Characteristics and potential values of bio-oil, syngas and biochar derived from Salsola collina Pall. in a fixed bed slow pyrolysis system.[Pubmed: 27595703]

Salsola collina Pall. as a typical euhalophyte was slowly pyrolyzed at 300°C, 500°C and 700°C in a fixed-bed system. The physiochemical properties of syngas, bio-oil and biochar were assayed to understand the impact of pyrolysis temperature on these parameters and then to evaluate their potential values. The results showed that syngas yield (26.07-46.37%) increased with pyrolysis temperature, while biochar yield (47.54-26.83%) decreased. Bio-oil yield (26-30%) was hardly affected by pyrolysis temperature. Both syngas and bio-oil had poor values as direct fuel. The euhalophyte-derived biochar had higher aromaticity (H/C 0.16-0.85, O/C 0.06-0.26), higher cation exchange capacity (198.82-435.74cmolkg(-1)), and higher K(+) (59.35-80.42gkg(-1)) and Na(+) (37.56-53.26gkg(-1)) compared with glycophyte-derived biochars. Our findings imply that halophyte biochar may be more suitable to use as a soil conditioner, which is worthy of further study.

[Spectral reflectance characteristics of dominant plant species at different eco-restoring stages in the semi-arid grassland].[Pubmed: 25752064]

The objective of the research is to apply hyperspectral technique into eco-restoring monitoring. Through the ASD Fields HH portable field spectrometer, the hyperspectral data of dominant plant species in vegetation at different eco-restoring stages in semi-arid grassland in Helin County, Inner Mongolia were collected. The original spectrum reflected data were pretreated by wavelet threshold denoising through ViewSpecPro software before analysis. Using the first derivative spectra between 660 and 800 nm, and the methods of detrended canonical correspondence analysis (DCCA) by Canoco 4. 5 software, the canopy hyperspectral datum of 6 dominant plant species was calculated. The results indicated that the dominant plant species at early succession stage were Setaria viridis and Caragana microphylia, at 5 years eco-restoring stage they were Salsola collina and Caragana microphylia and at late succession stage they were Pinus sylvestnis var. mongolica and Salsola collina, same as field survey. The graph of DCCA indicated that the influential bands of dominant species canopy at early eco-succession stage were short bands, with a large variation among species, the influential bands at 5 years eco-restoring stage were near infrared bands between 1 000 and 1 050 nm, and that at late stage were near infrared bands of 1 040-1 075 nm. The DCCA also showed obviously differences in canopy spectrum among 6 dominant species, and obviously differences among 3 eco-restoring stages.

Phenotypic plasticity of early and late successional forbs in response to shifts in resources.[Pubmed: 23185600]

We compared the phenotypic plasticity of two early successional forbs of nutrient-poor mobile dunes (Agriophyllum squarrosum and Corispermum macrocarpum) and two later successional forbs (weeds) of stabilized, higher nutrient dunes and cropland (Chenopodium acuminatum and Salsola collina) to variations in environmental factors. A controlled (including soil nutrients, water, and population density) greenhouse experiment was conducted in Horqin sandy land, China. Late successional species had high plasticity in growth response to nutrients and water or high performance in high soil nutrients and water, reflecting their higher nutrient habitat. In contrast, the early successional species have low plasticity, reflecting their adaptation to resource-poor early successional soil. Late successional species did not always have higher reproductive effort than early successional species. Plants did not have a uniform strategy of increasing reproductive effort with any environmental stressors. Reproductive effort increased with increasing water availability and decreasing nutrient levels, while density had no effect. Patterns of plasticity traits for late successional species exhibited a complex of Master-of-some and Jack-of-all-trades. Late successional species had higher performance or higher plasticity than early successional species.

Increasing nitrogen deposition enhances post-drought recovery of grassland productivity in the Mongolian steppe.[Pubmed: 22584584]

Arid regions are prone to drought because annual rainfall accumulation depends on a few rainfall events. Natural plant communities are damaged by drought, but atmospheric nitrogen (N) deposition may enhance the recovery of plant productivity after drought. Here, we investigated the effect of increasing N deposition on post-drought recovery of grassland productivity in the Mongolian steppe, and we examined the influence of grazing in this recovery. We added different amounts of N to a Mongolian grassland during two sequential drought years (2006 and 2007) and the subsequent 3 years of normal rainfall (2008-2010) under grazed and nongrazed conditions. Aboveground biomass and number of shoots were surveyed annually for each species. Nitrogen addition increased grassland productivity after drought irrespective of the grazing regime. The increase in grassland productivity was associated with an increase in the size of an annual, Salsola collina, under grazed conditions, and with an increase in shoot emergence of a perennial, Artemisia adamsii, under nongrazed conditions. The addition of low N content simulating N deposition around the study area by the year 2050 did not significantly increase grassland productivity. Our results suggest that increasing N deposition can enhance grassland recovery after a drought even in arid environments, such as the Mongolian steppe. This enhancement may be accompanied by a loss of grassland quality caused by an increase in the unpalatable species A. adamsii and largely depends on future human activities and the consequent deposition of N in Mongolia.

[Studies on the chemical constituents of Salsola collina].[Pubmed: 21823480]

To study the chemical constituents of Salsola collina.

