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2015 Vol.32(11)

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2015, 9(11): 0-.
[Abstract](1027) [PDF 3780KB](454)
Orginal Article
Temporal and spatial variation of net primary productivity (NPP) and its responses with climatic changes in the Xilingol grassland from 2000 to 2010
Hai-jiang LIU, Si-yang YIN, Cong SUN, Fu-li PENG, Peng ZHOU
2015, 9(11): 1709-1720. doi: 10.11829/j.issn.1001-0629.2015-0371
[Abstract](974) [FullText HTML] (131) [PDF 1869KB](527)
Using MODIS MOD17A3 Net Primary Productivity (NPP) data and meteorological data, we analyzed the temporal and spatial variation of NPP, inter-annual changes of climatic factors and the correlative relationship between NPP and climatic factors in Xilingol grassland from 2000 to 2010. The NPP of the Xilingol grassland varied from 0 to 0.5 kg C·m-2 which decreased from east to west. From 2000 to 2010, the NPP fluctuated annual that increased in generaland evenly distributed. The variations of climatic factors in typical and desert grassland were similar. The cumulative average temperature, average relative humility and cumulative sunshine duration in April to August had a downward trend, while the average wind speed had an increasing trend. The cumulative precipitation hadan increasing trend in desert grassland, but had a slight decreasing trend in typical grassland. For most climatic factors, they had more dramatic fluctuations in typical grassland than in desert grassland. For the two types of grassland in the study area, the grassland NPP has very significantly negative correlation (P<0.001) with cumulative average temperature and average daily minimum temperature in April to August, and had slight negative correlation with cumulative sunshine duration and average wind speed, while had strong positive correlation (P<0.001) with cumulative precipitation and average relative humility. In conclusion, the typical grassland had stronger response ability to the changes of climatic factors than the desert grassland.
Simulation of vegetation net primary productivity and evapotranspiration based on LPJ model in Central Asia
Jian-cai ZHANG, Li ZHANG, Yi ZHENG, Xiang-jun TIAN, Yu ZHOU
2015, 9(11): 1721-1729. doi: 10.11829/j.issn.1001-0629.2015-0103
[Abstract](1220) [FullText HTML] (164) [PDF 1465KB](470)
Central Asia is one of the most sensitive regions to climate changes in the world and the ecological environment is very fragile. The two main vegetation types, grasslands and croplands, are very easily influenced by water shortages and humans activities. Study on changes of net primary productivity (NPP) and evapotranspiration(ET), and their relationship with climate are important in Central Asia. In the present study, the spatio-temporal patterns and changes of NPP and ET in Central Asia (1982-2012) were analyzed based on LPJ model. The results indicated that the spatial distributions of NPP and ET were very consistent. The high-values were mainly located in forests, the mixed area of grass-forest and croplands, whereas the low-values were mainly concentrated in sparse vegetated area around the desert and grasslands of central Kazakhstan. The annual NPP and ET showed a fluctuated increasing trend. Annual NPP varied from 469.59 Tg C·a-1 to 1 130.26 Tg C·a-1 with mean of 737.24 Tg C·a-1(185.57 g C·m-2·a-1). Annual ET varied from 695.53 km3·a-1 to 1 047.69 km3·a-1 with mean of 850.46 km3·a-1 (214.07 mm·a-1). The main climate factor influencing the variations of NPP and ET was precipitation in Central Asia, while temperature played less important role in the region. The vegetation productivity of Kyrgyzstan and Tajikistan increased at a faster rate, yet Turkmenistan indicated a decline trend. Kazakhstan, Uzbekistan and Xinjiang’s vegetation productivitywere relatively stable.
The accuracy of grassland vegetation biomass estimated model based on multi-source remote sensing data ——As a case of experimental area in Sangke grassland in Xiahe County
Bao-ping MENG, Si-yu CHEN, Xia CUI, Qi-sheng FENG, Tian-gang LIANG
2015, 9(11): 1730-1739. doi: 10.11829/j.issn.1001-0629.2015-0015
[Abstract](797) [FullText HTML] (57) [PDF 956KB](537)
Based on the remote sensing data of MODIS, Landsat-8 OLI and HJ-1A/1B CCD combined with ground observation data during 2013 and 2014 in the experimental area of Xiahe County, Gansu Province, the alpine grassland biomass inversion models were established and evaluated, and the best inversion models based on different remote sensing vegetation indexes were selected. Meanwhile, the spatial and temporal variations of grassland biomass in experimental area from 2000 to 2013 were also analyzed. The results showed that the best grassland biomass inversion model was logarithmic function of Landsat-8 OLI NDVI data(y=727.54lnx1+495.23, R2=0.772,RMSE=31.333 kg DM·hm-2). With spatial resolution of 30 m and 250 m, estimated biomass based on MODIS NDVI, MODIS EVI, HJ-1A/1B CCD NDVI and Landsat-8 OLI NDVI, were all higher than ground observation biomass. The estimated biomass based on logarithmic function of Landsat-8 OLI NDVI was the most close to observation biomass. The total biomass in the experimental area had great changes from 2000 to 2013. As a whole, the total biomass of grassland has a significant increasing trend (R2 = 0.590 7, P<0.001) from 2000 to 2013, and the average increasing rate reached to 50.57 kg DM ·hm-2·a-1.
