The integrated development of Tibet "one river and two streams" agricultural ecological basin should control the generated environmental problems and prevent new environmental problems,thereby promoting coor...The integrated development of Tibet "one river and two streams" agricultural ecological basin should control the generated environmental problems and prevent new environmental problems,thereby promoting coordinated development of agricultural economy in the region. It is very necessary and urgent to explore main environmental problems of Tibet " one river and two streams" agricultural ecological basin and effective countermeasures. When developing resources and economy,the principle of combining prevention with control,dominated by prevention and integrated control should be followed; regional advantages,characteristics and environmental self restoring ability should be sufficiently played and used; the policy of integrated prevention and utilization should be used; compensation method,prevention control measures and planning assumption for main environmental problems should be proposed,which could prevent that systemic development of Tibet " one river and two streams" agricultural ecological basin takes the old path of " firstly destroying and then controlling".展开更多
Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-re...Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-response traits and five low-N-tolerance traits were investigated using two inbred line populations(ILs) consisting of recombinant inbred lines(RIL) and advanced backcross(ABL) populations,derived from crossing Ye478 with Wu312.Both populations were crossed with P178 to construct two testcross populations.IL populations,their testcross populations,and the midparent heterosis(MPH)for NUE were investigated.Kernel weight,kernel number,and kernel number per row were sensitive to N level and ILs showed higher N response than did the testcross populations.Based on a highdensity linkage map,138 quantitative trait loci(QTL) were mapped,each explaining 5.6%–38.8% of genetic variation.There were 52,34 and 52 QTL for IL populations,MPH,and testcross populations,respectively.The finding that 7.6% of QTL were common to the ILs and their testcross populations and that 11.7% were common to the MPH and testcross population indicated that heterosis for NUE traits was regulated by non-additive and non-dominant loci.A QTL on chromosome 5 explained 27% of genetic variation in all of the traits and Gln1-3 was identified as a candidate gene for this QTL.Genome-wide prediction of NUE traits in the testcross populations showed 14%–51% accuracy.Our results may be useful for clarifying the genetic basis of heterosis for NUE traits and the candidate gene may be used for genetic improvement of maize NUE.展开更多
The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evid...The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge gap.The experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block design.The results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))respectively.Reduced fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving irrigation.Hence,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water pollution.Further studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching losses.The benefits at different climatic conditions,soil types,and fertilizer types with application methods are also a research gap.展开更多
The rapidly growing world population,water shortage,and food security are promising problems for sustainable agriculture.Farmers adopt higher irrigation and fertilizer applications to increase crop production resultin...The rapidly growing world population,water shortage,and food security are promising problems for sustainable agriculture.Farmers adopt higher irrigation and fertilizer applications to increase crop production resulting in environmental pollution.This study aimed to identify the long-term effects of intelligent water and fertilizers used in corn yield and soil nutrient status.A series of field experiments were conducted for six years with treatments as:farmer accustomed to fertilization used as control(CON),fertilizer decrement(KF),fertilizer decrement+watersaving irrigation(BMP1);combined application of organic and inorganic fertilizer+water-saving irrigation(BMP2),and combined application of controlled-release fertilizer(BMP3).A significant improvement was observed in soil organic matter(14.9%),nitrate nitrogen(106.7%),total phosphorus(23.9%),available phosphorus(26.2%),straw yield(44.8%),and grain yield(54.7%)with BMP2 treatment as compared to CON.The study concludes that integrating chemical and organic fertilizers with water-saving irrigation(BMP2)is a good approach to increasing corn productivity,ensuring water safety and improving soil health.The limitations of the current study include the identification of fertilizer type and its optimum dose,irrigation water type,and geographical position.展开更多
Continuous cropping(CC)obstacle is a major threat in legume crops production;however,the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood.The current 2-year study wa...Continuous cropping(CC)obstacle is a major threat in legume crops production;however,the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood.The current 2-year study was conducted to investigate the effects of different kinds and concentrations of allelochemicals,p-hydroxybenzoic acid(H),cinnamic acid(C),phthalic acid(P),and their mixtures(M)on peanut root growth and productivity in response to CC obstacle.Treatment with H,C,P,and M significantly decreased the plant height,dry weight of the leaves and stems,number of branches,and length of the lateral stem compared with control.Exogenous application of H,C,P,and M inhibited the peanut root growth as indicated by the decreased root morphological characters.The allelochemicals also induced the cell membrane oxidation even though the antioxidant enzymes activities were significantly increased in peanut roots.Meanwhile,treatment with H,C,P,and M reduced the contents of total soluble sugar and total soluble protein.Analysis of ATPase activity,nitrate reductase activity,and root system activity revealed that the inhibition effects of allelochemicals on peanut roots might be due to the decrease in activities of ATPase and NR,and the inhibition of root system.Consequently,allelochemicals significantly decreased the pod yield of peanut compared with control.Our results demonstrate that allelochemicals play a dominant role in CC obstacle-induced peanut growth inhibition and yield reduction through damaging the root antioxidant system,unbalancing the osmolytes accumulation,and decreasing the activities of root-related enzymes.展开更多
Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source poll...Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source pollution and the current situation of agricultural non-point source pollution prevention and control in China. In view of the serious agricultural non-point source pollution in water environment of Guangxi and the difference in quality of drinking water between urban and rural areas,it came up with recommendations for strengthening agricultural non-point source pollution prevention and control from scientific distribution,linked operation and maintenance,popular science education,and legal system construction,to guarantee safe and healthy drinking water in rural areas.展开更多
As a basic industry in Tibet Autonomous Region,the development of agriculture and animal husbandry circular economy is of great practical significance,which is actively reflected in national high-quality development a...As a basic industry in Tibet Autonomous Region,the development of agriculture and animal husbandry circular economy is of great practical significance,which is actively reflected in national high-quality development and new agriculture and animal husbandry circular model.The development direction and future trend directly determine the promotion and enhancement of regional agriculture and animal husbandry economy,which is highly valued and welcomed by academic circles.This paper mainly expounds the development connotation of agriculture and animal husbandry circular economy system from the perspective of Tibet's agriculture and animal husbandry economic development.It focuses on sorting out the construction and future direction of circular economy development system,effectively puts forward ideas and comprehensive understanding of the circular economy development system of agriculture and animal husbandry in Tibet,effectively promotes the promotion and basic change of circular economy of agriculture and animal husbandry,and effectively changes the traditional development model and new innovation model of agriculture and animal husbandry.展开更多
On the basis of introducing the nutrient composition and biogas fertilizer,the effects of biogas fertilizer on soil,crops and environment are summarized. Biogas fertilizer can improve soil structure,increase soil orga...On the basis of introducing the nutrient composition and biogas fertilizer,the effects of biogas fertilizer on soil,crops and environment are summarized. Biogas fertilizer can improve soil structure,increase soil organic matter,available nutrient contents and enzyme activity,increase crop yield,quality and resistance,and relieve the non-point source pollution effectively. The harmlessness,application technology and risk are analyzed. Some suggestions are put forward to control the source pollution,strengthen the research of fermentation technology,define the standard of biogas fertilizer,and carry out large and medium-sized biogas engineering.展开更多
Excessive fertilization has led to nutrient use inefficiency and serious environmental consequences for radish cultivation in North China.The Nutrient Expert(NE)system is a science-based,site-specific fertilization de...Excessive fertilization has led to nutrient use inefficiency and serious environmental consequences for radish cultivation in North China.The Nutrient Expert(NE)system is a science-based,site-specific fertilization decision support system,but the updated NE system for radish has rarely been evaluated.This study aims to validate the feasibility of NE for radish fertilization management from agronomic,economic,and environmental perspectives.A total of 46 field experiments were conducted over four seasons from April 2018 to November 2019 across the major radish growing regions in North China.The results indicated that NE significantly reduced N,P_(2)O_(5),and K_(2)O application rates by 98,110,and 47 kg ha^(-1) relative to those in the farmers’practice(FP),respectively,and reduced N and P_(2)O_(5) inputs by 48 and 44 kg ha^(-1),respectively,while maintaining the same K_(2)O rate as soil testing(ST).Relative to FP and ST,NE significantly increased radish yield by 2.7 and 2.6 t ha^(-1)(4.2 and 4.0%)and net returns by 837 and 432 USD ha^(-1),respectively.On average,NE significantly improved the agronomic efficiency(AE)of N,P,and K(relative to FP and ST)by 42.4 and 31.0,67.4 kg kg^(-1) and 50.9,and 20.3 and 12.3 kg kg^(-1);enhanced the recovery efficiency(RE)of N,P,and K by 11.4 and 7.0,14.1 and 7.5,and 11.3 and 6.3 percentage points;and increased the partial factor productivity(PFP)of N,P,and K by 162.9 and 96.8,488.0 and 327.3,and 86.9 and 22.4 kg kg^(-1),respectively.Furthermore,NE substantially reduced N and P_(2)O_(5) surpluses by 105.1 and 115.1 kg ha^(-1),respectively,and decreased apparent N loss by 110.8 kg ha^(-1) compared to FP.These results indicated that the NE system is an effective and feasible approach for improving NUE and promoting cleaner radish production in North China.展开更多
Agricultural economic development of Tibet Autonomous Region mainly concentrates in the "One River and Two Streams" agricultural production basin. The basin is main concentrated place for agricultural resour...Agricultural economic development of Tibet Autonomous Region mainly concentrates in the "One River and Two Streams" agricultural production basin. The basin is main concentrated place for agricultural resources development,economic construction and population aggregation,and the region playing the advantages of Tibetan agriculture,corresponding with the practice,and enhancing self development and innovation. In the multi-year development and construction,it develops regional large agriculture,builds irrigation and water conservancy facilities,vigorously changes medium and low-yield land,actively develops animal husbandry and agriculture,and gradually promotes the effective combination of traffic industry and transportation industry,which has made considerable achievements. But in the face of today's increasingly advocated theme of "building beautiful Tibet and constructing ecological home",the construction of environmental problems lacking the systemic research is the prominent and fundamental problem in the "One River and Two Streams" agricultural production basin. Meanwhile,environment construction is an important part of economic development planning,and the solving of environmental protection problem is the historical mission in the contemporary and future generations. Therefore,it is very necessary to study the environment problems in Tibet "One River and Two Streams" agricultural production basin. The "One River and Two Streams" agricultural production basin is preliminarily explored for providing reference for the relevant environmental departments.展开更多
