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In order to analyze the ecological management effect and future vegetation restoration potential of Ejina Oasis at the tail of the Heihe River, Normalized Difference Vegetation Index (NDVI) was extracted based on the MOD13Q1 data set from 2000 to 2020. This paper used Sen trend and M-K test to analyze the spatiotemporal variation characteristics of vegetation in the Ejina Oasis. Considering the factors of topography, geomorphology, hydrology, soil and vegetation type, the similar habitat method was used to explore the potential and spatial pat- tern of oasis vegetation restoration. The results show that NDVI shows an increasing trend from 2000 to 2020, and the annual growth rate is 0.001 3/a. The proportion of areas with a significant increase in NDVI in spring on a seasonal scale is the highest. The vegetation coverage near the Ejina Banner government is relatively high and the vegetation coverage in the middle reaches of Xihe River increases significantly during the study period. In the future, the vegetation will still show a spatial distribution pattern of high around the two rivers and low at the edge of Ejina Oasis. The lower reaches of the surrounding areas of the tail lake are close to or have reached the maximum recovery potential. The vegetation enhancement potential of Badaohe to Swan Lake channel, Qidaohe tail channel, Sidaohe and Liudaohe tail channel and the west of Xihe lower section are great. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River 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 Yellow River is the property of Editorial Board of Yellow River 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 Yellow River is the property of Editorial Board of Yellow River 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 clarify the health status of the East Juyan Lake wetland ecosystem, the press-state-response model was used to construct the evaluation index system of the ecosystem health of the East Juyan Lake wetland. This index system included three primary indicators, namely pressure, state and response, and 13 secondary indicators. Further, Pearson bivariate analysis in SPSS software was used to test the correlation between each sub-index and the system index. The results show that natural pressure of East Juyan Lake wetland ecosystem is decreasing and social and economic pressure (artificial pressure) is increasing; overall response of plants and animals in the wetland is gradually developed in a positive direction；interdecadal health status of wetlands is healthy - subhealthy - morbid - subhealthy - healthy - very healthy; the health of East Juyan Lake wetland ecosystem is most closely related to the amount of lake water and animal species, and the main external pressure comes from fishery and tourism. [ABSTRACT FROM AUTHOR]

The evaporation and leakage of continental river channel seriously affect the efficiency of water transportation and management of water resources in arid region. In order to realize the optimal allocation of the Heihe River ecological water transfer, it is necessary to quantify the amount of river loss accurately. In this article, the relationship between discharge and the surface area of river was established based on the observed hydrological data and the area interpreted by remote sensing. With the relationship and meteorological data, the evaporation and leakage of LangxinshanZhengyixia section were calculated respectively by water balance method. The results show that the channel leakage is the mainly water loss in the lower reaches of the Heihe River. The annual leakage of ZhengyixiaLangxinshan section is about 277 million m3 and the evaporation is about half of the leakage. For different reaches, the evaporation and leakage of ZhengyixiaShaomaying section are about 3-5 times of the ShaomayingLangxinshan section respectively, while the trends of the two sections are basically the same. [ABSTRACT FROM AUTHOR]

According to the need of unified regulation of Heihe River's water quantity, this paper quantitatively studied the factors affecting the loss rate of evaporation and seepage in the lower reaches of Heihe River after unified regulation by using statistical methods. The relationship between the loss rate of evaporation and seepage in the river course and the discharge amount under the upper section and the time of water diversion (closing time) was also analyzed. The results show that the loss rate of evaporation and seepage in the river course is closely related to the discharge amount under the upper section and the time of water diversion. The larger the discharge amount under the upper section, the smaller the loss rate of evaporation and seepage. The longer the time of water diversion, the smaller the loss rate of evaporation and seepage. According to the established empirical formula, when the discharge amount under the upper section is larger and the time of water diversion is shorter, the loss rate of evaporation and seepage is smaller; otherwise, it will be larger. [ABSTRACT FROM AUTHOR]

近年来，黄河北干流河段河道整治、水资源利用、滩涂开发和工业与民用建筑等方面的建设项目越来越多，与河争水、与河 争地现象日益严重，引发的水事矛盾愈显突出。 但是，目前黄河北干流河道管理缺乏法规的支持，流域机构同地方政府之间，地方 政府各部门之间的职责和权限不明确，有关法规缺乏可操作性。 因此，建议通过立法调整和规范黄河北干流河道治理、开发、管理 和生态保护工作中各方面的关系，针对黄河流域生态保护和高质量发展协调各省（区）推动配套法规的立法工作尽快进行。 [ABSTRACT FROM AUTHOR]

An environmental protection type long-bag filling machine was developed through overall function design, theoretical calculation and equipment selection, main technical parameters selection and validation of productive test, aiming at the problems of consuming more manpower, low efficiency, high cost, high labor intensity and bad safety in the traditional emergency treatment methods such as bundling and throwing willow stone pillows in the Yellow River flood control and emergency rescue. Experiments show that the machine has high filling efficiency, convenient operation, flexible movement and convenient maintenance, with two sets of independent filling system can realize two long-pipe bags simultaneously rapid filling and positioning throwing, and meets the field operation conditions and suitable for natural flood control materials. The practical application shows that the equipment can win time with higher filling and throwing speed and efficiency of long-pipe bags for flood control and rescue and has remarkable social, economic and environmental benefits. [ABSTRACT FROM AUTHOR]

Copyright of Yellow River is the property of Editorial Board of Yellow River 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 ensure the smooth construction of a large directional drilling pipe through Qin River, the construction unit carefully studied technical difficulties, made rational selection and kept rigid control of the maximum mud pressure, the speed of reaming, the viscosity and the gravity of mud and other key technical parameters, formulated the construction measures against the oozing slurry and took pre-reinforcing in the weak ground of the traversing route. It strictly controlled the guide hole construction trajectory, accuracy of entry angle and unearthed angle. In the course of drilling, mud pressure, drilling speed and other control parameters were corrected at any time when the mud pressure, drilling trajectory and mud circulation reflected the difference between the actual geological conditions and the design, achieved the goal of smooth drilling, no oozing slurry in the whole process and precise pipe location, as well as creating a number of domestic construction records by using directional drilling with double pipes across channel projects, such as the diameter of the pipeline diameter 1, 016 mm, the crossing length of 1,750 m and the maximum buried depth of more than 33 m. [ABSTRACT FROM AUTHOR]

In order to analyze Heihe River middle reaches area of the ecological environment change trend and its formation mechanism，this paper selected the 2000 and 2011 study area remote sensing image data to establish the land use type matrix for remote sensing image data analysis. The results show that:a） in 2000-2011，in the middle reaches of Heihe River，the mainly evolution trend of the ecological environment is from the unused land to cultivated land，other types of land use conversion is also frequently; b) the main factors which the trend of the ecological environment are the results of the interaction between the natural factors and human factors, among them, human factor occupies the mainly position. [ABSTRACT FROM AUTHOR]