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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 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 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.)

Most pastoral areas in China are subjected to arid and semi-arid zones, particularly with annual precipitation of less than 400 mm. Since irrigation is indispensable for the cultivated grass industry, the protection of natural grassland can focus on the water, land, forage, and livestock balance with the development of the irrigation cultivated grasslands, rather than the forage-livestock balance only. Taking the specific pastoral management units as the entry point, this study aims to propose a new evaluation for the tradeoff between the water and land for the family pasture from the perspective of the water cycle. A water-land-forage-livestock balance was constructed to consider the quality differences between forage species in the calculation of the forage-livestock balance. An example was taken as the typical family pasture in the Otog Front Banner of the Inner Mongolia Autonomous Region in China. The assessment showed that the current water, land, forage, and livestock status of the family pasture were in a mild overload state, with a water resource overload rate of 6.05%. In the condition of water, land, forage, and livestock balance, the livestock overload rates with/without considering forage quality were 5.38% and 12.98%, respectively. By contrast, the livestock overload rates with/without considering forage quality were 1.29%, and 9.05%, respectively, under current planting conditions (without considering water resource overload). An optimal combination of water-use schemes was proposed to feature the different planting structures and irrigation adjustments, according to the status quo in this family pasture. A systematic analysis was made to determine the available water supply, and the carrying capacity for the irrigation of cultivated grasslands, and livestock under multiple optimizations. It was found that the carrying capacity was determined for the irrigation of cultivated grasslands by the available water supply. More water-efficient irrigation was adopted to select the forage crops with the decreased water consumption, in order to significantly improve the support capacity of water resources in the irrigation-cultivated grasslands. Livestock carrying capacity significantly increased after considering the forage quality, indicating more consistency with the actual condition of this family pasture. Consequently, the family pasture was maintained the current areas of cultivated grassland without increasing, while adjusting the irrigation of alfalfa to underground drip irrigation. Once the irrigation form was adjusted to drip irrigation under the condition of oat planting, the number of livestock was reduced to 464 sheep units, in order to maintain the balance of water, land, forage, and livestock in the family pasture. Furthermore, the oats were adjusted to grow the corn or alfalfa in the median condition of oats. Although the number of livestock was more than the current number of livestock, some suggestions can keep the current number of livestock raised in family pastures, in order to make more room for the rest and recuperation of water resources and natural grassland. The finding can provide a new approach to calculating and managing the water, land, forage, and livestock balance in pastoral areas. [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 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 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.)

The black soil region of Northeast China is one of the most important grain production bases in China. It is also one of the four major water erosion areas in China, in which the erosion gully is the main form of water erosion. In order to analyze the causes of gully erosion and evaluate the basic situation of gully erosion in the northeast black soil area, it is necessary to analyze its morphology and distribution characteristic of gully erosion. In this paper, Nenjiang County was taken as the study area, which is located in the northwest of Heilong province, China. The aerial remote sensing images with ground resolution of 0.2 m and 1:50 000 Digital Elevation Model (DEM) were used to carry out census and statistics on the erosion gully, and the morphological characteristics such as the gully width, gully length and longitudinal slope of the erosion gully were analyzed, as well as the influence of terrain factors such as elevation, slope and aspects. The results of the second land use survey in China were used to obtain the land use situation around the erosion ditch. The results showed that: 1) The number of erosion gullies in Nenjiang County was 38 426, and the whole area of the erosion gullies were 16 277 095 m2. The erosion gully mainly occurred on hilly area, and was dominated by gully erosion, accounting for 74.50% and 51.05% of the total number and area, respectively. The next type was modern incised valley. Erosion gullies were mostly less than 500 m. 2) The width and length of the erosion gullies were positively correlated, and the slope was negatively correlated with the width and length. 3) Compared with slope, aspects generally had a little effect on the distribution of erosion gullies. Rills and ephemeral gullies mainly distributed on slopes of 2~6° and 6~15°, and gullies and modern incised valleys mainly distributed on slopes of 0~2° and 2~6°. More than 90% of rills and ephemeral gullies, and 80% of gullies and modern incised valleys were occurred on cultivated land. 4) Although the topographic threshold model of gulley in Nenjiang County was not fitted well, it could still be used to analyze the process of gully erosion. The model showed that the critical slope of the modern incised valley was small, the parameter which expressed the gully erosion process reflected the occurrence and development of the gullies might be influenced by the underground process. [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.)

