Coffee plantation management has an important role in soil quality in order to increase coffee production. Biopore Infiltration Hole with Compost (BIHC) can increase soil available water capacity. In this study, the goal was to improve soil available water capacity in a coffee plantation with the implementation of the BIHC. This study was conducted at PTPN XII Bangelan, Malang, on March - August 2020. A randomized block design with seven treatments and four replications was used. The BIHC consisted of two-hole depths (30 cm and 60 cm) and two types of compost (goat manure and coffee pulp compost). The soil characteristics observed were water retention (pF) and C-organic at soil depths of 0-20, 20-40, and 40-60 cm. The coffee tree observed were number of leaves and chlorophyll content. Data obtained were subjected to analysis of variance (ANOVA) by the F test and Duncan's Multiple Distance Rate Test (DMRT) at 5% probability, using SPSS program. Results of the study showed that BIHC was able to increase the content of soil C-organic and the available water capacity significantly compared with control treatment. The BIHC implementation could increase soil available water capacity up to 65% at a soil depth of 0-20 cm, up to 60% at a soil depth of 20-40 cm, and up to 51% at a soil depth of 40-60 cm more than the control treatment. The soil available water capacity suggested a significant positive correlation (p≤0.05) with the leaves number of coffee tree and chlorophyll content of leaves.

Sloping topography, clay textures and improper fertilizer application create a high risk of surface runoff and nutrient loss. Phosphorus occurs as an important nutrient in coffee beans. The objective of this research is to analyze the effects of biopore infiltration hole with compost (BIHC) on the total and available phosphorus in robusta coffee in Bangelan plantation, Malang. A complete randomized block design with 4 replications was applied and the treatments consisted of control and BIHC. The BIHC process involved biopore hole depth of 30 and 60 cm for the goat manure and coffee pulp compost, respectively. Several parameters were also observed, including pH, total and available phosphorus as well as soil organic carbon (SOC) between 0-20, 20-40 and 40-60 cm in soil depth. Subsequently, the analysis of variance (ANOVA) and Duncan's Multiple Range Test (DMRT) were used to comprehend the data. The results showed the ability of BIHC to significantly increase the pH, SOC and total-P, compared to the control with less available-P. These total-P improvements up to 103.27, 108.73 and 132.09% were reported at soil depths between 0-20, 20-40 and 40-60 cm, respectively, while available-P were possibly enhanced up to 77.59, 28.27 and 151.99% at corresponding depth ranges.

Agriculture land shows soil compaction problems due to long-term agricultural cultivation activities. Soil compaction indicator can be seen from the value of soil penetration resistance at different soil depths (0 - 60 cm). This research aimed to determine soil penetration resistance at different coffee plantation ages with different soil depths and to analyze the relationship between soil penetration resistance with soil physical characteristics and coffee productivity. The survey activities include observation of minipits, measuring soil penetration resistance at soil depths of 0-20 cm, 20-40 cm, and 40-60 cm using a hand penetrometer, and soil sampling. The results showed that the soil penetration resistance at each LU and soil depth suggested variation were categorized into moderate and high soil penetration resistance classes (1.34 MPa - 3.35 MPa). Soil characteristics, such as soil aggregate stability, water content, bulk density, porosity, silt content, and clay content, significantly correlate with soil penetration resistance. However, soil penetration resistance has a negative correlation with coffee productivity. The value of soil penetration resistance (at a depth of 0-60 cm) has a significant negative correlation with the average productivity of coffee plantations (r=-0.5936**). Therefore, increased soil penetration resistance decreased root growth, decreasing plant productivity.