Search

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The paper aimed to gain an in-depth understanding of soil nutrient characteristics and fertilizer supply capacity in the main distribution areas of temperate climate types in Yunnan province, to facilitate scientific guidance on fertilization and to ensure steady improvement in the level of soil fertility and stable crop yield. (Method) From 2019 to 2022, 1880 topsoil samples were collected from the northwest, northeast, and central northern regions in Yunnan province, which were the main temperate climate types, in order to analyze the current status of soil nutrient and fertility, and to clarify the spatial distribution of and differences in soil nutrients in the main distribution areas of the climate types. (Result) The soil organic matter, total nitrogen, available phosphorus and available potassium all belonged to the rich level or above in the main distribution areas of temperate climate type in Yunnan province, with average contents of 39.86 g/kg, 2.09 g/kg, 29. 17 mg/kg and 166.31 mg/kg, and the proportion of the rich level or above were 66.85%,73.19%,54.11% and 40.25%, respectively. There was a good linear positive correlation between soil organic matter content and total nitrogen content, and soil nutrient changing trends among different soil types were similar. Brown soil had the highest organic matter and total nitrogen content, followed by yellow brown soil, paddy soil, while purple soil and dry red soil had lower levels. The total nitrogen, available phosphorus, available potassium, slowly available potassium, and pH in soil of cultivated land in the northwest region in Yunnan province were significantly higher than those in northeastern and north-central Yunnan (P<0.05), and the contents of total nitrogen, available potassium and slowly available potassium in soil in the central-north region were also significantly higher than those in the northeastern region in Yunnan province. The soil available potassium in the northeastern and central northern regions in Yunnan province was deficient, with a deficiency ratio of 36.99% and 45.69%, respectively. (Conclusion】 It was necessary to pay attention to balance fertilization in the northwest regions in Yunnan province to ensure the balanced absorption and utilization of nutrients by crops. Organic fertilizer should be increased in the northeast and central northern regions in Yunnan province, and potassium fertilizer should be appropriately increased according to crop types to steadily improve the soil fertility of cultivated land and crop yield. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to improve the effect of straw returning in sandy soil in the old Yellow River course region, thereby improving soil quality and crop yield.【Method】The effect of nitrogen (N), organic fertilizer (M), microbial agent (B), organic fertilizer + microbial agent (MB), soil enzyme agent (S), organic fertilizer + microbial agent + soil plant enzyme agent (MBS) on soil nutrients and crop yields was studied and compared based on the technique of straw-activated returning.【Result】The technique of straw-activated returning by adding exogenous materials could improve soil fertility and crop yield. The effect of N treatment on soil nutrient content and crop yield was no significant when N application was increased by 187.5 kg/hm². Compared with non-exogenous material (CK) treatment, MB treatment could increase soil organic matter and nutrient content, and the crop yield was also increased significantly. MBS treatment could further increase the straw returning effect. Compared with CK treatment, the soil organic matter content of MBS was increased by 4.5%-10.3%, total nitrogen was increased by 18.3%-33.8%, available phosphorus was increased by 11.3% -25.5%, and available potassium was increased by 52.6%-99.6%; Compared with the other five treatments of exogenous application, the corn yield of MBS was increased by 3.0%-32.0%, soybean yield was increased by 0.5%-30.2%, and wheat yield was increased by 5.4%-14.3%. 【Conclusion】In all treatments, straw returning combined with organic fertilizer + biological agents + soil enzyme (MBS) additives have the best effect on improving soil nutrient content and crop yield. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The paper aimed to study the effects of biochar application on the quality of cured tobacco, soil mutrients and soil microbial community structure. (Method) A randomised block group field experiment was conducted using Yunyan 87 as the experimental mate rial. Four treatments were set up (SWT1: Conventional fertilization; SWT2: Conventional fertilization biochar 1500 kg/hm²; SWT3: Conventional fertilization + biochar 2250 kg/hm²; SWT4: Conventional fertilization biochar 3000 kg/hm²) to determine the chemical composition, sensory quality of cured tobacco and the soil nutrients, rhizosphere soil hacterial diversity of the cured tobacco at maturity. [Result] The application of biochar had no significant influence on the soil nutrients and chemical composition of cured tobacco. Compared with the SWTI treatment, the sensory quality of cured tobacco was significantly improved in all treatments of biochar application, among which SWT3 treat- ment showed the best performance with 13.85%,6.56%,10.87%,8.70%,4.62%,12.31% and 6.25% improvement in amma quality, aroma amount, concentration, strength, impurities, usage value, and total score, respectively. With the increase of biochar application rate, the bacterial richness (Chaol index), diversity (Shannon indes), total ASV number and unique ASV number in the rhizosphere soil of flue- cured tobacco showed a decreasing trend. Compared with SWT1 treatment, the difference in microbial community structure composition incre aed with the increase of biochar application rate. The dominant phyla of each treatment were Proteobacteria, Acidobacteria and Actinobacte ria, At the phylum classification level, there was no significant difference in the community structure composition among different treatments. The application of biochar increased the relative abundance of f Rhizobiaceae, g Allorhizobium, Neorhizobium, g Pararhizobium, g Rhizobium and other nitrogen fixing bacteria, as well as funcultured_Actinobacterium, f Burkholderiaceae, Pseudomonadaceae, o Pseudomonadale, g Pseudomonas, g Sphingopyxis, & Dyella, g Massilin and other growth promoting bacteria. The application of biochar decreased the relative abundance of denitrifying bacteria such as sunclassified_Anaerolinencrar and g unclassified Caulobacteracene. At the ASV classification level, AN was the dominant factor affecting the changes in soil bacterial community structure. [Conclusion] The application of biochar improve the sensory quality of cured tobacco leaves, with SWT3 treatment (2250 kg/hm²) performing the best. The application of biochar reduce thizosphere soil bacteria a-diversity, and increase the relative abundance of beneficial hacteria such as nitrogen fixing bacteria, growth promoting bacteria, and denitrifying bacteria in the thizosphere soil, which is beneficial for increasing soil nutrients and promoting plant growth. