No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss...

8
腈腊腋腃腐腀腁腎腌腍腇腂腑腆腏腄腉腅 膠臛膄膘*膗膍膦膺膧**Janya SANGARUN***臂膁腹臜膃膙* E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*, Machito MIHARA**, Janya SANGARUN*** and Yukiko DOKIYA* * Tokyo University of Agriculture and Technology, -/2 Saiwaiocho Fuchuoshi Tokyo, Japan ** Tokyo University of Agriculture, +++ Sakuragaoka Setagayaoku Tokyo, Japan *** Mae Fah Luang University, --- Moo. +. Tasud subodistrict, Muang district, Chiang Rai, Thailand Abstract The e#ect of grass strips on the reduction of sediment and eutrophic salt loads is been widely recognized. However, there is very little knowledge of the e#ect of grass strips on the reduction of sediment and eutrophic salt losses. Attention was hence focused on the investigation of what grass strips should be managed. Soil suspension was supplied to the experimental plots under simulated rainfall. During the experiment, surface discharge and sediment concentration were measured. In order to observe the e#ect of grass strips on the reduction of sediment loss, the di#erence between the amounts of sediment supplied and sediment loss was investigated in each plot. While the sediment concentration and load from the bare upland field exceeded the concentra- tion and load of the soil suspension supplied, the sediment concentration and load from all the grass strips were lower than the concentration and load of the supplied soil suspension. The di#erence between the sediment supplied and the sediment loss from the cutting weeds plot for pest control was approximately equivalent to that of the plot with the natural weeds. Therefore, it was concluded that cutting weeds for pest control can be applied to the grass strip for reduction of the sediment loss. There was little di#erence between the reduction of the sediment loss from the plot with 2** stems/m , and that from the plot with +,.2* stems/m , of Tall Fescue (F. arundinacea). However the plot with ,,--* stems/m , of Tall Fescue was e#ective for the reduc- tion of sediment loss comparing with 2** stems/m , and +,.2* stems/m , . It suggests that stem density for grass strips should be maintain ,,--* stems/m , to control soil loss from upland field. Key words : Grass strips, Sediment loss , Surface runo#, Upland +腇腅腈腆 臇膹腈腡腙臂膢臟臕膪膎腙膏腼臀腇腠腛腷臇臀腗腶膳 膕腕腍腓膣膬膴腙膮膻腇腠腛膀臞腉膞膛腌腤腓腆腣腭腪腲腫腮 Pennisetum alopecuroides腄腁 腰腭腮腂 Vetiveria zizanioides腙腽腥臐膡臔臘腙臄膑膯腘腸腒 腓腶臢腘膔臈腍腓臔臘腙膥膤臖膜腟臐膡腈腡腙臂膢臟 臕腙膪膎腘臝腆腣腋腕腉臒膒腌腤腓腆腣 臡臙+33/Dalton +330腄腀 腐腑腍臍腙膉腆膣膬膴腔腚膴臅腔 腙臂膢腙臑膱腚腜腕腦腖膂膵腔腊腏膣膬膴膠臟臌腔腙 臂膢腙膲膭腘腠腣臟臕臂臠腙膪膎腉臚臀腕腌腤腓腆腣腶臓腶膿臍腙膣膬膴臅腔臟臕臂膢腥臑膱腎腣膝腝腞腗 腌腤腓腆腣膟臘膾 0* m 腙臉膹臐膡腘腇腆腓腺膸臌 +* m 臍腙臗膰膴腥膮膻腎腣腋腕腘腠腢臆臏膋臟臕臂 J. Jpn. Soc. Soil Phys. 臂膢腙臎臞膫 No. 22, p. +++2 ,**+* 臃膇臇膏膶腼 +2-2/*3 臋膼膚膐膽 -/2** 臃膇臇膊膶腼膹腵腾膈腻腼臌 +/02/*, 膩臁膷膌膖膅 +++*** 腱腩腯腧腂腳腨腴膶腼臇腼臌 腬腩膓腉腁腋腁腊 : 膣膬膴臟臕臂臠臊臘臟膆膨臉膹

Transcript of No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss...

