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2019 Vol.36(11)

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2019, 36(11): 1-4.
[Abstract](831) [FullText HTML] (465) [PDF 406KB](5)
Accelerating the construction of an industry and technology integration development system of an ecological safety barrier in a northern grassland
HOU Xiangyang, QI Zhi, LIANG Cunzhu, XING Qi
2019, 36(11): 2727-2732. doi: 10.11829/j.issn.1001-0629.2019-0175
[Abstract](1766) [FullText HTML] (700) [PDF 579KB](37)
The vast grassland in northern China is rich in ecological types and biodiversity. It is an important part of China’s ecological safety barrier system. It is of great significance to accelerate the construction of the ecological safety barrier in the northern grasslands to ensure national ecological security. On the basis of discussing the outstanding problems existing in the northern grassland ecosystem, this paper puts forward four construction goals of " completeness, stability, vitality and beauty” from the perspective of system integration,which have directional guiding significance for the construction of ecological security barriers in the northern grasslands;We propose that if we want to achieve the goal of building ecological barriers in the northern grassland, we must break through the key technical bottlenecks, including the technical support system for the three aspects of degraded grassland restoration, ecological grassland development, and big data driving. At the same time, we must insist on taking the direction and path of technological innovation, Industrial integration development is an effective and feasible two-pronged drive implementation path.
Effect of simulated nitrogen deposition on the community composition and stability of alpine grasslands in the Qinghai Lake Area
ZHANG Jing, DONG Shikui, ZHAO Zhenzhen, LI Shuai, HAN Yuhui, SHA Wei, SHEN Hao, LIU Shiliang, DONG Quanmin, ZHOU Huakun, Tudanjia, QI Xingmin, WANG Haoshan
2019, 36(11): 2733-2741. doi: 10.11829/j.issn.1001-0629.2019-0008
[Abstract](1813) [FullText HTML] (775) [PDF 936KB](42)
This study conducted a test that doubled nitrogen contents [0, 8, 24, 40, 56, 72 kg·(hm2·a)–1] by applying NH4NO3 to investigate the effects of nitrogen deposition on community composition and the stability of alpine grasslands in the Qinghai Lake Area. After two years of continuous nitrogen application, the results showed that the important values of different functional groups responded differently to nitrogen additions. The responses of the Gramineae and forbs function groups were considerably, but no obvious variation was observed in the important values of the Cyperaceae and Leguminosae function groups. In Gramineae, the 72 kg·(hm2·a)–1 addition has a significantly higher important value than the treatment of 8 kg·(hm2·a)–1, whereas the important value of forbs reduces significantly. With the increase of nitrogen application contents, Poa pratensis was the most dominant species within the entire plant community. Compared with the plant communities without nitrogen additions, the Patrick richness and Pielou evenness values of the plant community were decreased but were not significant with the treatment of 72 kg·(hm2·a)–1; the Shannon-Wiener diversity was significantly reduced, and the other treatments can promote the species diversity of the plant community to a certain degree. There was a significant negative correlation between the community stability and the Shannon-Wiener diversity and Pielou evenness under different nitrogen treatments. Therefore, short-term nitrogen additions will change the species compositions of plant communities in alpine grasslands, and the effect of high nitrogen on species diversity is obvious. This dynamic can affect the stability of Qinghai’s alpine grassland community.
An analysis of fractional vegetation cover of the Gannan grassland in the non-growing season based on Multispectral data and small UVAs
LENG Ruolin, ZHANG Yaoyao, XIE Jianquan, LI Funing, XU Gang, CUI Xia
2019, 36(11): 2742-2751. doi: 10.11829/j.issn.1001-0629.2019-0013
[Abstract](1419) [PDF 783KB](39)
Vegetation from non-growing seasons is a vital animal feed type for livestock in winter and spring. Therefore, estimates of the livestock carrying capacity of local ranches are important for studying non-growing season vegetation. In this paper, Gannan prefecture was taken as the research area, and 60 m × 60 m digital photos of non-growing season vegetation of the prefecture’s grasslands were obtained via cameras mounted on small unmanned aerial vehicles (UVAs). The non-growing season vegetation coverage was obtained by a supervision classification from digital photos. Using the MODIS/Terra + Aqua bidirectional reflection distribution function and the hemispheric reflectivity product of MCD43A4 together with the Landsat8 OLI image data, the soil tillage index (STI), dead fuel index (DFI), and normalized difference tillage index (NDTI) a total of 9 vegetation indexes were calculated. By analyzing the correlations between different vegetation indexes and fractional vegetation cover (FVC), a regression model of grassland FVC in the non-growing season was established; then, the accuracy of model was evaluated to compare the ability of different data sources that can most accurately estimate the FVC. The results show that: 1) Landsat8 OLI data is more suitable than MODIS data for studying FVC during the non-growing season in the Gannan grasslands; 2) NDTI is the best index for non-growing season FVC estimations in the study area, and its linear estimation model of y = 1 432.074x – 166.855 (R2 = 0.407) is the optimal inversion model of FVC in the non-growing season; 3) From April to May in 2018, Gannan has a high FVC in the west and a low FVC in the east; coverage rates in most regions ranges from 20% to 50%, with only the rates in the north part of Xiahe, the central part of Hezuo and the southeast part of Maqu being less than 20%. The coverage rate in the northeast part of Maqu is over 60%. This study can provide a basis for calculating the seasonal livestock carrying capacity in Gannan prefecture.