Tibet is not only famous " the roof of the world" but also is recognized as the " third pole of the earth" by the whole world,with very important significance in construction and protection of plat...Tibet is not only famous " the roof of the world" but also is recognized as the " third pole of the earth" by the whole world,with very important significance in construction and protection of plateau eco-environment. In Qinghai-Tibet Plateau,there are abundant wild animal and plant resources and a lot of high-mountain mineral resources,and water resources,light resources and characteristic agriculture and animal husbandry resources have broad development and utilization space. When Tibet economy and society improve and develop,eco-environment construction and protection work is also mentioned in the schedule. In this paper,the history,status quo and prospect of Tibet eco-environment protection and development are explored,which could promote the understanding on Tibet eco-environment construction and protection in academic world.展开更多
The status of research on the utilization of vermicompost at home and abroad was reviewed from the aspects of effects of vermicompost on soil in terms of physical,chemical and biological properties,as well as effects ...The status of research on the utilization of vermicompost at home and abroad was reviewed from the aspects of effects of vermicompost on soil in terms of physical,chemical and biological properties,as well as effects of vermicompost as cultivation substrate and organic fertilizer on crop yield and quality improvement.Moreover,some new thoughts and prospects on the application of vermicompost in the development of agricultural and rural ecological recycling industry were put forward.展开更多
The level of agricultural product sales is one of the important factors that directly affect the economic income of rural villagers.Due to the limitations of geographical conditions and the lagging economic and social...The level of agricultural product sales is one of the important factors that directly affect the economic income of rural villagers.Due to the limitations of geographical conditions and the lagging economic and social development,there are major problems in the sales of agricultural products in Shishan area.To better help the sales of agricultural products in Shishan area of northwest Guangxi,Nandan County of Hechi City is taken as research object.Current situation of agricultural products production and sales channels in Nandan County is understood,and problems existing in the sales of agricultural products in Nandan County are analyzed.Moreover,targeted opinions and suggestions are put forward from the aspect of innovating the sales channels of agricultural and sideline products,thereby helping quality improvement and development of agricultural industry.展开更多
With the high-quality development of modern agriculture and animal husbandry in the plateau,the waste resources produced by agriculture and animal husbandry show a trend of diversification.How to effectively carry out...With the high-quality development of modern agriculture and animal husbandry in the plateau,the waste resources produced by agriculture and animal husbandry show a trend of diversification.How to effectively carry out the key work based on the optimal combination and utilization of waste resources of agriculture and animal husbandry in Tibet is imminent.To realize efficient recycling of waste resources of agriculture and animal husbandry,innovative mode is explored.On the theoretical basis,it can effectively alleviate the resource crisis,control the pollution sources,effectively utilize the resources and construct the recycling mode,which plays an important role in promoting,integrating and coordinating the high-quality development of modern agriculture and animal husbandry in the plateau.In this paper,optimal combination and utilization manner of waste resources of agriculture and animal husbandry under the circular development concept is comprehensively analyzed and summarized,to continuously improve reasonable and effective utilization level and efficiency of agricultural waste resources.It could not only inhibit waste pollution but also promote rational and effective utilization of resources,thereby laying theoretical basis for sustainable and efficient development of agriculture and animal husbandry in Tibet,promoting the improvement of agricultural and rural ecological environment,and providing the thinking for exploring model of ecological recycling in plateau.展开更多
A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen(N), phosphorus(P), and potassium(K) uptake, and grain yield of spring maize. The results indicated ...A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen(N), phosphorus(P), and potassium(K) uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development,increased nutrient accumulation, and increased yield. Compared with conventional soil management(CK), root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm(T1) and subsoil tillage to 50 cm(T2) were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.展开更多
Greenhouse vegetable production has been characterized by high agricultural inputs, high temperatures, and high cropping indexes. As an intensive form of agriculture, nutrient cycling induced by microbial activities i...Greenhouse vegetable production has been characterized by high agricultural inputs, high temperatures, and high cropping indexes. As an intensive form of agriculture, nutrient cycling induced by microbial activities in the greenhouses is relatively different from open fields in the same region. However, the responses of soil microbial biomass carbon(MBC) and nitrogen(MBN), enzyme activities, microbial community composition, and yield to organic amendment are not well understood. Therefore, a 5-year greenhouse tomato(Solanum lycopersicum Mill.)-cucumber(Cucumis sativus L.) rotation experiment was conducted. The field experiment comprised 5 treatments: 4/4 CN(CN, nitrogen in chemical fertilizer), 3/4 CN+1/4 MN(MN, nitrogen in pig manure), 2/4 CN+2/4 MN, 2/4 CN+1/4 MN+1/4 SN(SN, nitrogen in corn straw) and 2/4 CN+2/4 SN. The amounts of nitrogen(N), phosphorus(P_2O_5), and potassium(K_2O) were equal in the five treatments. Starting with the fourth growing season, the optimal yield was obtained from soil treated with straw. MBC, MBN, phospholipid fatty acid(PLFA) profiles, and enzyme activities were significantly changed by 5 years of substitution with organic amendments. Redundancy analysis showed that MBC accounts for 89.5 and 52.3% of the total enzyme activity and total community variability, respectively. The activities of phosphomonoesterase, N-acetyl-glucosaminidase, and urease, and the relative abundances of fungi, actinomycetes, and Gram-negative bacteria were significantly and positively related to vegetable yields. Considering the effects of organic amendments on soil microbial characteristics and vegetable yield, 2/4 CN+1/4 MN+1/4 SN can improve soil quality and maintain sustainable high yield in greenhouse vegetable production.展开更多
