Search

A good knowledge of species diversity is essential for urban forest planning and management. In this study, we analyzed species diversity of urban forests in China using data synthesized through a systematic review. Our analysis showed that 3740 taxa of woody plants at species level and below have been reported in urban forests in 257 cities. Merging to the species level, there were 2640 species, including 1671 trees, 743 shrubs, and 226 lianas. Salix babylonica L. was the most widely distributed urban tree species in China. Overall, native species accounted for 76.02% of the observed species while the rest were exotic species. Inside cities, parks contained more species than other types of land use. Among cities, composition similarity of urban forests decreased as spatial distances among them increased. Besides, there was a latitudinal pattern in compositional similarity of urban forests in China. The relatively low ratio of the number of woody plant species in urban forests to these naturally distributed in China indicates that there is plenty of room for increasing species diversity of urban forests in China. However, cautions must be taken to avoid increasing compositional similarity of urban forests in China at the same time. [ABSTRACT FROM AUTHOR]

In this article, Salix babylonica leaves powder (SBLP) has been used for the removal methylene blue (MB) from aqueous solutions by adsorption process. The surface of SBLP analyzed by scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR). The effects of changing parameters such as adsorbent dosage, contact time, pH, temperature, and initial dye concentration on methylene blue adsorption were investigated. Three isotherm equations, Langmuir, Freundlich, and Temkin, have been tested in order to describe the equilibrium characteristics of adsorption. The experimental data fitted well by Langmuir isotherm, with maximum adsorption capacity 60.97 mg/g. The experimental data were fitted using pseudo-first-order and pseudo- second-order and intraparticle diffusion models. The experimental results were fitted better with pseudo-second-order model compared to the other two models. The amount of thermodynamic parameters such as Gibbs free energy (∆ G ° ), change in enthalpy of adsorption (∆ H ° ), and change in entropy (∆ S ° ) were calculated and this parameter showed that MB adsorption on SBLP is spontaneous and exothermic in nature. The result of experimental shows that SBLP is suitable low-cost adsorbent for removal of methylene blue from aqueous solutions. [ABSTRACT FROM AUTHOR]

Abstract: Sixteen growing Katahdin×Pelibuey lambs (24±0.3kg body weight) were used to study the effects of oral administration of extracts of Salix babylonica (SB) and Leucaena leucocephala (LL) leaves on ruminal pH, total and individual volatile fatty acids (VFA) and NH3-N concentrations, as well as ruminal protozoal counts, urinary purine derivatives (PD) excretion and estimated microbial protein synthesis. Lambs were fed a total mixed ration (TMR) containing 219 and 141gkg−1 of CP and NDF, respectively. Four treatments (4lambs/treatment) were Control (no extract added), SB (SB extract at 30mld−1), LL (LL extract at 30mld−1) and SBLL (mixture of SB at 15mld−1+LL at 15mld−1). Extracts were administered orally to each lamb before the morning meal daily. Measurements were on days 22 (P1), 43 (P2) and 63 (P3) of the experiment. Ruminal pH increased (P=0.014) with SBLL extract and decreased with SB. The ratio of acetate to propionate was higher (P=0.042) with SBLL compared to the control. Ruminal NH3-N concentration was not affected by extract administration (P=0.309) or experimental period (P=0.087). Protozoal counts were not affected (P=0.489) by extract addition but decreased (P<0.001) in P3 compared with P1 and P2. Uric acid concentration increased (P<0.001) with individual extracts of SB and LL compared with the control or SBLL. Excretion of other purine derivatives (allantoin, xanthine, and hypoxanthine), creatinine and microbial protein synthesis were not changed (P>0.05) by extracts administration. Overall, oral administration of S. babylonica and L. leucocephala extracts, or their 1:1 mixture, to lambs for 63d had only minor effects on ruminal fermentation, urinary purine derivative excretion and microbial protein synthesis. [Copyright &y& Elsevier]