The spatiotemporal characteristics of NDVI, precipitation and RUE during 2000-2012 in Xinjiang
Chun-e LI, Qiu-rong LIU, Li-jun ZHANG
2015, 9(11): 1740-1747. doi: 10.11829/j.issn.1001-0629.2015-0355
[Abstract](923) [FullText HTML] (72) [PDF 1569KB](457)
In the present study, the spatial distribution characteristics and the interannual variation of NDVI, precipitation and RUE from June to September during 2000-2012 in Xinjiang were analyzed. The results showed that the spatial distribution characteristics of monthly mean precipitation and monthly mean NDVI decreased from northwest to southeast, and the annual precipitation and annual NDVI increased in north Xinjiang, decreased in south Xinjiang although the annual precipitation changed more obvious. The spatial distribution comparison characteristics of monthly mean precipitation and monthly mean RUE was not obvious and the variation of annual precipitation and annual RUE was opposite. In different land use types, there was significantly positive correlation between precipitation and NDVI (r>0.3, P<0.05) which showed that precipitation conditions had significant influence on the vegetation spatial distribution. There was significantly negative correlation between precipitation and RUE(r<-0.22, P<0.05), which showed the inhibition effect of excessive precipitation on vegetation photosynthesis.
Effects of livestock exclosure and grazing on carbon sequestration in grassland ecosystem
Jing-ru ZOU, Xin-quan ZHAO
2015, 9(11): 1748-1756. doi: 10.11829/j.issn.1001-0629.2015-0096
[Abstract](1073) [FullText HTML] (127) [PDF 489KB](533)
Carbon sequestration in the grassland ecosystems has important effects on the global carbon stocks. Grazing as one of the most widely land usage methods affects carbon sequestration in the grassland.However, unreasonable and over-grazing can lead to grassland degradation which has negative effects on carbon stocks in the grassland. Livestock enclosure and grazing affect carbon sequestration in the grassland by altering the vegetation productions and soil carbon stocks. This review indicated that livestock exclosure and grazing had positive or negative effects on the vegetation production which were affected by some other factors and their interaction, such as aboveground litter, vegetation structure, climate conditions, and so on. The effects of grazing on vegetation production were also related to the grazing intensity. Livestock exclosure and grazing had positive or negative effects on soil carbon stocks by affecting many processes in the soil carbon cycling. In summary, the effects of livestock exclosure and grazing on carbon sequestration in grassland were complicated. In order to make the scientific decision on grassland managements,the estimations of carbon stocks and researches on the related mechanisms are necessary in the further study.
Dynamic simulation of soil organic carbon pool of wolfberry forest in the secondary saline-alkali land in the arid regions in Jingtai, Gansu ——Take Jingtai electricity-powered irrigation zone as a case study
Tao SUN, Quan-lin MA, Zhi-qing JIA, Yin-ke LI, Yao-lin WANG, Xiao-juan ZHANG, Jun-mei MA
2015, 9(11): 1757-1766. doi: 10.11829/j.issn.1001-0629.2015-0101
[Abstract](916) [FullText HTML] (73) [PDF 640KB](306)
The dynamics variations of soil carbon pool were simulated using CENTURY modelbased on the soil layer of 0-20 cm in wolfberry forest growing in the typical secondary saline-alkali land in Hongyue Village of Jingtai County, Gansu. The simulation results showed that there were significant changes in total soil organic matter after planting wolfberry in the reclaimed secondary saline-alkali land which increased firstly and then decreased like the inverted “V.” After the reclamation of secondary saline-alkali land, the soil organic carbon of wolfberry forest rapidly increased during seedling growth stage(1st~4th year old) as “carbon sink stage”, then, it declined gradually during mature stage(8th~12th years old) which reached the level of before land reclamation. Carbon pool activity, carbon pool index(CPI) and carbon pool management index (CPMI) also increased firstly and then decreased, which suggested that soil quality firstly improved through planting wolfberry and then gradually declined with wolfberry growth. These variations closely related with the current farmland management and crops cultivation like irrigation, fertilizer. The wolfberry forest possibly converts to weak carbon emission source in the next 20 to 30 years without change of the current farmland conditions. Therefore, it is very important to employ different measures like changing farmland management, increasing organic fertilizer input, adopting scientific irrigation equipments, and replacing the old seedlings, and so on, to improve the quality of wolfberry forest soil, and increase soil carbon reservation, and reduce the greenhouse effects.