To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year fi...To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year field experiment,Xianyu 335,a widely released hybrid in China,was planted at 60 000 plants ha^(–1 )(conventional planting density,CD) and 90 000 plants ha^(–1) (high planting density,HD),respectively.Until all the filaments protruded from the ear,at which point the plants were subjected to the removal of 1/2 (T1),1/3 (T2) and 1/4 (T3) each leaf length per plant,no leaf removal served as the control(CK).We evaluated the leaf source reduction on canopy photosynthetic matter production and N accumulation of different planting densities.Under CD,decreasing leaf source markedly decreased photosynthetic rate (P_(n)),effective quantum yield of photosystem II (ΦPSII) and the maximal efficiency of photosystem II photochemistry (F_(v)/F_(m)) at grain filling stage,reduced post-silking dry matter accumulation,harvest index (HI),and the yield.Compared with the CK,the 2-year average yields of T1,T2 and T3 treatments decreased by 35.4,23.8 and 8.3%,respectively.Meanwhile,decreasing leaf source reduced the root bleeding sap intensity,the content of soluble sugar in the bleeding sap,post-silking N uptake,and N accumulation in grain.The grain N accumulation in T1,T2 and T3 decreased by 26.7,16.5 and 12.8% compared with CK,respectively.Under HD,compared to other treatments,excising T3 markedly improved the leaf P_(n),ΦPSII and F_(v)/F_(m) at late-grain filling stage,increased the post-silking dry matter accumulation,HI and the grain yield.The yield of T3 was 9.2,35.7 and 20.1% higher than that of CK,T1 and T2 on average,respectively.The T3 treatment also increased the root bleeding sap intensity,the content of soluble sugar in the bleeding sap and post-silking N uptake and N accumulation in grain.Compared with CK,T1 and T2 treatments,the grain N accumulation in T3 increased by 13.1,40.9 and 25.2% on average,respectively.In addition,under the same source reduction treatment,the maize yield of HD was significantly higher than that of CD.Therefore,planting density should be increased in maize production for higher grain yield.Under HD,moderate decreasing leaf source improved photosynthetic performance and increased the post-silking dry matter accumulation and HI,and thus the grain yield.In addition,the improvement of photosynthetic performance improved the root function and promoted postsilking N uptake,which led to the increase of N accumulation in grain.展开更多
Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated th...Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices.展开更多
Soil aggregation,microbial community,and functions(i.e.,extracellular enzyme activities;EEAs)are critical factors affecting soil C dynamics and nutrient cycling.We assessed soil aggregate distribution,stability,nutrie...Soil aggregation,microbial community,and functions(i.e.,extracellular enzyme activities;EEAs)are critical factors affecting soil C dynamics and nutrient cycling.We assessed soil aggregate distribution,stability,nutrients,and microbial characteristics within>2,0.25-2,0.053-0.25,and<0.053 mm aggregates,based on an eight-year field experiment in a greenhouse vegetable field in China.The field experiment includes four treatments:100%N fertilizer(CF),50%substitution of N frtilizer with manure(M),straw(S),and manure plus straw(MS).The amounts of nutrient(N,P20,and K20)input were equal in each treatment.Results showed higher values of mean weight diameter in organic amended soils(M,MS,and S,2.43-2.97)vs.CF-amended soils(1.99).Relative to CF treatment,organic amendments had positive effects on nutrient(i.e.,available N,P,and soil organic C(SOC))conditions,microbial(e.g,bacterial and fungal)growth,and EEAs in the>0.053 mm aggregates,but not in the<0.053 mm aggregates.The 0.25-0.053 mm aggregates exhibited better nutrient conditions and hydrolytic activity,while the<0.053 mm aggregates had poor nutrient conditions and higher oxidative activity among aggregates,per SOC,available N,available P,and a series of enzyme activities.These results indicated that the 0.25-0.053 mm(<0.053 mm)aggregates provide suitable microhabitats for hydrolytic(oxidative)activity.Interestingly,we found that hydrolytic and oxidative activities were mainly impacted by fertilization(58.5%,P<0.01)and aggregate fractions(50.5%,P<0.01),respectively.The hydrolytic and oxidative activities were significantly(P<0.01)associated with nutrients(SOC and available N)and pH,electrical conductivity,respectively.Furthermore,SOC,available N,and available P closely(P<0.05)afected microbial communities within>0.25,0.25-0.053,and<0.053 mm aggregates,respectively.These findings provide several insights into microbial characteristics within aggregates under dfferent frilization modes in the greenhouse vegetable production system in China.展开更多
With the rapid development of mining,the soil heavy metal contamination is increasingly serious in Shaoguan,directly affecting the production of crops. This paper analyzes the farmland soil heavy metal contamination i...With the rapid development of mining,the soil heavy metal contamination is increasingly serious in Shaoguan,directly affecting the production of crops. This paper analyzes the farmland soil heavy metal contamination in the mining area of Shaoguan and the causes of heavy metal contamination in recent years,brings forward the bioremediation measures to control soil heavy metal contamination,and points out the development direction of bioremediation in farmland soil heavy metal contamination in the mining area.展开更多
基金Supported by “Location Observation Study of Soil Nutrient of Cultivated Land in Tibet Main Climate Type Region” from the Project of Finance Department of Tibet Autonomous Region
文摘The integrated development of Tibet "one river and two streams" agricultural ecological basin should control the generated environmental problems and prevent new environmental problems,thereby promoting coordinated development of agricultural economy in the region. It is very necessary and urgent to explore main environmental problems of Tibet " one river and two streams" agricultural ecological basin and effective countermeasures. When developing resources and economy,the principle of combining prevention with control,dominated by prevention and integrated control should be followed; regional advantages,characteristics and environmental self restoring ability should be sufficiently played and used; the policy of integrated prevention and utilization should be used; compensation method,prevention control measures and planning assumption for main environmental problems should be proposed,which could prevent that systemic development of Tibet " one river and two streams" agricultural ecological basin takes the old path of " firstly destroying and then controlling".
