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The first step in planning the actions for climate change adaptation involves performing Climate Change Vulnerability Assessment (CCVA) to vulnerable populations and ecological systems. The study aims to perform a bibliometric analysis on the CCVA research field to identify how it was structured in terms of the mostly occurring research terms and their citation impact. A set of scientific papers related to CCVA (n = 8941) were retrieved via Elsevier’s Scopus database over the period 1996–2016 using specific keywords. The search was carried out in February 2017. The number of yearly papers published in CCVA research field increased after 2006, increasing more than six times in 2016. Our co-occurrences term analysis grouped four clusters related to (i) exposure, sensitivity, and quantitative methods for assessing CCVA, (ii) adaptive capacity and qualitative approaches, (iii) CCVA integrated approaches by combining participatory methods to quantitative ones, and (iv) collaboration and participation issues related to global change. The co-citation analysis showed that highly cited research terms were related to adaptation, exposure factors, and related changes and global change. This bibliometric analysis has provided an overall picture on the CCVA research field, particularly highlighting its utility for climate change adaptation.

Soil microbial activity is recognized as an important factor affecting nitrogen (N) release from slow-release fertilizers. However, studies on the effect of size and activity of soil microflora on fertilizer degradation have provided contrasting results. To date, no clear relationships exist between soil microbial activity and the release of N from slow-release fertilizers. Hence, the aim of this study was to better understand such relationships by determining the release of N from three slow-release fertilizers in soils with different microbial activities. Soils were amended with urea-formaldehyde (UF), isobutylidene diurea (IBDU), and crotonylidene diurea (CDU). Urea, a soluble fertilizer, was used as the control. Fertilized soil samples were placed in a leaching system, and the release of N was determined by measuring ammonium-N and nitrate-N concentrations in leachates during 90 d of incubation. Non-linear regression was used to fit N leaching rate to a first-order model. In all the treated soils, N was released in the order: urea (89%–100%) > IBDU (59%–94%) > UF (46%–73%) > CDU (44%–56%). At the end of incubation, N released from CDU did not differ (P > 0.05) among soils. On the contrary, UF and IBDU released significantly lower (P

The relevance of precision agriculture produced a growth of the related literature over the years. However, a structured analysis of the published material is still missing. Thus, this study attempts to analyze the global scientific output of precision agriculture researches published during the period 2000–2016. By using a science mapping approach, mainly based on the application of network analysis tools, it was possible to investigate pivotal aspects of this research field such as publication trends, research topics and their geographical distribution. Using the Scopus database 17,756 scientific publications were retrieved from the chosen period. The number of publications increased after 2006, highlighting the vibrancy of the field. By authoring 35% of the publications, U.S.A. and China were the most active knowledge producer countries. Moreover, the generation of time resolved maps allowed us to identify agriculture engineering, computer science and agriculture studies as three main research areas characterizing precision agriculture panorama. The paper discusses the distribution of these topics at global level, among European countries and in Italy. Overall, this analysis represents the first holistic view of precision agriculture research providing valuable information for farmers, policy makers and researchers.

This paper reviews the use of stable carbon isotope analysis to monitor the results of forest ecosystems management. Special focus is given to Mediterranean coppice woodland. We used this due to the high sensitivity and spatial-temporal resolution of isotope analysis coupled with the complex attributes arising from the composite management options now used in the coppice system. A meta-analysis based on 1428 publications from 1996 to 2015 revealed three distinct clusters of related terms in research carried out to answer questions linked to the management of forests and terrestrial ecosystems namely, forest soil and forest carbon sequestration, the anthropogenic impact on plant and animal communities, and the physiological response to silvicultural practices. Much physiological research on the study of the impact of silvicultural practices on released trees has been carried out. A retrospective literature-analysis gave rise to three different functional hypotheses. The first hypothesis is that carbon isotope composition decreases after thinning, mainly due to the rapid increase in soil moisture availability and decreased competition for water and nutrients, i.e. decreasing intrinsic water-use efficiency (measured as the ratio of CO2 assimilation to stomatal conductance, A/gs). Conversely, the second hypothesis is that δ13C values increase due to the higher increase in A over gs, especially observed in sites where water is not a limiting factor. The third hypothesis was that there was no variation in δ13C due to an equal and parallel increase in both A and gs. We found that the physiology of Mediterranean coppice stands is consistent with the first hypothesis, in accordance with other analyses already performed on permanent research monitoring plots. The main finding however is that stable isotope analysis does not overlap with any of the other investigation tools in use, but actually fills a gap by providing further, effective insights into the ongoing functioning processes. Of course monitoring these processes will take on increasing importance, especially in view of the climate shift in progress.

