Effects of Organic Fertilizer on Fruit Quality and Acidified Soil Chemical Properties in Yantai Orchard

[Objective] This study aimed to investigate the improving effect of organic fertilizer on acidified soil as well as their effects on fruit quality and quantity in Yantai orchard.[Method] Plot experiment was conducted to investigate the effects of organic fertilizer on fruit yield and quality of Red Fuji and chemical properties of acidified soil.[Result] The apple yield in acidified soil applied with organic fertilizer all increased.Under the application of biological organic fertilizer,the apple yield was higher,and it was 8.92% higher than that in the control group.Under the mixed application of chemical fertilizer and biological organic fertilizer,the growth and development of apple trees were improved,and the total soluble solid(TSS) content,vitamin C(Vc) content and TSS-acid ratio in mature apples all increased.The application of organic fertilizer significantly reduced soil acidity.Compared with those in the control group,the soil p H value,organic matter content and alkali-hydrolyzable nitrogen content under the application of biological organic fertilizer were increased by 8.33%,15.10% and 30.80%,respectively.[Conclusion] The application of biological organic fertilizer could improve the yield of apple in acidified soil.

Effect of Balanced Application of Potash Fertilizer on the Yield of Rice Yongyou 15 and Soil Nutrient Content

By the field experiment,we set up the treatments of non-application of potash fertilizer,conventional fertilization,balanced fertilization and halved application of potash fertilizer,and studied the effect of different treatments on rice yield and soil nutrient content. The results showed that compared with non-application of potash fertilizer,conventional fertilization and balanced fertilization significantly increased the spike length,thousand kernel weight,yield and total potassium content of the stalk,as well as soil organic matter,total nitrogen and available phosphorus content; compared with conventional fertilization,the balanced fertilization did not significantly increase the rice growth and yield,but effectively increased rice grain total nitrogen,stalk total nitrogen and total phosphorus content,as well as soil available phosphorus and available potassium content. It could be found that potash fertilizer played a certain role in increasing rice yield and soil nutrient content,and the balanced fertilization had the most significant effect.

Effects of Oyster Shell Soil Amendmenton Fruit Auality and Soil Chemical Properties in Greenhouse Tomato Acidic Soils

[Objective]The aim was to explore the feasibility of applying oyster shell soil amendment for tomato production in order to determine proper quantity of the soil conditional.[Method]Field tests were performed to research effects of the soil conditioner on tomato yield,quality and soil p H.[Result]The results showed that tomato yield increased in the treatment groups with oyster shell soil amendment.The group SC50 increased the most by 16.5%than the control group.Based on normal fertilization,tomato growth was promoted by the soil amendment,and per tomato weight and lycopene content both improved during peak-fruiting period.Besides,soil p H value was enhanced by the soil amendment also.[Conclusion]It can be concluded that the effect was the best when soil conditioner was applied at 750 kg/hm2.

Effects of three types of soil amendments on yield and soil nitrogen balance of maize–wheat rotation system in the Hetao Irrigation Area, China

Excessive fertilization combined with unreasonable irrigation in farmland of the Hetao Irrigation Area(HIR), China, has resulted in a large amount of nitrogen(N) losses and agricultural non-point source pollution.Application of soil amendments has become one of the important strategies for reducing N losses of farmland.However, there is still no systematic study on the effects of various soil amendments on N losses in the HIR.In this study, three types of soil amendments(biochar, bentonite and polyacrylamide) were applied in a maize–wheat rotation system in the HIR during 2015–2017.Yields of maize and wheat, soil NH3 volatilization, N2O emission and NO3– leaching were determined and soil N balance was estimated.The results showed that applications of biochar, bentonite and polyacrylamide significantly increased yields of maize by 9.2%, 14.3% and 13.3%, respectively, and wheat by 9.2%, 16.6% and 12.3%, respectively, compared with the control(fertilization alone).Applications of biochar, bentonite and polyacrylamide significantly reduced soil N leaching by 23.1%, 35.5% and 27.1%, soil NH3-N volatilization by 34.8%, 52.7% and 37.8%, and soil N surplus by 23.9%, 37.4% and 30.6%, respectively.Applications of bentonite and polyacrylamide significantly reduced N2O-N emissions from soil by 37.3% and 35.8%, respectively, compared with the control.Compared with application of biochar, applications of bentonite and polyacrylamide increased yields of maize and wheat by 5.1% and 3.5%, respectively.Our results suggest that soil amendments(bentonite and polyacrylamide) can play important roles in reducing N losses and increasing yield for the maize–wheat rotation system in the HIR, China.

