Predicting the effects of grazing management on moorland bird abundance

2005 ◽  
Vol 2005 ◽  
pp. 69-69
Author(s):  
S. M. Gardner ◽  
G. M. Buchanan ◽  
J. W. Pearce-Higgins ◽  
M. C. Grant

Field studies of grazing management have frequently concluded that the magnitude and direction of vegetation response is dependent on initial vegetation condition. On upland heath, this dependence reflects the importance of small-scale ecological processes (e.g. plant competition), and local neighbourhood effects (e.g. spatial distribution of plant species), in driving the vegetation dynamics. These small-scale effects, together with variation in grazing patterns, increase the difficulty of deriving general rules about the effect of grazing on vegetation change from field studies. However, we need to determine the impacts of such grazing-related vegetation change upon biodiversity, (e.g. birds). For many bird species it is impractical to use experimental approaches due to low breeding densities, and the influence of other site and management effects (e.g. predator control). To predict the effect of management changes on them requires an accurate assessment of the large-scale effects of grazing management on the ecological landscape using data from small-scale field studies. This paper sets out an approach that integrates field studies with theoretical models to investigate the large-scale effects of grazing management on plant and bird communities on upland heath.

2016 ◽  
Vol 4 (1) ◽  
pp. 34
Author(s):  
Muna Aprilianto ◽  
Tomoliyus Tomoliyus

Penelitian ini bertujuan untuk menghasilkan buku pedoman bermain sepakbola untuk meningkatkan aspek psikologis (semangat, gembira, dan disiplin) anak usia 12-13 tahun di Yogyakarta. Penelitian ini merupakan penelitian dan pengembangan yang terdiri atas dua tahapan yaitu tahap penelitian pendahuluan terdiri dari kajian literatur, kajian penelitian relevan, studi lapangan dan tahap pengembangan terdiri perencanaan, validasi ahli, uji skala kecil, dan uji skala besar. Peneliti ini mengambil sampel dari sekolah sepakbola di Yogyakarta. Teknik sampling yang digunakan adalah purposive sampling. Pada uji coba skala kecil dilakukan di SSB Real Madrid melibatkan 10 siswa dan satu orang pelatih. Pada uji coba skala besar dilakukan di dua tempat yaitu di SSB Real Madrid dan SSB Bina Putra Jaya Sleman melibatkan 38 siswa dan dua pelatih. Analsis data dalam penelitian ini menggunakan teknik analisis deskriptif kuantitatif dan kualitatif. Hasil validasi menunjukkan model bermain sepakbola anak usia 12-13 tahun layak untuk diuji cobakan. Berdasarkan Hasil pelaksanaan pada uji coba skala kecil dan besar secara substansi isi dan pelaksanaan tergolong sangat baik. Hasil penilaian efektivitas model tehadap psikologis anak berupa semangat, gembira, dan disiplin mengalami peningkatan: nilai pertemuan kedua lebih tinggi dari pertemuan pertama. Dapat disimpulkan model bermain sepakbola anak usia 12-13 tahun efektif untuk meningkatkan aspek psikologis berupa semangat, gembira, dan disiplin siswa dalam melakukan latihan sepakbola.Kata Kunci: model, bermain, psikologis, sekolah sepakbola Development a playing soccer model to improve the psychological aspects of 12-13 years old children in Yogyakarta AbstractThis research aims to develop a playing soccer model to improve the psychological aspects (spirit, joy, and discipline) of 12-13 years old children in Yogyakarta. This study is a research and development which consists of two stages. The Preliminary research stage and development stage. The Preliminary research stage consisted of a literature review, relevant research studies and field studies. The Development stage consisted of planning, validation expert, small-scale test, and test large scale. The Validation involve three people experts. The sampel of take it from soccer school in Yogyakarta. The small-scale tryout was conducted on 10 students and one coach of Real Madrid Soccer School in Yogyakarta. The large-scale trials were conducted with two soccer school on 38 students and two coach of Yogyakarta Real Madrid Soccer School and Sleman Bina Putra Jaya Soccer School. The resul is a playing soccer model for children aged 12-13 years with the title "Playing Soccer in Practice to Improve Psychological Aspects". Based on the small-scale tryout and the small-scale tryout content implementation aspects are in an excellent category. The Psychological development of students assessment resulting in the form of passion, joy, and discipline in playing soccer show improvement: score of the second meeting is greater than the average score of the first meeting, thus it can be concluded thaat the playing soccer model for children age 12-13 years is effective to improve students’ psychological aspects, including the aspects of spirit, joy, and discipline in doing soccer practice.Keywords: models, play, psychological, soccer school


