparian vegetation coverage could be set back by up to 30 to 40 years.

The hydrochorous dispersal of plant propagules in a giant river reservoir: Implications for restoration of riparian vegetation

Abstract The riparian vegetation of many rivers around the world is impacted by flow regulation for hydropower. Water levels behind dams are being raised to generate electric energy, forming river reservoirs. River regulation has a large impact on the riparian vegetation, which influences both the adjacent aquatic and terrestrial ecosystems. Therefore, the restoration of degraded riparian vegetation in river reservoirs has been of increasing research interest. Propagules dispersed from connected tributaries via water (hydrochory) are considered a vital source for the recovery of riparian vegetation in regulated rivers. However, the hydrochorous dispersal of plant propagules in river reservoirs is unclear. We explored the dispersal distance and deposition patterns of hydrochorous propagule mimics in three tributaries that are regulated by the Three Gorges Reservoir (TGR) in China. In eight out of nine release experiments, 95% of propagule mimics were found within 3 km downstream from the release points. Cumulative wind speed was the most important factor affecting the dispersal distance of propagule mimics in the TGR. However, the dispersal distance of propagule mimics was not significantly affected by water‐level variation and channel sinuosity. Variations in water level strongly affected the deposition pattern of propagule mimics, with only 6.6% of the propagule mimics stranding on the riparian zones under raised water level and 83.8% stranding under declined water levels. The majority of stranded propagule mimics were deposited at gentle slopes (0–20°). Synthesis and applications. Our results suggest that the majority of propagules that enter river reservoirs via water would be retained within the first few kilometres. Wind and water level variation are the main factors determining the dispersal distance and deposition pattern of propagules. Our findings have applications for riparian vegetation restoration in river reservoirs. The vegetation in steep riparian zones distant from free‐flowing tributaries should be the priority for restoration actions because these areas receive limited hydrochorous propagules. The plant biodiversity and hydrological connectivity of connected tributaries, which is an important propagule sources, should be protected. The seasonal dominant wind pattern should be considered when evaluating the importance of tributaries as the source of hydrochorous propagules for river reservoirs.

Fire effects on riparian vegetation recovery and nutrient fluxes in Brazilian Cerrado

AbstractFire can change gallery forest vegetation structure, thereby altering nutrient fluxes between terrestrial and aquatic ecosystems. In Brazilian savannas, which are fire‐prone ecosystems, the fire regime is changing due to human activities such as converting native vegetation to farmland and urban areas. Uncontrolled wildfires in these savannas can reach gallery forests, which are more sensitive to fire impacts, leading to concerns about the effects of fire on gallery forest vegetation structure and freshwater ecosystems. We analysed the relationships between fire severity (the degree to which the fire has changed an area), percentage of burned area, variation in precipitation with gallery forest and savanna vegetation structure recovery and input of nutrients (NH4, , and ) to streams for 16 months after a fire event in five watersheds associated with small streams. One year after the fire, vegetation recovery (NDVI) was lower in gallery forest areas than in savanna woodlands, despite the more severe fires in savannas. The short‐term effects of fire on gallery forest vegetation included increased nitrate concentrations in streams, which were also influenced by increased precipitation and the extent of the burned area. The nutrient inputs into the stream stabilized within 1 year. However, gallery forest vegetation did not fully recover at that time and may continue to alter the functioning of the aquatic ecosystem. Together, these results demonstrate the need for an integrated fire management plan that considers both gallery forests and the surrounding savannas in the landscape to address consequences to aquatic ecosystems.

Assessing Restoration of Ecosystem Functioning in Brazilian Subtropical and Tropical Streams

AbstractRivers and streams provide many ecosystem services, including provision of food, water purification, and nutrient abatement. Ecosystem functioning, the set of processes that regulate the fluxes of energy and matter, is the backbone of ecosystem services. A myriad of human impacts affects the functioning of running waters. To reduce these impacts, strategies for conservation and recovery of riparian vegetation, as well as direct interventions for stream restoration, have been carried out. However, these actions have been more limited in sub/tropical than in temperate regions. Based on case studies from southeastern Brazil and comparisons with their temperate counterparts, we illustrate and discuss how restoration of riparian canopy cover and stream reconfiguration through the addition of wood can influence two key ecosystem processes: nutrient retention and metabolism. Our findings indicate that the distinctive environmental features of the sub/tropical climate strongly shape the effect of stream restoration on ecosystem functioning. However, as in the temperate climate, effects are rarely monitored for a long time after the restoration, indicating the need for their longer‐term assessment. Understanding how restoration evolves over time to impact the functioning of sub/tropical streams is fundamental for the management and conservation of these strategic water bodies and the relevant ecosystem services they provide.