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Engineering is the property of Forest Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 The present paper aimed to explore the changes of physicochemical properties and soil enzyme activities that are closely related to the occurrence of continuous cropping obstacles after the application of exogenous Methyl jasmonate（MeJA）.【Method】The three-year continuous cropping soil and red cheek strawberry were used in this paper to study the changes of physicochemical properties and soil enzyme activities of strawberry rhizosphere soil after applying different concentrations（0, 10, 50, 100, 200, 500 μmol/L） of exogenous MeJA. Indicators such as soil nutrient content, soil pH, soil enzyme activity, fruit number per plant, and single fruit weight were investigated.【Result】 Compared with CK treatment without MeJA, the contents of organic matter, alkali hydrolyzable nitrogen, available phosphorus and potassium of strawberry rhizosphere soil treated with MeJA decreased in general, which mostly significant, whether in the seedling stage or the flowering and fruiting stage; The pH of MeJA treatment was higher than that of the control treatment, and reached a significant level at the seedling stage, with an increase range of 3.90%-5.58%; The activities of peroxidase, polyphenol oxidase, protease and urease of MeJA treatment were generally improved compared with the control treatment, and most of them reached a significant degree; Compared with CK, MeJA treatment significantly reduced the plant height of strawberry by 22.33%-27.19%, and increased the number of strawberries per plant, of which treatment with 100 μmol/L MeJA increased by 26.25%. The effects of different concentrations of MeJA on the single fruit weight of strawberry showed a trend of increasing first and then decreasing, and the specific order was 100>50>10>0>200>500 μmol/L. Compared with CK, treatments with 50 μmol/L and 100 μmol/L significantly increased by 4.02%-31.60%. After the application of exogenous methyl jasmonate, the changes of soil nutrients, pH and soil enzyme activities in strawberry rhizosphere showed a transition rule at 100 μmol/L or its adjacent concentration with the increase of MeJA concentration. 【Conclusion】 After the application of an appropriate amount of exogenous methyl jasmonate, the continuous cropping strawberry showed that the rhizosphere soil nutrients were more absorbed, the soil acidification degree was alleviated, and the soil enzyme activity increased, which increased the number of fruits per plant and the single fruit weight of strawberries. However, the above trend was reversed with increasing MeJA concentrations. The above findings were beneficial to guide the production practice to apply exogenous methyl jasmonate to improve the physicochemical properties and soil enzyme activities of continuous cropping strawberry rhizosphere soil, so as to promote plant growth and alleviate continuous cropping obstacles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Soil organic carbon (SOC) and nutrient content are not only the key indicators of soil quality health evaluation, but also the limiting factors for the sustainable development of alpine and high altitude ecosystems in the plateau. The present paper aimed to explore the current status and influencing factors of soil surface nutrients in alpine swamp meadow, and to determine the fertilizer supply capacity of the soil type. [Method) Taking the alpine swamp meadow soil at the southern foot of the Qilian Mountains as the research object, and referring to the China Second Soil Census Nutrient Grading Standard, selecting pH, organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK) for the depth of 0-10 and 0-20 cm soil carbon, nitrogen, phosphorus, potassium content and ecological stoichiometric characteristics were analyzed. [Result] The soil layers with 0-10 cm content of organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP) and available potassium (AK) higher than 10-20 cm, pH, total phosphorus (TP) content did not change significantly, total potassium (TK) content increased slightly. The ecological stoichiometric characteristics showed that the C/P and N/P of the 0-10 cm soil layer were higher than 10-20 cm, and the N/P was lower than that 10-20 cm soil layer. On the whole, the pH of the alpine swamp meadow soil was neutral-weakly acidic, and the rank sequence of soil nutrient content was organic carbon (SOC) total nitrogen (TN) ≈ available nitrogen (AN) > total phosphorus (TP) > total potassium (TK) > available potassium (AK) > available phosphorus (AP). The organic carbon (SOC), total nitrogen (TN) and available nitrogen (AN) were at the first level, belonging to the rich level; Total phosphorus (TP) was at the second level, belonging to the relatively rich level; Total potassium (TK) was at the third level, belonging to the middle level; Available potassium (AK) was at the fourth level, belonging to the relatively lack level; Available phosphorus (AP) was at the sixth level, belonging to the exigence level. [Conclusion] The decomposition and mineralization rate of organic matter in the 0-20 cm soil layer of alpine swamp meadow in the southern foot of Qilian Mountains is slow, organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) are abundant, and N and Pavailability is low. The research results provide references for soil health, quality evaluation and ecological restoration in the alpine region of the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】The present paper aimed to clarify the comprehensive soil fertility status of pitaya orchards in Hainan province, and the spatial distribution and changing trend of soil nutrients in pitaya orchards in Hainan province were analyzed and predicted by means of survey sampling and statistical methods, so as to provide the basis for scientific fertilization and soil management of pitaya orchards.【Method】60 soil samples were collected from pitaya orchards in the main producing areas of Hainan province.Soil pH, organic matter, available nitrogen, available phosphorus, available potassium, exchangeable calcium, exchangeable magnesium, available copper and available zinc were used as evaluation indicators.Inverse distance weight interpolation method（IDW） was used to analyze the spatial distribution of each index, and used the factor analysis method combined with IDW to evaluate and predict the comprehensive soil fertility of the pitaya orchards in the survey area.