INSTRUCTION: Answer question ∈ relation to text.
TEXT
Differences of floral resource use between honey bees and wild bees ∈ an intensive farming system
Bees provide an essential pollination service for crops
and wild plants. However, substantial declines ∈ bee
populations and diversity have been observed ∈Europe
and North America for the past 50 years, partly due to the
[5] loss of natural habitats and reduction of plant diversity
resulting from agricultural intensification. To mitigate
the negative effects of agricultural intensification, agri-
environmental schemes (AES) have been proposed to
sustain bees and other pollinators ∈ agrosystems. AES
[10] include the preservation of semi-natural habitats such as
grasslands, fallows, woodlots, hedgerows or set-aside
field margins. However, empirical evidence suggests that
the use of those semi-natural habitats by bees may vary
greatly among bee functional groups and may further
[15] be influenced by the presence of alternative foraging
habitats such as mass-flowering crops. The present study
sets out to investigate whether the three bee groups
typically targeted by AES (honey bees, bumble bees
and other wild bees) differ ∈ the way they use those
[20] semi-natural habitats relative to common mass-flowering
crops (oilseed rape, sunflower, alfalfa)∈ an intensive
agricultural farming system. A clear segregation pattern ∈
the use of floral resources appeared between honey bees
and wild bees, with the former being tightly associated
[25] with mass-flowering crops and the latter with semi-natural
habitats. Bumble bees had an intermediate strategy and
behaved as habitat generalists. Therefore, it would be
sensible to treat the three bee groups with distinct AES
management strategies, and to further consider potential
[30] effects on AES efficiency of alternative foraging habitats ∈
the surrounding. This study also stresses the importance
of native floral resources, particularly ∈ semi-natural
herbaceous habitats, for sustaining wild bee populations.
http://www.sciencedirect.com/science/journal/01678809. Acesso em set 2013.
The sequence ∈ which information is presented ∈ text is:
