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Determination of climatic predictors influencing seed production in seed orchards of Korean red pine based on different regression models
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作者 Yong-Yul Kim Ja-Jung Ku +4 位作者 Hyo-In Lim Sung-Ryul Ryu Ji-Min Park Ye-Ji Kim Kyu-Suk Kang 《Journal of Forestry Research》 2025年第2期78-87,共10页
Pinus densiflora is a pine species native to the Korean peninsula,and seed orchards have supplied mate-rial needed for afforestation in South Korea.Climate vari-ables affecting seed production have not been identified... Pinus densiflora is a pine species native to the Korean peninsula,and seed orchards have supplied mate-rial needed for afforestation in South Korea.Climate vari-ables affecting seed production have not been identified.The purpose of this study was to determine climate variables that influence annual seed production of two seed orchards using multiple linear regression(MLR),elastic net regres-sion(ENR)and partial least square regression(PLSR)mod-els.The PLSR model included 12 climatic variables from 2003 to 2020 and explained 74.3%of the total variation in seed production.It showed better predictive performance(R2=0.662)than the EN(0.516)and the MLR(0.366)mod-els.Among the 12 climatic variables,July temperature two years prior to seed production and July precipitation after one year had the strongest influence on seed production.The time periods indicated by the two variables corresponded to pollen cone initiation and female gametophyte development.The results will be helpful for developing seed collection plans,selecting new orchard sites with favorable climatic conditions,and investigating the relationships between seed production and climatic factors in related pine species. 展开更多
关键词 Pinus densiflora Seed production Seed orchard Climatic factors Partial least squares regression
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Effects of Soybean Intercropping on Soil N,P and K Elements in High-quality Peach Orchards
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作者 Yinhong WANG Xiong YAN +6 位作者 Shilan LI Wenzhao LI Kai HUANG Dan LIU Pingfan WU Jun CHENG Detao YU 《Agricultural Biotechnology》 2025年第5期19-21,共3页
[Objectives]This study was conducted to investigate the impact of soybean intercropping on soil fertility in the planting areas of high-quality peach orchards in Shenxi Town,Zunyi City,Guizhou Province.[Methods]Soil s... [Objectives]This study was conducted to investigate the impact of soybean intercropping on soil fertility in the planting areas of high-quality peach orchards in Shenxi Town,Zunyi City,Guizhou Province.[Methods]Soil samples were collected during the seedling,growth,and maturity stages of soybeans from both non-intercropped soil(control check group,CK)and soybean-intercropped soil(Qiandou 11,experimental group,EK).Analysis was conducted on soil fertility properties,including alkali-hydrolyzable N,available P,and available K.[Results]The impact of soybean intercropping on soil physicochemical properties was primarily manifested as the increased levels of alkali-hydrolyzable N and available K and the decreased level of available P in the soil during the seedling,growing,and maturity stages.Overall,this approach optimized and enhanced soil fertility in the peach orchards,providing a viable pathway for soil improvement in peach orchards located in karst areas.[Conclusions]The findings of this study provide a scientific basis for the high-quality development of high-quality peach orchards. 展开更多
关键词 Soybean intercropping High-quality peach orchard Soil fertility
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Bioremediation of Soil Pollution in Orchard 被引量:6
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作者 王宝申 王炳华 +4 位作者 高树青 刘秀春 高艳敏 陈宝江 杨华 《Agricultural Science & Technology》 CAS 2009年第5期154-157,共4页
[ Objective ] The aim was to study the bioremediation mechanism of soil pollution. [ Method ] The effects of applying biological organic fertilizers on the bioremediation of soil pollution in orchard were studid by ex... [ Objective ] The aim was to study the bioremediation mechanism of soil pollution. [ Method ] The effects of applying biological organic fertilizers on the bioremediation of soil pollution in orchard were studid by experiment in orchard field and soil simulative experiment. [ Result] The biological organic fertilizers improved the activities of enzymes like polyphenol oxidase, urease, phosphatase, etc. in root-zone soil, promoted the passivation of heavy metals like Cd^2+ , Pb^2+ , Cr^3+ , As^8+ , etc. in root-zone soil, increased the quantities of useful active bacterium like beneficial fungi, actinomycetes, bacterium, etc. and decreased the quantities of harmful biology (like Fusarium oxysporum, Moniliophthora roreri, Ruselliniu necutrix/Helicobasidium mompa, nematode, etc. [ Conclusion] The study results provide some references for the popularization and application of biological organic fertilizers on fruit trees. 展开更多