New Poplar clones for biomass production are currently under evaluation in Italy to be cultivated in Mediterranean site conditions, where the evapotranspirative demand is not balanced by rainfall supply. The study aims to evaluate the dynamic responses of leaf gas exchanges, budding, foliar morphology and yield in three modern hybrids Poplar clones (AF2, AF6 and Monviso) under non-irrigated and suboptimal site conditions in a Short Rotation Forestry plantation of Central Italy. During the drought season, the stomatal closure was gradual in AF2 and AF6 but rapid in Monviso. These traits were associated with the best yields (expressed as dry matter) in AF2 (8.74 Mg ha−1 year−1) and AF6 (6.53 Mg ha−1 year−1) compared to Monviso (5.72 Mg ha−1 year−1). Monviso was advised as sensitive clone to summer drought even if it has showed higher photosynthetic potential traits such as earlier budding and maximum leaf area. AF2 and AF6 were advised as tolerant and moderately-tolerant clones to summer drought as they maintained higher and relatively-higher stomatal conductance (gs) values over a growing season, summer photosynthetic assimilation rates (A) and intrinsic water-use efficiency (A/gs ratio) compared to Monviso, respectively. We pointed out the occurrence of main physiological processes (budding, maximum and minimum gs, maximum leaf area) to highlight the key-periods leading the growth under these site conditions by identifying the air temperature thresholds and precipitation patterns along a growing season. We provided recommendations to Italian Poplar practitioners for cultivations of these clones in Mediterranean areas affected by summer drought.

The presence and acceptance rates of hypotheses of papers in seven major soil journals were analyzed between 2001 and 2013. The aim of the study was to quantify the testing of hypotheses in soil science and investigate how it evolved over time. The journals were Applied Soil Ecology , Biology and Fertility of Soils , European Journal of Soil Science , Geoderma , Plant and Soil , Soil Biology and Biochemistry and Soil & Tillage Research . In total 15,344 papers were published by the seven journals over that period. Of a sample of 620 papers, 74% tested one hypothesis, 20% tested two or more hypotheses and 6% proposed a hypothesis. In total 66% of the all tested hypotheses ( n = 783) were accepted, and the acceptance rate for the seven journals was more or less constant over time. A single hypothesis is more likely to be accepted (75%) compared to research with multiple hypotheses (55%). Although there was some difference between journals, it was concluded that acceptance rates of hypotheses in soil science are relatively low compared to other scientific disciplines.

International audience; & Context Harvesting of Mediterranean oak coppice forests has been progressively suspended on a share of cover over the last decades. Positive growth trend in outgrown coppices no longer harvested on short rotations now drives natural forest restoration on wide areas, and it represents a potential carbon sink in view of global warming. & Aims Our goals were to estimate carbon (C) and nitrogen (N) content per compartment in two deciduous oak outgrown coppice forests, aged differently and growing under unequal site quality, to verify whether C concentration across compart-ments is in agreement with the conventional conversion rate of 0.5. & Methods Ecosystem C and N pools were assessed by multiplying the whole coppice mass (combining specific al-lometric functions, root-to-shoot ratio, and soil sampling) by respective C and N concentrations. & Results The results point out that the largest percentage of N was stored in 15-cm topsoil (84.06 and 73.34 % at the younger and older site, respectively), whereas the proportion of organic ecosystem C pool was more variable, as a consequence of the amount and allocation of phytomass. We found that, in most cases, C concentration was less than the conventional conver-sion rate of 0.5, especially in deadwood, O layer, and root compartments. & Conclusion The findings provide further knowledge of C and N storage into these new built-up forest types and the evidence that a detailed analysis may get higher accuracy in the pools estimate, producing a more reliable outlook on dynamics and climate change mitigation ability of these systems.

It has been reported that root exudates of Sorghum bicolor can inhibit nitrification in a bioassay using Nitrosomonas, and methyl 3-(4-hydroxyphenyl) propionate (MHPP) was identified as one of the nitrification inhibiting compounds. Therefore, we have investigated the effects of this compound on nitrogen dynamic, potential nitrification activity and on soil microorganisms. We conducted soil incubation experiments using synthetic MHPP to evaluate its effect on changes in inorganic soil nitrogen pools, on nitrification activity and on abundance of ammonia-oxidizing bacteria and archaea. Addition of MHPP at two concentrations equivalent to 70 and 350 μg C g−1 soil was compared to glucose as a carbon source and to the commercially available nitrification inhibitor dicyandiamide (DCD). Soil amended with the high dose of MHPP and with DCD showed reduced nitrate content and low nitrification activity after 3 and 7 days of incubation. This was mirrored by a 70 % reduction in potential nitrification activity compared to a nitrogen-only control. None of the incubation treatments affected non-target microbial counts as estimated by 16S rRNA gene copy numbers, however, the high dose of MHPP significantly reduced the abundance of ammonia-oxidizing bacteria and archaea. These findings suggest that MHPP is capable of suppressing nitrification in soil, possibly by reducing the population size and activity of ammonia-oxidizing microorganisms.

