Assessing irrigation projects performance for sustainable irrigation policy reform

This study examines the socio-economic and financial performances of irrigation projects under the Ogun-Oshun River Basin and Rural Development Authority (O-ORBRDA) in Nigeria. Primary data on the farming activities of the project farmers during the 2001/02 seasons and the projects' records for the period of 1995/96 to 2001/02 were summarised into socio-economic and financial performance indicators. In the Sepeteri Project, a revenue recovery level of 96% was estimated. The project is not financially viable as only 29% of its recurrent expenditure is covered. The farmers do not show commitment to making the project successful. An approximate 67% social capacity level was estimated. The relative irrigation cost and profit indexes do not show sufficient evidence that farmers would prefer irrigation farming to rain-fed farming. The Itoikin Project records a lower revenue recovery level of 75%. The project covers about 50% of its recurrent expenditure. In addition, the farmers do not appear to have a commitment to making the project successful, with a 33% social capacity level. A number of problems may be the causes of unprofitable irrigated cropping. If government increases the subvention, the O-ORBRDA prioritises irrigation service in disbursing the subvention to the projects, and the project manages the risks in the project sites, conscientises and incorporates the intended beneficiaries into managing the projects, the projects would be equipped to supply more irrigation services thereby making it more profitable and encouraging more participation of the intended beneficiaries. This would improve the socio-economic and financial performance of the projects.     

A miniaturized method for fast,simple, and sensitive pesticide analysis in soils

Journal of Soils and Sediments - Organochlorine pesticides (OCPs) like lindane and DDT have been used extensively after World War II until the 1990s. Still, residues of these pesticides can be...     

Commercial single-cell proteins either as sole food source or in formulated diets for intensive and continuous production of rotifers (Brachionus plicatilis)

Commercial Spirulina, Chlorella, and a methanol-grown yeast were tested as sole food source for the rotifer Brachionus plicatilis. Some good results were obtained, but only with medium salinity (18%) and none with seawater (35‰). In comparison with a constant supply of food, different adjustments of the food level to the population density were tested: a proportional and continuous or stepwise adjustment and a less proportional one. The less than proportional adjustment was found to be more advisable for a continuous culture with a daily renewal of a quarter of the volume. The three single-cell proteins appeared to be suitable with 35–55 rotifers produced per ml per day. However, the food conversion was poor: in the best cases 4.2 g of food were required per 10⁶ rotifers produced. In practice, two formulated diets were preferred for mass culture trials in 60-l tanks: the first (P 72) included 40% Spirulina, 40% yeast and different additives; the second was composed of 67% of diet P72 and 33% of the freeze-dried alga Platymonas suecica. The production was 44 and 35 rotifers, respectively per ml per day, with 3.6 and 2.9 g of food, respectively per 10⁶ rotifers,produced. Freeze-dried algae did not appear to be necesary for rotifer production, but the nutritional quality of such rotifers should be investigated.     

Conservation status of two endangered freshwater mussel species in Bavaria,Germany: Habitat quality,threats, and implications for conservation management

1. The freshwater pearl mussel (Margaritifera margaritifera) and the thick‐shelled river mussel (Unio crassus) are relatively widespread across Europe, but are strongly declining and are now protected by the European Habitats Directive. In the course of this study, 20 pearl mussel and 14 thick‐shelled river mussel streams in Bavaria, Germany, were investigated.
2. The mussel populations were mapped to determine population size and age structure. For the assessment of habitat quality, host fish abundance and physicochemical parameters were investigated, e.g. substratum quality, water chemistry, redox potential, and turbidity. Furthermore, potential risks for the populations such as predation or river maintenance were also recorded and assessed.
3. The average population size and recruitment rates of M. margaritifera populations were lower than in U. crassus populations, with 3517 (2.2% juveniles) compared with 5566 (41.4% juveniles) individuals, respectively. On average, 22.3% of particles were smaller than 0.85 mm in diameter at M. margaritifera sites, whereas the mean proportion of fine particles at U. crassus sites was twice as high, at 41.3%. Other parameters such as redox potential or electric conductivity also indicated more favourable habitat conditions in M. margaritifera streams. Unio crassus seems to be less vulnerable to adverse substratum texture and increased nutrient levels than M. margaritifera.
4. The main threats for U. crassus were physical habitat destruction, predation by muskrat, or a lack of host fish, whereas M. margaritifera mainly suffered from siltation leading to a lack of oxygen supply to the interstitial zone, affecting recruitment. Consequently, conservation strategies need to be species‐specific and address stream‐specific reasons for decline. As a basis, accurate and comparable monitoring data are necessary, which implies the standardization of monitoring protocols.