关键词 orchard soil BIOREMEDIATION Biological organic fertilizers
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Analysis of Soil Degradation Causes in Orchards with Different Planting Years 被引量:5
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作者 王治国 付彦博 +3 位作者 饶晓娟 耿庆龙 孟阿静 冯耀祖 《Agricultural Science & Technology》 CAS 2014年第8期1331-1334,共4页
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
关键词 orchard Soil degradation Soil available nutrient Trace element in soil
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Research Advance on Sod Culture in Peach Orchard 被引量:1
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作者 白瑞霞 王越辉 +1 位作者 马之胜 贾云云 《Agricultural Science & Technology》 CAS 2017年第2期270-273,284,共5页
Sod culture in peach orchards is an advanced soil management. The significances of sod culture in peach orchard are introduced, as well as the sod ways. The effects of sod culture in a peach orchard on soil, microclim... Sod culture in peach orchards is an advanced soil management. The significances of sod culture in peach orchard are introduced, as well as the sod ways. The effects of sod culture in a peach orchard on soil, microclimate and growth and development of peach tree, and disease, pest and weed are reviewed. The problems in sod culture in peach orchard in China are summarized. Sod culture could increase soil fertility, improve soil physical properties, relieve soil temperature change, increase soil microbial growth and soil enzyme activity, improve microclimate and fruit quality, reduce physiological disease, insect pests and weeds. 展开更多
关键词 Sod culture in peach orchard PEACH SOIL MICROCLIMATE Growth and development Physiological disease pest and weed
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Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler Irrigation 被引量:15
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作者 Ali Asghar Ghaemi Mohammad Rafie Rafiee Ali Reza Sepaskhah 《Agricultural Sciences in China》 CSCD 2009年第1期98-107,共10页
Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran (a 0.17 ha peach orchard and a 0.24 ha orange orchard) to protect peach b... Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran (a 0.17 ha peach orchard and a 0.24 ha orange orchard) to protect peach blossoms and orange trees leaves and fruits from low temperature damage. The experiment used a system that monitored the trees and air temperatures using two thermistors. The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO, In the peach orchard, the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004. The system successfully kept peach flowers above the critical temperature, i.e., -4.0℃ in spring 2004 (control block -4.12℃, and sprinkled block +0.5℃) during all events. Similar results were obtained in the orange orchard during three frost events in the winter of 2004, during which the tree temperatures were at least 2.5℃ above the critical temperature. Results from field tests show that the system can effectively protect the peach blossoms from damage. Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill. Calculations indicated that when using variable application rates, the amount of water used can be reduced by 54.3%. Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom, Iran. Results showed a significant temperature control in the experimental block, especially in the central part of the orchard, but the block margins (about 3.6% of the total area) were at the risk of low temperature due to the wind drift effects. 展开更多
关键词 AUTOMATED sprinkler irrigation FROSTPORO frost protection peach orchard orange orchard
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Phenological observations on Larix principis-rupprechtii Mayr. in primary seed orchard 被引量:7
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作者 张新波 任建茹 张旦儿 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期201-204,210,共4页
Through 5 years of phenological observations on Larix principis-rupprechtii Mayr. in primary seed orchard and studies on population and individuals of clones, the annual periodic phenological laws were revealed and th... Through 5 years of phenological observations on Larix principis-rupprechtii Mayr. in primary seed orchard and studies on population and individuals of clones, the annual periodic phenological laws were revealed and the annual phe-nological periodic table was drawn up. The correlation between various phenophases, the air temperature and active accumu-lated temperature were analyzed and expounded. The authors also analyzed the similarities and differences of phenophases among clonal individuals as well as the blooming properties of male and female flowers at the same time. This study could pro-vide theoretical reference for working out the production plan of improved varieties and other management measures in seed orchard of Larix principis-rupprechtii. 展开更多
