Chemical state analysis of sulfur and phosphorus in biological samples by X-ray fluorescence

Double-crystal high-resolution X-ray fluorescence spectroscopy was applied to the chemical state analysis of sulfur and phosphorus in biological samples of leaves and bones. Both S²⁻ and S⁶⁺ states are present in all leaves. In plants infected with the mosaic virus, the abundance of S²⁻ state was found to be less than normal. Furthermore, the total sulfur content of leaves with the mosaic virus was less than that in normal leaves. From these results we have concluded that the mosaic virus is related to the decrease in cysteine sulfur (S²⁻), which is an essential component in amino acids. Most of the phosphorus in leaves and bones was found to be in P⁵⁺ state. A small amount of P³⁺ state, however, was also detected.     

Temperature-dependent lateral and transverse distribution of the epidermal growth factor receptor in A431 plasma membranes

Summary To elucidate further the structure and molecular dynamics of the epidermal growth factor receptor, temperature-dependent aggregation and extracellular protrusion of the epidermal growth factor receptor in isolated plasma membranes from A431 cells were examined by fluorescence energy-transfer techniques. Epidermal growth factor was labeled at the amino terminus with either fluorescein isothiocyanate or tetramethylrhodamine isothiocyanate. A radionuclide receptor displacement assay demonstrated the bioactivity of these derivatives. Aggregation of the epidermal growth factor receptor was measured by determining the increase in fluorescence energy transfer between receptorbound fluorescein and tetramethylrhodamine-labeled epidermal growth factor. Energy transfer between receptor-bound fluorescent derivatives was reversibly greater at 37 than 4°C, indicating temperature-dependent aggregation of the receptor. The extracellular protrusion of the epidermal growth factor receptor was calculated from the magnitude of energy transfer between receptorbound fluorescein labeled epidermal growth factor and 5-(N-dodecanoylamino)-eosin partitioned into the lipid membrane at 4 and 37°C. No significant change in the distance of closest approach between the N-terminus of epidermal growth factor and the plasma membrane was observed at 4°C (69±2 Å) and 37°C (67±2 Å). Thus, the extracellular protrusion of the occupied epidermal growth factor receptor did not change detectably upon receptor aggregation.     

X-ray fibre diffraction study of conformational changes in hyaluronate induced in the presence of sodium,potassium and calcium cations

Hyaluronate purified from all cations by ion exchange chromatography was introduced to the cations sodium, potassium and calcium in a controlled way. The conformations formed in the presence of these ions were studied as a function of ionic strength, hydrogen ion activity, humidity and temperature using X-ray fibre diffraction. In sodium hyaluronate above pH 4.0 a contracted helix is found which approximates to a four-fold helix with an axial rise per disaccharide of 0.84 nm. There is no requirement for water molecules in the unit cell as the Na⁺ can be coordinate by the hyaluronate chains alone. On crystallizing hyaluronate below pH 4.0 an extended 2-fold helix with an axial rise per disaccharide of 0.98 nm is formed. In the presence of potassium above pH 4.0 a conformation similar, but not identical, to that of sodium was found where the helix backbone is again four-fold with an axial rise per disaccharide h=0.90 nm. To maintain the coordination of the potassium ion, four water molecule/disaccharide are required and on removal of these the conformation is destabilized going to a new helix where n = 4 and h = 0.97 nm. Below pH 4.0 the conformation is a contracted 4-fold helix with h = 0.82 nm. In this structure two antiparallel chains intertwine to form a double helix. The packing of the double helical units is stabilized by water molecules, the unit cell requiring 8 water molecules/disaccharide. Formation of the calcium hyaluronate complex above pH 3.5 yields a three-fold helix with h = 0.95 nm. The requirement for water in the unit cell to maintain full crystallinity is high, at 9 water molecules/disaccharide; however, on removal of this water, though the crystallinity is disrupted, the conformation remains constant. The acid form of calcium-hyaluronate yields an equivalent conformation to that of sodium under the same condition, i.e. a helix with n = 2, h = 0.98 nm. The presence of small quantities of calcium in what are otherwise potassium or sodium solutions of hyaluronate yield the 3-fold conformation for hyaluronate. Thus calcium has an important role to play in deciding the dominating conformation present in hyaluronate. The variety of conformations yielded by the different cations indicates a subtle interaction between hyaluronate and its environment, in which the balance between the cations will control to some degree the interactions between hyaluronate chains and thus affect the mechanical properties of the matrix which they form. The conformations of individual chains are all stabilized in varying degrees by intra-chain hydrogen bonds.     

