Territorial analysis of the diffusion of organic farming in France: Between heterogeneity and spatial dependence

This paper discusses the development of organic farming (OF) in France from a collective point of view by focusing on the spatiotemporal diffusion of OF and considering different types of production. Based on the data on aid granted between 2007 and 2010 for conversion to OF (COF), the spatial dynamics of conversion is examined with regard to the distinctive capacities of micro-territories to accommodate farms engaged in OF to a greater or lesser extent. The hurdle model is applied to varying types of COF aid, which are related to different production systems. This allows for both the characterization of the geographical extent of the contracting of COF aid and its local intensity measured by the number of contracts within micro-territories. The spatial structure of COF contracting can be explained both by economic factors relating to the orientation of production systems and by phenomena of spatiotemporal dependence, which demonstrate the importance of producers’ experience and of collective capacities. We can therefore speak of path dependence in relation to the establishment and maintenance of market access capabilities and social networks, which determine the potential and effectiveness of the development of organic agriculture at the micro-territorial level.     

Differences in biomass production and carrageenan yields among four strains of farmed carrageenophytes in Northern Bohol,Philippines

Comparative studies on the biomass and carrageenan production of two strains ofEucheuma denticulatum and two strains ofKappaphycus alvarezii were made to assess the seasonality in their production capacities.The high and similar refined carrageenan (RC) yields (43–53% of dry wt.) of the four strains in the first cropping season (June–October) coincided with their high biomass production with plants averaging from 1.1 to 1.8 kg each at harvest. The poor RC yields (21–33%) recorded in the second cropping (October–February) coincided with their season of low biomass (av. wt: 0.34 to 1.0 kg). The four strains, however, recorded contrasting performance in the third cropping season (February–July) with the twoE. denticulatum strains recording high RC yields (43 and 42.5%) together with high biomass (av. wt: 1.5 and 1.6 kg) in contrast to the low RC yields (30 and 39%) and low biomass (av. wt. 0.21 and 0.28 kg) of the twoK. alvarezii strains. Records for semi-refined carrageenan (SRC) yields in the second and third cropping seasons were quite consistent and similar for the four strains (42–55%), except in the second cropping where the twoK. alvarezii strains recorded low SRC. These differences in production potentials highlight the need for cropping management of the four strains to improve their cropping performance.     

Gender participation in sheep and goat farming in Najran,Southern Saudi Arabia

Sheep and goat farming is a major source of income in the rural areas of Al-Wadiah in Najran region of Southern Saudi Arabia. The study aims to identify the factors and parameters that influence gender participation in sheep and goat farming. Data were collected by interviewing 167 high school students, including 70 male and 97 female students, in Al-Wadiah, by using the simple random sampling technique. Data were statistically analyzed to establish the relationship between gender and participation in sheep and goat farming. The study revealed significant differences between the two genders, for instance, male herders were more experienced, received more benefits, showed greater interest in discussions on topics related to sheep and goat farming, followed information from TV and radio, and received more services offered by veterinary clinics, which proved more beneficial for them. On the other hand, female herders received fewer services, and the veterinary clinics proved less beneficial for them. However, the correlation between the participation of both genders in sheep and goats management was non-significant toward the statement “feeling ashamed of participating in sheep and goat farming.” Generally, sheep and goat rearing proves more beneficial for male participants than female participants, owing to their greater experience and interest in livestock farming. Moreover, they receive more benefits from TV, radio and veterinary clinics to maintain better health of their livestock. Both male and female herders contribute equally to sheep and goat farming by limiting the time spent on their daily routine. This study would enable policymakers and planners to develop more strategies and extension education programs to overcome the identified barriers and improve the livelihood of herders through their enhanced participation in remote areas.     

A spatially explicit representation of conservation agriculture for application in global change studies

Conservation agriculture (CA) is widely promoted as a sustainable agricultural management strategy with the potential to alleviate some of the adverse effects of modern, industrial agriculture such as large‐scale soil erosion, nutrient leaching and overexploitation of water resources. Moreover, agricultural land managed under CA is proposed to contribute to climate change mitigation and adaptation through reduced emission of greenhouse gases, increased solar radiation reflection, and the sustainable use of soil and water resources. Due to the lack of official reporting schemes, the amount of agricultural land managed under CA systems is uncertain and spatially explicit information about the distribution of CA required for various modeling studies is missing. Here, we present an approach to downscale present‐day national‐level estimates of CA to a 5 arcminute regular grid, based on multicriteria analysis. We provide a best estimate of CA distribution and an uncertainty range in the form of a low and high estimate of CA distribution, reflecting the inconsistency in CA definitions. We also design two scenarios of the potential future development of CA combining present‐day data and an assessment of the potential for implementation using biophysical and socioeconomic factors. By our estimates, 122–215 Mha or 9%–15% of global arable land is currently managed under CA systems. The lower end of the range represents CA as an integrated system of permanent no‐tillage, crop residue management and crop rotations, while the high estimate includes a wider range of areas primarily devoted to temporary no‐tillage or reduced tillage operations. Our scenario analysis suggests a future potential of CA in the range of 533–1130 Mha (38%–81% of global arable land). Our estimates can be used in various ecosystem modeling applications and are expected to help identifying more realistic climate mitigation and adaptation potentials of agricultural practices.     