关键词 Larix principis-rupprechtii Mayr. Primary seed orchard Phenological observation
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Structure Parameters and Physiological Indices Research of High-quality and High-yield Apple Orchards 被引量:2
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作者 薛晓敏 王翠玲 +2 位作者 王金政 孟海凤 聂佩显 《Agricultural Science & Technology》 CAS 2014年第11期1953-1956,1959,共5页
In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of ap... In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively. 展开更多
关键词 High-quality and high-yield Apple orchard Structure parameters Physio-logical index
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Influences of Seasonal Freezing and Thawing on Soil Water-stable Aggregates in Orchard in High Cold Region,Northeast China 被引量:4
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作者 LIANG Yunjiang DENG Xu +4 位作者 SONG Tao CHEN Guoshuang WANG Yuemei ZHANG Qing LU Xinrui 《Chinese Geographical Science》 SCIE CSCD 2021年第2期234-247,共14页
Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of ... Soil aggregate stability,as an important indicator of soil functions,may be affected by seasonal freezing and thawing(SFT)and land use in high cold and wet regions.Therefore,comprehensive understanding the effects of SFT on aggregate stability in orchards during winter and spring is crucial to develop appropriate management strategies that can effectively alleviate the degradation of soil quality to ensure sustainable development of orchard ecosystems.To determine the mechanism of degradation in orchard soil quality,the effects of SFT on the stability of water-stable aggregates were examined in apple-pear orchards(Pyrus ussuriensis var.ovoidea)of four different ages(11,25,40,and 63 yr)on 0 to 5%slopes before freezing and after thawing from October 2015 to June 2016 in Longjing City,Yanbian Prefecture,Northeast China,involving a comparison of planted versus adjacent uncultivated lands(control).Soil samples were collected to investigate water-stable aggregate stability in three incremental soil layers(0–20,20–40 and 40–60 cm).In the same samples,iron oxide,organic matter,and clay contents of the soil were also determined.Results showed that the destructive influences of SFT on water-stable aggregates were more pronounced with the increased orchards ages,and SFT exerted severe effects on water-stable aggregates of older orchards(40 and 63 yr)than juvenile orchards.Undergoing SFT,the soil instability index and the percentage of aggregate destruction increased by mean 0.15 mm and 1.86%,the degree of aggregation decreased by mean 1.32%,and the erosion resistance weakened,which consequently led to aggregate stability decreased.In addition,soil free,amorphous,and crystalline iron oxide as well as soil organic matter and clay contents are all important factors affecting the stability of water-stable aggregates,and their changes in their contents were consistent with those in the stability of water-stable aggregates.The results of this study suggest that long-term planting fruit trees can exacerbate the damaging effects of SFT on aggregate stability and further soil erosion increases and nutrient losses in an orchard,which hider sustainable use of soil and the productivity orchards. 展开更多
关键词 water-stable aggregates orchard age apple-pear orchard soil seasonal freezing and thawing soil degradation high cold region
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Mulch Grasses Planting and Management Techniques in Orchards of Southern China Based on Different Utilization Purposes 被引量:3
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作者 LI Chang-jun PENG Hua +5 位作者 XIE Yun-he ZHU Jian LI Sheng-nan JIAN Yan WEI wei JI Xiong-hui 《Agricultural Science & Technology》 CAS 2019年第4期20-29,共10页
Planting mulch grasses in orchards,as a technique to build ecological orchards,can be one of the strategic approaches for rural revitalization.This study sorted out the common varieties of mulch grasses and analyzed t... Planting mulch grasses in orchards,as a technique to build ecological orchards,can be one of the strategic approaches for rural revitalization.This study sorted out the common varieties of mulch grasses and analyzed their application statuses in orchards of southern China.According to different utilization purposes of mulch grasses in orchards,scientific suggestions were given from aspects of grass selection,cultivation techniques,management methods and use modes.The study will provide reference for the construction of ecological orchards in southern China. 展开更多
关键词 Southern orchard Mulch grasses planting Mulch grasses selection Ecological orchards construction
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Nitrification and Denitrification Activities and N_2O Emission of Orchard Soils Cultivated for Different Periods of Time
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作者 张玉树 丁洪 +3 位作者 胡晓霞 张生才 秦胜金 郑祥洲 《Agricultural Science & Technology》 CAS 2012年第4期843-848,共6页
