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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Studying the soil stoichiometric ratios and the influencing factors of different altitude gradients in mountain ecosystems in arid zones is significant in revealing the soil nutrient status and maintaining the sustainable development of mountain ecosystems. In this paper, 13 sample plots were established along the elevation gradient in the mountains of the southern Ili River Valley, and soil in the depth of 0-20 cm was studied to investigate nutrient stoichiometric ratios and their influencing factors. The results showed that: (1) Soil acidity gradually increased with elevation. Organic carbon and total nitrogen contents are significantly higher in the middle and high mountain belts than in the low mountain belts, while total phosphorus and total potassium contents are opposite. (2) Due to altitudinal differences, the carbon-to-nitrogen ratio is significantly higher in the mid-alpine belt than in the low and alpine belts; carbon and phosphorus ratios are significantly higher in the middle and high mountain belts than in the middle and low mountain belts; carbon and potassium ratios are significantly higher in the middle and high mountain belts than in the low mountain belts; nitrogen-phosphorus ratios are higher in the alpine zone, but there is no major difference between the transition zone and the low mountain zone; nitrogen-potassium ratios are much higher in the alpine zone, whereas there is no significant difference between the mid-alpine zone and the transition zone; the differences of phosphorus/potassium ratios between altitudinal gradients are ignorable. (3) The dominant factors affecting the stoichiometric ratios of soil physicochemical indicators are soil organic carbon (62.4%), total phosphorus (15.9%), and total carbon (13.7%); while the major environmental factors are mean annual soil temperature (27.1%), vegetation index (11.2%), elevation (12.3%), and mean annual atmospheric temperature (3.4%). The study showed that the physicochemical indicators have an important influence on the soil stoichiometric ratio, further verified that the altitude is still the dominant factor affecting the stoichiometric ratio, and revealed that the influence of microenvironmental factors on the soil stoichiometric ratio should not be neglected, which provides a scientific basis for the in-depth study of the nutrient status of soils in mountainous areas of the Ili River Valley. [ABSTRACT FROM AUTHOR]

[Objective] Rock fragments are ubiquitous in soil, especially in arid and semi-arid regions. They have a considerable influence on various subsurface hydrological processes. Understanding the impact of rock fragments on these processes is crucial for improving water resource management, ecosystem restoration and sustainable development. [Method] This paper reviews the research over the past decades on the influence of rock fragments on subsurface hydrological processes, highlighting the challenges and limitations we currently face and proposing potential research perspectives. Specifically, we analyze the effects of characteristic parameters of rock fragments, such as their coverage, content, and size, on water infiltration, surface runoff and subsurface flow, preferential flow and soil evaporation. We also review progress in mathematical models used to simulate and quantify the effects of rock fragments on subsurface hydrological processes. [Result] Our review reveals that the mechanisms underlying the influence of rock fragments on subsurface hydrological processes remain obscure, and current methods are unable to capture the complex causal relationship between rock fragments and soil hydrological processes. Areas such as quantification of rock fragment heterogeneity and its association with soil hydrological parameters, multi-scale modelling of soil hydrological processes are still in the infant stage and require further work. [Conclusion ] We propose that developing innovative technologies and methodologies, and improving understanding of the underlying mechanisms are particularly important in future research. Specifically, future research should focus on characterizing rock fragments in deep soil and their influence on hydrological process and formation of preferential flow, methods to link gravel content to hydrological information at different scales. Improving research in these areas will advance our in-depth understanding of the impact of rock fragments on soil hydrological processes, helping develop sustainable water resource management in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecological Science is the property of Ecological Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to analyze the effects of sowing date and film mulching on yield and quality of direct seeding winter rapeseed to provide a theoretical basis for suitable sowing and high-yielding cultivation of winter rapeseed in dryland in southwest China. [Method] A two-factor completely randomized block design was adopted to explore the effect of sowing date(20th September, 30th September, 10th October, 20th October, 30th October, 10th November, 20th November) and film mulching (film mulching and no film mulching) on field soil temperature, dry matter accumulation, agronomic characteristics, yield and quality of Chuanyou 36. [Result] Film mulching effectively increased the 0-20 cm soil temperature, dry matter accumulation, plant height, length of main inflorscence and effective pods, thereby increasing rapeseed yield by 3.61%-44.47%, which was more obvious with the delay of sowing date. However, the sowing date delayed longer, dry matter accumulation and agronomic traits of rapeseed decreased significantly. The regression equation showed that the rapeseed yield rose first and then declined with