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In order to investigate the effects of spring and autumn grazing on soil physical and chemical properties in Kansu wapiti(Cervus elaphus kansuensis), six grazing intensity plots were set up in this study, and the physical and chemical properties of 0–40 cm soil layer were analyzed. The results showed that 1) the soil bulk density of 0–40 cm soil layer increased with the increase of grazing intensity, especially to the surface soil (P < 0.01); 2) 0–40 cm soil moisture and soil organic carbon density Soil total nitrogen density and total amount, soil available phosphorus density and total salt content generally decreased with grazing enhancement, and soil moisture, total nitrogen, available phosphorus density and total salt content were significantly negatively correlated with grazing intensity(P < 0.01), soil organic carbon density was significantly negatively correlated with grazing intensity (P < 0.05), 0–40 cm soil layer plant root carbon accounted for total soil The proportion of organic carbon increased gradually with the increase of grazing rate, and it was positively correlated with grazing rate (P < 0.05). The density of total nitrogen in 10–20 cm soil layer was the largest, and the ratio of soil available nitrogen to total nitrogen increased with grazing. The total C/N ratio of soil layer and soil in 0–40 cm decreased with the increase of grazing rate. The research results can provide a scientific basis for revealing the interaction mechanism and sustainable management of grassland and livestock in the Qilian Mountains.
To explore the relationship between herb roots and anti-erodibility in the red soil region of southern China, we examined three herbs (Vetiveria zizanioides, Trifolium repens and Lolium perenne) that naturally grow in two types of soil (yellow-brown and red) in Hubei Province. The soil-root composite of the three herbs were collected from two types of soil, with a total of six soil-root composite treatments. Each treatment (including the control) was subjected to concentrated flow scouring (hydraulic flume: 4.00 m long, 0.20 m wide) under three different water-flow shear stresses ranging from 2.41 to 15.03 Pa. Soil rill erodibility and root parameters were measured to investigate the effects of different soil erodibility characteristics. Results show that roots strengthen soil erodibility significantly. However, the influence of roots varied for different herbs, with Vetiveria zizanioides and Lolium perenne showing the largest and smallest enhancement effects, respectively. Root length density (RLD) was the root parameter that had the largest effect on soil erodibility, as RLD provided the most accurate simulation (R2 ≥ 0.930) of the soil detachment capacity change of two soil-root composites. Root mass density (RMD) and root area ratio (RAR) also had large effects on soil erodibility. Root diameters of less than 1.0 mm increased soil-root composite anti-erodibility, with the most significant effects observed for root diameters of 0.5～1.0 mm (P < 0.01). Overall, we found that Vetiveria zizanioides is an important plant species that can improve soil and water conservation in the red soil region of southern China. Results from this study provide an herb selection reference for regional restoration projects and describe the relationship between root features and soil anti-erodibility.
To determine the effects of white clover (Trifolium repens) degradation on soil enzyme activities in apple orchards, protease, urease, sucrase, and phosphatase activities in soil were detected after white clover was cut and buried in an apple orchard in Luochuan and Xunyi in Shaanxi province. Results show that the activities of soil enzymes, including protease, urease, sucrase, and phosphatase, significantly increased after the buried white clover was degraded (P < 0.05), except for phosphatase activity after 3 months of degradation and urease activity in Xunyi after 6 months of degradation. Increases in protease and phosphatase activities were greatest after 6 months of degradation. The effect of buried white clover degradation on the activity of soil enzymes varied spatially, with stronger effects observed in the Luochuan orchard. Correlational analyses of 4 enzyme activities showed a significant positive correlation between urease and sucrase. In conclusion, degradation of buried white clover can increase soil enzyme activities and improve physicochemical properties of soil. However, the effect of buried white clover is related to the planting apple site and white clover degradation time.
