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2018 Vol.35(4)

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2018, 12(4): 712-712.
[Abstract](631) [PDF 1063KB](299)
Orginal Article
Spatial-temporal variations in NDVI in vegetation-growing season in Qinghai based on GIMMS NDVI 3g.v1 in past 34 years
Zi-jun Dai, Xia Zhao, Guan-wen Li, Xing-chun Wang, Long-hui Pang
2018, 12(4): 713-725. doi: 10.11829/j.issn.1001-0629.2017-0387
[Abstract](1431) [FullText HTML] (286) [PDF 2827KB](214)
Under the influence of climate change and human activities, the ecological environment in Qinghai Province has changed markedly. In this context, taking GIMMS NDVI3g.v1 as the data source, we analyzed temporal and spatial changes in NDVI of the vegetation coverage area in Qinghai Province from 1982 to 2015, using the Theil-Sen Median trend analysis and Maan-Kendall test. Both the trend analysis and R/S analysis were superimposed to study the persistent characteristics of NDVI change during the vegetation growth season, and reveal the regularity of vegetation response to climate change and human activities. The results showed that: 1) Vegetation NDVI in Qinghai Province increased from the Northwest to Southeast in the past 34 years, and the coefficient of variation indicated that a larger volatility region was concentrated in the lower NDVI region of the Qaidam Basin and northwest of the Qingnan pastoral area; the volatility was concentrated in the eastern part of the Qilian Mountains, eastern agricultural area, and southwest of Qingnan pasture area with high vegetation NDVI. 2) In the past 34 years, the overall NDVI of vegetation in Qinghai showed an increasing trend; growth rate was 0.38%·10 a-1, the change in NDVI was obvious in phases, and there were two abrupt changes in 1994 and 2000. 3) The area of vegetation improvement in Qinghai Province (75.4%) from 1982 to 2015 was much larger than that of vegetation degradation (24.6%), of which the significant improvement area represented 40.9% of the area covered by vegetation, and the degradation zone showed a significant shift in space over time. 4) The Hurst index showed that the reverse trend of vegetation change in Qinghai Province was remarkably persistent; the trend analysis and Hurst index obtained by superposition showed that 13.7% of the area affected by degradation was enhanced from degradation to improvement, and 44.3% of the area from improvement to degradation; future trends of 41.5% of the area could not be determined, and only 0.2%-0.3% of area was between continuous improvement and sustained degradation. 5) The NDVI of vegetation growth in Qinghai Province was affected by climate change and human activities, and the response of different vegetation types to climate change was quite different.
Change in NDVI of northern Tibet and root cause analysis from 1982 to 2014
Lhaba, Droma Lhaba, Yangzom Dekey, Dron Lha
2018, 12(4): 726-736. doi: 10.11829/j.issn.1001-0629.2017-0369
[Abstract](923) [FullText HTML] (192) [PDF 1984KB](111)
Vegetation growth in Nagqu exhibited an marked variation in status in the last 5 years under the grassland reform ecological compensation project. GIMMS, MODIS-NDVI, meteorological observations, and data on social statistics from 1981-2014 have been used to investigate spatial and temporal variations in vegetation along with the effect of meteorological factors and human activities on vegetation distribution. The results showed that interdecadal variations in vegetation exhibited a periodic increasing tendency, while interannual variation did not change substantially in the past 34 years. The trend showed by vegetation in most parts of Nagqu indicated a stable variation, and the areas constituted 57.82% of the total region; areas with slight improvement and decrease constituted 32.84% and 14.06%, respectively, and areas with significant variation represented 7%. Areas with serious degradation were mainly concentrated in the eastern and southeastern counties of Nagqu, while stable areas were situated to the west of the middle region and northern counties; vegetation in certain areas even tended to improve. Variations in precipitation, air temperature, and livestock density constitute the main reason for the uneven spatial distribution of vegetation in Nagqu.
Simulation and evaluation of forage height in alpine meadow grassland in headwaters of the Yellow River
Jian-peng Yin, Jin-long Gao, Qi-sheng Feng, Jing Ge, Bao-ping Meng, Shu-xia Yang, Tian-gang Liang, Xiao-ping Meng
2018, 12(4): 737-748. doi: 10.11829/j.issn.1001-0629.2017-0251
[Abstract](811) [FullText HTML] (81) [PDF 892KB](143)
Canopy height in grassland is an important factor for reflecting growth status, and is closely related to monitoring of aboveground biomass and grazing capacity evaluation as well. Presently, accurate remote sensing methods for monitoring canopy height in natural grassland communities are still lacking. In this study, height estimation models based on MODIS vegetation indices, canopy height model, and grassland hyperspectral reflectance were established, and assessed in the source region of the Yellow River, individually. The results showed that: 1) NDVI was most sensitive to grassland canopy height in 12 MODIS vegetation indices. However, the R2 values of four regression models derived from NDVI were low, which were 0.203~0.241. The NDVI exponential model (y=0.789e3.186x,R2=0.241) had the best fitting effect; however, inversion error was greater (RMSE=4.2 cm, CVRMSE = 45.7%); 2) The accuracy of the canopy height model in alpine meadow was low (RMSE=5.8 cm, CVRMSE=62.1%); 3) There was a significant negative correlation between height of alpine meadow community and canopy spectral reflectance ranging within 519.4~583.17 nm band (P0.05). The linear model y=-156.375x+20.384 (R2=0.489, RMSE=3.5 cm) based on R'510.59 was suitable for estimating the grassland canopy height in alpine meadows.