     

Antibiotic resistances of intestinal lactobacilli isolated from wild boars

Acquired antibiotic resistances have been reported in lactobacilli of various animal and food sources, but there are no data from wild boar. The objective was a preliminary examination of the antibiotic resistance prevalence of intrinsically vancomycin-resistant lactobacilli isolated from wild boar intestines and analysis of the genetic determinants implicated. Out of three wild boars, 121 lactobacilli were recovered and grouped according to their whole cell protein patterns. Initial phenotypic screening revealed that all were susceptible to erythromycin (2 μg/ml), but 30 were resistant to tetracycline (32 μg/ml). Based on Randomly Amplified Polymorphic DNA-PCR clustering, 64 strains were selected as representative genotypes for identification and minimum inhibitory concentration (MIC) determination. Partial 16S rRNA gene sequencing identified four species: (i) L. mucosae (n = 57), (ii) L. reuteri (n = 47), (iii) L. fermentum (n = 12), and (iv) L. murinus (n = 5). Most heterofermentative strains displayed low MICs for ampicillin (AMP), chloramphenicol (CHL), streptomycin (STR), kanamycin (KAN), gentamicin (GEN), erythromycin (ERY), quinupristin/dalfopristin (Q/D), and clindamycin (CLI). Atypical MICs were found mainly in L. mucosae and L. reuteri for TET, KAN, STR, AMP and CHL, but except the TET MICs of L. mucosae mostly at low level. L. murinus strains revealed atypical MICs for aminoglycosides, and/or CHL, AMP, CLI. PCR screening detected tet(W) in 12 and tet(M) in one of heterofermentative strains, as well as the aph(3′)-III kanamycin gene in L. murinus. This is the first report showing acquired antibiotic resistance determinants in intestinal lactobacilli of wild boar origin.     

A new approach to ecological land classification for the Canadian boreal forest that integrates disturbances

Traditional approaches to ecological land classification (ELC) can be enhanced by integrating, a priori, data describing disturbances (natural and human), in addition to the usual vegetation, climate, and physical environment data. To develop this new ELC model, we studied an area of about 175,000 km² in the Abies balsamea–Betula papyrifera and Picea mariana-feathermoss bioclimatic domains of the boreal forest of Québec, in eastern Canada. Forest inventory plots and maps produced by the Ministère des Ressources naturelles du Québec from 1970 to 2000 were used to characterize 606 ecological districts (average area 200 km²) according to three vegetation themes (tree species, forest types, and potential vegetation-successional stages) and four sets of explanatory variables (climate, physical environment, natural and human disturbances). Redundancy, cluster (K-means) and variation partitioning analyses were used to delineate, describe, and compare homogeneous vegetation landscapes. The resulting ELC is hierarchical with three levels of observation. Among the 14 homogeneous landscapes composing the most detailed level, some are dominated by relatively young forests originating from fires dating back to the period centered on 1921. In others, forest stands are older (fires from the period centered on 1851), some are under the influence of insect outbreaks and fires (southern part), while the rest are strongly affected by human activities and Populus tremuloides expansion. For all the study area and for parts of it, partitioning reveals that natural disturbance is the dominant data set explaining spatial variation in vegetation. However, the combination of natural disturbances, climate, physical environment and human disturbances always explains a high proportion of variation. Our approach, called “ecological land classification of homogeneous vegetation landscapes”, is more comprehensive than previous ELCs in that it combines the concepts and goals of both landscape ecology and ecosystem-based management.     

Does milk yield reflect the level of welfare in dairy herds?

Under the assumption that milk yield may be reduced in herds with impaired welfare, the present study aimed at investigating whether milk yield could be used as a reliable indicator of welfare. In 125 commercial French dairy herds, the association between the welfare of the herd (evaluated using the Welfare Quality assessment protocol) and cow milk yield was investigated using linear mixed models. Positive associations were identified between milk yield and low aggressions between cows and good emotional state of the herd but there was a negative association with good health assessed through the occurrence of diseases and injuries. These opposite associations resulted in no association with the overall welfare of the herd. Milk yield should not therefore be used as an indicator of overall welfare.