The spatiotemporal variability of soil nitrogen content under alfalfa and Poa pratensis rotation systems was examined to explore the spatiotemporal distribution of soil nitrogen under different rotation systems. The experiment included four treatments, Poa pratensis→alfalfa (PA), alfalfa→Poa pratensis (AP), Poa pratensis→Poa pratensis (PP), and alfalfa→alfalfa (AA). Soil was sampled from depths of 0–20 and 20–40 cm each month, from April to October in the second year after planting. The total N and available N contents were measured. The results showed that, under the PA mode, dynamic changes in total N content at soil depths of 0–20 and 20–40 cm were observed, first decreasing and then increasing from April to October. Available N content at a soil depth of 0–20 centimeter soil first increased and then decreased, before increasing a second time; this up and down trend was observed for a soil depth of 20–40 cm. In the 0–20 cm layer, the soil total N content of PA was significantly higher than that of PP from April to October (except for August), while in the 20–40 cm soil layers, the PA mode was significantly higher than that of PP in all months except August and September. The soil available N content of PA was significantly higher than that of PP in different soil layers except for April(P < 0.05). Under the AP treatment, dynamic changes in total and available N content followed downward trends in different layers. In the 0–20 cm soil layers, the soil total N content under AP was significantly lower than that under AA in all months except April, May, and June (P < 0.05). In the 20–40 cm soil layers, there was no significant difference between AP and AA, except in October (P > 0.05). In the 0–20 cm soil layer, except in April, May, and June, the soil available N content of AP was significantly lower than that of AA in other months, and in the 20–40 cm soil layers,the AP mode was significantly lower than AA in October (P < 0.05). In summary, the Poa pratensis→alfalfa rotation system can significantly increase soil total and available N content, and the alfalfa→Poa pratensis rotation system can improve the utilization rate of soil total and available N content. Compared with alfalfa→Poa pratensis treatment, the Poa pratensis→alfalfa rotation system can effectively increase soil nitrogen content.
To clarify the response of soil microorganisms to intercropping systems, the characteristics of soil microbial functional diversity were studied under an intercropping model using the Biolog method. The results showed that a wheat || Isatis tinctoria intercropping model could improve the utilization of the soil microbial carbon source, and its AWCD value was higher than that of wheat monoculture 26, 29% (96 h). Furthermore, there were significant differences in the 10–30 cm (P < 0.05). The ability of soil microorganisms to utilize the carbon source decreased with increasing soil depth. Compared with wheat monoculture, in wheat || I. tinctoria intercropping, the McIntosh index and richness index were significantly improved. Wheat || I. tinctoria intercropping increased the intensity of soil microorganisms to six kinds of carbon sources. Intercropping systems can enhance the stability of the soil microbial community, and changes in the carbohydrate carbon source play an important role in the functional diversity of the soil microbial community (0–30 cm). An intercropping planting model can improve the physiological activity of soil microorganisms and promote the utilization of soil carbon sources; the effect of wheat || I. tinctoria intercropping is clear.
Since the amount of greenhouse gases carried by China's steppe and desert steppe ecosystems cannot be effectively quantified on a large scale in the region, this study utilized the greenhouse gas value (GHGV) model and land-use data to analyze spatiotemporal changes in steppe data. The two sets of simulation parameters (global and localized) were combined to simulate the storage potential of three major types of greenhouse gases (CO2, CH4, N2O) in China's steppe and desert steppe ecosystems in the past 25 years. During the study period, the area of the steppe and desert steppe showed a downward trend, and the storage potential of greenhouse gases was weakened. The stored greenhouse gas was reduced by 1.93 Pg·CO2-equivalent–1. Comparing the localization parameter with the simulation results of the model's own parameters, revealed that the simulated greenhouse gas values for the steppe and desert steppe ecosystems with localization parameters were larger than the simulated values using global parameters. Furthermore, this study found that the current research is faced with the challenge of quantitative difference from steppe area to steppe carbon storage, and additional in-depth research is urgently needed.
Soil is a major environmental factor that affects plant population dynamics. Spatial variations in physical and chemical properties of soil determine, to some extent, the spatial differences of plant population distribution. To investigate the spatial distribution of populations of the dominant plant Themeda japonica in Henan grassland, the spatial distribution pattern of the T. japonica population was evaluated on a regional scale using the point-and-spot combination method, and the relationship between the distribution features and soil factors was analyzed. The diffusion coefficient (C), clumping index (I), mean crowding (m*), and patchiness index (PAI) indicated that T. japonica populations were distributed in clumped pattern in each region. In addition, the T-test of variance/mean ratio, patchiness index, Cassie index (CA), and negative binomial parameter (K) revealed that the T. japonica populations in different regions presented a highly aggregated distribution pattern. RDA redundancy analysis showed that the soil factors that significantly affected the spatial distribution pattern of T. japonica populations included soil organic carbon, soil carbon-nitrogen ratio, and soil pH values in northern Henan (P < 0.05), while it was soil total phosphorus content (P < 0.01) in western and southern Henan. In general, there were significant correlations between soil organic carbon, soil total phosphorus, and the spatial distribution pattern of the T. japonica population (P < 0.01).