The correlation and niche of survival community of Kengyilia thoroldiana in Maduo County, Qinghai Province
ZHANG Jing, Caiwendaiji, Suonancairen, WEN Xiaocheng, WANG Shengcai, YANG Maoji, Renzengouzhu, SUN Haiqun
2019, 36(11): 2752-2765. doi: 10.11829/j.issn.1001-0629.2019-0310
[Abstract](1202) [PDF 598KB](29)
The soil concentration gradients of 12 common plant species and 66 species pairs from Maduo County, Qinghai Province were determined using χ2 tests, correlation analysis, niche breadths, and niche overlaps in order investigate the correlations between niches and species and to further our understanding of the ecology of the rare Kengyilia thoroldiana plant. The results showed that: 1) The common characteristics of common species in the community were not significantly negatively correlated and were independent of each other. The positive-negative correlation ratios found in the χ2 test, Pearson’s correlation coefficient test, and Spearman’s rank correlation coefficient test (1.06, 1.10, and 0.97, respectively) were roughly equal to one. Therefore, the community may be in a relatively stable transitional stage in terms of vegetation succession. 2) There were no significant relationships between K. thoroldiana and other common plants. The Spearman’s rank correlation coefficients showed insignificant positive correlations with five plants, such as Poa annua, and insignificant negative correlations with six plants, such as Leontopodium leontopodioides. 3) K. thoroldiana showed wide niche breadth and large niche overlap under the six soil factor gradients, and had strong ecological adaptability and a competitive advantage. 4) Among the 66 species pairs, the pairs with stronger positive correlations showed relatively large niche overlap in every soil factor gradient. Nevertheless, the pairs with stronger negative correlations showed niche overlap only in certain soil factor gradients and did not possess as strong positive correlations in terms of overall overlap. In the future, human damage to K. thoroldiana populations should be reduced in order to ensure the natural succession of the community and to ensure the sustainability of the genus’ germplasm resources.
Effects of short-term enclosure on the vegetation characteristics of a lightly degraded alpine meadow in Guinan County
JIA Zhifeng, MA Xiang, XU Chengti, LIU Wenhui, WEI Xiaoxing, LEI Shengchun
2019, 36(11): 2766-2774. doi: 10.11829/j.issn.1001-0629.2019-0151
[Abstract](1437) [FullText HTML] (660) [PDF 757KB](32)
Grassland degradation has seriously affected the development of animal husbandry on the Qinghai-Tibetan plateau. To clarify the influence of short-term enclosure on the vegetation characteristics of alpine meadows, the short-term enclosure of a lightly degraded alpine meadow was conducted. The vegetation coverage, vegetation height, functional groups (grass, sedge, and forb), and annual dynamic change characteristics of the biomass inside and outside the fence were studied, to provide a scientific basis for the management of alpine meadows. The results showed that short-term enclosure could significantly improve the coverage, height, and aboveground biomass of a lightly degraded alpine meadow. In addition, the response of different plants to grazing exclusion was different. Grasses and forbs grew rapidly from July to August, while sedges gradually increased after September. In 2012, the sedge biomass accounted for over 60% of the total biomass on the ground, the grass biomass accounted for approximately 30%, and the forbs biomass was below 10%. Moreover, the grass, sedge, and total biomass in 2012 were higher than those in 2011. The average aboveground biomass increased by 12.4%, 161.5%, and 52.8% in July, August, and September, respectively, and the forbs biomass decreased by 57.1%. In summary, short-term enclosure can be used for the restoration and management of lightly degraded alpine meadows in Guinan County.
Nitrous oxide release from grassland driven by livestock excreta and its influencing factors
NING Ruidi, SONG Yueqing, WANG Ling
2019, 36(11): 2775-2785. doi: 10.11829/j.issn.1001-0629.2019-0156
[Abstract](1537) [FullText HTML] (647) [PDF 575KB](15)
Livestock excreta represent a major source of nitrous oxide (N2O), the emission of which makes a significant contribution to the greenhouse effect. In this review, based on available knowledge, we summarize the N2O release process driven by livestock excreta and the associated driving factors. The input of livestock excreta to the soil results in changes in the microbial processes of nitrification and denitrification, and denitrification of nitrifying bacteria, thereby regulating the production and release of N2O. These processes can be affected by the type of excreta, soil physicochemical properties, and plant characteristics. On the basis of current research, we propose suggestions for the focus and direction of further research on N2O emissions.
Changes in phenology in the Tibetan Plateau under climate change
HAN Binghong, KONG Xiangping, ZHOU Bingrong, SHI Mingming, ZHAO Henghe, NIU Decao, FU Hua
2019, 36(11): 2786-2795. doi: 10.11829/j.issn.1001-0629.2019-0112
[Abstract](1962) [FullText HTML] (836) [PDF 786KB](41)
Phenology is expected to be one of the most sensitive and easily observable natural indicators of climate change. Accelerated warming of the Tibetan Plateau (TP) since the mid-1980s has resulted in significant environmental changes. These new conditions are accompanied by phenological changes that are characterized by considerable spatiotemporal heterogeneity. The impacts of climate change and human activity on phenology were significant in the Qinghai-Tibetan Plateau; accelerated warming and optimal grazing advanced the timings of green-up and flowering but it delayed the end date of senescence. However, the timing of fruiting was relatively stable compared with that of the other phenophases. These changes were mainly caused by changes in temperature, moisture, and grazing. Warming and excessive rainfall and moderate grazing contributed to advanced and long phenophases, whereas warming and drought led to delayed and shortened phenophases. The changes in phenophases had significant influences on the structure and function of population, community, and ecosystem. However, currently, there are few studies on phenology, especially effects of changes in phenology on the structure and function of the ecosystem of the Tibetan plateau. Therefore, we need to pay more attention to effects of climate change on alpine plant phenological response from the physiological-level to ecosystem-level and to the feedback of phenology on the structure and function of ecosystems in the future.
