Lesser flamingo populations in the Kenyan Rift Valley saline lakes respond to changes in phytoplankton species' composition and densities, behavioural needs, breeding cycles and environmental conditions. The numbers of flamingos are high when the density of blue-green algae Arthrospira fusiformis (Spirulina platensis) is high, stimulating flamingo courtship and display. The numbers decline when lake levels decline, resulting in low phytoplankton densities and a domination by toxic phytoplankton species. In Kenyan saline Rift Valley lakes, heavy metals, pesticides, algal toxins (microcystin), bacterial infection and malnutrition are plausible causes of lesser flamingo mortalities. The production of cyanotoxins by toxic phytoplankton, as a result of declining lake water levels, could be a major factor contributing to the increased mortality of lesser flamingos. Integrated management of the lakes and their catchments is required to ensure the future well-being of the lesser flamingos.

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Abstract:The creation of a World Lake Vision is essential to achieving the sustainable management of the world's lakes. We discuss the value of lakes, how those values have historically led to changes in watershed land-use and population, and how changes have resulted in stresses that impair lake value. Current approaches to lake management at both the local and international level are examined and their shortcomings highlighted. We illustrate how a World Lake Vision, along with the individual lake visions it promotes, can redress the shortcomings of current lake management approaches. Details of the World Lake Vision and the process of its creation are put forth. We end with a critique of the World Water Vision presented at the second World Water Forum in March 2000 from the perspective of lakes and conclude that, in its current form, the World Water Vision provides an inadequate guide for sustainable lake management.

A urine diversion dehydration toilet (UDDT) is a kind of toilet which can be used to recover resources such as nutrients and can also be an option to improve the sanitary situation in low income countries. A structured questionnaire survey, key informant interviews, participatory approaches such as focus group discussion (FGD) and mass gathering were carried out in Kenya to assess social acceptance and scope of scaling up of UDDTs. The results showed that almost all respondents among UDDT users and non-users have overcome social and cultural barriers to accept UDDTs. Most UDDT users were applying UDDT products as fertilizers on their farms. It is recommended to promote coordination and networking of local community based organizations in order to replicate UDDTs.

Cationic surfactants were used to enhance the adsorption of dissolved organic matter (DOM), contained in the effluent of municipal wastewater, onto polypropylene (PPL), a polymeric synthetic adsorbent made from recycled plastics. Both batch and continuous up-flow column experiments were carried out. The DOM, in the form of humic acid, was treated with a range of cationic surfactants, then, adsorption experiments were conducted to evaluate the adsorption of the mixture onto PPL in both its soluble and precipitated forms. This research validated the feasibility of the proposed system in which anionic humic acid is removed from the aqueous phase by forming neutral hydrophobic molecules with cationic surfactants and subsequently by adsorbing them on the hydrophobic surface of PPL.