MODIS/EVI data from 2000-2014 were combined using the Harmonic Analysis of NDVI Time-Series (HANTS) and Maximum Value Composites method (MVC) to investigate spatio-temporal variations of vegetation EVI and its climatic factors. Trend line and correlation analyses were used to examine Xilin Gol League Grassland from 2000 to 2014, providing a scientific basis for the protection of vegetation. Results showed that the EVI value of different vegetation increased after May, peaking in July or August. The Warm Grassland Desert, Warm Mountain Meadow, and Swamp vegetation showed a downward trend, while other vegetation types showed an upward trend. Vegetation in most parts of the Xilin Gol League had no significant changes in spatial pattern. It keeps an improved trend in the vegetation that the Warm Grassland, Warm Desert Grassland, Warm Meadow Grassland, Alpine Grassland and Warm Desert in the central, southern, southwestern Xilin Gol League, Erenhot, Sonid Left, East Ujimqin, and West Ujimqin. However, the vegetation in Low-salinity Meadow, Improved Grassland, and Warm Grassland Desert showed slowly decreasing trends in the northern, southern, and western parts of the Xilin Gol League. Vegetation EVI was mainly controlled by mean temperature, precipitation, mean relative humidity, and sunshine hours, which is affected by the average wind speed. Temperature was the most important factor affecting vegetation growth. The correlation between EVI and meteorological factors was high in Low-salinity Meadow, Improved Grassland, Warm Grassland, and Warm Desert Grassland and low in Alpine steppe. The improved area was larger than the degraded area in Xilin Gol, and vegetation was mainly controlled by temperature.
The monitoring of remote sensing and research on the grasslands of Inner Mongolia is of great significance for the implementation of the national ecological engineering evaluation and related policy adjustments. In this study, Inner Mongolia is selected as the research scope, based on satellite remote sensing data, ground meteorological observation data and other statistical data. For which, we used the dimidiate pixel model to estimate the grassland coverage, analyze the spatial and temporal pattern of the grassland coverage from 2001 to 2016, and evaluate the responses to the changing climate factors. The restoration of grassland vegetation and the growth trends of the grassland have been quantitatively monitored and dynamically evaluated, which effectively reveals the restoration of grassland vegetation and the improvement of the grassland ecosystem. The results showed that the spatial distribution pattern of the grassland coverage in Inner Mongolia, over a 15 year period, gradually decreased from the northeast to the southwest, and the average annual grassland coverage was 37.90% with obvious meridional zonation. The grassland coverage of the northeast grassland area is the largest, the central steppe area is the second, and the western desert grassland area is the lowest. Overall, the trend increased with fluctuation. The grassland coverage increased from 35% to 38.84% during the study period. The average correlation coefficients between the grassland coverage and temperature is 0.058 (P > 0.05) and between grassland coverage and annual total precipitation is 0.269 (P > 0.05), indicating that grassland coverage was not significantly correlated with temperature and precipitation in Inner Mongolia.
There are many groundcover resources with island characteristics in Pintan Island. In this study, the line transect method was applied to investigate wild plant species that are potential groundcover resources on Pingtan Island. The analytic hierarchy process (AHP) was utilized to evaluate the application values in creating the understory groundcover community of sheltered forest or ecological groundcover landscapes based on the investigated plant species after the establishment of the evaluation system for wild groundcover species. There were 227 species of wild groundcover plants in Pingtan. Herbaceous species accounted for 78.26% of the total species. In the first level factors of the evaluation model, the weighted values of adaptability and ornamental effects were the highest with values of 0.383 0 and 0.277 6, respectively. In the second-level factors, the weighted value of the saline-alkaline adaptability was the highest, and the wind-resistance, covering power, whole ornamental effect, and ecological benefits were also high (all above 0.08). By this evaluation system, 54 desirable groundcover species including Ipomoea pes-caprae, Limonium sinense, Oenothera drummondii, and Lysimachia mauritiana were screened out from the initial investigated species on Pingtan island. Furthermore, focusing on the four habitats of coastal sand, bedrock coast, saline wetland, and coastal forest, several suitable plant configuration modes of groundcover landscape are proposed．
To explore the influence of Alternanthera philoxeroides invasion on herbaceous plant communities in southern Henan Province, we set up 20 invaded plots and 20 control plots in Xinyang City. Using mathematical statistics and quantitative ecological methods, we studied the differences in species structure between invaded and control communities, as well as the coupling relationships among morphological characteristics, biomass of A. philoxeroides, species diversity, and community stability, which could provide references for biological control and native biodiversity protection. The results were as follows: 1) Four α-species diversity indices and species distribution uniformity of DCA ordination of the invaded community were all higher than those for the control community. 2) As A. philoxeroides coverage increased, the Shannon-Wiener (R2 = 0.569, P = 0.001) and Simpson (R2 = 0.749, P < 0.001) diversity index all showed a significant binomial trend. 3) Simpson, Shannon-Wiener index, and the Pielou evenness index all had a significant negative regression relationship with A. philoxeroides biomass. 4) The invaded community stability rose with the increase in A. philoxeroides relative height, whereas it declined with the A. philoxeroides root-shoot ratio and the Pielou index increased. Our study indicated that the A. philoxeroides invasion seriously decreased the herbaceous species diversity and destroyed the stability of the native plant community in southern Henan Province; thus, we should develop effective control measures for preventing the spread of the invasion.
