Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil

Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies.

Effect of Soil Fertility and Planting Density on the Partitioning of the Above-Ground Biomass of Eucalyptus in a Plantation (Pointe-Noire, Republic of Congo)

Afforestation and reforestation are useful approaches to improve carbon sequestration. With the advent of forest plantations, growing environment conditions have become increasingly restrictive for light, soil nutrients, and interactions between trees to acquire available resources. Tree biomass data are essential for understanding the forest carbon cycle and plant adaptations to the environment. The distribution of tree biomass depends on the sum of multiple stand conditions. The data are from a dedicated experiment with two very contrasting areas of fertility, and two planting densities, including a high density at planting in order to achieve thinning. The plant material consists of the high-performance clones of Eucalyptus urophylla × E. grandis and the reference clone E. PF1. We hypothesize that the distribution of biomass changes as the intensity of competition changes and that this is accelerated by the fertility of the sites in time. The results indicate that fertilization, planting density and clones have an impact on biomass partitioning.

Analysis of the Fertilizing and Bioremediation Potential of Leaf Litter Compost Amendment in Different Soils through Indexing Method

This research study explored the efficacy of leaf litter compost as a sustainable soil amendment with the objective of promoting soil health and mitigating the accumulation of potentially toxic elements. The investigation encompassed the impact of various organic compost amendments, including leaf compost, cow dung manure, kitchen waste compost, municipal organic waste compost, and vermicompost. The study employed Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to evaluate soil nutrient levels and concentrations of Potentially Toxic Elements (PTEs) such as arsenic, chromium, cadmium, mercury, lead, nickel, and lithium. The fertilization and bioremediation potential of these compost amendments are quantified using an indexing method. Results indicated a substantial increase in overall nutrient levels (carbon, nitrogen, phosphorus, potassium, and sulfur) in soils treated with leaf compost and other organic composts. Fertility indices (FI) are notably higher in compost-amended soils (ranging from 2.667 to 3.938) compared to those amended with chemical fertilizers (ranging from 2.250 to 2.813) across all soil samples. Furthermore, the mean concentrations of PTEs were significantly lower in soils treated with leaf compost and other organic compost amendments compared to those treated with chemical fertilizers amendments. The assessment through the indexing method revealed a high clean index (CI) for leaf compost amendment (ranging from 3.407 to 3.58), whereas the chemical fertilizer amendment exhibits a relatively lower CI (ranging from 2.78 to 3.20). Consequently, leaf compost and other organic composts exhibit the potential to enhance sustainable productivity, promoting soil health and environmental safety by improving nutrient levels and remediating potentially toxic elements in the soil.

Evaluation of Soil Fertility Quality and Environmental Driving Factors in Different Soil Types of Artificial Forests

The aim was to clarify the environmental driving factors of soil fertility indicators in artificial forests of Guangxi and comprehensively evaluate the soil fertility level.By collecting data on the current status of soil in artificial forests,the spatial distribution of major soil fertility indicators was analyzed,and the distribution map of the fertility index of artificial forests in the entire region and the comprehensive fertility index of artificial forests of different soil types were obtained.Canonical correspondence analysis method was used to analyze soil fertility indicators and environmental factors,and the environmental driving factors of soil fertility indicators for artificial forests of the main soil types in Guangxi were obtained.The results showed that over 90%of the soil fertility index of artificial forests in the entire region was between 0.20 and 0.50.The order of soil fertility index of different soil types of artificial forests from high to low was yellow brown soil>yellow red soil>yellow soil>red soil>limestone soil>latosolic red soil>laterite.In artificial forests of latosolic red soil,the correlation between soil alkaline nitrogen and organic matter,annual average temperature was high,while the correlation between soil available phosphorus and organic matter,pH was high,and the correlation between soil available potassium and environmental factors such as slope,altitude,rainfall,accumulated temperature,and slope aspect was high.In artificial forests of red soil,the correlation between soil alkaline nitrogen and slope,altitude was high,while the correlation between soil available phosphorus and accumulated temperature,rainfall was high,and the correlation between soil available potassium and pH was high.In artificial forests of limestone soil,there was a high correlation between soil alkaline nitrogen and slope,organic matter,a high correlation between soil available phosphorus and accumulated temperature,rainfall,and a high correlation between soil available potassium and pH.