2017 ◽  
Vol 5 (2) ◽  
pp. 183 ◽  
Author(s):  
Puput Widodo ◽  
Ria Lumintuarso

Penelitian ini mengadaptasi penelitian dan pengembangan pendidikan model Borg & Gall dengan menyederhanakan menjadi 2 tahapan sebagai berikut (1) tahap pra-pengembangan, tahapan ini meliputi (a) kajian literatur dan penelitian relevan dan (b) studi lapangan, (2) tahap pengembangan, tahapan ini meliputi (a) penyusunan draf, (b) validasi ahli, (c) uji coba model skala kecil, (d) uji coba model skala besar, dan (e) produk akhir. Uji coba skala kecil dilakukan terhadap 30 anak kelas atas SDN Aditirto Pejagoan Kebumen, Provinsi Jawa Tengah. Uji coba skala besar dilakukan terhadap 130 anak kelas atas dari SD Negeri 1 Karangpoh, 26 siswa SD Negeri 1 Logede, 22 siswa SD Negeri 4 Pejagoan, 24 siswa SD Negeri 1 Kebulusan, dan 30 siswa SD Negeri 3 Kebulusan Kecamatan Pejagoan, Kabupaten Kebumen, Provinsi Jawa Tengah. Instrumen yang digunakan untuk mengumpulkan data adalah wawancara, kuisioner penilaian karakter permainan tradisional, kuisioner observasi pengembangan permainan tradisional, kuisioner observasi keefektifan model permainan tradisional, kuisioner penilian observasi ahli media, dan kuisioner evaluasi siswa. Hasil penelitian berupa pengembangan model permainan tradisional terdiri dari 3 jenis permainan yaitu: (1) permainan goteng, (2) lari papan/segi empat, dan (3) kasti tangan. Berdasarkan penilaian para ahli materi dan guru penjasorkes dapat disimpulkan bahwa pengembangan model permainan tradisional yang disusun sangat baik dan efektif, sehingga model permainan layak digunakan untuk pembelajaran pendidikan jasmani pada siswa kelas atas. Developing Models of Traditional Games to Build Characters of Elementary School Students of Upper Grades AbstractThe study was conducted through two stages by adapting the research and development of educational models Borg & Gall as follows (1) pre-development stage, this stage include (a) review of relevant literature and research, and (b) field studies, (2) the development stage, this stage include; (a) drafting, (b) validation expert, (c) testing of small-scale models, (d) testing large-scale models, and (e) of the final product.The small-scale tryout was conducted by involving 30 students of upper grades of state elementary schools (SES) of Aditirto, Pejagoan sub-district, Kebumen regency, Central Java porovinsi. The large-scale tryout was conducted by involving 130 students of upper grades of SES 1 of Karangpoh, 26 students of SES 1 of Logede, 22 students of SES 4 of Pejagoan, 24 students of SES 1 of Kebulusan, and 30 students of SES 3 of Kebulusan Pejagoan sub-district, Kebumen regency, Central Java porovinsi. The data collecting instruments were an interview guideline, a questionnaire to assess characters of traditional games, a questionnaire to assess the traditional game development, a questionnaire for the assessment by the media expert, and a questionnaire for the evaluation by students. The results of the study of the development of models of traditional games were three types of games, i.e: (1) goteng game, (2) board/rectangle running, and (3) hand kasti. Based on the assessment by the materials experts and the teachers of physical, sports, and health education, it could be concluded that the developed modals of traditional games were very good and effective so that they were appropriate to be used in the learning physical education for the students of upper grades.