Effects of the conversion of cropland to grassland on soil microbial and nematode communities in the Danjiangkou water source conservation area
ZHOU Guangfan, YANG Dianlin, QIN Jie, LI Qingmei, ZHAO Jianning
2019, 36(11): 2796-2805. doi: 10.11829/j.issn.1001-0629.2019-0073
[Abstract](883) [PDF 608KB](13)
Studying the changes in characteristics and mechanisms of interaction between the soil microbial and nematode communities resulting from the conversion of cropland to grassland in the Danjiangkou water conservation area can provide primary data for comprehensive analysis and evaluation of the ecological effect of soil. Additionally, this can offer a scientific basis for the regional ecological environmental protection and sustainable land use. In September 2017, we chose three representative Alfalfa (Medicago sativa) grasslands (three years) for the conversion of cropland to grassland. The plots are located upstream of the Danjiangkou water conservation area. We also chose an uncultivated maize (Zea mays) field as the control. In this study, we examined the effects of the conversion of farmland to grassland on the microbial organisms present in the soil and the interactions between the soil microbial and nematode communities. The results showed that the soil microbial community structure changed greatly after the cropland was converted into grassland in the Danjiangkou water source conservation area. The amount of total microbial phospholipid fatty acids in the 0 – 10 and 10 – 20 cm soil layers increased significantly by 59.13% and 62.58%, respectively (P < 0.05). The soil organic carbon, total nitrogen, and nitrate nitrogen contents had a positive correlation with the total phospholipid fatty acids (PLFAs) (P < 0.01), whereas, the soil pH and C/N negatively correlated with the total PLFAs (P < 0.05). As the main components of the soil micro-food web, there is an interaction between the nematodes and the microbial community. The soil G bacteria had a negative relationship with the abundance of bacterivores (P < 0.05), and a positive correlation with the abundance of fungivores (P < 0.05). Moreover, a significant positive correlation was observed between the G bacteria and nematode ecological index (EI and SI) (P < 0.05). This study indicated that the conversion of cropland to grassland changed the micro-food web structure, and soil nematode contributed more to the stability of the soil micro-food web.
Comparison of salt tolerance during the germination period of 12 grass species under severe salt stress
LIU Lu, ZHANG Yuequn, WANG Jing, GU Weibing, ZHANG Jianquan, LIU Qihua, WANG Huihui, ZHANG Xinxin, CHAI Qi
2019, 36(11): 2806-2819. doi: 10.11829/j.issn.1001-0629.2019-0002
[Abstract](1697) [FullText HTML] (797) [PDF 569KB](25)
In order to screen grass species suitable for planting in coastal areas characterized by saline soils, we selected a range of grasses, including Poa pratensis, Festuca arundinacea, and Lolium perennia, as materials to determine their germination indices, growth dynamics, and root systems under salt stress induced by 300 mmol·L–1 NaCl and 50 mmol·L–1 MgSO4 salt solutions applied via moistened filter paper. The results revealed that the two species L. perenne and F. arundinacea had the highest salt tolerance. Although the reduction in grass germination under salt stress was no higher than 20% and the effects were non-significant, the suppression of shoot and root growth was greater than 50% compared with that of control plants (P < 0.05). Total root system length, total root system areas, and lateral root number were all reduced by more than 50%. For Agrostis and Trifolium, the reduction in the average diameter of the root system in response to salt stress was between 0% and 100%. Three species with higher salt tolerance were L. perenne, F. arundinacea, and F. sinensis. Amongst the L. perenne varieties, γ, Gentry, and Barlennium showed higher salt tolerance, whereas among Festuca spp., the cultivars Fire Phoenix2, BarvadoⅡ, and Naihan showed higher salt tolerance. Similarly, among Trifolium spp., cultivars with salt tolerance were Super-Huia in T. repens, Dolly in T. pratense, and Cherry in T. incarnatum. Furthermore, among Poa pratensis varieties, those with a higher salt tolerance were Merit, Baron, and Blue Chip, whereas among Agrostis spp., the cultivars A-1, Kromi BT, Impala, and Highland all had higher salt tolerance.
Seed dormancy and germination characteristics of several species of the Caragana genus
YUAN Zhen, CHEN Dali, LUO Xinping, YANG Lingjie, HU Xiaowen
2019, 36(11): 2820-2830. doi: 10.11829/j.issn.1001-0629.2019-0152
[Abstract](1573) [FullText HTML] (763) [PDF 815KB](26)
The majority of legumes in the temperate zone have water-impermeable seeds; however, little is known about seed dormancy and the response of seed germination to environmental factors, such as temperature and water potential. Thus, the seed dormancy and germination in response to temperature and water potential in 15 Caragana species were studied. The results showed that: 1) the percentage of hard seeds in Caragana roborovskyi and C. acanthophylla was 63% and 14%, respectively, while this was lower than 10% or absent in the other species. 2) Dry storage significantly decreased the percentage of hard seeds of the tested species to various degrees (P < 0.05). For example, the hard seed percentage of C. roborovskyi decreased from 63% to 37%. 3) With an increase in temperature, the germination percentage and germination index increased and then decreased. The germination range and temperature threshold varied according to the species. 4) The germination percentage and germination index of all species decreased with a decrease in water potential, while their sensitivity to water stress varied according to the species. Thus, the seeds of most Caragana species were permeable to water, and dry storage at room conditions significantly decreased the number of hard seeds, which should be considered during future studies.