Effects of Mouse Thatched on Soil Temperature, Yield and Quality in Apple Orchard

[Objectives]This study was conducted to study the effect of mouse thatched on soil temperature,yield and quality in orchards.[Methods]The response of orchard soil,yield and quality to sod culture was studied by comparisons of grassing for two years,three years and clean cultivation.[Results]In April,the soil temperature in mouse thatched area was higher than that in clean cultivation area,and the temperature in the three years of sward was the highest.From May to July,the temperature in mouse thatched area was lower than that in clean cultivation area,and the temperature was lowest in the three years of sward.At the same time,the fruit yield and quality were improved.Averaged the two years,the yield of apple increased by 12%,and the contents of sugar,soluble solids and vitamin C and the firmness of the fruit were increased,and the total acid content was decreased by planting mouse thatched.[Conclusions]Adjusting soil temperature in orchards by planting grass achieved the effects of promoting the activity of microorganisms,facilitating the growth of root system,increasing the yield and improving the quality.

Spatial and Temporal Variability of Soil Organic Matters in Se-rich Areas of Hainan Island in Recent 30 Years

[Objectives] The aim was to reveal the distribution of soil organic matter content in cultivated land in the Se-rich areas of Hainan in 1980and 2010, so as to provide reference for the study on the evolution of soil organic matter content.[Methods] With the combination of field investigation with indoor analysis, the characteristics of organic matter content in the Se-rich areas of Hainan in 1980 and 2010 was revealed by means of spatial analysis, and the differences were analyzed.[Results] In the last 30 years, the proportion of 20-30 g/kg of soil organic matter content in the Se-rich areas of Hainan was reduced, but the content of soil organic matter in the area generally increased. The average value of the content of organic matter in the area was increased from 25.3 g/kg in the 1980s to 28.1 g/kg, but its spatial distribution was uneven.[Conclusions] The farmers should be guided to change the fertilization structure, and attention should be paid to the application of organic fertilizer, so as to improve the soil organic matter content.

Effects of Phosphate Fertilizer on Yield and Quality of Eleocharis dulcis

The effects of different application levels and species of phosphatic fertilizer on Eleocharis dulcis were studied. The results showed that the growth stage of Eleocharis dulcis was not significantly influenced by different levels of phosphatic fertilizer application, with phosphorus level in 195-375 kg/hm^2. With increasing of the phosphorus level, starch and total soluble sugar accumulated, but the yield was not improved significantly. The analysis on the economic benefits showed that the best phosphorus level was 195 kg/hm^2. The growth stage and yield of Eleocharis dulcis were not considerably influenced by different proportions of calcium-magnesia phosphate fertilizer and ammonium dihydrogen phosphate. With increasing of ammonium dihydrogen phosphate, big-fruit rate of Eleocharis dulcis kept growing, but the accumulations of starch and total soluble sugar were decreasing.

Hainan; Nandu River; Soil nutrient; Spatial distribution

[Objectives] Within a research area on basin scale, soil nutrient distribution characteristics and main causes were analyzed, to provide a basis for soil nutrient management on basin scale.[Methods] With the Nandu River Basin of Hainan Island as the research area, by means of geostatistics and spatial analysis methods, the distribution available of soil pH, organic matter, alkali-hydrolyzale nitrogen, available phosphorus, available potassium and available trace elements were studied.[Results] The cultivated land in the Nandu River Basin of Hainan Province is overall acidic, with an average pH of 5.2. The soil organic matter content is overall lower, and its spatial differences are also significant. Soil alkali-hydrolyzable nitrogen, exchangeable calcium and exchangeable magnesium content are at a medium level, but the soil lacks available phosphorus and available potassium.[Conclusions] The differences in pH within the research area might be related to parent materials distribution and fertilizer applications. The main reasons for the low soil organic matter content are inadequate and uneven input of organic fertilizer and high-temperate rainy climate. The lack of soil phosphorus and potassium is mainly caused by unreasonable fertilizer application and climatic and terrain factors.

