Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Effects of weaning age and weight on lamb growth rate of Morada Nova breed raised in a tropical extensive production system Efeito da idade e do peso ao desmame no ganho de peso de cordeiros Morada Nova criados em sistema extensivo de produção no trópico

The aim of this research were to study the effect of weaning age and weight on post-growing rate (PWG) and to estimate the optimal weaning age (WA) and weight (WW) of Morada Nova-white variety breed lambs raised under extensive system conditions. A total of 31 male and female lambs were evaluated, being 19 lambs born in April/May 2001 and 12 lambs born in February/March 2002. Lambs were distributed in the following treatments at weaning: 1) weaning age = T1: weaned at 60 days; T2: weaned at 75 days; T3: weaned at 90 days, and 2) weaning weight = T1: weaned with 9 to 10.4kg weigth; T2: weaned with 10.5 to 12.4kg weight and T3: weaned with above 12.5kg weight. The PWG was recorded through successive weightings done every fourteen days from weaning to 180 days of age. Data were analysed through a statistical model that included age and weight at weaning, sex and year of birth as fixed effects. Lambs weaned with 60, 75 and 90 days of age showed non-significant differences (P>0.05) on PWG. However, WW had a significant influence (PO trabalho teve como objetivo avaliar o efeito da idade e do peso ao desmame no ganho de peso posterior de cordeiros da raça Morda Nova-variedade branca, bem como determinar a idade e o peso mais adequados de desmame de cordeiros mantidos em sistema extensivo de criação. Foram avaliados 31 cordeiros machos e fêmeas, sendo 19 nascidos nos meses de abril e maio e 12 nascidos durante os meses de fevereiro e março de 2002. Ao desmame, os cordeiros foram distribuídos nos seguintes tratamentos, considerando-se: 1) idade ao desmame (ID) = T1: desmame com 60 dias de idade; T2: desmame com 75 dias de idade; T3: desmame com 90 dias de idade; e 2) peso ao desmame (PD) = T1: desmame com peso entre 9 - 10,4kg; T2: desmame com peso entre 10,5 - 12,4; T3: desmame com peso acima ou igual a 12,5kg. O crescimento posterior dos cordeiros foi avaliado através de pesagens sucessivas quinzenais até atingirem a idade de 180 dias. Os dados foram analisados pelo procedimento estatístico GLM, considerando-se a idade e o peso ao desmame, o sexo e o ano de nascimento como variáveis independentes. Cordeiros desmamados com 60, 75 e 90 dias de idade não apresentaram diferenças significativas (P<0,05) nos ganhos de peso pós-desmame, porém observaram-se diferenças entre os grupos de peso ao desmame. Cordeiros desmamados com peso entre 9 e 10,4kg apresentaram pesos pós-desmame inferiores (P<0,05) aos desmamados com pesos entre 10,5 e 12,4kg e acima ou igual a 12,5kg, não havendo diferenças entre esses últimos grupos. O sexo teve efeito significativo (P<0,05) no peso dos cordeiros, sendo os machos mais pesados que as fêmeas (20,7kg e 17,6kg, respectivamente). O ano de nascimento não teve efeito significativo no ganho de peso pós-desmame dos cordeiros. Conclui-se que o peso ao desmame é mais importante que a idade no ganho de peso pós-desmame e que o peso mínimo para o desmame de cordeiros da raça Morada Nova, em condições extensivas de criação, é de 10,5kg