Impact of changes in natural ultraviolet radiation on pigment composition, physiological and morphological characteristics of the Antarctic moss, Grimmia antarctici

The impact of ambient ultraviolet (UV)‐B radiation on the endemic bryophyte, Grimmia antarctici, was studied over 14 months in East Antarctica. Over recent decades, Antarctic plants have been exposed to the largest relative increase in UV‐B exposure as a result of ozone depletion. We investigated the effect of reduced UV and visible radiation on the pigment concentrations, surface reflectance and physiological and morphological parameters of this moss. Plexiglass screens were used to provide both reduced UV levels (77%) and a 50% decrease in total radiation. The screen combinations were used to separate UV photoprotective from visible photoprotective strategies, because these bryophytes are growing in relatively high light environments compared with many mosses. G. antarctici was affected negatively by ambient levels of UV radiation. Chlorophyll content was significantly lower in plants grown under near‐ambient UV, while the relative proportions of photoprotective carotenoids, especially β‐carotene and zeaxanthin, increased. However, no evidence for the accumulation of UV‐B‐absorbing pigments in response to UV radiation was observed. Although photosynthetic rates were not affected, there was evidence of UV effects on morphology. Plants that were shaded showed fewer treatment responses and these were similar to the natural variation observed between moss growing on exposed microtopographical ridges and in more sheltered valleys within the turf. Given that other Antarctic bryophytes possess UV‐B‐absorbing pigments which should offer better protection under ambient UV‐B radiation, these findings suggest that G. antarctici may be disadvantaged in some settings under a climate with continuing high levels of springtime UV‐B radiation.     

Early detection of premalignant changes in cell cultures using light-induced fluorescence spectroscopy

Light-induced fluorescence (LIF) spectroscopy has demonstrated ability as a novel, noninvasive and sensitive technology for early detection of cancer. The goal of the present study is to examine the potential of this spectroscopic method for early detection and characterization of premalignant changes. As a model we used both cell lines and primary cells, which were transformed to malignant by retrovirus. Fluorescence measurements and morphological observations of the infected cells were performed at various postinfection times. Our results showed gradual attenuation of fluorescence intensities due to cancer progression which corresponds to aromatic amino acids and nicotinamide adenine dinucleotide (NADH) molecules. In order to obtain grading and supervised classifications of the spectral premalignant changes we used approaches of linear discriminant analysis. The classifications based on Mahalanobis distances allowed us to demonstrate that the accuracy of identification of premalignant stages varied between 83.1% and 96.4%. In summary, we conclude that LIF in tandem with proper statistical tools may be a promising technique for early detection of malignant progression.     

The role of trace elements in the pathogenesis and progress of pilocarpine-induced epileptic seizures

X-ray fluorescence microscopy was applied for topographic and quantitative elemental analysis within the areas of the rat brain that undergo neurodegenerative changes in consequence of pilocarpine-induced seizures. Significant changes in levels of selected elements were observed in epileptic animals. They included an increased tissue content of Ca in the CA1 and CA3 regions of the hippocampus and in the cerebral cortex. The opposite relation was observed for the Cu level in the dentate gyrus and for Zn in the CA3 region of the hippocampus and in the dentate gyrus.     

