Yusuf Serengil

Advances of air pollution science: from forest decline to multiple-stress effects on forest ecosystem services.

Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered.

Global topics and novel approaches in the study of air pollution, climate change and forest ecosystems

Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii) Linking genetic control with physiological whole-tree activity; (iii) Epigenetic responses to climate change and air pollution; (iv) Embedding individual tree performance into the multi-factorial stand-level interaction network; (v) Interactions of biogenic and anthropogenic volatile compounds (molecular, functional and ecological bases); (vi) Estimating the potential for carbon/pollution mitigation and cost effectiveness of urban and peri-urban forests; (vii) Selection of trees adapted to the urban environment; (viii) Trophic, competitive and host/parasite relationships under changing pollution and climate; (ix) Atmosphere-biosphere-pedosphere interactions as affected by anthropospheric changes; (x) Statistical analyses for epidemiological investigations; (xi) Use of monitoring for the validation of models; (xii) Holistic view for linking the climate, carbon, N and O3 modelling; (xiii) Inclusion of multiple environmental stresses (biotic and abiotic) in critical load determinations; (xiv) Ecological impacts of N deposition in the under-investigated areas; (xv) Empirical models for mechanistic effects at the local scale; (xvi) Broad-scale N and sulphur deposition input and their effects on forest ecosystem services; (xvii) Measurements of dry deposition of N; (xviii) Assessment of evapotranspiration; (xix) Remote sensing assessment of hydrological parameters; and (xx) Forest management for maximizing water provision and overall forest ecosystem services. Ground-level O3 is still the phytotoxic air pollutant of major concern to forest health. Specific issues about O3 are: (xxi) Developing dose-response relationships and stomatal O3 flux parameterizations for risk assessment, especially, in under-investigated regions; (xxii) Defining biologically based O3 standards for protection thresholds and critical levels; (xxiii) Use of free-air exposure facilities; (xxiv) Assessing O3 impacts on forest ecosystem services.

Key Indicators of Air Pollution and Climate Change Impacts at Forest Supersites

Untangling the complex effects that different air pollution and climate change factors cause to forest ecosystems is challenging. Supersites, that is, comprehensive measurement sites where research and monitoring of the whole soil–plant–atmosphere system can be carried out, are suggested as a refinement of the current monitoring and research efforts in Europe. This chapter identifies and discusses key measurements to be carried out at such supersites, with a focus on four topical subjects: the carbon, nitrogen, ozone and water budgets. This kind of holistic approach is vital to a realistic translation of the ongoing changes in climate and air quality into research on the impacts on forest ecosystems. Such an integrated effort requires a considerable use of resources at highly instrumented measurement sites and can only be achieved by building on existing infrastructures.

Ecohydrologic modelling of water resources and land use for watershed conservation

Abstract Land use land cover is an important determinant of ecohydrologic processes in watershed systems. Continued urbanization changes the very nature of ecohydrological regimes of watersheds and increases their vulnerability to flooding, soil loss, and water pollution. To integrate hydrologic risk and suitability analysis into land use decisions, we used an ecohydrologic risk criteria for land use impacts on water quality and quantity in the Riva Creek watershed located to the east of Istanbul, Turkey. Hydrological risks are modeled for each sub-watershed using a spatial analysis. A spatial quantitative assessment is used to rank sub-factors for evaluating suitability for agricultural, residential and forest operations. An expert focus group is used to quantify weights. The results revealed that about 58% of the watershed is prone to hydrologic risk in medium to severe levels. We concluded that ecohydrological evaluations should form the background of landscape assessments in watersheds. An integrated approach and spatial results can provide the basis for long-term planning.

Comparison of Rainfall-Runoff Relationship Modeling using Different Methods in a Forested Watershed

The daily rainfall-runoff relationship in an experimental watershed was modeled using a statistical method and an artificial neural network method. The estimations were examined and a performance evaluation was done. It was seen that the ANN method, FFBP (Feed Forward Back Propagation), provided closer flow estimations reproducing the shape of the observed hydrograph more realistic. The superiority of FFBP was reflected in the performance evaluation criteria. The extreme flows, i.e., high and low flows, were relatively better approximated by FFBP indicating its promise as a useful tool for hydrologic studies such as flood modeling. The Rational Method was also used, as a conventional tool, to predict the maximum discharge for selected return periods. It was found to be realistic for the forested watershed under consideration when the C coefficient was taken as 0.20 for the 10-year period.

Conversion to pine: Changes in timing and magnitude of high and low flows.

