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Farm Type (farm + type)
Selected AbstractsThe area requirements of an ecosystem service: crop pollination by native bee communities in CaliforniaECOLOGY LETTERS, Issue 11 2004Claire Kremen Abstract Managing ecosystem services is critical to human survival, yet we do not know how large natural areas must be to support these services. We investigated how crop pollination services provided by native, unmanaged, bee communities varied on organic and conventional farms situated along a gradient of isolation from natural habitat. Pollination services from native bees were significantly, positively related to the proportion of upland natural habitat in the vicinity of farm sites, but not to any other factor studied, including farm type, insecticide usage, field size and honeybee abundance. The scale of this relationship matched bee foraging ranges. Stability and predictability of pollination services also increased with increasing natural habitat area. This strong relationship between natural habitat area and pollination services was robust over space and time, allowing prediction of the area needed to produce a given level of pollination services by wild bees within this landscape. [source] Impacts of Alternative Manure Application Rates on Texas Animal Feeding Operations: A Macro Level Analysis,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2008E. Osei Abstract:, An integrated economic and environmental modeling system was developed for evaluating agro-environmental policies and practices implemented on large scales. The modeling system, the Comprehensive Economic and Environmental Optimization Tool-Macro Modeling System (CEEOT-MMS), integrates the Farm-level Economic Model (FEM) and the Agricultural Policy Environmental eXtender (APEX) model, as well as national databases and clustering and aggregation algorithms. Using micro simulations of statistically derived representative farms and subsequent aggregation of farm-level results, a wide range of agricultural best management practices can be investigated within CEEOT-MMS. In the present study, CEEOT-MMS was used to evaluate the economic and water quality impacts of nitrogen (N) and phosphorus (P) based manure application rates when implemented on all animal feeding operations in the State of Texas. Results of the study indicate that edge-of-field total P losses can be reduced by about 0.8 kg/ha/year or 14% when manure applications are calibrated to supply all of the recommended crop P requirements from manure total P sources only, when compared to manure applications at the recommended crop N agronomic rate. Corresponding economic impacts are projected to average a US$4,800 annual cost increase per farm. Results are also presented by ecological subregion, farm type, and farm size categories. [source] The effectiveness of volunteer nest protection on the nest success of Northern Lapwings Vanellus vanellus on Dutch arable farmsIBIS, Issue 4 2008STEVEN KRAGTEN Clutches of ground-nesting farmland birds are often destroyed by farming operations, resulting in insufficient reproductive success and subsequently declining populations. The aim of this study was to investigate whether volunteer nest protection can enhance nest success of ground-nesting birds. The study compared nest success of protected and unprotected Northern Lapwing Vanellus vanellus nests over 2 years on arable farms in the Netherlands. Because of different crop management, nest success of ground-breeding birds might differ between organic and conventional arable farms. The effectiveness of volunteer nest protection was therefore investigated on both farm types. Although nest protection significantly reduced nest loss due to farming operations, there were no significant differences in total clutch survival of protected and unprotected nests. However, sample sizes of unprotected nests, and protected nests on organic farms, were relatively small, which may have reduced statistical power. There were indications that protected nests were predated or deserted more often. We recommend exploring different ways to improve the effectiveness of volunteer nest protection through a further reduction of nest loss due to farming operations and predation. [source] Asian carp farming systems: towards a typology and increased resource use efficiencyAQUACULTURE RESEARCH, Issue 6 2002C G J Michielsens Abstract Resource use efficiency in Asian carp farming systems is analysed based on a survey of 2493 farms of nine countries. Multivariate classification of farms by intensity and diversity identified six farm types: four types of specialized aquaculture farms at different levels of intensity, and two types of integrated agriculture,aquaculture systems. Pond-based, specialized semi-extensive systems (using mainly inorganic fertilizers and feeds of off-farm origin), and integrated semi-intensive systems (using feeds and fertilizer of both on and off-farm origin) are by far the most common types, accounting for 59% and 27% of all farms respectively. Specialized semi-extensive systems also show the highest protein and nutrient (N and P) use efficiencies, and among the highest labour use efficiency. Super-intensive cage farms are less efficient in nutrient and labour use, but provide very high returns to land and capital investment. On average, the aquaculture components of integrated agriculture, aquaculture systems are less nutrient, land, and labour efficient than specialized semi-extensive systems. Integrated semi-extensive systems (using organic fertilizers of on-farm origin) are particularly inefficient across all indicators. Hence in practice, gains in overall resource use efficiency through on-farm integration with agricultural production are constrained by the relative inefficiency of the aquaculture subsystems on integrated farms. Although such systems can likely be improved, integration as such is not a panacea to increasing resource use efficiency. Wide variation in resource use efficiency within all systems indicates potential for substantial efficiency gains through improved management regardless of the fundamental choice of system. [source] | ||||||||||