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Relawan Kuswandi

Bio: Relawan Kuswandi is an academic researcher. The author has contributed to research in topics: Latitude & Logging. The author has an hindex of 3, co-authored 5 publications receiving 26 citations.

Papers
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Journal ArticleDOI
TL;DR: Based on the current inventory of permanent sampling plots (PSPs) in Indonesia, there is high potential to establish a long-term collaborative forest monitoring network as discussed by the authors, which can help us understand and better conserve these exceptionally diverse ecosystems.
Abstract: Permanent sampling plots (PSPs) are a powerful and reliable methodology to help our understanding of the diversity and dynamics of tropical forests. Based on the current inventory of PSPs in Indonesia, there is high potential to establish a long-term collaborative forest monitoring network. Whilst there are challenges to initiating such a network, there are also innumerable benefits to help us understand and better conserve these exceptionally diverse ecosystems.

21 citations

Journal ArticleDOI
TL;DR: In this article , a high-resolution map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots is presented.
Abstract: The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers. Examining drivers of the latitudinal biodiversity gradient in a global database of local tree species richness, the authors show that co-limitation by multiple environmental and anthropogenic factors causes steeper increases in richness with latitude in tropical versus temperate and boreal zones.

13 citations

Journal ArticleDOI
TL;DR: In this paper, the authors investigated stand structures in a logged-over area of tropical forest in South Papua, where four species were selected in three one-hectare permanent sample plots: Vatica rassak, Syzygium sp, Litsea timoriana and Canarium asperum.
Abstract: Selective logging has been taking place in Papua for several decades. In contrast, very little is known about the stand structure in post-logged forest. Hence, this paper investigates stand structures in logged-over area of tropical forest in South Papua. Four species were selected in three one-hectare permanent sample plots (PSPs): Vatica rassak, Syzygium sp, Litsea timoriana and Canarium asperum. PSPs were located in the forest concession area of PT. Tunas Sawaerma in Assiki, Boven Digul, in South Papua. Data sets comprised measurements made in 2005 and 2012 consisting of species, diameter at breast height (DBH), mortality and number of tree of each species. Integral Projection Models (IPMs) were developed, taking into account mortality, growth, recruitment and fecundity. Results show the pattern of stand structures of the four species were more or less similar, i.e. more individual trees were present in the small diameter classes than in the larger diameter classes. The general pattern of the individual distribution of the four species is the typical reverse-J shape. Syzygium sp. has a greater number of individuals in the small diameter classes than the other three species. Population growth rates (λ) are above one, indicating that the stand structures of the population dynamics of the four species are recuperating. Conclusively, these results suggest that species composition and population structure in these logged-over forests are recovering increasingly.

7 citations

Journal ArticleDOI
TL;DR: The results showed that the understory and upper story vegetation had different patterns of heterospecific association, which enrich the knowledge in theoretical ecology of tropical forests, especially in New Guinea.
Abstract: . Murdjoko A, Jitmau MM, Djitmau DA, Siburian RHS, Ungirwalu A, Wanma AO, Mardiyadi Z, Rumatora A, Mofu WY, Sineri AS, Fatem SM, Worabai D, May NL, Tokede MJ, Warmetan H, Wanggai CB, Wanma JF, Sirami EV, Paembonan JB, Unenor E, Kuswandi R, Lekitoo K, Khayati L, Benu NMH, Tambing J, Saragih ASB. 2020. Heterospecific and conspecific associations of trees in lowland tropical forest of New Guinea. Biodiversitas 21: 4405-4418. The vegetation in the tropical rainforest of New Guinea consists of a large number of species that interact with each other within and among species. While several studies have attempted to reveal the diversity of flora of New Guinea, little is known about plant communities that develop associations. This study aimed to investigate the associations of tree species in lowland tropical forest in New Guinea. The associations depicted in this study were in the form of conspecific associations (among small and large individuals within same species) and heterospecific (among individuals of different species and divided into under and upper story). We established 48 rectangular plots created in Murkim and Teiraplu as part of Pegunungan Bintang Regency, Papua Province. Canonical correspondence analysis (CCA) was used to analyze heterospecific and conspecific associations. The results showed that the understory and upper story vegetation had different patterns of heterospecific association. The understory configured three heterospecific associations, consisting of 5, 13, and 90 species, while the upper story formed four heterospecific associations with 4, 8, 11, and 63 species. The analysis of conspecific associations showed of 149 tree species recorded in the study sites, only 66 species that had both small and large individuals, displaying the pattern of conspecific association. Among them, 41 species had positive associations while 25 species had negative associations. Our findings enrich the knowledge in theoretical ecology of tropical forests, especially in New Guinea.