【Result】The orchard soil in the survey area was neutral and slightly acidic, and 50% of the soil samples, pH were lower than 6.5; The organic matter content was moderately low, and some areas of Ledong and Sanya were insufficient; The average value of alkaline hydrolysis nitrogen was only 79.17 mg/kg, and the soil in the survey area was relatively lack of alkali-hydrolyzable nitrogen; The content of available phosphorus and available potassium were both high, and the average available phosphorus was 119.06 mg/kg, far exceeding its environmental risk threshold（60 mg/kg）; Orchards in the survey area the content of trace elements in the soil was relatively abundant. The IDW prediction map showed that the content of trace elements in Dongfang and Lingshui was high, and the content of Ledong and Sanya was low; Based on the analysis of the comprehensive score IFI, the results of the comprehensive fertility prediction of pitaya orchards in the entire study area using IDW showed that the eastern part of the study area, the comprehensive soil fertility of the orchards in the eastern and western regions of the study area was relatively high, while the soil comprehensive fertility of the orchards in the central part of Ledong and Sanya was relatively low.【Conclusion】The pitaya orchards in Ledong and Sanya still need to increase the input of organic fertilizers or increase the application of lime to improve the soil pH and supplement the medium and trace elements; The orchards in the survey area need to increase the input of nitrogen fertilizer and control the application of phosphate fertilizer. [ABSTRACT FROM AUTHOR]

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objectives] This paper aimed to explore the effects of reasonable straw return on water quality, soil nutrients and enzyme activities in rice-shrimp fields under the rice-crayfish integrated breeding mode. [Methods] The field experiment was carried out in 2019, and four treatments were set up, including the straw was not returned to the field without nitrogen fertilizer (CK), and the amount of straw returned to the field is 1 500 kg·hm-2(S1N1), the amount of straw returned to the field was 3 500 kg·hm-2(S2N2), and the amount of straw returned to the field was 4 500 kg·hm-2(S3N3). Water quality, soil nutrients and soil enzyme activities were determined. [Results]The dissolved oxygen in water was 6.68-14.59 mg·L-1. The total phosphorus and active phosphorus contents in water increased in different straw returning treatments compared with CK treatment. After 95 d of straw returning, the nitrate nitrogen content in water decreased with the increase of straw returning; the contents of nitrite nitrogen and ammonia nitrogen in the water under different treatments decreased. After straw returning, the maximum increase of soil total phosphorus content was 36.86% under the treatment of S3N3. Soil ammonium nitrogen reached the peak after 30 d of straw returning, and soil nitrate nitrogen content increased with the increase of straw returning. The three straw returning treatments decreased the soil urease activity, but increased the soil alkaline phosphatase activity. After straw returning to the field, the soil sucrase activity of CK and S1N1 treatments increased slightly, the largest increase of soil sucrase activity was observed in S3N3 treatment (118.30%), which was significantly higher than other treatments. [Conclusions] Different straw returning treatments had no adverse effects on water quality, the treatment with the amount of straw returned to the field of 4 500 kg·hm-2 was better than other treatments in terms of soil nutrients and enzyme activity. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 This paper aimed to clarify the chronological change in nutrients and fertility of soils grown with tobacco in Honghe prefecture. 【Method】 Total of 296 and 881 tobacco-growing topsoil samples were collected in 2014 and 2018, respectively. Soil fertility indexes and nutrients variation characteristics were evaluated and analyzed based on fuzzy mathematical theory, t-test and multiple comparison.【Result】 Compared with 2014, the average value of soil organic matter, alkali-hydrolyzable nitrogen and available potassium increased by 2.81 g/kg, 9.61 mg/kg and 16.74 mg/kg, respectively, and soil available boron and exchangeable magnesium decreased by 0.22 mg/kg and 51.69 mg/kg in 2018, respectively. Judging from the variation characteristics of nutrient groups, the group with slightly alkaline (7.5-8.5), the group with very high content (>40 g/kg) of organic matter, the group with moderate content of soil alkaline hydrolyzable nitrogen (100-150 mg/kg), the group with very high content (>350 mg/kg) of available potassium and the group with very low content (<0.3 mg/kg) of soil available boron were significantly higher in 2018 than in 2014, increased by 47.83%, 80.59%, 12.21%, and 72.19%, and 38.84%, respectively. In 2018, the group with very low (<10 g/kg) of organic matter, the group with low (65-100 mg/kg) of soil alkaline hydrolyzable nitrogen, the group with very low (<10 mg/kg) of soil available phosphorus, the group with medium (0.50-1.0 mg/kg) of soil available boron and the group with very high content (>400 mg/kg) of exchangeable magnesium group decreased by 46.0%, 17.02%, 16.57%, 41.36% and 30.87% compared with 2014, respectively. The group with high and very high content of effective zinc reached 80.14% and 85.37% in 2014 and 2018, respectively; And the group with moderate and above exchangeable magnesium content was ranged from 76.05% to 83.54%. The soil organic matter and alkaline hydrolyzable nitrogen contributed the most to the soil fertility of tobacco-growing soil in 2014 and 2018, respectively. In 2018, the average value of soil fertility index for tobacco-growing soil was 0.49, and the coefficient of variation was 26.53%. The soil with lower, medium and higher soil fertility index accounted for 20.66%, 61.29% and 17.03%, respectively. Compared with 2014, the percentage of lower and higher soil fertility index increased by 3.43% and 0.13%, respectively, and the percentage of medium soil fertility index decreased by 1.88%. There was no difference between low and medium soil fertility in each county ( city) in 2014 and 2018, only the higher soil fertility grade in Mile city showed significantly higher in 2018 than that in 2014. 【Conclusion】 The overall fertility of tobacco-growing soil in Honghe prefecture was good and the variation was small. Soil organic matter and alkaline-hydrolyzable nitrogen content were the main factors affecting the soil fertility of tobacco-growing soil in Honghe prefecture. The soil showed high content of available zinc and exchangeable magnesium, abundant organic matter, alkali-hydrolyzable nitrogen, and available potassium, but lack of available boron content. It is recommended to increase the use of boron fertilizer and reasonably control the application of zinc and magnesium fertilizers. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangxi Normal University - Natural Science Edition is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to investigate the appropriate amount and tillage effect of straw-rotted organic fertilizer + vertical rotary tillage in tobacco production in Hunan's tobacco-rice rotation, with the aim of improving the soil environment of tobacco planting in Hunan and providing scientific basis for improving the quality and increasing the yield of tobacco. [ Method] The experiment used 7 treatments in randomized group design, Tl: no straw-rotted organic fertilizer + conventional tillage; T2: straw-rotted organic fertilizer 1150 kg/hm² + conventional tillage; T3: straw-rotted organic fertilizer 2300 kg/hm² + conventional tillage; T4: straw-rotted organic fertilizer 4600 kglhm2 + conventional tillage; TS: application of straw-rotted organic fertilizer 1150 kg/hm² + vertical rotary tillage ; T6: application of straw-rotted organic fertilizer 2300 kg!hm2 + vertical rotary tillage; T7: application of straw-rotted organic fertilizer 4600 kg/hm² + vertical rotary tillage. The effects of different treatments on soil nutrients, agronomic traits of tobacco plants, physical traits, appearance quality, chemical composition and economic traits of tobacco leaves after baking were studied by ANOV A and comprehensive evaluation. [ Result] The application of straw-rotted organic fertilizer + vertical rotary tillage significantly increased soil organic matter and fast-acting nutrient content, and the highest soil fertility level was achieved when the straw-rotted organic fertilizer was applied at 4600 kg/hm² . At the same level of organic fertilizer application, the treatment of organic fertilizer + vertical rotary tillage had higher soil nutrients, agronomic properties of tobacco plants, physical properties of post-baking tobacco leaves, appearance quality, chemical composition and economic properties than the treatment of organic fertilizer alone. Among them, the 17 treatment had the highest appearance quality and chemical compatibility scores, with an average increase of 19. 86%, 3. 70% and 11. 53%, 2. 78% compared with Tl and T4. The tobacco yield and production value of 17 treatment increased by 12. 85%, 8. 10% and 26. 84%, 10. 46% compared with Tl and T4. The rate of top quality tobacco increased by 13. 80 and 6. 71 percentage points compared with Tl and T4. [Conclusion ] The application of 4600 kg/hm² straw-rotted organic fertilizer + vertical rotary tillage was the best, and most beneficial to the production of high-quality tobacco in the tobacco-rice rotation area of Hunan. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01 ). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to determine the stable nutritional quality of sweet potato under which soil texture, and to determine the main soil nutrient factors that affect the nutritional quality. [Method] Collecting 60 plant samples of sweet potato variety Gaoxi-14 and 60 bags of non-rhizosphere soil samples, the soil texture, 8 soil physical and chemical indexes and 5 sweet potato nutritional quality indexes were determined and analyzed. [Result] The coefficient of variation of the nutritional quality indicators of sweet potato, including amylose, amylopectin, total starch, soluble sugar and protein, was smaller in clay loam and loam, and larger in clay soil. Sweet potato amylose in loam was mainly negatively affected by pH, and the soluble sugar content was significantly higher than that in clay. Sweet potato amylose and amylopectin in clay loam were mainly affected by ammonium nitrogen positively and negatively. Sweet potato amylose and amylopectin in clay were mainly negatively affected by organic matter. [Conclusion] Loam soil and low pH are beneficial to produce stable quality and high amylose sweet potatoes, clay loam and high ammonium nitrogen are beneficial to produce stable quality and high amylose sweet potatoes, clay loam and low ammonium nitrogen are beneficial to produce stable quality and high branched chains starchy sweet potato. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the suitable straw returning methods for grain production in the Zitong River Basin. [Method] The impacts of straw non-returning (BR), straw mulching (FR), straw burying (MR) and straw heap back to field (DR) on soil fertility and grain production were investigated. [Result] Total nitrogen, available phosphorous and organic matter contents treated with FR, MR and DR increased by 18. 6 -38. 2 mg/kg, 5. 6 - 6 . 5 mg/kg, 0. 6 -2. 3 g/kg compared to BR treatment, respectively. The yield of rice, wheat, reap and corn increased by (1. 1 - 1. 3) x 10³, (0. 7 - 0. 8) x 10³, (0. 3 - 0. 5) x 10³, (0. 7 - 1. 0) x 10³ kg/hm², respectively. Returning straw to the field has significant effects on soil nutrients and grain yield. The contents of total nitrogen, available phosphorous and organic matter in DR treatment were significantly higher than FR and MR treatment, and the yield was slightly higher than FR and MR treatment. Rice, rape and corn all achieved the greatest economic benefits under DR treatment, with an average increase of 15. 6%, 27. 2%, 32. 1% compared with FR and MR, respectively. That of wheat on FR and FR was the same, 26. 7% higher than MR treatment. [Conclusion] Comprehensive analysis of the effect of soil fertility in the cultivated, grain yield and economic benefits, heap back to field is more conducive to the fertilization and grain production of the rice, rape and corn fields in the Zitong River Basin, and the straw mulching and heap back to field are both beneficial to the small grain production in the wheat field. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to study the effects of the application of the different weight that unfermented maize straw and fermented maize straw mangle returned to tobacco-planting soil on the change of soil humus composition, pH, soil available nutrients and the tobacco production value, which provided the scientific basis for the method of straw residue returned. [Method] This experiment was set up five treatment, CK :Control ( only use specific tobacco fertilizers), T1 :Specific tobacco fertilizers + 40 kg/667m² unfermented maize straw T2 Specific tobacco fertilizers + 80 kg/667m² unfermented maize straw,T3 :Specific tobacco fertilizers + 40 kg/667m² fermented maize straw, T4: Specific tobacco fertilizers + 80 kg/667m² fermented maize straw. It was the time to collect the soil samples, at the first day, the 30th day, the 60th day and the 90th day, after tobacco seedlings were transplanted, and the output value and yield were statistics of various treatments. [Result] During the period from first day to the 90th day, the available nutrients of experimental group was a increasing trend compared with the CK treatment. The HA/FA value of T3 and T4 treated showed a trend of that decreasing first and then increasing. [Conclusion] The HA (Humic Acid) /FA (Fulvic Acid) value of the soil could be effectively reduced by fermented maize straw mangle, and the average price and output value of roasted tobacco were significantly increased. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to under stand the status of soil nutrient abundance and deficiency in Honghe tobacco-growing area. [Method] 881 tobacco-growing soil samples were collected from different counties (cities) in Honghe tobacco-growing area, and 6 soil nutrient indicators were determined and analyzed. [ Result] The results showed that the average pH value of tobacco-growing soils in 7 counties( cities) was within the suitable growth range of flue-cured tobacco (5. 5 -7. 0), except Shiping county, which was slightly lower. Except for Jianshui ( 23, 66 g/kg) county and Luxi county ( 24. 93g/kg), the average content of organic matter in tobacco-growing soils in other counties( cities) was higher than that in suitable tobacco-growing aoils ( 1S -25 g/kg). The highest proportion of low content of alkali-hydrolyzed nitrogen (AN < 100 mg/kg) was Jianshui county (52. 63 % ), the highest proportion of available phosphorus ( >40 mg/kg) was Shiping county ( 37. 95 % ), the lowest proportion of available phosphorus ( < 20 mg/kg) was Gejiu city ( 90. 47 % ), the highest proportion of excessive water-soluble chlorine ( > 45 mg/kg) was Jianshui county ( 6. 57 % ) . [ Conclusion] The soil nutrient fertility in Honghe tobacco growing area belongs to the middle and upper level, which was more suitable for flue-cured tobacco cultivation. It is suggested that tobacco- growing counties( cities) with slightly poor soil suitability should adjust the existing fertilization schemes according to tobacco leaf quality in order to improve soil nutrient status and tobacco leaf quality. [ABSTRACT FROM AUTHOR]

【Objective】Through the comparison of models, the present paper aimed to explore the influence of ’chninese milk vent Returning to the Field coupled with rice and fish symbiosis’ on the soil nutrients and yield of rice, and provided a scientific basis for efficient and high-quality rice production and sustainable development.【Method】In this experiment, four treatments including conventional rice planting as a control(CK), chninese milk vent Returning to the Field(ZD), rice and fish symbiosis(YD),chninese milk vent Returning to the Field coupled with rice and fish symbiosis(ZY), measuring, analysis and comparison of the contents of soil nutrients(organic matter,total nitrogen, total phosphorus,total potassium and their effective state), rice yield and yield component index of each treatment were performed.【Result】Compared with CK, YD, ZD and ZY can effectively improve the soil fertility of rice in the current season, and ZY has the best effect. Compared with CK, soil organic matter, total nitrogen, total phosphorus, total potassium and their effective state content of ZY mature period were increased by 16.40 %, 18.18 %, 20.63 %, 3.42 %, 7.71 %, 15.96 % and 1.85 %(P<0.05); ZD can effectively alleviate soil acidification, and the soil pH at maturity was 6.06,which compared with CK, YD and ZY, it increased by 0.04, 0.12 and 0.08 units, and the difference was significant(P <0.05);Compared with CK,ZY, ZD, and YD can increase the yield of rice in the season effectively, and ZY has the highest yield of rice, reaching 6.29 t/hm~2. Compared with CK, ZD and YD, the actual yield of ZY increased by 4.83 %-11.33 %,and the difference was significant(P <0.05).【Conclusion】In summary, chinese milk vent returning to the field coupled with rice and fish symbiosis can effectively improve soil fertility and significantly increase rice production in the current season, which was an greenand efficient way of fertilizing. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to understand the influence of planting years on the soil fertility characteristics of wine vine-yards at the eastern foot of Ilelan mountain in Ningxia, and to provide a basis for the sustainable development of wine industry. [Method] vineyard rhizosphere soil and non-rhizosphere soil of 3 years,8 years and 20 years were collected from Ganchengzi district of Qingtongxia city at the eastern foot of Helan mountain in Ningxia, and soil fertility variation characteristics were measured. [Result] The pH value and electrical conductivity of grape rhizosphere soil were higher than that of non-rhizosphere soil regardless of the planting years. The total N, total K, organic carbon and available K in grape soil were increasing first and then decreasing under different planting years. The average content of total N, total K, organic; carbon and available K were the highest at 8 years. The content of alkaline N, available F and total P in grape soil increased with the planting years. There was no significant difference in microbial biomass C, N and P in grape rhizosphere soil and non-rhizosphere soil between 3 years and 20 years. [Conclusion] With the increase of planting years, nutrient enrichment rate in root zone was weaker and weaker, but the soil fertility was accumulated in the vineyard with the planting years. [ABSTRACT FROM AUTHOR]

【Objective】The objective of the paper is to provide a reference for soil nutrient management and sustainable operation in Karst areas.【Method】The soil samples were collected from woodland and dry land in Baiduo Village(dolomite areas) and Shiqiao Village(limestone areas) in Shibing County,Guizhou Province,and then the soil nutrient was analyzed.【Result】The soil developed from dolomite was featured with higher organic matters,total N,available P,available K and hydrolysable N.The soil developed from limestone was featured with higher total P and total K.Total N was positively and very significantly related to hydrolysable N and organic carbon in soil developed from limestone and dolomite.Hydrolysable N was positively and significantly related to organic carbon in limestone areas.Hydrolysable N was positively and very significantly related to organic carbon in dolomite areas.Land use patterns had obvious effects on nutrient content in soil developed from limestone and dolomite.Soil total K,total N,hydrolysable N and organic carbon content in limestone woodland was higher than dry land,and available K,total P,available P and pH was lower than dry land.Soil total P and available P in dolomite woodland are lower than dry land,and other indexes are higher than dry land.The organic matter,total N,total P and total K content in dolomite-developed soil was Grade II,Grade I,Grade VI and Grade III respectively.The organic matter,total N,total P and total K content in limestone-developed soil was Grade II,Grade I,Grade V and Grade I separately.