The dynamic change of water level in a hydrological year can keep riverbank soil in the state of alternating dry and wet. The variety of water content of riverbank soil can change the mechanical properties of soil to a certain extent, which can affect riverbank stability. In order to investigate quantitatively the influence of dry-wet alternation condition on mechanical properties of riverbank clay soil, a field observation and sampling were first conducted at eight typical riverbanks in upper and lower Jingjiang Reach, which the clay soil of the typical riverbanks in Jingjiang Reach of the Yangtze River was taken as the study object. Through a comprehensive analysis of measured data, indoor soil tests and BSTEM simulation, the composition and mechanical properties of these samples were obtained, which indicated that the vertical soil composition of riverbank was characterized by a typical composite structure of non-cohesive lower bank and cohesive upper bank. The indoor soil test results revealed the quantitative change of soil mechanics with dry-wet alternation condition, and a close relationship between water content and shear strength indicators was obtained. With an increase of water content, the cohesion first increased and then decreased, with the peak values of 21 kPa and 34 kPa for the critical water content of 16.0% and 22.8% at Jing 61 and Beimenkou sections, and eventually reached a constant, while internal friction angel decreased significantly. Considering the dry-wet alternation condition of riverbank soil and the change of river water level in a hydrological year, the degrees of riverbank stability at Jing 61 and Beimenkou sections were analyzed during four different water level periods using BSTEM, and the process of bank failure of two sections were simulated in 2013. The results indicated that: the model-predicted results of the total bank retreat width were in close agreement with the measured data with the relative errors 1.69% and 3.74%, respectively. At the same time, the safety factors under different dry and wet conditions were calculated based on the BSTEM simulated results of two typical sections. The relationship between safety factor and water content was obtained, which indicated the safety factor first increased and then decreased with an increase of water content. It was consistent with the relationship between soil cohesive and water content which proved that the soil cohesive has an important influence on the stability of river bank. Quantitative relationships between safety factors and cohesive and internal friction angle of two typical sections were identified, respectively, and the correlation coefficients were 0.980 and 0.876 for Jing 61 section, and 0.992 and 0.986 for Beimenkou section, respectively. The relationships between them were linear function from which the safety factors increased with the increase of the cohesive and internal friction angle, respectively. Thus, a conclusion can be drawn that the safety factor was mainly affected by soil cohesive under different dry and wet conditions. For actual project, when water content of the riverbank soil was obtained, the cohesive and internal friction angle of soil can be calculated by proposed formulas, thereby the safety factor of riverbank can be calculated and the stability of river bank can be identified. [ABSTRACT FROM AUTHOR]

Agricultural land consolidation is one of the largest human activities in China with lots of impacts on ecological environment. Ecosystem services are the basis for human survival and development. It is of great significance to explore the impacts of agricultural land consolidation on regional ecosystem services. This study would promote the balance, efficiency and stability of the ecosystem services in the agricultural land consolidation area. This research took Jianxi River Basin which in Fujian province as case study area. The data used in this paper were remote sensing data, the agricultural land consolidation project data, land use data, soil type map and so on. Carbon storage ecosystem services in the Jianxi River Basin were estimated by using the multi-source model of carbon storage. And crop production ecosystem services in the Jianxi River Basin were estimated by using the potential productivity model of cultivated land. Based on the comparative analysis, the effects of agricultural land consolidation on two ecosystem services were studied. The research showed that compared with 2010, total carbon storage decreased by 38.28×106t in 2016. The total carbon storage in 2016 was 369.29×106 t. The area of agricultural land consolidation project accounted for 1.41% of the area of the Jianxi River Basin. And the project area contributed 1.70% to the decrease in carbon storage. This indicated that agricultural land consolidation has negative effects on carbon storage services in the ecosystem of Jianxi River Basin. The carbon effect produced by agricultural land consolidation should not be neglected. Compared with 2010, the total crop production service in Jianxi River Basin increased by 10.83×104t in 2016, reached to 124.46 ×104t. The area of agricultural land consolidation project accounted for 14.61% of cultivated land area of the Jianxi River Basin. And the project area contributed 20.87% to the increase in crop output. This indicated that agricultural land consolidation has effectively improved the crop production services of cultivated land in the Jianxi River Basin. It is necessary to pay attention to the application of ecological measures in agricultural land consolidation. According to the research results that carbon storage services will be reduced by agricultural land consolidation, and three suggestions are put forward. 