Physical and chemical properties of soil in alfalfa field for different cultivated years
Kun XU, Shi-zhong LI
2015, 9(11): 1767-1773. doi: 10.11829/j.issn.1001-0629.2015-0140
[Abstract](1078) [FullText HTML] (83) [PDF 465KB](345)
The present study evaluated soil physical and chemical properties in alfalfa field for different cultivated years in semiarid region. The results showed that with the cultivated period increasing, the soil bulk density changed irregularly with relative high values. Soil organic matter increased with the alfalfa’s growing years, while decreased significantly withthe increased depth of soil (P<0.01). Soil organic matter in five years alfalfa field had the highest increase whereas it was the lowest in the eight years alfalfa field. There was characteristic of soil organic matter surface accumulation for each experiment site and there were accumulation only in range of cultivated period. Soil total nitrogen content firstly increased and then decreased with the cultivated period increasing, but decreased with the soil depth increased. Soil total nitrogen content reached the peak in four years alfalfa field and reached the minimum in eight years alfalfa field. And soil total nitrogen content mainly accumulated in 0-40 cm of soil layer which suggested that soil total nitrogen significantly accumulated in the surface soils. Soil nitrate nitrogen content firstly increased and then decreased with the cultivated period increasing, but decreased with the soil depth increased. Soil nitrate nitrogen content accumulated in the surface soil of 0-5 cm. There was significant correlation between soil nitrate nitrogen content and the growing time of alfalf (P<0.05). Soil ammonium nitrogen did not changed a lot in the soil profile which had no significant correlation with the growing time of alfalfa. The management measures to improve the best cultivation and utilization year in cultivated alfalfa field need be further studied.
Community characteristics of vegetation in earthquake disturbed zone in Longnan, Gansu
Rui XUE, Ji-qiang ZHANG, San-ying WANG, Chun-shan CHAI, Jing-hui WANG, Ya-ping ZHAO
2015, 9(11): 1774-1780. doi: 10.11829/j.issn.1001-0629.2015-0058
[Abstract](905) [FullText HTML] (93) [PDF 483KB](307)
The seismic disturbance causes great damages to the local ecological environment, which leads to the changes of species composition and structure of vegetation community. The present paper investigated and analyzed the species composition and structure of vegetation community after earthquake disturbance in Qingshui Gully,Wudu District, Longnan City of Gansu Province from August to September of 2013 using the methods of belt transect combined with altitudinal gradient. The results showed that there were 34 plant species which belong to 30 genera,16 families in the study area although the main vegetations were Gramineae and Compositae plants. There was obvious vertical structure of vegetation community which could be divided into three layers. The perennial herbs were dominant which had the highest species number in the community. The shrub and vine followed and no arbor was observed. The Shannon-Wiener index (H') and Pielou evenness index (E) decreased in the following order: middle slope>lower slope>upper slope, and Simpson dominance index (D) decreased in the following order: upper slope>lower slope>middle slope.
Alien invasive species in Inner Mongolia and their influence on the grassland
Wen-tan TIAN, Yang LIU, Shu-yan WANG, Bing HAN
2015, 9(11): 1781-1788. doi: 10.11829/j.issn.1001-0629.2015-0117
[Abstract](1609) [FullText HTML] (338) [PDF 609KB](373)
Biological invasion is seriously threatening the biodiversity and ecological security of Inner Mongolia grassland. At present, the attentions were only paid to the introduction of alien species in Inner Mongolia region and even the national, but the lacks of management resulted in alien species release into the environment which might bring a potential environmental disaster. Based on literature review and database of alien invasive species in China, the present paper classified the alien invasive species distributed and summarized the effects of alien invasive species to grassland in Inner Mongolia. The corresponding control measures were proposed to reduce the alien species invasion. According to statistics, two alien invasive plants Galinsoga parviflora and Cenchrus calyculatus has shown a tendency to spread, and other species require further investigation.
The clonal growth of Zoysia japonica in response to the levels and orders of habitat resource gradient
Su-wen LAI, De-zhi LI, Hui-juan CHEN, Song GENG, Qing-qing CHEN, Xiao-tao YUN, Zhi-hua FAN, Yi OUYANG, Yao-yao HUANG, Ming-zu WANG
2015, 9(11): 1789-1800. doi: 10.11829/j.issn.1001-0629.2015-0112
[Abstract](832) [FullText HTML] (78) [PDF 713KB](431)
The clonal growth characteristics of Zoysia japonica in response to the levels and orders of habitat resource gradient were studied in the current experiment. The treatments consisted of high, low nutrient level gradients, and a whole range nutrient level gradient; every gradient consisted of a series of micro-habitats whose nutrient level increased or decreased, respectively. The results showed that the total biomass of Z. japonica clones changed with the gradient in the following order: high nutrient level gradient>low nutrient level gradient>whole range nutrient level gradient, and in every nutrient level gradient. The total biomass of Z. japonica clone was higher at decreasing order habitat than that at increasing order habitat, which suggested that both increasing the nutrient level in habitat and matching the nutrient supply in a micro-habitat with the growth requirement of each ramet could significantly improve the clonal growth of Z. japonica. The ratios of root/shoot of Z. japonica changed with the gradient in the following order: low nutrient level gradient>whole range nutrient level gradient>high nutrient level gradient, which suggested that the ramets of Z. japonica tended to be independent, and plastically responded to each micro-habitat and less affected by the neighbor ramets within the clone. In every gradient and habitat with various nutrient level and order, the growth of ramet A was superior to ramets B. The biomass allocation in the stolon was the largest in the whole range nutrient level gradient habitat whose total nutrient was at moderate level. The response of clonal growth of Z. japonica to the levels and orders of habitat resource gradient reflected the adaptation of its morphological plasticity.