【Conclusion】Soil nutrient was not only affected by soil forming rock,but also affected by land use pattern. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to find out the soil nutrients characteristics of spatial distribution in the roots of Haloxylon ammodendron in the southern margin of the Gurbantunggut Desert.【Method】The 149-Regimen,Ganjiahu Nature Reserve and the H.ammodendron in the desert area around the Karamay Agricultural Technology Development Zone were taken as examples,The spatial distribution and characteristics of pH,electrical conductivity,water content,organic matter and available phosphorus in the roots of H.ammodendron were quantitatively studied by a combination of field survey sampling and laboratory test analysis.【Result】In different areas,the soil water content and soil pH of the root ofH.ammodendron were mainly near the main root the middle of the crown>the edge of the crown,and the difference was significant(P <0.05); The organic matter content decreased with the depth of the soil layer; The soil available phosphorus content and the soil electrical conductivity were generally in the middle of the crown > near the main root > the crown edge,which generally decreases with the increase of soil depth.【Conclusion】There was a ‘fat island’ effect in the root zone of H.ammodendron in different regions,and the maximum concentration range in 0-40 cm soil layer. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective】 The objective of the paper is to explore the response mechanismof soil nutrients in economic fruit woodland to different intercropping and mono-cropping patterns in rocky desertification control area and to provide the scientific basis for vegetation optimization and soil nutrient supply of economic fruit woodland (Rosa roxburgMi and Juglans reiiia) in rocky desertification control area. ' Method】 The resjDonse of soil nutrients in economic fruit woodland to cropping patems in rocky desertification control area was stiadied by single-factor vari¬ance ，factor and sort-l)ased analysis combined witli fiel(d sampling and conventional soil nutrient analysis. ' Result】 The content of soil nutri¬ents showed a decreasing trend but soil pHincreased with increase of soil depth. Total N，total P，available P and available K content in soil withi diferent depth under Rosa roxburghii-Juglans reigia intercropping patem were higher than that under Rosa roxburghii mono-cropping pattern significantly (%<0. 05) . Total Kand available N content of soil with different depth under Roa rxburg"i mono-cropping pattern were higher thian that under Rosa roxburghii-Juglans reigia intercropping patern significantly (% <0. 05). Organic matter content of soil with 0-10 cm depth under Rosa roxburghii-Juglans reigia intercropping patern was higher than that under Rosa roxburghii mono-cropping patern but organic matter content of soil with > 10 cm depth under Rosa roxburghii-Juglans reigia intercropping patern was lower than that under Rosa roxburghii mono-cropping patem signiicantly (% <0. 05). The soil nutrient supply level under Rosa roxburghii-Juglans reigia inter¬ cropping patem (0.572) was higher thian under Rosa roxburghii mono-cropping patern (0. 439). Total K，organic matter，available N available K were main factors influencing soil nutrient supply level in the research area. ' Conclusion 】The response of soil nutrients in economic friait woodland to intercropping and mono¬cropping patems is sensitive in rocky desertification control area. The Rosa roxburghii-Juglans re^gia intercropping pattern and Roa roburghh mono-cropping pattern can consolidate and maintain the supply level of soil nutrient content in intercrop¬ping woodland and supplement soil nutrients in mono-cropping woodland for improving its supply level. [ABSTRACT FROM AUTHOR]

Studying the spatial variability and its affecting factors of surface soil organic matter and total nutrients can provide reference for soil management in the ecological fragile zone of the Loess Plateau. Based on the 93 soil sampling points in Wangdonggou watershed, this paper used a variety of geostatistical methods to analyze the spatial variability and its influencing factors of soil nutrients in the gully region of the Loess Plateau. The results showed that soil nutrient contents in the study area were at a moderate level. The spatial variability was in the following order: Total phosphorus > total nitrogen > organic matter > total potassium, and they were dominated by structural factors. Compared with total phosphorus and total potassium, organic matter and total nitrogen had smaller variation scale, weaker spatial autocorrelation and higher spatial complexity. Soil organic matter and total nitrogen presented a distribution pattern of high in the south and low in the north, and their main influencing factors included elevation, slope, curvature and land use. Total phosphorus was opposite to the former two, namely high in the north and low in the south. Elevation, slope, land use, soil mechanical composition and human activity had great influence on it. Total potassium was high in the center and low in the periphery, and its distribution was relatively scattered, and aspect and soil mechanical composition had a stronger effect on it. In view of the above results, regression prediction models between nine environmental factors and soil nutrients were established to provide data support for the sustainable use of soil resources in the study area. [ABSTRACT FROM AUTHOR]

This paper studies and discusses the changes of soil chemical indexes in different recovery years of XingJ an larch forest in Daxinganling, Inner Mongolia, in order to evaluate the self recovery of natural forest and provide basis for the management of Daxin- ganling forest in Inner Mongolia. The pH, C content, whole nitrogen, whole phosphorus and whole potassium content of the soil used in the experiment were calculated according to the Forest Soil Experiment Tutorial and the Soil Agroization Analysis. The effects of logging interference on the chemical properties of soil were studied using a single - factor variance ( ANOVA) analysis ( SPPS 13. 0 software). Results showed that ： ® comparing the differences in soil pH, soil C and other nutrients in Xing * an larch natural forest and two differ¬ent interference plots of clear cut and gradual cut, it is found that clear cut and gradual cut have significant differences in soil chemical properties (P<0.05). Clear cut has an extreme significant positive correlation with soil total nitrogen (P<0.01) , and a significant positive correlation with soil carbon content and pH ( P < 0. 05 ). (2) Comparing the significance of different cutting methods on soil physical and chemical properties in different years, there is a certain gap between the logging sites in 1987 and 2014, while the differ¬ences between the logging sites in 2009, 1987 and 2014 are not significant. Conclusion ： deforestation interference can reduce the pH of soil, objectively increase soil nutrients, and may be conducive to the natural renewal of forests. Logging interference significantly af¬fects the balance of soil carbon and other nutrients [ABSTRACT FROM AUTHOR]