Effect of four native plant species on soil properties in desertified alpine meadow of the Tibetan Plateau
Xiao-xi Zhang, Kai Zeng, Yi-min Cai, Sai-nan Ma, Yang Song, Lin Liu, Dong-ming Chen, Chun-mei Zhou, Fei-da Sun, You-jun Chen
2018, 12(4): 749-759. doi: 10.11829/j.issn.1001-0629.2017-0376
[Abstract](902) [FullText HTML] (122) [PDF 980KB](153)
Desertification has already become a serious threat to alpine meadows in southeastern Tibetan Plateau, and to provide scientific evidence for selecting adaptive plant species and a reasonable direction for recovering desertified alpine meadows, the effects of four native plant species, including Rhodiola rosea, Kengyilia rigidula, Elymus nutans, and Salix cupularis, on soil physicochemical properties, soil enzymes, and soil microbial biomass were explored in this study. The results showed that: 1) After five years of vegetation restoration, soil moisture increased significantly (P<0.05), and increased the most (by 357.70%) in the treatment with E. nutans among the four plant species; meanwhile, both soil pH and bulk density decreased at different levels for the different species; 2) Activities of soil enzymes related to carbon, nitrogen, and phosphorus cycles increased significantly (P<0.05), and the activities of cellulase, peroxidase, sucrase, protease, and phosphatase in the treatment with R. rosea, which were 3.19, 1.98, 3.22, 1.87, and 4.59 times that of the control, respectively, exhibited the highest values than the others; 3) Soil microbial biomass carbon (MBC) and nitrogen (MBN) increased significantly (P<0.05), and soil MBC, MBN, and microbial biomass carbon to nitrogen ratio (MBC/MBN), which were 4.39, 3.46, and 1.27 times that of the control, respectively, were the highest in the treatment with R. rosea; 4) The correlations between soil enzyme activity, soil physicochemical properties, and microbial biomass factors were significant in the two treatments with R. rosea and S. cupularis; however, these correlations were not observed in the treatment with E. nutans. The results indicated that R. rosea could embody the best approach to restore desertified alpine meadows among the four native plant species after five years of planting.
Cadmium tolerance and absorption characteristic of herbaceous plants
Xi-ming Li, Jin-bo Li, Gui-long Song, Shi-gang Li, Xue-hua Puyang
2018, 12(4): 760-770. doi: 10.11829/j.issn.1001-0629.2017-0308
[Abstract](752) [FullText HTML] (55) [PDF 640KB](123)
Thirty-five varieties of herbaceous plants were selected for studying tolerance and accumulation characteristics of cadmium in pot experiments using 10 mg·kg-1 cadmium treatments. The plants were grown under conditions sheltered from rain. We found that the herbaceous plants had good tolerance against 10 mg·kg-1 cadmium stress, and that the growth of only nine species was significantly inhibited in the experiment on herbaceous plants. In addition, root/shoot ratio decreased significantly (P<0.05) in two species only. Cadmium absorption and accumulation differed among the experimental plants, and the translocation capacity of leguminous plants and warm-season turfgrass were superior to that of cool-season turfgrass. The highest cadmium content in shoots and roots were found in Crowtoe (Lotus corniculatus) and Kentucky bluegrass (Poa pratensis), respectively. The highest cadmium translocation factor was found in Lyme grass (Elymus dahuricum). The result of clustering analysis based on cadmium accumulation in shoots indicated that two varieties of annual ryegrass (Lolium multiflorum) have the highest cadmium accumulation among the herbaceous plants studied.
Effect of different land use types on soil aggregates microbial biomass and community composition in the loess hilly region of west Henan
Jing Liu, Yue-wei Zhang, Qiao-ming Zhang, Shao-jun Xu
2018, 12(4): 771-780. doi: 10.11829/j.issn.1001-0629.2017-0211
[Abstract](818) [FullText HTML] (55) [PDF 694KB](85)
Microbial biomass and community composition in aggregates of different land use types in the loess hill region of west Henan were analyzed by fumigation extraction method and phospholipids fatty acids (PLFA) biomarkers. Microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) contents were the highest in aggregate of 0.25~2.00 mm and lowest in 0.053~0.250 mm. Compared with the farmland, the MBC and MBN contents in >5 mm, 2~5 mm and 0.25~2.00 mm aggregates of broad-leaved mixed forestland, Robinia pseudoacacia plantation forestland and shrub-grass land were significantly increased(P<0.05), which in orchard and farmland were no significant difference(P>0.05). The PLFA contents of bacteria were the highest in the 0.25~2.00 mm aggregates, however, the highest proportion of bacteria to total PLFA were found in 0.053~0.250 mm aggregates in all different land use types. The PLFA contents of fungi and its proportion to total PLFA in the >5 mm aggregates were the highest and induced with the decrease of the aggregates size. The contents of MBC and MBN present a notable positive correlation with the PLFA contents of the bacteria and fungi(P<0.05 or P<0.01). Compared with the farmland and orchard soil, the contents of fungi in>5 mm, 2~5 mm and 0.25~2.00 mm aggregates of broad-leaved mixed forestland, R. pseudoacacia plantation forestland and shrub-grass land increased significantly. To sum up, soil microbial biomass and fungi PLFA contents in >0.25 mm aggregates of broad-leaved mixed forestland, R. pseudoacacia plantation forestland and shrub-grass land were significantly increased compared with farmland and orchard.