Reduction of sediment yield by riparian vegetation recovery at distinct levels of soil erosion in a tropical watershed

ABSTRACT Riparian vegetation plays an important role in sediment retention, thus reduces sediment yield in watersheds. The Brazilian Forest Law (Law 12,651/2012) requires maintenance of fixed-width buffers of riparian vegetation but allows the continuity of agriculture, livestock, and forestry farming activities in some parts of the Areas of Permanent Preservation (APP). This paper aimed to evaluate sediment reduction by recovering the APPs with vegetation strips of permitted widths (5, 8, 15, and 30 m), as per the Forest Law. We considered three land use scenarios that present distinct erosion rates - predominance of areas with forest cover, pasture, and agriculture. The Soil and Water Assessment Tool (SWAT) model was used to simulate sediment yield in these scenarios at the Jundiaí-Mirim Watershed in São Paulo, Brazil. The SWAT was calibrated and validated for monthly streamflow. We obtained statistical indices for the processes of calibration and validation, respectively, as: NS = 0.77 and 0.70, PBIAS = -10.2 and -12.5, and RSR = 0.48 and 0.55. The highest reduction in sediment yield (30%) was observed with the total recovery of the APPs (vegetation strips of 30 m) in the current land use scenario. The recovery of the APPs with vegetation strips of 5, 8, and 15 m yielded sediment reduction below 10% in the alternative land use scenarios. The APP strips with reduced recovery maintained high rates of sediment yield. Additionally, even with a total recovery of the APP it is necessary to adopt soil conservation practices throughout the basin’s agricultural area to minimize the impacts on water resources.

Combined effects of an anthropogenic (forest harvesting) and natural (extreme rainfall event) disturbance on headwater streams in New Zealand

Abstract Although extreme hydrological events are a natural component of river ecosystem disturbance regimes, their frequency is predicted to increase with climate change. Anthropogenic activities have the potential to exacerbate the impact of such disturbances but there are few studies on the combined effects of both anthropogenic and extreme hydrological disturbances on stream ecosystems. We investigated the recovery of stream ecosystems over a 5‐year period following the impact of an anthropogenic (forest clear‐cut harvesting) and an extreme rainfall disturbance (estimated one‐in‐100 year average return interval) that generated debris flows in three headwater streams in New Zealand. Initially, most of the riparian vegetation was eliminated and showed little recovery 1 year later. Subsequent riparian recovery was led by wind‐borne, light‐demanding, pioneering exotic weed species, lengthening and altering the long‐term successional and recovery trajectories to a pre‐disturbance composition of indigenous shrubs. Stream shade, water temperature, and habitat had largely recovered after 5 years. However, the contribution of large wood to channel morphology and in‐stream habitat was compromised due to diminished wood supplies in the stream channel and a hiatus in up‐slope wood inputs until the riparian vegetation re‐establishes and the next crop of trees matures. After an initial decline, most indigenous fish taxa thrived in the post‐disturbance conditions, with significant increases in densities and biomass. The more sensitive fish taxa were scarce or absent, particularly those taxa that prefer pools with overhead and in‐stream cover provided by riparian vegetation and wood. Recovery of these taxa was outside the time frame of this study. Riffle dwelling fish communities were more resilient than pool dwelling fish communities. Invertebrate densities showed a similar response to fish. Post‐event invertebrate community composition differed from that typically found in post‐harvest headwater streams, comprising comparatively lower proportions of Chironomidae, Oligochaetes, and Mollusca taxa, and higher proportions of Trichoptera taxa. Progression toward pre‐event community composition was evident 5 years after the event. The compounding effect of forest removal from harvesting, along with riparian vegetation and wood removal by debris flows, lengthened the recovery of riparian vegetation and wood supplies with cascading effects on in‐stream habitat and biological communities.