Aluminium Fluoride induced changes in chlorophyll a fluorescence,antioxidants and psb A gene expression of Brassica juncea cultivars

In present study, the effects of combined Aluminium and Fluoride (AlF) stress on chlorophyll a fluorescence, photosynthetic pigments, antioxidant system and psb A gene expression are first time reported in four Brassica juncea cultivars (CS-14, Pusa-Tarak, Bio-902 and Laxmi). Each cultivar was exposed to soil supplemented with AlF (0, 50?+?25, 100?+?50 and 150?+?75?mgkg^?1). Lowest decline in the chlorophyll content, saturating photosynthetically active photon flux density, maximum apparent electron transport rate and effective quantum yield (PSII) under AlF was observed in Pusa-Tarak followed by CS-14, Bio-902 and Laxmi. The improved performance of the cultivar Pusa-Tarak under AlF stress was accompanied by an increase in proline level and enzymes activity of catalase and ascorbate peroxidase. However, significant increase in superoxide dismutase activity was observed in cultivar Laxmi. We also observed that AlF inhibits psb A gene expression to a lesser extent in tolerant cultivar Pusa-Tarak in comparison to susceptible cultivar Laxmi.     

Regional changes in density of serotonin transporter in the brain of 5-HT1A and 5-HT1B knockout mice, and of serotonin innervation in the 5-HT1B knockout

5-HT1A knockout (KO) mice display an anxious-like phenotype, whereas 5-HT1B KOs are over-aggressive. To identify serotoninergic correlates of these altered behaviors, autoradiographic measurements of 5-HT1A and 5-HT1B serotonin (5-HT) receptors and transporter (5-HTT) were obtained using the radioligands [3H]8-OH-DPAT, [125I]cyanopindolol and [3H]citalopram, respectively. By comparison to wild-type, density of 5-HT1B receptors was unchanged throughout brain in 5-HT1A KOs, and that of 5-HT1A receptors in 5-HT1B KOs. In contrast, decreases in density of 5-HTT binding were measured in several brain regions of both genotypes. Moreover, 5-HTT binding density was significantly increased in the amygdalo-hippocampal nucleus and ventral hippocampus of the 5-HT1B KOs. Measurements of 5-HT axon length and number of axon varicosities by quantitative 5-HT immunocytochemistry revealed proportional increases in the density of 5-HT innervation in these two regions of 5-HT1B KOs, whereas none of the decreases in 5-HTT binding sites were associated with any such changes. Several conclusions could be drawn from these results: (i) 5-HT1B receptors do not adapt in 5-HT1A KOs, nor do 5-HT1A receptors in 5-HT1B KOs. (ii) 5-HTT is down-regulated in several brain regions of 5-HT1A and 5-HT1B KO mice. (iii) This down-regulation could contribute to the anxious-like phenotype of the 5-HT1A KOs, by reducing 5-HT clearance in several territories of 5-HT innervation. (iv) The 5-HT hyperinnervation in the amygdalo-hippocampal nucleus and ventral hippocampus of 5-HT1B KOs could play a role in their increased aggressiveness, and might also explain their better performance in some cognitive tests. (v) These increases in density of 5-HT innervation provide the first evidence for a negative control of 5-HT neuron growth mediated by 5-HT1B receptors.     

Comparison of light induced and cell cycle dependent changes in the photosynthetic apparatus: A fluorescence induction study on the green alga Scenedesmus obliquus

Changes in the photosynthetic apparatus occurring during the synchronous cell cycle of the green alga Scenedesmus obliquus are compared to the adaptational response induced by light intensity variations. To investigate and compare these two phenomena, we analyze the polyphasic rise of the chlorophyll fluorescence yield exhibited by plants and cyanobacteria when exposed to high intensity actinic light. Four fluorescence parameters are calculated which are closely related to Photosystem II (PS II) structure and function: ABS/RC, the antenna size of PS II; _PO, the quantum yield for reduction of the primary PS II quinone acceptor; q_PQ, related to the size of the plastoquinone pool; q_Emax, the capacity for pH dependent non-photochemical quenching. The capacity for non-photochemical quenching changes in response to light intensity variations, but it is not affected by the developmental changes occurring during the cell cycle. In contras t, for ABS/RC, _PO and q_PQ, we observe light induced as well as cell cycle dependent variations. We discuss the relations of the four fluorescence parameters to the molecular organization of the photosynthetic apparatus and its cell cycle and light dependent changes.     