[Objective] The aim was to investigate the differences in nitrification and denitrification activities and the N20 emission of orchard soils cultivated for different periods of time. [Method] Incubation experiment was... [Objective] The aim was to investigate the differences in nitrification and denitrification activities and the N20 emission of orchard soils cultivated for different periods of time. [Method] Incubation experiment was conducted to determine the ni- trification and denitrification activities and N20 emission of three types of orchard soil samples that had been cultivated for 5, 12 and 20 years, respectively, by using the virgin soil sample as control. [Result] After 26 d of incubation, the nitrification rates of nitrogen fertilizer in the virgin soil sample and the orchard soil samples cultivated for 5, 12 and 20 years were 6.85%, 10.26%, 13.29% and 12.90%, respectively, which were positively correlated with content of soil organic matter, ammonium nitro- gen and total nitrogen (P〈0.05), and negatively correlated with soil carbon-nitrogen ratio and pH value (P〈0.05). The denitrification activities of these soil samples in- creased with the increase of cultivation years. The amount of nitrogen loss by deni- trification accounted for 0.01%-3.11% of the amount of fertilizer nitrogen, and had a positive correlation with the content of soil organic matter (P〈0.05). The N20 emis- sions of orchard soil samples were higher than that of the virgin soil samples (P〈 0.05). [Conclusion] In South China, the nitrification activity of orchard soil is relatively low, but it has a tendency to increase as the cultivation years increases; the denitri- fication activity is relatively high, and increases significantly with the increase of culti- vation years. 展开更多
关键词 orchard soil NITRIFICATION DENITRIFICATION N2O emission
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Control Effects of Several Technical Measures on Overwintering Generation of Oriental Fruit Moth in Peach Orchard
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作者 王越辉 白瑞霞 +3 位作者 马之胜 贾云云 李海山 马铭泽 《Agricultural Science & Technology》 CAS 2016年第5期1177-1180,共4页
Peeling trunk,binding insect-attracting belt,cleaning orchard and soil-covering under the crown were the control methods on overwintering generation of oriental fruit moth.However,they had not been applied widely on t... Peeling trunk,binding insect-attracting belt,cleaning orchard and soil-covering under the crown were the control methods on overwintering generation of oriental fruit moth.However,they had not been applied widely on the production because of the lack of systematic quantitative evaluation.Aiming at this fact,the control effects of these technical measures were studied in peach with different ripening period.The results showed that peeling trunk was the best with the control effect of88.64%.The control effect of binding insect-attracting belt of grass bundle was74.13%,which was the most economical and efficient.Covering with soil layer of 3cm under the crown during the middle ten days of March could holdback the adult getting out from soil.Cleaning deadwood could clean out the overwintering larvae on the ground. 展开更多
关键词 Peach orchard Oriental fruit moth Overwintering generation Control method
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Preliminary Study on the Mechanization Demand of Orchards in North China
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作者 Lifeng XUAN Shuaike NIU +6 位作者 Jianguo WEI Zhan CHEN Dongfeng YANG Shulin WANG Lejun CUI Guanghai WANG Lili YANG 《Asian Agricultural Research》 2022年第8期44-45,59,共3页
From the production management practice of fruit trees in North China by agricultural research institutions,combining the relevant national policies and documents in recent years,the demand for orchard machinery in fr... From the production management practice of fruit trees in North China by agricultural research institutions,combining the relevant national policies and documents in recent years,the demand for orchard machinery in fruit tree production of North China is summarized,and preliminary thoughts and suggestions are put forward.It could promote the joint of machinery and agriculture(industry,university,research and application departments),and improve mechanization level of orchards in North China. 展开更多
关键词 orchard mechanization orchard management Mechanization demand
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Effect of lime application on microbial community in acidic tea orchard soils in comparison with those in wasteland and forest soils 被引量:21
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作者 Dong Xue Xiangdong Huang +1 位作者 Huaiying Yao Changyong Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第8期1253-1260,共8页