Switchgrass (Panicum virgatum) is a C4 perennial warm season grass. Several of the natural and agronomic traits of switchgrass, including its wide geographical distribution, low nutrient requirements, low production costs, high water use efficiency, high biomass potential, and ease of harvesting, make it an attractive biomass crop for biofuel production. We believe that improving genetics using biotechnology would be a useful way to take advantage of the potential of switchgrass. Here, we highlight advances that have been made in switchgrass biotechnology. These advances will help to improve switchgrass agronomic traits and breeding varieties.
The forage plants are important basis for developing grassland animal husbandry. With the development of high-throughput sequencing technologies, more and more biologists engage in the study of transcriptome sequencing in evaluation of forage germplasm resources, formation mechanism of important traits, the exploration of excellent genes and molecular marker development. In this paper, the authors have reviewed the current researches on transcriptome of forage plants in term of plant growth and development, adaptation mechanism of biotic and abiotic stress (saline-alkali, extreme temperature, drought, nutrition deficiency and heavy metal), stress transcription factor discovery and molecular marker development. In addition, the future research trend of high-throughput sequencing technologies in forage plants was also prospected.
In this study, five populations of wild Medicago falcata from Xinjiang were examined. The genetic diversity of phenotypic traits in primitive populations was evaluated by analyzing the correlations, principal components, variability of distribution area, and variability of 20 phenotypic traits (including leaf, flower, and stem nodes) to provide valuable information for future research on genetic variation and germplasm innovation. Results showed that differences among populations were highly significant for all traits except leaf length and petiole length, though differences in these traits were still significant. Additionally, we found that M. falcata has rich polymorphism. The average coefficients of variation of phenotypic traits were 20.19% and 27.66% in the population and inter-population , respectively, which indicated that the main phenotypic differences of M. falcata came from the inter-population . Different degrees of correlation occurred among the 20 phenotypic traits. Negative correlations were observed between the number of branches and latitude and longitude, plant height, and altitude. Results also showed that the 20 phenotypic traits can be classified into 6 principal component factors with an accumulative contribution rate of 71.75%. The variation of phenotypic traits between populations was primarily due to leaf, internode, and flower features.
Abscisic acid (ABA) is an endogenous hormone that plays an important role in regulating plant growth and development, and abiotic stress and biotic stress responses. Pyrabactin resistance 1-like (PYR/PYL) protein is a core regulatory component of the ABA signaling pathway. However, details about this family in Medicago truncatula are unknown. This study used BLAST method to identify members of the PYL family in the M. truncatula genome based on the 14 PYL genes in Arabidopsis thaliana. Consequently, 14 members of the PYL gene family were identified, all of which contain the PYR-PYL-RCAR-like domain. The cis-elements in the predicted promoters revealed that all the members of PYL gene family contain elements associated with stress and hormones. Gene Ontology (GO) enrichment analysis and KEGG pathway analysis show that members of the PYL family are mainly involved in the abscisic acid signaling pathway and that they respond to external stimuli. Analysis of gene expression patterns showed that they exhibit specific expression patterns under stress. This study lays the foundation for further studies on the PYL genes in M. truncatula.
The effects of different concentrations of Pb2+, Cd2+, Cu2+, and Zn2+ on the growth and physiological characteristics of Pelargonium hortorum were studied. Results showed that the growth of P. hortorum stressed by four types of heavy metals was inhibited by different degrees, with root length being the most significantly inhibited. However, despite this inhibitory effect, the plants continued to grow. With increasing concentrations of heavy metals, the plant biomass decreased, whereas leaf relative conductivity was significantly increased (P < 0.05). Chlorophyll, soluble protein, and free proline contents and catalase(CAT), superoxide dismutase(SOD), and peroxidase(POD) activities were significantly (P < 0.05) higher intreated plants than in the control plants. Plants did not show obvious withering when Pb2+ concentrations were less than 1 000 mg·kg–1 and Zn2+ concentrations were less than 800 mg·kg–1, whereas under other treatments, two or three basal leaves had withered and abscised. Therefore, P. hortorumshows some tolerance to four different heavy metals, and was fix potential of the types for using the heavy metal contaminated soil.