Phase-sensitive fluorescence spectroscopy: A new method to resolve fluorescence lifetimes or emission spectra of components in a mixture of fluorophores

A novel phase fluorometric method is described which permits direct recording of individual emission spectra from a mixture of two flourescent compounds. Additionally, the lifetimes of each component may be determined by examination of the phase-sensitive fluorescence spectra. The method utilizes phase-sensitive detection of the sinusoidally modulated emission from a phase fluorometer. Resolution of the individual emission spectra in the mixture requires different fluorescence lifetimes for each components. Determination of the individual lifetime requires knowledge of the steady-state emission spectra of the components. Use of low-frequency (≈ 10 Hz) cross-correlated signals eliminates the need for high-frequency frequency (≈10⁶ Hz) phase-sensitive detection. A mixture of 2-p-toluidinyl-6-naphthalenesulfonic acid (TNS) and 6-propionyl-2-(dimethylamino)naphthalene (PRODAN) was used to demonstrate the possibility of phase resolution of fluorophore mixture and to confirm theoretical predictions. A mixture of dibenzo[a,h]anthracene and dibenzo[c,g]carbazole was used to demonstrate that phase resolution is possible for spectra which overlap strongly and which are highly structured. In addition, the possibility of using phase-sensitive emission spectra for the resolution of excited-state reactions was demonstrated with anthracene and its diethylaniline exciplex. From a sample whose steady-state emission displayed both components we directly recorded the emission spectrum of anthracene monomer and the exciplex. For all these samples the dependence of the individual intensities on the phase angle of the detector agreed precisely with that expected on the basis of the individual fluorescence lifetimes. The detector phase angles chosen for suppression of each component in the mixture also agreed with the measured lifetimes. Thus, phase-sensitive fluorescence spectra can reveal individual spectral distributions or lifetimes. This method will be useful in the analysis fluorescence emissions which frequently occur from proteins, membranes and other biological samples.     

Polymorphism of the Serotonin Receptor Type 2A (5-HTR2A) Gene and Verbal Fluency in Normalcy and in Schizophrenia

To study the effect of the serotonergic brain system on verbal fluency (i.e., the ability to rapidly extract necessary words from the internal vocabulary), the T102C polymorphism of the serotonin receptor type 2A (5-HTR2A) gene was tested for association with verbal fluency in 108 patients with schizophrenia or disorders of the schizophrenic spectrum and 97 mentally healthy individuals. A significant association was observed only in male schizophrenics (n = 67), with homozygotes A2A2 having lower verbal fluency. The results do not support the association between the 5-HTR2A polymorphism and verbal fluency in normalcy, and agree with the assumed contribution of genotype A2A2 to the severity of schizophrenia.     

Protein expression changes in the Sprague Dawley rat liver proteome following administration of peroxisome proliferator activated receptor alpha and gamma ligands