Fertilization Status and Soil Nutrient Condition in Some Asparagus Production Regions of Zhejiang Province

Asparagus is delicious,with rich nutrition,and it is one of main economic crops in Zhejiang Province.In this paper,by investigating fertilization situations of farmers in several asparagus production regions(Fuyang,Pinghu,Changxing and Cixi) and soil nutrient condition of asparagus garden with different plantation years,fertilization status and nutrient condition of asparagus garden were described,and fertilization suggestion was proposed,which aimed to guide scientific fertilization of asparagus and promote healthy development of industry.

Distribution of Soil Nutrients in Se-rich Areas of Hainan Island

[Objectives] The aim was to reveal the distribution of soil nutrients in Se-rich area of Hainan and to clarify their specific contents, so as to provide references for the development of Se-rich area agriculture in Hainan.[Methods] With the se-rich area in Hainan as the object, field investigation and indoor analysis were combined to elucidate the nutrient status of cultivated soil in the area and analyze its nutrient distribution.[Results] The soil in the se-rich area in Hainan province was generally acidic with the average soil pH value of 5.0. The difference in soil pH between different landforms and different altitudes was not significant, ranging from 4.9 to 5.3. Soil available P and available K contents were low to intermediate, and the soil available N content was moderate. The farming system, chemical fertilizer application structure and meteorological factors were the main causes of the distribution of soil nutrient elements. The soil exchangeable calcium and magnesium content was rich, and the distribution of trace elements in the arable soil of different terrains and elevations was closely related to the distribution of soil parent material in the region. The increase of soil organic matter content in arable land could be achieved by increasing the application of organic fertilizer and guiding the farmers to enhance the application of straws to fields.[Conclusions] The application of soil N, P and K fertilizers should be combined with the application of soil organic fertilizers to improve the soil fertility of cultivated land.

Spatiotemporal Changes in Soil Nutrients:A Case Study in Taihu Region of China

The accurate assessment of the spatiotemporal changes in soil nutrients influenced by agricultural production provides the basis for development of management strategies to maintain soil fertility and balance soil nutrients. In this paper, we combined spatial measurements from 2 157 soil samples and geostatistical analysis to assess the spatiotemporal changes in soil organic carbon （SOC）, total nitrogen （TN）, available phosphorus （AP） and available potassium content （AK） from the first soil survey （in the 1980s） to the second soil survey （in the 2000s） in the Taihu region of Jiangsu Province in China. The results showed that average soil nutrients in three soil types all exhibited the increased levels in the 2000s （except for AK in the yellow brown soil）. The standard deviation of soil nutrient contents increased （except for TN in the paddy soil）. Agricultural production in the 20 years led to increases in SOC, TN, AP and AK by 74, 82, 89 and 65%, respectively, of the Taihu areas analyzed. From the 1980s to 2000s all the nugget/sill ratios of soil nutrients indices were between 25 and 75% （except for AK in the yellow brown soil in the 2000s）, indicating moderate spatial dependence. The ratio of AP in the yellow brown soil in the 2000s was 88.74%, showing weak spatial dependence. The spatial correlation range values for SOC, TN, AP and AK in the 2000s all decreased. The main areas showing declines in SOC, TN and AP were in the northwest. For AK, the main region with declining levels was in the east and middle of western areas. Apparently, the increase in soil nutrients in the Taihu region can be mainly attributed to the large increase in fertilizer inputs, change in crop systems and enhanced residues management since the 1980s. Future emphasis should be placed on avoiding excess fertilizer inputs and balancing the effects of the fertilizers in soils.