Effect of different ratio of red and blue light emitting diodes on growth and physiological characteristics of two cool-season turfgrass
CHEN Dijie, HAN Liebao, SONG Guilong, CHEN Yufeng
2019, 36(11): 2831-2837. doi: 10.11829/j.issn.1001-0629.2018-0628
[Abstract](2229) [FullText HTML] (739) [PDF 862KB](26)
To solve the problem posed by shade in stadium, the objective of this study was to investigate the effect of the correct red/blue light emitting diodes (LED) light ratio on the of two cool-season turfgrasses (Lolium perenne ‘Monterey No.3’ and Festuca arundinacea ‘Crown’). The amount of catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD), malondialdehyde (MDA), and hydrogen peroxide (H2O2), and membrane penetrability, tiller, and growth rate of the turfgrasses were measured. A completed randomized block design was adopted in this study, which included four red/blue light ratio treatments: 3∶1, 5∶1, 7∶1, and 9∶1. The results of this study indicate that turfgrasses planted under 3∶1 and 9∶1 treatments showed worse growth and physiological characteristics, which means excessive blue or red spectrum caused significant damage to turfgrasses. The 7∶1 ratio treatment showed the lowest stress as CAT and APX were more activated and the number of tiller and the growth rate were higher than those in other treatments. In addition, the content of MDA and H2O2 and the membrane penetrability were lower compared to those in other treatments, and turfgrass were healthier in general in the 7∶1 treatment.
Effect of grass planting on soil nitrogen transformation and dissolved nitrogen concentration of urban greening lands
WANG Qin, FU Xinlei, TAO Xiao, XU Xiaoniu
2019, 36(11): 2838-2846. doi: 10.11829/j.issn.1001-0629.2019-0313
[Abstract](1435) [FullText HTML] (665) [PDF 541KB](24)
Nitrogen (N) transformation is an important ecological process for the maintenance of soil N availability. To determine the effect of grass planting on soil nitrogen transformation, potential N mineralization was measured for the surface 0–30 cm soil layer from different greening lands in the campus of Anhui Agricultural University and Hefei Huancheng Park, using a laboratory incubation method. A comparative analysis of dissolved N (DN) concentrations between different greening land types was performed. The results showed that soil bulk density was significantly decreased by grass planting. Grass planting had a significant effect on soil inorganic N, but had no significant effect on soil moisture, total N, or DN. The mean net N mineralization potential was 85.99 μg·(kg·d)–1 in greening lands with grass planting, which was 15.6% higher than in greening lands without grass planting. Grass planting significantly increased net ammonification potential, whereas it had no effect on net nitrification potential. Our findings indicated that the characteristics of soil N transformation in urban soils were changed by grass planting, with significantly enhanced N ammonification. This may help improve N availability and decrease N loss in urban soils.
Effects of exogenous 5 – aminolevulinic acid on physiological characteristics of alfalfa
LI Dandan, LIANG Zongsuo, YANG Zongqi, HAN Ruilian
2019, 36(11): 2847-2853. doi: 10.11829/j.issn.1001-0629.2019-0159
[Abstract](1325) [PDF 816KB](16)
This study was conducted to determine the effect of different concentrations (0, 5, 10, 15, 20, 25 mg·L–1) of exogenous ALA (5 – aminolevulinic acid) on the antioxidant system and on photosynthesis in alfalfa (Medicago sativa). The results showed that foliar application of 10 mg·L–1 ALA could significantly increase the photosynthetic pigment content of alfalfa seedlings (P < 0.05). In addition compared to the control, the chlorophyll a, chlorophyll b, carotenoids, and total chlorophyll contents in the leaves of " Nongmu 806” seedlings increased by 12.29%, 36.21%, 18.69%, and 11.46%, respectively. Finally, exogenous 10 mg·L–1 ALA caused significant increases in the activities of various antioxidant enzymes (SOD, POD, CAT, APX) and in soluble protein (SP) content, but reduced the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS). These results indicate that the application of moderate amounts of ALA could increase the accumulation of photosynthetic pigments and could augment the activities of antioxidant enzymes in the leaves of alfalfa seedlings.
Effect of arbuscular mycorrhizal fungi on alfalfa seedling growth at different soil pH
DENG Jie, LI Fang, GU Lijun, DUAN Tingyu
2019, 36(11): 2854-2862. doi: 10.11829/j.issn.1001-0629.2019-0083
[Abstract](1408) [FullText HTML] (642) [PDF 756KB](22)
The present study was performed in a greenhouse to test the effects of arbuscular mycorrhizal fungi (AMF) on the growth of Medicago sativa (alfalfa) in the seedling stage under different soil pH. The plants were inoculated with Claroideoglomus etunicatum, Rhizophagus intraradices along with the mixture of two AMF fungi at three different soil pH values (6.48, 5.0, and 3.0). The results showed that with the reduction of soil pH, the plant height, leaf number, chlorophyll content, net photosynthetic rate, phosphorus absorption, and biomass of alfalfa were significantly reduced, whereas malondialdehyde (MDA) concentration was significantly increased. The presence of AMF alleviated the damage caused by acid stress on the plants. Compared to NM treatment, inoculation with AMF promoted plant growth, phosphorus absorption, and photosynthesis. Moreover, alfalfa colonized by AMF had a higher value of superoxide dismutase (SOD) enzyme activity and biomass, and a lower MDA concentration. The mixture of C. etunicatum and R. intraradices had the most significant positive effects on plant growth. The plant height, leaf number, chlorophyll content, net photosynthetic rate, total phosphorus content, and biomass of alfalfa were increased by 195.53%, 332.57%, 89.65%, 167.42%, 915.01%, and 97.7% (P < 0.05), respectively. In addition, the activity of SOD increased by 137.11% (P < 0.05) and the concentration of malondialdehyde (MDA) decreased by 47.15% (P < 0.05).
