Volume 17 Nos. 1 & 2


Histopathological changes in microbially infected forest tree seeds

 

Hyspathological study of microbially infected forest tree seeds was conducted to determine the effect of different fungi on the cellular structures of artificially and naturally infected seeds

The mode of infection of Colletotrichum gloeosporioides, Fusarium moniliforme, andPhoma sp. on artificially inoculated seeds ofPterocarpus indicus Willd (narra), Lasiodiplodia theobromae (Ldt), F. moniliforme, and F. solani onSwietenia macrophylla King (mahogany); and F. solani on Samanea saman (Jacq.) Merr. (raintree) was described. Ramification of the hyphal structures from the seed coat to the subepidermal layer and some parts of the cotyledon of narra and endosperm of mahogany was observed. Hyphal growth of F. solani was concentrated mainly on seed coat and less penetration was observed beyond the epidermal layer of raintree seeds.

Cellular structures of naturally infected seeds of Anisoptera thurifera Blume (dagang),Parashorea malaanonan (Blanco) Merr. (bagtikan), Gliricidia sepium (Jacq.) Steud. (kakawate), and Intsia bijuga (Coleobr) O. Ktze (ipil), particularly embryos, were greatly damaged by various fungi. Intercellular and intracellular penetration of hyphal structures caused destruction on the cellular membrane in and outside the embryo leading to non-germinability of seeds.

A high temperature of 29-30oC and relative humidity of 85% and above favored infection and disease development of both artificially and naturally infected seeds.

 

 

Survey and identification of typhoon resistant reforestation species

 

Four frequently utilized reforestation species in the Bicol Region were evaluated as to typhoon resistance under field conditions in Bacacay, Albay. Agoho (Casuarina equisetifolia), mahogany (Swietenia macrophylla), river red gum (Acacia auriculiformis), and yemane (Gmelina arborea) were evaluated in terms of five different damage categories, namely: (1) defoliation, (2) breaking of branches and twigs, (3) breaking of main trunk or stem, (4) leaning, and (5) toppling down or uprooting. Sampling plots were laid out in Completely Randomized Design in four replications under a ten-year-old plantation at spacing of 2 m x 2 m to 4 m x 4 m with 25 trees per treatment or damage category. All species used were located on top of mountain ridges where impact of typhoon was expected to be greatest. Percentages of affected trees were counted after the occurence of typhoon. Data analysis was made using F test, and means were compared using Duncan Multiple Range Test (DMRT).

Results indicated highly significant differences among treatments or damage categories. Agoho (Casuarina equisetifolia) was found to be one of the most resistant in all damage categories assessed, and could be recommended in reforesting exposed, high elevation, and typhoon-prone areas. Its resistance was attributed to its needle-like foliage, spherical canopy structure, high wood tensile strength, and a deep root system.

An index of species resistance to typhoon in terms of the different damage categories as well as the recovery rate of the different species was determined.

 

 

Broadleaf diversity and carbon estimates along the northeastern slope of Mt. Makiling, Philippines

 

Three elevation ranges of the Mt. Makiling were identified: low elevation (50-300 m asl), middle elevation (301-700 m asl), and high elevation (701-1114 m asl). The purpose of the study was to determine the diversity of broad-leaved species and the corresponding carbon stocks along the elevation gradient. Within these ranges, vegetation samplings for broadleaf were done on tree, intermediate, and undergrowth layers using the Quadrat Sampling Technique. A total of 110 species, 75 genera, and 35 families identified. Family Moraceae and genus Ficus had the highest number of occurrence in all elevation ranges, while Swietenia macrophylla was the most abundant species that had occurred from low to middle elevations while partially open in high elevation. The ecological values also showed that density, frequency, and dominance were higher on these elevations, where Parashorea malaanonan and Pterocymbium tinctorium had the highest Importance Value (IV) recorded. The diversity values in all ranges were generally low to moderate. The highest diversity was observed in high elevation that exhibited a trend of increasing from low to middle elevation, then decreasing from middle to high elevation. Similarly, aboveground biomass and carbon density exhibited the same trend by which they were highest at the middle elevation where plantations of S. macrophylla and dipterocarps are located. The largest estimate for carbon density was 451.62 + 50.07 Mg C/ha at 400 m asl and the lowest was 94.58 + 24.12 Mg C/ha at 900 m asl. Overall, these ecological parameter studies were found to have a significant implication to ecological management, social factors, and research.

 

 

Elements of sustainability in forest governance: An analysis of the community-based projects in Diffun, Quirino and VIBANARA, Ilagan, Isabela

 

The study aimed to identify what constitutes and what are the elements of sustainability in forest governance. It employed the case study method in analyzing the implementation of the CBFM projects in Don Mariano Perez, Diffun, Quirino and VIBANARA, Ilagan, Isabela.

There are two contending worldviews and concepts on forests that permeate and shape the implementation of forestry programs - the forest as an economic resource and as a social system. Although the concept of a social system is gradually gaining ground, the persistency of the utilitarian view among DENR personnel, LGUs, and forest communities explains why projects give more emphasis on timber harvesting activities than forest protection and development.

Forest policy making in the Philippines remains to be highly centralized and top-down. DENR central authorities usually craft policies with the limited involvement of the field personnel and other stakeholders. The highly centralized structure of program management of CBFM hinders the participation of other stakeholders.

The CBFM program has four major stakeholders: 1) DENR - the lead implementing agency, 2) LGUs- province, municipality, and barangay, 3) NGOs, and 4) forest communities. The conflicting concerns and interests of these stakeholders on the forest largely affect the mode and extent of collaboration in forest governance.

The inadequacy in the implementation of forestry programs could be attributed to the absence or limited availability of supportive strategies and mechanisms in the projects. These include, among others, funds and logistics, human resources capabilities, technological support, marketing schemes, incentive system, and sanctions and penalty schemes.

The study concludes that the three elements of sustainable forest governance, which are forest policies, stakeholders' complementation and collaboration, and supportive strategies and mechanisms, are necessary ingredients to ensure the sustainability of forestry programs and projects. All these elements should work and genuinely be operationalized beyond policy provisions.

 


Perception and attitude towards ecosystem services in the urban areas

 

Rapid and continuous urbanization is inevitable in the very near future. This phenomenon is the cause of many problems that could adversely affect the quality of life (QOL) of urban area inhabitants. Urban green spaces could address these problems by providing various benefits, which are known as ecosystem services (ES). The study sites were the Kanto Region which represents an urban area in a developed country and Metro Manila. Action Grid Analysis shows that the priority ES in the urban areas are: air pollution control, greenhouse gas reduction, heat island mitigation, and water pollution control. The quantity and quality of the sources of these four ES (i.e., urban green spaces) should be improved to increase the environmental benefits from ES.