Effect of climate warming and nitrogen deposition on net photosynthetic rate of alpine plants on Qinghai-Tibet Plateau
Jing Feng, Xiang-feng Zhang, Shi-kui Dong, Jin-bo Zhao, Zhen-zhen Zhao, Yu-hui Han, Wei Sha, Ming-yue Yang, Shuai Li, Hao Shen
2018, 12(4): 781-790. doi: 10.11829/j.issn.1001-0629.2017-0338
[Abstract](1114) [FullText HTML] (117) [PDF 1542KB](92)
Simulated warming and nitrogen deposition experiments were conducted to examine the responses of the net photosynthetic rate of key dominant plants in four types of alpine grasslands, including alpine meadow, alpine steppe, alpine desert, and artificial grassland on Qinghai-Tibetan Plateau by using Li-6400. There were seven treatments: control [CK, 0 kg·(ha·a)-1], low nitrogen Ⅰ [NⅠ, 8 kg·(ha·a)-1], low nitrogen Ⅱ [NⅡ, 24 kg·(ha·a)-1], medium nitrogen [NⅢ,40 kg·(ha·a)-1], high nitrogen Ⅰ [NⅣ, 56 kg·(ha·a)-1], high nitrogen Ⅱ [NⅤ, 72 kg·(ha·a)-1], warming [W, 0 kg·(ha·a)-1], and the interaction of warming and nitrogen addition [W-NⅠ, 8 kg·(ha·a)-1]. The results showed that 1) the net photosynthetic rate of Dracocephalum heterophyllum and Stipa capillata increased initially and then decreased with the increasing gradients of warming and nitrogen addition. With increasing nitrogen deposition, the net photosynthetic rate of Artemisia scoparia, Silene aprica, Kobresia humilis, Poa crymophila, and P. attenuate in the alpine meadow increased markedly. 2) The net photosynthetic rate of Thermopsis lanceolate, Iris lactea var. chinensis, and Potentilla multifida increased with nitrogen deposition, while that of K. humilis, Plantago depressa, A. scoparia, K. capillifolia, P. crymophila, Pedicularis kansuensis, Elymus nutans, and Dracocephalum heterophyllum decreased with nitrogen deposition. 3) The net photosynthetic rate of T. lanceolate, P. crymophila, and Aster tataricus in the artificial grassland decreased initially and increased thereafter with the increase of nitrogen deposition. 4) The net photosynthetic rate of Blysmus sinocompressus in soil-salinization grassland decreased, while that of Ceratoides compacta in alpine desert and Leymus secalinus in the transitional zone between soil-salinization grassland and desert increased with the experimental warming.
Effect of grazing systems on soil seedbank:A case study of an alpine meadow in the eastern Qinghai-Tibet Plateau
Bo Shen, Qing-qing Ma, Yun-xiang Cheng, Sheng-hua Chang, Yue Li, Jin-mei Guo, Fu-jiang Hou
2018, 12(4): 791-799. doi: 10.11829/j.issn.1001-0629.2017-0271
[Abstract](822) [FullText HTML] (59) [PDF 561KB](112)
In order to understand the response of soil seed banks to different grazing regimes, we investigated the seed density and vertical distribution of soil seed banks, and the relationship between soil seed banks and the aboveground vegetation change in the warm- and cold-season pasture of an alpine meadow in the Maqu area of the Qinghai-Tibet plateau. The results showed the following: 1) In the soil seed bank of the warm-season pasture, there were 12 species subjected to light grazing, with seed density 2 307.66 seed·m-2; there were six species subjected to severe grazing, with seed density 1 065.08 seed·m-2; there were five species subjected to restricted grazing, with seed density 828.38 seed·m-2; the species richness and density of lightly grazed species were significantly higher than those of heavily grazed species. 2) In the cold-season pasture, there were 12 species subjected to light grazing, with seed density 3 786.88 seed·m-2; there were eight species subjected to severe grazing, with seed density 621.15 seed·m-2; there were five species subjected to restricted grazing, with seed density 532.53 seed·m-2. The amount of light grazing was less than that of heavy grazing. 3) The Shannon-Wiener, Pielow, Simpson and Margarlef indices of the soil seed bank under light grazing were higher than those under heavy grazing conditions. Both in warm- and cold-season pastures, the similarities between the soil seed bank and aboveground vegetation under different grazing intensities were lower than 0.3. 4) The seeds were mainly concentrated in the shallow soil layer (0-5 cm), and the seed density decreased rapidly with an increase in soil depth.
