In the interior mountainous zone locality condition is bad owing to steep topography and few density of forest load. Accordingly, an aerial seeding work is often adopted to early restoration of such a denuded land. However, harsh land discription in addtion to rough executive conditions, that results in execution is not necessarily good. There are number of unsolved points regarding to the causes of poor results. This report deals with the problems on execution and the measuse taken to improve the aerial seeding work. This studies include the experiments on effects of some slurry materials and the investigations in typical executive examples.
(1) The field surveys were taken place in three sites in which there are nine plots altogether with different land discriptions and executive conditions. The sites for investigation were chosen as follow: the KAREKIDO landslide and the HOHKINAGI landslide both of which are located in basin of Ohi river in Shizuoka prefecture and the TOKOZURI landslide in basin of Abukuma river Miyagi prefecture.
(2) From the results on the field observation, the slurry scatting by airplane is lack of uniformity and loss in no small quantities on steep mountain topography. The measures taken to improve the earial seeding work includes two points. One point is taking the better scatting methods. Another is increasing slurry to some extent.
(3) Protection materials of scatting seed-asphalt emulsion and mulching of paper scraps with adhesive matter (SUTABIRA)-have merits and demerits in preventig erosion and growth of plant. Therefore, it must be selected after due consideration on the land description of subject area and time of execution.
(4) In ordinary cases of aerial seeding work, foundation works are often omitted.However, some foundation works such as grading work in small scale and simple retaining works are necessary to stabilize earth surface and to maintain vegetation cover.
(5) As the examples of desirable foundation work, air-mortal scatting for prevention of rockfall and simple retaining of earth which were executed at HOHKINAGI landslide were efficaciously on development of vegetation. These materials were transported by airplane in this site.
(6) To continue additional manures which content much nitrogen leads to a dominant increase of the graminaceae herbs. As a result, it causes that native species and mixed seeding trees cannot grow enough. Accordingly, the additional manures after aerial seeding work must be adequately control according to growing condition of vegetation.
(7) The grasses vagetation in the first stage by seeding needs to be changed to the mixed vegetation with trees and herbs in order to accelerate the plant succession and increase effect of erosion control. As this adequate measure, it was cosidered as follow: sellection on adaptable species in time of seeding, improvement on system of scatting technique and better-ment on system of additional manure management.

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