Lime application is a conventional technology to control acidification in tea orchard soils. We investigated the effect of lime application on soil microbial community diversity in the soils of three tea orchards, was... Lime application is a conventional technology to control acidification in tea orchard soils. We investigated the effect of lime application on soil microbial community diversity in the soils of three tea orchards, wasteland and forest. The BIOLOG data showed that both the average well color development of all carbon sources and the functional diversity index increased with the liming rate in the tea orchards and the forest, but decreased in the wasteland. The phospholipid fatty acid (PLFA) analysis showed that the structural diversity index of soil microbial community increased with the liming rate in all the tea orchards, the wasteland and the forest. Lime application also increased the soil-bacterial PLFA content in all the soils. Soil fungal and actinomycete PLFAs in the tea orchards showed an increasing trend from 0 to 3.2 g CaCO 3 /kg application and then a decreasing trend from 3.2 to 6.4 g CaCO 3 /kg application. The principal component analysis of BIOLOG and PLFA data suggested that lime application had a significant effect on soil microbial community structure, and land use had a greater effect on soil microbial community structure compared to lime application. 展开更多
关键词 microbial community diversity phospholipid fatty acid LIME tea orchard soil
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Nitrification potentials of Chinese tea orchard soils and their adjacent wasteland and forest soils 被引量:12
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作者 XUE Dong GAO Yangmei +1 位作者 YAO Huaiying HUANG Changyong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第9期1225-1229,共5页
To investigate the nitrifying activities of different soil types, soil samples collected from 8-, 50- and 90-year old tea orchards, the adjacent wasteland, and 90-year old forest were measured for their nitrification ... To investigate the nitrifying activities of different soil types, soil samples collected from 8-, 50- and 90-year old tea orchards, the adjacent wasteland, and 90-year old forest were measured for their nitrification potentials using the conventional soil incubation and the liquid incubation method. Among different soil types, the nitrification potential of soil in tea orchards was higher than that of wasteland and forest soils. The slurry shaken liquid incubation method was confirmed to be more accurate and have reliable results than the soil incubation. Interestingly, experimental result revealed that the generally applied pH value of 7.2 for the liquid media was not the optimal pH for these acid soils with a strong buffer capacity. This suggested that tea orchard soils may have nitrifiers requiring pHneutral condition for the best activity. Our data also showed that treatment with the commonly used nitrogen fertilizer urea significantly improved nitrification potential of the soils; such enhancement effect was stronger on all of three tea orchard soils than on wasteland and forest soils, and also stronger on the younger (8- and 50-year old) tea orchard soils than on the older one (90-year old). 展开更多
关键词 tea orchard WASTELAND forest nitrification potential UREA
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Spatial Distribution of Soil Organic Matter and Nutrients in the Pear Orchard Under Clean and Sod Cultivation Models 被引量:12
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作者 XU Ling-fei ZHOU Peng +3 位作者 HAN Qing-fang LI Zhi-hui YANG Bao-ping NIE Jun-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第2期344-351,共8页
The soil organic matter and nutrients are fundamental for the sustainability of pear production, but little is known about the spatial distribution of soil organic matter and nutrients in a pear orchard. With the soil... The soil organic matter and nutrients are fundamental for the sustainability of pear production, but little is known about the spatial distribution of soil organic matter and nutrients in a pear orchard. With the soil of the pear (cv. Dangshansu on P.betulifolia Bunge. rootstock) orchard under clean and sod cultivation models as test materials, the experiment was conducted to evaluate spatial variability of soil organic matter (SOM), total nitrogen (STN), total phosphorus (STP), total potassium (STK), available nitrogen (SAN), and available potassium (SAK) in and between rows at different soil depths (0-60 cm). The SOM, STN, STP, STK, SAN and SAK of the different soil layers under the two tillage models were different in the vertical direction. The SOM, STN, STP and SAN in the 0-20 cm soil layer were higher than those in the 20-40 and 40- 60 cm soil layers. The STK of 40-60 cm soil layer was higher than that in the 0-20 and 20-40 cm soil layers. The STK increased with the depth of soil in the vertical direction in the clean cultivated pear orchard. Variability of the SOM, STN, STP, STK, SAN and SAK of sample sites in between rows of the same soil layer was found in the pear orchard soil in the horizontal direction under clean and sod cultivation management systems, except that STK of all sites did not show the difference in identical soil layers in the pear orchard under clean cultivation. The sod cultivation model improved the SOM, STN, and STK in the 0-20 cm soil layer in the pear orchard, and the three components increased by 12.8, 12.7 and 7.3% compared to clean cultivation, respectively. The results can be applicable to plan collection of orchard soil samples, assess orchard soil quality, and improve orchard soil management practices. 展开更多
