The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards...The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation.展开更多
[Objective] The research aimed to evaluate the phosphorus balances in the main crop production systems in Shunyi District of Beijing City.[Method] By using the nutrient budget method,the phosphorus balances in the mai...[Objective] The research aimed to evaluate the phosphorus balances in the main crop production systems in Shunyi District of Beijing City.[Method] By using the nutrient budget method,the phosphorus balances in the main crop production systems(field crops,orchard and open-field vegetables) in Shunyi District of Beijing City were evaluated.Moreover,the main influence elements of phosphorus surplus in the farmland were analyzed.[Result] The positive phosphorus balances were found across all three crop production systems in the study period.The amount of phosphorus surplus [491.8 kg/(hm2·a)] in vegetables production system was significantly higher than that in field crops [82.7 kg/(hm2·a)] and orchard [129.5 kg/(hm2·a)] production systems(P0.05).But the amount of phosphorus surplus between the latter two had no significant difference(P0.05).Phosphorus surpluses in the production systems of field crops and vegetables respectively presented the extremely significant and positive relationship with the phosphorus input from chemical fertilizer and organic fertilizer(r was respectively 0.987 7 and 0.970 1).The phosphorus input from chemical fertilizer and organic fertilizer in the orchard production system both presented the extremely significant and positive relationship with the phosphorus surplus in the farmland(r was respectively 0.836 3 and 0.625 2).However,the phosphorus harvested by crops didn't significantly correlated to the phosphorus surplus in the farmland for all three crop production systems(P0.05).[Conclusion] The risk of phosphorus pollution potential in all three crop production system of Shunyi Distirct was high,especially in the vegetable production system.The phosphorus surpluses in the production systems of field crops and vegetables were mainly from the inputs of chemical fertilizer and organic fertilizer,respectively.However,the inputs of chemical fertilizer and organic fertilizer both significantly affected the phosphorus surplus in the orchard production system.展开更多
In order to explore the soil nutrient characteristics and put forward the improvement measures, a field experiment was arranged and performed. The experiment was conducted to evaluate the pH value and primary nutrient...In order to explore the soil nutrient characteristics and put forward the improvement measures, a field experiment was arranged and performed. The experiment was conducted to evaluate the pH value and primary nutrient status in blueberry garden soil by means of collecting 21 soil samples from the main production base of blueberries in Qingdao, according to the specific requirements of blueberries for soil pH and organic matter and the second national soil survey nutrient classification standard. Results showed that the blueberry garden soil had the following characteristics: acidic soil, low organic matter content with significant differences among different bases, moderate total nitrogen and alkaline hydrolysis nitrogen contents, high available phosphorus content and above moderate available potassium content. Then, it is found that the primary causes were the differences in soil basic fertility, excessive use of sulfur, inadequate inputs of organic matter, not thorough soil improvement, and imperfect fertilizer management in the blueberry gardens. Finally, the corresponding improvement measures were put forward, for example, increasing organic fertilizer and organic matter covering, as well as the application of CaCO_3 and formulated fertilization.展开更多
The objective of this paper relies on the establishment of the sampling moment and the nutritional state of the species Conilon coffee (Coffea canephora) cultivated in Cambisoils. The effect of different rates of ni...The objective of this paper relies on the establishment of the sampling moment and the nutritional state of the species Conilon coffee (Coffea canephora) cultivated in Cambisoils. The effect of different rates of nitrogen fertilization was also studied in the leaves concentrations of N, at randomized complete block designs (N0= 0; N1 = 50; N2 = 100; N3 = 150 and N4 = 200 kg.ha^-1 of N) in presence of P (40 kg.ha^-1 of P2O5) and K (160 kg.ha^-1 of K2O), with four replicates. The samples were carried out in the months of March (flower blossoming stage), June (fruits growing stage), September (grain development) and December (maturation) in all treatments. Foliar analysis carried out in the month of June (fruits growing stage) for the purpose of establishing critical nutrient range values for N, settling down approaches of interpretation of the same one for the Conilon coffee plantations on Cambisoils. The biggest percentages in the yields are obtained with leaves containing N between 2.80% and 3.10%, a value below 2.80% N which they associated with indicative percentages of stable maximum yield that did not surpass the limits of the adequate nutrients supply.展开更多
Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growt...Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growth, yield, and fruit quality(protein, Vitamin C, nitrates, organic acid and soluble sugar) of tomato were studied keeping concentrations of other nutrients unchanged in the nutrient solution. The results showed that parameters related to the growth of tomato(plant height and Stem diameter), changes of tomato yield per plant and quality of tomato fruits were the highest when the plants were grown at 20% Ca treatments. In the second study, increased EC concentrations of nutrient solution resulted in stronger plants with improved yields and quality. Four different concentration gradients of nutrient solution treatment were designed based on the results of the first research stage(EC=1.5, 2.5, 3.5, 4.5 m S/cm, respectively). The single tomato plant had the highest production which is 2 268.994 g/plant, when the nutrient solution strength was at EC=1.5 m S cm, whereas they have the best fruit quality when the solution strength at EC 4.5 m S/cm. This suggests the need for wide popularization of the nutrient solution formula in large areas to improve the tomato production.展开更多
基金Supported by Science&Technology Support for Xinjiang(201191143)Special Fund for Xinjiang Water Conservancy Science&Technology(2013T04,2013T05)Key Laboratory of Construction Project of Xinjiang Academy of Agricultural Sciences(xjnkkl-2013-001)~~
文摘The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation.
