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Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China 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 Geomatics & Information Science of Wuhan University is the property of Geomatics & Information Science of Wuhan University 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.)

Ecosystem provides necessary ecological service function through material cycle, energy flow and information transmission, and the change of the ecosystem structure can change the ecosystem process and service function. It is of great significance to study the response process of ecosystem service function to the change of ecosystem structure for the efficient allocation of environmental resources and the rational formulation of environmental policy. In this paper, the change of ecosystem structure and service function in Fuping Basin of the Daqinghe River in recent 30 years was studied by using remote sensing images. The results showed that: 1) The ecosystem structure in the study area changed obviously during 1985- 2015. Construction land, forest land, cultivated land and water area increased 139.57% , 90.66%, 68.79% and 6.55% respectively. Unused land and grassland decreased -83.48% and - 54.92%, respectively. The increase in forest land was mainly at the cost of grassland and unused land that 622.67 km2 of grassland and 431.45 km2 of unused land were turned into forest land, the transfer rates being 28.8% and 18.22% , respectively. The expansion of cultivated land was mainly at the cost of unused land and grassland that 1 063.50 km2 of unused land and 831.41 km2 of grassland were turned into cultivated land. Construction land was mostly transferred from cultivated land and unused land that 441.91 km2 of cultivated land and 259.51 km2 of unused land were turned into construction land. Over the 30 years, unused land mainly turned into cultivated land and forest land. 2) The value of ecosystem services in the study area in 1985, 1990, 1995, 2000, 2005, 2010, 2015 was 44.29×108, 44.62×108, 44.65×108, 58.08×108, 51.71×108, 53.22×108, 52.72×108 yuan respectively. The highest value was in 2000. Forest land contributed the largest amount of the ecosystem value in the study area, followed by cultivated land and grassland. As for the value of single ecosystem service, soil formation and protection had the largest contribution rate, followed by biodiversity maintenance, gas regulation and climate regulation. 3) The increase of service value in the study area was due to the conversion of the grassland to woodland and the unused land to woodland. The loss of the service value was due to the conversion of the cultivated land to the construction land and the loss of forest land into cultivated land. [ABSTRACT FROM AUTHOR]

Fraction vegetation cover (FVC) can be used to indicate the growing status of vegetation, which is an important input for some ecological models, hydrological models, meteorological models, and so on. And FVC data set with high precision, high temporal resolution, and high spatial resolution is critical to global change monitoring. Unfortunately, current FVC products are produced using only one kind of remote sensing image, and thus their spatial coverage and temporal coverage are limited. Aiming at acquiring continuous FVC data in space and time, we explored the estimation methods of FVC of winter wheat in North China Plain using high and medium resolution images jointly. This study focused on dimidiate pixel model by combining multi-source images including GF1-PMS images with spatial resolution of 8m, GF1-WFV with spatial resolution of 16m, and HJ1-CCD with spatial resolution of 30 m. Four phases of remote sensing images of those 3 sensors were selected as data source to conduct the experiments, which covered 4 growth periods of the winter wheat, including turning green &rising stage (March 23, 2015 and March 29, 2015) and jointing & flowering stage (April 28, 2014 and May 5, 2014). Within the coincidence regions of those 3 kinds of images, we selected randomly 160 winter wheat sample areas (240 m×240 m) as the regression samples, and chose randomly another 80 winter wheat sample areas (240 m×240 m) as the checking samples to verify the performance of the methods. Using these regression samples, we developed multi-source whole-growth-period method (MWM) and multi-source single-growth-period method (MSM) based on the bottom-up method. We compared and analyzed the single-source inversion method (SIM), MWM and MSM based on the estimated FVC result using high spatial resolution GF1-PMS images. The results indicated that the FVC estimations of HJ1-CCD, and GF1-WFV images using SIM method were highly consistent with those of GF1-PMS images, and their R2 values were both higher than 0.9. However, due to the observation angle effect of GF1-WFV and HJ1-CCD sensors, the estimated FVCs were a little higher in the early growing stages of winter wheat, and the bias decreased gradually with the closing of winter wheat canopy. Compared with SIM method, MWM method and MSM method both worked more effectively and generated higher accuracy. Among those two multi-source methods, MSM method showed the relatively higher accuracy, and its determinant coefficients R2 was 0.984 and the root mean square error (RMSE) was 0.030 using GF1-WFV images, while the R2 was 0.978 and the RMSE was 0.034 using HJ1-CCD images. The R2 of MWM method was 0.964 and the RMSE was 0.044 using GF1-WFV images, and the R2 was 0.950 and the RMSE was 0.052 using HJ1-CCD images. Comparison indicated that MWM can be utilized to improve the FVC estimation accuracy using GF1-WFV and HJ1-CCD images when there are no matching GF1-PMS images over the same period. This research shows that the synergetic inversion method of winter wheat FVC with multi-source satellite images can generate long time series and high precision FVC products, which can provide the critical data set for vegetation growth monitoring, monitoring of ecological environment and global change detection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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 Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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 Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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.)