Variation characteristics of nutrient contents in a 5-year Medicago sativa and Poa pratensis rotation
A Yun, SHI Shangli, ZHANG Xiaoyan, ZHANG Cuimei, LI Wen, WU Fang, ZHOU Tong, LAI Xingliang, CHEN Yonggang, SUN Shoujiang
2019, 36(11): 2863-2870. doi: 10.11829/j.issn.1001-0629.2018-0711
[Abstract](1469) [FullText HTML] (690) [PDF 946KB](17)
Alfalfa crop rotation is a high-level planting method that is beneficial for the balanced use of soil nutrients and the prevention of diseases, insects and grass damage. In this paper, we investigated the variation of soil nutrients in a 5-year Medicago sativa ‘Gannong No.9’ →Poa pratensis ‘Haibo’ rotation, with continuous cropping of alfalfa used as control. Samples we collected at a soil depth of 0 – 20 cm and 20 – 40 cm soil every three months, as well as in April, July and October in the 1 – 2 years after crop rotation. Organic matter, total nitrogen, available nitrogen, total phosphorus and total potassium content was measured. The results showed that the content of soil organic matter, total nitrogen, available nitrogen, total phosphorus and total potassium in the first year after rotation was higher than that in the second year. In the first year after rotation, the nutrition indices of soil organic matter, total nitrogen, available nitrogen, total phosphorus and total potassium increased by16.32%、6.16%、4.13%、17.94% and 8.29%, respectively, in the 0 – 20 cm layer, and increased by 30.69%、5.00%、2.29%、3.33% and 30.00%, respectively, in the 20 – 40 cm soil layer . In the second year after rotation, these nutrition indices increased by 9.45%, 5.14%, 3.54%, 24.49% and 19.37%, respectively, in the 0 – 20 cm layer, and increased by 16.70%、0.97%、4.89%、25.00% and 26.48%, respectively, in the 20 – 40 cm soil layer. The content of soil organic matter, total phosphorus and total potassium in alfalfa to Poa pratensis rotation was significantly higher than that of continuous alfalfacropping, while the content of total nitrogen and available nitrogen in rotation soil had little difference with that of continuous cropping. In summary, alfalfa-Poa pratensis rotation improves organic matter, total phosphorus and total potassium content, and the utilization of nitrogen.
Research progress on the molecular biology of Lotus corniculatus
LI Zongying, WANG Dan, BIAN Jiahui, SUN Zhanmin, FU Hua, LYU Jiawei, WU Yanmin
2019, 36(11): 2871-2886. doi: 10.11829/j.issn.1001-0629.2019-0100
[Abstract](3949) [FullText HTML] (868) [PDF 679KB](25)
Lotus corniculatus is a perennial leguminous forage of excellent quality. It is rich in nutrition, with good adaptability and strong ecological adaptability. It can be widely used in applications such as livestock breeding, garden afforesting, and soil restoration. Furthermore, L. corniculatus can be used in herbal medicine preparations to treat human diseases. In order to expand the application of L. corniculatus in production practice, many in-depth research studies have been performed domestically and internationally. This paper focuses on the current research progress in seven research fields, including genetic diversity and phylogenetic analysis, stress and herbicide resistance, nodule nitrogen fixation, condensed tannins, bioreactors, and pharmacological applications. The shortcomings and prospects of the application of L. corniculatus are discussed.
Protective effects of exogenous ABA on oxidative damage in maize seedlings under drought stress
WANG Fang, WANG Tiebing, LI Pengde
2019, 36(11): 2887-2894. doi: 10.11829/j.issn.1001-0629.2018-0631
[Abstract](1390) [FullText HTML] (610) [PDF 685KB](18)
Pot experiments were conducted to study the effects of different concentrations of abscisic acid (ABA) on the growth of maize seedlings under moderate drought stress (15% Polyethylene glycol). The experimental results showed that drought stress considerably inhibited the growth of maize seedlings compared with the control. The activities of catlase (CAT), superoxide dismutase (SOD) and peroxidase (POD) decreased by 65.56%, 51.27%, and 39.05%, respectively, Malondialdehyde (MDA) content increased by 85.06%, and soluble sugar, soluble protein and chlorophyll contents decreased by 55.91%, 54.80%, and 43.08%, respectively. Appropriate concentrations of exogenous ABA effectively alleviated drought stress on maize seedling growth, inhibited an increase of MDA content in maize seedlings caused by drought stress, increased the activity rates of SOD, POD and CAT, inhibited the decrease of chlorophyll, and prevented a decrease of soluble sugar and soluble protein contents in the drought-stressed maize seedlings. The results showed that these effects of ABA have an obvious dosage effect. A 15 μmol·L–1 ABA treatment can alleviate the inhibitory effect of drought stress on maize seedlings. Compared with the drought stress, the activities of CAT, SOD and POD in maize seedlings increased by 73.91%, 69.79% and 50.69%, respectively; MDA content decreased by 40.63%, while soluble sugar, soluble protein and chlorophyll contents increased by 79.75%, 57.81% and 44.24%, respectively. Therefore, the exogenous ABA treatment of 15 μmol·L–1 can improve the activity of protective enzymes and drought tolerance of maize seedlings.