Peroxisome proliferator activated receptors (PPARs) are members of the nuclear receptor superfamily and are intimately involved in lipid metabolism and energy homeostasis. Activation of these receptors in rodents can lead to hepatomegaly and ultimately hepatic carcinogenesis although the mechanisms by which these processes occur are poorly understood. To further our understanding of these processes and to discriminate between different PPAR mediated signalling pathways, a proteomic approach has been undertaken to identify changes in protein expression patterns in Sprague Dawley rat liver following dosing with a PPARalpha agonist (Wyeth 14643), a PPARgamma agonist (Troglitazone) and a compound with mixed PPARalpha/gamma agonist activity (SB-219994). Using one-and-two-dimensional electrophoresis of tissue lysates a diverse range of protein abundance changes was observed in these tissues. Whilst a number of these proteins have PPAR response elements (PPREs) in their respective promoters, another group was detected whose expression has been documented to be sensitive to peroxisome proliferator administration. Most notably within these groups, proteins involved in lipid catabolism displayed increased expression following drug administration. A further subset of proteins, with less obvious biological implications, also showed altered expression patterns. Where available, sequences upstream of the coding regions of genes not previously known to have PPREs were searched with positional consensus matrices for the presence of PPREs in an attempt to validate these changes. Using such an approach putative PPARgamma and PPARdelta response elements were discovered upstream of the tubulin beta coding region. There was limited overlap in observed protein abundance changes between the three groups, and where this was the case (cytosolic epoxide hydrolase, peroxisomal bifunctional enzyme, hydroxymethyl glutaryl CoA, synthase, long chain acyl-CoA thioesterase), expression of these proteins had previously been shown to be under the control of PPAR activity.     

Distinctive and Synergistic Signaling of Human Adenosine A2a and Dopamine D2L Receptors in CHO Cells

Adenosine A_2a receptor (A_2aR) colocalizes with dopamine D₂ receptor (D₂R) in the basal ganglia and modulates D₂R-mediated dopaminergic activities. A_2aR and D₂R couple to stimulatory and inhibitory G proteins, respectively. Their opposing roles in regulating neuronal activities, such as locomotion and alcohol consumption, are mediated by their opposite actions on adenylate cyclase, which often serves as “co-incidence detector” of various activators. On the other hand, the neural actions of A_2aR and D₂R are also, at least partially, independent of each other, as indicated by studies using D₂R and A_2aR knock-out mice. Here we co-expressed human A_2aR and human D_2LR in CHO cells and examined their signaling characteristics. Human A_2aR desensitized rapidly upon agonist stimulation. A_2aR activity (80%) was diminished after 2 hr of pretreatment with its agonist CGS21680. In contrast, human D_2LR activity was sustained even after 2 hr and 18 hr pretreatment with its agonist quinpirole. Long-term (18 hr) stimulation of human D_2LR also increased basal cAMP levels in CHO cells, whereas long-term (18 hr) activation of human A_2aR did not affect basal cAMP levels. Furthermore, long-term (18 hr) activation of D_2LR dramatically sensitized A_2aR-induced stimulation of adenylate cyclase in a pertussis toxin-sensitive way. Forskolin-induced cAMP accumulation was significantly increased after short-term (2 hr) human D_2LR stimulation and further elevated after long-term (18 hr) D_2LR activation. However, neither short-term (2 hr) nor long-term (18 hr) stimulation of A_2aR affected the inhibitory effects of D_2LR on adenylate cyclase. Co-stimulation of A_2aR and D_2LR could not induce desensitization or sensitization of D_2LR either. In summary, signaling t hrough A_2aR and D_2LR is distinctive and synergistic, supporting their unique and yet integrative roles in regulating neuronal functions when both receptors are present.     

Iron levels in the human brain: A post-mortem study of anatomical region differences and age-related changes