Effect of Different Rates and Mixtures of Solid Household Waste and Faecal Sludge-Based Composts on Soil Fertility and Productivity of Sunflower (Helianthus annuus L.) in Dschang, West Cameroon

The unbalanced and inadequate use of fertilizers is one of the causes of soil degradation. Combined with the ever-increasing population, it is necessary to find sustainable agricultural production alternatives. The present work aims to determine the effect of different rates and mixtutes of organic amendments on soil fertility and the performance of Sunflower (Helianthus annuus L.). In the field, treatments consisted of solid household waste and faecal sludge in the ratios of 3/5 (V1), and a mixture of faecal sludge and household waste in the ratio of 3/5 with 900 worms (V2). At the end of the composting process, V1, V2 composts and the poultry manure (PM) were applied at rates of 4, 5 and 6 t∙ha−1 in a randomized complete block design with three replications. Soil samples were collected before and after the experiment and analyzed. The main results revealed that at the end of the composting process, there was a progressive improvement in the physico-chemical properties of V1 and V2 composts. In particular, the C/N ratio, phosphorus (P) and total nitrogen (TN) initially at 16.49 ± 0.42 (V1, V2), 21.06 ± 0.07 mg∙kg−1 (V1, V2), 0.76% ± 0.08% (V1, V2) respectively, increased after 60 days to 12.40 ± 0.41 (V1), 9.74 ± 0.28 (V2) for C/N, 21.94 ± 0.63 mg∙kg−1 (V1) and 22.04 ± 0.04 mg∙kg−1 (V2) for P, 0.96% ± 0.0% (V1) and 1.22 ± 0.04 (V2) for TN. The application of 6 t∙ha−1of PM had the greatest influence on the diameter and weight of the flower heads (27.16 ± 4.01 t∙ha−1 and 230.83 ± 2.64 t∙ha−1), while 4 t∙ha−1 of V2 gave the tallest sunflower plants (110.07 ± 73.28 cm) as well as the diameter at the crown (19.30 ± 9.07 cm). However, CEC was most influenced by 4 t∙ha−1 of V1, while 4 t∙ha−1 of PM had the greatest effect on organic carbon and phosphorus. However, 5 t∙ha−1 of PM showed the highest sunflower production and yield (1.67 ± 0.21 t∙ha−1). The combination with 900 earthworms is recommended for composting and 5 t∙ha−1 of PM is recommended to obtain a better sunflower production.

Soil Fertility Properties of Tobacco Growing Area in Jiyuan

Soil fertility properties of the main tobacco growing area in Jiyuan （Shaoyuan,Wangwu,Xiaye and Daiyu） in west Henan Province were analyzed. Results showed that Jiyuan was one of the potential areas which could produce tobacco leaves with high quality. Its main properties of soli fertility were as follows：the content of total nitrogen,alkali-hydrolysable nitrogen,olsen-phosphorus and organic matters were suitable for high-quality tobacco production; especially,all the flue-cured tobacco growing areas in Henan Province were rich in available potassium; besides,the concentrate of water soluble chloride ion was at reasonable level. The problem was that the micro-elements such as Zn-DTPA and available boron content were at a low level in individual areas. Based on this survey,the recommendations for fertilization in Jiyuan such as stabilizing nitrogen rate,increasing phosphorus,stabilizing potassium,and applying boron commonly and supplementing zinc for the deficient soils were put forward.

Effects of Different Nutrient Management Systems and Cultivation Methods on Crop Yield and Soil Fertility

[Objective] The aim was to provide scientific basis for improving the middle and low yielding fields fertility and farmland productivity. [Method] A field experiment was carried out to study the effects of different management practices （including nutrient management systems and cultivation methods） on crop yield and soil fertility in winter wheat/summer maize rotation system. [Result] The crop yield in the treatment of the high yield and high efficiency system was remarkably higher than farmer conventional management practice. After five crop seasons experiment, the contents of soil organic matter for high yield and high efficiency system increased 2.72-3.01 g/kg, and that of soil total nitrogen increased 0.12-0.16 g/kg, the soil Olsen-P increased 5.2 mg/kg and the soil available K （NH4OAC-K） increased about 37.8 mg/kg. [Conclusion] Considering the yield and soil fertility comprehensively, the management system of high yield and high efficiency could effectively increase the crop yield and improve the soil fertility.