the delay of sowing date, which had a significant polynomial relationship with sowing date. The optimal sowing date for rapeseed was 10th October, which was 2.13%, 47.97%, 74.19% and 136.64% higher than 30th September, 30th October, 10th November and 20th November, respectively. In addition, the delay of sowing date effectively reduced the content of linolenic acid, erucic acid and glucosinolates in rapeseed, but also reduced the oil content, while film mulching effectively decreased the difference in rapeseed quality resulted from the delay of sowing date. [Conclusion] 30th September to 10th October was a suitable sowing date for high yield of direct seeding rapeseed in dry land in southwest China, and a proper delay of the sowing period in combination with film mulching technology was more conducive to achieving goals of high yield, efficiency and quality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 The present paper aimed to carry out research on dynamic change characteristics of paddy field and dry land resources in Chongqing, identify the main factors driving the loss of paddy field and dry land resources, analyze the regional differences in the utilization of cultivated land resources, and provide support for improving the utilization rate of cultivated land resources, strengthening the management of provincial agricultural resources, and ensuring regional food security. 【Method】 Based on the interpretation results of historical remote sensing image data, the dynamic change characteristics and spatial differentiation of paddy field and dry land in the two historical stages of Chongqing from 1980 to 2000 and from 2000 to 2018 were quantitatively studied by using geographic gravity center analysis, cultivated land loss rate and other indicators and methods. 【Result】 The study found that areas of paddy field and dry land in each district of Chongqing decreased in the past 40 years. The loss area of paddy field was less than dry land, but the loss rate of paddy field was higher than dry land. The loss of paddy field and dry land both showed a trend from slow scattered occupation to rapid agglomeration occupation over time, and the area gravity center of both cultivated lands had gradually shifted to the northeast, indicating the shift from the western low-altitude area（with high economic growth rate and high-quality cultivated land） to the northeast hilly area（with relatively low economic growth rate and low quality cultivated land）. From 1980 to 2000, the area gravity center shift distances of paddy field and dry land were 0.58,0.97 kilometers, respectively, while that distances from 2000 to 2018 were 2.14,1.57 kilormeters. According to the result of cultivated land loss rate index, paddy field and dry land in most districts belonged to the slow loss type, and the losing rate from 2000 to 2018 was much higher than that from 1980 to 2000. Severely loss regions of paddy field were mainly located in the urban area and suburban areas. The regions of rapid loss were mainly concentrated in the northeast of Chongqing, and the severe and fast loss areas of dry land are concentrated in the urban area. Construction occupation was the primary factor of paddy field loss, and the ecological occupation was the secondary factor. Considering the loss rate of cultivated land resources and the types of cultivated land transformation, the dynamic types of cultivated land resources in paddy field and dry land could be divided into 4 categories, which were construction occupation dominated, ecological occupation dominated, no dominant type, and cultivated land type transformation. Furthermore, 10 subcategories can be identified based on their loss speed. 【Conclusion】There are regional differences in the main characteristics and driving forces of the loss of paddy field and dry land in Chongqing. It is necessary to strengthen the zoning management of paddy field and dry land based on the characteristics of regional cultivated land loss, optimize the ecological and landscape functions of existing cultivated land in the development zone, improve the resource utilization rate and comprehensive production capacity of cultivated land, and ensure food security. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] In order to comprehensively maintain and improve the production, ecological and living functions of the farmland ecosystem, under the different types of cultivated land, the present paper analyzed the spatial and temporal evolution trajectory and characteristic differences of the quantity and quality of the water and dry land in the cultivated land based on the perspective of the ’trinity’ protection for quantitative and quality ecological development.[Method] Taking the Jiangjin District of the Three Gorges Reservoir as an example, the land use status and cultivated land quality grade evaluation result data, the standard deviation ellipse, landscape pattern index, nearest neighbor index method, etc. were used to study the quantity, the spatial and temporal evolution pattern of quality and ecology. [Result]（i） Quantity, the distribution of flooded and dry land in Jiangjin District had a trend of further expanding to the hinterland of Jiangjin District. The evolution path of dry land changes from northwest to southeast, and the evolution path of paddy field changed from southwest to southeast;（ii） Quality, the overall quality of the paddy field was higher than that of the dry land. The grade of the paddy and dry land was gradually decreasing from the central and western regions to the north and south.（iii） Ecological, the shape of the paddy and dry land was complex and fragmented, with reduced connectivity and significant aggregation.