The seed ecological mechanism of Xanthium strumarium invasion
Bo QU, Zhi-feng XUN, Yu-feng XU
2015, 9(11): 1801-1807. doi: 10.11829/j.issn.1001-0629.2015-0354
[Abstract](1340) [FullText HTML] (329) [PDF 920KB](313)
Exotic plants Xanthium strumarium in Northeast China has become one of the most serious invasive plants. In order to determine whether it can hybridize with native plants X. sibiricum. Acomparison of invasive plants X. strumarium, native plants X. sibiricumandthe reciprocal crossing fruits has been studied and the differences between fruit and germination characteristics have been discussed. The results showed that the front view area, perimeter, length and width, fruits weight, germination rate and speed of the reciprocal crossing (X. strumarium×X. sibiricum) and the inbred X. strumarium fruits were significantly higher than those of the reciprocal crossing (X. sibiricum×X. strumarium) and the inbred X. sibiricum (P<0.05). The perimeter, length and length of thorns of the reciprocal crossing fruits of X. strumarium(Xst♀×Xsi♂)were significantly longer than those of inbred X. strumarium fruits (P<0.05). Both the area, width, fruits weight, germination rate difference between these two fruits were not significant. The width and germination rate of reciprocal crossing fruits of X. sibiricum (Xsi♀×Xst♂) were significantly different with those of inbred X. sibiricum fruit (P<0.05). The width of the reciprocal crossing fruits of X. sibiricum (Xsi♀×Xst♂)was significantly higher than that of inbred X. sibiricum fruit whereas the germination rate was opposite. Therefore, the difference of fruit morphological characteristics between these two plants and their hybrid was significantly different. The reciprocal crossing fruits of X. strumarium(Xst♀×Xsi♂)was significantly higher than that of the inbred X. strumarium. The difference between the reciprocal crossing seeds of X. sibiricum (Xsi♀×Xst♂) and the inbred X. sibiricum seeds was not significant. The results suggested hybrid improve X. strumarium quality which may occupy space and resources more earlier than X. strumarium and X. sibiricum to increase the chance to invase.
Effects of drought and cold stress on seeds germination of Thymus vulgaris
Bo ZHAO, Xiu-yun YANG, Xiang-qun SHEN
2015, 9(11): 1808-1814. doi: 10.11829/j.issn.1001-0629.2015-0259
[Abstract](916) [FullText HTML] (44) [PDF 527KB](352)
In order to understand the optimal conditions for germination and seedling growth of import thyme seeds——Thymus vulgaris, the effects of PEG-simulated drought stress and low temperature on seed germination and seedling growth were measured. The analysis of two-way ANOVA showed that temperature, drought and their interaction significantly affected (P<0.05) the seed germination and seedling growth. The treatments with the temperature ranged from 8 ℃ to 24 ℃ and PEG-6000 ranged from 0 to 10% were optimal for seeds germination. The treatment with the temperature at 10 ℃ to 12 ℃ had the highest germination rate of 79.3%, which had significant difference from the other treatments (P<0.05). The treatments with 15% PEG-6000 could significantly inhibit (P<0.05) seed germination. Under the treatments with 30% PEG-6000, seeds only could germinate at 22 ℃ to 24 ℃. The root and shoot length under treatments with the temperature at 22 ℃ to 24 ℃ were significantly higher than the other treatments. Seeds and seedling growth had different response to PEG-simulated drought stress and cold.
Effects of drought and low temperature on seed germination of four mint species
Rui-fen REN, Xiu-yun YANG, Da-fang YIN, Fang GUO
2015, 9(11): 1815-1822. doi: 10.11829/j.issn.1001-0629.2015-0183
[Abstract](1049) [FullText HTML] (96) [PDF 585KB](341)
In the present study, the effects of drought simulating by PEG-6000 and low temperature on seed germination and seedling growth of four mint species were evaluated. The results showed that drought and low temperature had significant impacts (P<0.05) on the germination and seedling growth of four mint species seeds. The treatments with 30% PEG-6000 and 8~10 ℃ low temperature seriously restrained the seed germination and growth. Mentha citrata seeds showed stronger resistance to drought. The germination percentage of these four mint species seeds were the highest with the 22~24 ℃ treatment. There were differences for the growth of stem, root and leaves. The radicale and leaves of M. citrata grew well under 12~14 ℃. Interaction of drought and low temperature also had significant effect on the germination and growth of four species of mint seeds (P<0.001).