Effect of grazing on quantitative characteristics of Caragana microphylla population
Li-hong Wang, Yue Wang, De-kai Wang, Li-na Xie, Cheng-cang Ma
2018, 12(4): 800-806. doi: 10.11829/j.issn.1001-0629.2017-0368
[Abstract](944) [FullText HTML] (62) [PDF 583KB](98)
To understand the effect of grazing on the quantitative characteristics of Caragana microphylla population, we investigated the shrub cover, density, height, and total biomass of C. microphylla under non-grazing, light-grazing, moderate-grazing, and heavy-grazing treatments. The results showed that with increase in grazing intensity, the density of the C. microphylla shrub increased initially, and then decreased; however, there was no significant difference among the different treatments (P=0.11), suggesting, to some extent, that moderate grazing benefitted the reproduction of C. microphylla. Contrastingly, grazing significantly reduced the shrub cover, height, and total biomass of C. microphylla (P<0.05), suggesting that grazing had an obvious negative effect on the shrub. Based on the quantitative characteristics of C. microphylla population under different grazing treatments, we suggested that moderate grazing intensity should be moderate-intensity grazing in desert steppes
Niche characteristics of the primary understory populations of a Picea asperata plantation in the subalpine region of Gansu Province
Yi-ming Feng, Xue-long Chen, Rui Qi, Yang Zhao, Ya-li Hou, Qian-qian Yan, She-qin Li, De-cai Xu
2018, 12(4): 807-815. doi: 10.11829/j.issn.1001-0629.2017-0236
[Abstract](904) [FullText HTML] (122) [PDF 573KB](85)
Based on the data from 110 plots obtained from field surveys, and using the Levins and Shannon-Wiener niche breadth index and Levins niche overlapping index, a quantitative analysis was conducted on the niche characteristics of 30 species, including 15 shrub species and 15 herb species in the understory populations of a spruce plantation in the subalpine region of Gansu Province. In the shrub layer, Rubus pungens, Sinarundinaria nitida and R. amabilis had a greater niche breadth than other species. In herb layer, Fragaria orientalis, Dactylis glomerata, and Cardamine tangutorum had greater niche breadths. These species were highly adaptable, had broad habitats, and tended to be generalist species. The populations with greater niche breadth exhibited smaller niche overlap, whereas those with smaller niche breadth exhibited larger niche overlap. Niche breadth and niche overlap did not have a positive direct liner relationship. In conclusion, niche overlap of the primary understory populations in a spruce plantation was relatively low, and interspecific competition was not intense. Betula albo-sinensis and Geranium wilfordii were more aggressive than other species based on their eco-response, and they will develop as the dominant species of main understory population in the spruce plantation in the future.
Critical concentration of salt stress in Stenotaphrum secundatum
Yu-jiao Xu, Yu-jie Zhou, Ying Luo, Li Liao, Chang-jun Bai, Zhi-yong Wang
2018, 12(4): 816-821. doi: 10.11829/j.issn.1001-0629.2017-0347
[Abstract](1150) [FullText HTML] (162) [PDF 879KB](100)
The objective of this study was to identify the semi-lethal concentrations of salt stress in Stenotaphrum secundatum using hydroponics to provide a theoretic background for screening salt tolerance of different accessions. The experiment was carried out at 10 concentration gradient treatments, which were 0, 35, 70, 105, 140, 175, 210, 245, 280, and 315 mmol·L-1. To investigate morphological indicators of S. secundatum, plants were treated after 28 days to determine the semi-lethal concentration of NaCl. The results showed that different treatments had significant differences (P<0.05). With the increase in the salt concentration of the treatment, four morphological indexes, which were leaf color, turf quality, stolon length, and dry matter weight increased significantly (P<0.05), whereas leaf firing decreased (P<0.05). Using a linear regression equation, the semi-lethal concentration was found to be 185 mmol·L-1, when the rate of leaf firing was 50%. These results can provide a scientific basis and direction for the later screening of S. secundatum germplasm.
Effect of ethephon on physiological indexes of Kentucky bluegrass under drought stress
Yong-chao Sui, Nuan Leng, He-nan Jiang, Xue Wu, Zhi-hao Luo, Hao-kun Ye, Yu-yu Feng, Li-xin Xu
2018, 12(4): 822-828. doi: 10.11829/j.issn.1001-0629.2017-0348
[Abstract](839) [FullText HTML] (101) [PDF 508KB](101)
Kentucky bluegrass cultivar “Nuglade” plants were divided into two groups-ethephon treated (ETH) and non-ethephon treated control group (CK). These groups of plants were subjected to three treatment conditions: well-watered, drought, and re-watering. The effects of ethephon on the drought responses of Kentucky bluegrass were studied by measuring physiological indicators such as electrolyte leakage and chlorophyll, soluble protein, and malondialdehyde (MDA) content. Under drought stress,‘Nuglade’ treated with ethephon was able to maintain a higher leaf relative water content of 23.47% (with that of the control group being 11.5%) and lower membrane stability expressed as EL 68.1% (with that of the control group being 90.7%). During re-watering, the EL of the ethephon group recovered to that of unstressed plants. Under drought stress, the MDA content in ETH plants was lower than that in the control group. The SP content of the ETH group was also higher than that in the CK group under re-watering conditions; Our results indicated that spraying ethephon on the leaves of Kentucky bluegrass could improve performance and promote the recovery of physiological indexes during re-watering.