Abstract: This study was conducted to determine if adaptation of lambs to ingestion of tree leaf extracts of Salix babylonica and Leucaena leucocephala can modify in vitro gas production of Celtis ehrenbergiana, Ficus trigonata, Fraxinus excelsior and Prunus domestica. Samples of leaves were collected in triplicate (i.e., three individual samples of each tree leaf). Rumen inoculum was collected from 8 growing lambs fed a total mixed ration ad libitum (control; RC). Incubations were repeated with the rumen fluid collected from another 8 growing lambs of the same breed fed the same ration, but fed a daily dose of 30ml/d of S. babylonica and L. leucocephala extracts in a 1:1 (v:v) mixture (treatment; RX). Leaf samples were incubated with each rumen fluid (i.e., RC and RX inoculums) in 3 runs on different weeks. Data of each of the three runs within sample replicate were averaged and used as the mean value of each individual sample within tree species for statistical analysis in a 4 (tree species)×2 (rumen inoculum) factorial design. In vitro gas production was recorded at 2, 4, 6, 8, 10, 12, 24, 48 and 72h of incubation. After 72h, the incubation was stopped and supernatant pH was determined, and then filtered to determine apparent degraded substrate (ADS). Fermentation parameters, such as the 72h partitioning factor (PF72), 24h gas yield (GY24), in vitro organic matter digestibility (IVOMD), metabolizable energy (ME), short chain fatty acids concentration (SCFA), and microbial protein production (MP) were estimated. The crude protein content of the leaves ranged from 147 (F. trigonata) to 241 (C. ehrenbergiana) g/kg dry matter. The lowest fiber fraction values was in P. domestica, while F. excelsior had the highest, and C. ehrenbergiana and F. trigonata were intermediate. Secondary metabolites (i.e., total phenolics, saponins, aqueous fraction) were lowest in P. domestica and highest in F. trigonata. Accumulated gas production was highest (P<0.05) in F. excelsior during the first 24h of incubation. All fermentation parameters (i.e., ADS, SCFA, GY24, PF72, IVOMD, ME, MP) varied (P<0.01) among tree leaves. The ADS, SCFA and MP were highest (P<0.01) in F. excelsior, lowest (P<0.01) in F. trigonata, and intermediate in P. domestica and C. ehrenbergiana. Incubation of tree leaves with RX inoculum did not affect gas production in the first 6h, but it was lower (P<0.05) at 24–72h, except for F. trigonata. C. ehrenbergiana had the highest (P<0.05) potential gas production, but rate of gas production and the discrete lag time did not differ among leaves. As incubation of tree leaves with RX inoculum lowered (P<0.05) all fermentation parameters, oral administrated extracts of S. babylonica and L. leucocephala did not seem to adapt the rumen microbial population to better utilize these tree leaves. [Copyright &y& Elsevier]

Abstract: Thirty two Katahdin×Pelibuey crossbreed male lambs 3–4 months of age and 24±0.3kg body weight (BW) were used to study effects of administration of extracts rich in secondary compounds from Salix babylonica (SB) and Leucaena leucocephala (LL) on feed intake, nutrient digestibility and growth. After 2 weeks of adaptation consuming a total mixed ration (TMR; 219 and 141g/kg of crude protein (CP) and neutral detergent fibre (NDFom), respectively), lambs were weighed and distributed by BW into 4 pens of 8 lambs/pen in a completely randomized design with: Control group TMR; SB group TMR (as Control plus S. babylonica extract at 30ml/d); LL group TMR (as Control plus L. leucocephala extract at 30ml/d); SBLL group TMR (as Control plus 30ml/d of S. babylonica and L. leucocephala extracts in a (1:1, v:v) mixture) for a 63 days experiment. Weekly stock volumes (2l each) of the individual extracts as well as their 1:1 mixture were prepared for daily administration. Extracts were orally administered before the 08:00h feeding to each lamb. Feed intake was recorded daily and BW was recorded at d 22 (P1), d 43 (P2) and d 63 (P3) of the experiment. Each experimental period ended with a digestibility measurement. Average daily gain (ADG), metabolizable protein (MP) intake and metabolizable energy (ME) intake were calculated. Plant secondary metabolites of total phenolics, saponins and the aqueous fraction were 50% lower in SB versus LL extracts. An extract×experimental period interaction occurred for intake of all nutrients (SB>LL=Control>SBLL, P<0.05). Intake of DM, OM, CP and ADFom were lowest in P3 than other periods, whereas the highest nutrients intake were in P2 and P1 (P<0.05). Individual extracts improved (SB>LL, P=0.05) the digestible DM, OM, EE and CP more than their 1:1 mixture compared with control or SBLL. Digestible DM was improved (P=0.03) by 5 and 3% with SB and LL extracts respectively, compared to control, whereas digestible CP was improved (P=0.005) by 7 and 5%, respectively, compared to control. Digestible ADFom was drastically lower in P1 and increased steadily in periods P2 and P3 (P<0.001). Feed intake was not affected by extract addition although it was reduced from P1 and P2 to P3. Relative to control, addition of extracts increased (P=0.024) ADG while the other performance parameters (i.e., MP intake, ME intake) had a tendency (P=0.05) to improve with extract addition. ADG was improved by about 22 and 21% with SB and LL extracts respectively, while their mixture (i.e., SBLL) was 2% compared to control (i.e., SB=LL>Control=SBLL, P=0.024). MP and ME intakes were decreased (P<0.0001) from P1 and P2 to P3. Results show that daily administration of individual extracts of S. babylonica and L. leucocephala improved lamb performance by 22 and 21%, but that a mixture of both had a much lower benefit. [Copyright &y& Elsevier]