Effects of slope aspect on apparent traits and chlorophyll content of three cool season turf species
Xiao-lin ZENG, Da-wei WANG, Jin-ping LIU, Si-si WANG, Xuan FAN
2015, 9(11): 1823-1831. doi: 10.11829/j.issn.1001-0629.2015-0087
[Abstract](866) [FullText HTML] (59) [PDF 515KB](401)
In order to analyze the effects of slope aspect on apparent traits and chlorophyll content of three cool season turf species, three cool season turf species, including Festuca arundinacea, Lolium perenne, Poa pratensis, were mix-sowed for slope protection in the semi-shady slope, shady slope and sunny slope and the density, height, coverage, leaf traits and chlorophyll content of each species were determined during the young turf period, mature turf period and one year after mature turf period. The results showed that slope aspect had significant effects (P<0.05) on the height, density, coverage of three species in all of the three periods and the effects increased with the turf growth. Slope aspect had very significant effects (P<0.01) on the turf community density during young turf period and total coverage and density of turf community during mature turf and one year after mature turf. The effects of slope aspects decreased in the following order: semi-shady slope>shady slope>sunny slope, and the effects on turf community decreased in the following order: mature turf >one year after mature turf>young turf. The slope aspect had significant effect (P<0.05) on leaf areas and root-shoot ratios of all three tested species, and had very significant effects (P<0.01) on root length and tiller number whereas the interactions of slope aspect and species only had significant effects on root length. Both slope aspects and the interaction of slope aspect and specieshad very significant effects (P<0.01) on contents of the Chl a, Chl b and Chl (a+b) for all three tested species, however, the slope aspects only had significant effect on Chl a/b (P<0.05) and the interaction of slope aspect and species had no effects on Chl a/b. The three tested species had different performance on these three slope aspects which showed that F. arundinacea performed well, but P. pratensis performed worse on three kinds of slope, L. perenne only performed well on the shady slope. Therefore, the optimal turf species and appropriate management should be selected based on the slope aspect and micro environment to improve ecological benefits and landscape effects.
Effects of submerged height on allelopathic inhibition of Carex cinerascens to Microcystis aeruginosa in Poyang Lake marshland
Lin LI, Feng CHEN, Rong-fang ZHAO
2015, 9(11): 1832-1837. doi: 10.11829/j.issn.1001-0629.2015-0077
[Abstract](859) [FullText HTML] (43) [PDF 522KB](286)
In the present study, the allelopathy inhibition of Carex cinerascens soaking culture to Microcystis aeruginosa were studied with batch culture in light incubator controlling light and temperature and outdoors with different submerge height. The results showed that C. cinerascens soaking liquid inhibited the growth of M. aeruginosa and the inhibitory ratios increased with submerge height increasing which increased from 64% to 82%. C. cinerascens mainly secreted allelochemical by root system and dead or damaged tissues. Cell diameter of M. aeruginosa decreased by 10% compared with that of control group which suggested that the cells pyknosis. Intracellular and extracellular polysaccharide content of M. aeruginosa were 1.6~1.8 and 1.7~2.0 pg·cell-1, respectively. These results suggested that M. aeruginosa resist the allelopathic inhibitionby polysaccharide accumulation to form extracellular rubber sheath and single cells assembled to form group. This study provided the basis data forusing ecological regulation water level to control water bloom.
Evaluation and selection of excellent lines after polycross of alfalfa
Hong WANG, Shang-li SHI
2015, 9(11): 1838-1846. doi: 10.11829/j.issn.1001-0629.2015-0026
[Abstract](789) [FullText HTML] (66) [PDF 527KB](334)
In the present study, the production performance and quality traits of 3 alfalfa cultivars (Gannong No.3, Gannong No.5 and Eureka) and their offspring after polycross were evaluated by two consecutive year sfield test. White flower 1# and Fast-growing 12# were the best lines with the hay yield of 16.45 and 14.02 t·ha-1, plant height of 100.40 and 102.37 cm, branch numbers of 26 and 27, growth rates of 1.61 and 1.70 cm per day, stem-leaf ratio of 0.98 and 0.96, crude protein of 23.15% and 21.25%, and relative feeding value of 154.72% and 145.23%, respectively. Fast-growing 11#, White flower 2# and Fast-growing 15# had higher plant height and better branching ability and Fast-growing 5# and White flower 3# had higher hay yield, smaller stem-leaf ratio and rich crude protein. The lines mentioned above were better which can be used for further alfalfa breeding after comprehensive evaluation.
Effects of salinity, alkalinity, temperature and their interactions on seed germination of Medicago falcata
Yi WU, Yu TIAN, Hong-xiang ZHANG, Jian YANG, Zhi-hong WU
2015, 9(11): 1847-1853. doi: 10.11829/j.issn.1001-0629.2015-0317
[Abstract](1008) [FullText HTML] (72) [PDF 519KB](347)
In the present study, the effects of salinity, alkalinity, temperature and their interactions on seed germination of Medicago falcata were evaluated by treated with two neutral salts (NaCl, Na2SO4), two alkaline salts(Na2CO3, NaHCO3), and three alternating temperature(10/20 ℃, 15/25 ℃ and 25/35 ℃). The results showed that seed germination percentage and germination rate were significantly affected (P<0.05) by salinity, alkalinity, temperature and their interactions. The seed germination percentage and germination rate were the highest under treatments at 10/20 ℃ or 15/25 ℃, and there was no significant difference between them. The seed germination percentage and germination rate decreased with the increasing of salinity and alkalinity concentrations and the deleterious effect of alkali stress was more severe than salt stress. Seed germination was significantly inhibited by treatment at 25/35 ℃ which also aggravated the inhibition of alkali and salt stress on seed germination. M. falcata had some tolerance to alkaline salts and high pH which germinated well under 25 mmol·L-1 Na2CO3 and 30 mmol·L-1 NaHCO3 treatments.