基金Supported by Sino-Germany Cooperation Project (BMBF FKZ:0330847B,MOST:2009DFA32710)Public Welfare Industry Special Item of Ministry of Agriculture (200803030)~~
文摘[Objective] The research aimed to evaluate the phosphorus balances in the main crop production systems in Shunyi District of Beijing City.[Method] By using the nutrient budget method,the phosphorus balances in the main crop production systems(field crops,orchard and open-field vegetables) in Shunyi District of Beijing City were evaluated.Moreover,the main influence elements of phosphorus surplus in the farmland were analyzed.[Result] The positive phosphorus balances were found across all three crop production systems in the study period.The amount of phosphorus surplus [491.8 kg/(hm2·a)] in vegetables production system was significantly higher than that in field crops [82.7 kg/(hm2·a)] and orchard [129.5 kg/(hm2·a)] production systems(P0.05).But the amount of phosphorus surplus between the latter two had no significant difference(P0.05).Phosphorus surpluses in the production systems of field crops and vegetables respectively presented the extremely significant and positive relationship with the phosphorus input from chemical fertilizer and organic fertilizer(r was respectively 0.987 7 and 0.970 1).The phosphorus input from chemical fertilizer and organic fertilizer in the orchard production system both presented the extremely significant and positive relationship with the phosphorus surplus in the farmland(r was respectively 0.836 3 and 0.625 2).However,the phosphorus harvested by crops didn't significantly correlated to the phosphorus surplus in the farmland for all three crop production systems(P0.05).[Conclusion] The risk of phosphorus pollution potential in all three crop production system of Shunyi Distirct was high,especially in the vegetable production system.The phosphorus surpluses in the production systems of field crops and vegetables were mainly from the inputs of chemical fertilizer and organic fertilizer,respectively.However,the inputs of chemical fertilizer and organic fertilizer both significantly affected the phosphorus surplus in the orchard production system.
基金Supported by Forestry Industry Research Special Funds for Public Welfare Projects(201204402)Spark Program(2014GA741014)Qingdao"Little Blue Big Man"Planning Program(2014GA741014)~~
文摘In order to explore the soil nutrient characteristics and put forward the improvement measures, a field experiment was arranged and performed. The experiment was conducted to evaluate the pH value and primary nutrient status in blueberry garden soil by means of collecting 21 soil samples from the main production base of blueberries in Qingdao, according to the specific requirements of blueberries for soil pH and organic matter and the second national soil survey nutrient classification standard. Results showed that the blueberry garden soil had the following characteristics: acidic soil, low organic matter content with significant differences among different bases, moderate total nitrogen and alkaline hydrolysis nitrogen contents, high available phosphorus content and above moderate available potassium content. Then, it is found that the primary causes were the differences in soil basic fertility, excessive use of sulfur, inadequate inputs of organic matter, not thorough soil improvement, and imperfect fertilizer management in the blueberry gardens. Finally, the corresponding improvement measures were put forward, for example, increasing organic fertilizer and organic matter covering, as well as the application of CaCO_3 and formulated fertilization.
文摘The objective of this paper relies on the establishment of the sampling moment and the nutritional state of the species Conilon coffee (Coffea canephora) cultivated in Cambisoils. The effect of different rates of nitrogen fertilization was also studied in the leaves concentrations of N, at randomized complete block designs (N0= 0; N1 = 50; N2 = 100; N3 = 150 and N4 = 200 kg.ha^-1 of N) in presence of P (40 kg.ha^-1 of P2O5) and K (160 kg.ha^-1 of K2O), with four replicates. The samples were carried out in the months of March (flower blossoming stage), June (fruits growing stage), September (grain development) and December (maturation) in all treatments. Foliar analysis carried out in the month of June (fruits growing stage) for the purpose of establishing critical nutrient range values for N, settling down approaches of interpretation of the same one for the Conilon coffee plantations on Cambisoils. The biggest percentages in the yields are obtained with leaves containing N between 2.80% and 3.10%, a value below 2.80% N which they associated with indicative percentages of stable maximum yield that did not surpass the limits of the adequate nutrients supply.
文摘Tomato seedlings were grown in substrate culture with pots. The formulation of Holland Greenhouse Horticulture Research Institute was used(as CK) and the effects of different Ca concentrations(LCa, CK and HCa)on growth, yield, and fruit quality(protein, Vitamin C, nitrates, organic acid and soluble sugar) of tomato were studied keeping concentrations of other nutrients unchanged in the nutrient solution. The results showed that parameters related to the growth of tomato(plant height and Stem diameter), changes of tomato yield per plant and quality of tomato fruits were the highest when the plants were grown at 20% Ca treatments. In the second study, increased EC concentrations of nutrient solution resulted in stronger plants with improved yields and quality. Four different concentration gradients of nutrient solution treatment were designed based on the results of the first research stage(EC=1.5, 2.5, 3.5, 4.5 m S/cm, respectively). The single tomato plant had the highest production which is 2 268.994 g/plant, when the nutrient solution strength was at EC=1.5 m S cm, whereas they have the best fruit quality when the solution strength at EC 4.5 m S/cm. This suggests the need for wide popularization of the nutrient solution formula in large areas to improve the tomato production.