Diversity of plants and mammals as indicators of the effects of land management types in woodlands

Background:The ecological indicators are useful tools to determine the effects of human disturbances on woodland biodiversity.Nevertheless,ecological indicators not always responded in the same way to disturbances,and the responses can differ among taxa.In arid and semiarid woodlands,the use of deadwood associated with cattle raising can affect biodiversity and Nature’s contributions to people.Methods:Our study aimed to assess changes in taxonomic and functional diversity of two assemblages,plants and mammals,in Prosopis woodlands under different land management types:grazed woodlands and a protected area.For plants,changes in structural diversity were also analyzed.Prosopis trees under different land management types were selected and their deadwood characteristics were registered.Through live traps and camera traps,we obtained data on the presence-absence of mammals per tree to estimate diversity indices.For plants,we measured the abundance of vegetation by species and by cover type through the Line-Intercept Method to estimated diversity.Finally,we built generalized linear models to assess the responses of diversity of each assemblage to covariables concerning deadwood and different land management types.Results:We found that all diversity indeces for plants were either negatively affected by the presence of deadwood on the ground,or favored by its extraction.For mammals,removal of deadwood increased taxonomic diversity,while functional diversity increased with deadwood on the trees.Both structural diversity of plants and functional diversity of mammals were greater in grazed woodlands.Conclusions:The sustainable use of woodland resources is essential for the activities of rural communities.Our study results indicated that land management of grazed woodlands promoted the structural diversity of plant assemblages and the functional diversity of mammals.The presence of deadwood negatively affected plant diversity but it increased mammal functional diversity.It is advisable to maintain trees that preserve their wooden structure within the managed areas to promote the functional diversity of mammals,while trees with extraction from standing wood will favor the functional diversity of the plant assemblage.Understanding the effects of human disturbances can contribute to management for the conservation of woodlands diversity and Nature’s contributions to people.

Fishing for Success

Innovative solutions unleash the full potential of Zimbabwe＇saquacultureZIMBABWEAN farmer Abel Gurupira used to think that aquaculture had nothing to do with cattle breeding.As a fact,at Milan Wood,his 15-hectare farm in Mashonaland West Province,fish,cattle and poultry used to be raised separately.But things changed after the visit of Pan Tingshuang,a Chinese aquaculture expert,in the region.

Assessing the Environmental Impact of Extensive Beef Production in Grazing Lands of Argentina

Because of environmental constraints,beef cattle was for more than a century the only viable farming option in the extensive semiarid and subhumid lands of Argentina and the main source of nutrients for humans as well.However,a growing concern and criticism have risen today about its possible negative impact on the climate and the environment.These worries tend to affect current public opinions,national policies,and international trade.Based on 40 beef cattle farms scattered across different semiarid and subhumid regions of Argentina,here we evaluated the impact of extensive cattle production on carbon,water,and nutrient pollution.Life-Cycle Assessment(LCA)and Land-Based Assessment(LBA)were the two approaches we used here to compare the environmental impact of beef production.While the environmental footprint(EF)resulting from LCA expresses the impact per unit of food,the environmental balance(EB),derived from LBA,aims at quantifying the impact per unit of land.As such,the EB considers both negative and positive impacts on the farm as an integrated system.Following standardized procedures,we evaluated EF and EB up to the farm gate,leaving aside delocalized post-farm impacts such as those of processing,packaging,and transportation that occur beyond the farm gate.In agreement with previous evidence,our results show that the EF tends to decrease as per-head production increases.Correlation coefficients and statistical significance were the following for carbon(R=−0.574;p<0.01),water(R=−0.561;p<0.01),and N(R=−0.704;p<0.01)and Phosphorus(P)pollution(R=−0.802;p<0.01)footprints.On the contrary,the EB seems to be highly sensitive,and as per-hectare beef production increases.Correlations were the following for carbon emissions(CE:R=0.955;p<0.01),water consumption(WC:R=0.822;p<0.01),nitrogen excretion(NE:R=0.948;p<0.01)and phosphorus excretion(PE:R=0.945;p<0.01).What our results suggest is that the notion of EF is useful to evaluate the environmental impact in intensive beef production systems,and the EB is suitable to assess the impact of the extensive ones.In practice,both approaches provide different perspectives on the environmental-impact problem and they should be complementary used.We concluded that the methodological rigidity of EF does not allow proper discrimination among farms in the extensive systems.On the contrary,the EB approach tended to be highly sensitive to detecting differences between individual farms and farmers,thus allowing the identification of successful options for extensive beef production in terms of public image,policy-making,and commercial opportunities.