Page 1: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

���������� �����

����*�����**�Janya SANG�ARUN***��� ��*

E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field

Takashi UENO*, Machito MIHARA**, Janya SANG�ARUN*** and Yukiko DOKIYA*

* Tokyo University of Agriculture and Technology, -�/�2 Saiwaiocho Fuchuoshi Tokyo, Japan

** Tokyo University of Agriculture, +�+�+ Sakuragaoka Setagayaoku Tokyo, Japan

*** Mae Fah Luang University, --- Moo. +. Tasud subodistrict, Muang district,

Chiang Rai, Thailand

Abstract

The e#ect of grass strips on the reduction of sediment and eutrophic salt loads is been widely

recognized. However, there is very little knowledge of the e#ect of grass strips on the reduction

of sediment and eutrophic salt losses. Attention was hence focused on the investigation of what

grass strips should be managed.

Soil suspension was supplied to the experimental plots under simulated rainfall. During the

experiment, surface discharge and sediment concentration were measured. In order to observe

the e#ect of grass strips on the reduction of sediment loss, the di#erence between the amounts of

sediment supplied and sediment loss was investigated in each plot.

While the sediment concentration and load from the bare upland field exceeded the concentra-

tion and load of the soil suspension supplied, the sediment concentration and load from all the

grass strips were lower than the concentration and load of the supplied soil suspension. The

di#erence between the sediment supplied and the sediment loss from the cutting weeds plot for

pest control was approximately equivalent to that of the plot with the natural weeds. Therefore,

it was concluded that cutting weeds for pest control can be applied to the grass strip for reduction

of the sediment loss. There was little di#erence between the reduction of the sediment loss from

the plot with 2** stems/m, and that from the plot with +,.2* stems/m, of Tall Fescue (F.

arundinacea). However the plot with ,,--* stems/m, of Tall Fescue was e#ective for the reduc-

tion of sediment loss comparing with 2** stems/m, and +,.2* stems/m,. It suggests that stem

density for grass strips should be maintain ,,--* stems/m, to control soil loss from upland field.

Key words : Grass strips, Sediment loss , Surface runo#, Upland

+� � � � �

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����JU56V%0WX34'56 =YZ( +33/(Dalton�( +330>7 [\&( ]�^5)*+_`+a_���bc`d%efgh_ij( )*+��k_���lmJ�6��n���0o�%34'567"p( "q]�)*+a_���Bbcr6stu!34'567 vFw 0* m�x�CDJ�5'( yzkJ +* m]�{|+B,-r6V%J�}~����

J. Jpn. Soc. Soil Phys.

���/�No. 22, p. ++�+2 �,**+�

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Page 2: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

�� ,-�� ���������������� �.1� ��� 0� ������������ �Uusi�Kamppa and Ylaranta, +33,�� ���� -1m������� �� � ..- m�� 2./ m���!�"#�$%&���'� ()��*����� /*�+,�-.� ������/������0�-.��������% �Parsons1� +33.�� &�1�23�'� 45678��9:�"#�$%&�;� 9:�������<���=�>������%?�@�A�����1�&�1�23;�'BCDE���F�9:�������G�"�H���IJ�KE�� �Ghadiri1� ,***�� 9:�� ,* cm��� .* cm��LM9:��" ��NO9:� �1���� IJPQ�����9:����NO9:��,�!��<�"R�S1��0��� 9:��; �<�"R�T�UVFDW������%�#�W��%� 9:���� X�� !:��� Y$Z[� G�� ()PQ� 9:\�]^_%`�&�ab�'c�de$%�fH1�%�g� �1F%23�(����'� �<����)hF9:��i'*�j$%23 k�C��lD'��H%� ��� ��<�mno+����� �����pq���_%`,�rF1s,tr`,��u%���� ���-�����p.$%&��/1D�����' �vw� ,0� +333�� �<���xy�=�>��-����������0)h;B%&�0A����%�z{|1F23���� }~4���c!�5��67$%�g� }~4��"LM9:��.�8�.� �<���=�>����xy�)h9 $%���:;�%� .D.� }~4���67.�c! ;~<�=�">H%?�@��u%:A����B����FW�'� ��,�CD0:�%�g� !�'&�c!Y$�.l.lEF�F% �!G1� +33.�� .��W�� LMZH�9:��rF1s!�'&�Y$�KE��9:���%�<�����"I�%� �F;B%���� �<����)hF9:��!:���i'*�j.� ���F�ZH�B%� G���-�mnJ