Investigation of soil insect pest species, damage and resistance in alfalfa
SHI Min, CAO Shi, HU Jinling, DANG Shuzhong, LI Yanzhong
2019, 36(11): 2895-2906. doi: 10.11829/j.issn.1001-0629.2018-0654
[Abstract](1934) [FullText HTML] (664) [PDF 756KB](26)
In order to select resistant varieties that can be recommended for use in alfalfa production, resistance of 44 varieties in Hohhot were evaluated, soil insect species were identified, damage of alfalfa roots by soil insects was determined, and percentage of injured plants were investigated in this study. The results showed that soil insect pests in this site were Maladera orientalis, Anomala mongolica, Selatosomus gravidus, Gonocephalum reticulatum and Opatrum subaratum, which accounted for 27.56% of total soil insect number. Insects inflicted plant injury by chewing root cortexes or boring root steles. The damage rate in plants was 1.19 to 28.85% (average 2.77%). All alfalfa varieties were highly resistant based on the National Alfalfa and Forage Alliance (NAFA) in the United States of America. Nevertheless, relative resistance existed between varieties. Based on analysis with a clustering method, the 44 varieties were divided into six groups: 10 varieties (22.64% of total varieties) were high resistance (HR) varieties, including Xinmu No. 2, MF4030, Hunter River and MF4010; 10 were resistance (R) varieties (29.54%), including Zhongcao No. 3, Zhaodong and Magnum; 13 were moderate resistance (M) varieties (22.73%), including Aohan and SK3010; 9 were low resistance (L) varieties (20.45%), including Nongmu 806, Zhungeer and Giant; and 2 were susceptible (S) varieties (4.55%), Rambler and Dryland.
Common vetch hay and the influence of Yucao on the digestibility, metabolism, and greenhouse gas emissions of lambs
PAN Yueting, WANG Chunmei, ZHANG Cheng, TANG Qilin, HOU Fujiang, NAN Zhibiao
2019, 36(11): 2907-2914. doi: 10.11829/j.issn.1001-0629.2019-0042
[Abstract](2233) [FullText HTML] (722) [PDF 809KB](30)
To study the effects of common vetch (Vicia sativa) and Yucao on the digestion and metabolism of livestock, 6-month-old hybrid rams were fed one of the following three diets: diet 1, 100% Yucao; diet 2, 30% V. sativa and 70% Yucao; diet 3, 45% V. sativa and 55% Yucao. Results showed that 1) dry matter intake and the digestibility of Diet 3 were higher than Diet 1 and Diet 2; 2) the neutral detergent fiber and crude protein digestibility of Diet 3 were significantly higher than Diet 1 and Diet 2 (P < 0.05); and 3) a mixed diet of V. sativa and Yucao reduced greenhouse gas emissions, which were the lowest in Diet 2. However, there was no significant difference in oxygen consumption, methane emissions, or carbon dioxide emissions per unit of dry matter intake between Diet 2 and Diet 3. Based on the above results, a diet of 45% V. sativa + 55% Yucao will increase feed digestion and metabolism by lambs and at the same time, can be used as an effective greenhouse gas emission reduction measure in animal husbandry.
Linking density of plateau pika to vegetation characteristics and soil attributes in response to different grazing regimes
FENG Feng, GONG Baocao, NIU Kechang
2019, 36(11): 2915-2925. doi: 10.11829/j.issn.1001-0629.2019-0136
[Abstract](1309) [FullText HTML] (674) [PDF 881KB](47)
With changes in climate conditions and land use, the increase in the density of plateau pika (Ochotona curzoniae) challenges the sustainable management of alpine rangelands on the Qinghai-Tibet Plateau. Plateau pikas can affect grassland vegetation and soil properties. However, there is a lack of knowledge about the associations between plateau pika, vegetation, and soil in response to different grazing regimes (e.g. single-household vs. multi-household pastures). In this study, we worked at three sites in the alpine rangelands on the eastern Qinghai-Tibet Plateau to compare the density of plateau pika burrows, vegetation characteristics, soil properties, and their associations with single-household versus multi-household pastures. Compared to those of single-household pastures, the multi-household pastures were characterized by lower density of plateau pika burrows and less soil nutrients but taller vegetation. There were nonsignificant differences in vegetation cover, plant species richness, soil organic matter, soil pH, and humidity between single-household and multi-household pastures (P > 0.05). In single- and multi-household pastures and overall sites, the density of plateau pika burrows significantly negatively correlated with the vegetation height and plant species richness (P < 0.05), but positively correlated with soil pH and available nitrogen. In sum, multi-household grazing potentially depresses the outbreak of plateau pika by increasing vegetation height and plant diversity.