1) If the agricultural land consolidation measures would do great damage to the cultivated soil, measures such as topsoil stripping and backfill and guest soil should be adopted to protect the carbon sequestration capacity of the soil. Planting green manure and returning straw to field is also an effective biological measure to increase soil carbon sequestration. 2) Attention should be paid to the construction of ecotype ditches and field roads, and new environment friendly materials such as environment friendly field sand stone pavement additive, soft slope protection material, heavy metal passivating agent, water retaining and fertilizer agent and so on are used to reduce the loss of organic carbon storage caused by pavement hardening and excessive coagulation. 3) Strengthen the management and protection of agricultural land consolidation. Intercropping rotation system and farm manure should be used to increase the carbon storage of cultivated land through later management and protection. [ABSTRACT FROM AUTHOR]

The thermal insulation performance of granary envelope has important impacts on grain storage safety and granary energy consumption. The roof of a granary is usually very large. Because roof is the position with the strongest solar radiation in granary, the external heat is mainly transferred into granary through roof. Therefore, granary roof is the key part in the design of thermal insulation in building envelope of granary. Double-skin ventilation roof, high reflectivity coatings for roof, and thermal insulation material are three popular techniques for roof of granary for stored grain safety and more energy saving. According to different solar radiation levels and different climatic characteristics, the optimum thermal insulation thicknesses of roofs is different in different areas of China. In this paper, the transient heat transfer model of multi-layer roof was presented and validated for calculating energy consumption of ordinary roof in low temperature granary. By considering the influence of natural ventilation, a heat transfer model of double-skin ventilation roof was proposed and validated for determining energy consumption of double-skin ventilation roof. In this pater, the P1-P2 economic models were used to study the optimum thermal insulation thicknesses of the ordinary multi-layer roof and the double-skin ventilation roof of the low temperature granaries in Changsha region. The effect of different solar radiation reflectivity rates of outside surface was considered in determining the optimum thermal insulation thickness of the low temperature granary roof in Changsha region. The optimum thermal insulation thicknesses of two thermal insulation materials including expanded polystyrene and expanded polystyrene were calculated for ordinary roof and double-skin ventilation roof of the low temperature granary in Changsha region by using P1-P2 economic model respectively. And then, on the basis of life cycle cost analysis, the total life cycle costs, life cycle savings and payback periods were calculated. The results of this research showed that the solar radiation reflectivity of outside surface has a significant impact on the economy and the optimum thermal insulation thickness of the low temperature granary roof in Changsha region. Double-skin ventilation roof can reduce the optimum thermal insulation thickness of low temperature granary roof. Double-skin ventilation roof and high reflectivity coatings for roof should be adopted in roof of low temperature granary in Changsha region for more energy saving and less environmental pollution. The optimum thermal insulation thicknesses range of extruded polystyrene and expanded polystyrene was between 0.106-0.183 m for ordinary roof of low temperature granary. The maximum life cycle savings range from 417 to 633.38 RMB Yuan/m2. The payback period ranges from 2.39 to 2.96 years for the optimum thermal insulation thickness of roof. Expanded polystyrene has thicker optimum thermal insulation layer than extruded polystyrene. Expanded polystyrene has shorter payback period of optimum thermal insulation thickness of roof than extruded polystyrene. The optimum thermal insulation thickness of the roof decreases with the increase of the solar radiation reflectivity of outside surface of the roof. The double-skin ventilation roof can shorten the payback period of the optimum thermal insulation thickness of the low temperature granary roof. Besides, this determination method of optimum thermal insulation thickness of roof has a certain guiding significance for guiding design process of thermal insulation thickness of low temperature granary roof. [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.)

