Balancing Bees and Livestock: Pastoralist Knowledge, Perceptions and Implications for Pollinator Conservation in Rangelands, Northern Tanzania

Insect pollinators provide numerous ecosystem services that support other living organisms. While pollinators play a large role in cropping systems, little is known about their presence and function in rangeland ecosystems, which have recently become fragmented and overexploited at an extraordinary rate. We assessed local Maasai knowledge on insect pollinators and how pollinators affect livelihood diversification in Simanjiro rangelands, Tanzania. Through questionnaires, key informant interviews, focus group discussions, and field observations, we found varied insect knowledge among Maasai herders. Lasioglossum of sub genus Ipomalictus and Syriphidae were the least commonly recognized pollinators as only 24%, and 7% of participants could identify them, respectively. Responses varied significantly between men and women (F = 7.397, p = .007). Commiphora africana, Acacia mellifera and Albizia anthelmintica were noted as most important bee forage plants while observations showed Aspilia mossambicensis, Justicia debile and Acacia tortilis. Most (77%) of Maasai herders showed limited ability to link pollinators and rangeland wellbeing. Beekeeping contributed to livelihood diversification for 61% of respondents, with women participating more frequently than men (χ2 = 46.962, p = .0001). Beekeeping was positively influenced by education level ( R = .421, p < .0001) and occupation ( R = .194, p = .009). Pollinator declines were attributed to climate change (47%), agriculture (37%), and habitat destruction (8%). We conclude that Maasai have limited knowledge of common pollinator groups and their roles. Community outreach and training should bridge the knowledge gap in pastoralist communities to fully realize pollinator benefits and highlight the importance of rangeland health.

Is ground cover a useful indicator of grazing land condition?

Remotely sensed ground cover data play an important role in Australian rangelands research development and extension, reflecting broader global trends in the use of remotely sensed data. We tested the relationship between remotely sensed ground cover data and field-based assessments of grazing land condition in the largest quantitative analysis of its type to date. We collated land condition data from 2282 sites evaluated between 2004 and 2018 in the Burdekin and Fitzroy regions of Queensland. Condition was defined using the Grazing Land Management land condition framework that ranks grazing land condition on a four point ordinal scale based on dimensions of vegetation composition, ground cover level and erosion severity. Nine separate ground cover derived indices were then calculated for each site. We found that all indices significantly correlated with grazing land condition on corresponding sites. Highest correlations occurred with indices that benchmarked ground cover at the site against regional ground cover assessed over several years. These findings provide some validation for the general use of ground cover data as an indicator of rangeland health/productivity. We also constructed univariate land condition models with a subset of these indices. Our models predicted land condition significantly better than random assignment though only moderately well; no model correctly predicted land condition class on &gt;40% of sites. While the best models predicted condition correctly at &gt;60% of A and D condition sites, condition at sites in B and C condition sites was poorly predicted. Several factors limit how well ground cover levels predict land condition. The main challenge is modelling a multidimensional value (grazing land condition) with a unidimensional ground cover measurement. We suggest that better land condition models require a range of predictors to address this multidimensionality but cover indices can make a substantial contribution in this context.

Soil properties in northern temperate pastures do not vary with management practices and are independent of rangeland health

Studies examining the influence of disturbance and management history on pasture soils across a large sampling area are uncommon. We report on the soil properties found in 102 northern temperate pastures sampled in central Alberta, Canada, and relate these attributes to ongoing pasture management practices compiled from producer surveys and aboveground measures of rangeland health (RH). Tame pastures, typically seeded to introduced forages, were associated with higher soil fertility (total carbon, nitrogen, and organic matter) than semi-native grasslands, which were associated with coarse-textured soils. Soil properties remained independent of most grazing and pasture management practices, including the grazing systems, class of livestock, fertilization, and stocking rate. However, manure application, often combined with harrowing, was associated with improved soil fertility and increased electrical conductivity (salinity). Soils with a fire history reported by land managers, largely in the Boreal natural region, were characterized by a greater soil C:N ratio. Soil surface properties (litter cover, litter depth, and bare soil) were responsive to grazing management, with growing season and year-round grazing associated with a thinner litter layer having less cover, and bare ground twice as high under continuous grazing compared with pastures rotationally grazed. Further, variation in soil surface cover was associated with contrasting RH classes (healthy, healthy with problems, and unhealthy), whereas soil attributes remained unrelated to RH. This study demonstrates that soils within these northern temperate grasslands are relatively insensitive to many pasture management practices, and highlights that existing RH assessments may provide limited insight into differences in mineral soil properties.