Salt stress tolerance analysis of rgMT gene transformed Medicago sativa
Chang Xu, Hao He, Guo-liang Li, Shu-mei Jin
2018, 12(4): 829-838. doi: 10.11829/j.issn.1001-0629.2017-0321
[Abstract](1004) [FullText HTML] (56) [PDF 2153KB](83)
In this study, a metallothionein gene (rgMT) cloned from rice was transformed into Medicago sativa cv. “Nongjing No. 1” using the Agrobacterium-mediated method. Resistant seedlings were tested by PCR and northern blotting, and the results showed that rgMT gene was transformed into M. sativa genome, and was normally expressed in transgenic plants. We compared the phenotypic traits and physiological characteristics of the non-transgenic line (wild-type, WT) and transgenic lines under different concentrations of NaCl and NaHCO3. The growth of the WT was inhibited severely, and even death was observed, but the transgenic lines were just slightly inhibited. The proline and superoxide dismutase (SOD) contents of the transgenic lines were significantly higher than those of the WT (P<0.05), and the relative membrane permeability of the transgenic lines were significantly lower than those of the WT under salt stress. More H2O2 accumulated in the leaves of the WT compared to in those of transgenic lines. This result showed that rgMT was expressed in M. sativa, and the transgenic lines had a greater salinity tolerance than the WT.
Effect of seed soaking with Epichloë fermentation broth on germination characteristics in perennial ryegrass under drought stress
Jing Liu, Jing-le Zhou, Zhen-jiang Chen, Xue-kai Wei, Tao Li, Chun-jie Li
2018, 12(4): 839-847. doi: 10.11829/j.issn.1001-0629.2017-0268
[Abstract](913) [FullText HTML] (56) [PDF 662KB](119)
To explore the in vitro effect of Epichloë on the drought resistance in perennial ryegrass seeds during germination, the seeds were soaked in three species of Epichloë (E. gansuensis, E. bromicola, and Epichloë sp.) fermentation broth, to test the germination index of seeds under different concentrations of polyethylene glycol (PEG) through the paper germination test. The results showed that the seed germination rate, germination force, germination index, vigor index, seeding length, and seedling moisture content were decreased, the mildew rate was increased first and then decreased when the PEG concentration increased, and the root length of seedlings had a peak value at -0.6 MPa. The seeds inactivated and could not germinate when the concentration of PEG was -1.2 MPa. Compared to the control, soaking in Epichloë fermentation broth significantly (P<0.05) promoted seed germination, seedling growth, and root growth, and effectively reduced the mildew rate (P<0.05). Compared to seed soaking with Achnatherum inebrians Epichloë fermentation broth, the seed germination index, vigor index, seedling water content, seedling length, and root length of perennial ryegrass were greater than those in the Elymus dahuricus and Festuca sinensis experiments. In short, the fermentation broth of Epichloë had a certain effect on the germination of perennial ryegrass seeds under drought stress, and the effect of the A. inebrians fermentation broth was the strongest of the three different kinds of fermentation broth.
Effect of drought and rewatering on the photosynthetic characteristics in Morus alba leaves
Zhi-yuan Teng, Xu-han Zhang, Hui-hui Zhang, Yao Ma, Xiu-li Zhang, Guang-yu Sun
2018, 12(4): 848-856. doi: 10.11829/j.issn.1001-0629.2017-0362
[Abstract](741) [FullText HTML] (52) [PDF 846KB](89)
In order to detect the effects of drought and rewatering on the photosynthetic capacity and adaptive mechanism in mulberry leaves, a mulberry variety named ‘Qiuyu’ was employed as the experimental material, and the characteristics of photosynthesis, and fluorescence were investigated using pot tests with a water control (CK). The results showed that the water contents in the potted mulberry plant leaves were significantly lower than that in the CK; leaf wilting, curling and drooping, and the leaf base angle was increased when the soil water content was reduced to 26.7%, and the net photosynthetic rate, stomatal conductance, and transpiration rate were close to zero, while the values of stomatal limitation and intercellular CO2 concentration were increased. In addition, the excess light energy, ratio of dependent thylakoid membrane on both sides of the proton gradient, proportion of xanthophyll cycle, fluorescence quantum yield, heat dissipation quantum yield, and the original fluorescence were increased. Additionally, the maximum fluorescence, proportion of absorbed light energy in to the photochemical reaction yield, and the electron transport rate were decreased. After rewatering, the indicators of leaf growth, main parameters of photosynthesis and fluorescence in the mulberry leaves recovered quickly and returned to close to those in the CK. Our results indicated that the decrease in the net photosynthetic rate under drought stress might be caused by the stomatal and non-stomatal limitations. The PSII response center was partly inactivated, the excitation energy in mulberry seeding leaves was reduced; these responses mainly depended upon increasing ratios of the xanthophyll cycle and the quantum yields of fluorescence and heat dissipation. After rewatering, the photosynthetic apparatus in the mulberry leaves had a perfect mechanism for adapting to drought stress and repairing after injury, which could help mulberry to recover quickly in a shorter time.