International audience; Building research capacity in forest science has been recognized internationally as important in order to produce a sound evidence basis for decision-making in policy and practice, even if there is currently little evidence on how to measure and consequently spread progress and innovations resulting from forest research, especially in a fragmented region such as the Mediterranean. The paper aims at establishing a framework from 79 institutions undertaking forest research across thirteen Mediterranean countries for measuring their research capacities and the potential they reached to disseminate results and innovations in forest research. The methodology adopted makes use of common indicators thereby allowing comparisons across countries as regards the following: (i) research lines performed in forest research, (ii) budget generated by forest projects, (iii) overall full budget spent for forest research, (iv) number of forest projects implemented, (v) number of total researchers, permanent staff and non-permanent staff deployed in forest research, and (vi) ISI papers published in forest subjects. Forest research capacities have tentatively been clustered to find similarities or dissimilarities across countries, in order to identify possible partnerships to be reached and to highlight causal indicators that affected the clustering. The paper findings contribute to address how capacity for forest research in the Mediterranean area is developed and how to measure and evaluate the performances of research and innovation systems. They provided further contributions to existing debates in the literature in order to foster research collaboration in the forest sector, knowledge mobilization, innovation and proposals/policies for a common research framework in the European forest sector.

Human activity has had the single largest influence on the global nitrogen (N) cycle by introducing unprecedented amounts of reactive-N into ecosystems. A major portion of this reactive-N, applied as fertilizer to crops, leaks into the environment with cascading negative effects on ecosystem functions and contributes to global warming. Natural ecosystems use multiple pathways of the N-cycle to regulate the flow of this element. By contrast, the large amounts of N currently applied in agricultural systems cycle primarily through the nitrification process, a single inefficient route that allows much of the reactive-N to leak into the environment. The fact that present agricultural systems do not channel this reactive-N through alternate pathways is largely due to uncontrolled soil nitrifier activity, creating a rapid nitrifying soil environment. Regulating nitrification is therefore central to any strategy for improving nitrogen-use efficiency. Biological nitrification inhibition (BNI) is an active plant-mediated natural function, where nitrification inhibitors released from plant roots suppress soil-nitrifying activity, thereby forcing N into other pathways. This review illustrates the presence of detection methods for variation in physiological regulation of BNI-function in field crops and pasture grasses and analyzes the potential for its genetic manipulation. We present a conceptual framework utilizing a BNI-platform that integrates diverse crop science disciplines with ecological principles. Sustainable agriculture will require development of production systems that include new crop cultivars capable of controlling nitrification (i.e., high BNI-capacity) and improved agronomic practices to minimize leakage of reactive-N during the N-cycle, a critical requirement for increasing food production while avoiding environmental damage.

Screening numerous genotypes for nitrification inhibition activity provides first evidence that root exudates of rice can slow the nitrification of ammonium to nitrate in soil. This offers promising possibilities for exploiting molecular and genetic tools to improve nitrogen use efficiency by inhibiting wasteful nitrification., Background and aims Nitrification is an important process in soil--plant systems for providing plant-available nitrate (NO3−). However, NO3− is less stable in soils compared with ammonium (NH4+) and is more easily lost through leaching, runoff or denitrification. This study tested whether biological nitrification inhibition (BNI) activity is present in the root exudates of rice (Oryza sativa) and also the extent of variation between different genotypes. Methodology The BNI activity of root exudates was estimated by a bioluminescence assay using a recombinant Nitrosomonas europaea strain. Afterwards, the effect of a single application of concentrated root exudates and that of exudates deposited in the rhizosphere soil was tested on BNI using soil incubation. Soil was added with (NH4)2SO4 and water to reach 60 % of the water-holding capacity and incubated at 30 °C for different periods. Amounts of NH4+ and NO3− were determined using a continuous-flow auto-analyser. Principal results In an initial screening experiment, BNI activity in the exudates of 36 different rice genotypes was evaluated using a bioassay based on a recombinant Nitrosomonas strain. Significant genotypic variation was detected with the upland cultivar IAC25 demonstrating consistently high BNI activity, while modern lowland varieties like Nipponbare or IR64 exhibited lower activity. Subsequent experiments ruled out the possibility that BNI activity is simply due to non-specific (solute) leakage from roots. Soil incubation studies with concentrated root exudates of IAC25 showed significant reductions in NO3− formation. This effect was confirmed by detecting lower NO3− levels in incubation experiments using rhizosphere soil obtained from IAC25. Conclusions Our results provide first evidence that root exudates of rice can reduce nitrification rates in soil. Having shown this for a model crop, rice, offers possibilities for further exploitation of this phenomenon through molecular and genetic tools.