关键词 spatial distribution soil organic matter soil nutrients clean cultivation sod cover pear orchard
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Scheme of Weather-Based Indemnity Indices for Insuring Against Freeze Damage to Citrus Orchards in Zhejiang,China 被引量:12
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作者 LOU Wei-ping QIU Xin-fa +3 位作者 WU Li-hong NI Hu-ping TANG Qi-yi MAO Yu-ding 《Agricultural Sciences in China》 CAS CSCD 2009年第11期1321-1331,共11页
We design a weather-based indemnity index for the insurance against freeze damage to citrus orchards so as to provide technological support for the development of policy-based agriculture. The indices are prepared by ... We design a weather-based indemnity index for the insurance against freeze damage to citrus orchards so as to provide technological support for the development of policy-based agriculture. The indices are prepared by separating a relative meteorological yield from the yield that is dependent on tree age, high-yield and low-yield years, and environmental factors, and then using a risk assessment scheme to determine the percentage yield reduction due to the meteorological hazard. We thus develop a set of indices associated with cold temperature damage with which to construct more severe weather indices in conjunction with the yield percentage decrease. We then combine the insured regional citrus yield index with the insured meteorological counterpart to obtain a weather-based indemnity index for the varying degree of freeze damage to crops. When the freeze damage index (FDI) is greater than -7.0℃ for the coastal belt of Zhejiang Province, China, or greater than -9.0℃ for other regions of Zhejiang, weather-based indemnity index (WBII) is zero, meaning there is no compensation; when the FDI is from -7.0 to -7.9℃ for the coastal belt or from -9.0 to -9.9℃ for other regions, the WBII is 1 with 50% compensation; when the FDI is from -8.0 to -8.9℃ for the coastal belt or from -10.0 to -10.9℃ for other regions, the WBII is 2 with 70% compensation; and when the FDI is less than -9.0℃ for the coastal belt or less than -11.0℃ for other regions, the WBII is 3 with 90% compensation. The weather indemnity indices of insured orchards are developed in the interest of owners, thereby eliminating adverse selection and moral hazard issues and providing timely recompense from the insurer, and resolving the problem of high indemnity cost in agricultural insurance. 展开更多
关键词 citrus orchard freeze damage agricultural insurance weather-based indemnity index
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Reducing nitrogen fertilization of intensive kiwifruit orchards decreases nitrate accumulation in soil without compromising crop production 被引量:9
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作者 LU Yong-li KANG Ting-ting +2 位作者 GAO Jing-bo CHEN Zhu-jun ZHOU Jian-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1421-1431,共11页
Excessive nitrogen (N) fertilization of high value horticultural crops is a common problem that not only increases the cost to farmers, but also negatively affects crop growth and the environment. A three-year field... Excessive nitrogen (N) fertilization of high value horticultural crops is a common problem that not only increases the cost to farmers, but also negatively affects crop growth and the environment. A three-year field experiment was conducted in an intensive kiwifruit orchard in Shaanxi Province, China to compare the effects of reduced N fertilization applied as urea (U), and controlled release urea (CRU) on the N nutrition of kiwi vines, fruit yield and quality, and nitrate-N accumulation in the soil profile. The three treatments included a conventional N application rate (CF-U, 900 kg N ha-1 yr-1 as urea), two reduced N fertilization treatments where the amount of N fertilizer applied as U and CRU was reduced by 25% in 2013 and 2014, and by 45% in 2015. The 25 and 45% reduced N treatments had no adverse effects on the N concentrations in leaves and pruning branches and the fruit yield and quality of kiwi vines. However, they significantly enhanced the partial factor productivity of applied N (PFPN) and the economic benefits, and reduced nitrate accumulation in the 0-200 cm soil profile. The same benefits of reduced N fertilization were observed for both the U and CRU treatments, but the CRU treatment had the added benefit of decreasing the loss of nitrate through leaching. We concluded that the current level of N fertilization in kiwi orchards is very excessive, and reducing the N fertilizer rate by 25-45% could not only guarantee fruit yield, but also reduce N accumulation and loss. 展开更多
