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Cultivatingagriculture was a stage of production between the nomadic agriculture and the modern agriculture. As far as Loess Plateau was concerned, nomadic culture emerged first then followed by agrarian culture. The two cultures coexisted for a long time and alternately took over the dominate position. Finally the agrarian culture settled down firmly on the Loess Plateau with the farming agriculture getting stabilized after undergoing 11 stages and 8 changes during thousands of years. But it had been in a difficult situation since its environment has changed, which affected the foundations favorable to the agrarian culture for such a long time. Grasslandagriculture had advantages in soil fertility maintaining, fertilizer saving, water and heat saving and profit promoting in comparison with cultivatingagriculture. Therefore, shifting from cultivatingagriculture to grasslandagriculture was an inevitable historical tendency, which may also be regarded as a revival of the agricultural culture in Zhou Tsutime. It was this revival that provided a necessary condition for conversion of cultivatingagriculture to grassland agriculture.
Typical Stipa Breriflova steppe in Xinghai, S. purpurea grassland in Maduo and alpine meadows in Dari, Zaduo, Qumalai and Tanggulashan counties were selected for studying the community character in source regions of three rivers with quadrats investigation. The results showed that 1) the richness of alpine meadow in Dari and Qumalai counties were higher, and there were 20 and 15 species (P＜0.05).The species were 8 in Xinghai, Maduo and Tanggulashan, separately, but it was only 5 in Zaduo (P＞0.05). 2) The diversity was the highest in Dari and Qumalai at 2.74 and 2.27. Moreover it was the lowest in Tanggulashan and Zaduo, and it was about 1.5. The species diversity of Stipa steppe in Xinghai and Maduo both were 1.87. The Pielou index was lower in Tanggulashan and Qumalai at 0.76 and 0.84, then that were higher in other plots. The statistics showed that there was significant correlation between diversity and species(r=0.967, P＜0.01), the equation was y=1.130 1+ 0.079 5x (R2= 0.935 9, P＜0.01). 3) It was revealed that the alpine meadows of Zaduo and Qumalai were first classified into one group by clustering. Then alpine meadow of Tanggulashan was injected. After that the Stipa Breriflova steppe of Xinghai, alpine meadow of Dari were attributed to the group, and Stipa purpurea steppe in Maduo was clustered one group finally.
In this paper, we studied the propagule weight of 43 plants at the alpine meadow in the source region of three rivers of Tibetan Plateau. There were great differences in their weight, and minimal single grain weight was less than 0.03 mg, and the biggest was over 5 mg. The propagule single grain weights of 15 species (accounting for 35%) were less than 1 mg, and these species might have persistent soil seed bank. The propagule of perennial herb was heavier than annual herb (P0.05). The propagule of weed was heavier than quality forage (P0.01). The propagule weight of Compositae species was evidently larger than that of Gramineae and Sedges species (P0.05). The appendages of propagule played an important role in dispersal and establishment of plants, the propagule of 75% Compositae species had pappuses, they might be dispersed by wind easily, and the propagule of 89% Gramineae species had awns, these species were not likely to be dispersed.
Due to the drought climate and overgrazing, the grassland degraded severely, which not only influenced local environment, but also threatened ecology safety of areas around Beijing and Tianjin. Urgent control of degraded grassland and prevention of further deterioration was needed. Xilamuren grassland in Inner Mongolia was located in arid desert grassland area. After years of overgrazing, the grassland vegetation and soil degraded severely and the soil erosion was serious. But the degradation was not fatal yet, the grassland has not become desertification and salinization. So enclosing the grassland and letting it rehabilitate naturally, obvious effect would acquire after just 2 or 3 years. The related observation and research indicated that the yield of the grassland increased to 4.6 times, grass height increased to 9.2 times and coverage increased to 1.6 times after successive three years enclosure and natural rehabilitation. The grass community structure and the soil improved ecologically. The conservative function of the grassland strengthened greatly. The soil erosion decreased by 20%.