�"KL�.��M!3;B'� NO�'���<mnP�&��� �1���%768���� �F. ar-

undinacea� &�QR�S�W� � TXO��u%/U34���� +*** stems/m,+������% �;��V����� +33*� �� ��.��<����)hF9:��!:������C�� ����W$%EF�B%�323; NO()PQ�;9:����<_%`"�R��%IJ"K�� X���@P�&"KL�.�9:Y$�9:���%�<��� ��>H%de"�W.�� XY�!:���¡F%768����9:�" ��� �������Z.�9:��!:��"�W.��

,� � � � �

323�IJ [¢;�.£\���NO()#]"]H�G�^¤¥J_" ��KW��¦§�+�¨©�' Plot �ª�;B%� Plot � *./m� � ,m� G�«� +0¬;B'� `­b®ab¯c;°�.��-±�"²� *.,m;³�.�� ³��<��@ LiC�´d�� +..*�;BW� �-�+�� Plot � e�ZH"µ¶.� Plot ���� Plot � �<"³�· -¸¹º4�.�� c!"67���LM9: Plot�.�� ��� -¸¹º�4�·� Plot ��9:"�-�D1 +*

���+ NO()»��¥J_Photo. + Simulated rainfall system and experi-

mental plots.

��+ �<�<$@Table + Physical properties of soil

Specificgravity

Particle size distribution* (�)Dispersionratio (�)

Ignitionloss (�)

Soiltexture

Gravel Coarse sand Fine sand Silt Clay

,40* *4* 241 -*40 ,/40 -/4+ 14* +.4* LiC

* International methods.

�<�<$@ X 22¼ �,**+�12

Page 3: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

cm�������� � Plot�� ����� Plot���������������� !"#�$%���& Plot�'(")�*+,-./0 1rd)� 23,%

4'5�63/0�7�,�8��� & Plot9,*+,-./0 *.2,�*.21 1g/cm-: ,;<9�=>�� &Plot�'?@ +** cm,AB9,63/0CD� +*EFGH?� 3/�,IJAK�'("LMN�63/0O�

��, PQR,23'5�STUVTable , Vegetation and management in plots

Plot Vegetation (scientific name) rd(g/cm-)

Density of stems (W+)(stems/m,)

Management

Plot I

Plot II

Plot III

Plot IV

Plot V

Plot VI

None

Weed (10� with Setaria viridis)

Weed (2-� with Setaria viridis)

Tall Fescue (F. arundinacea)

Tall Fescue (F. arundinacea)

Tall Fescue (F. arundinacea)

*42-

*421

*42-

*42,

*42.

*42-

X,5.2* 1,5//*:,5-2* 1,52.*:

2**

+5.2*

,5--*

Bare

Cutting

None

None

None

None

W+ : , weeks after the cutting weed of plot II.

��+ YZ[\]^_�'("`a7bcde#'5�cf*# 1gh23 Plot �����i:

Fig. + Changes in cumulative surface runo#

and soil loss under simulated rainfall

(before the cutting weed in plot II).

��, YZ[\]^_�'("`a7bcde#'5�cf*# 1gh23 Plot �����jk:

Fig. , Changes in cumulative surface runo#

and soil loss under simulated rainfall

(just after the cutting weed in plot II).

lm : 23n�o?�pq*+,c�rstu 13

Page 4: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

�� ���� Plots �� ����� ������/������������� �� Plot � �� Plot

�� �!"#�$�%&'()*+, -Setaria

viridis. /0110�� 2-��23456��� Plots �������789:5;<=>� ��01,.2*

stems/m,� ,-2* stems/m,�%?�/� 789: ,@AB� ��� Plot ��� ,//* stems/m,�C�DEFGH�� Plot ��� ,2.* stems/m,�IJK�� L��� 789:��8 Plot �� M&���NO/�PQ�����RS�&�TUVWXYZ5[\K� Plots �� �� �����]�^� 2** stems/m,� +.2* stems/m,� ,--*

stems/m,�%?�� [\_� ��`��Q�&a�b�c�bd/ +*** stems/m,e��%&L�f��Plot �/[\_� M&�8ghi�j�k5llmn8� Plots �� �/j�k5on?��&L�/Sf