Gracilaria-Mytilus interaction on a commercial algal farm in Chile

Mytilus chilensis is an invertebrate that competes for space with the alga Gracilaria chilensis in farmed areas in Chile and, for this reason, is considered a contaminant organism. Mussel beds are considered to play a role in the regeneration of nitrogen and, as a consequence, they could be an important source of ammonium for the algae. In this study, we manipulated the mussel cover in experimental plots, creating replicated areas with 0%, 30% and 60% coverage. In half of the plots the mussels were killed with a gas torch so their effect would be mechanical, without nutrient regeneration. After 15 days, each plot was planted with 12 G. chilensis bundles (100 g each) per square meter. Ammonium concentrations increased significantly in the waters around the mussel bed in contrast to areas without mussels or dead mussels. Mussel cover had a significant negative effect on the length of the G. chilensis bundles planted in the experimental plots. However, no significant differences were detected between experimental quadrats with live mussels and those with dead mussels during a 5 month period. These results indicate that the mechanical effect of the mussel can, to some extent, be responsible for the decline in G. chilensis abundance in farms where mussel beds have been established.     

Estimates of seasonal nitrogen fixation of annual subterranean clover-based pastures using the15N natural abundance technique

Annual pasture legumes play a key role in ley farming systems of southern Australia, providing biologically fixed nitrogen (N) to drive the production of the pastures as well as subsequent crops grown in rotation. Seasonal inputs of biologically fixed N in shoot biomass of the subterranean clover (Trifolium subterraneum) component of grazed annual pastures were assessed using the¹⁵N natural abundance technique and appropriately timed sampling of herbage dry matter (DM) for N accumulation. At three study sites spanning a gradient across the Western Australian wheatbelt from 300 to 600 mm annual rainfall the performance of the clover and non-legume herbs and grasses was examined as paired comparisons involving two management treatments expected to give contrasting effects on pasture productivity, botanical composition and N₂ fixation. The proportion of clover N derived from atmospheric N₂ fixation (%Ndfa) ranged from 65 to 95% across sites, treatments and sampling times. Amounts of fixed N accumulated in clover shoot biomass ranged from 50 to 125 kg ha⁻¹, and paralleled trends in clover production. Substantial increases in pasture production in high yielding treatments generally occurred without decrease in %Ndfa, suggesting that N₂ fixation was essentially non-limiting to performance of the clover component. Seasonal profiles for accumulation of fixed N were skewed towards the late winter and spring period, particularly in low plant density pastures following a cereal crop. There were seasonal, site and treatment-specific effects on the proportion of clover and non-legume pasture components and consequently clover yield and N₂ fixation were variably affected by competition from non-legume species.     

CCC浸种对小麦生长性状的影响

ＣＣＣ浸种的效应与其浓度密切相关。１０％的浓度明显降低出苗率;浓度低于５％对出苗率无影响。在０．１％－１０％之间,随浓度增高,茎叶干重降低,而根系干重增加。增加根系总长度的效果以０．１％－３％的浓度最好。浓度在５％范围内,叶绿素含量随浸种浓度的的升高而增加。浓度高于１％时叶面积减小。全面权衡,旱地小麦ＣＣＣ浸种最适宜的浓度为１％。     

Cultivation of Gracilaria on the sea-bottom in southern Chile: a review

This review contains information about the cultivation techniques, strategies, problems and new challenges faced as well as an economic analysis of the income-producing capacity of Gracilaria farming, considering the variability of environmental systems where this alga is cultivated in southern Chile. The development of Gracilaria farming in Chile was made possible by an increased market demand, as well as the existence of basic knowledge that permitted the management of wild stocks and the initiation of cultivation practices. Subtidal cultivation systems appear to be more productive than intertidal systems and are less susceptible to wave action than intertidal cultivation areas. In relation to farming practices, this difference implies that planting and harvesting methods and strategies vary between habitats where cultivation is being carried out on a commercial scale. Several problems such as the environmental impact of different cultivation methods adopted by the farmers, the management of contaminating organisms and strain selection appear to be important and new areas for future research. Finally, an analysis of the income-producing capacity indicates that environmental differences also have important consequences for the management strategies of Gracilaria cultivation.