From October 2008 to May 2009, changes of electrolyte leakage rate in leaves, stems and rhizomes of three warm season turf grasses (Zoysia japonica Lanyin No.3, Cynodon dactylon Yangjiang and Eremochloa ophiuroides E126), which in simulated cold treatment were determined with improved conductivity method, and the freezing lethal temperature of 50%(LT50) was estimated by the means of fitting Logistic equation, as well as the seasonal dynamic changes and differences of cold tolerance among different organs were analyzed, comparatively. The results indicated that LT50 in leaves, stem and rhizomes of three warm season turf grasses showed decreased firstly then increased sharply with seasonal changes in field temperature which was dropped in overwintering and increased in spring. The rhizomes of Z. japonica Lanyin No.3, the rhizomes of C. dactylon Yangjiang and stems of E. ophiuroides E126 showed better cold tolerance .In summary, Z. japonica Lanyin No.3 had the greatest cold tolerance, E. ophiuroides E126 was second, and C. dactylon Yangjiang had poor cold tolerance by analyzing the dynamic seasonal changes of LT50 and observing the phenophase in field.
The rodents and insects are becoming more and more serious in grassland. It is one of important factors to grassland degradation, desertification and soil erosion, and further threaten the sustainable development of grassland animal husbandry. As a syntaxic technology, remote sensing has the following advantages: wider detective range, more information, lower cost, and less limitation to ground condition and human activity, spatial information and environmental messages can be collected, handled and updated quickly, flexibly, accurately and reliably. 3S technologies combined with the data collected from ground investigation can not only monitor the grassland on a macro scale, but also reflects the dynamics of the rodent and insect pests accurately. This paper was summarized the principles, methods and existed problems in monitoring the grassland pests with the 3S technologies, and analyzed the important content in this field study and the prospect of the application in the future.
In this paper,the alien species of Conyza canadensis in Dongting area was studied, its biology and harmfulness characteristic were revealed, stem and leaf growth rule, accompanying plant, distribution, propagate types and hazards causes were analyzed comprehensively. This plant had characteristics such as abord distribution, batter adaptability, faster reproduction and grave hazard to crop. This paper provided important information for comprehensive control and utilization of C. canadensis.
Wetland was one of the biggest global ecosystems together with forest and sea ecosystems with its special function. The ecological function of wetland played an irreplaceable role in terms of social harmonic development with nature, and sustainable social economic development. In recent years, with the economic development and society progress, more and more attentions had been paid to wetland ecosystems and its protection. As a unique city where Yellow River flowed through, the protection and reasonably utilization of Lanzhou urban area wetland resources was not only the foundation of constructing Lanzhou landscape city, but also the basis of urban ecological environment construction. This paper aimed at the types and distribution, present situation and existing problems of Lanzhou urban area wetland resources, proposed the protection and utilization approach of Yellow River wetland resources to provide reference for reasonably utilizing wetland resources.
The indoor bioassay and physiological methods were adopted to explore the allelopathy and mechanism of Scirpus triquetet with three plant receptors. The results showed that aqueous extract of S. triquetet had allelopathy on wheat, radish and cucumber, and its inhibition effect gradually strengthened with increasing polarity of extraction. At the same time, the different extraction components had different inhibition effects on the growth of three plant seedlings, which mainly reduced the root activity; inhibition effects on plant seedlings root showed as increased production of MDA, and increased activity of POD, lowered CAT activity and content of CHL, which showed that S. triquetet had the function of allelopathy on wheat, radish and cucumber.
As the second element in the earth's crust, silicon evidently benefits plant growth and development. After discussing the silicon distribution in plants, channels of assimilating silicon for plants, as well as the positive role of silicon on stress condition, some enlightenments of silicon nutrients to turf grass and turf management research were drawn as following: Firstly, addition of silicon could promote turf grass growth and shorten the duration of turf establishment; secondly, it could improve water use efficiency in order to save water resources for irrigation turf; thirdly, addition of silicon could improve the turf grass resistance to abiotic stress, it could increase the possibility area of establishing turf; fourthly, silicon application would reduce the amount of nitrogen and phosphorus fertilizer in turf grass management, and mitigate soil degeneration; finally, silicon application would improve turf grass resistance to biotic stress, and decrease the use of pesticide in turf management.
The desert steppe of Alashan Inner Mongolia had thousand years of utilization history, which was a traditional nomadic region. Aboriginals of Mongolian who living in Alashan had formed a set of integrated traditional ecological culture on grassland protection. But with the development of the history, the traditional ecological culture was replaced by the ecological policies which were made by government. Comparison traditional ecological culture with grassland ecological policy showed that the policy had some disadvantages, such as the short coverage, bad continuity as well as compulsory implement. According to the comparison results, three proposals were presented: i.e., 1)increase awareness of environment protection of herdsmen, and rebuild ecological values; 2) develop traditional legal system and reestablish the reward and punishment system; 3) take from grassroot to the top way when making ecological policies.