In order to improve the automatic extraction of cultivated land in irrigation area in remote sensing images, according to the planting structure characteristics in Shenwu irrigation area, Hetao Irrigation District, the NDVI (normalized difference vegetation index) time series of main crops in the study area were constructed based on field survey results, Google earth and GF1-WFV remote sensing images. OIF index was used to select the best band combination. Furthermore, the harmonic analysis of time series (HANTS: An improved algorithm based on Fourier transform, which can flexibly deal with the problem of unequal intervals of data that constitute the time series) method was employed to smooth the NDVI time series. Visual interpretation based on remote sensing and Google earth, supervised classification (support vector machine), and the combination method of supervised classification and decision tree classification based on NDVI time series (before and after smoothed by HANTS filtering method) were used to extract the cultivated land area of the irrigation area. The extraction errors of different methods were verified by visual interpretation and 100 000 000 random verification points whose attributes were given by the means of Google earth and visual interpretation. Moreover, 3 indices, i.e. accuracy (equivalent to the user precision in the confusion matrix), integrity rate (equivalent to the producer accuracy in the confusion matrix) and overall accuracy (ratio of extracted land area to actual area) were used to evaluate the results. The results demonstrated that the accuracy, integrity rate and overall accuracy of supervised classification (support vector machine) were only 84.82%, 64.4% and 75.68%, respectively; for the combination method of supervised classification with decision tree classification based on NDVI time series (unsmoothed), the 3 indices were 94.28%, 84.21% and 89.1%, respectively; the combination method of supervised classification with decision tree classification based on NDVI time series (smoothed) was further improved, and the 3 indices reached 94.47%, 87.32% and 92.24%, respectively. The GF1-WFV data can be used for extraction of cultivated land area, which has better spatial and temporal resolution, and has stronger ground identification ability in the irrigation area with more complex underlying surface. The NDVI time series based on the GF1-WFV data can describe the crop growth law in the study area completely, and can be used to extract the crop spatial information accurately and efficiently through the difference in the amplitude and the phase of the NDVI curve between different crops. It avoids the phenomenon of pixel-based traditional classification, for example, different objects have the same spectrum and the same objects have different spectrum, and overcomes the limitations of single image data. Compared to the results of supervised classification, the accuracy is greatly improved. After smoothing by HANTS method, the NDVI time series keep the basic shape of the original curve, and effectively eliminate the influence of outliers and noise, which more tally with the actual growth law of crops. Through the combination of supervised classification with decision tree classification based on NDVI time series (smoothed), the extraction precision of cultivated land is improved effectively. The method combining crop growth law and remote sensing information can improve the extraction accuracy of cultivated land area effectively. [ABSTRACT FROM AUTHOR]

Single-layer cylindrical reticulated shell structures with the advantages in providing powerful transfer loads capability, large span space, excellent economic index, good light transmission performance and beautiful architectural style, not only are widely used in civil engineering, but also get more and more use in greenhouse construction because they can meet the requirement of rapid development of facility agriculture. Considering the high frequency of disaster winds in many regions of China, and the characteristics of reticulated shell structure including low overall stiffness, numerous vibration modes and great sensitivity to wind loads, the dynamic collapse may occur for single-layer reticulated cylindrical shell structure with large span and light weight in the weather of severe disaster winds. To analyze the collapse mechanism and the influence factor of this type of structure under wind loads is very important for the engineering design and theoretical analysis. In this paper, the analysis model of global dynamic collapse for single-layer cylindrical reticulated shell structure of greenhouse under wind loads was established by considering geometric nonlinearity, material nonlinearity and contact nonlinearity. In the numerical analysis, the effective plastic strain was defined to simulate the failure of tension members. To illustrate the influence of dynamic buckling of compression members on the collapse of the structure, each member was equally divided into 6 beam elements. The finite element explicit analysis software ANSYS/LS-DYNA was employed, and the dynamic buckling of compression members was considered. The collapse process of reticulated shell was analyzed and then was showed with the maximum nodal displacement, the deformed configuration and the plastic member distribution of the structure at different