Construction of a yield prediction model for whole crop maize on the basis of climatic data in South Korea
Jing-lun Peng, Juan Wang, Moon-ju Kim, Mu-hwan Jo, Byong-wan Kim, Kyung-il Sung
2018, 12(4): 857-866. doi: 10.11829/j.issn.1001-0629.2017-0359
[Abstract](796) [FullText HTML] (92) [PDF 1189KB](127)
The objective of this study was to construct a dry matter yield (DMY) prediction model for whole crop maize (WCM, Zea mays) on the basis of climatic data by location in South Korea. The forage crop and climatic data were collected from the reports of national research projects on forage crops and the website of Korea Meteorological Administration, respectively. The data set (n=775) of 22 years(1988-2011) was used to construct the model after a four-step data preparation. Two optimal climatic variables were selected through stepwise multiple regression analysis, with DMY as the dependent variable. Subsequently, using a general linear model, the final model, whichincluded the two climatic variables and cultivated location (in the form of a dummy variable), was constructed as follows: DMY=11.298SHAGDD-3.651SHP+1 089.870+Location, where SHAGDD refers to seeding-harvest accumulated growing degree days and SHP, seeding-harvest precipitation. The homoscedasticity and assumption that the mean of the residualsequal to zero was satisfied and the reliability of the model were good,since most scatters of the predicted DMY values fell within the 95% confidence interval. The model was tested using residual diagnostics and 10-fold cross-validation. The results showed that the variables related to temperature and precipitation had significant effects on the WCM yield. Therefore, accurate determination of sowing and harvest dates is important to ensure that the crops grow under appropriate accumulative temperature conditions. Furthermore, land with good drainage and cultivars with strong tolerance to water logging are necessary for the cultivation of WCM in South Korea because of excessive precipitation during the growing season.
Comparative study on the production performance of 13 Stylosanthes germplasms
Lin-ling Yan, Yu Zhang, Chang-jun Bai
2018, 12(4): 867-875. doi: 10.11829/j.issn.1001-0629.2017-0385
[Abstract](659) [FullText HTML] (67) [PDF 540KB](75)
In order to screen Stylosanthes varieties of excellent comprehensive properties, the adaptability of 13 Stylosanthes germplasms were studied by testing the height, survival rate, stem/leaf ratio, anthrax disease, hay yield, seed yields, 1000-grain weight, and nutrition components from 2011 to 2014; the production performances were compared and evaluated by membership function. The results showed that their initial blossoming stage was from September to November. The survival rate of TPRC2001-84 was the highest, up to 72.6% followed by TPRC 2001-81 with 56.6%. The 13 Stylosanthes germplasms were all resistant to anthracnose. Forage DM yield of TPRC 2001-84 was the highest, up to 15 968 kg·ha-1, followed by TPRC2001-81 and Reyan No. 20, 12 206, and 12 724 kg·ha-1, respectively. It was also found that the highest seed yield was in TPRC 2001-85, up to 56.7 kg·ha-1, and the highest crude protein content was in Reyan No. 21 with up to 21.57%. The highest crude fat and phosphorus content was in Reyan No. 20 and Reyan No. 21. The highest calcium content was in Reyan No. 21. The highest potassium content was in TPRC 2001-85. Therefore, among all the Stylosanthes germplasm, TPRC 2001-84, Reyan No. 21, TPRC 2001-85, and TPRC 2001-1 had been found to have excellent production performance and were suitable for promotion and cultivation in the tropical area.
Study on the optimal harvest time of Secale cereale‘Ganyin No.1’ in cold regions of Tianzhu County
Xiang-jun Meng, Tian-hu Han, Hui-juan Wu, Hui-yun Yu
2018, 12(4): 876-881. doi: 10.11829/j.issn.1001-0629.2017-0225
[Abstract](804) [FullText HTML] (60) [PDF 507KB](84)
Determination of the best possible harvest time is important to ensure the optimal combination of grass yield and nutritional content. In this study, the optimal harvest time of Secale cereale ‘Ganyin No.1’ was determined by means of assessing plant height, fresh yield, stem-leaf ratio, fresh-dry ratio, crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF), at different growth stages, in the cold region of Tianzhu. The results showed that plant height, hay yield, and ADF, and NDF content increased in correlation with growth stages. Conversely, CP content increased during the first stages, but then decreased. Growth was fastest during the jointing and heading stage. No significant difference was observed between fresh yield at flowering stage, and at milky stage (P>0.05). Though the hay yield at flowering stage was less than that at milky stage, the content of CP was highest at flowering stage with up to 2.16 t·ha-1. Applying a subordinate function analysis method, the comprehensive evaluating value during the four cutting stages decreased from heading to flowering, to booting, and to milky stage. In conclusion, the timespan from heading to flowering stage seems to be the optimal harvest time.