With the development of bidding system of the greening engineering, construction of greening engineering tend to standardization accordingly. This paper discussed related measures of strengthening and improvement in greening engineering management, including organizing design such as preparation, reasonable schedule, staff allocation, on site management such as construction organization, making planning, inspection and supervision, cost management such as strengthening cost management, improving management policy and budgeting, and quality management such as material quality control, construction methods and sequence. Case study was also used to analyze and evaluate the effects of these management measures.
A field experiment was conducted to study the effect of spraying PP333 before jointing on plant height, dry matter accumulation and seed yield of annual ryegrass (Lolium multiflorum var.ganxuan No.2). The results showed that PP333 could inhibit the plant height significantly. With the increasing of PP333 concentration, plant height decreased. PP333 promoted dry matter accumulation and transfer within certain concentration. The dry matter accumulation of treatments in heading stage and mature stage, and the transportation amount before heading were both significant higher than CK. But spraying too much PP333 could decrease the accumulation and transfer of dry matter significantly. Yield components responded differently to PP333, grain weight was less influenced, while grain number per spike and spike number were significantly influenced. Path analysis showed that PP333 had the most effect on spike number which was the key factor in output. The annual ryegrass lodged and shattered severely in mature stage, PP333 could decrease shattering rate and inhibit these phenomena effectively, and the inhibition increased with the increasing of PP333 concentration.
The diurnal variation of photosynthesis of 5 wild Dichondra repens Forst. in southwest of China were measured by a Li6400 portable photosynthesis system, and the differences of photosynthesis characteristic were compared. Results showed: 1) With natural illumination, the net photosynthetic rate (Pn) diural variations of 5 accessions showed a double peak curve with the 1st peaked at 12:00 and the 2nd at 16:00, and there was typical midday depression. 2)The diurnal mean transpiration rate (Tr) value of unit area and the diurnal mean value of available water use efficiency (WUE) of 5 accessions were significantly different. The diurnal mean Tr value of SD10 was far more higher than the others, and it was strong transpiration material. The WUE of SD11 was the highest which can produce more biomass than the others when given the same amount of moisture. The adaptations to light of 5 wild D. repens were different, GD03 with a high light saturation point[1 051 mol/（m2s)] and a low light compensation point[28.2 mol/（m2s)] was resistant to shade, and adaptive to the strong solar radiation. It was chosen for further study as an outstanding turf grass germplasm resource with excellent turfused characteristics.
The paper studied the effect of rainwater harvesting planting measure with mulched ridges on growth and development of Elymus sibiricus L. in northern agricultureanimal husbandry ecotone. It suggested that rainwater harvesting with mulched ridges could make the limited rainfall converged abundantly in the furrow, and the efficiency of ridge surface running amounts to about 80%. In vegetative growth stage of E. sibiricus L. in 2008 and 2009, the differences of the height in treatments were significant respectively (P0.05). In 2008, the plant height in MR60 increased by 33.5%61.3% compared with CK, MR30 increased by 20.1%44.1% compared with CK, and MR60 increased by 9.2%16.2% compared with MR30. In 2009, the plant height in MR60 increased by 93.2%116.4% compared with CK, MR30 increased by 65.4%82.3% compared with CK, and MR60 increased by 12.1%19.4% compared with MR30. The differences of density among MR30, MR60 and CK were not significant, but the MR30 and MR60 both were higher than CK, generally.Density dynamics kept the same pace with the variation of average tillers in 2008, the density wholly decreased slowly and tended to stable after turning green in 2009.
Under low temperature stress of 5 ℃ and 15 ℃, the physiological and biochemical indexes related to cold resistance in the leaves of two kinds of new material of forage maize SAUMZ1 No.1 and No.2 were investigated after the treatments of 6, 24, 48, and 72 hours. The change of physiological and biochemical indexes under different low temperature was compared, and the cold resistance of two kinds of new material was analyzed. The results showed that the forage maize SAUMZ1 No.1 had integrity plasma membrane and lower production of MDA, and induced more proline content with the temperature dropped. So forage maize SAUMZ1 No.1 was more cold tolerance than No.2 according to the three physiological indexes.