[Dynamics of plant community species diversity in the process of ecological rehabilitation in north Shaanxi loess area].[Pubmed: 19459383]

Based on the vegetation survey on 18 sampling plots in Wuqi County of Shaanxi Province, and by using the methods of substituting space series for time series and of contrastive analysis, the dynamics of plant community species diversity in the process of ecological rehabilitation in the County was analyzed from the aspects of succession time, rehabilitation mode, and slope direction. The results showed that in the 25 years natural succession series, the natural restoration community on previous cropland experienced the sequence of Salsola collina, Artemisia scoparia, Lespedeza davurica, Artemisia sacrorum, and Bothriochloa ischcemum, with the dominant species tended to be changed from annual to perennial and from low-class to high-class. The variations of species number, Margalef index, Simpson index, Shannon-Wiener index, and Pielou index in the succession process could all be described by a quadratic function y = at2 + bt + c, suggesting that after the outside pressure removed, the degraded ecosystem in loess area could naturally restore to an advanced and steady state, but the restoration rate would be very slow. With the same site factors and restoration periods, the Margalef index, Shannon-Wiener index and Pielou index of herb layer decreased in the order of naturally restoring on previous cropland (I) > converting cropland to grassland (II) > converting cropland to forestland (III) > afforestation on barren hills (IV), while Simpson index changed in adverse. Comparing with natural restoration, the community types of herb layer in II and III were at the more advanced stage of natural succession series though the species diversity index was lower, indicating that artificial planting would accelerate the succession process. In the same period of rehabilitation, the Margalef index, Shannon-Wiener index and Pielou index of natural restoration community were obviously higher on shady slope than on sunny slope, and the community type was at the more advanced stage of natural succession series, suggesting that the basic ecological rehabilitation condition on sunny slope was worse, and the succession rate was slower.

A new alkaloid from Salsola collina.[Pubmed: 17702398]

Salsola collina is widely distributed in droughty and semi-droughty area, which is used as a kind of folk remedy in traditional Chinese medicine for treatment of hypertension. The study is on the chemical constituents of this herb from its aerial parts to obtain its active constituents. Dried and crushed aerial parts of this herb were extracted three times with 95% EtOH at reflux. The ethanol extracts were combined and concentrated under reduced pressure at 70 degrees C to yield residue, which was suspended in water and successively partitioned with light petroleum, chloroform and n-butanol. The chloroform and n-butanol fractions were treated by various chromatographic techniques, such as silica gel, C18 reversed-phase silica gel and macroporous resin column chromatography. Compounds were elucidated by their physicochemical properties and spectroscopic analysis. In the course of our study on searching biological active components from this herb, a new alkaloid together with three known alkaloids were isolated and identified as N-transferuloyl-3-methyldopamine (1), 3-[4-(beta-D-glucopyranosyloxy)-3-methoxyphenyl]-N-[2-(4-hydroxyl-3-methoxyphenyl) ethyl]-2-propenamide (2), salsoline A (3), salsoline B (4). Compound 4 is a new compound and named as salsoline B, while compound 2 was obtained in Salsola collina for the first time.

[Studies on chemical constituents of Salsola collina].[Pubmed: 17511147]

To study the chemical constituents of Salsola collina.

Natural recovery of steppe vegetation on vehicle tracks in central Mongolia.[Pubmed: 16595879]

Steppe desertification due to vehicle travel is a severe environmental issue in Mongolia. We studied natural vegetation recovery on abandoned vehicle tracks in the central Mongolia steppe through vegetation surveys and stable isotopic techniques. The following issues were addressed: (i) invasion of pioneering plant species, (ii) alteration of soil surface features, and (iii) contribution of revegetated plants to soil organic matter (SOM). The pioneering plant species that firstly invaded the abandoned tracks are those that could germinate, root and survive in the compacted track surface. Salsola collina is one of these candidate plants. Due to revegetation, soil surface hardness was reduced. With the improvement of surface microenvironmental conditions, other plants began to colonize and establish; con-comitantly species richness and species diversity increased. Carbon isotope ratios of SOM at the top surface layer indicated that C4 -derived carbon contributed more to SOM in the early phase of recovery and decreased with further recovery.

[Effects of different cutting system on main typical steppe populations in Inner Mongolia].[Pubmed: 16515182]

Twelve main typical steppe populations in Inner Mongolia were selected to investigate the effects of different cutting system on their aboveground standing biomass. The results showed that the test populations could be categorized into 3 groups, i.e., (1) group with decreasing biomass, which included Leynzus chinensis, Agropyron michnoi, Caragana microphylla and Carex korshinskyi, with L. chinensis and C. microphylla as the representatives. The average aboveground standing biomass of L . chinensis was decreased by 63.37%, 64.96%, 45.64% and 34.18% after 2 cuttings a year, 1 cutting a year, 1 year cutting and 1 year resting, and 2 years cutting and 1 year resting, while that of C. microphylla decreased by 81.79%, 63.33%, 40.29% and 26.30%, respectively, compared with the control; (2) group with increasing biomass, which included Koeleria cristata, Artemisia scoparia, A . frigida, and Salsola collina, and K. cristata and A . frigida were the representatives. The biomass of K. cristata was increased by 94.84%, 287.79%, 132.86% and 211.74%, while that of A. frigida was increased by 193.02%, 210.47%, 154.65% and 160.47%, respectively. The biomass increase of K. cristata and A. frigida was derived from their population changes, while that of A. scoparia and S. collina was come from the decrease of community densities and the more suitable conditions for seed germination; (3) group with fluctuated biomass, which included Stipa grandis, Achnatherum sibiricum, Artemisia commutata and Serratula centauroides, and the change patterns of their biomass were between those of the former 2 groups.