time. Based on the numerical analysis results and performance of the structure, the collapse process of reticulated shell was divided into 3 stages, which were named mild damage stage, collapse formation stage and overall collapse stage respectively. During the first stage (from the beginning to 21.7 s), the reticulated shell was generally in a deformation recoverable state with only a few members entering the plastic state in the compression area of the center and both ends of the structure. Therefore no local collapse occurred and little damage was produced to the structure performance. In the second stage (from 21.7 to 22.6 s), a series of dynamic buckling of members in the wind pressure zone from the bottom to the top of shell occurred, and a band-like buckling region was formed. At the same time, a number of tensile members entered the plastic state and gradually formed a plastic area. This weakened the stiffness of the structure, caused the structural vibration equilibrium position to deviate from its initial position, and finally caused the local collapse in the compression area of the structure. In the third stage (after 22.6 s), the plastic deformation of members in the buckling area of the reticulated shell reached its failure strain at first, and then the fracture failure of the members occurred. Under continuous dynamic forces, the collapse area rapidly expanded with the time, and finally led the shell to lose structural integrity completely at 24.8 s. In addition, considering most of the reticulated shell structures were supported with substructure, this paper also investigated the influence of substructure on the dynamic collapse performance of the upper reticulated shell under wind loads. The same reticulated shell model used above but without substructure was analyzed. The results of calculation showed that the load factor of the collapse of reticulated shell with substructure was reduced by 25% compared with that of the reticulated shell without substructure. The substructure would weaken the stiffness of the whole structure, and therefore reduce the wind loads bearing capacity of reticulated shell structure. It was necessary to consider the influence of substructure in the dynamic collapse analysis of reticulated shell structure under wind loads. Otherwise, the wind loads of the collapse of reticulated shell would be over-estimated. Based on the analysis results, some conclusions are drawn, which provide the basis theoretical reference for engineering analysis and further studies of reticulated shell structure in modern greenhouse. [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.)

At present, China is in the period of economic and social transformation and the initial stage of ecological civilization construction. The career of China’s land consolidation is in unprecedented strategic opportunity period. Now the development of land consolidation is facing a totally new situation, new opportunities, but also many serious challenges. Ecological transformation of land consolidation is the inevitable requirement of the development of the national strategy, but also the trend of the development of land consolidation. Proportion of ecological research literature on land consolidation in research literature on land consolidation is getting higher and higher. Ecological land consolidation research has become an important part of land consolidation research. Based on the study of ecological transformation background of Chinese land consolidation, this paper analyzed the existing ecological problems of land consolidation, discussed the connotation of ecological land consolidation, and proposed "Four strategic orientations" for ecological transformation of land consolidation to safeguard the food security and realize the environmental protection function of land consolidation. There are some ecological problems in the current land consolidation work. First, theory method and technology system of ecological land consolidation are not perfect. Compared with developed countries, China’s ecological land consolidation technology system seriously lags behind the practical application, and it has not yet formed a systematic scientific theoretical method and technical system for ecological land consolidation. Second, land consolidation is lack of attention to rural culture. Some places in the land consolidation simply pursue quantity of cultivated land and modern architectural styles, and ignore the protection of rural culture. Third, ecological land consolidation is lack of new ecological material and new technology, which is difficult to meet the needs of the development of ecological land consolidation. This paper stated that in the era of ecological civilization construction, land consolidation is no longer a simple planning and construction of land use. Ecological land consolidation should combine land consolidation with traditional culture and regional development, improve its implementation path, public participation and development model, and reduce ecological pressure and its negative impact. The ecological environment effects should be considered in the process of land consolidation. And protecting the ecological environment should be the main target of land consolidation. The goals of intensive production, enhancing quality of life, and improving ecological environment should be