Effect of alfalfa-grass mix combinations on the forage productivity during the sowing year in the Horqin Sandy Land
Yong-liang Zhang, Xiu-mei Luo, Ming-hao Wu, Dong Pan
2018, 12(4): 882-890. doi: 10.11829/j.issn.1001-0629.2017-0360
[Abstract](872) [FullText HTML] (85) [PDF 512KB](82)
The legume-grass mixtures included alfalfa (Medicago sativa) and three grasses (Bromus inermis, Elymus nutans, and Phalaris arundinacea) to investigate herbage yield and plant height during the sowing year. The mixed combinations were two species mixtures at four intercropping ratios of legume:grass being 1:1, 1:2 , 2:2, and 2:1. The experiment was conducted in Tong Liao of Inner Mongolia in a randomized complete block design with three replications. The results showed that grass species had a significant influence on yield of mixed sowing of grasses (P<0.05), but did not significantly influence the yield of the mixed sowing alfalfa and legume-grass total yield (P>0.05). Ratios for the legume-grass mixture had a significant influence on yield of mixed species and total legume-grass yield (P<0.05). The greatest value of dry matter yield was obtained from alfalfa monoculture and it was significantly higher than total dry matter yield of the mixed grassland, and total yield of the legume-grass mixture was significantly higher than that of the monoculture of grass during the entire year (P<0.05). The highest total dry matter yield was obtained when alfalfa was mixed at a ratio of 1:1 intercrop with grass in the first cutting yield, and that of legume:grass at 2:1 was higher than other mixed sowing ratios in the second cutting yield and annual total yield. The total yields of the 1:2 mixture at all cutting times and annual total legume-grass yields were significantly lower than other mixed sowing combinations (P<0.05). Rates of legume-grass mixture had a significant influence on the growth of mixed grasses and the ratio of grass/legume yield. The growth of grasses was better in combinations of 1:2 and 2:2 legume-grass ratios than in other combinations and ratio of grass/legume yield reached 0.28~0.81 in annual yield. Growth of grasses was obviously inhibited in the 1:1 and 2:1 legume-grass mixed combinations and the ratio of grass/legume yield was 0.11~0.30 in annual yield.
Effect of different planting patterns on agronomic traits of silage maize
Zhen-yu Duan, Ting Wang, Zhi-qin Sang, You-de Wang, Shu-bing Chen, Bin Guo, Yu-mei Li, Xiao-wei Zhang
2018, 12(4): 891-899. doi: 10.11829/j.issn.1001-0629.2017-0335
[Abstract](792) [FullText HTML] (76) [PDF 709KB](103)
To investigate the effects of different planting patterns on agronomic characters and yield formation of silage maize, Xinsiyu 19 silage maize was selected, and there were seven different row spacing planting patterns (30+60)、(10+66)、(17+50)、(60+60)、(76+76)、(40+60) and (30+90) cm. The results showed that the plant height, ear height, and other agronomic traits, leaf area per plant, SPAD value, and dry weight per plant of the (60+60) cm planting pattern were higher than those of the other cropping patterns. With the increase in planting spacing, the light transmittance in the lower canopy of silage maize was increased. The canopy structure of silage maize is reasonable when planted in (60+60) cm, the yield of silage maize under (60+60) cm cultivation was significantly higher than that of other planting models. In different planting patterns, the agronomic traits of maize were good with the increase in row spacing, and it is conducive to the formation of silage maize production when planted in the (60+60) cm planting model.
Effect of supplementation with native grass on performance in Rex rabbits
Rong-ju Xie, Jian-ping Wang, Ning Liu, Fei-ke Zhang
2018, 12(4): 900-905. doi: 10.11829/j.issn.1001-0629.2017-0344
[Abstract](748) [FullText HTML] (68) [PDF 516KB](84)
The objective of this study was to investigate the effect of different proportions of native grass diets on late immunization index, slaughter performance, diarrhea rate, mortality rate, alkaline phosphatase (AKP) activity, and digestive organ development index in Rex rabbits. Thirty 110-days-old healthy Rex rabbits were randomly divided into three groups with 10 rabbits in each group (half male and half female). In Group Ⅰ, which was the control group, the rabbits were fed with a basal diet; Group Ⅱ rabbits were fed with 85% basal diet + 15% native grass; Group Ⅲ rabbits were fed with 70% basal diet + 30% native grass. The adaptation period was 7 days and the treatment period was 30 days. The results show that the spleen index and IgA content in the experimental Groups Ⅱ and Ⅲ were significantly higher than that in Group Ⅰ (P<0.05). There was no significant difference between the other immunological indexes (P>0.05). Compared with Group Ⅰ, the body weight and carcass weight in Group Ⅲ were increased by 11.5% and 13% (P<0.05), respectively. The AKP activity in the three experimental groups decreased with the increase in consumption of native grass (P>0.05). There were no instances of diarrhea or death in the three groups. Compared with Group Ⅰ, the duodenum ratio and jejunum ratio in Group Ⅲ were increased by 16.2% and 39.2% (P<0.05), respectively. Compared with Group Ⅰ, the caecal ratio in Group Ⅲ was decreased by 26.7% (P<0.05). In summary, rabbit harvest can be improved by improving the physical health of rabbits when they are fed with a 30% native grass diet.