Based on the randomized block design for five nitrogen fertilizer levels of N0, N90, N180, N270, N360. Effects of fertilizer N on the height, the stem/leaf, yield and the organic distribution of nitrogen on Sorghum hybrid in Yangzhou region of Jiangsu province were studied, at the same time the economic benefit was accounted. The results indicated that application of nitrogen fertilizer increased the economic benefit significantly. The highest increase was 6 046 yuan/hm2 in 2008. The yield and plant height increased with the increase of nitrogen fertilizer, the fertilizer of N360 was the largest amount in the first crop and the fertilizer of N270 was the largest amount in the second and third crop. However, the effects of the nitrogen fertilizer on the stem/leaf mostly perform the znd harrest stage. The total nitrogen of S. hybrid concentrated mostly on the leaf, and the high fertilizer N treatment was larger than the low fertilizer N. The contents of total nitrogen in different organs varied as the leaf＞the whole plant＞stem＞sheath.
The effects of applying nitrogen, phosphorus and potassium fertilizers on the yield and growth performance of silage maize were studied with field plot experiment and the results showed that the growth of silage maize was obviously improved by fertilization. With the increase of nitrogen application, the growth stage and harvest time were postponed while phosphorus and potassium fertilizers have little effect on the growth period. The application of nitrogen fertilizer promoted the growth of silage maize, but higher application (urea 360 kg/hm2) could easily cause lodging. Potassium fertilizer could improve the lodging resistance. The yield of silage maize could be increased by proper application of nitrogen and potassium fertilizers.
NaCl was used as stress factor, six alfalfa varieties were treated with 0, 0.3%, 0.5%, 0.7% and 0.9% NaCl, and the salt tolerance was tested by measuring potentiality of germination, the germination rate, plant height, root length, soluble sugar content and MDA content of Medicago sativa plants. The results indicated that the potentiality of germination and the germination rate were decreased, and the plant height and root length were shortened, but soluble sugar content was increased with the increasing of NaCl concentration. The comprehensive evaluation showed that Xinmu No.1 was the most salttolerant, and Aohan was the weakest salttolerant.
In order to achieve embryogenic callus induction and plant regeneration, the sterilized mature seeds of zoysiagrass (Zoysia japonica Stend.) were used as explants. The results indicated that peeled seeds after pretreatment in MS containing 2.0 mg/L 2,4D could successfully induce callus, the frequency was as high as 87.1%. In the course of subculture, there were four different types of callus. 1/2 MS containing 0.4 mg/L KT, or 1/2 MS containing 1.0 mg/L KT and 1.0 mg/L NAA was able to promote the differentiation of embryogenic callus effectively, the differentiation rate was 63.8% and 66.0%, respectively.
Total 202 325 Sorghum bicolor ESTs were downloaded from NCBI EST database. 6 663 SSRs loci within 5 661 ESTs were found out, and the emergence frequency was 20.19%, with the average distribution frequency of 1/3.93 kb. 3 446 (66.3%) from 5 197 ESTs could be used to design primers. Trinucleotide repeat was found to be the dominant type and GGC/GCC were the most frequent motifs in sorghum ESTSSRs. 20 pairs of primers were selected to design. Using sudangrass 722 and sorghum TX623A as templates, all the designed primers could be used to amplify the target sequences, and the usable rate was 100%, in which 4 pairs of primers were discrepant, and the polymorphism rate was 20%. Our results indicated that it was an effective and feasible approach to develop SSR markers based on sorghum ESTs.
The study overviewed the research and utilization status of Italian ryegrass （Lolium multiflorum）abroad, and the main production modes of planting L. multiflorum in winter paddy field of southern agriculture region in China. Italian ryegrass was mainly used for the production of cattle and dairy cow; it was also used for the biologic recovery of phosphor polluted soil abroad. In China, by nearly twenty years generalization, the techniques of winter cropping of Italian ryegrass has become a representative ecological agriculture mode of south China. The utilization modes of RiceItalian ryegrassDairy cow, RiceItalian ryegrassMeat goose, RiceItalian ryegrassPig, etc. have been well developed. The main limitation factors on further generalization of feeding herbivorous livestock and poultry with Italian ryegrass and needed research aspects were discussed.