2021 ◽  
Author(s):  
Xingyu Zhang ◽  
◽  
Matteo Ciantia ◽  
Jonathan Knappett ◽  
Anthony Leung ◽  
...  

When testing an 1:N geotechnical structure in the centrifuge, it is desirable to choose a large scale factor (N) that can fit the small-scale model in a model container and avoid unwanted boundary effects, however, this in turn may cause scale effects when the structure is overscaled. This is more significant when it comes to small-scale modelling of sinker root-soil interaction, where root-particle size ratio is much lower. In this study the Distinct Element Method (DEM) is used to investigate this problem. The sinker root of a model root system under axial loading was analysed, with both upward and downward behaviour compared with the Finite Element Method (FEM), where the soil is modelled as a continuum in which case particle-size effects are not taken into consideration. Based on the scaling law, with the same prototype scale and particle size distribution, different scale factors/g-levels were applied to quantify effects of the ratio of root diameter (𝑑𝑟) to mean particle size (𝐷50) on the root rootsoil interaction.


1992 ◽  
Vol 6 ◽  
pp. 11-11
Author(s):  
Richard B. Aronson

In many cases, it is not possible to explain evolutionary-scale patterns by analogy to ecological processes. However, in at least some cases, biological interactions appear amenable to such extrapolation. The paleobiological literature contains examples of predation, competition, and herbivory in which the dynamics are similar on multiple spatiotemporal scales.Dense populations of epifaunal, suspension-feeding ophiuroids, or brittlestar beds, are widely distributed, but they are rare and are restricted in their habitat distribution. On a small scale (meters to kilometers, hours to days), brittlestar bed distribution in the British Isles and the Bahamas is limited by predatory fishes and crabs. On an intermediate scale (tens to hundreds of kilometers, decades to centuries), predation by seastars may cause cycles of ophiuroid abundance in the western English Channel, beyond the stringent restrictions imposed by fish and crab predators. On a large scale (globally, millions to tens of millions of years), the Jurassic decline of brittlestar beds is associated with the diversification of predatory teleosts, neoselachian sharks, and decapod crustaceans.Small-scale predator-ophiuroid interactions sum to produce analogous intermediate- and large-scale interactions. Predation effects on brittlestar beds appear to be scale-independent, or fractal. Fractal scaling may be a consequence of self-organized criticality, an inherent property of large, interactive systems.


2018 ◽  
Vol 22 (2) ◽  
pp. 213-225 ◽  
Author(s):  
Richard N. Belcher ◽  
Keren R. Sadanandan ◽  
Emmanuel R. Goh ◽  
Jie Yi Chan ◽  
Sacha Menz ◽  
...  

2012 ◽  
Vol 3 (1) ◽  
pp. 453-483
Author(s):  
F. Cresto Aleina ◽  
V. Brovkin ◽  
S. Muster ◽  
J. Boike ◽  
L. Kutzbach ◽  
...  

Abstract. Sub-grid processes occur in various ecosystems and landscapes but, because of their small scale, they are not represented or poorly parameterized in climate models. These local heterogeneities are often important or even fundamental for energy and carbon balances. This is especially true for northern peatlands and in particular for the polygonal tundra where methane emissions are strongly influenced by spatial soil heterogeneities. We present a stochastic model for the surface topography of polygonal tundra using Poisson-Voronoi Diagrams and we compare the results with available recent field studies. We analyze seasonal dynamics of water table variations and the landscape response under different scenarios of precipitation income. We upscale methane fluxes by using a simple idealized model for methane emission. Hydraulic interconnectivities and large-scale drainage may also be investigated through percolation properties and thresholds in the Voronoi graph. The model captures the main statistical characteristics of the landscape topography, such as polygon area and surface properties as well as the water balance. This approach enables us to statistically relate large-scale properties of the system taking into account the main small-scale processes within the single polygons.