基金financially supported by the National Key Research and Development Program of China (2021YFD1200700)the National Natural Science Foundation of China (31972485,31971948)the Hainan Provincial Science and Technology Plan Sanya Yazhou Bay Science and Technology City Joint Project(320LH011)。
文摘Although the use of heterosis in maize breeding has increased crop productivity,the genetic causes underlying heterosis for nitrogen(N) use efficiency(NUE) have been insufficiently investigated.In this study,five N-response traits and five low-N-tolerance traits were investigated using two inbred line populations(ILs) consisting of recombinant inbred lines(RIL) and advanced backcross(ABL) populations,derived from crossing Ye478 with Wu312.Both populations were crossed with P178 to construct two testcross populations.IL populations,their testcross populations,and the midparent heterosis(MPH)for NUE were investigated.Kernel weight,kernel number,and kernel number per row were sensitive to N level and ILs showed higher N response than did the testcross populations.Based on a highdensity linkage map,138 quantitative trait loci(QTL) were mapped,each explaining 5.6%–38.8% of genetic variation.There were 52,34 and 52 QTL for IL populations,MPH,and testcross populations,respectively.The finding that 7.6% of QTL were common to the ILs and their testcross populations and that 11.7% were common to the MPH and testcross population indicated that heterosis for NUE traits was regulated by non-additive and non-dominant loci.A QTL on chromosome 5 explained 27% of genetic variation in all of the traits and Gln1-3 was identified as a candidate gene for this QTL.Genome-wide prediction of NUE traits in the testcross populations showed 14%–51% accuracy.Our results may be useful for clarifying the genetic basis of heterosis for NUE traits and the candidate gene may be used for genetic improvement of maize NUE.
基金This study received funds from the National Natural Science Foundation of China[41361062]National Natural Science Foundation of China Joint Fund for Regional Innovation and Development[U20A20114]+1 种基金Natural Science Foundation of Ningxia Hui Autonomous Region[2022AAC03449]Station of Observation and Experiment National Agricultural Environment in Yinchuan,Ningxia,China[NAES091AE18].
文摘The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge gap.The experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block design.The results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))respectively.Reduced fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving irrigation.Hence,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water pollution.Further studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching losses.The benefits at different climatic conditions,soil types,and fertilizer types with application methods are also a research gap.
基金This study was supported by the National Natural Science Foundation of China[Grant No.U20A20114]the soil N losses in the greenhouse field in the Yellow River Irrigation as affected by the annual changes of groundwater depth[Grant No.41361062].
文摘The rapidly growing world population,water shortage,and food security are promising problems for sustainable agriculture.Farmers adopt higher irrigation and fertilizer applications to increase crop production resulting in environmental pollution.This study aimed to identify the long-term effects of intelligent water and fertilizers used in corn yield and soil nutrient status.A series of field experiments were conducted for six years with treatments as:farmer accustomed to fertilization used as control(CON),fertilizer decrement(KF),fertilizer decrement+watersaving irrigation(BMP1);combined application of organic and inorganic fertilizer+water-saving irrigation(BMP2),and combined application of controlled-release fertilizer(BMP3).A significant improvement was observed in soil organic matter(14.9%),nitrate nitrogen(106.7%),total phosphorus(23.9%),available phosphorus(26.2%),straw yield(44.8%),and grain yield(54.7%)with BMP2 treatment as compared to CON.The study concludes that integrating chemical and organic fertilizers with water-saving irrigation(BMP2)is a good approach to increasing corn productivity,ensuring water safety and improving soil health.The limitations of the current study include the identification of fertilizer type and its optimum dose,irrigation water type,and geographical position.
基金supported by the National Key R&D Program of China(2018YFD1000902)the Natural Science Foundation of Shandong Province(ZR2021QC163).
文摘Continuous cropping(CC)obstacle is a major threat in legume crops production;however,the underlying mechanisms concerning the roles allelochemicals play in CC obstacle are poorly understood.The current 2-year study was conducted to investigate the effects of different kinds and concentrations of allelochemicals,p-hydroxybenzoic acid(H),cinnamic acid(C),phthalic acid(P),and their mixtures(M)on peanut root growth and productivity in response to CC obstacle.Treatment with H,C,P,and M significantly decreased the plant height,dry weight of the leaves and stems,number of branches,and length of the lateral stem compared with control.Exogenous application of H,C,P,and M inhibited the peanut root growth as indicated by the decreased root morphological characters.The allelochemicals also induced the cell membrane oxidation even though the antioxidant enzymes activities were significantly increased in peanut roots.Meanwhile,treatment with H,C,P,and M reduced the contents of total soluble sugar and total soluble protein.Analysis of ATPase activity,nitrate reductase activity,and root system activity revealed that the inhibition effects of allelochemicals on peanut roots might be due to the decrease in activities of ATPase and NR,and the inhibition of root system.Consequently,allelochemicals significantly decreased the pod yield of peanut compared with control.Our results demonstrate that allelochemicals play a dominant role in CC obstacle-induced peanut growth inhibition and yield reduction through damaging the root antioxidant system,unbalancing the osmolytes accumulation,and decreasing the activities of root-related enzymes.
基金Supported by State Key Research and Development Program of Ministry of Science and Technology"Soil Passivation-Physiological Barrier-Enrichment and Removal Technology in Paddy Field with Mild Cadmium Contamination"(2016YED0800705-01)Key Research and Development Program of Guangxi"Research and Demonstration of Remediation Technology in Cadmium and Lead Polluted Paddy Field"(Gui Ke AB16380084)+2 种基金Key Agricultural Science and Technology Project of Guangxi"Integration,Research and Development of Heavy Metal Pollution Prevention Technology for Paddy Field"(201528)Scientific Research and Technological Development Program Project of Nanning City"Research and Demonstration of Integrated Ecological Restoration Technology for Heavy Metal Cadmium Polluted Paddy Field in Nanning"(20162105)Scientific and Technological Service Ability and Party Informationization Construction of Ecological Comprehensive Demonstration Village in Jianning No.1 Team of Xixiangtang District of Nanning(20152054-13)
文摘Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source pollution and the current situation of agricultural non-point source pollution prevention and control in China. In view of the serious agricultural non-point source pollution in water environment of Guangxi and the difference in quality of drinking water between urban and rural areas,it came up with recommendations for strengthening agricultural non-point source pollution prevention and control from scientific distribution,linked operation and maintenance,popular science education,and legal system construction,to guarantee safe and healthy drinking water in rural areas.