Effects of Straw Returning to Fields on Soils and Current Status in Anhui Province

In the research, effects of straw returning to fields on soil temperature, water, volume-weight, porosity, trace elements, and organic matters were reviewed and countermeasures were proposed to promote straw returning on basis of straw resources and present status in Anhui Province.

Effects of the Application of Controlled Release Nitrogen Fertilizer on Rapeseed Yield, Agronomic Characters and Soil Fertility

In order to study the effects of controlled release nitrogen fertilizer （CRNF） application on rapeseed, a simulated experiment was carried out with 3 types of paddy soils in Dongting Lake area for 4 consecutive years of applying CRNF under double rice cropping system after planting rapeseed crop in the fallow season. The effects of CRNF application on rapeseed yield, agronomic characters and soil fertility were studied in this paper. The results showed that CRNF application improved the growth of rapeseed plant and increased rapeseed yield of CRNF treatments in the purple calcareous clayed paddy soil （PCS） and alluvial loamy paddy soil （ALS） which respectively increased by 12.2% and 9.8% compared with applying urea, re- spectively. The rapeseed yield in 70% CRNF treatment obviously decreased com- pared with urea treatment. The contents of available N and organic carbon in soil increased by 25.0% and 3.2% in CRNF treatment in the ALS after rapeseed crop, respectively; and available N increased by 13.5% in the PCS. Both rapeseed yield and soil fertility in CRNF treatment and 70% CRNF treatment were lower than those in CK treatment in the reddish yellow clayed paddy soil （RYS）. The results al- so indicated that the functions of CRNF application on rapeseed yield increase and soil nitrogen fertility improvement were very obvious in the PCS and ALS.

Soil Quality Evaluation and Technology Research on Improving Land Capability——A Case Study on Huanghuaihai Plain in Shandong Province

Based on the geochemical data obtained from the national project about the prevention and control of soil contamination, this paper explored the properties of soil chemical elements in Huanghuaihai Plain, Shandong Province. The results showed that among the grade-one nutritive elements in soil, organic matter, nitrogen and phosphorus were relatively deficient while potassium was rich. Meanwhile, as the grade-two nutritive elements, calcium oxide and magnesium oxide were relatively short and sulfur’s content was abundant. About the other beneficial and trace nutri-tive elements, iron oxide, manganese, molybdenum and boron were deficient, but the content of chlorine was high, hardly lack. The main barriers to improving land productivity were soil salinization and soil heavy metal contamination. The values of soil integrated fertility index that most of the soil in the study area is middle-lower fertilized. Specifical y, the low fertility area and lower fertility area are 6 1604 and 1 244 km2 respectively, occupying about 97.43% and 1.97% of the total area. The moderate fertility soil has an area of 172 km2, occupying about 0.27% of the total area. The higher fertility soil covers an area of 128 km2, while the high fertility area of only 76 km2. This article proposed scientific fertilization, elimination of soil obsta-cle, remediation of heavy-metal-contaminated soil and other effective measures to improve land productivity according to the basic investigation results, which provides a good technological support for the planning and development of good-quality and high-benefit agriculture.