6 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used Permanent Sample Plots (PSPs) for monitoring the growth and yield of the managed stand and found that there was a difference in stand structure (tree number) of each diameter class both in plots with treatment and without treatment.
Abstract: Forest stand structure could be used as one of the variables in deciding the possibility to harvest forest product. On logged-over forests, data and information over stand structure could become the basis for decision making for harvesting. To measure and analyze yield on logged-over forest, each forest management unit (IUPHHK) is obligated to establish Permanent Sample Plots (PSPs) for monitoring the growth and yield of the managed stand. In some of the plots, maintenances and thinning treatments are applied while other plots are not treated. The results, after several years of observations, showed that there was a difference in stand structure (tree number) of each diameter class both in plots with treatment and without treatment. The rate of in-growth, up-growth and mortality varied between plots without and with treatment in each diameter class and length of time after harvesting. The average diameter increment of trees in the stands of the untreated plots was higher (0.60 cm yr -1 ) compared to the treated plots (0.55 cm yr -1 ).

6 citations


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01 Jan 2014
TL;DR: In this article, the authors developed a conceptual framework that explains the process of data sharing from the primary researcher's point of view, which can be divided into six descriptive categories: data donor, research organization, research community, norms, data infrastructure, and data recipients.
Abstract: Despite widespread support from policy makers, funding agencies, and scientific journals, academic researchers rarely make their research data available to others. At the same time, data sharing in research is attributed a vast potential for scientific progress. It allows the reproducibility of study results and the reuse of old data for new research questions. Based on a systematic review of 98 scholarly papers and an empirical survey among 603 secondary data users, we develop a conceptual framework that explains the process of data sharing from the primary researcher’s point of view. We show that this process can be divided into six descriptive categories: Data donor, research organization, research community, norms, data infrastructure, and data recipients. Drawing from our findings, we discuss theoretical implications regarding knowledge creation and dissemination as well as research policy measures to foster academic collaboration. We conclude that research data cannot be regarded a knowledge commons, but research policies that better incentivize data sharing are needed to improve the quality of research results and foster scientific progress.

198 citations

Journal ArticleDOI
Cecilia Blundo1, Julieta Carilla1, Ricardo Grau1, Agustina Malizia1  +549 moreInstitutions (176)
TL;DR: In this paper, the authors show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots.

66 citations

Journal Article
TL;DR: The tropical managed forests Observatory (TmFO) as discussed by the authors is a network of permanent sample plots in logged tropical forests, which provides unprecedented opportunities to examine long-term data on the resilience of logged and disturbed tropical forests at regional and global scales.
Abstract: While attention to logging in the tropics has been increasing, studies on the long-term effects of silviculture on forest dynamics and ecology remain scare and spatially limited Indeed, most of our knowledge on tropical forests arise from studies carried out in undisturbed tropical forests This bias is problematic given that logged and disturbed tropical forests are covering now a larger area than the so-called primary forests The Tropical managed Forests Observatory (TmFO), a new network of permanent sample plots in logged forests, aims to fill this gap by providing unprecedented opportunities to examine long-term data on the resilience of logged tropical forests at regional and global scales TmFO currently includes 24 experimental sites distributed across three tropical regions, with a total of 536 pem1anent plots and about 1200 ha of forest inventories In this paper we will present the main results generated by the network on the impact of logging on Carbon and timber recovery, as well as biodiversity changes in the Amazon basin and South East Asia

47 citations

Journal ArticleDOI
TL;DR: Damayanto et al. as discussed by the authors provided updated taxonomical information of bamboo species in Lombok and investigated the accuracy of previous studies regarding the existence of several non-native Indonesian bamboo species on the island (i.e. they do not have original distribution in Indonesia).
Abstract: . Damayanto IPGP, Rustiami H, Miftahudin, Chikmawati T. 2020. A Synopsis of Bambusoideae (Poaceae) in Lombok, Indonesia. Biodiversitas 21: 4489-4500. There is little documentation of bamboo on Lombok. Non-native Indonesian bamboos have been reported occurring in Lombok. As such, suspicious bamboo specimens and information in those reports need to be examined and possibly re-determined. This study aimed to provide updated taxonomical information of bamboo species in Lombok and to investigate the accuracy of previous studies regarding the existence of several non-native Indonesian bamboo species on the island (i.e. they do not have original distribution in Indonesia). Data from fieldwork were combined with specimens in Herbarium Bogoriense to create a synopsis of bamboo in Lombok and to develop an identification key to the species. Eleven species of bamboos in Lombok were reported from this study, namely Bambusa glaucophylla, B. maculata, B. multiplex, B. spinosa, B. vulgaris, Dendrocalamus asper, Gigantochloa apus, G. atter, Schizostachyum brachycladum, S. lima, and Thyrsostachys siamensis. Several doubtful species (B. albustiata, B. ventricosa, Guadua angustifolia, S. jaculans, Pseudosasa japonica) were presented to clarify the existence of a non-native Indonesian bamboo in Lombok. Moreover, there is not enough evidence to state Dinochloa sp. occurred in Lombok. The results of this study can be used by stakeholders for bamboo identification and as the baseline taxonomic account for future studies and conservation of bamboo species in Lombok.

9 citations