Impact of soil and water conservation measuren on catchment hydrological response: a case in north Ethiopia

Impact studies of catchment management in the developing world rarely include detailed hydrological components. Here, changes in the hydrological response of a 200-ha catchment in north Ethiopia are investigated. The management included various soil and water conservation measures such as the construction of dry masonry stone bunds and check dams, the abandonment of post-harvest grazing, and the establishment of woody vegetation. Measurements at the catchment outlet indicated a runoff depth of 5 mm or a runoff coefficient (RC) of 1·6% in the rainy season of 2006. Combined with runoff measurements at plot scale, this allowed calculating the runoff curve number (CN) for various land uses and land management techniques. The pre-implementation runoff depth was then predicted using the CN values and a ponding adjustment factor, representing the abstraction of runoff induced by the 242 check dams in gullies. Using the 2006 rainfall depths, the runoff depth for the 2000 land management situation was predicted to be 26·5mm(RCD 8%), in line with current RCs of nearby catchments. Monitoring of the ground water level indicated a rise after catchment management. The yearly rise in water table after the onset of the rains (ΔT) relative to the water surplus (WS) over the same period increased between 2002-2003 (ΔT/WS D 3·4) and 2006 (ΔT/WS >11·1). Emerging wells and irrigation are other indicators for improved water supply in the managed catchment. Cropped fields in the gullies indicate that farmers are less frightened for the destructive effects of flash floods. Due to increased soil water content, the crop growing period is prolonged. It can be concluded that this catchment management has resulted in a higher infiltration rate and a reduction of direct runoff volume by 81% which has had a positive influence on the catchment water balance. © 2010 John Wiley & Sons, Ltd

Management of consecutive cuts in the production and quality of wintergreen paspalum seeds

The objective of this study was to evaluate the practice of consecutive cuts in the production and quality of Paspalum guenoarum seeds of the “Azulão” ecotype. The experimental design used was in completely randomized blocks with four replications. The treatment included three cuts in succession: zero cut, one cut, two cuts, and three cuts. The variables were: number of total tillers/plant; number of vegetative tillers/plant; number of reproductive tillers/plant; percentage of reproductive tillers; number of racemes/inflorescence; weight of thousand seeds; number of seeds/inflorescence; seed production; forage dry matter; water content of seeds; germination; first germination count; and germination speed index. The largest seed production was obtained with zero cut (850.3, first year and 719.4 kg/ha–1, second year) and one cut (794.4, first year and 627.3 kg/ha–1, second year) with no statistical difference between them. The largest germination percentage was seen with the application of zero (71.0%, first year and 79.3%, second year) and one cut (69.3%, first year and 75.0%, second year). There was a decrease in the production and quality of the seeds of the second cut, especially during the first year of evaluation. The total tillers, the percentage of tillers that went through the reproductive stage, and the number of reproductive tillers are the variables that are most highly correlated with seed production

Influence of time and level of urea application on seed production of paspalum plicatulum at mt cotton, south-eastern queensland

Five levels of urea were applied as single or split dressings in early summer, at floral initiation(about Febraury 14), or at inflorescence exsertion to Paspalumplicatulum cv. Rodds Bay grown in rows on ared-yellow podzolic soil.All components of seed yield-tiller density, tiller fertility, raceme number and seed number, and seed size-were influenced by external nitrogen supply. The effects of adequate nitrogen supply during onedevelopment phase usually persisted subsequently when differences in plant nitrogen concentration haddisappeared. Nitrogen applications during the vegetative and floral initiation stages were most influential.The efficiency of response varied from 5.6 kg additional crude seed produced per kg N at the 50 kg N ha level to 1.2 at the 400 kg N ha -' level. High levels of urea (200 or 400 kg N ha - I)induced lodging and poor recovery of seed at harvest during a wet year, accentuated moisture stress during a dry year, but improved seed viability

Interpretation at Wetland Sites in the Sydney Region

Interpretation of wetland issues and values for the broader community, as well as for students, is regarded as an important strategy toward achieving better wetland management, reversing past degradation, and halting wetland loss along the east coast of Australia, where population pressure has heavily affected these systems. This paper presents the results of a review of interpretive and educational facilities and programs at five wetland sites across the Sydney region to gain a regional perspective on the provision of wetland education and interpretation of wetland ecology and conservation. This review considered goals, range of facilities and programs, wetland themes covered for the general public and in formal educational programs, and evaluation methods. The results are discussed in light of the overall goal of wetland conservation and more detailed goals at individual sites. Goals were found to focus primarily on “public awareness” of wetlands, a goal inadequate to meet the broader goal of long-term protection and conservation. At sites most accessible to the majority of the Sydney population, a considerable discrepancy existed between the aspects of wetland ecology and management presented to school groups and those presented to the general public, making it difficult to meet even the goal of public awareness. </jats:p