Riparian vegetation recovery in a 23 year chronosequence of clear-cuts along boreal headwater streams

Recovery of understory vegetation after clearcut harvesting has received much attention but little is known about the recovery of riparian vegetation after forest harvesting along headwater streams, despite the critical role vegetation plays in the protection of biodiversity and water quality. We investigated the impacts of clearcut harvesting on riparian plant communities and their recovery along headwater streams in boreal mixedwood forests of northwestern Ontario, Canada. We studied 30 headwater streams (width 1–3 m), 24 in clearcut sites harvested 3–23 years previously and 6 streams in reference 90–100 year-old mature (unharvested) forests. Each stream was studied at two locations: (i) within clearcut areas and (ii) within the downstream unharvested locations (at the buffer zones) of the larger stream into which the headwater streams flow. We quantified species richness, abundance, diversity and evenness of riparian understory vegetation at each site. We used a nested model and Nonmetric Multidimensional Scaling (NMS) to examine the effect of years since clearcut (age) on understory plant community change. We assessed the number of original, newly recruited and locally eliminated species based on species presence/absence data from the sampled quadrats in clearcuts, downstream unharvested forests and reference forests. We found that clearcut harvesting had no immediate impact on overall species richness or diversity, but it was associated with changes in species composition. The post-harvest habitats were often dominated by ruderal invasive species. Some late-seral species were locally eliminated and showed no sign of recovery 23 years after harvesting. We conclude that although clearcutting along headwater streams does not affect the overall species diversity, it changes species composition by locally eliminating some understory plants, which in turn may cause significant change in the ecological services they provide. Hence, it is important to recognize the sensitivity of headwater systems during forest harvesting and subsequent vegetation recovery. Avoiding ground disturbance in head water systems during forest management, careful selective/partial harvesting in riparian areas and seeding of fast growing native plants immediately after clearcutting may help mitigate potential adverse effects of forest management in headwater systems.

Importance of landscape context for post‐restoration recovery of riparian vegetation

Abstract We tested whether the recovery of riparian vegetation along rapids that have been restored after channelisation for timber floating can be predicted based on floristic and geomorphic characteristics of surrounding landscape units. Our study was located along tributary stream networks, naturally fragmented in rapids, slow‐flowing reaches, and lakes (i.e. process domains), in the Vindel River catchment in northern Sweden. We tested whether landscape characteristics, specifically to what extent the geomorphology (affecting local abiotic conditions), species richness, and species composition (representing the species pool for recolonisation), as well as the proximity to various upstream process domains (determining the dispersal potential), can predict post‐restoration recovery of riparian vegetation. Our results indicate that post‐restoration recovery of riparian vegetation richness or composition is not strongly related to landscape‐scale species pools in these streams. The restored rapids were most similar to upstream rapids, geomorphically and floristically, including plant traits. Species richness of adjacent landscape units (upstream process domains or lateral upland zone) did not correlate with that of restored rapids, and proximity of upstream rapids or other process domains was only weakly influential, thus diminishing support for the hypothesis that hydrochory or other means of propagule dispersal plays a strong role in riparian vegetation community organisation after restoration in this fragmented stream network. We conclude that, in these naturally fragmented stream systems with three discrete process domains (rapids, slow‐flowing reaches and lakes), hydrochory is probably not the main predictor for short‐term riparian vegetation recovery. Therefore, other factors than landscape context can serve in prioritising restoration and, in these systems, local factors are likely to outweigh landscape connectivity in the recovery of riparian vegetation.

Water provisioning improvement through payment for ecosystem services

We assess whether a Payments for Ecosystem Services (PES) programme met its objectives of reducing soil erosion and yielding water in an environmental protected area, the Guariroba River Basin, Midwestern Brazil. We measured rainfall and water discharge throughout 2012 and 2016. During the same period, soil and water conservation practices were performed in the basin, such as: building level terraces and riparian vegetation recovery. We separated streamflow into baseflow and direct runoff, then we evaluted the baseflow index that indicated that groundwater significantly contributes to total flow. Therefore, to investigate the effects on streamflow, we performed a trend analysis in the baseflow time series using the Mann-Kendall test. In addition, we analysed the efficiency of soil erosion regulation practices over time, considering the total payment and the trends found in the baseflow. Whereas precipitation records present a decreasing trend (1 mm month−1), baseflow tends to increase by 0.018 m3 s−1 in the same period. Our findings show that soil conservation practices performed in the basin increase baseflow and also provide a better resilience to endure extreme events such as drought based on an increase in forest areas and soil conservation practices such as level terrace.

