Integration of different environmental valuation methods to estimate forest degradation in arid and semi-arid regions

Many factors are aggravating desertification and degradation of forests such as urbanization, droughts, exploitation of natural resources and climate change. The study aims at estimating and assessing the degradation of forests in arid and semi-arid regions. This task however is complicated since the impact of the degradation will be in different forms such as loss of wood, soil erosion and lost recreational areas. Nevertheless the dynamic impact of the degradation is increasing the complexity of analysis since forest once lost is a reduction of value for all subsequent years. This study is considering the value of damages over time and it is using the concept of three environmental valuation methods to estimate the whole impact of the degradation: the habitat equivalency analysis (HEA), the productivity method and the benefit transfer method. The methods were applied to specific values of forests, depending on the best applicability, and the results combined to an overall value loss. The costs are calculated based on the year 2014 with two time horizons: 30 and 100 years. To apply the valuation approach, Jordan as an arid and semi-arid country is chosen. The result shows that the annual costs of environmental degradation of Jordanian forest areas equal about 0.14% of GDP in 2013, proving the enormous value lost to forest degradation or deforestation. The valuation approach can be transferred to other arid or semi-arid areas and stimulate forest conservation activities to prevent further degradation and to save the forest ecosystem services for the future.     

Inter-cellular spike coincidences in visual detection tasks

Synchronized spike activity is discussed as a possible representational code for object integration and as a neuronal basis of attention, perception and awareness. As a byproduct of experiments in which monkeys were trained to detect simple figures composed of single Gabor patches in a noisy background of similar elements, we found in special cases increased spike synchrony above chance level specifically related to figure detection. The long latency of this effect is difficult to interpret. It may be a sign of the cognitive state of an animal when it perceives the figure.     

The capacity of duckweed to treat wastewater: ecological considerations for a sound design

Duckweed species are promising macrophytes for use in sustainable wastewater treatment due to their rapid growth, ease of harvest, and feed potential as a protein source. This paper reviews growth rates of different duckweed species on wastewater and ammonia toxicity to duckweed and summarizes insights into the mechanism of organic matter and nutrient removal. Results were gained from laboratory experiments in small, shallow, duckweed-covered semicontinuous batch systems. Growth rates on different types of wastewater vary considerably among different species. Ammonia is toxic for duckweed in both the ionized and un-ionized forms. Duckweed, however, can be used to treat wastewater containing very high total ammonia concentrations as long as certain pH levels are not exceeded. The degradation of organic material is enhanced by duckweed through both additional oxygen supply and additional surface for bacterial growth. The duckweed mat with attached bacteria and algae is, independent of the loading rates, responsible for three-quarters of the total nitrogen (N) and phosphorus (P) loss in very shallow systems. Based on our results we suggest that full-scale pilot plants with duckweed should be shallower than the range encountered in the literature. A harvesting schedule that allows doubling times of 2 to 3.5 d, maintenance of a full coverage, and plug flow conditions are recommended.     

HYDROLOGIC STAGE PERIODICITY OF THE MISSISSIPPI RIVER BEFORE AND AFTER SYSTEMATIC CHANNEL MODIFICATIONS1

ABSTRACT: Periodic flood disturbance is a well known controlling factor of in channel and floodplain ecosystem function. However, channel manipulations during the last century have potentially altered hydrologic fluctuations, and thus ecosystem function. We examined temporal river stage hydrology, through autocorrelation analysis, at seven gauges along the Mississippi River to quantify flow periodicity and effects of systematic channel modifications on flow periodicity. Intraannual variation follows a strong one‐year cycle of six months higher flow and six months lower flow for the entire Mississippi River drainage, with precipitation as a driving force. Interannual hydrologic variation differs between the upper and lower river segments. A clear quasi‐biennial oscillation pattern was evident throughout the lower river section. The effect of channel alterations was a decreased magnitude of differences between lower and higher flows. The upper section, however, suggests a 12‐to 14‐year periodicity prior to alterations and a decreased duration of lower flow years following systematic modifications. Interannual variograms clearly depict very different temporal hydrology between the upper Mississippi River and the lower Mississippi River, suggesting the simple transfer of knowledge from one segment to the other oversimplifies the complexity of a large river system.     

On the significance of adult play: what does social play tell us about adult horse welfare?

Play remains a mystery and adult play even more so. More typical of young stages in healthy individuals, it occurs rarely at adult stages but then more often in captive/domestic animals, which can imply spatial, social and/or feeding deprivations or restrictions that are challenging to welfare, than in animals living in natural conditions. Here, we tested the hypothesis that adult play may reflect altered welfare states and chronic stress in horses, in which, as in several species, play rarely occurs at adult stages in natural conditions. We observed the behaviour (in particular, social play) of riding school horses during occasional outings in a paddock and measured several stress indicators when these horses were in their individual home boxes. Our results revealed that (1) the number of horses and rates of adult play appeared very high compared to field report data and (2) most stress indicators measured differed between ‘players’ and ‘non-players’, revealing that most ‘playful’ animals were suffering from more chronic stress than ‘non-playful’ horses. Frequency of play behaviour correlated with a score of chronic stress. This first discovery of a relationship between adult play and altered welfare opens new lines of research that certainly deserves comparative studies in a variety of species.     

Comparative evaluation of four suspended particulate matter (SPM) sampling devices and their use for monitoring SPM quality

Environmental Science and Pollution Research - Representative sampling of suspended particulate matter is fundamental for assessing river sediment quality, including the distribution and...     

Influence of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on ammonia-oxidizing bacteria and archaea in rhizosphere and bulk soil

In agricultural plant production nitrification inhibitors like 3,4-dimethylpyrazole phosphate (DMPP) are used to retard the microbial nitrification process of fertilized ammonium to enhance the nitrogen supply for cultivated crops and to reduce nitrogen losses from the production system. Besides the well-known ammonia-oxidizing bacteria (AOB) it is known for a few years that also ammonia-oxidizing archaea (AOA) are able to perform the first step in nitrification, hence being also a target for a nitrification inhibitor. However, so far no information are available concerning the effectiveness of DMPP and its extent towards AOB and AOA, neither in bulk soil nor in the root-rhizosphere complex. We investigated in a field experiment performed according to agricultural practice the effect of DMPP on the abundance of AOB and AOA two, four and eight weeks after fertilization. We observed impaired abundances of AOB but not of AOA in both soil compartments that were still visible eight weeks after application, possibly indicating a reduced effectiveness of the nitrification inhibitor in our study.     

Air parcel model simulations of a convective cloud: Bacteria acting as immersion ice nuclei

The effects of bacteria acting as immersion ice nuclei were investigated in numerical sensitivity studies and compared to the efforts of other ice nuclei such as mineral dust and soot particles. An adiabatic air parcel model was employed simulating convective situations with different initial aerosol particle distributions. The maximum fractions of active ice nuclei were based on field measurements of the proportioning of atmospheric aerosol particle types in continental and marine air masses. Recent field measurements of bacteria concentrations in cloud water and in snow samples were used. From the concentrations in bulk samples the concentration in mean sized cloud droplets was estimated. Immersion freezing was described based on laboratory measurements to constrain the freezing fraction versus temperature. The results indicated that the effects of diminutive amounts of bacteria on ice formation in convective clouds, while being significantly less than the effects of mineral dust particles, might be comparable to the expected effects of soot particles acting as ice nuclei. It can be predicted that bacterial ice nuclei would have to be enriched by at least 10⁴ times reported concentrations in cloud water in order to equate to the impact of mineral dust ice nuclei present in 20–25% of all cloud droplets.