[Conclusion] The implementation of arable land zoning and types of protection measures, to achieve the development momentum of characteristic agriculture according to local conditions, provides reference for the protection of arable land resources in this area, the formulation of ’tri-in-one’ protection policies and the optimization of the layout of arable land. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The objective of the paper is to provide the scientific basis for rational fertilization in Jianhe County of Guizhou Province and similar areas. [Method] The effects of soil nutrient indexes(total N .organic matter, available N .available K, available P, total P and total K)on soil fertility are explored by using variation coefficient method, correlation coefficient method and weighted mean method, and then the soil fertility in paddy field and dry' land is evaluated by using improved Nemerow comprehensive evaluation method combined with the weight coefficient mean value of the three methods. [Result] The soil available k in paddy field and total P in dry land were at a lower level, while other nutrient indexes were at a medium-high, high and higher level. The soil available N content in six dry' land sampling sites with different plants was high. Soil total P and available k fluctuate greatly among sampling sites, while organic matter content fluctuates less. The soil available P in fertility factor weighted coefficient of paddy field and dry land was the highest, respectively 0. 2710 and 0. 2358 comparing the mean value of the three weighted method weighted coefficient. The available P is the main factor influencing soil fertility in paddy field and dry' land and soil fertility indexes is 1.52 and 1.63 separately. The soil comprehensive fertility was at a fertile level. [Conclusion] The soil fertility of paddy field and dry land in Jianhe County is at a fertile level, and available P is the main factor influencing soil fertility in paddy field and dry land. The soil N content in paddy field and dry land is high, which can meet the demand of crop production. Therefore, N fertilization should be reduced in production. The soil K content in paddy field is low, and the corresponding fertilization measures should be taken to improve K supply level in paddy field. [ABSTRACT FROM AUTHOR]

【Objective】The objective of the paper is to provide a reference for soil nutrient management and sustainable operation in Karst areas.【Method】The soil samples were collected from woodland and dry land in Baiduo Village(dolomite areas) and Shiqiao Village(limestone areas) in Shibing County,Guizhou Province,and then the soil nutrient was analyzed.【Result】The soil developed from dolomite was featured with higher organic matters,total N,available P,available K and hydrolysable N.The soil developed from limestone was featured with higher total P and total K.Total N was positively and very significantly related to hydrolysable N and organic carbon in soil developed from limestone and dolomite.Hydrolysable N was positively and significantly related to organic carbon in limestone areas.Hydrolysable N was positively and very significantly related to organic carbon in dolomite areas.Land use patterns had obvious effects on nutrient content in soil developed from limestone and dolomite.Soil total K,total N,hydrolysable N and organic carbon content in limestone woodland was higher than dry land,and available K,total P,available P and pH was lower than dry land.Soil total P and available P in dolomite woodland are lower than dry land,and other indexes are higher than dry land.The organic matter,total N,total P and total K content in dolomite-developed soil was Grade II,Grade I,Grade VI and Grade III respectively.The organic matter,total N,total P and total K content in limestone-developed soil was Grade II,Grade I,Grade V and Grade I separately.【Conclusion】Soil nutrient was not only affected by soil forming rock,but also affected by land use pattern. [ABSTRACT FROM AUTHOR]

In this paper, the geochemical signatures were employed to investigate factor controlling on groundwater geochemical evolution in the Shule River basin in northwestern China, where groundwater extensive extraction occurs for agriculture and domestic supply. The results show that the TDS concentrations of groundwater gradually increases from the Qilian Mountains front to the Guazhou basin. Springs in the mountain front of the Qilian Mountains, the Yumen-Tashi groundwater, and the Guazhou groundwater were Ca-HCO3, Ca-Mg-HCO3-SO4 and Na-Mg-SO4-Cl types, respectively. Geochemical evolution in groundwater was possibly due to a combination of mineral dissolution, mixing processes and evapotranspiration along groundwater flow paths，but the mineral dissolution was the main cause. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coal mining in Jurassic coalfields of the arid Northwest area has damaged the local water resources greatly. Basing on the analysis of diachronic changes of the drainage and water balance of Jinjie Coal Mine, the paper gave some explanations of the changes of circulation patterns of groundwater before and after the mining. According to the changing characteristics of the water levels of pore water, fissure water and mixed water of double aquifers before and after mining, it was believed that the variation of the hydraulic properties of the roof aquifer in the mining area is mainly induced by the unified evolution of the transmission and closing property of roof aquifuge during the promoting process of mining face. The variation of the transmission and closing property of roof aquifuge changes the circulation pathways of mine groundwater, and the heavy-water deposits could be formed in the arid area. Also, the paper holds that the prediction method of real-time mine inflow based on variations of roof hydraulic properties will be one of the key issues in the future studies of deposit hydrogeology. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)