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"Keberadaan kawasan tepi pada suatu habitat hutan dapat menimbulkan efek tepi yang memengaruhi respons berbagai organisme berupa pergeseran habitat atau pola persebaran, salah satunya ialah herba terestrial. Berbagai penelitian terdahulu mengenai efek tepi terhadap herba terestrial memberikan hasil yang berbeda-beda. Penelitian yang bertujuan untuk mengetahui pengaruh efek tepi terhadap komunitas herba terestrial di hutan kota Universitas Indonesia telah dilakukan. Pengukuran parameter efek tepi dilakukan dengan mengetahui komposisi spesies pada tiap plot penelitian, perhitungan Indeks Nilai Kepentingan (INK), indeks keanekaragaman dan kemerataan Shannon-Wiener, dan pengukuran parameter lingkungan. Komposisi spesies menunjukkan kecenderungan respons positif terhadap efek tepi. Berdasarkan perhitungan INK diketahui spesies dominan Axonopus compressus pada kawasan tepi, Centotheca lappacea pada kawasan tengah, dan Amorphophallus variabilis pada kawasan inti. Hasil uji t pada indeks keanekaragaman Shannon-Wiener menunjukkan terdapat perbedaan yang signifikan pada pasangan plot tepi-inti dan tengah-inti, sementara itu tidak terdapat perbedaan yang signifikan pada pasangan plot tepi-tengah. Tidak terdapat pola respons tertentu terhadap efek tepi berdasarkan indeks Shannon-Wiener. Hasil uji Kruskal-Wallis menunjukkan terdapat perbedaan yang signifikan pada pengukuran parameter suhu udara, kelembapan udara dan intensitas cahaya. Tidak terdapat perbedaan pada pengukuran parameter pH tanah. Uji korelasi menunjukkan terdapat korelasi positif antara parameter suhu udara dan intensitas cahaya matahari terhadap penambahan jumlah spesies. Sementara itu tidak ada korelasi antara kelembapan udara dan pH tanah terhadap jumlah spesies. Terdapat dua belas spesies yang memiliki potensi sebagai spesialis kawasan tepi, namun tidak ditemukan spesies yang memiliki potensi sebagai spesialis kawasan inti.

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The existence of edges in a forest habitat can cause edge effects that affect the response of various organisms in the form of habitat or distribution pattern shifts, one of which is terrestrial herbs. Previous studies on the effects of edges on terrestrial herbs have had different results. The study aimed to determine the effect of edge effects on terrestrial herb communities in urban forests of Universitas Indonesia was conducted. Measurement of the edge effect parameters was done by investigating the composition of species in each research plot, calculating the Importance Value Index (IVI), Shannon-Wiener`s index of diversity and evenness, and measuring environmental parameters. The species composition showed a tendency towards a positive response to edge effects. Based on the calculation of IVI it was known that the dominant species at each area namely Axonopus compressus at the edge, Centotheca lappacea at the middle, and Amorphophallus variabilis at the core. The results of t test on the Shannon-Wieners diversity index show that there were significant differences between edge-core and middle-core pair plots, while there were no significant differences between edge-middle pair plot. There were no specific response patterns for edge effects based on the Shannon-Wieners index. The Kruskal-Wallis test results showed that there were significant differences in the measured air temperature, humidity, and intensity of sunlight parameters. There werent any differences in the measured soil pH parameter. Correlation test shows there were positive correlations between the parameters of air temperature and the intensity of sunlight on the addition of species number. Meanwhile there were no correlation between air humidity and soil pH on the addition of species number. There were twelve potential species categorized as edge area specialists, while there werent any species that have potential as core area specialists."

"Plant communities have been attracting many scientists due to their complexity and unclear underlying mechanisms that support it. How large numbers of competing plant species manage to coexist, for instance, is one of the major unresolved questions in plant community ecology. Ecological niche concept is a classical theory which tries to address this question. The development of this concept will be presented in this paper. Recent studies, although few in number and incomplete in many ways, do suggest that plants segregate along various environmental niche axes. Although it is unlikely that niche separation along environmental axes is the only mechanism of coexistence in any large community, the evidence now suggests that ecological niche concept plays a more significant role than has been previously appreciated."

"Invasion Dynamics depicts how non-native species spread and perform in their novel ranges and how recipient socio-ecological systems are reshaped and how they respond to the new incursions. It collects evidence for grouping patterns of spread into four types and three associated phenomena, discusses candidate explanations for each pattern, and introduces analytic tools for capturing and forecasting invasion dynamics. Special attention is given to the potential mechanisms of boosted range expansion and nonequilibrium demographic dynamics during invasion. The diverse mechanisms that drive direct and mediated biotic interactions between invaders and resident species are elucidated, and triggers of potential regime shifts in recipient ecosystems are identified. It further explores the ways in which local and regional species assemblages are reshuffled and reorganized. Efficient management of invasions requires not only insights on invasion dynamics across scales but also objective assessment of ecological and economic impacts, as well as sound protocols for prioritizing and optimizing management effort. Biological invasions, therefore, involve more than the actions of invaders and reactions of invaded ecosystems; they represent a co-evolving complex adaptive system with emergent features of network complexity and invasibility. Invasions are thus a formidable force that acts in concert with other facets of global change to initiate the adaptive wheel of panarchy and shape the altered biosphere in the Anthropocene."

"Penelitian struktur komunitas ikan dilakukan di Sungai Citirem, mulai dari bulan Januari--Juni 2010. Pengambilan data dilakukan dengan menggunakan jaring insang (gill net), serokan, dan alat setrum listrik (electrofishing). Penentuan stasiun penelitian dengan menggunakan metode purposive sampling. Tujuan penelitian adalah untuk mengetahui komposisi, kelimpahan, keanekaragaman jenis, hubungan antar jenis dalam komunitas, dan keunikan jenis ikan di Sungai Citirem. Hasil penelitian tercatat 22 jenis ikan dari 12 suku. Gobiidae merupakan suku yang paling dominan dengan 10 jenis ikan. Puntius binotatus merupakan jenis ikan yang paling melimpah. Berdasaran indeks keanekaragaman jenis Shannon-Wiener (H’), dapat disimpulkan bahwa keanekaragaman jenis ikan tertinggi terdapat di daerah hilir sungai (1,822) dan keanekaragaman jenis ikan terendah terdapat di daerah tengah sungai (0,343). Selain itu, hasil penelitian menunjukkan adanya keunikan jenis ikan di Sungai Citirem. Hal tersebut dapat dilihat dari terdapatnya jenis ikan yang merupakan jenis tunggal dalam sukunya."

"Interest in the temporal fluctuations of biological populations can be traced to the dawn of civilization. How can mathematics be used to gain an understanding of population dynamics? This monograph introduces the theory of structured population dynamics and its applications, focusing on the asymptotic dynamics of deterministic models. This theory bridges the gap between the characteristics of individual organisms in a population and the dynamics of the total population as a whole. In this monograph, many applications that illustrate both the theory and a wide variety of biological issues are given, along with an interdisciplinary case study that illustrates the connection of models with the data and the experimental documentation of model predictions. The author also discusses the use of discrete and continuous models and presents a general modeling theory for structured population dynamics. Cushing begins with an obvious point: individuals in biological populations differ with regard to their physical and behavioral characteristics and therefore in the way they interact with their environment. Studying this point effectively requires the use of structured models. Specific examples cited throughout support the valuable use of structured models. Included among these are important applications chosen to illustrate both the mathematical theories and biological problems that have received attention in recent literature."