Effects of controlled-release urea application on the growth, yield and nitrogen recovery efficiency of cotton

Field experiments were conducted to study the effects of the controlled release urea (CRU) application on growth yield and nitrogen recovery efficiency of cotton in the main cotton zone of the Yangtze River basin in 2010. Different nitrogen levels were set in order to determine the suitable dosage of CRU on cotton. The special purpose was to provide evidence for the CRU application in cotton fields. The results show that the application of CRU promotes the growth of cotton significantly and enhances the nitrogen supply in the whole period. Compared to the treatment with total N as base fertilizer (UB), the bod, flower, little bolls and total bolls are increased significantly. There are no significant differences in the yield between the CRU treatment and the treatment of controlled release urea and urea combined application (60%CRU + 40%U), but an increase by 12.38%-22.67% compared to the UB treatment, and an increase by 4.49%-7.23% compared to the treatments of total N split application (UD). The nitrogen uptake of CRU treatment was significantly increased by 13.01%-48.32% and 30.27%-13.01% than UB treatment and UD treatment, respectively. The nutrient recovery efficiency of CRU treatment is increased by 16.42-20.59, 5.92-11.29 and 4.22-12.59 percentage points compared to the UB treatment, UD treatment and 60%CRU + 40%U treatment, respectively. In this study, there was a good linearity relationship between the cotton yield and amount of CRU in Wuxue site. The yield of cotton response to amount of CRU could be described by the model of linear plus plateau in Jingzhou site.

Cultivating New Agricultural Operators to Promote the Transformation and Upgrading of Traditional Agriculture——A Case Study of Nanchong City

In order to provide reference for cultivating new agricultural operators to promote the transformation and upgrading of traditional agriculture,the main practices,achievements and problems of cultivating new agricultural operators to promote the transformation and upgrading of traditional agriculture in Nanchong City,Sichuan Province were analyzed firstly,and then some measures were proposed.

Effect of Silicon Application on Rice Growth and Production Structure

This paper studies the effect of silicon on the growth and production structure of rice( Oryza sativa L.),and proposes the appropriate applying amount of silicon. The results show that the application of silicon fertilizer to rice can increase specific leaf weight and leaf area index,and improve rice yield by increasing grain number,kernel number and thousand kernel weight. The growth rate of rice yield is 3. 45%-15. 69% by applying silicon. In the Jianghan Plain,the applying amount of silicon fertilizer for rice( SiO_2) is recommended at 15-30 kg/ha.

Main Measures and Achievements in the Development of Organic Agriculture in Nanchong City

In order to improve the quality and efficiency of agriculture,increase farmers'income steadily and rapidly,and improve the ecological environment of agriculture,a strong city of organic agriculture should be constructed in Nanchong City.Based on ecological agriculture,Nanchong makes great efforts to build a strong city of organic agriculture,takes environmental protection supervision as an opportunity to promote sustainable agricultural development feasibly,takes regional brands as the starting point,and promotes the development of agricultural brand.The main measures and achievements of the development of organic agriculture in Nanchong City are analyzed and discussed starting with the next work plan.

The Evaluation Principles,Indicator System and Methods for Environment-friendly Utilization of County-level Land Resources

From the perspective of environmental issues concerning land use and importance of county,we analyze the great significance of environment-friendly use of county land resources. On the basis of discussing the concept and connotation of environment-friendly utilization of land resources,we build the basic framework for the evaluation of environment-friendly utilization of land resources from environment,economy and society,and propose the evaluation methods combining composite index method and multi-angle single indicator evaluation method. At the same time,we establish the grading system and grading standards for environment-friendly county land use,to promote the qualitative and quantitative evaluation of environment-friendly county land use.

The Remediation Mode for the Polluted Land in Inner Mongolia

This paper discusses the method of contaminated soil remediation technologies at home and abroad,analyzes the soil restoration situation in Inner Mongolia,and puts forward some suggestions on the development direction of soil repair industry for Inner Mongolia.The research methods of this article include literature review,summarization of data,comparison and analysis,and generalization and summarization.The soil restoration has made certain achievements in Inner Mongolia in recent years.But the technical level and policy level are still very imperfect,having not reached the national average.Some recommendations are proposed.The first is to improve soil repair local laws,regulations and technical standards.The second is to increase investment in scientific research in the field of soil restoration,and the introduction of new technology,to encourage independent innovation.The third is to fix soil combined with related industrial projects and avoid redundant construction.The last one is to intensify propaganda to improve public consciousness of the soil pollution prevention and control.

