Kemudahterancaman (vulnerability) penduduk terhadap perubahan guna tanah di Selangor

The changes in land use and land cover indicate the development changes that occur at a certain place. Selangor has an area of 796,084 hectares and consists of nine districts. The state government of Selangor plans to achieve the most developed state status by the year 2005. Consequently, land use patterns have changed tremendously, especially within the past five years. The change in land use, especially from forest to non-forest, results in environmental degradation that will eventually threaten human life in that particular area. Whether we realize it or not, the change in land use may increase people’s vulnerability in a society that tries to achieve development in line with the framework of sustainable development. This article will examine the changes in land use and land cover which has occurred within the last four decades (1966-2001) using Geographical Information Systems (GIS) and its relationship with vulnerability to human life in the surrounding area. In this context, the driving forces to the changes will be looked at in a holistic and integrated manner. Among the driving forces of change that will be discussed are state development policies, foreign direct investment, population change, urbanization and infrastructure developmen

Keperluan peta kerentanan bencana sebagai input dalam pengurusan guna tanah: kajian kes Universiti Kebangsaan Malaysia

Limpahan pesat aktiviti tepu bina di UKM Bangi untuk memenuhi kehendak dan juga keperluan warganya menjadikan ia setara fungsi satu pekan kecil. Di samping pembangunan yang pesat, UKM turut mengalami insiden kegagalan cerun, tanah runtuh dan banjir kecil di beberapa kawasan dalam kampus. Kajian ini direka untuk menyepadukan maklumat pelbagai dimensi untuk menyokong membuat keputusan dalam pengurusan guna tanah untuk menangani isu bencana di kampus ini. Objektif kajian adalah untuk: mengenal pasti maklumat pelbagai dimensi yang menyumbang kepada bencana di UKM dan membangunkan satu peta kerentanan tanah runtuh dan banjir untuk menyokong dalam membuat keputusan secara termaklum. Melalui pendekatan heuristik, tiga kaedah utama telah digunakan untuk menghasilkan peta kerentanan tanah runtuh dan banjir iaitu: analisis kandungan untuk mengenal pasti kriteria yang menyumbang kepada tanah runtuh dan banjir; elisitasi pakar untuk memberi nilai pemberat terhadap kriteria; dan analisis tindan-lapis untuk memproses dan menjana peta tematik. Kriteria yang menyumbang kepada tanah runtuh dan banjir dikategorikan kepada faktor hujan, topografi, struktur geologi dan ciri-ciri geomorfologi yang seterusnya diberi nilai pemberat. Peta kerentanan tanah runtuh yang terhasil menunjukkan kelas kerentanan tinggi merupakan kelas terbesar di UKM dengan keluasan sebanyak 6.10 km2 bersamaan 51.91% daripada jumlah keluasan asal kampus. Analisis terhadap lokasi insiden lepas mendapati kesemua taburan tanah runtuh berlaku pada kelas kerentanan sederhana, tinggi dan sangat tinggi. Hampir separuh daripada jumlah taburan tanah runtuh berlaku pada kelas kerentanan tinggi iaitu 57.14% yang merupakan peratusan terbesar. Peta kerentanan banjir menunjukkan UKM turut terdedah kepada banjir. Majoriti kawasan kampus didominasi oleh kelas kerentanan sederhana dengan keluasan sebanyak 6.5 km2 kira-kira hampir 56% daripada keluasan asal. Aset penting universiti dan laluan utama kampus ini yang bersebelahan dengan saliran sungai terletak di dalam kawasan berkerentanan tinggi. Situasi ini agak membimbangkan kerana terdapat infrastruktur penting di sekitar kawasan ini. Input berguna yang diperoleh melalui kajian ini telah menunjukkan keupayaan peta kerentanan tanah runtuh dan banjir sebagai medium yang bermaklumat dalam perancangan guna tanah sebelum menjalankan sebarang aktiviti pembangunan di sesuatu kawasan

The Emerging Widespread Debris Flow Disasters in Tropical Terrain of Peninsular Malaysia: Understanding the Risk and Policy Intervention