Abstract: Fusarium wilt disease is one of the major plant diseases that affect tomato production. The effects of neem (Azadirachta indica) and willow (Salix babylonica) aqueous extracts on fusarium wilt disease in tomato seedlings were investigated. Four weeks old tomato seedlings were treated with 10% of either neem and willow aqueous extracts and then infected with Fusarium oxysporum after 4days of treatment. The results showed that the percentage of disease incidence was increased in non treated tomato seedlings in time dependent manner and reached the maximum level (65%) after 6weeks of infection. Treatments of tomato plants with neem and willow aqueous extracts reduced the percentage of disease incidence to the level of 25.5% and 27.8% after 6weeks of infection respectively. The results show that infection of tomato seedling with Fusarium oxysporum led to many morphological and biochemical changes including, reducing the growth of tomato shoot and root, increasing the level of lipid peroxidation and marked increase in the activities of antioxidant defensive enzyme i.e. POX, CAT, and SOD. Treatment with neem and willow aqueous extracts significantly exhibited a growth promotion of tomato shoot and root in infected or non infected seedling. Moreover, application of neem and willow aqueous extracts with fusarium, significantly reduce the level of lipid peroxidation and induce high activities of antioxidant defensive enzymes after 3 and 7days of infection. Electrophoretic pattern of POX demonstrated that Fusarium oxysporum caused up regulation of several POX isoenzymes. It could be concluded that neem and willow aqueous extracts reduced the disease incidence of fusarium wilt in tomato seedlings by increasing the activities of antioxidant defensive enzymes and decreasing the level of lipid peroxidation [Copyright &y& Elsevier]

Abstract: Air samples in four seasons at one site and tree bark samples from four districts were determined to investigate seasonal variation and regional distribution of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) in Beijing, China. The total concentrations of PBDEs (∑PBDE) and HBCD (∑HBCD) were in the range of 57–470 and 20–1800pgm−3 in the atmosphere, respectively. The ∑PBDE and ∑HBCD concentrations were significantly influenced by the total suspended particulate matter in atmosphere. The total concentrations of PBDEs and HBCD in tree bark samples were in the range of 99–3700 and 26–3400ngg−1 lipid weight. It was found that regional distribution of PBDEs and HBCD was related to the function of each district. In addition, the study found that weeping willow bark was an ideal atmospheric PBDEs and HBCD passive sampler. Finally, atmospheric levels of BDE-209 and HBCD at tree bark sampling districts were estimated via applying an established bark/air partitioning model, which had been verified by the measured concentrations in tree bark and atmosphere in Beijing. [Copyright &y& Elsevier]

Abstract: As environmental legislation has become stricter in recent years, the issue of wastewater treatment in rural areas has become an increasing concern. Choice of the most suitable on-site purification systems is based on the key issues of affordability and appropriateness in Chinese rural areas. This paper describes an integrated household constructed wetland (IHCW) system planted with willow (Salix babylonica) to treat household domestic wastewater in rural villages in northern China. The precast frame structure of IHCW is strong and waterproof. It can be mass-produced and installed per a standard set of specifications. The IHCW has achieved high overall removal efficiencies for BOD5, TSS, NH4-N, and TP: 96.0%, 97.0%, 88.4% and 87.8%, respectively. A 0.4m biomass layer cover on the system provided significant system thermal insulation, maintaining high treatment performance in freezing winter conditions. The system is cost effective and does not need any operational energy inputs, demonstrating its feasibility for single-family use in developing countries. [Copyright &y& Elsevier]