Stress caused by different NaCl concentrations, germination proportion chlorophyll content, proline content, MDA content, and soluble sugar content were measured during the germination and seedling period of six grass species. As NaCl concentrations increased, proline content and MDA content in leaves of all six grass species increased. Chlorophyll and soluble sugar content first decreased and then increased as NaCl concentrations increased. The membership function was used to evaluate the antisalinity of six grass species in germination and seedling periods. Results revealed the following order of salinity tolerance for the six grasses (from largest to smallest): Bromus inermis > Alopecurus pratensis > Roegneria grandiglumis > Elymus breviaristatus Tongde > Agropyron cristatum > Roegneria pauciflora Tongde.
The dynamic variations of nutrient and phenolic content in Sophora davidii in a Karst region of the Guizhou Province were investigated in the study. Results showed that the content of crude protein in the vegetative, flowering, and seed set stages was higher than in the maturation stage (P < 0.05). The content of nitrogen free extract, crude ash, and ether extracts decreased with the increasing growth period (P < 0.05). The content of dry matter, crude fiber, acid detergent fiber, neutral detergent fiber, and calcium increased with the increasing growth period (P < 0.05). The content of tannin had no significant relationship with the different growth stages (P > 0.05); however, other phenolics decreased with the increasing growth period (P < 0.05). The content of tannin in the flowering and seed set stages was more suitable for feeding animals than in the vegetative stage, while higher crude protein and relative forage values were also obtained in the former. Considering all factors, we suggest that the best utilization period for feeding animals with Sophora davidii is from the flowering to seed set stages. This study can provide theoretical support for the efficient use of Sophora davidii in animal husbandry in the Karst areas of Guizhou Province.
This study investigated the effects of population density and community structure on seed production of Vicia sativa in a cool climate region. We analysed and compared the seed yield, seed quality, seed yield components, and other biological characteristics of different sowing rates, sowing ratios, and patterns (mixed cropping and intercropping with Avena sativa). Results show that seed yield increased with increasing sowing rates. The seed yields of mixed cropping and intercropping were less than that of monoculture, but seed quality (germination potential) was better. Seed yield and quality increased with increasing V. sativa sowing ratios. The mixed patterns affected seed yield and quality. Population density and community structure influenced shoots per plant (Sh/P), pods per plant (Po/P), and, in some cases, pod length, seeds per pod, and germination rate. In the mixed cropping and intercropping systems, A. sativa was a stronger competitor than V. sativa. To increase V. sativa seed yield and seed quality, the competition ratio of V. sativa in mixed communities needs to be improved by increasing the mixed ratios of V. sativa and using an intercropping pattern. In conclusion, V. sativa seed fields need higher sowing quantities (equal or more than 120 kg·ha–1), 75% V. sativa seeding rate + intercropping pattern, and higher mixed ratios in cool climate pastoral areas.
To reveal the effects of oat variety, fertilizer, and legume mixture on plant nitrogen storage and allocation patterns, we examined the effects of four levels of nutrient addition and four legume mixture levels on four oat varieties in an orthogonal experiment [L16(45)]. Results showed that aboveground and belowground plant nitrogen storage was affected by variety, fertilizer, and mixture. Fertilizer had the largest influence on oat leaf nitrogen storage, and both variety and fertilizer influenced root nitrogen storage in oats. The legume mixture had a large influence on stem, leaf, and root nitrogen storage in legumes. Under the Avena sativa ‘Qinghai’, urea + diammonium phosphate + organic fertilizer and a mixture level 75 kg·ha–1, above and belowground nitrogen storage increased during the milk period. Aboveground plant nitrogen storage increased during the growth period, but belowground nitrogen storage decreased. Variation in the aboveground biomass increased, stem and leaf increased first and decreased later, and root nitrogen storage of oats, decrease. The aboveground biomass, stem nitrogen storage, and leaf nitrogen storage of legumes increased, but root nitrogen storage decreased during the growth period.