Effect of supplemental level on production performance of Gansu alpine fine wool sheep
Ji-peng Jin, Chun-hui Wang, Li-ping Zhang, Xiao-yan Zhang, Chang-ji Zhang
2018, 12(4): 906-915. doi: 10.11829/j.issn.1001-0629.2017-0392
[Abstract](746) [FullText HTML] (109) [PDF 877KB](107)
To study the effects of supplemental level on the production performance of Gansu alpine fine-wool sheep in alpine pastoral areas, we selected 48 twelve-month-old reserve Gansu alpine fine-wool ewes and randomly divided them into group Ⅰ (fed pellet feed), group Ⅱ (corn and alfalfa hay), group Ⅲ (corn, alfalfa hay, and oat hay), and control group (no supplementary feeding) for winter and spring “grazing” + “feeding” tests. We compared physical indexes such as body weight, wool production, length, fineness, whiteness, strength, and elongation of sheep wool fiber. The results showed that the average daily gain in groups Ⅰ, Ⅱ, and Ⅲ was higher (148.29%, 133.09%, and 96.76%, respectively) than that in the control group. The wool production was not significantly different between the groups (P>0.05). The natural length and stretched length were significantly lower in the control group than in groups Ⅰ, Ⅱ, and Ⅲ (P<0.01). The natural length of group Ⅰ was significantly higher than that of groups Ⅱ and Ⅲ (P<0.01); the stretched length of group Ⅲ was significantly lower than that of groups Ⅰ and Ⅱ (P<0.01); and the stretched length of group Ⅱ was significantly higher than group Ⅰ (P<0.05). The maximum fineness (diameter): the fineness of group Ⅰ was significantly higher than that of the control group (P<0.01) and group Ⅱ (P<0.05). The highest level of whiteness was observed in group Ⅰ, and it was significantly higher than that of the control group (P<0.05); no significant differences were detected between the other groups (P>0.05). The strength and elongation were extremely significantly higher in the supplementary feeding group than in the control group (P<0.01); the strength of group Ⅰ was significantly higher than that of group Ⅱ (P<0.01), and the elongation of group Ⅰ was significantly higher than that of group Ⅱ (P<0.05). The feed had a significant impact on the body weight and quality of the wool. Forage nutrition deficiency is observed in winter and spring in alpine pasture areas. To meet the nutritional needs of reserve ewes and make them breed at 1.5 years of age, the feed of group Ⅰ is the best choice on the basis of grazing in the cold season.
Design of a monitoring and early warning system for snow disaster in a pastoral area of Qinghai Province
Jian-yao Fei, Xiao-dong Huang, Jin-long Gao, Tian-gang Liang
2018, 12(4): 916-923. doi: 10.11829/j.issn.1001-0629.2017-0260
[Abstract](896) [FullText HTML] (230) [PDF 885KB](101)
In this study, we aimed to improve the speed of data updating and matrix calculating capacity in a monitoring and early warning system for snow disaster by improving the means of data access and increasing application of the matrix operation. In this study, we designed a monitoring and early warning system for snow disaster in Qinghai Province using Tomcat as a Web server, GeoServer as a map server, PostgreSQL as a database, OpenLayers as map access, J2EE as a standard software, logistic linear regression for snow disaster assessment, BP-ANN as a model for livestock mortality estimation, and MATLAB for matrix calculation. We also designed a Web-page display and query for regional attribute and snow disaster information, risk probability of snow disaster, livestock mortality due to snow disaster, data import, and other functions. This system was optimized to solve the problem that a snow disaster monitoring system could not update data in sufficient time, to add the function of matrix calculus, and to reduce duplication of data operations, which are convenient for the user to manager the data of monitoring and early warning of snow disaster in pastoral areas of Qinghai Province.
Design and implementation on pasture livestock carrying capacity evaluation system based on GIS
Zhi-qiang Min, Xiao-hui Su, Bao-guo Wu, Rui-rui Yan, Li-fei Zhang
2018, 12(4): 924-932. doi: 10.11829/j.issn.1001-0629.2017-0302
[Abstract](764) [FullText HTML] (48) [PDF 1094KB](81)
Overgrazing in Northern China is a serious problem, leading to grassland resource desertification. With respect to digital rangeland management, China is still in the theoretical stage, and has not set up a sound management system to promote the use of pasture. To improve digital pasture management and rational use of grassland resources, this study estimated the carrying capacity and pasture load balance of grazing plots using the stocking model. Based on the results, a system was designed and implemented to assess the amount of pasture-based livestock. Based on the GIS development technology and the demonstration area of Tara state farm in Hulun Buir (study area), the study on the management of grassland, forecast of stocking capacity, and evaluation of livestock balance were carried out. The users of the system can estimate the land carrying capacity by the input of data related to the selection of land animals intake and grazing days. Furthermore, they can evaluate stocking balance of plots they choose. The results showed that the system can meet the demands of digital pasture management, assist Tara Rochelle state-owned farms to make decisions, and provide some significant guidance for the future research on the management of pasture management system.
Study on the management model of a grassland enterprise based on “Internet +”:A case study of the YiMu Supermarket Chain
Yuan Wu, Hui-long Lin
2018, 12(4): 933-939. doi: 10.11829/j.issn.1001-0629.2017-0241
[Abstract](978) [FullText HTML] (60) [PDF 602KB](107)
Under the background of “Internet +”, which is transforming all walks of life, the operation and management mode of grassland enterprises in this new period are undergoing profound changes. Based on this, this paper takes the example of grassland industry E-Commerce as a case。 The Yi Mu supermarket chain and analyzes its operation mode using the cost-benefit method theoretically to discuss its economic feasibility. The results show that the operational mode of the Yi Mu chain supermarkets is the “Internet + grassland industry” mode, and it can increase the profits of farmers and grassland enterprises, to achieve a win-win situation. Therefore, it is economically feasible in theory. This attempt by this grassland industry market chain is an important innovation model for “Internet + grass” in the current economic and social environment. Through in-depth discussion of the concrete application of “Internet +” in the grassland industry, we hold that the multisubject analysis and empirical analysis of the “Internet + grassland industry” model of grassland industry enterprises and the analysis of the scale of the grassland industry chain will become “Internet + grassland industry” with three key research directions in the future.