Survival of Saplings in Recovery of Riparian Vegetation of Pandeiros River (MG)

ABSTRACT This study monitored the survival of saplings planted according to different recovery models in a riparian forest of the Pandeiros river (Januaria, MG). The models consisted of planting the saplings in lines of 2 or 4 m with presence (T2S and T4S, respectively) or absence of direct seeding (T2 and T4, respectively). We planted 16,259 saplings of 17 botanical families, 32 genera and 33 species. The saplings, in general, presented a survival rate after one year of 34.4% (±1.8). The species with highest survival rates were Jacaranda brasiliana, with 85.0% (±13.5) of survival, Anadenanthera colubrina, with 70.1% (±7.0), and Triplaris gardneriana, with 69.3% (±9.1). Survival did not vary between the models tested, probably due to the short evaluation period (12 months).

Diagnóstico de degradação do Ribeirão Candidópolis, Itabira (MG): uma contribuição para propostas de restauração

A Bacia Hidrográfica do Ribeirão Candidópolis, localizada no município de Itabira (MG), é a principal fonte de abastecimento de água bruta para o Sistema Pureza, que fornece água tratada para uma parcela significativa da população urbana desta cidade. Apesar da importância do Ribeirão Candidópolis para o município, nos últimos anos este vem sofrendo com o manejo inadequado do solo na sua bacia. Dessa forma, este trabalho visou elaborar o diagnóstico das condições ambientais e fluviais de um trecho do Ribeirão Candidópolis a partir da observação e avaliação de indicadores de degradação e estabelecer propostas para a sua restauração. Assim, verificou-se que o estado de degradação do Ribeirão Candidópolis no trecho analisado pode ser classificado como “médio” com relação aos seus aspectos físicos, enquanto a qualidade ambiental recebeu a pior avaliação, resultante, principalmente da escassez ou ausência de mata ciliar. Dentre as técnicas de restauração a serem empregadas destaca-se a recomposição da vegetação ripária por meio da implementação de zonas de tamponamento e a utilização de biomantas ou pneus, aliada à recomposição vegetal, para controle dos processos erosivos observados. Nesse cenário é imprescindível a elaboração de estudos e proposição de medidas para a restauração do ribeirão visando a manutenção da qualidade e quantidade de água, sobretudo para fins de abastecimento público.

Short‐term vegetation recovery after alien plant clearing along the Rondegat River, South Africa

The outcomes of ecosystem restoration projects should be periodically monitored to inform subsequent adaptive management decisions. In 2012, a project was begun to remove both invasive alien plants and fish from the Rondegat River in South Africa. Although the initial post‐intervention dynamics of aquatic fauna have been documented, the results of the simultaneous clearing of dense riparian stands of alien trees and shrubs have not been reported. We examined native riparian vegetation recovery over 3 years after alien plant clearing. We documented increased cover of native riparian shrubs, but a simultaneous increase of alien and native weedy grass cover. Secondary invasions, especially by grasses, can have strong effects on ecosystem dynamics and achieving the goals of restoration may therefore require additional active management. Our findings provide an initial baseline reference for future monitoring and adaptive management decisions.

Controlling Purple Jewelweed (Impatiens glandulifera): Assessment of Feasibility and Costs

We experimentally tested the feasibility of a control campaign of purple jewelweed (Impatiens glandulifera), an exotic invasive species in Europe and North America. We evaluated the amount of time and money required to control the plant along riverbanks, with particular attention paid to the recovery of riparian vegetation following hand pulling and bagging. Work time was directly and significantly related to stem density and fresh biomass of the invader, but the relationship was stronger for density. Density and biomass were strongly reduced by the first hand-pulling operation from a mean of 45 to 2 stems m−2 and from a mean of 0.95 kg m−2 to nearly zero, a good performance but not enough to negate the need for a second hand pulling later in the summer. A single hand pulling significantly reduced the cover of purple jewelweed from to 30% to 7%. Riparian vegetation disturbed by the first hand pulling largely recovered during the following 30 d. Expressed over an area of 1 ha, the total amount of time required to control purple jewelweed is 1,400 work hours over 2 yr, or a minimum investment of Can$21,000 (US$17,000). Although controlling a well-established purple jewelweed population is expensive, to properly evaluate the benefits, we must also consider the costs of soil erosion caused by this species.