The link between brain iron homeostasis and neurodegenerative disease has been the subject of extensive research. There is increasing evidence of iron accumulation during ageing, and altered iron levels in some specific brain regions in neurodegenerative disease patients have been reported.Using graphite furnace atomic absorption spectrometry after microwave-assisted acid digestion of the samples, iron levels were determined in 14 different areas of the human brain [frontal cortex, superior and middle temporal, caudate nucleus, putamen, globus pallidus, cingulated gyrus, hippocampus, inferior parietal lobule, visual cortex of the occipital lobe, midbrain, pons (locus coeruleus), medulla and cerebellum (dentate nucleus)] of n = 42 adult individuals (71 ± 12 years old, range: 53–101 years old) with no known history or evidence of neurodegenerative, neurological or psychiatric disorders.It was found that the iron distribution in the adult human brain is quite heterogeneous. The highest levels were found in the putamen (mean ± SD, range: 855 ± 295 μg/g, 304–1628 μg/g) and globus pallidus (739 ± 390 μg/g, 225–1870 μg/g), and the lowest levels were observed in the pons (98 ± 43 μg/g, 11–253 μg/g) and medulla (56 ± 25 μg/g, 13–115 μg/g).Globally, iron levels proved to be age-related. The positive correlation between iron levels and age was most significant in the basal ganglia (caudate nucleus, putamen and globus pallidus).Compared with the age-matched control group, altered iron levels were observed in specific brain areas of one Parkinson's disease patient (the basal ganglia) and two Alzheimer's disease patients (the hippocampus).     

A fluctuation analysis study of the development of amiloride-sensitive Na+ transport in the skin of larval bullfrogs (Rana catesbeiana)

In the presence of the Na⁺-channel blocker amiloride, the short-circuit current across the skins of bullfrog tadpoles in metamorphic stages XIX–XXIV was subjected to fluctuation analysis. The resulting power spectra contained a Lorentzian component of which the plateau value ($\text{S}{}_0$) decreased while the corner frequency ($\text{f}{}_{\mathrm{<mtext>c</mtext>}}$) increased as the mucosal amiloride concentration was increased from 0.5 to 24 μM. From the linear relationship between the $\text{f}{}_{\mathrm{<mtext>c</mtext>}}$ values and the amiloride concentrations it was possible to determine the binding ($\text{k′}{}_{01}$) and unbinding ($\text{k}{}_{10}$) constants for amiloride to its receptor on the Na⁺ channel. With these parameters as well as short-circuit current and $\text{S}{}_0$ values, the current through the individual Na⁺ channels ($\text{i}$) was calculated (average 0.58 pA). It did not increase significantly during late metamorphosis. The density of Na⁺ channels ($\text{M}$) in the apical membrane, on the other hand, increased significantly. It would appear that the increase in short-circuit current which occurs at this time is due primarily to an increase in amiloride-blockable Na⁺ channels. Unexpectedly, a Lorentzian component could be fitted to power spectra in amiloride-treated skins (stages XIX–XXI) which showed no amiloride-sensitive short-circuit current. Moreover, the typical increase in $\text{f}{}_{\mathrm{<mtext>c</mtext>}}$ with the amiloride concentration did not occur in these animals.     

A novel index for analysing the response of a microbial culture to changes in the environmental variables during cultivation

AIMS: To analyse the sensitivity of a microbial culture to variations in the cultivation conditions by using the motile intensity of the cells. METHODS AND RESULTS: Batch cultures of Bacillus thuringiensis were used to study the sensitivity of the cells to pulse changes in pH, temperature and oxygen supply. A droplet of the culture sample was visualized under an optical microscope and the image of the moving cells was captured with a computer controlled display camera attached to the microscope. Motile intensity was computed directly using an image analysis programme. The results showed that the different phases of cell growth exhibited different motile intensities. The motile intensity changed remarkably at the high level of the motile intensity, when the environmental variables are changed. CONCLUSIONS: The product formation was considerably reduced when a disturbance was applied at the high magnitude of motile intensity. SIGNIFICANCE AND IMPACT OF STUDY: Monitoring the motile intensity by image analysis is simple and makes it an attractive method for assessing the effect of environmental variables on the growth and product formation of microbial cultures.     