To explore the effect of maize || white clover intercropping under different row spacing in the Karst area of Guizhou, maize || white clover intercropping and a corn monoculture were grown using 30, 50, and 70 cm row spacing. Photosynthetic characteristics, maize ear characters, yield, and rhizosphere soil respiration were monitored. The results showed that except for the 50 cm row spacing treatment, the diurnal variation in the photosynthesis rate of maize leaves in each test group and control group exhibited a double peak curve. The lowest daily mean of intercellular CO2 concentration in maize leaves, the highest utilization rate of CO2, and the highest daily average photosynthetic rate were under the 50 cm row spacing treatment. Under this treatment, the corn yield was significantly increased (P < 0.05). Line spacing processing of 30 and 50 cm increased the fresh straw yield, and the whole plant total yield significantly increased (P < 0.05). Corn yield, fresh straw yield, and total yield of whole plants were the lowest in the 70 cm row spacing treatment (P < 0.05). Different treatments had no effect on stomatal conductance, transpiration rate, grain number on the cob, and ear length (P > 0.05). The effects of intercropping on soil respiration inhibition was not obvious; however, different row spacing planting modes influenced soil respiration. The 30 cm row spacing planting mode had the best effect on soil respiration inhibition, which reduced carbon emission, followed by the 50 cm row spacing planting treatment. Therefore, 30 cm or 50 cm row spacing maize || white clover intercropping was the most suitable for harvesting fresh straw in the Guizhou Karst area. The 50 cm row spacing maize || white clover intercropping was the most suitable when corn seeds or seed and straw were harvested at the same time.
To enrich the forage germplasm resources of the irrigated area in Ningxia, a randomized block design was adopted to study the adaptability of ten Sorghum varieties from April to October 2017. The study examined the agronomic traits, nutritional value, and the anti-lodging coefficient. An analysis of the correlation between the various indicators of the anti-lodging coefficient, principal component analysis among the nutrition indexes, and the comprehensive score of nutritional content was conducted. The subordinate function was conducted to evaluate the different sorghum varieties. The results showed that the ten sorghum varieties had a growing period of 113～125 days, the tallest variety was Lvjuren (312.67 cm), the highest hay yield was from Hainiu (29.72 t·ha–1), and there were significant differences among the varieties (P < 0.05). The longest stem Brix was Dalishi (16.37%), the range of chlorophyll content was from 26.97～51.95 (SPAD), the highest quality forage variety was from Dajiang 2120, which is 154.33, and the top 5 varieties from the comprehensive evaluation of nutritional content scores were: Dajiang 2180 >Siweite > Dajiang 2120 > Jinguan > Lvjuren. The top 5 varieties regarding the coefficient of lodging resistance were Dalishi, Dajiang 2180, Hainiu, Lvjuren, and Dajiang 2120. Dajiang 2180, Dalishi, Lvjuren, Hainiu, and Dajiang 2120 were widely popularized and cultivated in the irrigation area in Ningxia, based on the comprehensive evaluation of nutritional content, hay, and the anti-lodging coefficient.
In order to enrich and exploit forage germplasm in China, we examined the agronomic traits and forage potential of Pterocypsela indica ‘Dianxi’ in Dai-Jingpo Autonomous Prefecture of Dehong in Yunnan. Results showed that ‘Dianxi’ has good adaptability in the tropical area of Yunnan. The growing period of ‘Dianxi’ lasted from 202 to 206 days. In addition, this species has good seeding performance, with a higher seed yield of 94.75 kg·ha–1. The average forage yields of ‘Dianxi’ in two growing seasons were 2.56 times more than ‘Mengzao’. The regeneration and forage-balanced supply of ‘Dianxi’ were better than those of ‘Mengzao’, and it can be cut five times per year. In conclusion, P. indica ‘Dianxi’ has greater potential on grassland establishment and pasture restoration in the tropical area in Yunnan and southern China.
The performance and nutritional quality of eight annual forage crops were analyzed in Ya'an and Renshou of Sichuan. The results showed that Jincao 8 and Jincao 11 (forage sorghum) had good growth potential in both pilots. The plant height, dry matter (DM) yield, crude protein (CP) yield, and water-soluble carbohydrates (WSC) yield were significantly higher (P < 0.01) than for other varieties, and relative feed value (RFV) exceeded 125.00 (Jincao 11, except in Ya'an, is 114.39). Jincao 11 had the highest DM yield in Ya'an, which was 20.11 t·ha–1, followed by Jincao 8 and Zhenghong 311 (silage corn), In Renshou, Jincao 8 had the highest DM yield, which was 10.39 t·ha–1, followed by Jincao 11 and Zhenghong 311. The CP and WSC yields of Jincao 8 were the highest in Ya'an, followed by Jincao 11. The CP yield of Jincao 11 was the highest in Renshou, followed by Yayu Silage 8 (CK, silage corn) and Zhenghong 311. Furthermore, Jincao 8, Yayu Silage 8, and Zhenghong 311 had the highest WSC yield. Based on the yield and quality of Jincao 8, Jincao 11, and Zhenghong 311, these forage crops are suitable for cultivation in two pilots.