[Objective]To some extent, the dominant functional traits determined the change of ecosystem function, which was the mass ratio hypothesis. [Method] In this paper, based on the mass ratio hypothesis, the effects of five functional traits of dominant species on ecosystem function in Li mountain meadow were studied by linear fitting and stepwise regression analysis. [Result] Except that the dominant species height had no significant relationship with soil organic carbon(P >0.050) , the dominant species leal area, specific leal area and height had significant linear relationship with community productivity and soil nutrients( P <0. 050) , while the dominant species leaf dry matter content and branch number had no significant linear relationship with community productivity and soil nutrients(P >0. 050). The stepwise regression analysis of five dominant functional traits and ecosystem function showed that the dominant species height was the main functional trait affecting community productivity, and the dominant species leaf area was the main functional trait affecting soil nutrients. [Conclusion ]The mass ratio hypothesis has a certain applicability in mountain meadow, but it is affected by the type of functional traits. Therefore, in the process of community management and ecosystem stability, it is suggested that the role of dominant species can be emphasized. [ABSTRACT FROM AUTHOR]

[Objective] The aim of this paper is to fully understand the temporal and spatial variation of soil nutrient in the cultivated land in Kunming district. [Method] Based on the analysis of 3907 farmland soil samples collected from 7 counties in Dianehi district of Kunming city, combined with ‘3S’ technology, the spatial distribution and change of soil nutrient content of farmland in Kunming city were studied. [Result] The results showed that the area with medium available boron content in the cultivated land in Dianehi district of Kunming city accounted for 70.08%, and the area with deficient available boron content accounted for 28.29%. The area with medium available zinc content accounted for 63.18% . Most areas of other nutrients were rich or more abundant. According to the average value of soil nutrient, the total nitrogen and alkali hvdrolysable nitrogen in the Dianehi district of Kunming city reached a rich level, while the organic matter, available phosphorus and available potassium were rich. Except for available boron, the average contents of effective manganese, effective zinc and effective molybdenum of trace elements were in high or higher level. The nutrient contents of vegetable land and seasonal vegetable land were higher than that of the dry land of fruit trees. [Conclusion]The total nutrient content of arable soil in Dianehi district of Kunming city is rich. Compared with the second national soil survey data, the contents of soil organic matter, total nitrogen, alkali hvdrolysable nitrogen, a-vailable phosphorus and available potassium are generally increasing. In the process of fertilization, it is necessary to combine the technology of improving the soil quality of cultivated land to achieve precise fertilization, and improve the utilization rale of fertilizer and the ability of soil fertilizer supply. [ABSTRACT FROM AUTHOR]

[Objective]The aim of this paper was to explore the distribution characteristics of soil nutrients in different recovery modes of rocky desertification control, and to provide scientific basis for further optimizing the vegetation allocation of rocky desertification control. [Method] Taking soil from five sampling sites as the study object, including Zanthoxylum bungeanum, Lonicera japonica, mixed forests, cardamom and abandoned farmland in Huajiang Rocky Desertification Control Demonstration Area in Guizhou. Soil layers of 0 - 10, 10 -20 and 20 -30 cm were sampled and monitored for 3 years before, during and after rainy season, and the distribution characteristics of soil nutrients under different recovery modes were analyzed. [Result] With the restoration of vegetation, compared with abandoned farmland, average values of soil bulk density, soil retention ability and capillary porosity in the four plots decreased respectively by 0.61 %, 7.97 % and 1.12 % , soil organic carbon, total nitrogen, total phosphorus and total potassium increased by 53.45 %, 45.72 %, 80.81 % and 1.44 % respectively, hydrolyzed nitrogen and available phosphorus increased by 53.36 % and 25.80 % , respectively. In the same plot, the contents of soil organic matter and soil nutrient contents were all shown as during rainy season > after rainy season > before rainy season. With the increase of depth of the soil layer, content of soil nutrients of different recovery models decreased, nutrients mainly concentrated in the surface layer. [Conclusion] There were differences in nutrient contents between different restoration models, and vegetation restoration in karst rocky desertification area had an ameliorative effect on ecological environment. [ABSTRACT FROM AUTHOR]

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Hippophae rhamnoides L. , an important vegetation type in Upper Min River, plays an important role in ecological protection and the restoration and reconst motion of degraded ecosystem in the region. The present paper was conducted to understand the effect of elevation on soil nutrient content and stoichiometric characteristics under H, rhamnoides shrubs. [Method] The total organic carbon, total nitrogen, total phosphorus were measured, and the C:P, C:N, N:P were determined along the altitude of 2450-3050 m and 2870 -3550 m in Miyaluo region and Chuanzhusi region. [ Result] (i) C, N and P increased gradually below 2900 m with the increase of altitude, and undulate changed above 2900 m in Miyaluo, while in Chuanzhusi, C, N, P fluctuating decline with elevation; ( ii) The change of C:N and C:P in the two regions was consistent with the changes of C, N and P, while N:P was only related to N in Chuanzhusi, it was not related to C and P with the change of altitude. ( iii) in H. rhamnoides shrubs soil, the C:N:P stoichiometry showed more total organic; carbon with relatively high C:N ratio, and relatively more phosphorus content with low N:P ratio; [Conclusion] The difference of nutrients with altitude in H. rhamnoides shrubs soil was related to the difference of precipitation, temperature and vegetation in different regions. Nitrogen might be an important limiting factor, thus the nitrogen fixation by Rhizobium in the root of H. rhamnoides was an important supplement to the soil nitrogen source in the forest. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to understand the fertility status of different types of tobacco planting soils in Honghe Prefecture. [Method] 888 soil samples were collected from different types of tobacco planting soils in Honghe Prefecture. [Result] The results showed that the average pH of the six types of soils except yellow soil was slightly lower, the of soil pH other types was all within the suitable growth range of flue-cured tobacco; the average content of organic matter except clay soil was higher than that of suitable organic matter content; the highest average content of alkali-hydrolyzed nitrogen was yellow soil, which reached 162.67 mg/kg. The average content of alkali-hydrolyzed nitrogen was the lowest in clay soil (106.37 mg/kg); the average content of available phosphorus was at middle level except yellow soil, the highest was sandy loam soil (39.60 mg/kg); the lowest was red soil (23.03 mg/kg); The average content of available potassium was the highest in red soil (230.50 mg/kg); the other types of soil was at the middle level, and the lowest in yellow soil (160.89 mg/kg). The content of water-soluble chlorine was highest in yellow soil, and the lowest in clay soil. Available zinc content of six types soils could meet the needs of high-quality flue-cured tobacco production, available boron content was lower than the critical value, available molybdenum content was higher than the critical value, but the proportion of available molybdenum content in other five types of soils was higher than the critical value except yellow soil. [Conclusion] Overall, alkaline fertilizer should be applied to improve the acidic yellow soil in Honghe tobacco-growing area, organic matter and alkaline hydrolyzable nitrogen content in clay soil was low, organic fertilizer and nitrogen fertilizer should be supplemented, chlorine-containing fertilizer should be forbidden in yellow soil with high water-soluble chlorine content, and available boron and molybdenum in six types of soils was generally low, so which should be increased. [ABSTRACT FROM AUTHOR]

[Objective] The present paper was conducted to popularize the natural herbage among vineyards in the eastern foothill of Helan Mountain. [Method] In this experiment, natural herbage for 1 year and cleared vineyard were taken as contrast. The effects of natural herbage on soil nutrients, enzyme activity and microorganism in different soil layers of vineyard were studied in Yunhao winery of Lanshan, Jins-han, eastern foothill of Helan Mountain. [Result] The soil alkali-hydrolyzed nitrogen and available phosphorus content were higher than that of the control, however, the pH, total salt, total nitrogen, total phosphorus, available potassium and organic matter content decreased, the number of bacteria, fungi and actinomycetes in different soil layers of natural herbage for 1 year vineyard soil increased,and the deep soil layer (40 -60 cm) was more obvious than the surface soil layer (0-20 cm), and natural herbage for 1 year could improve urease, sucrase and catalase in vineyard, especially for the surface soil layer (0 -20 cm), and the increase of soil enzyme activity was more obvious. [Conclusion]The natural herbage in vineyard can improve the soil condition to some extent, reducing soil pH, decreasing soil salt content, increasing soil microorganism and improving soil enzyme activity that provides a comfortable growth environment for grape growth, and then improves grape and wine quality, which is a good management method for vineyard soil in the eastern foothill of Helan mountain. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the soil nutrients and soil microbial activity of different tillage system in orchard. [Method] Field control experiment and laboratory analysis were conducted to study soil nutrients and microbial activities under different tillage system. [Result] Under different tillage system, soil pH was slightly acidic, and opposite volume weight, which showed no tillage > ploughed tillage > rotary tillage; Soil fertility (soil organic matter and total nitrogen) and available nutrients (available phosphorus, available nitrogen and available potassium) of different tillage system had the same variation trend which showed rotary tillage > ploughed tillage > no tillage, while there was no significantly difference of different tillage system in soil total phosphorus (P>0.05) ; Compared with no tillage, there was a significant increase in soil total microbial quantity and soil enzyme activity (invertase, dehydrogenase, urease and phosphatase), which ordered rotary tillage > ploughed tillage > no tillage under rotary tillage and ploughed tillage. Soil microbial activity was from 0. 38 to 0. 69 in order of rotary tillage > ploughed tillage > no tillage with the significant difference (P <0.05). [Conclusion] Overall, the soil microbial biomass carbon turnover rate was higher than the soil microbial biomass nitrogen turnover, which indicated that the microbial biomass carbon updated faster than microbial biomass nitrogen. [ABSTRACT FROM AUTHOR]

Copyright of Forest Engineering is the property of Forest Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】In order to provide scientific references for fragrant taro planting, reasonable fertilization and improvement of fragrant taro quality, the present paper studied soil profile and nutrient characteristics of fragrant taro. 【Method】Through field soil profile observation and laboratory test, the soil profile characteristics and nutrient content vertical distribution of fragrant taro were studied by SPSS software and Origin software. 【Result】(i) The soil thickness of 6 soil profiles was deep. The depth of the topsoil and the heartsoil was between 65 and101 cm, were all mature soil, the configuration includes the plough layer and plough pan, the redox deposition layer and the maternal layer, the topsoil was affected by artificial farming and forms the plough layer and plough pan, colors are mainly black and brown. The heartsoil was relatively stable, influenced by soil factors, the soil presents orange and red color. The structure respectably presents the obvious iron and manganese film;(ii) The particle composition was mainly composed of granules. The silt content was between 40 % and 67 %. The texture was mainly clay loam, silty loam and loam; The weathering of soil profile is not high, and the degree of weathering decreases with the depth of profile. The nutrients content of the 6 soil profiles decreased as the depth increased.【Conclusion】In the fragrant taro, the soil horizon is deep, the degree of weathering is not high and nutrient elements present the distribution of surface agglomeration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)