基金Supported by Open Fund Project of Key Laboratory for the Development and Utilization of Rural Renewable Energy of Ministry of Agriculture and Rural Areas(2017015).
文摘As a basic industry in Tibet Autonomous Region,the development of agriculture and animal husbandry circular economy is of great practical significance,which is actively reflected in national high-quality development and new agriculture and animal husbandry circular model.The development direction and future trend directly determine the promotion and enhancement of regional agriculture and animal husbandry economy,which is highly valued and welcomed by academic circles.This paper mainly expounds the development connotation of agriculture and animal husbandry circular economy system from the perspective of Tibet's agriculture and animal husbandry economic development.It focuses on sorting out the construction and future direction of circular economy development system,effectively puts forward ideas and comprehensive understanding of the circular economy development system of agriculture and animal husbandry in Tibet,effectively promotes the promotion and basic change of circular economy of agriculture and animal husbandry,and effectively changes the traditional development model and new innovation model of agriculture and animal husbandry.
基金Supported by National Key Research and Development Program of China(2016YFD0200401)Hebei Science and Technology Project(16227005D)
文摘On the basis of introducing the nutrient composition and biogas fertilizer,the effects of biogas fertilizer on soil,crops and environment are summarized. Biogas fertilizer can improve soil structure,increase soil organic matter,available nutrient contents and enzyme activity,increase crop yield,quality and resistance,and relieve the non-point source pollution effectively. The harmlessness,application technology and risk are analyzed. Some suggestions are put forward to control the source pollution,strengthen the research of fermentation technology,define the standard of biogas fertilizer,and carry out large and medium-sized biogas engineering.
基金the financial support from the National Key Research&Development Program of China(2016FYD0200103)the Fundamental Research Funds for Central Non-profit Scientific Institution,China(1610132019047)。
文摘Excessive fertilization has led to nutrient use inefficiency and serious environmental consequences for radish cultivation in North China.The Nutrient Expert(NE)system is a science-based,site-specific fertilization decision support system,but the updated NE system for radish has rarely been evaluated.This study aims to validate the feasibility of NE for radish fertilization management from agronomic,economic,and environmental perspectives.A total of 46 field experiments were conducted over four seasons from April 2018 to November 2019 across the major radish growing regions in North China.The results indicated that NE significantly reduced N,P_(2)O_(5),and K_(2)O application rates by 98,110,and 47 kg ha^(-1) relative to those in the farmers’practice(FP),respectively,and reduced N and P_(2)O_(5) inputs by 48 and 44 kg ha^(-1),respectively,while maintaining the same K_(2)O rate as soil testing(ST).Relative to FP and ST,NE significantly increased radish yield by 2.7 and 2.6 t ha^(-1)(4.2 and 4.0%)and net returns by 837 and 432 USD ha^(-1),respectively.On average,NE significantly improved the agronomic efficiency(AE)of N,P,and K(relative to FP and ST)by 42.4 and 31.0,67.4 kg kg^(-1) and 50.9,and 20.3 and 12.3 kg kg^(-1);enhanced the recovery efficiency(RE)of N,P,and K by 11.4 and 7.0,14.1 and 7.5,and 11.3 and 6.3 percentage points;and increased the partial factor productivity(PFP)of N,P,and K by 162.9 and 96.8,488.0 and 327.3,and 86.9 and 22.4 kg kg^(-1),respectively.Furthermore,NE substantially reduced N and P_(2)O_(5) surpluses by 105.1 and 115.1 kg ha^(-1),respectively,and decreased apparent N loss by 110.8 kg ha^(-1) compared to FP.These results indicated that the NE system is an effective and feasible approach for improving NUE and promoting cleaner radish production in North China.
基金Sponsored by Finance Item of Tibet Autonomous Region
文摘Agricultural economic development of Tibet Autonomous Region mainly concentrates in the "One River and Two Streams" agricultural production basin. The basin is main concentrated place for agricultural resources development,economic construction and population aggregation,and the region playing the advantages of Tibetan agriculture,corresponding with the practice,and enhancing self development and innovation. In the multi-year development and construction,it develops regional large agriculture,builds irrigation and water conservancy facilities,vigorously changes medium and low-yield land,actively develops animal husbandry and agriculture,and gradually promotes the effective combination of traffic industry and transportation industry,which has made considerable achievements. But in the face of today's increasingly advocated theme of "building beautiful Tibet and constructing ecological home",the construction of environmental problems lacking the systemic research is the prominent and fundamental problem in the "One River and Two Streams" agricultural production basin. Meanwhile,environment construction is an important part of economic development planning,and the solving of environmental protection problem is the historical mission in the contemporary and future generations. Therefore,it is very necessary to study the environment problems in Tibet "One River and Two Streams" agricultural production basin. The "One River and Two Streams" agricultural production basin is preliminarily explored for providing reference for the relevant environmental departments.