Screening and standardization of seed germination conditions of 9 wild grass species in southern China
Yi ZHANG, Pei-sheng MAO, Hong-tian SU, Qiu GAO, Mei-juan WANG, Man-li LI
2015, 9(11): 1854-1861. doi: 10.11829/j.issn.1001-0629.2015-0088
[Abstract](916) [FullText HTML] (112) [PDF 433KB](321)
In order to provide references for the standardization of seed germination test, nine domestic wild grass species including Arthraxon hispidus, Brachypodium sylvaticum, Capillipedium parviflorum, Eleusine indica, Eragrostis ferruginea, Leptochloa chinensis, Polypogon fugax, Sporobolus indicus var. purpurea-suffusus, Trisetum bifidum were selected to determine the optimal germination and pretreatment conditions by comprising and screening different temperature, illumination, pretreatment and counting time. The optimum germination conditions of A. hispidus and other 7 species seeds were screened according to germination testing, and the first and last counting time were determined based on the germination process. The pretreatment methods of dormancy breaking for A. hispidus and other seeds were recommended. Furthermore, it’s necessary to work out the effective methods for seed dormancy breaking of C. parviflorum and T. bifidum asthere was many fresh and ungerminated seeds during germination experiment.
Effects of simulated acid rain on diurnal changes of mulberry (Morus alba) photosynthesis
Yue HU, Qian ZHANG, Dong-bin SUN, Yu-wei SUN, Xiu-li ZHANG, Guang-yu SUN
2015, 9(11): 1862-1870. doi: 10.11829/j.issn.1001-0629.2015-0160
[Abstract](872) [FullText HTML] (70) [PDF 618KB](360)
In the present study, the response characteristics of gas exchange parameters for the diurnal variation of the mulberry leaf to simulated acid rain with different pH have been studied to reveal the mechanism and the effects of simulated acid rain on plant photosynthetic productivity. The results showed that net photosynthesis rate (Pn) present obviously photosynthetic depression at midday in treatment of CK (no acid rain), while three treatments of simulated acid rain could increase Pn at midday. During photosynthetic noon-break, stomatal conductance (Gs) and stomatal limitation value (Ls) decreased, but the intercellular CO2 concentration(Ci) increased, the results of correlation analysis showed that Pn and Ci was significantly negative correlation, which indicated that CO2 assimilation have been inhibited. The corresponding parameters under acid rain treatments showed similar change trends with CK excepted with that the Ci was lower than that of CK, and Gs was higher than CK, indicating that the simulated acid rain treatments could promote stomatal opening and CO2 assimilation of mulberry leaf during midday depression. Atmospheric temperature (T) significantly positively correlated with leaf saturation water vapor pressure deficit (Vpdl) and transpiration rate (Tr), respectively. However, there was significant negative correlation between T and atmospheric relative humidity (RH). Meanwhile,the value of RH was near the minimum value during midday depression of photosynthesis, which indicated that CO2 assimilation inhibition most come from water shortage. While Tr, Gs and Ls in treatments of simulated acid rain with pH≥4.5 were higher than that of CK, and the water use efficiency (WUE) in simulated acid rain had no significant difference with CK which indicated that simulated acid rain could promote mulberry leaf intercellular water supplying. In treatments of simulated acid rain with pH 3.5, the photosynthetic assimilation total (PT), average Pn and Gs were significantly lower than that of CK, while the corresponding parameters of pH 5.6 and pH 4.5 were higher than that of CK. These results suggested that treatments of simulated acid rain with pH≥4.5 had significant promoting effects on the photosynthesis of mulberry. In the region with mild acid rain pollution, the mulberry could be employed as plants for returning farmland to forest and landscape to absorb atmospheric SO2 and nitrogen oxides and adapt or lighten the atmosphere of acid rain pollution.
Sap flow dynamic variations of Hippophae rhamnoides and its response of meteorological factors
Feng-min LUO, Zhi-ming XIN, Jun-liang GAO, Ya-ru HUANG, Genbatu GE, Xin-le LI, Yu-guang HAO
2015, 9(11): 1871-1877. doi: 10.11829/j.issn.1001-0629.2015-0235
[Abstract](901) [FullText HTML] (106) [PDF 619KB](415)
In the present study, the sap flow of Hippophae rhamnoides and meteorological factors were measured in the Ulan Buh desertby using the TDP sap flow testing system and automatic meteorological station. The results showed that the daily variation curve of sap flow velocity in H. rhamnoides stem was in a multimodal distribution. The sap flow started at 07:50 and reached the maximum value around 09:10 which varied in a range of 292.07~340.27 g·h-1. The sap still flowed at night. The sap flow velocity in H. rhamnoides stem correlated with diameter and its daily accumulated sap flow amounts of diameter with 10.5, 8.3 and 7.5 cm was 16 593.26, 14 907.08 and 14 101.83 g, respectively. The change law of sap flow velocity was similar with that of environmental factors. The correlation analysis results revealed that the environmental factors affecting the variation of sap flow in H. rhamnoides were air relative humidity, air temperature, effective solar radiation, soil temperature in the depth of 10 cm and wind speed.