A palynological study of environmental changes and their implication for prehistoric settlement in the Ilan Plain, northeastern Taiwan

Pollen records from two sediment cores taken from Ilan Plain, northeastern Taiwan provide new insights into the environmental and cultural history of the last 4200 years. The record indicates a relatively warm climate at around 4200 cal b.p. The environmental conditions would have been suitable for people whose settlements and activities were mainly in the littoral zone during this period. However, at ca. 3800 cal b.p., elements tolerant of brackish water dominated the vegetation, indicating that the environment was influenced by marine incursion. The remarkable increase in wetland flora suggests the presence of widespread marshlands thereafter. It is quite conceivable that settlement movement from the fluvial plain to hills between 3800 and 2400 cal b.p. can be correlated with the environmental changes in lowlands. A conspicuous gap in the archaeological sequence between 2400 and 1300 cal b.p. corresponds chronologically with a period of heavy rainfall or frequent typhoons as indicated by the aggradational episode in the Lanyang drainage basin as well as the flourishing of Alnus forests. The persistence of frequent landslides and climate deterioration would have had a dramatic impact on ancient humans and led to abandonment of the settlements. By 1300 cal b.p. a lowland flora is widespread indicating a shift from a marsh to a terrestrial environment in response to a well-developed fluvial plain. Decrease of landslides and the amelioration in climate could have advantages to human activities again. However, both the pollen and archaeological records indicate that intensive colonisation had a profound effect upon the vegetation within the Ilan region about 400 years ago.     

Linear analysis applied to the comparative study of the I-D-P phase of chlorophyll fluorescence as induced by actinic PS-II light,PS-I light and changes in CO2-concentration

The investigation of the kinetics of chlorophyll-fluorescence under continuous background light enables the application of linearizing conditions. This approach, which provides a quantitative evaluation by means of curve-fitting routines, is applied to the investigation of the linear kinetics of the I-D-P phase. Using changes in PS II-light, PS I-light and in CO₂-concentration as input signals showed that a pool at the acceptor side of PS I, in addition to the plastoquinone pool, plays an essential role in the generation of the dip. The occurrence of the dip is related to the sign of the faster one of the two components related to the I-D and the D-P phase. This sign can be inverted by the ratio of PS I and PS II light. However, model calculations show that the change of this sign does not allow a decision which one of the two components is related to which one of the two pools. The dependence of the sign of the faster component on light conditions can generate different types of I-D-P transitions, namely nearly monophasic increases, sigmoid responses or dips. As these phenomena are already created by the linear responses, non-linear effects or additional loops between PS II and PS I are not required for the explanation of the basic features.Abbreviations ETC electron transfer chain - F fluorescence - PQ plastoquinone pool - PS Photosystem - X pool at the acceptor side of PS I     

Assessment of land use changes through an indicator-based approach: A case study from the Lamone river basin in Northern Italy

This study has been performed in order to evaluate the land use changes and related environmental impacts which occurred in recent decades in the Lamone river basin (Northern Italian Apennines). Using the DPSIR indicator-based approach, agricultural land use changes and conversions occurred within the periods 1976–1994 and 1994–2003, have been associated with the shortage of water in the river and the modification of the landscape structure. Results show that Lamone river basin in 1976 was mainly dominated by forest (27.4%) and cropland (32.3%) and through the entire period the valley presented a strong persistence of land uses and the main conversions detected are afforestation and agricultural intensification. The hydrological balance analysis results indicate that the agricultural intensification process produced a water deficit in summer periods equal to 0.89 mln m³ in 2003. The landscape of the Lamone valley became more homogeneous, showing a decrease in diversity (Shannon Diversity Index values decreased from 1.81 to 1.58) and the riparian corridor became more human-dominated (Human Habitat values increased from 0.61 to 0.77). An integrated assessment of possible management options has been conducted, using the MULINO-DSS software as a support. Thirteen different management scenarios have been produced in order to solve the water balance issue and to enhance the riparian corridor. Attributing equal weight to the environmental, social and economical criteria, the best solution corresponds to the sole creation of artificial basins and the actual situation is placed at position 8 (out of 13).