The experiment aims to establish a near-infrared fast-prediction model which measures the nutrition components of rapeseed straw using near-infrared reflectance spectroscopy (NIRS). 125 rape straw samples were collected from Gansu Province, Qinghai Province and Ningxia Hui Autonomous Region, and then the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), coarse ash (Ash), neutral detergent insoluble protein (NDIP), acidic detergent insoluble protein (ADIP), acid detergent lignin (ADL), non-protein nitrogen (NPN) and soluble protein (SP) of the samples were determined. 100 rape straw samples were selected as calibration set to build calibration models. Another 25 samples were used as external validation set to evaluate the NIRS prediction model. The results showed that: 1) the contents of DM, CP, NDF, ADF, EE, Ash, NDIP, ADIP, ADL and NPN in rape straw were 93.62%, 5.85%, 67.22%, 55.40%, 2.57%, 7.66% and 1.04%, 0.63%, 13.58%, 1.70%, respectively. 2) The coefficient of determination for cross-validation (1-VR) and coefficient of determination for calibration of DM, CP, NDF, EE, Ash, NPN and SP were greater than 0.9 and 0.84, respectively, indicating that these NIRS models could be used in routine analysis. 3)The model parameters of DM, CP, NDF, EE, Ash, NPN and SP were Standard MSC 1,4,4,1, Weighted MSC 2,4,4,1, SNV 2,4,4,1, Standard MSC 1,4,4,1, SNV and Detrend 1,4,4,1, Weighted MSC 1,4,4,1, respectively, whereas the model of other nutritional components is not ideal and needs further improvement. In summary, the availability of nutritional composition correction model for rape straw was verified by internal and external validation.
Gut microbiota play important roles in host physiological activity, immune regulation, and health. Although numerous studies have found that gut microbiota of plateau pikas are related to food and environment, the differences of gut microbiota between wild and laboratory-reared plateau pikas are still unclear. In this study, we used 16S rRNA gene high-throughput sequencing technology to compare the differences of gut microbial communities between wild and laboratory-reared plateau pikas. Our results suggested that laboratory-reared plateau pikas had higher abundance of Bacteroidetes and Spirochetes, but lower abundance of Proteobacteria and Actinobacteria than wild plateau pikas. There was 50.1% overlap of gut operational taxonomic units (OTUs) between wild and laboratory-reared plateau pikas, while 49.9% of gut OTUs were specific in the wild and laboratory-reared plateau pikas. Significant differences were detected in both composition and community structure (β diversity) of gut microbes in the wild and laboratory-reared plateau pikas. Therefore, laboratory-reared plateau pika could not effectively reflect the gut microbiota of plateau pika in the wild.
The effect of growth stage and lactic acid bacteria additives on fermentation quality and nutritional value of Jerusalem artichoke silage were studied. Fresh artichokes at two different growth stages (early bud stage and blooming stage) were ensiled, with (5 × 106 cfu·g–1 LAB) or without a lactic acid bacteria additive, in poly bags for 60 d. The results were as follows: 1) During the blooming period of the Jerusalem artichoke, the pH and ammonia-nitrogen/total nitrogen value of the silage added by the lactobacillus significantly decreased (P < 0.05), while the contents of lactic acid and acetic acid significantly increased (P < 0.05). In addition, the content of lactic acid was significantly decreased (P < 0.05), while the content of acetic acid and the ammonia-nitrogen/total nitrogen value were significantly increased (P < 0.05) in the lactic acid supplementation group of artichokes in the early bud stage. 2) Compared with silage from artichokes harvested in the early bud stage,pH, acetic acid, crude ash, and in vitro dry matter digestibility of silage from artichokes harvested in the blooming stage decreased significantly (P < 0.05), and the lactic acid and water-soluble carbohydrate contents increased significantly (P < 0.05). It can be concluded that addition of lactic acid bacteria to Jerusalem artichoke during the blooming period led to higher fermentative quality.
Twenty strains of lactic acid bacteria were isolated from sugarcane sheaths packed in silage for 0–90 d and fermented by traditional culture. The isolated and purified strains were identified by morphological observation, API 50CH biochemical kit identification, and 16S rDNA sequence analysis, and their acid production capacity was determined. The results showed that strain Y42 was Lactobacillus casei, strains Y32 and Y59 were L. paracasei, and all other strains were L. plantarum. After fermentation for 18 h, the strains’ fermented liquid pH values can be reduced to less than 3.70. The pH of strain Y67 was the lowest at 3.57. The 20 strains of lactic acid bacteria isolated from sugarcane sheaths showed a strong capacity for producing acid and good silage potential. These strains could be used for preparing fermentation agents for silage.