Effects of grazing and fencing on Stipa purpurea community biomass allocation and carbon, nitrogen and phosphorus pools on the northern Tibet Plateau alpine
Jiang-tao HONG, Jian-bo WU, Xiao-dan WANG
2015, 9(11): 1878-1886. doi: 10.11829/j.issn.1001-0629.2015-0076
[Abstract](926) [FullText HTML] (96) [PDF 658KB](415)
The “grassland enclosure project” is an important measure to improve ecological and environmental quality of degradation grassland and promote economy sustainable development of pastoral area. In the present study, the Stipa purpurea community biomass allocation and carbon(C), nitrogen(N) and phosphorus (P) pools were investigated in three utilization management blocks including free grazing grassland (FG), four years enclosed grassland(F4) and eight years enclosed grassland (F8) on the northern Tibet Plateau alpine. The results showed that aboveground biomass of S. purpurea community in FG, F4 and F8 were 46.12, 146.40 and 256.44 g·m-2, respectively. Root biomasses in layer of 0-15 cm were 274.74, 214.87 and 764.59 g·m-2 and root biomasses in layer of 15-30 cm were 17.80, 17.56 and 31.64 g·m-2 for these three treatments, respectively. These results suggested that enclosure significantly increased (P<0.05) the community growth. S. purpurea and Carex moorcroftii had the highest biomass in F4 (P<0.05). Enclosure significantly increased plant C, N and P pools of S. purpurea community and F8 had the highest nutrient pools (P<0.05) among the three blocks. Our research provide basic data for revealing plant biomass and nutrient allocation response to grassland utilization management and evaluating ecological effects of “grassland enclosure project”.
Effects of soil conditioners on growth of different forage species and soil moisture in karst region
Xing-yan XIAO, Lei-yi ZHANG, Fang LIU, Bin YAO, Jian LONG
2015, 9(11): 1887-1891. doi: 10.11829/j.issn.1001-0629.2015-0143
[Abstract](834) [FullText HTML] (38) [PDF 442KB](337)
In the present study, the effects of soil conditioners on growth of different forage species including Paspalum thunbergii, Lolium perenne, Dolichos lablab and soil moisture on karst were evaluated using pot experiments. Under the same soil conditions and water management, there were obvious differences (P>0.05) between the biomass of these three forages which were D. lablab >P. thunbergii>L. perenne whereas the soil moisture change in the opposite order and differed significantly. The soil moisture in the field of P. thunbergii increased by 15.4% and 31.1% compared with that of L. perenne and D. lablab, respectively. The soil water holding capacity of P. thunbergii was obviously higher than that of D. lablab. With the conditions of no precipitation for 10 days and 5% straw biochar, the soil moisture of P. thunbergii, D. lablab and L. perenne, increased 17.9%、17.4% and 19.8%, respectively. The experimental results indicated that the application of P. thunbergii could increase the soil moisture and the improvement can be promoted by adding straw biochar.
Effects of double mulched furrow-ridge cropping with film and straw on soil nutrients balance and maize yield in semiarid area of China
Feng-ke YANG, Bao-lin HE, Li-gong ZHANG, Ying-ping GAO
2015, 9(11): 1892-1901. doi: 10.11829/j.issn.1001-0629.2015-0061
[Abstract](997) [FullText HTML] (43) [PDF 625KB](407)
Split-plot designed field experiment was carried out to test the effects of film straw double mulched furrow-ridge cropping on soil nutrient balance and maize yield at Zhuanglang station of Gansu Academy of Agricultural Sciences in semiarid area of China during 2011-2013.The results showed that this cropping model had superimposed and amplified the effects of both the soil moisture and temperature increase of film mulch, the soil moisture and temperature adjust and maintain of straw mulch and the water harvesting of furrow-ridge cropping that significantly increased the 0-25 cm soil layer average temperature and 0-100 cm soil layer moisture by 3 ℃ and 3.71 percentage points compare with that of bare land cropping, which in turn effectively accelerated straw decomposition and nutrients release and resulted in an apparent effect of increase soil organic matter and available nutrients content after the second year applying. The three year average contents of soil organic matter, total nitrogen, phosphorus, potassium and available nitrogen, phosphorus, potassium at 0-40 cm soil layer had increased by 1.19%, 3.08%, 9.14%, 6.78%, 6.28%, 1.85%, 7.10% compare with that of bare land cropping, respectively. Soil moisture-temperature environment and fertility improvement had optimized crop growth habitat and effectively boosted maize growth and development, with significantly improving in yield traits of plant height, ear position, double ear rate, grain number per ears and 100-grain weight resulted in 64.22% yield increase than that of bare land cropping. So the crop model about film-mulched furrow-ridge cropping with straw returning underneath is recommended as the effective way of soil fertility improvement and maize efficient growth in 550 mm precipitation semiarid area of China.