Assessing Restoration Outcomes in Light of Succession: Management Implications for Tropical Riparian Forest Restoration

Today there is a wide variety of approaches on how to determine when a river restoration project can be considered ecologically successful. The limited information on river restoration responses renders this practice a subjective component of river management. We aimed to contribute to this issue by assessing the ecological outcomes of a restoration project conducted in Quebrada Chiclana, a first-order tropical stream located in the headwaters of the Rio Piedras in the city of San Juan, Puerto Rico. We focused on the reforestation component of the restoration project using current structure and composition of riparian vegetation as an indicator of restoration success. Recovery of riparian vegetation was studied eight years after restoration using a forest succession approach. We conducted a vegetation census and measured structural variables on vegetation at restored and nearby reference areas. We encountered a riparian vegetation community composed of 35 tree and 84 non-tree species. The non-native trees tall albizia ( Albizia procera ) and African tuliptree ( Spathodea campanulata ) were the most abundant tree species within the study area. We observed 11 out of the 16 woody species initially proposed in the reforestation plan but with lower tree density than proposed. Even though we demonstrate that the river restoration project has not yet met its reforestation objectives, our results show recovery of the vegetation community in the impacted area has occurred through natural succession.

Modelling future scenarios to improve woodland landscapes for birds in the Mediterranean

Agro-silvo-pastoral systems occupy much of the Mediterranean region. Promoting landscape heterogeneity in these systems is a potentially valuable management strategy to enhance woodland biodiversity. We evaluated the effects on birds of managing patches of olive groves and riparian galleries to promote heterogeneity of these systems in Portugal.For a large cork oak woodland we (i) used nesting season bird density estimates and habitat descriptors to generate suitability models for each studied species; (ii) identified areas suitable to establish new patches of riparian galleries and olive groves, and used this information to (iii) generate scenarios maps with different levels of cover of both habitats. Finally, (iv) the model of each bird species was applied over the future scenarios to estimate potential changes in its distribution and abundance.Future scenarios with greater availability of riparian vegetation resulted in major increases in projected populations of seven of the 21 studied species, but gains with increases of olive groves were predicted in just three species. Bird species predicted to increase the most with the recovery of riparian vegetation are presently among the least abundant in the region. Restoring riparian galleries would be highly beneficial for birds, whereas promoting traditional olive groves would have lower conservation implications.The methodology used proved helpful to select areas particularly appropriate for habitat management, generate simulated landscapes incorporating this management, and predict the population and spatial responses of species to these simulated scenarios, thus having a good potential to guide conservation management. Moreover, our results indicate that simple management measures should have substantial positive effects on the bird community of oak woodlands, without compromising the essential economic return of the system.

Is the riparian habitat creation an effective measure of plant conservation within the urbanized area?

The study presents results of habitat creation and riparian vegetation recovery in artificial oxbow lakes in urbanized area within the large river valley. The investigation of open water, rush and wet meadows flora and vegetation in three ponds located in the city centre of Opole was conducted in years 2001–2013. Oxbow lakes were constructed as a compensation measure and no vegetation was transplanted into the ponds on purpose. 13-years observation showed that (1) the red-listed species are able to spontaneous reoccurrence after habitat restoration, but they can thrive only in first years of oxbow lakes recolonisation process, (2) there are some restoration constraints, especially in relation to Phragmites australis and Nuphar lutea expansion, but alien species invasions were insignificant and (3) the species number and vegetation cover was constantly increasing during the recolonisation process in recreated oxbow lakes. The dynamic of vegetation was considerable, especially in first 6 years of experiment when the significant increase in diversity and richness of native plant species was observed. After that time, the increasing expansion of P. australis and N. lutea was noted causing the decline of several species and vegetation types. So, restoring just the environmental conditions may be sufficient for a limited period of time only. Strong disturbances, much intense that moderate inundations, imitating disastrous flooding within the valley each 10–13 years are need to maintain the ecological niches for river corridor and riparian species.