基金Supported by the Program of Tibet Autonomous Region Finance Department(Long-term Positioning Observation Research of Soil Nutrient in Main Climate Type Zone of Tibet)
文摘Tibet is not only famous " the roof of the world" but also is recognized as the " third pole of the earth" by the whole world,with very important significance in construction and protection of plateau eco-environment. In Qinghai-Tibet Plateau,there are abundant wild animal and plant resources and a lot of high-mountain mineral resources,and water resources,light resources and characteristic agriculture and animal husbandry resources have broad development and utilization space. When Tibet economy and society improve and develop,eco-environment construction and protection work is also mentioned in the schedule. In this paper,the history,status quo and prospect of Tibet eco-environment protection and development are explored,which could promote the understanding on Tibet eco-environment construction and protection in academic world.
基金Supported by Key Research and Development Project of Nanning Scientific Research and Technology Development(20182026)Major Science and Technology Project of Guangxi Province(GK AA17202026)Key Research and Development Program of Guangxi Province(GK AB19245042)。
文摘The status of research on the utilization of vermicompost at home and abroad was reviewed from the aspects of effects of vermicompost on soil in terms of physical,chemical and biological properties,as well as effects of vermicompost as cultivation substrate and organic fertilizer on crop yield and quality improvement.Moreover,some new thoughts and prospects on the application of vermicompost in the development of agricultural and rural ecological recycling industry were put forward.
基金Supported by Guangxi Environmental Sustainable Rural Development Demonstration Project(55261-0012022)Special Action Project of"Strengthening Agriculture and Enriching the People"and"Six Ones"of the Scientific and Technological Pioneer(GUINONGKEMENG202214)。
文摘The level of agricultural product sales is one of the important factors that directly affect the economic income of rural villagers.Due to the limitations of geographical conditions and the lagging economic and social development,there are major problems in the sales of agricultural products in Shishan area.To better help the sales of agricultural products in Shishan area of northwest Guangxi,Nandan County of Hechi City is taken as research object.Current situation of agricultural products production and sales channels in Nandan County is understood,and problems existing in the sales of agricultural products in Nandan County are analyzed.Moreover,targeted opinions and suggestions are put forward from the aspect of innovating the sales channels of agricultural and sideline products,thereby helping quality improvement and development of agricultural industry.
基金Supported by Open Fund Project of Key Laboratory for the Development and Utilization of Rural Renewable Energy of Ministry of Agriculture and Rural Areas(2017015)。
文摘With the high-quality development of modern agriculture and animal husbandry in the plateau,the waste resources produced by agriculture and animal husbandry show a trend of diversification.How to effectively carry out the key work based on the optimal combination and utilization of waste resources of agriculture and animal husbandry in Tibet is imminent.To realize efficient recycling of waste resources of agriculture and animal husbandry,innovative mode is explored.On the theoretical basis,it can effectively alleviate the resource crisis,control the pollution sources,effectively utilize the resources and construct the recycling mode,which plays an important role in promoting,integrating and coordinating the high-quality development of modern agriculture and animal husbandry in the plateau.In this paper,optimal combination and utilization manner of waste resources of agriculture and animal husbandry under the circular development concept is comprehensively analyzed and summarized,to continuously improve reasonable and effective utilization level and efficiency of agricultural waste resources.It could not only inhibit waste pollution but also promote rational and effective utilization of resources,thereby laying theoretical basis for sustainable and efficient development of agriculture and animal husbandry in Tibet,promoting the improvement of agricultural and rural ecological environment,and providing the thinking for exploring model of ecological recycling in plateau.
基金supported by the National Key Technology R&D Program of China(2012BAD04B02,2013BAD07B02,and2011BAD16B10)the Special Fund for Agro-Scientific Research in the Public Interest(201103003 and 201303126-4)the Key Technology R&D Program of Jilin province,China(20126026)
文摘A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen(N), phosphorus(P), and potassium(K) uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development,increased nutrient accumulation, and increased yield. Compared with conventional soil management(CK), root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm(T1) and subsoil tillage to 50 cm(T2) were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.
基金supported by the National Key Research and Development Program of China (2016YFD0201001)the earmarked fund for China Agriculture Research System (CARS-23-B02)the Key Research and Development Program of Shandong Province,China (2017CXGC0206)
文摘Greenhouse vegetable production has been characterized by high agricultural inputs, high temperatures, and high cropping indexes. As an intensive form of agriculture, nutrient cycling induced by microbial activities in the greenhouses is relatively different from open fields in the same region. However, the responses of soil microbial biomass carbon(MBC) and nitrogen(MBN), enzyme activities, microbial community composition, and yield to organic amendment are not well understood. Therefore, a 5-year greenhouse tomato(Solanum lycopersicum Mill.)-cucumber(Cucumis sativus L.) rotation experiment was conducted. The field experiment comprised 5 treatments: 4/4 CN(CN, nitrogen in chemical fertilizer), 3/4 CN+1/4 MN(MN, nitrogen in pig manure), 2/4 CN+2/4 MN, 2/4 CN+1/4 MN+1/4 SN(SN, nitrogen in corn straw) and 2/4 CN+2/4 SN. The amounts of nitrogen(N), phosphorus(P_2O_5), and potassium(K_2O) were equal in the five treatments. Starting with the fourth growing season, the optimal yield was obtained from soil treated with straw. MBC, MBN, phospholipid fatty acid(PLFA) profiles, and enzyme activities were significantly changed by 5 years of substitution with organic amendments. Redundancy analysis showed that MBC accounts for 89.5 and 52.3% of the total enzyme activity and total community variability, respectively. The activities of phosphomonoesterase, N-acetyl-glucosaminidase, and urease, and the relative abundances of fungi, actinomycetes, and Gram-negative bacteria were significantly and positively related to vegetable yields. Considering the effects of organic amendments on soil microbial characteristics and vegetable yield, 2/4 CN+1/4 MN+1/4 SN can improve soil quality and maintain sustainable high yield in greenhouse vegetable production.