Responses of Crop Yields and Soil Fertility to Long-term Nutrient Lacking

[Objective] Long-term （over 18 years） fertilization experiments were con- ducted to study the responses of crop yields and soil fertility to long-term nutrient lacking at Zhengzhou in China. [Method] The present study consisted of five treat- ments： 1 CK （no fertilizer or manure）, （2） NP （nitrogen and phosphorus fertilizer applied）, 31 NK （nitrogen and potassium fertilizer applied）, 4 PK （phosphorus and potassium fertilizer applied） and ：5 NPK （nitrogen, phosphorus and potassium fertil- izer applied）. [Result] Lacking of nitrogen or phosphorus led to a low yield; however, there was no significant difference in grain yields between the NP and NPK treat- ments which maintained a higher yield. Receiving no phosphorus, soil available phosphorus content declined to about 2.5 mg/kg. The concentration of soil ex- changeable potassium remained constant at a level of 60 mg/kg under the treat- ments without potassium fertilizer addition. Soil potassium spontaneous supply ca- pacity fluctuated around 100%.[Conclusion] In fluvo-aquic soil, nitrogen and phos- phorus were two key limiting factors to grain yields, biomass and yield component factors of wheat and maize, while potassium was not. However, potassium defi- ciency may occur in the future if there was still no potassium fertilizer applied.

Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System

[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer （CK）, urea, controlled release nitrogen fertilizer （CRNF） and 70% controlled release nitrogen fertilizer （70% CRNF） were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil （ALS）, purple calcareous clayey paddy soil （PCS）, and reddish yellow loamy paddy soil （RYS）, respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system.

Effects of Dairy Cattle Manure and Chemical Fertilizers on Fertility of Soils Grown with Cichorium intybus

[Objective] The aim was to explore recycling utilization of manure of dairy cattle through returning of manures into fields. [Method] Effects of dairy cattle ma- nure and chemical fertilizer on fertility of soils grown with Cichorium intybus were in- vestigated through a pot experiment. [Result] After manure of dairy cattle was ap- plied, it can be concluded that organic matter, total N, total P, alkali-hydrolyzable ni- trogen, available P, activities of urease and invertase in soils increased by 0.14-1.28 times, 43.8%-79.7%, 17.4%-30.8%, 147%-188%, 7 times, 17.2%-38.5%, and 1.36%- 3.34%, respectively. Furthermore, organic matter, total N. urease and invertase activi- ties in group of M7F3 increased most; total P and available P achieved the best in group of M3F7. These indicated that the applied manures of dairy cattle would maintain and improve soil fertility, providing better soils for Cichorium intybus. [Conclusion] The research provides reference for recycling of cattle manures and construction of ecological cyclical pattern of ＂grass planting-cattle breeding-methane fermentation-returning of manures into fields＂.

Correlation between Yield of Coptis chinensis Franch. and Soil Nutrients under Different Forests

[Objective] This study was conducted to investigate the correlation be- tween yield of Coptis chinensis Franch. and soil nutrients under different forests. [Method] The soil nutrients and yields of C. chinensis in fallow field, Cryptomeria japonica forest, Magnolia officinalis forest and Phellodendron chinense forest planted with C. chinensis were investigated. [Result] The contents of soil nitrogen （total ni- trogen, alkali-hydrolyzale nitrogen）, organic matter, potassium and phosphorous under the planting mode of C. chinensis under C. japonica forest were the highest; and the contents of organic matter and total nitrogen in the soils of M. officinalis and P. chinense forests were close to each other at the medium abundant level, and the phosphorous contents were more abundant than those in fallow field. [Conclusion] This study could provide a theoretical basis for scientific fertilization.

Overall Evaluation of Organic Paddy Soil Fertility

[Objective] The aim was to explore soil quality and fertility of organic rice fields in Daizhuang Village. [Method] The analysis was made based on soil samples from different areas where planting methods varied after harvest of organic rice. [Result] The content of organic matter improved generally in fields of organic rice in Daizhuang. Specifically, the contents of N, P and K were not high, and the contents of N and P declined in the fields with crop rotation of organic rice Astragalus sin# cus, but the content of K increased. [Conclusion] It is of great significance for soil fertility to develop and promote crop rotation of organic rice Astragalus sinicus, which also advances quality of organic rice.