Abstract Understanding watershed responses to extreme events is important for assessing potential impacts of floods, droughts, episodic pollution, and other external driving variables on watershed resources. In this study, we combine trend and frequency analyses with paired watershed techniques to evaluate the long-term high- and low-flow data from Coweeta Hydrologic Laboratory in North Carolina, USA in an attempt to quantify and interpret responses to extreme flow events in managed and unmanaged watersheds. Two experimental watersheds were converted from mixed deciduous forest cover to pine (Pinus strobus L.) in 1957 and 1956, respectively and two others were kept untreated to serve as control watersheds. Seventy years of annual streamflow (instantaneous maximum, minimum, and mean) time series data from watersheds 1, 2, 17, and 18 were analyzed with a Mann–Whitney–Pettitt test to identify and compare change points. Mean annual streamflow increased in both watersheds for 10–12 years after harvests, but the more effective factor on the flow series was the growth of pine plantations. Maximum flows of 2-, 5-, and 10-year return periods decreased after planting pine, but there was no difference for larger flow events compared to deciduous forest. For minimum flows, pine stands were more effective compared to maximum flows as minimum flows decreased for all return periods.

Managing forests as complex adaptive systems: building resilience to the challenge of global change

when. As pointed out at the close of part three, adaptation is an urgent need. We are changing the climate system and we will have to adapt to the consequences. Part 4 is a very strong argument for more research. The authors are right to state that we need to deepen our understanding of how we are impacting the planet and also right to point out the role that scientists exploring our White Planet have played in deepening our understanding. Climate change presents huge uncertainties. Decision-makers need as much evidence as possible on which to base their decisions. We will only gather that evidence through further research. For the price the UK government is paying for an aircraft carrier that, as yet, has no aircraft and, in my view is likely to become a white elephant, a colossal amount of research into our White World could be funded. This is a fascinating, well-written book. It combines history and science and gives pause for thought as we contemplate the impact of human beings on the planet. Who should read this book? For a start every delegate to the Convention of the Parties, the governing body of the United Nations Framework Convention on Climate Change. In particular, it would make useful reading for the current Prime Minister of Australia,Tony Abbot. I would also recommend this book to the CEO of every energy company and to all climate sceptics who peddle their half-baked nonsense around the lobbies of government throughout the world. You will really enjoy this book. I have!

Effects of recreational activities on the soil and water components of a deciduous forest ecosystem in Turkey

Impacts of recreational activities on some hydrological properties of a deciduous forest ecosystem related to water production have been evaluated with an inclusive soil study, coupled with a two‐year water quality monitoring program. Spatial variations of water quality parameters did not indicate a statistically significant deterioration caused by the recreational activities in the stream water, but the effects of trampling on physical soil properties were clear. The bulk density of the soils increased with the intensity of recreation from 1.18 to 1.29 g cm−3, while the percentage of clay fraction decreased, as an indicator of erosion. The soils of the stream banks in the recreation area had reasonable saturated hydraulic conductivity values, and were affected sharply by the intensity of recreational use. The low inclination (0.5%) and the coarse texture of the soils were possibly the main factors diminishing or concealing the trampling effects not observed on the water quality of the stream passing through the recreation area.

Water quality management in the Balabandere Creek catchment

Understanding hydrological and hydrochemical processes has become increasingly more challenging with high rates of population growth and subsequent alteration of the environment. In addition to maintaining monitoring networks to assess the general state of water quality, detecting trends, and computing pollutant transport, process-level information is needed to evaluate factors that affect the transport and transformation of solutes in aquatic environments. In this study, conducted in the Balabandere Creek catchment, a monitoring program was performed in order to assess pollution sources along the creek longitudinal profile. Balabandere Creek is a typical suburban creek, located near Istanbul. Four sampling points were selected along the creek longitudinal profile, and physical, chemical and bacteriological analyses were made on grab water samples taken at 15-day intervals for seven months. This monitoring process was designed to provide basic inventory information suitable for catchment scale water quality management, and, in addition, to help to support the formulation of legal regulations for policy planning and practice. The land use in the catchment and possible nutrient sources were taken into account when considering the sampling points. The nutrient load of the first sampling point, draining the managed mixed broadleaved forest, was significantly lower than the other points (total nitrogen ?1 = 0.04, ?2 = 0.18, ?3 = 0.09, ?4 = 0.66 ppm) despite the dilution effect. Evaluation of the water quality parameters are discussed and the cumulative effects of various land use types are proposed. With the aid of this monitoring process, the catchment as a system was delineated and possible pollution sources were identified. The measures required to decrease the pollution of the creek are discussed. The situation and legislation for these kinds of problems in Turkey are also assessed.

Stream corridors as indicators of watershed land use: A case study in Istanbul

Resumen en: Riparian ecosystems as components of stream corridors provide a range of regulating ecosystem services including water production. Water quality, a compo...