The research results on chemical hybridizing agent were summarized, which included the mechanism and existing problems of chemical hybridizing agent and its application possibility in forage hybridization breeding. The developing of chemical hybridizing agent experienced three stages such as research on growth regulator induced male sterility, exploitation new chemical hybridizing agent compounds and application of chemical hybridizing agent in plant breeding. The mechanism of chemical hybridizing agent was not very clear at present, the information showed that EXP of chemical hybridizing agent could restrain the synthesis of branchedchain amino acids valine, leucine and isoleucine in vivo of rape, finally lead to male sterility. SC2053, BAU2, GENESIS could induce male sterility by declining pollen viability on wheat, decreasing anther proline content and enzymic activity and so on. Chemical hybridizing agent had few applications on the forage breeding, they mainly focused on the discussion of the emasculation effective, however few study were about getting the forage hybrid seeds by this method.
Present research studied the relationship between arable land and grain production in China through analyzing arable land protection and food security. The results showed that arable land significantly correlated with grain production, which means arable land is fundamental to ensure food selfsufficiency and food security in China; the principle theory between arable land protection and food security was analyzed based on Karldor Hicks Principle, and we thought that relieving arable land press was the key to ensure sustainable food production; to ensure the food security for the future China, the quantity and quality of arable land should be protected and improved.
Two dairy cows fitted with rumen cannulas were selected to study the effect of baled ensiling, concentrate to forage ratio (C/F), and moisture content on rumen degradibility characteristics of total mixed ration (TMR) using rumen nylon bag method. The results showed that baled ensiling increased dry matter (DM),crude protein (CP) and neutral degradation fiber (NDF) rumen disappearance and effective degradability of TMR (P0.05). Rumen disappearance rate and effective degradability of DM and CP increased with concentrate content of TMR increasing (P0.05).Compared with 40% and 50% moisture groups, effective degradability of CP were higher (P0.05) in 60% moisture, while no difference was observed between 40% and 50% moisture groups. It indicated that the baled ensiling could increase rumen disappearance and effective degradability of TMR nutrients（P0.05）.Along with the increase of C/F, rumen nutrient disappearance and effective degradability increased（P0.05）, and the effects of moisture content were varied on rumen disappearance and effective degradability of different TMR nutrients.
In order to utilize the debris and juice from alfalfa deep processing, their fermentation condition was studied. The results showed that it was easier for juice fermentation than debris; the fermentation could be accelerated by adding glucose and fermentation juice. But if the glucose concentration was higher than 2%, it had no obvious effect. The optimum concentration for juice and debris fermentation was 1% and 2% respectively. Increase of the temperature could improve fermentation, and the most suitable fermentation temperature was 35 ℃. For the 3 developmental stages (branching stage, blooming stage and podbearing stage) of alfalfa for fermentation, podbearing stage was the best.
To study the effect of broccoli residues on the egg quality, fertility and hatchability of Xianju San Huang layers, 384 chickens were randomly allocated to 4 treatments, which were the control group, groupⅠ, groupⅡ, and group Ⅲ, each treatment included 3 replicates of 32 chickens per replicate. They were respectively fed dietary broccoli residues at the level of 0%, 4%, 6% and 8%. The results showed that:1) There were no significant differences in the production performance for layers of adding broccoli residues （P0.05）;2) Compared with the control group, test group significantly improved in the albumen height, yolk color, haugh unit, eggshell thickness and eggshell strength (P0.05). And there were lower content of yolk cholesterol in the test Ⅱ and test Ⅲ (P0.05); 3) The fertility of test I and test Ⅱ was higher than the control (P0.05), but there were no significant differences between test Ⅲ and the control（P0.05）.The hatchability of test group was lower than the control, especially in the test Ⅱ and test Ⅲ (P0.05). It is suggested that adding broccoli residues could improve egg quality, decrease the content of yolk cholesterol, and increase fertility rate. However, the hatchability would fall with the increase of broccoli residues in feed.
Matrine, a new type of biological control agent extracted from the root, stem, leaf and fruit of Sophora flavescens, was used to study its effect on the control of grasshopper in desert grassland. Two experimental groups were designed with 1% of matrine extract and 4.5% cypermethrin and totally 6 treatments (1% matrine 225 mL/hm2, 300 mL/hm2 and 450 mL/hm2; 4.5% cypermethrin 450 mL/hm2, 600 mL/hm2 and 750 mL/hm2) were used. The results showed that 3 concentrations of 1% matrine showed control effect. The treatment of 1% matrine at dose of 450 mL/hm2 showed no difference with the treatment of 4.5% cypermethrin at doses of 450 mL/hm2 and 600 mL/hm2. So, the matrine should be the toppriority for the grasshopper control because of its environmental safety.