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Preconditions for drainage channels to be anew exploited
2002
Lamsodis, R. (Lithuanian Inst. of Water Management, Vilainiai, Kedainiai reg. (Lithuania))
The paper presents some data collected for various purposes on phenomena, which took place in drainage channels. The data shows a certain one-direction trend of development of these phenomena when slopes of channels are covered with woody vegetation: the intensity of sedimentation of channel's bottom slowed down (Fig. 1); cross section area blocked up by snow decreased (Table 1); concentrations of biogenic and organic (BOD) matter did not show the worsening of water quality (Table 2 and 3). In the most channnels the losses of hydraulic conductivity occuring because of woody vegetation are usually compensated by conductivity reserve of a bigger cross section area caused by a rather large depth of subsurface drainage systems.
显示更多 [+] 显示较少 [-][Technological innovations to increase maize production] | Innovaciones tecnologicas para incrementar la produccion de maiz
1997
Gonzalez Diaz, Luis
[The institutional of the agricultural sciences in Mexico and the university alternative] | La institucionalizacion de las ciencias de la agricultura en Mexico y la alternativa universitaria
1997
Arellano Hernandez, Antonio
[Evaluation of farmer milk production. Case of two communities of Toluca Valley, Mexico State] | Caracterizacion y evaluacion de los sistemas campesinos de produccion de leche. El caso de dos comunidades del Valle de Toluca
1997
Castelan Ortega, Octavio Alonso | Mathewman, Richard W. | Fawcett, Roy | Smith, Anthony | Gonzalez Martinez, Eloy | Burgos Garcia, Ramon | Cruz Juarez, Daniel de la
[Methodological approaches in studing sociodemographic change in rural societies] | Enfoques metodologicos alternativos para el estudio del cambio sociodemografico en las sociedades rurales
1997
Gutierrez Sanchez, Sergio
[The soils in San Felipe del Progreso, Mexico State] | Los suelos del municipio de San Felipe del Progreso, Estado de Mexico
1997
Reyes Reyes, B. Gabriel
[Development theories. An approach and a proposal from the Latin American perspective] | Teorias del desarrollo. Un enfoque y una propuesta desde la perspectiva latinoamericana
1997
Liendo Vera, Isidoro
Technology assessment and transfer: an Australian perspective
1994
Williams, M. | Munro, R. (Department of Primary Industries and Energy, Canberra (Australia). Bureau of Resource Sciences)
Indicators for sustainable agriculture in the Asia-Pacific region
1994
Hamblin, A. (Cooperative Research Centre for Soil and Land Management, Glend Osmond (Australia))
Productivity benchmarks for community-based genetic improvement of Abergelle, Central Highland and Woyto-Guji indigenous goat breeds in Ethiopia 全文
2019
Jembere, Temergen | Haile, Aynalem | Dessie, Tadelle | Kebede, Kefelegn | Okeyo Mwai, Ally | Rischkowsky, Barbara A.