realized through the "quantity control, quality management, ecological protection and management". According to the ecological environment problems in land consolidation, this paper proposed "Four strategic orientations", which are 1) promoting the awareness of the ecological effect of land consolidation; 2) improving the study of theory and technology system of ecological land consolidation; 3) accelerating the development of new ecological material and new technology of land consolidation work; 4) strengthening public participation, and paying attention to the protection of rural landscape and the application of local techniques. With these 4 strategy orientations, land consolidation can be regarded as the powerful supporter and important platform to maintain food security and protect the environment in an all-round way. Of course, the legal system is also needed to promote the transformation of ecological land consolidation. Improving land consolidation planning system, and strengthening education are also the important guarantee of ecological transformation of land consolidation. [ABSTRACT FROM AUTHOR]

Solar greenhouse is an important agricultural facility in northern China. It is suitable for production in early spring, late autumn and winter cultivation, but difficult in summer. For northern Jiangsu Province, the air temperature is higher in winter and the high-temperature period is longer than North China, Northeast China and Northwest China. To improve usage efficiency of solar greenhouses in northern Jiangsu Province, the structure of solar greenhouses needs to be modified to improve the insulation in winter and ventilation cooling performance in summer. To achieve this purpose, a novel solar greenhouse with removable north wall (experiment greenhouse) was designed in this study, in which part of the north wall can be dismantabled when necessary while the rest of the wall is fixed. The performance of an experiment greenhouse was compared with a traditional solar greenhouse with north wall of hollow blocks (control greenhouse). Air temperature and relative humidity in the 2 greenhouses were firstly mearsured from July 15 to August 14, 2014 and from December 11, 2014 to January 10, 2015. Secondly, wall thermal parameters (thermal resistance, heat transfer coefficient, heat storage coefficient, thermal inertia index, attenuation coefficient), wall temperature and heat flow density of the 2 solar greenhouses were compared to reveal the insulation performance differences between them. The ventilation cooling performance of 2 greenhouses was compared in term of indoor air flow. Thirdly, indoor crop growth, yield per plant and input-output ratio of 2 solar greenhouses were compared. The calculation showed that the heat storage coefficient, thermal inertia index and attenuation coefficient toward the outside temperature fluctuation of the fixed wall of the experiment greenhouse were 3.9, 10.8 and 18.3 times that of the control greenhouse respectively. The heat storage coefficient of the straw wall of the experiment greenhouse was lower than the traditional hollow block wall, but the thermal inertia index and attenuation coefficient of the former were 3.7 and 1.7 times that of the later. This suggested that the straw could be used as the insulation material of north wall. The experiment results showed that the temperature of the fixed wall in the experiment greenhouse rose more slowly than the control greenhouse in the morning, and decreased more slowly in the afternoon while the temperature was higher during nighttime. But the temperature of the detachable wall exhibited the opposite trend. For the experiment greenhouse, the heat flow density at the inner surface of the fixed wall was about 18.3% greater than the control greenhouse during the nighttime, and the exothermic time was longer by about 2.1 h. The average air temperature in the experiment greenhouse was 1.1 and 1.0 °C higher than the control greenhouse, respectively, at daytime and nighttime and the average relative humidity was lower by 9.1% and 6.8%, respectively. The experiment greenhouse had better performance on insulation and humidity control than the control greenhouse in winter. With greater vent area of natural ventilation, the air flow rate inside the experiment greenhouse was obviously higher than the control greenhouse. The heat loss inside the experiment greenhouse was greater than the control greenhouse in summer. The average air temperature at daytime and nighttime in the experiment greenhouse was 4.0 and 3.1°C lower than the control greenhouse in summer respectively; the daily highest temperature was lower by 1.4-8.1 °C. The experiment greenhouse had better ventilation cooling performance than the control greenhouse in summer. For crop yield, the tomato yield per plant was 16.7% higher than the control greenhouse in winter. The yield of non-heading Chinese cabbage was 38.5% higher than the control greenhouse in summer. The input-output ratio of the experiment greenhouse was 1:5.64, which was 8.05% higher than the control greenhouse. Overall, the novel greenhouse operated well in both winter and summer. So, the novel greenhouse is a suitable type of greenhouse for year-around production in northern Jiangsu Province. [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 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.)

