Abstract:The aim of this research was to know the impact of planting leguminous cover crops (LCCs) of Mucuna bracteata and Calopogonium mucunoides in oil palm plantation on peatland on reducing CO 2 emissions. Atmosphere temperature, peat surface temperature, in-closed chamber temperature and peat surface CO 2 fluxes were monitored on two adjacent experimental plots. The first experimental plot was on the newly opened peat surface (NOPS) and another was on the eight years planted oil palm land (EPOL). The closed chamber techniques adopted from International Atomic Energy Agency (IAEA) (1993) were implemented to trap CO 2 emissions emitted from 24 treatment plots at the 1st, 3rd and 6th months observations. Average CO 2 fluxes observed on no LCCs plots in the NOPS site were 61.25 ± 8.98, 33.76 ± 2.92 and 33.75 ± 3.45 g/m 2 h , while in the EPOL site were 55.38 ± 15.95, 29.90 ± 5.32 and 27.70 ± 4.62 g/m 2 h at the 1st, 3rd and 6th months monitoring, respectively. Average CO 2 fluxes observed on the planted M. bracteata plots in the NOPS site were 68.2 ± 24.5, 12.88 ± 3.70 and 10.40 ± 1.28 g/m 2 h, whereas in the EPOL site were 54.04 ± 6.70, 11.45 ± 2.00 and 9.33 ± 3.49 g/m 2 h at the 1st, 3rd and 6th months monitoring, respectively. Average CO 2 flux observed on the planted C. mucunoides plots in the NOPS site were 66.5 ± 23.7, 15.41 ± 1.51 and 9.74 ± 2.55 g/m 2 h, while in the EPOL site were 47.00 ± 5.00, 9.34 ± 1.23 and 10.52 ± 4.80 g/m 2 h at the 1st, 3rd and 6th months, respectively. P-value for the experimental sites was 0.008 (< 0.05), indicating the significant difference in the level of CO 2 fluxes between the sites. P-value for the treatments in the experimental plots was 0.000 (< 0.05), indicating markedly different level of CO 2 fluxes among treatments. P-value for the age of M. bracteata and C. mucunoides planted on the experimental plots was 0.000 (< 0.05), indicating the significant difference in the level of CO 2 fluxes due to the enhanced LCCs age performing at the increase of shading effects. The comparison of CO 2 fluxes among experimental plots shows that planting M. bracteata and C. mucunoides on the peatland could reduce CO 2 emission.

<p>Soil is an important factor in peanut cultivation as a nutrient provider. In recent years, peanut production has dwindled due to the decrease in soil fertility. Boron as a micronutrient can maximize peanut production through optimum viability of flowers and phosphor as essential nutrients for peanut to improve its pod filling. This study aims to examine the application of boron and phosphor growth and formation of peanut gynophore. The research was conducted from September 2017 to January 2018 in Sambirembe village, Magetan. The experiment uses randomized complete block design (RCBD) with the first factor applied on the dose of boron fertilizer (0, 1, 2 3 kg ha^-1) and the second was on the dose of phosphor fertilizer (0, 75, 100, 150 kg ha^-1), repeated 3 times. Boron application resulted in the highest plant height at the fourth week by 10.45%. The application of 1 kg ha^-1 boron without phosphorus (0 kg ha^-1) yielded the highest gynophore formation, i.e. 42.</p>

This study is aimed to evaluate soil degradation based on Standard Criteria of Soil Degradation for Biomass Production under Indonesian Government Regulation No. 150 in 2000. Conducted at Jatipurno District, Keduang Sub-Watersheds, between October and December 2016, at seven selected land units, each land unit is represented by four sample points. The selection of sampling area is according to Stratified Purposive Sampling method. The evaluation of soil degradation is carried out by determining the threshold value and key factors of soil characteristics based on the Standard Criteria of Soil (matching process), which lead to degradation. The results showed that the entire soil at Jatipurno District is slightly degraded. The most extensive soil degradation 2,869.31 ha area (69.60%) is caused by a low colloid fraction, high bulk density, low total porosity and low soil permeability. The soil degradation mostly caused by low soil permeability which the number is under critical threshold &lt; 0.7 cm hour^-1 in the entire land units. Implementing providing organic matter to the soil, planting variations of cover crops, on land plots (low, medium, high cover crops), land management by crop rotation and intercropping, minimum tillage in accordance with the rules of environmental conservation, can be done to minimize the soil degradation.

Indonesia is a country with the third largest biodiversity after Brazil and Madagascar. Of the about 325.530 species of flora and fauna globally, an estimated 25% of the world's species are found in Indonesia. Macrofauna, a land animal that plays a role in influencing the soil ecosystem has specific environmental requirements that enables it to be used as biological indicators of ecosystem conditions, mainly rice paddy ecosystem. This research is necessary owing to the demand for an easy and accurate indicator in predicting soil fertility for farmers. In addition, this study conducted in July TO August 2018 can be used as an inventory of macrofauna indigenous species that may still remain in the paddy field, Dukuhseti district. The implementation of observations was done in paddy fields in the Dukuhseti district in Pati regency, Central Java. Macro fauna specimens and soil samples were taken at various points. 121 individual macro faunas were found and divided into three phyla and 10 Order. The results showed that macro fauna diversity was not always positively correlated with soil chemical properties. Total N, available P, organic C and pH is not directly proportional to the increasingly diverse types of macro fauna in a rice field. The soil's chemical nature in the form of base saturation has a positive correlation with macro fauna diversity that makes it serve as an indicator of fertility. Base saturation in the fields can be associated with the presence of different kinds of macrofauna decomposers such as earthworms, millipedes and denitrivor. Indigenous macrofauna species was not found in the paddy fields in the Dukuhseti district due to intensive land management.

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