&�0 Plot� M&pq��4�5 ,.rAs���K�B� .2 mm/h�tuv�� -*4A�w_tuxy5;�� zg�{��� �|p�� }~����5��K��w_tu������5 + mS/cm�m���K��!����;?�� Q�������&pq����5��&��� .2 mm/h�w_tu��m�� tu�� +/

4��B�8tu���� +/4A� Plot�o�f�pq���5 *.*- dm-/s���QH�zg�{����|p�� }~����5��K�� pq����� Plot����pq�� ¡¢p�£�5J¤�¥4���K���¦�5x�K�B��� ��� §�K¨/����5©ªK���¦�5«��h?�� ��¦� �������m��� USLE`�¬y� M& +331­0®�¯°r�±²³��´µ -Mihara� ,**+. �j¶

��- w_tu��m� M&�·zg�{�� ���|p� -���� Plot �789: ,

@AB.Fig. - Changes in cumulative surface runo#

and soil loss under simulated rainfall (,

weeks after the cutting weed in plot II).

��. w_tu��m��pq����©ª�¸<�·zg�{�� ���|p� -����Plot �789:=B.

Fig. . Changes in cumulative surface runo#

and soil loss under simulated rainfall

with additional suspended water supply

(just after the cutting weed in plot II).

pq�¹�º » 22¼ -,**+.14

Page 5: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

������ ���� ������� +1,0**�,+,-** g/m-���������

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+� �� !"#$%&'(�)�*+,- Plot �.�� ! Plots �� ��/012345#$%&67�89:��)':;<�+�-#=���,- Plot �#$%&��6=��)':��� !Plots �� �#>?�@�AB��;=��� CD�67�89:$EF�)':G Plot �H Plots �� �;IJAKL���M���� ! Plot �#$��� NOPQ ,RST���6=��)':�UVWS 3/��XY�H -/- g/m-��O� Plot ��XY� ,*0 g/m-

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#$��� /012345�'(� 9;����b��c#$%&67�89:� �)':;<�.� /#=��� ,- Plot �#$%&��6=��)':���� ! Plots �� �#>?�@�AB��;=�� ���'(� 9�� 9��;KL��� bd��Plot�Kefg���� 9��5#EO,-W�hiH!j��k.lmgd&� �f�� �� !Plots �� �#$���� '(� 9��5#n��)':����Kop&G��� ���� 9��;5L��� E��� !"#EO��� 9q�'(Hrsd�._`�J�� M�� CD��)':�� �� ! Plot ��NOPQaT$EF ,RST#$��� Plots �� �.G#,- Plot �;IJA5L���t�c345#$��� �� !"�NOPQ�uv#

��/ /012345��'(� 9�wx#nyCD67�89:$EF�)': z�� !Plot �NOPQ ,RST�

Fig. / Changes in cumulative surface runo#

and soil loss under simulated rainfall

with additional suspended water supply

(, weeks after the cutting weed in plot

II).

��0 /012345#$%&CD67�89:$EF�)': z{|}~����

Fig. 0 Changes in cumulative surface runo#

and soil loss under simulated rainfall

(Tall Fescue).

�� : !";����-'(�����*+ 15

Page 6: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

���������� �������������� ����� +* cm����� ��� ���!"#$������ �%&�'��()*+,

,- .�/0�12�3456789���� :�;<�=>.�/0�12�3456789���� ��� ?@ABCD EFABGHI��JKL�;MCD!NO+ PQ�0� 1-,

Plots � P2** stems/m,-� � P+.2* stems/m,-� �P,--* stems/m,- �?@ABR� :�S0�T�;<UV� WXYZ 3/���[\�]^0,/ g/m-� 0.. g/

m-� +/- g/m-�'O+, �_L` /��V Plot ��Plot ���Z��_aVbc�d2�O+�� .�/0 ,--* stems/m,� Plot �� :�;<UV� Plot