Xinjiang Uygur Autonomous Region is the largest cotton-production area of China. As a water saving and high yield irrigation technique, mulched drip irrigation is popular water application method for cotton production in Xinjiang Uygur Autonomous Region. Studying the response of cotton yield to irrigation amount is of great importance. In this study, a two-dimensional soil water transport and crop growth coupled model was calibrated and validated using field data of cotton under mulched drip irrigation, and then used to estimate the cotton yield under different irrigation amount. The field experiment was conducted at the experimental station located in Urumqi, Xinjiang Uygur Autonomous Region, China, during the cotton growing seasons of 2010 and 2011. In this experiment, 3 irrigation levels of 50%, 75% and 100% of full irrigation were adopted. For the full irrigation treatment, irrigation was applied when the averaged soil moisture within the root zone (40 cm for the squaring stage and 60 cm for the bloom stage) was depleted to 60% and 70% of the field capacity for the squaring and bloom stages, respectively. The irrigation was applied until the soil water content reached to 85 % and 95% of the field capacity for the squaring and bloom stage, respectively. Soil water content was measured weekly by a Trime-FM probe to 100 cm depth to determine irrigation schedule. Leaf area index and aboveground biomass of cotton plant were observed at squaring, bloom, and boll-forming stages. At the end of each growing season, the seed cotton was harvested by hand. Considering the features of water transport from emitters into soil, a process-based two-dimensional soil water transport and crop growth simulation tools would be preferred to modeling the response of crop yield to irrigation amount under mulched drip irrigation. The coupled model was coded in program subroutines and functions integrated with CHAIN_2D and the crop growth model of EPIC. This model was written in FORTRAN 90 for Windows system. In the coupled model, the root water uptake model of Vrugt was coupled with the root depth growth model in order to consider the interaction between root water uptake and crop growth. To study the response of cotton yield and water productivity to irrigation amount, the two-dimensional soil water transport and crop growth coupled model was calibrated and validated by soil water content dynamic, crop growth indexes and seed cotton yield obtained from the field experiments. The calibration and validation results indicated that the coupled model performed well in predicting the soil moisture, above ground biomass, seed cotton yield and total water use. The values of normalized root mean square error (nRMSE) and index of agreement between observed and simulated soil water contents was 4.6%-23.4%, and 0.677-0.974, respectively. The nRMSE values of leaf area index and aboveground biomass was 6.3%-15.7% and 7.2%-14.1%, respectively. The differences between simulated and measured seed cotton yields and water uses were ranged from 1.1% to 6.7% and from 0.3% to 9.2%, respectively. Furthermore, the calibrated two-dimensional soil water transport and crop growth coupled model was used to simulate seed cotton yield and water productivity under 10 irrigation scenarios, i.e. 40%-130% of full irrigation amount with the increment of 10%. The results showed that the seed cotton yield and water productivity were increased and decreased through quadratic functions as the irrigation amount increased, respectively. Therefore, this study suggested that the appropriate mulched drip irrigation amounts for cotton in the North Xinjiang region ranges from 280 to 307 mm considering the yield and water productivity. [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.)