Various issues related to oil palm production, such as biodiversity, drought, water scarcity, and water and soil resource exploitation, have become major challenges for environmental sustainability. The water footprint method indicates that the quantity of water used by plants to produce one biomass product could become a parameter to assess the environmental sustainability for a plantation. The objective of this study is to calculate the water footprint of oil palm on a temporal scale based on root water uptake with a specific climate condition under different crop age and soil type conditions, as a means to assess environmental sustainability. The research was conducted in Pundu village, Central Kalimantan, Indonesia. The methodology adopted in carrying out this study consisted of monitoring soil moisture, rainfall, and the water table, and estimating reference evapotranspiration (ETo), root water uptake, and the oil palm water footprint. Based on the study, it was shown that the oil palm water usage in the observation area varies with different crop ages and soil types from 3.07–3.73 mm/day, with the highest contribution of oil palm water usage was in the first root zone which correlates to the root density distribution. The total water footprint values obtained were between 0.56 and 1.14 m3/kg for various plant ages and soil types. This study also found that the source of green water from rainfall on the upper oil palm root zone delivers the highest contribution to oil palm root water uptake than the blue water from groundwater on the bottom layer root zone.

Kendala pengembangan budidaya pertanian di Desa Umbulrejo Kecamatan Ponjong Kabupaten Gunung Kidul Provinsi Daerah Istimewa Yogyakarta adalah ketersediaan air. Potensi sumberdaya air di Kecamatan Ponjong selain air hujan adalah air tanah dangkal yang berasal dari sistem sungai bawah tanah, telaga karst serta mata air. Kecamatan ponjong merupakan kawasan kars sehingga lahan di kawasan tersebut merupakan lahan kering dengan masalah utama pengembangan budidaya pertanian adalah ketersediaan air terutama di musim kemarau. Salah satu upaya meningkatkan produksi budidaya pertanian adalah melalui pemanfaatan air tanah dangkal sebagai sumber air pertanian. Pemanfaatan air tanah dangkal memerlukan pompa air untuk menaikkan air ke permukaan. Penggunaan pompa bertenaga solar selain menimbulkan permasalahan lingkungan juga memerlukan biaya operasional yang tinggi, demikian pula dengan penggunaan pompa listrik. Selaian permasalahan biaya operasional, ketersedian system jaringan sampai kelahan pertanian juga menjadi factor penghambat. Salah satu alternative yang dapat mengatasi permasalahan lingkungan dan biaya operasional serta sistem jaringan di atas, adalah pompa air tenaga surya/matahari. Kabupaten Gunung Kidul merupakan kawasan yang memiliki potensi energy listrik dari radiasi matahari berkisar 4,9 s.d. 5,1 kWh/m2. Kata Kunci : Air tanah dangkal, irigasi, pompa air, panel surya

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Various environmental challenges, related to oil palm commodity has became a major environmental challenge to oil palm production. The aim and objective of this study is to analyze the actual water footprint of oil palm based on root water uptake under varying crop age and soil type. The research was conducted in Pundu Village, Central Kalimantan. The methodology adopted in carrying out this study consists of various stages which includes observing soil moisture, rainfall, and water table, ETo, root water uptake and oil palm water footprint. The highest rate of water consumption was the 13 years oil palm on spodosol soil type with an average daily rate of 3.73 mm/day. The lowest evapotranspiration was represented by the 7th year oil palm on spodosol with an average rate of 3.07 mm/day. The total water footprint value obtained was between 0.56 – 1.14 m3/kg for a variety of plants with various age and soil types. It can be deduced that the water footprint value of oil palm vary for different crop age and soil types on temporal scale. The study also presented that the source of green water from the first root zone of oil palm deliver the highest contribution for oil palm root water uptake.

The Palingkau Swamp Irrigation Scheme SP1 SP2 SP3 extends tidal irrigation between Kapuas Murung River and Kapuas River, which local peoples developed. The development of the new agricultural land behind the old tidal irrigation system creates oxidation of potential acid sulphate (FeS2) soil. The result of the leaching process polluted local’s agricultural area causes the decrease land productivity. The field observation recorded the water pH ranges between 3.9 - 5.3; 3.7 - 4.31 at the handil; 2.5 - 4 at the collector channels; and 2.8 - 3.6 at the primary channels. Good water management is needed to overcome these problems, both at the new irrigation system and handil. The HECRAS mathematical model is used to evaluate water circulation in the system and its reliability. The Efforts to normalize the handil impact increasing the amount of water entering the handil although it is not significant. Moreover, it still cannot meet the water demand for the leaching process in the network system by 2.06 million m3/day. It is necessary to increase the capacity of the channel to allow freshwater flow from the river for the leaching process in the network system.