The growth evaluation of introduced leguminous forage Crotalaria alata in plain area of northern Xinjiang
2015, 9(11): 1902-1906. doi: 10.11829/j.issn.1001-0629.2015-0121
[Abstract](737) [FullText HTML] (39) [PDF 453KB](289)
The adaptability and agronomic traits of annual legume forage Crotalaria alatawhich introduced from Uzbekistan in 2012 were evaluated in 2013 and 2014 in Hutubi and Fukang of Xinjiang,respectively. The results showed that C. alatagrew grew well with the plant height of 130~180 cm and roots had nodules to fix nitrogen. During early flowering season, the content of crude protein (CP) was the highest which was 23.02%,the content of crude fiber (CF) was 20.3%. The plant was rich in nutrition containing 17 kinds of amino acids. The fresh yields of forage were 23 833.5 and 21 750.0 kg·ha-1 in Hutubi and Fukang, respectively. Seed yields were 366 and 385.3 kg·ha-1, respectively. Integrative evaluation showed that C. alatais are suitable for extension in northern Xinjiang plain area.
Effects of PMSG on estrus synchronization and reproductive rate of Gansu alpine fine-wool sheep
Cheng LI, Li-ping ZHANG, Jian-ping WU, Xu-yin GONG, Ting LIU, Jian-wei TONG
2015, 9(11): 1907-1912. doi: 10.11829/j.issn.1001-0629.2015-0009
[Abstract](786) [FullText HTML] (46) [PDF 496KB](311)
In the present study, the rates of both estrus synchronization and reproduction of Gansu alpine-fine-wool ewes were investigated after CIDR(Intravaginal Progesterone Insert) and PMSG(Pregnant Mare Serum Gonadotropin) combination treatment in Kangle Town, Sunan County, Gansu Province. The ewes had the highest estrus rate (P<0.05) in 48 hours under treatment with 550 IU PMSG injection after 12.5 days of using CIDRs and removing them in the 14th day compared with other treatments. The ewes had the highest reproductive rate (P<0.05) under treatment with 600 IU PMSG injection after 13 days of using CIDRs and removing them at the same time. However, the former treatment was optimal if considering both reproductive rate and economic benefits which had 773.7 CNY net income of per ewe.
Effects of fenvalerate on detoxifying enzyme activities of Oedaleus infernalis
Yong-ling JIN, Su-ning YANG, Bin CONG, Li-yan WANG
2015, 9(11): 1913-1919. doi: 10.11829/j.issn.1001-0629.2015-0107
[Abstract](824) [FullText HTML] (73) [PDF 521KB](333)
In order to determine the effects of fenvalerate on detoxification enzymes activities of Oedaleus infernalis, the enzyme inhibitors (piperonyl butoxide, PBO; three phosphoric acid phenyl esterm, TPP; diethylmeteate, DEM) effects synergy with in vivo enzyme activities in insects from different source were measured. The results showed that the LD50 of fenvalerate to in door population source O. infernalis was 4.38×10-3 μg·locust-1, to the field population source HG, LD and ZY in the Heilongjiang were 7.30×10-3 μg·locust-1, 7.21×10-3 μg·locust-1 and 22.98×10-3 μg·locust-1, respectively, which had the resistance ratio of 1.67, 1.65 and 5.25. Both PBO and TPP on indoor and field population source ZY to fenvalerate had synergistic effects, which had the synergistic ratio 2.16 and 3.91, 2.00 and 2.15, respectively. Comparing with field population source ZY, the activities of esterase and multiple function oxidase in the indoor population source significantly increased (P<0.05). After the induction of fenvalerate, the esterase activities rising ratios of field population source ZY and indoor population source were 2.25 and 1.59; and the multiple function oxidase activities rising ratio were 1.21 and 1.45, respectively. These above results showed that the activities of esterase and multiple function oxidase increased with the decreasing of sensitivity of O. infernalis to fenvalerate which suggested that esterase and multiple function oxidase were involved in the metabolism of fenvalerate in oedaleus infernalis, and the two enzymes wereone of the reasons for fenvalerate resistance.
Impacts of grassland ecological compensation on households in China
Bo YANG, Zhi-biao NAN, Zeng TANG
2015, 9(11): 1920-1927. doi: 10.11829/j.issn.1001-0629.2015-0048
[Abstract](844) [FullText HTML] (64) [PDF 581KB](450)
In order to restore and protect the grassland ecological environment which had been degraded, China government has carried out extensive grassland ecological compensation system which including grazing restrictions, returning cropland to forestry and grass, rewards and compensation of grassland ecology protection, and so on. The degraded grassland has recovered and the height, coverage and hay yield of grassland has been improved after over ten years of grassland ecological compensation system application. The present paper summarized the impacts of grassland ecological compensation on farmers and herders as household is the fundamental unit of ecological compensation and their responses were closely related to the persistence of ecological compensation. The results showed that grassland ecological compensation had a positive impact on household income and agricultural structure. However, the experience was still in the immature stage. Grassland ecological compensation had following questions including unreasonable compensation period and rewards standard; outdate livestock production model and large funding gap; high risk of pen feeding; difficulty of surplus labor force shift; and lack of technical compensation. Following suggestions were proposed based on the above problems: establishing reasonable standards, broadening financing channels; improving the social security system, developing intensive animal husbandry, adding technical offset, and extending period of subsidy and developing follow-up industry.