Biotransformation and metabolic responses of plants to cyanide were investigated using pre-rooted plants of weeping willows (Salix babylonica L.) grown hydroponically in growth chambers and treated with potassium cyanide. Various physiological parameters of the plants were monitored to determine toxicity from exogenous cyanide exposure. Cyanide doses used in this study showed growth-promoting effects on plants, exhibiting higher measured values of transpiration rates, chlorophyll contents and soluble protein contents compared with the non-treated control plants. Superoxide dismutases (SOD), catalase (CAT) and peroxidase (POD) activities in leaves showed a slight change to cyanide application in most treatments. Of all selected parameters, soluble proteins of plants were the most sensitive indicator to cyanide application. Almost all applied cyanide was removed from the hydroponic solution in the presence of plants in all treatment groups. Small amounts of cyanide were detected in the plant tissues. Recovery of cyanide in different compartments of plants varied significantly, root being the dominant sink for cyanide accumulation. Mass balance studies showed that >97% of the applied cyanide was metabolized during transport through weeping willows and the metabolic rates of cyanide by plants were linearly increased with increasing of cyanide applied in the growth media. Results from this study indicated that neither visible toxic symptom nor metabolic lesion was observed for the plants after 192h of exposure, largely due to the well-established detoxification systems in willows. These findings suggest that cyanide has a beneficial role in plants and phytoremediation is a desirable solution of treating environmental sites contaminated with cyanide. [Copyright &y& Elsevier]

Linear alkylbenzene sulfonate (LAS) is the most commonly used anionic surfactant in laundry detergents and cleaning agents. LAS compounds are found in surface waters and soils. The short-term acute toxicity of LAS to weeping willows (Salix babylonica L.) was investigated. Willow cuttings were grown in hydroponic solution spiked with LAS at 24.0±1°C for 192h. The normalized relative transpiration of plants was used to determine toxicity. Severe reduction of the transpiration was only found for high doses of LAS (⩾240mgl−1). Chlorophyll contents in leaves of treated plants varied with the dose of LAS, but there was no significant linear correlation. The activities of the enzymes superoxide dismutases (SOD), catalase (CAT), and peroxidase (POD) were quantified at the end of experiments. At higher concentrations of LAS (⩾240mgl−1), the activities of SOD and CAT were decreased. The correlation between the dose of LAS and the POD activity in leaf cells was the highest of all enzyme assays (R 2 =0.5). EC50 values for a 50% inhibition of the transpiration of the trees were estimated to 374mgl−1 (72h) and 166mgl−1 (192h). Results from this experiment indicated that phytotoxic effects of LAS on willow trees are not expected for normal environmental conditions. [Copyright &y& Elsevier]

Abstract: The response of cyanide metabolism rates of two woody plants to changes in temperature is investigated. Detached leaves (1.0g fresh weight) from weeping willow (Salix babylonica L.) and Chinese elder (Sambucus chinensis Lindl.) were kept in glass vessels with 100ml of aqueous solution spiked with potassium cyanide for a maximum of 28h. Ten different temperatures were used ranging from 11°C to 32°C. The disappearance of aqueous cyanide was analyzed spectrophotometrically. The cyanide removal rate of Chinese elder was higher than that of weeping willow at all temperatures. The highest cyanide removal rate for Chinese elder was found at 30°C with a value of 12.6mgCNkg−1 h−1, whereas the highest value of the weeping willow was 9.72mgCNkg−1 h−1 at 32°C. The temperature coefficient values, Q 10, which are the ratio of removal rates at a 10 degree difference, were determined for Chinese elder and weeping willow to 1.84 and 2.09, respectively, indicating that the cyanide removal rate of weeping willow was much more susceptible to changes in temperature than that of the Chinese elder. In conclusion, changes in temperature have a substantial influence on the removal rate of cyanide by plants. [Copyright &y& Elsevier]

Discusses the metabolism in mature leaves of Ginkgo biloba and Salix babylonica species. Detailed information on metabolism in each species; Major site of cytokinin biosynthesis in the plant; Details on the study and its findings.

Presents studies which deal with the cytokinins in root nodules of Salix babylonica and in bark tissue of Ginkgo biloba. Materials and methods used to conduct the study; Analysis of cytokinins; Cytokinin content of Salix babylonica bark tissue; Other results from the study; Discussion of results.

Examines the changes which occured in foliar cytokinins of Salix babylonica and Ginko biloba prior to and during leaf senescence. Trend towards an increase in the proportion of cytokinin O-glucosides during leaf maturity; Changes in endogneous cytokinin of leaves in Ginkgo biloba with foliar senescence.

Attempts to proof that cytokinin glucosides are exported from senescing leaves prior to abscission. Application of [3H](OG)DHZ to the leaves of `Salix babylonica; Percentage of the radioactivity which moved basipetally; Possibility of the occurrence of the export of cytokinin glucosides.