关键词 kiwifruit orchard fruit yield and quality nitrate accumulation controlled release urea (CRU)
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Soil Fertility,Microbial Biomass,and Microbial Functional Diversity Responses to Four Years Fertilization in an Apple Orchard in North China 被引量:21
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作者 Zhanling Zhu Yan Bai +5 位作者 Minglu Lv Ge Tian Xin Zhang Li Li Yuanmao Jiang Shunfeng Ge 《Horticultural Plant Journal》 SCIE 2020年第4期223-230,共8页
Soil microbial communities play an essential role in maintaining soil fertility and are considered as ecological indicators to evaluate soil health.In the present study,we examined the influence of almost 4 years of f... Soil microbial communities play an essential role in maintaining soil fertility and are considered as ecological indicators to evaluate soil health.In the present study,we examined the influence of almost 4 years of fertilization[no fertilizer(CK),nitrogen alone(N),nitrogen,phosphorus and potassium chemical fertilizer(NPK),organicmanure(M),nitrogen plus organic manure(NM),and NPK plus organic manure(NPKM)]on soil fertility and the functional diversity of soil microbial communities in an apple orchard.Compared to CK,fertilization increased soil organic carbon,total nitrogen,and available nutrients,but reduced soil pH in N and NPK treatments.The highest microbial biomass carbon and nitrogen,most probable number of actinomycetes,bacteria,and fungi occurred in the NPKM treatment.The average well color development(AWCD)values followed the order of NPKM>M>NPK and NM>CK and N.The Shannon index in organic manure treatments were significantly higher than in control and in treatments without organic manure.The principal component analysis showed that manure treatment was significantly separated from other treatments.These results indicated that organic manure applied alone or in combination with chemical fertilizers would increase soil fertility and functional diversity of soil microbial communities.Moreover,applying balanced N,P,K fertilizer in combination with organic manure was found to be superior to the use of a single fertilizer in improving soil microbial community quality. 展开更多
关键词 apple orchard FERTILIZATION soil fertility soil microbial community functional diversity
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Temporal Variability in Soil CO_2 Emission in an Orchard Forest Ecosystem 被引量:10
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作者 LI Yue-Lin D. OTIENO +4 位作者 K. OWEN ZHANG Yun J. TENHUNEN RAO Xing-Quan LIN Yong-Biao 《Pedosphere》 SCIE CAS CSCD 2008年第3期273-283,共11页
Temporal variability in soil CO2 emission from an orchard was measured using a dynamic open-chamber system for measuring soil CO2 effiux in Heshan Guangdong Province, in the lower subtropical area of China. Intensive ... Temporal variability in soil CO2 emission from an orchard was measured using a dynamic open-chamber system for measuring soil CO2 effiux in Heshan Guangdong Province, in the lower subtropical area of China. Intensive measurements were conducted for a period of 12 months. Soil CO2 emissions were also modeled by multiple regression analysis from daily air temperature, dry-bulb saturated vapor pressure, relative humidity, atmospheric pressure, soil moisture, and soil temperature. Data was analyzed based on soil moisture levels and air temperature with annual data being grouped into either hot-humid season or relatively cool season based on the precipitation patterns. This was essential in order to acquire simplified exponential models for parameter estimation. Minimum and maximum daily mean soil CO2 effiux rates were observed in November and July, with respective rates of 1.98 ± 0.66 and 11.04 ± 0.96 μmol m^-2 s^-1 being recorded. Annual average soil CO2 emission (FCO2) was 5.92 μmol m^-2 s^-1. Including all the weather variables into the model helped to explain 73.9% of temporal variability in soil CO2 emission during the measurement period. Soil CO2 effiux increased with increasing soil temperature and soil moisture. Preliminary results showed that Q10, which is defined as the difference in respiration rates over a 10 ℃ interval, was partly explained by fine root biomass. Soil temperature and soil moisture were the dominant factors controlling soil CO2 effiux and were regarded as the driving variables for CO2 production in the soil. Including these two variables in regression models could provide a useful tool for predicting the variation of CO2 emission in the commercial forest Soils of South China . 展开更多
关键词 CO2 emission lower subtropical area orchard forest ecosystem soil moisture soil temperature
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