� EF Plot ���Z��_L` /���_a�bc�d+, �����Ee� Plot �� :�S0�T�;<U�f� Plot!ghiIj������O+ PQ�0-, �+� ABGHI�JKL!;M�k+CD� ��V� JKL�;M�lO�ABmnEe +2

opqr�;<U�st*+, Plots �� �� :�S0�T�;<UV�_L` /���_a�bc�d2�O+��u*�� Plot ��V Plots �� ���_a�bc�d+, .�/0 2** stems/m,v,--* stems/

m,� Plots �v�� :�S0�T�;<UV� ;M�k+JKLS0!ghiIjO+����� wx@� :��e�yz�{`�'� +*** stems/m,

|0�.�/0����V;<�� ����'e������CDGH�V� ,--* stems/m,|0�.�/0!st�k����� }!~��d�����h+,

��1 ?@ABGHI��JKL����l�����;�LU EF;<U P3456789-

Fig. 1 Changes in cumulative surface runo#

and soil loss under simulated rainfall

with additional suspended water supply

(Tall Fescue).

��2 ���� Plot II�e���r� :�a*�h;<U

Fig. 2 Comparison between amount of soil

supplied and of soil loss under simu-

lated rainfall with additional suspended

water supply (just after the cutting

weed in plot II).

���� � 22� P,**+-16

Page 7: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

-� ��������� ��������������������

! Plot"#$%��� &L,� "#��������'()*�� &L+� +����,-+������� &L,�L+� ./0� ! Plot��1(�������+2�23+* �4�,52�2 �4�,67 89 Plot �����:����

���; 1+3 g/m, .<�=>-+.7 89?@�:���;ABC(DEF.��G�,5 H, IJKLM &Plot �� �'NO7PQRS+TU,KLM&Plot �� ����: �������;!VW/02

g/m, W/3*g/m,�X7 ��YZ[�\.]^�;_= .`�abF.��G=c.;d"U,5 efghijkKLM�X( Plots � &2** stems/m,� �&+.2* stems/m,� ����: �������:.`�W0,,g/m, �XU,; l`mLnop� Plot �

&,--* stems/m,� �������:W00. g/m, �X7 Plots � ���q�'7r-;<�"U,5cc."# st�uv�X( +*** stems/m,wo'7`st+Ax� mLno ,--* stems/m,wopno�efghijk+yzC(. ���YZ�{|�X(.}~��,5

.� � � � �

c�H� �9"#�EC(��YZ�{|_KLM�7�:����q#���_�5 �c� ����:�������+��.�,�mO7PQ;KLM�'(��YZ�[���(��+�q(,� ���F���+��� ������������+Plot� "#)*� ¡¢�£��'N���+¤/�,5 9¡¢'7 +* cmp¥��mO7PQ+TU,KLM�'N¦O7PQKLM�: Plot"#���. Plot� "#����'7)*�,�

��3 IJKL Plot IIO7PQ , §¨©��1(�������

Fig. 3 Comparison between amount of soil

supplied and of soil loss under simu-

lated rainfall with additional suspended

water supply (, weeks after the cutting

weed in plot II).

��+* efghijkKLM��1(�������

Fig. +* Comparison between amount of soil

supplied and of soil loss under simu-

lated rainfall with additional suspended

water supply (Tall Fescue).

ª« : KLM+��,¬9���Er­®¯ 17

Page 8: No. 22,p.++ +2 · * ** Janya SANG ARUN*** * E#ect of Grass Strips on Reduction of Sediment Loss from Upland Field Takashi UENO*,Machito MIHARA**,Janya SANG ARUN*** and Yukiko DOKIYA*

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runo#, The Role of Erosion and Sediment Trans-

port in Nutrient and Contaminant Transfer, pp.

2-�3+, International Association of Hydrological

Science Press, U.K..

Mihara, M. (,**+) : Nitrogen and phosphorus losses

due to soil erosion during a typhoon, Japan,

Journal of Agricultural Engineering Research,

12 (,) : ,*3�,+0.

Uusi�Kamppa, J. and Ylaranta, T. (+33,) : Reduction

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on vegetated bu#er strips, Agric.Sci.Finl. + : /03�/1/.

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and sediment removal by grass and riparian

bu#ers, Environmentally sound agriculture pro-

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