Investigation and Research on the Current Status of Fertilization in Facility Vegetables of Shandong Province

In order to clarify the current situation and main problems in facility vegetable fertilization and guide farmers to fertilize scientifically,an investigation on the yield and fertilization of facility vegetables( tomato,cucumber,eggplant and celery) was carried out in six districts and counties in Shandong Province from 2016 to 2017. The results showed that among the four vegetables,the yield levels of eggplant and celery varied slightly with the coefficient of variation between 7. 18% and 27. 63%,and the yield levels of tomato and cucumber varied greatly with the coefficient of variation between 33. 84% and 65. 15%. In terms of fertilization,the differences in N,P2O5 and K2O inputs in cucumber was the largest,and the maximum values of the nutrient inputs were 7. 95,8. 54 and 8. 77 times of the corresponding minimum values,respectively. The input amounts of N,P2O5 and K2O in tomato,cucumber and eggplant were 1. 47-2. 68,3. 93-7. 50 and1. 09-1. 51 times of the corresponding demands,respectively. The N and P2O5 inputs of celery exceeded the demands by 32. 00% and 79. 00%,respectively,while the K2O input was only 49. 00% of the demand. The ratios of N∶ P2O5∶ K2O input in the total application amount,organic fertilizer,base fertilizer and topdressing chemical fertilizer of facility vegetables were,respectively,1∶ 0. 84∶ 1. 02,1∶ 0. 84∶ 0. 80,1∶ 0. 99∶ 1. 05 and 1∶ 0. 77∶ 1. 25. The proportion of P2O5 input was too high,while the proportion of K2O input coming from the organic fertilizer was insufficient. The average proportions of organic fertilizer in N,P2O5 and K2O inputs were 43. 96%,43. 72% and 36. 99% respectively. The proportions of organic fertilizer in N and P2O5 inputs were reasonable,while that in K2O was lower.In N,P2O5 and K2O inputs of different vegetables,the proportions from organic fertilizer were reasonable in cucumber,higher in eggplant and lower in tomato and celery. The recommendations were presented in this paper that the inputs of N and P2O5 should be reduced,and the inputs of K2O and organic fertilizer should be increased,while farmers should choose fertilizer with low P2O5 and high K2O contents.

Integrated analysis of changes in soil microbiota and metabolites following long-term fertilization in a subtropical maize-wheat agroecosystem

Although the application of inorganic fertilizer is a widespread agronomic practice used to boost soil productivity and crop yields,the effects on soil microbiome and the metabolic mechanisms involved in the high-yield response of crops to long-term fertilization remain poorly described.In this study,combined metagenomic and metabolomic analyses were used to explore the mechanism of crop yield response to the 20-year application of nitrogen-phosphorus-potassium fertilizers in a subtropical agroecosystem in Southwest China.Soil bacterial and fungal communities were monitored using16S r RNA(bacteria)and internal transcribed spacer 1(ITS1)full-length gene(fungi)amplicon sequencing technologies,and metabolites were detected using a liquid chromatograph mass spectrometer.The results revealed that,in addition to providing nutrients,long-term fertilization shaped the compositions of bacteria and fungi to increase crop yields.Long-term fertilization significantly increased the relative abundances of plant growth-promoting rhizobacteria and arbuscular mycorrhizal fungi and promoted the secretion of soil metabolites such as carbohydrates,organic acids,and organic nitrogen compounds,which were primarily enriched in amino acid metabolism pathways.The increases in carbon and nitrogen sources and bioactive substances in soil promoted the increases in plant biomass and thereby maintained soil quality and production capacity.The findings highlighted the importance of soil metabolites in maintaining soil productivity as well as crop yields,and suggested that regulating key metabolites could increase crop yields in agroecosystems.

Crop rotation-dependent yield responses to fertilization in winter oilseed rape(Brassica napus L.)

Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed(RR) and cotton–rapeseed(CR) rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization,seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen(N)fertilization in the RR rotation were 96.6% and 6.56 kg kg- 1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus(P) and potassium(K) fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha- 1was recommended according to the economically optimal N fertilizer rate(EONFR). In contrast, the EONFR was 14 kg N ha- 1lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.