Effects of dietary roughage sources on the rumen microflora and muscle fatty acids in finishing Hu lambs
DONG Chunxiao, LYU Jiaying, NIU Xiaolin, MA Wanhao, LI Fei, LI Fadi
2019, 36(11): 2926-2936. doi: 10.11829/j.issn.1001-0629.2019-0092
[Abstract](941) [PDF 548KB](33)
The objective of the present study was to evaluate the effects of dietary roughage sources on the rumen microflora and muscle fatty acids in finishing Hu lambs. According to the principle of similar weight, 120 male Hu lambs (22.9 ± 1.2 kg) of age 60 days were randomly divided into four groups (each comprising of five fences of six lambs). Four dietary roughage sources of corn stalk (CS), corn cob (CC), sunflower seed hull (SH) and rapeseed straw (RS) were fed to the four groups. For all the four groups, the proportion of roughage was 20%, and the ingredient concentration was the same. The period of the pre-test was seven days, while the period of the formal test was 70 days. At the end of the trial period, from each fence, three sheep of average weight were selected for slaughter. The rumen fermentation, rumen flora structure, and muscle fatty acid-related indicators were determined. The results showed that: 1) the ratio of valerate and isovalerate in the rumen of the SH and RS groups was significantly higher than that of the CS and CC groups (P < 0.05). The proportion of acetate in the CC group was significantly higher than that in the CS and the RS groups (P < 0.05). 2) The abundance and diversity of the rumen bacterial community in the RS group were the highest, and the similarity of the rumen flora among each group was low. Firmicutes, Bacteroidetes, Spirochaetaes, and Fibrobacteres were the dominant bacteria in the rumen of all the four groups of sheep. The relative abundance of Firmicutes in the RS group was significantly higher than that in the CC group (P < 0.05). The relative abundance of the Spirochaetae in the CC group was significantly higher than that in the SH and RS groups (P < 0.05). The relative abundance of Fibrobacteres in the RS group was significantly lower than the other three groups (P < 0.05). 3) The content of polyunsaturated fatty acids in the SH group was significantly higher than that in the CS group (P < 0.05), and the difference between the other groups was not significant (P > 0.05). The results showed that corn cob diet changes the rumen fermentation process of lambs and increases the proportion of acetate in the rumen. This is beneficial for the proliferation of cellulolytic bacteria and is also suitable as a source of roughage for Hu sheep.
Effect of grazing on insect communities in grassland ecosystems: Research status and progress
YANG Xingzhuo, YUAN Minglong
2019, 36(11): 2937-2951. doi: 10.11829/j.issn.1001-0629.2018-0040
[Abstract](1429) [FullText HTML] (711) [PDF 1417KB](39)
Grazing is not only the main use type of natural grasslands, but it also constitutes a basic measure of grassland management. Insects are important components of biodiversity in grassland ecosystems. However, studies on the effects of grazing on insect diversity are limited. We retrieved all studies on insect diversity with grazing published in the past 40 years from two literature retrieval platforms, i.e., Web of Science and China National Knowledge Infrastructure. We summarized all results of these studies, analyzed the change trends of insect diversity under different grazing conditions and discussed how grazing affects insect diversity. Finally, we suggested the promising research directions in grassland entomology with grazing by considering the paucity of present studies on grazing and insect diversity.
Anticoagulant resistance evaluation in plateau zokor (Eospalax baileyi) based on Vkorc1 gene variation in eastern Qinghai-Tibetan Plateau
TAN Yuchen, HAN Tianhu, XU Guocheng, WEI Yanming, CAI Zhiyuan, WANG Chan, YAO Baohui, GUO Huailiang, SU Junhu
2019, 36(11): 2952-2961. doi: 10.11829/j.issn.1001-0629.2019-0007
[Abstract](2060) [FullText HTML] (728) [PDF 991KB](21)
Rodent resistance to coagulant drugs is usually associated with vitamin K epoxide reductase complex subunit 1 (Vkorc1) genetic variation. In this study, we analyzed nucleotide variation of three exons of the Vkorc1 gene in the plateau zokor (Eospalax baileyi) in eight regions of the eastern margin of the Qinghai-Tibet Plateau, through sequencing to identify genotypes and analysis of drug resistance in association with known mutations. For results, the three exons of the Vkorc1 gene of the plateau zokor were successfully obtained through PCR, and the presence of polymorphism was detected. Among the 870 plateau zokor individuals, 197 individuals had different Vkorc1 amino acid sequences from the wild type sequence. Geographically, Vkorc1 gene mutations were detected in five populations, and four genotypes were defined. Four missense mutation sites in Vkorc1 amino acid of plateau zokors were detected. Phe63Cys amino acid mutations were detected in four plateau zokor populations. When comparing the amino acid sequences with Rattus norvegicus, 18 missense mutations were found in the Vkorc1 gene of plateau zokor. This study provides a basis for the geographic management of resistant zokor populations and the control of resistance in the eastern margin of the Qinghai Tibetan plateau.
The ecological role of and survival threats to grassland rodents
ZHENG Qiaoyan, TANG Zhongmin, WEI Wanrong
2019, 36(11): 2962-2970. doi: 10.11829/j.issn.1001-0629.2019-0244
[Abstract](1938) [FullText HTML] (873) [PDF 629KB](25)
Grassland rodents are an indispensable part of grassland ecosystems and play an important role in maintaining and optimizing the function of grassland ecosystems. However, these rodents are threatened by the grassland management departments that often focus on the negative effects of grassland rodents and ignore or seriously underestimate the ecological role that they play. Therefore, this paper describes the key grassland rodent species and their ecological role in grassland ecosystem engineering, and summarizes the threats that they are currently facing (including the effect of habitat loss, population killing, disease and alien species invasion and climate change), thus providing a reference for grassland rodent management and protection.