2019 ◽  
Vol 30 (3) ◽  
pp. 381-395 ◽  
Author(s):  
MICHAEL DVORAK ◽  
BIRGIT FESSL ◽  
ERWIN NEMETH ◽  
DAVID ANCHUNDIA ◽  
JAVIER COTÍN ◽  
...  

SummaryWe documented the consequences of large-scale habitat loss on a community of Galápagos native bird species on San Cristóbal island, based on point counts conducted between 2010 and 2017. Surprisingly, despite considerable habitat change and a variety of other threats, the landbirds of San Cristóbal have fared much better than on the neighbouring islands Floreana or Santa Cruz. While two species went extinct very soon after human colonisation, the majority have adapted well to subsequent vegetation change and habitat loss. The endemic San Cristóbal Mockingbird Mimus melanotis is more widespread than previously thought and its population seems to be stable since the 1980s. We thus propose a change in IUCN classification from ‘Endangered’ to ‘Near threatened’. We present evidence gained by interviewing locals which suggests that a small population of the Least Vermilion Flycatcher Pyrocephalus dubius, classified as ‘Extinct’ by BirdLife International, may have persisted until very recently. Although extensive searches in 2018 and 2019 were unsuccessful, the possibility remains that a few birds may have survived in remote parts of the island. Further searches that involve the general public and other interested parties are therefore deemed necessary.


1988 ◽  
Vol 1 (21) ◽  
pp. 157
Author(s):  
J.W. Van der Meer ◽  
K.W. Pilarczyk

A number of large scale tests on stability of rock slopes and gravel beaches is described and compared with small scale test results. The following topics are treated: the stability of a rock armour layer, the profile formation of a berm breakwater, the profile formation of gravel beaches, including ripple formation, and reflection and overtopping on rock slopes. The general conclusion is that scale effects could not be found.


2020 ◽  
Vol 13 (12) ◽  
pp. 6407-6426
Author(s):  
Maurits L. Kooreman ◽  
Piet Stammes ◽  
Victor Trees ◽  
Maarten Sneep ◽  
L. Gijsbert Tilstra ◽  
...  

Abstract. The ultraviolet (UV) Absorbing Aerosol Index (AAI) is widely used as an indicator for the presence of absorbing aerosols in the atmosphere. Here we consider the TROPOMI AAI based on the 340 nm/380 nm wavelength pair. We investigate the effects of clouds on the AAI observed at small and large scales. The large-scale effects are studied using an aggregate of TROPOMI measurements over an area mostly devoid of absorbing aerosols (Pacific Ocean). The study reveals that several structural features can be distinguished in the AAI, such as the cloud bow, viewing zenith angle dependence, sunglint, and a previously unexplained increase in AAI values at extreme viewing and solar geometries. We explain these features in terms of the bidirectional reflectance distribution function (BRDF) of the scene in combination with the different ratios of diffuse and direct illumination of the surface at 340 and 380 nm. To reduce the dependency on the BRDF and homogenize the AAI distribution across the orbit, we present three different AAI retrieval models: the traditional Lambertian scene model (LSM), a Lambertian cloud model (LCM), and a scattering cloud model (SCM). We perform a model study to assess the propagation of errors in auxiliary databases used in the cloud models. The three models are then applied to the same low-aerosol region. Results show that using the LCM and SCM gives on average a higher AAI than the LSM. Additionally, a more homogeneous distribution is retrieved across the orbit. At the small scale, related to the high spatial resolution of TROPOMI, strong local increases and decreases in AAI are observed in the presence of clouds. The BRDF effect presented here is a first step – more research is needed to explain the small-scale cloud effects on the AAI.


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