In vitro method were used in this experiment to study the relationship between different types of roughage and different roughage and concentrate feed combinations with various GI indexes. The results of this study will provide important information that can be used to match feed and diet when preparing for production. For the multiple-factors associative effects index (MFAEI), corn silage and Leymus chinensis had the highest combination effect (1.40), followed by corn silage and brewer's grains (1.07). The combination of L. chinensis and rice straw was the lowest, with an MFAEI of 0.52. In addition, positive combination effects were observed between different roughage and concentrate combinations. Among them, the corn silage and L. chinensis concentrate had the highest MFAEI (0.37), followed by the L. chinensis and rice straw concentrate (0.36). The corn silage and beer lees concentrate was the lowest with an MFAEI of 0.24. This shows that in production practice, the GI index can be used together with the combination effect to make rational use of roughage and concentrate. This increases positive associative effects, controls negative associative effects, prevents feed waste, and improves animal production performance.
The overall aim of the study was to provide a theoretical basis for the improvement of the fermentation characteristics and nutritional quality of Sudangrass (Sorghum sudanense) silage. We investigated the effect of homo- and hetero-lactic acid bacteria on yeast community structure and fermentation characteristics during the silage process of Sudangrass. The control (CK) had no added inoculant; the LP group contained Lactobacillus plantarum; the LB group contained L. buchneri; and the LP + LB group contained L. plantarum and L. buchneri. All additives were added to Sudangrass and sealed in a vacuum bag. The indices of chemical characteristics, fermentation characteristic, microbial populations, and species were analyzed to evaluate the dynamic change of the yeast community and fermentation characteristics during 1, 7, 15, and 60 days. The results showed that yeast species decreased in all of the treatments during fermentation, and the number of yeast was below the limit of detection in the LB and LP + LB groups after 60 day. Compared with CK, the addition of the homo- and hetero-lactic acid bacteria can significantly decrease pH, propionic acid, butyric acid, ratio of lactic acid to acetic acid, NH3-N, and number of yeast species, and significantly increase lactic acid and the number of lactic acid bacteria (P < 0.05). The treatment V-score was ranked in the order: LP > LP + LB > LB > CK.
Xilingol League has undergone great changes since the 1980s, with regard to the grassland ecosystem, industrial structure, and the life of herdsmen. Xilinhot City has attracted extensive attention from researchers and practitioners because it is the political, economic, and cultural center of Xilingol. We conducted a systematic review of sustainable studies in this area to understand the relationship between grassland ecosystem service and human well-being. The results showed that the research topics mainly include grassland ecosystem, herdsmen wellbeing, climate change and natural disasters, industrial structure and development, and urban ecology. Under the impacts of climate change, disasters, and grassland/livestock ownership reforms, the grassland ecosystem services in Xilingol and Xilinhot, especially the provisioning service, showed a decline, which had an important impact on the income and well-being of herdsmen. In order to restore the grassland, a series of policies were introduced and achieved some successes. The main industries include animal husbandry, mining, and tourism. Animal husbandry is the most important source of income for most herdsmen, and it is affected by the grassland ecosystem, climate, and human activities. The mining industry has increased government income and promoted the development and construction of cities, but it has had many negative impacts on the local ecological environment and life of herdsmen. Transformation of the development of the mining industry to improve the well-being of local residents and sustainability is a major challenge for Xilinhot City. Tourism accounts for a small share of economic growth, but it is growing rapidly and is expected to become an important source of income for herdsmen to increase their diversity of livelihood. We found that previous studies mainly focused on a single issue, while few studies on comprehensive sustainability have been conducted. It is necessary to conduct comprehensive interdisciplinary research and provide a scientific basis for local sustainability research.
The undergraduate thesis is an important part of undergraduate cultivation, which can systematically examine students’ ability of using the knowledge acquired in undergraduate period. In this study, we investigated the change pattern of the research fields of undergraduate thesis for Pratacultural Science majors at Lanzhou University by using the moving average and the linear regression equation methods, and also compared the participation proportion of Pratacultural Science undergraduates in scientific research items and number of publishing papers in main Chinese universities. The results showed that: 1) In the main topics of undergraduate thesis were a largely increasing, such as grassland ecology, stress physiology, and grassland protection, accounting for 31.4%, 16.7% and 15.0%, espectively, but forage germplasm resources and breeding was a quickly decreasing, accouniting for 17.0%. 2) Universities offering Pratacultural Science in China have attached great importance to undergraduate scientific training and undergraduate thesis quality, but a few number of papers were published by undergraduate students. In order to improve the quality of undergraduate thesis, we suggest that the students should positively participate in scientific innovation training, and higher education institutions should strengthen the papers writing in core courses for Prataculatural Science majors, and the teachers and students should pay more attentions to the topics selection, experiment and writing time of thesis, and the teacher’s advice effect and the thesis evaluation and examination.