Several widespread debris flow disasters stroke Peninsular Malaysia in between 2021 and 2022, scattered across the country. It was the first time for this hazard being nationally recognised as a type of geological disaster in the country. Debris flow disaster is not a new phenomenon. It had been recorded since 1995, however, in the past they were isolated incidents and did not attract much attention. The recent widespread debris flow disasters started in Gunung Jerai, Kedah on 18 August 2021; followed by similar incidents but in 3 different states concurrently in (1) Bentong, Pahang, (2) Hulu Langat, Selangor, and (3) Jelebu, Negeri Sembilan on 18 December 2021; Kenyir, Terengganu on 27 February 2022; and finally at Gunung Inas, Kedah on 4 July 2022. These disasters sparked numerous technical and social issues where heated debates on whether they were purely due to natural processes or caused anthropogenic activities. Previously, debris flow phenomena in Malaysia were so rare, that the term ‘debris flow’ was not familiar to the lay public. The term of “debris flow” was often disregard or used interchangeable with ‘water surge’ phenomena by the media and public, especially for sudden sediment water surge from hilly upstream after intense rainfall at hillside river catchment areas, normally occurs during the monsoon season. The ordinary water surge has significantly lesser level of destruction and momentum as compared to a debris flow with higher debris-type sediments. This paper discusses the emerging issues of debris flow in Malaysia and some initiatives being carried out in in facing the geohazard. The Department of Mineral and Geoscience Malaysia and a team of local geohazard experts have taken the lead to carry out studies to understand the sudden emergence of widespread and cascading debris flow events in Malaysia. As a result, proposal on policy intervention was put forward to the relevant government ministries; post-disaster programme has been continuously carried out to educate the communities on the geological disaster risks through community-based disaster risk management (CBDRM)

Kesan Gempa 7.6 Mw Padang Indonesia, 30 September 2009(Earthquake impacts of the Mw 7.6, Padang, Indonesia, 30 September 2009)

Gempa bumi pada 30 September 2009, dengan kekuatan 7.6 MW yang melanda Bandar Padang, Padang Pariaman dan wilayah Sumatera Barat, Indonesia, telah mengorbankan lebih daripada 1200 orang. Ribuan buah rumah, bangunan dan infrastruktur lain telah mengalami kerosakan tahap ringan hingga teruk. Kajian ini bertujuan untuk melaporkan kesan gempa bumi Padang terhadap kerosakan bangunan dan tanah runtuh yang berlaku pada kawasan Bandar Padang, Padang Pariaman, Pariaman dan Agam. Kesan gempa bumi ini dianalisis berdasarkan data geologi, geoteknik dan impak geo-bencana yang telah dikumpulkan daripada berbagai sumber dan hasil kajian lapangan. Hasil kajian menunjukkan bahawa kerosakan di kawasan bandar Padang dan Padang Pariaman lebih disebabkan oleh kualiti bangunan yang tidak memenuhi piawaian bangunan dan pengaruh geologi kawasan, iaitu berlakunya amplifikasi tanah disebabkan oleh endapan aluvium yang tebal. Kerosakan teruk pada bangunan antara lainnya dikaitkan dengan kehadiran jalur-jalur sesar kecil atau ketakselanjaran pada lapisan bawah tanah. Beberapa kejadian tanah runtuh besar yang berlaku di Pariaman dan Agam adalah disebabkan oleh geologi kawasan, geomorfologi dan morfologi cerun yang curam. Kajian lanjut diperlukan bagi mengenal pasti dan menilai risiko bencana untuk persediaan menghadapi bencana gempa bumi di masa hadapan

The Emerging Widespread Debris Flow Disasters in Tropical Terrain of Peninsular Malaysia: Understanding the Risk and Policy Intervention

Several widespread debris flow disasters stroke Peninsular Malaysia in between 2021 and 2022, scattered across the country. It was the first time for this hazard being nationally recognised as a type of geological disaster in the country. Debris flow disaster is not a new phenomenon. It had been recorded since 1995, however, in the past they were isolated incidents and did not attract much attention. The recent widespread debris flow disasters started in Gunung Jerai, Kedah on 18 August 2021; followed by similar incidents but in 3 different states concurrently in (1) Bentong, Pahang, (2) Hulu Langat, Selangor, and (3) Jelebu, Negeri Sembilan on 18 December 2021; Kenyir, Terengganu on 27 February 2022; and finally at Gunung Inas, Kedah on 4 July 2022. These disasters sparked numerous technical and social issues where heated debates on whether they were purely due to natural processes or caused anthropogenic activities. Previously, debris flow phenomena in Malaysia were so rare, that the term ‘debris flow’ was not familiar to the lay public. The term of “debris flow” was often disregard or used interchangeable with ‘water surge’ phenomena by the media and public, especially for sudden sediment water surge from hilly upstream after intense rainfall at hillside river catchment areas, normally occurs during the monsoon season. The ordinary water surge has significantly lesser level of destruction and momentum as compared to a debris flow with higher debris-type sediments. This paper discusses the emerging issues of debris flow in Malaysia and some initiatives being carried out in in facing the geohazard. The Department of Mineral and Geoscience Malaysia and a team of local geohazard experts have taken the lead to carry out studies to understand the sudden emergence of widespread and cascading debris flow events in Malaysia. As a result, proposal on policy intervention was put forward to the relevant government ministries; post-disaster programme has been continuously carried out to educate the communities on the geological disaster risks through community-based disaster risk management (CBDRM)