When Will Plant Morphology Affect the Shape of a Seed Dispersal “Kernel”?

2001 ◽  
Vol 211 (3) ◽  
pp. 229-238 ◽  
Author(s):  
R.D. COUSENS ◽  
A.A. RAWLINSON
Biotropica ◽  
2017 ◽  
Vol 49 (3) ◽  
pp. 395-401 ◽  
Author(s):  
Katherine Bunney ◽  
William J. Bond ◽  
Michelle Henley

2021 ◽  
Author(s):  
Eli Bussel

The gypsy moth (Lymantria dispar) is among the most destructive invasive species in North America, responsible for defoliating millions of hectares of oak forest. The spatial dynamics of defoliating lepidopteran populations, such as those of the gypsy moth, are thus of great interest to forestry and conservation efforts. Despite numerous studies on the long-range dispersal patterns of defoliators, there is comparatively little theoretical understanding or field research concerning short-range dispersal via ballooning. Previous studies of ballooning have assumed random diffusion, but these models cannot account for non-random biases, such as the effect of wind on the angle of dispersal.Here, I develop models of short-range dispersal in larvae via ballooning, informed by methods from the seed dispersal kernel literature. I then fit models to field data of gypsy moth larvae dispersal using MCMC to perform Bayesian inference, and PSIS-LOO to perform model selection. I found that dispersal kernel models are able to reliably detect biases in angle of dispersal due to wind direction, and allow for testing of correlations between experimental variables and measures of dispersal. These modeling methods can help inform future studies into short-range larval dispersal and provide a novel framework with which to analyze dispersal data.


2016 ◽  
Vol 1 (1) ◽  
pp. 1
Author(s):  
Suraida Suraida

Abstrak Penelitian ini dilakukan karena proses pembelajaran di laboratorium Biologi IAIN STS Jambi yang masih minim sarana prasarana yang ada di laboratorium, sehingga menghambat proses pembelajaran khususnya untuk mata kuliah Morfologi Tumbuhan. Penelitian ini bertujuan mengembangkan buku ajar praktikum dan mengetahui praktikalitasnya. Jenis Penelitian ini adalah penelitian pengembangan (Research and Development) dengan menggunakan 4-D Models yang terdiri dari 4 tahap yaitu Define, Design, Develop dan Disseminate. Karena adanya keterbatasan waktu dan biaya maka tahap disseminate tidak dilakukan. Produk yang dikembangkan berupa buku ajar praktikum yang divalidasi oleh validator. Produk yang telah divalidasi dan dinyatakan valid oleh validator, kemudian diujicobakan pada proses pembelajaran yang bertujuan untuk melihat nilai praktis buku ajar praktikum di laboratorium Biologi. Analisis data yang digunakan adalah data deskriptif untuk memvalidasi perangkat pembelajaran oleh pakar pendidikan. Selain itu juga diteliti data praktikalitas penggunaan perangkat pembelajaran ini yang diperoleh dari observasi dosen dan respon siswa. Nilai validitas produk 83,31% yang dikategorikan valid. Sementara nilai kepraktisan berdasarkan data observasi keterlaksanaan SAP, angket respon dosen dan siswa dikategorikan sangat baik atau sangat praktis. Penelitian menyimpulkan bahwa perangkat pembelajaran di Laboratorium Biologi yang dikembangkan adalah valid dan sangat praktis digunakan baik dosen maupun siswa. Kata Kunci : Pengembangan, buku ajar praktikum, laboratorium biologi Abstract [The development of a course book for plant morphology at biology laboratory] This research was triggered by the limited facilities of the biology laboratory at the State Institute of Islamic Studies Sulthan Thaha Saifuddin Jambi which became a constrain in the teaching and learning process of Plant Morphology classroom sessions. The objective of this research was to develop a course book as well as to reveal its practicality. The researcher did a research and development using 4-D Models consisting of four stages namely; define, design, develop, and disseminate. Considering the limitation of time and finance, the disseminate stage was not executed. The test revealed the validity score of the product was 83,31% which categorized as good. For its practicality, the product was considered as very good based on observation of lesson plan execution and lecturers’ and students’ response. In summary, the course book developed for the course at Biology Laboratory was categorized as valid and practical to be used by both students and lecturers. Keywords: development, a course book, biology laboratory


2008 ◽  
Vol 1 (1) ◽  
pp. 7-18
Author(s):  
Luciane Lopes de Souza

Biotic or abiotic processes of seed dispersal are important for the maintenance of the diversity, and for the natural regeneration in tropical forests. Ichthyochory is one of the fundamental mechanisms for seed dispersal in flooded environments, as the “igapó” forests. A study on the ichthyochory of the igapós was conducted at Amanã Sustainable Development Reserve, in the middle Solimões river, from June 2002 to September 2004. Monthly samples of frugivorous fish were taken, with the main fishing gears used locally. Guts of 1,688 fish caught were examined. The main species were Myloplus rubripinnis (29.21%), Hemiodus immaculatus (18.96%),Colossoma macropom um (16.23%) and Mylossoma duriventre (16.05%). The diet was made of vegetables (fruits, leave and flowers), and animals (arthropods). 53.02% of all fish caught ingested fruits. The total number of intact seeds in the stomachs and intestines were 8,069 and 5,763 respectively. About 61.9% of the Brycon melanopterus (matrinchão), 46.34% of the Brycon amazonicus (mamuri) and 30.22% of M . rubripinnis (parum ) analysed had intact seeds in their guts. Seeds of Nectandra amazonum and Genipa spruceana ingested proved to be more viable than those non-ingested by fish. The high rates of frugivory, the presence of intact seeds in the guts of fish and the greater viability of ingested seeds all suggest that these animals are important seed dispersors in the “igapó” forests of Amanã Reserve.


2005 ◽  
Vol 166 (3) ◽  
pp. 368 ◽  
Author(s):  
Katul ◽  
Porporato ◽  
Nathan ◽  
Siqueira ◽  
Soons ◽  
...  

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