Effects of N,P and K Fertilizers on Growth of Clover Nitrogen-fixing Rhizobia and Soil Fertility after Plantation

In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation were investigated, thereby providing certain reference for reasonable cultivation of clover and improvement of soil fertility. A two-year experiment was conducted from 2012 to 2013. The clover was cultivated after rice every year, and different levels of N, P and K fertilizers were applied before winter. In the treatment group, no fertilizer was applied. The effects of different fertilizers and different application amounts on clover yield, nitrogen-fixing rhizobia quantity, nitrogen-fixing rhizobia weight and soil fertility after plantation were analyzed. The results showed that the application of N, P and K fertilizers in the early stage had significantly effect on the growth of clover. When the application amount of N fertilizer was 75 kg/hm^2（N 46%）, the clover yield, nitrogen-fixing rhizobia quantity and nitrogen-fixing rhizobia weight were highest. The soil nitrogen content after plantation increased with the increase of the application amount of N fertilizer, while the P and K content decreased and then increased with the increased application amounts. Soil available P content increased with the increased application amounts of N and P fertilizers, but it did not change significantly with the increased application amount of K fertilizer. Soil available K content increased first and then decreased with the increased application amounts of N and P fertilizers.When the application amounts of N and P fertilizers were 150（N 46%） and 300（P_2O_5 12%） kg/hm^2, soil available K content reached the maximum. Soil organic matter content increased with the increased application amounts of N, P and K fertilizers. Therefore, in the cultivation of clover, appropriate application of N, P and K fertilizers in the early stage can improve clover yield and soil fertility.

Effects of Fertilization Patterns on Chemical Forms of Nitrogen in Dark Brown Soil and Its Distribution in Different Aggregates

[Objective] This study was conducted to investigate the effects of tradition-al fertilization and formula fertilization by soil testing on the chemical forms of nitro-gen in dark brown soil and its distribution in different aggregates. [Method] A physi-co-chemistry method was adopted in a comparative study on the chemical forms of nitrogen and their distribution in different-sized aggregates of dark brown soil under traditional fertilization and formula fertilization by soil testing respectively. [Result] Compared with traditional fertilization in spring and autumn, the formula fertilization by soil testing averagely decreased, the total nitrogen in soil by 23.2% in spring and by 20% in autumn in the soil layer of 0-20 cm, by 48.8% in the layer of 20-40 cm. Ammonium nitrogen was so sensitive to the methods of fertilization that the content of ammonium nitrogen was reduced much more under formula fertitization by soil testing in autumn than under traditional fertilization. Nitrogen in soil under traditional fertilization pattern was mainly distributed in the aggregates of 0-0.25 and 0.5-1 mm, while in formula fertilization by soil testing it was mainly distributed in the aggregates of 0.25-0.5 and 0-0.25 mm. [Conclusion] The study proved that for-mula fertilization by soil testing helped to reduce the risk of nitrogen pol ution and had huge effects on the chemical forms and distribution of nitrogen in different ag-gregates in dark brown soil.

Effects of Soil Fertility on Peanut Quality

[Objective] The research aimed to discuss the key soil fertility factors affecting the peanut quality and quantify the effect degree of the key climatic factors,which will provide scientific basis for peanut quality classification,fine varieties breeding and high-yield cultivation.[Method] Based on the peanut quality data and soil data coming from the 18 main peanut producing provinces in China in 2008,the effects of soil fertility factors on peanut quality was studied by the methods of correlation analysis,path analysis and stepwise regression analysis.[Result] The results showed that the total nitrogen content in soil was the main factors affecting the peanut protein content,and the relationship between them was Y=0.000 179 4X2＋25.597.The organic matter content in soil was the main factors affecting the peanut fat content,and the relationship between them was Y=0.162X1＋43.317.The organic matter content in soil was also the main factors affecting the O/L of peanut,and the relationship between them was Y=0.162X1＋43.317.[Conclusion] Different fertility factors had the different effects on the peanut quality,so an appropriate ratio of the fertilizers should be adopted to improve the peanut quality.

Effect of Fertilization on Soil Fertility and Wheat Yield of Dryland in the Loess Plateau

Long-term fertility experiments have become an important tool for investigating the sustainability of cropping systems. Therefore, a long-term (18-year) fertilization experiment was conducted in Changwu County, Shaanxi Province, China, to ascertain the effect of the long-term application of chemical fertilizers and manure on wheat yield and soil fertility in the Loess Plateau, so as to provide a scientific basis for sustainable land management. The experiment consisted of nine fertilizer treatments with thr…