基金the National Key Research and Development Program of China(2016YFD0300103,2017YFD0300603)the Innovation Engineering Plan Project of Jilin Province,China(CXGC2017ZY015)。
文摘To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year field experiment,Xianyu 335,a widely released hybrid in China,was planted at 60 000 plants ha^(–1 )(conventional planting density,CD) and 90 000 plants ha^(–1) (high planting density,HD),respectively.Until all the filaments protruded from the ear,at which point the plants were subjected to the removal of 1/2 (T1),1/3 (T2) and 1/4 (T3) each leaf length per plant,no leaf removal served as the control(CK).We evaluated the leaf source reduction on canopy photosynthetic matter production and N accumulation of different planting densities.Under CD,decreasing leaf source markedly decreased photosynthetic rate (P_(n)),effective quantum yield of photosystem II (ΦPSII) and the maximal efficiency of photosystem II photochemistry (F_(v)/F_(m)) at grain filling stage,reduced post-silking dry matter accumulation,harvest index (HI),and the yield.Compared with the CK,the 2-year average yields of T1,T2 and T3 treatments decreased by 35.4,23.8 and 8.3%,respectively.Meanwhile,decreasing leaf source reduced the root bleeding sap intensity,the content of soluble sugar in the bleeding sap,post-silking N uptake,and N accumulation in grain.The grain N accumulation in T1,T2 and T3 decreased by 26.7,16.5 and 12.8% compared with CK,respectively.Under HD,compared to other treatments,excising T3 markedly improved the leaf P_(n),ΦPSII and F_(v)/F_(m) at late-grain filling stage,increased the post-silking dry matter accumulation,HI and the grain yield.The yield of T3 was 9.2,35.7 and 20.1% higher than that of CK,T1 and T2 on average,respectively.The T3 treatment also increased the root bleeding sap intensity,the content of soluble sugar in the bleeding sap and post-silking N uptake and N accumulation in grain.Compared with CK,T1 and T2 treatments,the grain N accumulation in T3 increased by 13.1,40.9 and 25.2% on average,respectively.In addition,under the same source reduction treatment,the maize yield of HD was significantly higher than that of CD.Therefore,planting density should be increased in maize production for higher grain yield.Under HD,moderate decreasing leaf source improved photosynthetic performance and increased the post-silking dry matter accumulation and HI,and thus the grain yield.In addition,the improvement of photosynthetic performance improved the root function and promoted postsilking N uptake,which led to the increase of N accumulation in grain.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-23-B04)the National Key Research and Development Program of China(2016YFD0201001)。
文摘Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices.
基金Fund for China Agriculture Research 3ystem(CAR3-23-B02)the National Key Research and Development Program of China(2016YFD0201001)the Key Research and Development Program of Shandong Province,China(2017CXGC0206).
文摘Soil aggregation,microbial community,and functions(i.e.,extracellular enzyme activities;EEAs)are critical factors affecting soil C dynamics and nutrient cycling.We assessed soil aggregate distribution,stability,nutrients,and microbial characteristics within>2,0.25-2,0.053-0.25,and<0.053 mm aggregates,based on an eight-year field experiment in a greenhouse vegetable field in China.The field experiment includes four treatments:100%N fertilizer(CF),50%substitution of N frtilizer with manure(M),straw(S),and manure plus straw(MS).The amounts of nutrient(N,P20,and K20)input were equal in each treatment.Results showed higher values of mean weight diameter in organic amended soils(M,MS,and S,2.43-2.97)vs.CF-amended soils(1.99).Relative to CF treatment,organic amendments had positive effects on nutrient(i.e.,available N,P,and soil organic C(SOC))conditions,microbial(e.g,bacterial and fungal)growth,and EEAs in the>0.053 mm aggregates,but not in the<0.053 mm aggregates.The 0.25-0.053 mm aggregates exhibited better nutrient conditions and hydrolytic activity,while the<0.053 mm aggregates had poor nutrient conditions and higher oxidative activity among aggregates,per SOC,available N,available P,and a series of enzyme activities.These results indicated that the 0.25-0.053 mm(<0.053 mm)aggregates provide suitable microhabitats for hydrolytic(oxidative)activity.Interestingly,we found that hydrolytic and oxidative activities were mainly impacted by fertilization(58.5%,P<0.01)and aggregate fractions(50.5%,P<0.01),respectively.The hydrolytic and oxidative activities were significantly(P<0.01)associated with nutrients(SOC and available N)and pH,electrical conductivity,respectively.Furthermore,SOC,available N,and available P closely(P<0.05)afected microbial communities within>0.25,0.25-0.053,and<0.053 mm aggregates,respectively.These findings provide several insights into microbial characteristics within aggregates under dfferent frilization modes in the greenhouse vegetable production system in China.
基金Supported by National Natural Science Foundation of China(U1033004-06)Guangxi Key Agricultural Science Planning Project(201528)
文摘With the rapid development of mining,the soil heavy metal contamination is increasingly serious in Shaoguan,directly affecting the production of crops. This paper analyzes the farmland soil heavy metal contamination in the mining area of Shaoguan and the causes of heavy metal contamination in recent years,brings forward the bioremediation measures to control soil heavy metal contamination,and points out the development direction of bioremediation in farmland soil heavy metal contamination in the mining area.