A study on total factor productivity of China’s forage industry
SHI Zizhong, WANG Mingli
2019, 36(11): 2971-2979. doi: 10.11829/j.issn.1001-0629.2018-0665
[Abstract](1293) [FullText HTML] (750) [PDF 628KB](28)
Based on a micro-survey and unbalanced panel data from China’s alfalfa, silage corn, and ryegrass production from 2011 to 2017, the Malmquist index and a stochastic frontier analysis model were used in this study to analyze the total factor productivity of China’s forage industry and the factors responsible for its variation. The results showed that the total factor productivity of alfalfa production declined by an average of 2.32% per year from 2011 to 2017, while that of silage corn and ryegrass increased by an average of 8.91% and 0.33% per year, respectively. The main factors inhibiting the improvement of the total factor productivity of China’s forage industry were that the technology and equipment used for forage production were backward, operators’ production concepts and management technologies were not implemented, the national policy support system for the forage industry was imperfect, and producers are facing higher production and market risks. Finally, some suggestions were put forward, including promoting technology research and development, popularizing the forage industry, intensifying training systems, and perfecting the policy support system.
Analysis of microbial populations in alfalfa silage and screening and identification of the main strains
MA Zhaowen, LI Yuanxiao, LIANG Han, WANG Zhanbin, LI Wang
2019, 36(11): 2980-2988. doi: 10.11829/j.issn.1001-0629.2019-0006
[Abstract](2666) [PDF 1151KB](12)
Alfalfa is the most important source of roughage protein for ruminants. It has its optimal feed value when used as silage. The purpose of this study was to analyze the main microbial composition of alfalfa silage, to screen the main strains of alfalfa silage on this basis, and to develop microbial additives suitable for alfalfa silage. Firstly, the microbial population and community composition in natural semi-dry alfalfa silage were analyzed by macrogenomic sequencing. Based on this analysis, MRS, NA, LB, PDA and Mai's media were used to screen microbial species from natural alfalfa silage fodder, under both aerobic and anaerobic culture conditions. The species and genera of the screened microorganisms were identified by morphological and molecular biological methods. The results showed that the main microbial communities (identified at the genus level) in alfalfa silage were Oceanobacillus, Lactobacillus, and Bacillus, which accounted for 24.9%, 14.3%, and 13.9% of the detected microorganisms, respectively. A total of 30 strains were isolated on different media, under aerobic and anaerobic conditions, at 37 ℃. After morphological analysis and conservative sequence alignment, 15 strains were identified as L. plantarum; 8 strains were identified as B. subtilis; 2 strains were identified as B. licheniformis; and 1 each was identified as Pediococcus acidilactici, Enterococcus faecium, B. aryabhattai, B. pumilus and B. amyloliquefaciens. The selected strains and their identification results were consistent with the results of macrogenomic sequencing analysis, indicating the reliability of these results.
GIS-based study on the partition of different ecological-functional areas and development strategies of Jinchang City
ZHAO Wankui, ZHANG Xiaoqing, CHEN Zhiping, CHENG Xiaoyun, LUO Jianbo
2019, 36(11): 2989-2996. doi: 10.11829/j.issn.1001-0629.2019-0243
[Abstract](1265) [FullText HTML] (636) [PDF 840KB](22)
Ecological-functional regionalization is the basis of regional ecological protection, scientific management, and sustainable utilization of natural resources. In this study, data of soil erosion sensitivity and significance of water conservation were analyzed based on ArcGIS in order to partition different ecological-functional areas of Jinchang City. Five zones were partitioned: Ⅰ, forest-grass water conservation ecological barrier area in the southwestern mountain area; Ⅱ, circular economy ecological development area in the corridor; Ⅲ, xerophytic vegetation restoration area in the shallow hills and hills in the central part; Ⅳ ecological construction area in the northern Gobi area; Ⅴ, ecological protection area in the northern Gobi area. According to the characteristics of each area, the corresponding development measures were proposed, which may provide a theoretical basis for the eco-environment protection and the delimitation of the ecological red line.
Reference of agricultural ethics in grassland civilization for protection ecological environment in grassland regions of the Qinghai-Tibetan plateau
ZHOU Qiran, SHUAI Linlin, HU Jian, TIAN Lihua, CHEN Youjun, WANG Hui, ZHOU Qingping
2019, 36(11): 2997-3006. doi: 10.11829/j.issn.1001-0629.2019-0110
[Abstract](1394) [FullText HTML] (731) [PDF 482KB](28)
The qinghai-tibetan plateau is an outstanding area in terms of both ecological environment and grassland culture. Due to special geographical location and climatic conditions, human beings are more closely bonded to natural environment on the Plateau. For past hundreds and thousands of years, local nomads have been exploring a unique pathway to get along with grassland environment and resources. Agricultural ethics featured with the qinghai-tibetan plateau culture has been shaped, being woven into the local grassland civilization. In this paper, local agricultural ethics was examined at 4 points of grazing schemes, religion and faith of the nomads, life styles and relevant traditional laws; following features of Agricultural ethics was revealed within co-existence of the local nomads and grassland environment, such as " Not to interfere with farming season”, " Conservation of nature”, " Principle of moderation” , and " Follow the law of nature”. When ecological security becomes increasing important nowadays, well examining and deploying the grassland ethics of the qinghai-tibetan plateau plays critical role for improvement ecological environment in the region, even though the importance of scientific technologies and relevant laws and regulations.